drivers/i2c/busses/i2c-stm32f7.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Driver for STMicroelectronics STM32F7 I2C controller
   4  *
   5  * This I2C controller is described in the STM32F75xxx and STM32F74xxx Soc
   6  * reference manual.
   7  * Please see below a link to the documentation:
   8  * http://www.st.com/resource/en/reference_manual/dm00124865.pdf
   9  *
  10  * Copyright (C) M'boumba Cedric Madianga 2017
  11  * Copyright (C) STMicroelectronics 2017
  12  * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
  13  *
  14  * This driver is based on i2c-stm32f4.c
  15  *
  16  */
  17 #include <linux/clk.h>
  18 #include <linux/delay.h>
  19 #include <linux/err.h>
  20 #include <linux/i2c.h>
  21 #include <linux/i2c-smbus.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/io.h>
  24 #include <linux/iopoll.h>
  25 #include <linux/mfd/syscon.h>
  26 #include <linux/module.h>
  27 #include <linux/of.h>
  28 #include <linux/of_address.h>
  29 #include <linux/of_platform.h>
  30 #include <linux/platform_device.h>
  31 #include <linux/pinctrl/consumer.h>
  32 #include <linux/pm_runtime.h>
  33 #include <linux/pm_wakeirq.h>
  34 #include <linux/regmap.h>
  35 #include <linux/reset.h>
  36 #include <linux/slab.h>
  37
  38 #include "i2c-stm32.h"
  39
  40 /* STM32F7 I2C registers */
  41 #define STM32F7_I2C_CR1                         0x00
  42 #define STM32F7_I2C_CR2                         0x04
  43 #define STM32F7_I2C_OAR1                        0x08
  44 #define STM32F7_I2C_OAR2                        0x0C
  45 #define STM32F7_I2C_PECR                        0x20
  46 #define STM32F7_I2C_TIMINGR                     0x10
  47 #define STM32F7_I2C_ISR                         0x18
  48 #define STM32F7_I2C_ICR                         0x1C
  49 #define STM32F7_I2C_RXDR                        0x24
  50 #define STM32F7_I2C_TXDR                        0x28
  51
  52 /* STM32F7 I2C control 1 */
  53 #define STM32F7_I2C_CR1_PECEN                   BIT(23)
  54 #define STM32F7_I2C_CR1_ALERTEN                 BIT(22)
  55 #define STM32F7_I2C_CR1_SMBHEN                  BIT(20)
  56 #define STM32F7_I2C_CR1_WUPEN                   BIT(18)
  57 #define STM32F7_I2C_CR1_SBC                     BIT(16)
  58 #define STM32F7_I2C_CR1_RXDMAEN                 BIT(15)
  59 #define STM32F7_I2C_CR1_TXDMAEN                 BIT(14)
  60 #define STM32F7_I2C_CR1_ANFOFF                  BIT(12)
  61 #define STM32F7_I2C_CR1_DNF_MASK                GENMASK(11, 8)
  62 #define STM32F7_I2C_CR1_DNF(n)                  (((n) & 0xf) << 8)
  63 #define STM32F7_I2C_CR1_ERRIE                   BIT(7)
  64 #define STM32F7_I2C_CR1_TCIE                    BIT(6)
  65 #define STM32F7_I2C_CR1_STOPIE                  BIT(5)
  66 #define STM32F7_I2C_CR1_NACKIE                  BIT(4)
  67 #define STM32F7_I2C_CR1_ADDRIE                  BIT(3)
  68 #define STM32F7_I2C_CR1_RXIE                    BIT(2)
  69 #define STM32F7_I2C_CR1_TXIE                    BIT(1)
  70 #define STM32F7_I2C_CR1_PE                      BIT(0)
  71 #define STM32F7_I2C_ALL_IRQ_MASK                (STM32F7_I2C_CR1_ERRIE \
  72                                                 | STM32F7_I2C_CR1_TCIE \
  73                                                 | STM32F7_I2C_CR1_STOPIE \
  74                                                 | STM32F7_I2C_CR1_NACKIE \
  75                                                 | STM32F7_I2C_CR1_RXIE \
  76                                                 | STM32F7_I2C_CR1_TXIE)
  77 #define STM32F7_I2C_XFER_IRQ_MASK               (STM32F7_I2C_CR1_TCIE \
  78                                                 | STM32F7_I2C_CR1_STOPIE \
  79                                                 | STM32F7_I2C_CR1_NACKIE \
  80                                                 | STM32F7_I2C_CR1_RXIE \
  81                                                 | STM32F7_I2C_CR1_TXIE)
  82
  83 /* STM32F7 I2C control 2 */
  84 #define STM32F7_I2C_CR2_PECBYTE                 BIT(26)
  85 #define STM32F7_I2C_CR2_RELOAD                  BIT(24)
  86 #define STM32F7_I2C_CR2_NBYTES_MASK             GENMASK(23, 16)
  87 #define STM32F7_I2C_CR2_NBYTES(n)               (((n) & 0xff) << 16)
  88 #define STM32F7_I2C_CR2_NACK                    BIT(15)
  89 #define STM32F7_I2C_CR2_STOP                    BIT(14)
  90 #define STM32F7_I2C_CR2_START                   BIT(13)
  91 #define STM32F7_I2C_CR2_HEAD10R                 BIT(12)
  92 #define STM32F7_I2C_CR2_ADD10                   BIT(11)
  93 #define STM32F7_I2C_CR2_RD_WRN                  BIT(10)
  94 #define STM32F7_I2C_CR2_SADD10_MASK             GENMASK(9, 0)
  95 #define STM32F7_I2C_CR2_SADD10(n)               (((n) & \
  96                                                 STM32F7_I2C_CR2_SADD10_MASK))
  97 #define STM32F7_I2C_CR2_SADD7_MASK              GENMASK(7, 1)
  98 #define STM32F7_I2C_CR2_SADD7(n)                (((n) & 0x7f) << 1)
  99
 100 /* STM32F7 I2C Own Address 1 */
 101 #define STM32F7_I2C_OAR1_OA1EN                  BIT(15)
 102 #define STM32F7_I2C_OAR1_OA1MODE                BIT(10)
 103 #define STM32F7_I2C_OAR1_OA1_10_MASK            GENMASK(9, 0)
 104 #define STM32F7_I2C_OAR1_OA1_10(n)              (((n) & \
 105                                                 STM32F7_I2C_OAR1_OA1_10_MASK))
 106 #define STM32F7_I2C_OAR1_OA1_7_MASK             GENMASK(7, 1)
 107 #define STM32F7_I2C_OAR1_OA1_7(n)               (((n) & 0x7f) << 1)
 108 #define STM32F7_I2C_OAR1_MASK                   (STM32F7_I2C_OAR1_OA1_7_MASK \
 109                                                 | STM32F7_I2C_OAR1_OA1_10_MASK \
 110                                                 | STM32F7_I2C_OAR1_OA1EN \
 111                                                 | STM32F7_I2C_OAR1_OA1MODE)
 112
 113 /* STM32F7 I2C Own Address 2 */
 114 #define STM32F7_I2C_OAR2_OA2EN                  BIT(15)
 115 #define STM32F7_I2C_OAR2_OA2MSK_MASK            GENMASK(10, 8)
 116 #define STM32F7_I2C_OAR2_OA2MSK(n)              (((n) & 0x7) << 8)
 117 #define STM32F7_I2C_OAR2_OA2_7_MASK             GENMASK(7, 1)
 118 #define STM32F7_I2C_OAR2_OA2_7(n)               (((n) & 0x7f) << 1)
 119 #define STM32F7_I2C_OAR2_MASK                   (STM32F7_I2C_OAR2_OA2MSK_MASK \
 120                                                 | STM32F7_I2C_OAR2_OA2_7_MASK \
 121                                                 | STM32F7_I2C_OAR2_OA2EN)
 122
 123 /* STM32F7 I2C Interrupt Status */
 124 #define STM32F7_I2C_ISR_ADDCODE_MASK            GENMASK(23, 17)
 125 #define STM32F7_I2C_ISR_ADDCODE_GET(n) \
 126                                 (((n) & STM32F7_I2C_ISR_ADDCODE_MASK) >> 17)
 127 #define STM32F7_I2C_ISR_DIR                     BIT(16)
 128 #define STM32F7_I2C_ISR_BUSY                    BIT(15)
 129 #define STM32F7_I2C_ISR_ALERT                   BIT(13)
 130 #define STM32F7_I2C_ISR_PECERR                  BIT(11)
 131 #define STM32F7_I2C_ISR_ARLO                    BIT(9)
 132 #define STM32F7_I2C_ISR_BERR                    BIT(8)
 133 #define STM32F7_I2C_ISR_TCR                     BIT(7)
 134 #define STM32F7_I2C_ISR_TC                      BIT(6)
 135 #define STM32F7_I2C_ISR_STOPF                   BIT(5)
 136 #define STM32F7_I2C_ISR_NACKF                   BIT(4)
 137 #define STM32F7_I2C_ISR_ADDR                    BIT(3)
 138 #define STM32F7_I2C_ISR_RXNE                    BIT(2)
 139 #define STM32F7_I2C_ISR_TXIS                    BIT(1)
 140 #define STM32F7_I2C_ISR_TXE                     BIT(0)
 141
 142 /* STM32F7 I2C Interrupt Clear */
 143 #define STM32F7_I2C_ICR_ALERTCF                 BIT(13)
 144 #define STM32F7_I2C_ICR_PECCF                   BIT(11)
 145 #define STM32F7_I2C_ICR_ARLOCF                  BIT(9)
 146 #define STM32F7_I2C_ICR_BERRCF                  BIT(8)
 147 #define STM32F7_I2C_ICR_STOPCF                  BIT(5)
 148 #define STM32F7_I2C_ICR_NACKCF                  BIT(4)
 149 #define STM32F7_I2C_ICR_ADDRCF                  BIT(3)
 150
 151 /* STM32F7 I2C Timing */
 152 #define STM32F7_I2C_TIMINGR_PRESC(n)            (((n) & 0xf) << 28)
 153 #define STM32F7_I2C_TIMINGR_SCLDEL(n)           (((n) & 0xf) << 20)
 154 #define STM32F7_I2C_TIMINGR_SDADEL(n)           (((n) & 0xf) << 16)
 155 #define STM32F7_I2C_TIMINGR_SCLH(n)             (((n) & 0xff) << 8)
 156 #define STM32F7_I2C_TIMINGR_SCLL(n)             ((n) & 0xff)
 157
 158 #define STM32F7_I2C_MAX_LEN                     0xff
 159 #define STM32F7_I2C_DMA_LEN_MIN                 0x16
 160 enum {
 161         STM32F7_SLAVE_HOSTNOTIFY,
 162         STM32F7_SLAVE_7_10_BITS_ADDR,
 163         STM32F7_SLAVE_7_BITS_ADDR,
 164         STM32F7_I2C_MAX_SLAVE
 165 };
 166
 167 #define STM32F7_I2C_DNF_DEFAULT                 0
 168 #define STM32F7_I2C_DNF_MAX                     15
 169
 170 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MIN     50      /* ns */
 171 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MAX     260     /* ns */
 172
 173 #define STM32F7_I2C_RISE_TIME_DEFAULT           25      /* ns */
 174 #define STM32F7_I2C_FALL_TIME_DEFAULT           10      /* ns */
 175
 176 #define STM32F7_PRESC_MAX                       BIT(4)
 177 #define STM32F7_SCLDEL_MAX                      BIT(4)
 178 #define STM32F7_SDADEL_MAX                      BIT(4)
 179 #define STM32F7_SCLH_MAX                        BIT(8)
 180 #define STM32F7_SCLL_MAX                        BIT(8)
 181
 182 #define STM32F7_AUTOSUSPEND_DELAY               (HZ / 100)
 183
 184 /**
 185  * struct stm32f7_i2c_regs - i2c f7 registers backup
 186  * @cr1: Control register 1
 187  * @cr2: Control register 2
 188  * @oar1: Own address 1 register
 189  * @oar2: Own address 2 register
 190  * @tmgr: Timing register
 191  */
 192 struct stm32f7_i2c_regs {
 193         u32 cr1;
 194         u32 cr2;
 195         u32 oar1;
 196         u32 oar2;
 197         u32 tmgr;
 198 };
 199
 200 /**
 201  * struct stm32f7_i2c_spec - private i2c specification timing
 202  * @rate: I2C bus speed (Hz)
 203  * @fall_max: Max fall time of both SDA and SCL signals (ns)
 204  * @rise_max: Max rise time of both SDA and SCL signals (ns)
 205  * @hddat_min: Min data hold time (ns)
 206  * @vddat_max: Max data valid time (ns)
 207  * @sudat_min: Min data setup time (ns)
 208  * @l_min: Min low period of the SCL clock (ns)
 209  * @h_min: Min high period of the SCL clock (ns)
 210  */
 211 struct stm32f7_i2c_spec {
 212         u32 rate;
 213         u32 fall_max;
 214         u32 rise_max;
 215         u32 hddat_min;
 216         u32 vddat_max;
 217         u32 sudat_min;
 218         u32 l_min;
 219         u32 h_min;
 220 };
 221
 222 /**
 223  * struct stm32f7_i2c_setup - private I2C timing setup parameters
 224  * @speed_freq: I2C speed frequency  (Hz)
 225  * @clock_src: I2C clock source frequency (Hz)
 226  * @rise_time: Rise time (ns)
 227  * @fall_time: Fall time (ns)
 228  * @fmp_clr_offset: Fast Mode Plus clear register offset from set register
 229  */
 230 struct stm32f7_i2c_setup {
 231         u32 speed_freq;
 232         u32 clock_src;
 233         u32 rise_time;
 234         u32 fall_time;
 235         u32 fmp_clr_offset;
 236 };
 237
 238 /**
 239  * struct stm32f7_i2c_timings - private I2C output parameters
 240  * @node: List entry
 241  * @presc: Prescaler value
 242  * @scldel: Data setup time
 243  * @sdadel: Data hold time
 244  * @sclh: SCL high period (master mode)
 245  * @scll: SCL low period (master mode)
 246  */
 247 struct stm32f7_i2c_timings {
 248         struct list_head node;
 249         u8 presc;
 250         u8 scldel;
 251         u8 sdadel;
 252         u8 sclh;
 253         u8 scll;
 254 };
 255
 256 /**
 257  * struct stm32f7_i2c_msg - client specific data
 258  * @addr: 8-bit or 10-bit slave addr, including r/w bit
 259  * @count: number of bytes to be transferred
 260  * @buf: data buffer
 261  * @result: result of the transfer
 262  * @stop: last I2C msg to be sent, i.e. STOP to be generated
 263  * @smbus: boolean to know if the I2C IP is used in SMBus mode
 264  * @size: type of SMBus protocol
 265  * @read_write: direction of SMBus protocol
 266  * SMBus block read and SMBus block write - block read process call protocols
 267  * @smbus_buf: buffer to be used for SMBus protocol transfer. It will
 268  * contain a maximum of 32 bytes of data + byte command + byte count + PEC
 269  * This buffer has to be 32-bit aligned to be compliant with memory address
 270  * register in DMA mode.
 271  */
 272 struct stm32f7_i2c_msg {
 273         u16 addr;
 274         u32 count;
 275         u8 *buf;
 276         int result;
 277         bool stop;
 278         bool smbus;
 279         int size;
 280         char read_write;
 281         u8 smbus_buf[I2C_SMBUS_BLOCK_MAX + 3] __aligned(4);
 282 };
 283
 284 /**
 285  * struct stm32f7_i2c_alert - SMBus alert specific data
 286  * @setup: platform data for the smbus_alert i2c client
 287  * @ara: I2C slave device used to respond to the SMBus Alert with Alert
 288  * Response Address
 289  */
 290 struct stm32f7_i2c_alert {
 291         struct i2c_smbus_alert_setup setup;
 292         struct i2c_client *ara;
 293 };
 294
 295 /**
 296  * struct stm32f7_i2c_dev - private data of the controller
 297  * @adap: I2C adapter for this controller
 298  * @dev: device for this controller
 299  * @base: virtual memory area
 300  * @complete: completion of I2C message
 301  * @clk: hw i2c clock
 302  * @bus_rate: I2C clock frequency of the controller
 303  * @msg: Pointer to data to be written
 304  * @msg_num: number of I2C messages to be executed
 305  * @msg_id: message identifiant
 306  * @f7_msg: customized i2c msg for driver usage
 307  * @setup: I2C timing input setup
 308  * @timing: I2C computed timings
 309  * @slave: list of slave devices registered on the I2C bus
 310  * @slave_running: slave device currently used
 311  * @backup_regs: backup of i2c controller registers (for suspend/resume)
 312  * @slave_dir: transfer direction for the current slave device
 313  * @master_mode: boolean to know in which mode the I2C is running (master or
 314  * slave)
 315  * @dma: dma data
 316  * @use_dma: boolean to know if dma is used in the current transfer
 317  * @regmap: holds SYSCFG phandle for Fast Mode Plus bits
 318  * @fmp_sreg: register address for setting Fast Mode Plus bits
 319  * @fmp_creg: register address for clearing Fast Mode Plus bits
 320  * @fmp_mask: mask for Fast Mode Plus bits in set register
 321  * @wakeup_src: boolean to know if the device is a wakeup source
 322  * @smbus_mode: states that the controller is configured in SMBus mode
 323  * @host_notify_client: SMBus host-notify client
 324  * @analog_filter: boolean to indicate enabling of the analog filter
 325  * @dnf_dt: value of digital filter requested via dt
 326  * @dnf: value of digital filter to apply
 327  * @alert: SMBus alert specific data
 328  */
 329 struct stm32f7_i2c_dev {
 330         struct i2c_adapter adap;
 331         struct device *dev;
 332         void __iomem *base;
 333         struct completion complete;
 334         struct clk *clk;
 335         unsigned int bus_rate;
 336         struct i2c_msg *msg;
 337         unsigned int msg_num;
 338         unsigned int msg_id;
 339         struct stm32f7_i2c_msg f7_msg;
 340         struct stm32f7_i2c_setup setup;
 341         struct stm32f7_i2c_timings timing;
 342         struct i2c_client *slave[STM32F7_I2C_MAX_SLAVE];
 343         struct i2c_client *slave_running;
 344         struct stm32f7_i2c_regs backup_regs;
 345         u32 slave_dir;
 346         bool master_mode;
 347         struct stm32_i2c_dma *dma;
 348         bool use_dma;
 349         struct regmap *regmap;
 350         u32 fmp_sreg;
 351         u32 fmp_creg;
 352         u32 fmp_mask;
 353         bool wakeup_src;
 354         bool smbus_mode;
 355         struct i2c_client *host_notify_client;
 356         bool analog_filter;
 357         u32 dnf_dt;
 358         u32 dnf;
 359         struct stm32f7_i2c_alert *alert;
 360 };
 361
 362 /*
 363  * All these values are coming from I2C Specification, Version 6.0, 4th of
 364  * April 2014.
 365  *
 366  * Table10. Characteristics of the SDA and SCL bus lines for Standard, Fast,
 367  * and Fast-mode Plus I2C-bus devices
 368  */
 369 static struct stm32f7_i2c_spec stm32f7_i2c_specs[] = {
 370         {
 371                 .rate = I2C_MAX_STANDARD_MODE_FREQ,
 372                 .fall_max = 300,
 373                 .rise_max = 1000,
 374                 .hddat_min = 0,
 375                 .vddat_max = 3450,
 376                 .sudat_min = 250,
 377                 .l_min = 4700,
 378                 .h_min = 4000,
 379         },
 380         {
 381                 .rate = I2C_MAX_FAST_MODE_FREQ,
 382                 .fall_max = 300,
 383                 .rise_max = 300,
 384                 .hddat_min = 0,
 385                 .vddat_max = 900,
 386                 .sudat_min = 100,
 387                 .l_min = 1300,
 388                 .h_min = 600,
 389         },
 390         {
 391                 .rate = I2C_MAX_FAST_MODE_PLUS_FREQ,
 392                 .fall_max = 100,
 393                 .rise_max = 120,
 394                 .hddat_min = 0,
 395                 .vddat_max = 450,
 396                 .sudat_min = 50,
 397                 .l_min = 500,
 398                 .h_min = 260,
 399         },
 400 };
 401
 402 static const struct stm32f7_i2c_setup stm32f7_setup = {
 403         .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
 404         .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
 405 };
 406
 407 static const struct stm32f7_i2c_setup stm32mp15_setup = {
 408         .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
 409         .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
 410         .fmp_clr_offset = 0x40,
 411 };
 412
 413 static const struct stm32f7_i2c_setup stm32mp13_setup = {
 414         .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
 415         .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
 416         .fmp_clr_offset = 0x4,
 417 };
 418
 419 static inline void stm32f7_i2c_set_bits(void __iomem *reg, u32 mask)
 420 {
 421         writel_relaxed(readl_relaxed(reg) | mask, reg);
 422 }
 423
 424 static inline void stm32f7_i2c_clr_bits(void __iomem *reg, u32 mask)
 425 {
 426         writel_relaxed(readl_relaxed(reg) & ~mask, reg);
 427 }
 428
 429 static void stm32f7_i2c_disable_irq(struct stm32f7_i2c_dev *i2c_dev, u32 mask)
 430 {
 431         stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, mask);
 432 }
 433
 434 static struct stm32f7_i2c_spec *stm32f7_get_specs(u32 rate)
 435 {
 436         int i;
 437
 438         for (i = 0; i < ARRAY_SIZE(stm32f7_i2c_specs); i++)
 439                 if (rate <= stm32f7_i2c_specs[i].rate)
 440                         return &stm32f7_i2c_specs[i];
 441
 442         return ERR_PTR(-EINVAL);
 443 }
 444
 445 #define RATE_MIN(rate)  ((rate) * 8 / 10)
 446 static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
 447                                       struct stm32f7_i2c_setup *setup,
 448                                       struct stm32f7_i2c_timings *output)
 449 {
 450         struct stm32f7_i2c_spec *specs;
 451         u32 p_prev = STM32F7_PRESC_MAX;
 452         u32 i2cclk = DIV_ROUND_CLOSEST(NSEC_PER_SEC,
 453                                        setup->clock_src);
 454         u32 i2cbus = DIV_ROUND_CLOSEST(NSEC_PER_SEC,
 455                                        setup->speed_freq);
 456         u32 clk_error_prev = i2cbus;
 457         u32 tsync;
 458         u32 af_delay_min, af_delay_max;
 459         u32 dnf_delay;
 460         u32 clk_min, clk_max;
 461         int sdadel_min, sdadel_max;
 462         int scldel_min;
 463         struct stm32f7_i2c_timings *v, *_v, *s;
 464         struct list_head solutions;
 465         u16 p, l, a, h;
 466         int ret = 0;
 467
 468         specs = stm32f7_get_specs(setup->speed_freq);
 469         if (specs == ERR_PTR(-EINVAL)) {
 470                 dev_err(i2c_dev->dev, "speed out of bound {%d}\n",
 471                         setup->speed_freq);
 472                 return -EINVAL;
 473         }
 474
 475         if ((setup->rise_time > specs->rise_max) ||
 476             (setup->fall_time > specs->fall_max)) {
 477                 dev_err(i2c_dev->dev,
 478                         "timings out of bound Rise{%d>%d}/Fall{%d>%d}\n",
 479                         setup->rise_time, specs->rise_max,
 480                         setup->fall_time, specs->fall_max);
 481                 return -EINVAL;
 482         }
 483
 484         i2c_dev->dnf = DIV_ROUND_CLOSEST(i2c_dev->dnf_dt, i2cclk);
 485         if (i2c_dev->dnf > STM32F7_I2C_DNF_MAX) {
 486                 dev_err(i2c_dev->dev,
 487                         "DNF out of bound %d/%d\n",
 488                         i2c_dev->dnf * i2cclk, STM32F7_I2C_DNF_MAX * i2cclk);
 489                 return -EINVAL;
 490         }
 491
 492         /*  Analog and Digital Filters */
 493         af_delay_min =
 494                 (i2c_dev->analog_filter ?
 495                  STM32F7_I2C_ANALOG_FILTER_DELAY_MIN : 0);
 496         af_delay_max =
 497                 (i2c_dev->analog_filter ?
 498                  STM32F7_I2C_ANALOG_FILTER_DELAY_MAX : 0);
 499         dnf_delay = i2c_dev->dnf * i2cclk;
 500
 501         sdadel_min = specs->hddat_min + setup->fall_time -
 502                 af_delay_min - (i2c_dev->dnf + 3) * i2cclk;
 503
 504         sdadel_max = specs->vddat_max - setup->rise_time -
 505                 af_delay_max - (i2c_dev->dnf + 4) * i2cclk;
 506
 507         scldel_min = setup->rise_time + specs->sudat_min;
 508
 509         if (sdadel_min < 0)
 510                 sdadel_min = 0;
 511         if (sdadel_max < 0)
 512                 sdadel_max = 0;
 513
 514         dev_dbg(i2c_dev->dev, "SDADEL(min/max): %i/%i, SCLDEL(Min): %i\n",
 515                 sdadel_min, sdadel_max, scldel_min);
 516
 517         INIT_LIST_HEAD(&solutions);
 518         /* Compute possible values for PRESC, SCLDEL and SDADEL */
 519         for (p = 0; p < STM32F7_PRESC_MAX; p++) {
 520                 for (l = 0; l < STM32F7_SCLDEL_MAX; l++) {
 521                         u32 scldel = (l + 1) * (p + 1) * i2cclk;
 522
 523                         if (scldel < scldel_min)
 524                                 continue;
 525
 526                         for (a = 0; a < STM32F7_SDADEL_MAX; a++) {
 527                                 u32 sdadel = (a * (p + 1) + 1) * i2cclk;
 528
 529                                 if (((sdadel >= sdadel_min) &&
 530                                      (sdadel <= sdadel_max)) &&
 531                                     (p != p_prev)) {
 532                                         v = kmalloc(sizeof(*v), GFP_KERNEL);
 533                                         if (!v) {
 534                                                 ret = -ENOMEM;
 535                                                 goto exit;
 536                                         }
 537
 538                                         v->presc = p;
 539                                         v->scldel = l;
 540                                         v->sdadel = a;
 541                                         p_prev = p;
 542
 543                                         list_add_tail(&v->node,
 544                                                       &solutions);
 545                                         break;
 546                                 }
 547                         }
 548
 549                         if (p_prev == p)
 550                                 break;
 551                 }
 552         }
 553
 554         if (list_empty(&solutions)) {
 555                 dev_err(i2c_dev->dev, "no Prescaler solution\n");
 556                 ret = -EPERM;
 557                 goto exit;
 558         }
 559
 560         tsync = af_delay_min + dnf_delay + (2 * i2cclk);
 561         s = NULL;
 562         clk_max = NSEC_PER_SEC / RATE_MIN(setup->speed_freq);
 563         clk_min = NSEC_PER_SEC / setup->speed_freq;
 564
 565         /*
 566          * Among Prescaler possibilities discovered above figures out SCL Low
 567          * and High Period. Provided:
 568          * - SCL Low Period has to be higher than SCL Clock Low Period
 569          *   defined by I2C Specification. I2C Clock has to be lower than
 570          *   (SCL Low Period - Analog/Digital filters) / 4.
 571          * - SCL High Period has to be lower than SCL Clock High Period
 572          *   defined by I2C Specification
 573          * - I2C Clock has to be lower than SCL High Period
 574          */
 575         list_for_each_entry(v, &solutions, node) {
 576                 u32 prescaler = (v->presc + 1) * i2cclk;
 577
 578                 for (l = 0; l < STM32F7_SCLL_MAX; l++) {
 579                         u32 tscl_l = (l + 1) * prescaler + tsync;
 580
 581                         if ((tscl_l < specs->l_min) ||
 582                             (i2cclk >=
 583                              ((tscl_l - af_delay_min - dnf_delay) / 4))) {
 584                                 continue;
 585                         }
 586
 587                         for (h = 0; h < STM32F7_SCLH_MAX; h++) {
 588                                 u32 tscl_h = (h + 1) * prescaler + tsync;
 589                                 u32 tscl = tscl_l + tscl_h +
 590                                         setup->rise_time + setup->fall_time;
 591
 592                                 if ((tscl >= clk_min) && (tscl <= clk_max) &&
 593                                     (tscl_h >= specs->h_min) &&
 594                                     (i2cclk < tscl_h)) {
 595                                         int clk_error = tscl - i2cbus;
 596
 597                                         if (clk_error < 0)
 598                                                 clk_error = -clk_error;
 599
 600                                         if (clk_error < clk_error_prev) {
 601                                                 clk_error_prev = clk_error;
 602                                                 v->scll = l;
 603                                                 v->sclh = h;
 604                                                 s = v;
 605                                         }
 606                                 }
 607                         }
 608                 }
 609         }
 610
 611         if (!s) {
 612                 dev_err(i2c_dev->dev, "no solution at all\n");
 613                 ret = -EPERM;
 614                 goto exit;
 615         }
 616
 617         output->presc = s->presc;
 618         output->scldel = s->scldel;
 619         output->sdadel = s->sdadel;
 620         output->scll = s->scll;
 621         output->sclh = s->sclh;
 622
 623         dev_dbg(i2c_dev->dev,
 624                 "Presc: %i, scldel: %i, sdadel: %i, scll: %i, sclh: %i\n",
 625                 output->presc,
 626                 output->scldel, output->sdadel,
 627                 output->scll, output->sclh);
 628
 629 exit:
 630         /* Release list and memory */
 631         list_for_each_entry_safe(v, _v, &solutions, node) {
 632                 list_del(&v->node);
 633                 kfree(v);
 634         }
 635
 636         return ret;
 637 }
 638
 639 static u32 stm32f7_get_lower_rate(u32 rate)
 640 {
 641         int i = ARRAY_SIZE(stm32f7_i2c_specs);
 642
 643         while (--i)
 644                 if (stm32f7_i2c_specs[i].rate < rate)
 645                         break;
 646
 647         return stm32f7_i2c_specs[i].rate;
 648 }
 649
 650 static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev,
 651                                     struct stm32f7_i2c_setup *setup)
 652 {
 653         struct i2c_timings timings, *t = &timings;
 654         int ret = 0;
 655
 656         t->bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ;
 657         t->scl_rise_ns = i2c_dev->setup.rise_time;
 658         t->scl_fall_ns = i2c_dev->setup.fall_time;
 659
 660         i2c_parse_fw_timings(i2c_dev->dev, t, false);
 661
 662         if (t->bus_freq_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) {
 663                 dev_err(i2c_dev->dev, "Invalid bus speed (%i>%i)\n",
 664                         t->bus_freq_hz, I2C_MAX_FAST_MODE_PLUS_FREQ);
 665                 return -EINVAL;
 666         }
 667
 668         setup->speed_freq = t->bus_freq_hz;
 669         i2c_dev->setup.rise_time = t->scl_rise_ns;
 670         i2c_dev->setup.fall_time = t->scl_fall_ns;
 671         i2c_dev->dnf_dt = t->digital_filter_width_ns;
 672         setup->clock_src = clk_get_rate(i2c_dev->clk);
 673
 674         if (!setup->clock_src) {
 675                 dev_err(i2c_dev->dev, "clock rate is 0\n");
 676                 return -EINVAL;
 677         }
 678
 679         if (!of_property_read_bool(i2c_dev->dev->of_node, "i2c-digital-filter"))
 680                 i2c_dev->dnf_dt = STM32F7_I2C_DNF_DEFAULT;
 681
 682         do {
 683                 ret = stm32f7_i2c_compute_timing(i2c_dev, setup,
 684                                                  &i2c_dev->timing);
 685                 if (ret) {
 686                         dev_err(i2c_dev->dev,
 687                                 "failed to compute I2C timings.\n");
 688                         if (setup->speed_freq <= I2C_MAX_STANDARD_MODE_FREQ)
 689                                 break;
 690                         setup->speed_freq =
 691                                 stm32f7_get_lower_rate(setup->speed_freq);
 692                         dev_warn(i2c_dev->dev,
 693                                  "downgrade I2C Speed Freq to (%i)\n",
 694                                  setup->speed_freq);
 695                 }
 696         } while (ret);
 697
 698         if (ret) {
 699                 dev_err(i2c_dev->dev, "Impossible to compute I2C timings.\n");
 700                 return ret;
 701         }
 702
 703         i2c_dev->analog_filter = of_property_read_bool(i2c_dev->dev->of_node,
 704                                                        "i2c-analog-filter");
 705
 706         dev_dbg(i2c_dev->dev, "I2C Speed(%i), Clk Source(%i)\n",
 707                 setup->speed_freq, setup->clock_src);
 708         dev_dbg(i2c_dev->dev, "I2C Rise(%i) and Fall(%i) Time\n",
 709                 setup->rise_time, setup->fall_time);
 710         dev_dbg(i2c_dev->dev, "I2C Analog Filter(%s), DNF(%i)\n",
 711                 (i2c_dev->analog_filter ? "On" : "Off"), i2c_dev->dnf);
 712
 713         i2c_dev->bus_rate = setup->speed_freq;
 714
 715         return 0;
 716 }
 717
 718 static void stm32f7_i2c_disable_dma_req(struct stm32f7_i2c_dev *i2c_dev)
 719 {
 720         void __iomem *base = i2c_dev->base;
 721         u32 mask = STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN;
 722
 723         stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
 724 }
 725
 726 static void stm32f7_i2c_dma_callback(void *arg)
 727 {
 728         struct stm32f7_i2c_dev *i2c_dev = (struct stm32f7_i2c_dev *)arg;
 729         struct stm32_i2c_dma *dma = i2c_dev->dma;
 730         struct device *dev = dma->chan_using->device->dev;
 731
 732         stm32f7_i2c_disable_dma_req(i2c_dev);
 733         dma_unmap_single(dev, dma->dma_buf, dma->dma_len, dma->dma_data_dir);
 734         complete(&dma->dma_complete);
 735 }
 736
 737 static void stm32f7_i2c_hw_config(struct stm32f7_i2c_dev *i2c_dev)
 738 {
 739         struct stm32f7_i2c_timings *t = &i2c_dev->timing;
 740         u32 timing = 0;
 741
 742         /* Timing settings */
 743         timing |= STM32F7_I2C_TIMINGR_PRESC(t->presc);
 744         timing |= STM32F7_I2C_TIMINGR_SCLDEL(t->scldel);
 745         timing |= STM32F7_I2C_TIMINGR_SDADEL(t->sdadel);
 746         timing |= STM32F7_I2C_TIMINGR_SCLH(t->sclh);
 747         timing |= STM32F7_I2C_TIMINGR_SCLL(t->scll);
 748         writel_relaxed(timing, i2c_dev->base + STM32F7_I2C_TIMINGR);
 749
 750         /* Configure the Analog Filter */
 751         if (i2c_dev->analog_filter)
 752                 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
 753                                      STM32F7_I2C_CR1_ANFOFF);
 754         else
 755                 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
 756                                      STM32F7_I2C_CR1_ANFOFF);
 757
 758         /* Program the Digital Filter */
 759         stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
 760                              STM32F7_I2C_CR1_DNF_MASK);
 761         stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
 762                              STM32F7_I2C_CR1_DNF(i2c_dev->dnf));
 763
 764         stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
 765                              STM32F7_I2C_CR1_PE);
 766 }
 767
 768 static void stm32f7_i2c_write_tx_data(struct stm32f7_i2c_dev *i2c_dev)
 769 {
 770         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
 771         void __iomem *base = i2c_dev->base;
 772
 773         if (f7_msg->count) {
 774                 writeb_relaxed(*f7_msg->buf++, base + STM32F7_I2C_TXDR);
 775                 f7_msg->count--;
 776         }
 777 }
 778
 779 static void stm32f7_i2c_read_rx_data(struct stm32f7_i2c_dev *i2c_dev)
 780 {
 781         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
 782         void __iomem *base = i2c_dev->base;
 783
 784         if (f7_msg->count) {
 785                 *f7_msg->buf++ = readb_relaxed(base + STM32F7_I2C_RXDR);
 786                 f7_msg->count--;
 787         } else {
 788                 /* Flush RX buffer has no data is expected */
 789                 readb_relaxed(base + STM32F7_I2C_RXDR);
 790         }
 791 }
 792
 793 static void stm32f7_i2c_reload(struct stm32f7_i2c_dev *i2c_dev)
 794 {
 795         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
 796         u32 cr2;
 797
 798         if (i2c_dev->use_dma)
 799                 f7_msg->count -= STM32F7_I2C_MAX_LEN;
 800
 801         cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
 802
 803         cr2 &= ~STM32F7_I2C_CR2_NBYTES_MASK;
 804         if (f7_msg->count > STM32F7_I2C_MAX_LEN) {
 805                 cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN);
 806         } else {
 807                 cr2 &= ~STM32F7_I2C_CR2_RELOAD;
 808                 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
 809         }
 810
 811         writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
 812 }
 813
 814 static void stm32f7_i2c_smbus_reload(struct stm32f7_i2c_dev *i2c_dev)
 815 {
 816         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
 817         u32 cr2;
 818         u8 *val;
 819
 820         /*
 821          * For I2C_SMBUS_BLOCK_DATA && I2C_SMBUS_BLOCK_PROC_CALL, the first
 822          * data received inform us how many data will follow.
 823          */
 824         stm32f7_i2c_read_rx_data(i2c_dev);
 825
 826         /*
 827          * Update NBYTES with the value read to continue the transfer
 828          */
 829         val = f7_msg->buf - sizeof(u8);
 830         f7_msg->count = *val;
 831         cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
 832         cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
 833         cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
 834         writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
 835 }
 836
 837 static void stm32f7_i2c_release_bus(struct i2c_adapter *i2c_adap)
 838 {
 839         struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
 840
 841         stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
 842                              STM32F7_I2C_CR1_PE);
 843
 844         stm32f7_i2c_hw_config(i2c_dev);
 845 }
 846
 847 static int stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev *i2c_dev)
 848 {
 849         u32 status;
 850         int ret;
 851
 852         ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F7_I2C_ISR,
 853                                          status,
 854                                          !(status & STM32F7_I2C_ISR_BUSY),
 855                                          10, 1000);
 856         if (!ret)
 857                 return 0;
 858
 859         stm32f7_i2c_release_bus(&i2c_dev->adap);
 860
 861         return -EBUSY;
 862 }
 863
 864 static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
 865                                  struct i2c_msg *msg)
 866 {
 867         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
 868         void __iomem *base = i2c_dev->base;
 869         u32 cr1, cr2;
 870         int ret;
 871
 872         f7_msg->addr = msg->addr;
 873         f7_msg->buf = msg->buf;
 874         f7_msg->count = msg->len;
 875         f7_msg->result = 0;
 876         f7_msg->stop = (i2c_dev->msg_id >= i2c_dev->msg_num - 1);
 877
 878         reinit_completion(&i2c_dev->complete);
 879
 880         cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
 881         cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
 882
 883         /* Set transfer direction */
 884         cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
 885         if (msg->flags & I2C_M_RD)
 886                 cr2 |= STM32F7_I2C_CR2_RD_WRN;
 887
 888         /* Set slave address */
 889         cr2 &= ~(STM32F7_I2C_CR2_HEAD10R | STM32F7_I2C_CR2_ADD10);
 890         if (msg->flags & I2C_M_TEN) {
 891                 cr2 &= ~STM32F7_I2C_CR2_SADD10_MASK;
 892                 cr2 |= STM32F7_I2C_CR2_SADD10(f7_msg->addr);
 893                 cr2 |= STM32F7_I2C_CR2_ADD10;
 894         } else {
 895                 cr2 &= ~STM32F7_I2C_CR2_SADD7_MASK;
 896                 cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
 897         }
 898
 899         /* Set nb bytes to transfer and reload if needed */
 900         cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
 901         if (f7_msg->count > STM32F7_I2C_MAX_LEN) {
 902                 cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN);
 903                 cr2 |= STM32F7_I2C_CR2_RELOAD;
 904         } else {
 905                 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
 906         }
 907
 908         /* Enable NACK, STOP, error and transfer complete interrupts */
 909         cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE |
 910                 STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE;
 911
 912         /* Clear DMA req and TX/RX interrupt */
 913         cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
 914                         STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
 915
 916         /* Configure DMA or enable RX/TX interrupt */
 917         i2c_dev->use_dma = false;
 918         if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) {
 919                 ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
 920                                               msg->flags & I2C_M_RD,
 921                                               f7_msg->count, f7_msg->buf,
 922                                               stm32f7_i2c_dma_callback,
 923                                               i2c_dev);
 924                 if (!ret)
 925                         i2c_dev->use_dma = true;
 926                 else
 927                         dev_warn(i2c_dev->dev, "can't use DMA\n");
 928         }
 929
 930         if (!i2c_dev->use_dma) {
 931                 if (msg->flags & I2C_M_RD)
 932                         cr1 |= STM32F7_I2C_CR1_RXIE;
 933                 else
 934                         cr1 |= STM32F7_I2C_CR1_TXIE;
 935         } else {
 936                 if (msg->flags & I2C_M_RD)
 937                         cr1 |= STM32F7_I2C_CR1_RXDMAEN;
 938                 else
 939                         cr1 |= STM32F7_I2C_CR1_TXDMAEN;
 940         }
 941
 942         /* Configure Start/Repeated Start */
 943         cr2 |= STM32F7_I2C_CR2_START;
 944
 945         i2c_dev->master_mode = true;
 946
 947         /* Write configurations registers */
 948         writel_relaxed(cr1, base + STM32F7_I2C_CR1);
 949         writel_relaxed(cr2, base + STM32F7_I2C_CR2);
 950 }
 951
 952 static int stm32f7_i2c_smbus_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
 953                                       unsigned short flags, u8 command,
 954                                       union i2c_smbus_data *data)
 955 {
 956         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
 957         struct device *dev = i2c_dev->dev;
 958         void __iomem *base = i2c_dev->base;
 959         u32 cr1, cr2;
 960         int i, ret;
 961
 962         f7_msg->result = 0;
 963         reinit_completion(&i2c_dev->complete);
 964
 965         cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
 966         cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
 967
 968         /* Set transfer direction */
 969         cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
 970         if (f7_msg->read_write)
 971                 cr2 |= STM32F7_I2C_CR2_RD_WRN;
 972
 973         /* Set slave address */
 974         cr2 &= ~(STM32F7_I2C_CR2_ADD10 | STM32F7_I2C_CR2_SADD7_MASK);
 975         cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
 976
 977         f7_msg->smbus_buf[0] = command;
 978         switch (f7_msg->size) {
 979         case I2C_SMBUS_QUICK:
 980                 f7_msg->stop = true;
 981                 f7_msg->count = 0;
 982                 break;
 983         case I2C_SMBUS_BYTE:
 984                 f7_msg->stop = true;
 985                 f7_msg->count = 1;
 986                 break;
 987         case I2C_SMBUS_BYTE_DATA:
 988                 if (f7_msg->read_write) {
 989                         f7_msg->stop = false;
 990                         f7_msg->count = 1;
 991                         cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
 992                 } else {
 993                         f7_msg->stop = true;
 994                         f7_msg->count = 2;
 995                         f7_msg->smbus_buf[1] = data->byte;
 996                 }
 997                 break;
 998         case I2C_SMBUS_WORD_DATA:
 999                 if (f7_msg->read_write) {
1000                         f7_msg->stop = false;
1001                         f7_msg->count = 1;
1002                         cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1003                 } else {
1004                         f7_msg->stop = true;
1005                         f7_msg->count = 3;
1006                         f7_msg->smbus_buf[1] = data->word & 0xff;
1007                         f7_msg->smbus_buf[2] = data->word >> 8;
1008                 }
1009                 break;
1010         case I2C_SMBUS_BLOCK_DATA:
1011                 if (f7_msg->read_write) {
1012                         f7_msg->stop = false;
1013                         f7_msg->count = 1;
1014                         cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1015                 } else {
1016                         f7_msg->stop = true;
1017                         if (data->block[0] > I2C_SMBUS_BLOCK_MAX ||
1018                             !data->block[0]) {
1019                                 dev_err(dev, "Invalid block write size %d\n",
1020                                         data->block[0]);
1021                                 return -EINVAL;
1022                         }
1023                         f7_msg->count = data->block[0] + 2;
1024                         for (i = 1; i < f7_msg->count; i++)
1025                                 f7_msg->smbus_buf[i] = data->block[i - 1];
1026                 }
1027                 break;
1028         case I2C_SMBUS_PROC_CALL:
1029                 f7_msg->stop = false;
1030                 f7_msg->count = 3;
1031                 f7_msg->smbus_buf[1] = data->word & 0xff;
1032                 f7_msg->smbus_buf[2] = data->word >> 8;
1033                 cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1034                 f7_msg->read_write = I2C_SMBUS_READ;
1035                 break;
1036         case I2C_SMBUS_BLOCK_PROC_CALL:
1037                 f7_msg->stop = false;
1038                 if (data->block[0] > I2C_SMBUS_BLOCK_MAX - 1) {
1039                         dev_err(dev, "Invalid block write size %d\n",
1040                                 data->block[0]);
1041                         return -EINVAL;
1042                 }
1043                 f7_msg->count = data->block[0] + 2;
1044                 for (i = 1; i < f7_msg->count; i++)
1045                         f7_msg->smbus_buf[i] = data->block[i - 1];
1046                 cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
1047                 f7_msg->read_write = I2C_SMBUS_READ;
1048                 break;
1049         case I2C_SMBUS_I2C_BLOCK_DATA:
1050                 /* Rely on emulated i2c transfer (through master_xfer) */
1051                 return -EOPNOTSUPP;
1052         default:
1053                 dev_err(dev, "Unsupported smbus protocol %d\n", f7_msg->size);
1054                 return -EOPNOTSUPP;
1055         }
1056
1057         f7_msg->buf = f7_msg->smbus_buf;
1058
1059         /* Configure PEC */
1060         if ((flags & I2C_CLIENT_PEC) && f7_msg->size != I2C_SMBUS_QUICK) {
1061                 cr1 |= STM32F7_I2C_CR1_PECEN;
1062                 cr2 |= STM32F7_I2C_CR2_PECBYTE;
1063                 if (!f7_msg->read_write)
1064                         f7_msg->count++;
1065         } else {
1066                 cr1 &= ~STM32F7_I2C_CR1_PECEN;
1067                 cr2 &= ~STM32F7_I2C_CR2_PECBYTE;
1068         }
1069
1070         /* Set number of bytes to be transferred */
1071         cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
1072         cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
1073
1074         /* Enable NACK, STOP, error and transfer complete interrupts */
1075         cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE |
1076                 STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE;
1077
1078         /* Clear DMA req and TX/RX interrupt */
1079         cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
1080                         STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
1081
1082         /* Configure DMA or enable RX/TX interrupt */
1083         i2c_dev->use_dma = false;
1084         if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) {
1085                 ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
1086                                               cr2 & STM32F7_I2C_CR2_RD_WRN,
1087                                               f7_msg->count, f7_msg->buf,
1088                                               stm32f7_i2c_dma_callback,
1089                                               i2c_dev);
1090                 if (!ret)
1091                         i2c_dev->use_dma = true;
1092                 else
1093                         dev_warn(i2c_dev->dev, "can't use DMA\n");
1094         }
1095
1096         if (!i2c_dev->use_dma) {
1097                 if (cr2 & STM32F7_I2C_CR2_RD_WRN)
1098                         cr1 |= STM32F7_I2C_CR1_RXIE;
1099                 else
1100                         cr1 |= STM32F7_I2C_CR1_TXIE;
1101         } else {
1102                 if (cr2 & STM32F7_I2C_CR2_RD_WRN)
1103                         cr1 |= STM32F7_I2C_CR1_RXDMAEN;
1104                 else
1105                         cr1 |= STM32F7_I2C_CR1_TXDMAEN;
1106         }
1107
1108         /* Set Start bit */
1109         cr2 |= STM32F7_I2C_CR2_START;
1110
1111         i2c_dev->master_mode = true;
1112
1113         /* Write configurations registers */
1114         writel_relaxed(cr1, base + STM32F7_I2C_CR1);
1115         writel_relaxed(cr2, base + STM32F7_I2C_CR2);
1116
1117         return 0;
1118 }
1119
1120 static void stm32f7_i2c_smbus_rep_start(struct stm32f7_i2c_dev *i2c_dev)
1121 {
1122         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1123         void __iomem *base = i2c_dev->base;
1124         u32 cr1, cr2;
1125         int ret;
1126
1127         cr2 = readl_relaxed(base + STM32F7_I2C_CR2);
1128         cr1 = readl_relaxed(base + STM32F7_I2C_CR1);
1129
1130         /* Set transfer direction */
1131         cr2 |= STM32F7_I2C_CR2_RD_WRN;
1132
1133         switch (f7_msg->size) {
1134         case I2C_SMBUS_BYTE_DATA:
1135                 f7_msg->count = 1;
1136                 break;
1137         case I2C_SMBUS_WORD_DATA:
1138         case I2C_SMBUS_PROC_CALL:
1139                 f7_msg->count = 2;
1140                 break;
1141         case I2C_SMBUS_BLOCK_DATA:
1142         case I2C_SMBUS_BLOCK_PROC_CALL:
1143                 f7_msg->count = 1;
1144                 cr2 |= STM32F7_I2C_CR2_RELOAD;
1145                 break;
1146         }
1147
1148         f7_msg->buf = f7_msg->smbus_buf;
1149         f7_msg->stop = true;
1150
1151         /* Add one byte for PEC if needed */
1152         if (cr1 & STM32F7_I2C_CR1_PECEN)
1153                 f7_msg->count++;
1154
1155         /* Set number of bytes to be transferred */
1156         cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK);
1157         cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count);
1158
1159         /*
1160          * Configure RX/TX interrupt:
1161          */
1162         cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE);
1163         cr1 |= STM32F7_I2C_CR1_RXIE;
1164
1165         /*
1166          * Configure DMA or enable RX/TX interrupt:
1167          * For I2C_SMBUS_BLOCK_DATA and I2C_SMBUS_BLOCK_PROC_CALL we don't use
1168          * dma as we don't know in advance how many data will be received
1169          */
1170         cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE |
1171                  STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN);
1172
1173         i2c_dev->use_dma = false;
1174         if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN &&
1175             f7_msg->size != I2C_SMBUS_BLOCK_DATA &&
1176             f7_msg->size != I2C_SMBUS_BLOCK_PROC_CALL) {
1177                 ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma,
1178                                               cr2 & STM32F7_I2C_CR2_RD_WRN,
1179                                               f7_msg->count, f7_msg->buf,
1180                                               stm32f7_i2c_dma_callback,
1181                                               i2c_dev);
1182
1183                 if (!ret)
1184                         i2c_dev->use_dma = true;
1185                 else
1186                         dev_warn(i2c_dev->dev, "can't use DMA\n");
1187         }
1188
1189         if (!i2c_dev->use_dma)
1190                 cr1 |= STM32F7_I2C_CR1_RXIE;
1191         else
1192                 cr1 |= STM32F7_I2C_CR1_RXDMAEN;
1193
1194         /* Configure Repeated Start */
1195         cr2 |= STM32F7_I2C_CR2_START;
1196
1197         /* Write configurations registers */
1198         writel_relaxed(cr1, base + STM32F7_I2C_CR1);
1199         writel_relaxed(cr2, base + STM32F7_I2C_CR2);
1200 }
1201
1202 static int stm32f7_i2c_smbus_check_pec(struct stm32f7_i2c_dev *i2c_dev)
1203 {
1204         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1205         u8 count, internal_pec, received_pec;
1206
1207         internal_pec = readl_relaxed(i2c_dev->base + STM32F7_I2C_PECR);
1208
1209         switch (f7_msg->size) {
1210         case I2C_SMBUS_BYTE:
1211         case I2C_SMBUS_BYTE_DATA:
1212                 received_pec = f7_msg->smbus_buf[1];
1213                 break;
1214         case I2C_SMBUS_WORD_DATA:
1215         case I2C_SMBUS_PROC_CALL:
1216                 received_pec = f7_msg->smbus_buf[2];
1217                 break;
1218         case I2C_SMBUS_BLOCK_DATA:
1219         case I2C_SMBUS_BLOCK_PROC_CALL:
1220                 count = f7_msg->smbus_buf[0];
1221                 received_pec = f7_msg->smbus_buf[count];
1222                 break;
1223         default:
1224                 dev_err(i2c_dev->dev, "Unsupported smbus protocol for PEC\n");
1225                 return -EINVAL;
1226         }
1227
1228         if (internal_pec != received_pec) {
1229                 dev_err(i2c_dev->dev, "Bad PEC 0x%02x vs. 0x%02x\n",
1230                         internal_pec, received_pec);
1231                 return -EBADMSG;
1232         }
1233
1234         return 0;
1235 }
1236
1237 static bool stm32f7_i2c_is_addr_match(struct i2c_client *slave, u32 addcode)
1238 {
1239         u32 addr;
1240
1241         if (!slave)
1242                 return false;
1243
1244         if (slave->flags & I2C_CLIENT_TEN) {
1245                 /*
1246                  * For 10-bit addr, addcode = 11110XY with
1247                  * X = Bit 9 of slave address
1248                  * Y = Bit 8 of slave address
1249                  */
1250                 addr = slave->addr >> 8;
1251                 addr |= 0x78;
1252                 if (addr == addcode)
1253                         return true;
1254         } else {
1255                 addr = slave->addr & 0x7f;
1256                 if (addr == addcode)
1257                         return true;
1258         }
1259
1260         return false;
1261 }
1262
1263 static void stm32f7_i2c_slave_start(struct stm32f7_i2c_dev *i2c_dev)
1264 {
1265         struct i2c_client *slave = i2c_dev->slave_running;
1266         void __iomem *base = i2c_dev->base;
1267         u32 mask;
1268         u8 value = 0;
1269
1270         if (i2c_dev->slave_dir) {
1271                 /* Notify i2c slave that new read transfer is starting */
1272                 i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value);
1273
1274                 /*
1275                  * Disable slave TX config in case of I2C combined message
1276                  * (I2C Write followed by I2C Read)
1277                  */
1278                 mask = STM32F7_I2C_CR2_RELOAD;
1279                 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, mask);
1280                 mask = STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE |
1281                        STM32F7_I2C_CR1_TCIE;
1282                 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
1283
1284                 /* Enable TX empty, STOP, NACK interrupts */
1285                 mask =  STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE |
1286                         STM32F7_I2C_CR1_TXIE;
1287                 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1288
1289                 /* Write 1st data byte */
1290                 writel_relaxed(value, base + STM32F7_I2C_TXDR);
1291         } else {
1292                 /* Notify i2c slave that new write transfer is starting */
1293                 i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value);
1294
1295                 /* Set reload mode to be able to ACK/NACK each received byte */
1296                 mask = STM32F7_I2C_CR2_RELOAD;
1297                 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
1298
1299                 /*
1300                  * Set STOP, NACK, RX empty and transfer complete interrupts.*
1301                  * Set Slave Byte Control to be able to ACK/NACK each data
1302                  * byte received
1303                  */
1304                 mask =  STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE |
1305                         STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE |
1306                         STM32F7_I2C_CR1_TCIE;
1307                 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1308         }
1309 }
1310
1311 static void stm32f7_i2c_slave_addr(struct stm32f7_i2c_dev *i2c_dev)
1312 {
1313         void __iomem *base = i2c_dev->base;
1314         u32 isr, addcode, dir, mask;
1315         int i;
1316
1317         isr = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1318         addcode = STM32F7_I2C_ISR_ADDCODE_GET(isr);
1319         dir = isr & STM32F7_I2C_ISR_DIR;
1320
1321         for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1322                 if (stm32f7_i2c_is_addr_match(i2c_dev->slave[i], addcode)) {
1323                         i2c_dev->slave_running = i2c_dev->slave[i];
1324                         i2c_dev->slave_dir = dir;
1325
1326                         /* Start I2C slave processing */
1327                         stm32f7_i2c_slave_start(i2c_dev);
1328
1329                         /* Clear ADDR flag */
1330                         mask = STM32F7_I2C_ICR_ADDRCF;
1331                         writel_relaxed(mask, base + STM32F7_I2C_ICR);
1332                         break;
1333                 }
1334         }
1335 }
1336
1337 static int stm32f7_i2c_get_slave_id(struct stm32f7_i2c_dev *i2c_dev,
1338                                     struct i2c_client *slave, int *id)
1339 {
1340         int i;
1341
1342         for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1343                 if (i2c_dev->slave[i] == slave) {
1344                         *id = i;
1345                         return 0;
1346                 }
1347         }
1348
1349         dev_err(i2c_dev->dev, "Slave 0x%x not registered\n", slave->addr);
1350
1351         return -ENODEV;
1352 }
1353
1354 static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev,
1355                                          struct i2c_client *slave, int *id)
1356 {
1357         struct device *dev = i2c_dev->dev;
1358         int i;
1359
1360         /*
1361          * slave[STM32F7_SLAVE_HOSTNOTIFY] support only SMBus Host address (0x8)
1362          * slave[STM32F7_SLAVE_7_10_BITS_ADDR] supports 7-bit and 10-bit slave address
1363          * slave[STM32F7_SLAVE_7_BITS_ADDR] supports 7-bit slave address only
1364          */
1365         if (i2c_dev->smbus_mode && (slave->addr == 0x08)) {
1366                 if (i2c_dev->slave[STM32F7_SLAVE_HOSTNOTIFY])
1367                         goto fail;
1368                 *id = STM32F7_SLAVE_HOSTNOTIFY;
1369                 return 0;
1370         }
1371
1372         for (i = STM32F7_I2C_MAX_SLAVE - 1; i > STM32F7_SLAVE_HOSTNOTIFY; i--) {
1373                 if ((i == STM32F7_SLAVE_7_BITS_ADDR) &&
1374                     (slave->flags & I2C_CLIENT_TEN))
1375                         continue;
1376                 if (!i2c_dev->slave[i]) {
1377                         *id = i;
1378                         return 0;
1379                 }
1380         }
1381
1382 fail:
1383         dev_err(dev, "Slave 0x%x could not be registered\n", slave->addr);
1384
1385         return -EINVAL;
1386 }
1387
1388 static bool stm32f7_i2c_is_slave_registered(struct stm32f7_i2c_dev *i2c_dev)
1389 {
1390         int i;
1391
1392         for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1393                 if (i2c_dev->slave[i])
1394                         return true;
1395         }
1396
1397         return false;
1398 }
1399
1400 static bool stm32f7_i2c_is_slave_busy(struct stm32f7_i2c_dev *i2c_dev)
1401 {
1402         int i, busy;
1403
1404         busy = 0;
1405         for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
1406                 if (i2c_dev->slave[i])
1407                         busy++;
1408         }
1409
1410         return i == busy;
1411 }
1412
1413 static irqreturn_t stm32f7_i2c_slave_isr_event(struct stm32f7_i2c_dev *i2c_dev)
1414 {
1415         void __iomem *base = i2c_dev->base;
1416         u32 cr2, status, mask;
1417         u8 val;
1418         int ret;
1419
1420         status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1421
1422         /* Slave transmitter mode */
1423         if (status & STM32F7_I2C_ISR_TXIS) {
1424                 i2c_slave_event(i2c_dev->slave_running,
1425                                 I2C_SLAVE_READ_PROCESSED,
1426                                 &val);
1427
1428                 /* Write data byte */
1429                 writel_relaxed(val, base + STM32F7_I2C_TXDR);
1430         }
1431
1432         /* Transfer Complete Reload for Slave receiver mode */
1433         if (status & STM32F7_I2C_ISR_TCR || status & STM32F7_I2C_ISR_RXNE) {
1434                 /*
1435                  * Read data byte then set NBYTES to receive next byte or NACK
1436                  * the current received byte
1437                  */
1438                 val = readb_relaxed(i2c_dev->base + STM32F7_I2C_RXDR);
1439                 ret = i2c_slave_event(i2c_dev->slave_running,
1440                                       I2C_SLAVE_WRITE_RECEIVED,
1441                                       &val);
1442                 if (!ret) {
1443                         cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
1444                         cr2 |= STM32F7_I2C_CR2_NBYTES(1);
1445                         writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
1446                 } else {
1447                         mask = STM32F7_I2C_CR2_NACK;
1448                         stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
1449                 }
1450         }
1451
1452         /* NACK received */
1453         if (status & STM32F7_I2C_ISR_NACKF) {
1454                 dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__);
1455                 writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
1456         }
1457
1458         /* STOP received */
1459         if (status & STM32F7_I2C_ISR_STOPF) {
1460                 /* Disable interrupts */
1461                 stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_XFER_IRQ_MASK);
1462
1463                 if (i2c_dev->slave_dir) {
1464                         /*
1465                          * Flush TX buffer in order to not used the byte in
1466                          * TXDR for the next transfer
1467                          */
1468                         mask = STM32F7_I2C_ISR_TXE;
1469                         stm32f7_i2c_set_bits(base + STM32F7_I2C_ISR, mask);
1470                 }
1471
1472                 /* Clear STOP flag */
1473                 writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR);
1474
1475                 /* Notify i2c slave that a STOP flag has been detected */
1476                 i2c_slave_event(i2c_dev->slave_running, I2C_SLAVE_STOP, &val);
1477
1478                 i2c_dev->slave_running = NULL;
1479         }
1480
1481         /* Address match received */
1482         if (status & STM32F7_I2C_ISR_ADDR)
1483                 stm32f7_i2c_slave_addr(i2c_dev);
1484
1485         return IRQ_HANDLED;
1486 }
1487
1488 static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data)
1489 {
1490         struct stm32f7_i2c_dev *i2c_dev = data;
1491         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1492         struct stm32_i2c_dma *dma = i2c_dev->dma;
1493         void __iomem *base = i2c_dev->base;
1494         u32 status, mask;
1495         int ret = IRQ_HANDLED;
1496
1497         /* Check if the interrupt if for a slave device */
1498         if (!i2c_dev->master_mode) {
1499                 ret = stm32f7_i2c_slave_isr_event(i2c_dev);
1500                 return ret;
1501         }
1502
1503         status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1504
1505         /* Tx empty */
1506         if (status & STM32F7_I2C_ISR_TXIS)
1507                 stm32f7_i2c_write_tx_data(i2c_dev);
1508
1509         /* RX not empty */
1510         if (status & STM32F7_I2C_ISR_RXNE)
1511                 stm32f7_i2c_read_rx_data(i2c_dev);
1512
1513         /* NACK received */
1514         if (status & STM32F7_I2C_ISR_NACKF) {
1515                 dev_dbg(i2c_dev->dev, "<%s>: Receive NACK (addr %x)\n",
1516                         __func__, f7_msg->addr);
1517                 writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
1518                 if (i2c_dev->use_dma) {
1519                         stm32f7_i2c_disable_dma_req(i2c_dev);
1520                         dmaengine_terminate_async(dma->chan_using);
1521                 }
1522                 f7_msg->result = -ENXIO;
1523         }
1524
1525         /* STOP detection flag */
1526         if (status & STM32F7_I2C_ISR_STOPF) {
1527                 /* Disable interrupts */
1528                 if (stm32f7_i2c_is_slave_registered(i2c_dev))
1529                         mask = STM32F7_I2C_XFER_IRQ_MASK;
1530                 else
1531                         mask = STM32F7_I2C_ALL_IRQ_MASK;
1532                 stm32f7_i2c_disable_irq(i2c_dev, mask);
1533
1534                 /* Clear STOP flag */
1535                 writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR);
1536
1537                 if (i2c_dev->use_dma && !f7_msg->result) {
1538                         ret = IRQ_WAKE_THREAD;
1539                 } else {
1540                         i2c_dev->master_mode = false;
1541                         complete(&i2c_dev->complete);
1542                 }
1543         }
1544
1545         /* Transfer complete */
1546         if (status & STM32F7_I2C_ISR_TC) {
1547                 if (f7_msg->stop) {
1548                         mask = STM32F7_I2C_CR2_STOP;
1549                         stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask);
1550                 } else if (i2c_dev->use_dma && !f7_msg->result) {
1551                         ret = IRQ_WAKE_THREAD;
1552                 } else if (f7_msg->smbus) {
1553                         stm32f7_i2c_smbus_rep_start(i2c_dev);
1554                 } else {
1555                         i2c_dev->msg_id++;
1556                         i2c_dev->msg++;
1557                         stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg);
1558                 }
1559         }
1560
1561         if (status & STM32F7_I2C_ISR_TCR) {
1562                 if (f7_msg->smbus)
1563                         stm32f7_i2c_smbus_reload(i2c_dev);
1564                 else
1565                         stm32f7_i2c_reload(i2c_dev);
1566         }
1567
1568         return ret;
1569 }
1570
1571 static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data)
1572 {
1573         struct stm32f7_i2c_dev *i2c_dev = data;
1574         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1575         struct stm32_i2c_dma *dma = i2c_dev->dma;
1576         u32 status;
1577         int ret;
1578
1579         /*
1580          * Wait for dma transfer completion before sending next message or
1581          * notity the end of xfer to the client
1582          */
1583         ret = wait_for_completion_timeout(&i2c_dev->dma->dma_complete, HZ);
1584         if (!ret) {
1585                 dev_dbg(i2c_dev->dev, "<%s>: Timed out\n", __func__);
1586                 stm32f7_i2c_disable_dma_req(i2c_dev);
1587                 dmaengine_terminate_async(dma->chan_using);
1588                 f7_msg->result = -ETIMEDOUT;
1589         }
1590
1591         status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1592
1593         if (status & STM32F7_I2C_ISR_TC) {
1594                 if (f7_msg->smbus) {
1595                         stm32f7_i2c_smbus_rep_start(i2c_dev);
1596                 } else {
1597                         i2c_dev->msg_id++;
1598                         i2c_dev->msg++;
1599                         stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg);
1600                 }
1601         } else {
1602                 i2c_dev->master_mode = false;
1603                 complete(&i2c_dev->complete);
1604         }
1605
1606         return IRQ_HANDLED;
1607 }
1608
1609 static irqreturn_t stm32f7_i2c_isr_error(int irq, void *data)
1610 {
1611         struct stm32f7_i2c_dev *i2c_dev = data;
1612         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1613         void __iomem *base = i2c_dev->base;
1614         struct device *dev = i2c_dev->dev;
1615         struct stm32_i2c_dma *dma = i2c_dev->dma;
1616         u32 status;
1617
1618         status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR);
1619
1620         /* Bus error */
1621         if (status & STM32F7_I2C_ISR_BERR) {
1622                 dev_err(dev, "<%s>: Bus error accessing addr 0x%x\n",
1623                         __func__, f7_msg->addr);
1624                 writel_relaxed(STM32F7_I2C_ICR_BERRCF, base + STM32F7_I2C_ICR);
1625                 stm32f7_i2c_release_bus(&i2c_dev->adap);
1626                 f7_msg->result = -EIO;
1627         }
1628
1629         /* Arbitration loss */
1630         if (status & STM32F7_I2C_ISR_ARLO) {
1631                 dev_dbg(dev, "<%s>: Arbitration loss accessing addr 0x%x\n",
1632                         __func__, f7_msg->addr);
1633                 writel_relaxed(STM32F7_I2C_ICR_ARLOCF, base + STM32F7_I2C_ICR);
1634                 f7_msg->result = -EAGAIN;
1635         }
1636
1637         if (status & STM32F7_I2C_ISR_PECERR) {
1638                 dev_err(dev, "<%s>: PEC error in reception accessing addr 0x%x\n",
1639                         __func__, f7_msg->addr);
1640                 writel_relaxed(STM32F7_I2C_ICR_PECCF, base + STM32F7_I2C_ICR);
1641                 f7_msg->result = -EINVAL;
1642         }
1643
1644         if (status & STM32F7_I2C_ISR_ALERT) {
1645                 dev_dbg(dev, "<%s>: SMBus alert received\n", __func__);
1646                 writel_relaxed(STM32F7_I2C_ICR_ALERTCF, base + STM32F7_I2C_ICR);
1647                 i2c_handle_smbus_alert(i2c_dev->alert->ara);
1648                 return IRQ_HANDLED;
1649         }
1650
1651         if (!i2c_dev->slave_running) {
1652                 u32 mask;
1653                 /* Disable interrupts */
1654                 if (stm32f7_i2c_is_slave_registered(i2c_dev))
1655                         mask = STM32F7_I2C_XFER_IRQ_MASK;
1656                 else
1657                         mask = STM32F7_I2C_ALL_IRQ_MASK;
1658                 stm32f7_i2c_disable_irq(i2c_dev, mask);
1659         }
1660
1661         /* Disable dma */
1662         if (i2c_dev->use_dma) {
1663                 stm32f7_i2c_disable_dma_req(i2c_dev);
1664                 dmaengine_terminate_async(dma->chan_using);
1665         }
1666
1667         i2c_dev->master_mode = false;
1668         complete(&i2c_dev->complete);
1669
1670         return IRQ_HANDLED;
1671 }
1672
1673 static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
1674                             struct i2c_msg msgs[], int num)
1675 {
1676         struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
1677         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1678         struct stm32_i2c_dma *dma = i2c_dev->dma;
1679         unsigned long time_left;
1680         int ret;
1681
1682         i2c_dev->msg = msgs;
1683         i2c_dev->msg_num = num;
1684         i2c_dev->msg_id = 0;
1685         f7_msg->smbus = false;
1686
1687         ret = pm_runtime_resume_and_get(i2c_dev->dev);
1688         if (ret < 0)
1689                 return ret;
1690
1691         ret = stm32f7_i2c_wait_free_bus(i2c_dev);
1692         if (ret)
1693                 goto pm_free;
1694
1695         stm32f7_i2c_xfer_msg(i2c_dev, msgs);
1696
1697         time_left = wait_for_completion_timeout(&i2c_dev->complete,
1698                                                 i2c_dev->adap.timeout);
1699         ret = f7_msg->result;
1700         if (ret) {
1701                 if (i2c_dev->use_dma)
1702                         dmaengine_synchronize(dma->chan_using);
1703
1704                 /*
1705                  * It is possible that some unsent data have already been
1706                  * written into TXDR. To avoid sending old data in a
1707                  * further transfer, flush TXDR in case of any error
1708                  */
1709                 writel_relaxed(STM32F7_I2C_ISR_TXE,
1710                                i2c_dev->base + STM32F7_I2C_ISR);
1711                 goto pm_free;
1712         }
1713
1714         if (!time_left) {
1715                 dev_dbg(i2c_dev->dev, "Access to slave 0x%x timed out\n",
1716                         i2c_dev->msg->addr);
1717                 if (i2c_dev->use_dma)
1718                         dmaengine_terminate_sync(dma->chan_using);
1719                 stm32f7_i2c_wait_free_bus(i2c_dev);
1720                 ret = -ETIMEDOUT;
1721         }
1722
1723 pm_free:
1724         pm_runtime_mark_last_busy(i2c_dev->dev);
1725         pm_runtime_put_autosuspend(i2c_dev->dev);
1726
1727         return (ret < 0) ? ret : num;
1728 }
1729
1730 static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
1731                                   unsigned short flags, char read_write,
1732                                   u8 command, int size,
1733                                   union i2c_smbus_data *data)
1734 {
1735         struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adapter);
1736         struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg;
1737         struct stm32_i2c_dma *dma = i2c_dev->dma;
1738         struct device *dev = i2c_dev->dev;
1739         unsigned long timeout;
1740         int i, ret;
1741
1742         f7_msg->addr = addr;
1743         f7_msg->size = size;
1744         f7_msg->read_write = read_write;
1745         f7_msg->smbus = true;
1746
1747         ret = pm_runtime_resume_and_get(dev);
1748         if (ret < 0)
1749                 return ret;
1750
1751         ret = stm32f7_i2c_wait_free_bus(i2c_dev);
1752         if (ret)
1753                 goto pm_free;
1754
1755         ret = stm32f7_i2c_smbus_xfer_msg(i2c_dev, flags, command, data);
1756         if (ret)
1757                 goto pm_free;
1758
1759         timeout = wait_for_completion_timeout(&i2c_dev->complete,
1760                                               i2c_dev->adap.timeout);
1761         ret = f7_msg->result;
1762         if (ret) {
1763                 if (i2c_dev->use_dma)
1764                         dmaengine_synchronize(dma->chan_using);
1765
1766                 /*
1767                  * It is possible that some unsent data have already been
1768                  * written into TXDR. To avoid sending old data in a
1769                  * further transfer, flush TXDR in case of any error
1770                  */
1771                 writel_relaxed(STM32F7_I2C_ISR_TXE,
1772                                i2c_dev->base + STM32F7_I2C_ISR);
1773                 goto pm_free;
1774         }
1775
1776         if (!timeout) {
1777                 dev_dbg(dev, "Access to slave 0x%x timed out\n", f7_msg->addr);
1778                 if (i2c_dev->use_dma)
1779                         dmaengine_terminate_sync(dma->chan_using);
1780                 stm32f7_i2c_wait_free_bus(i2c_dev);
1781                 ret = -ETIMEDOUT;
1782                 goto pm_free;
1783         }
1784
1785         /* Check PEC */
1786         if ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK && read_write) {
1787                 ret = stm32f7_i2c_smbus_check_pec(i2c_dev);
1788                 if (ret)
1789                         goto pm_free;
1790         }
1791
1792         if (read_write && size != I2C_SMBUS_QUICK) {
1793                 switch (size) {
1794                 case I2C_SMBUS_BYTE:
1795                 case I2C_SMBUS_BYTE_DATA:
1796                         data->byte = f7_msg->smbus_buf[0];
1797                 break;
1798                 case I2C_SMBUS_WORD_DATA:
1799                 case I2C_SMBUS_PROC_CALL:
1800                         data->word = f7_msg->smbus_buf[0] |
1801                                 (f7_msg->smbus_buf[1] << 8);
1802                 break;
1803                 case I2C_SMBUS_BLOCK_DATA:
1804                 case I2C_SMBUS_BLOCK_PROC_CALL:
1805                 for (i = 0; i <= f7_msg->smbus_buf[0]; i++)
1806                         data->block[i] = f7_msg->smbus_buf[i];
1807                 break;
1808                 default:
1809                         dev_err(dev, "Unsupported smbus transaction\n");
1810                         ret = -EINVAL;
1811                 }
1812         }
1813
1814 pm_free:
1815         pm_runtime_mark_last_busy(dev);
1816         pm_runtime_put_autosuspend(dev);
1817         return ret;
1818 }
1819
1820 static void stm32f7_i2c_enable_wakeup(struct stm32f7_i2c_dev *i2c_dev,
1821                                       bool enable)
1822 {
1823         void __iomem *base = i2c_dev->base;
1824         u32 mask = STM32F7_I2C_CR1_WUPEN;
1825
1826         if (!i2c_dev->wakeup_src)
1827                 return;
1828
1829         if (enable) {
1830                 device_set_wakeup_enable(i2c_dev->dev, true);
1831                 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1832         } else {
1833                 device_set_wakeup_enable(i2c_dev->dev, false);
1834                 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);
1835         }
1836 }
1837
1838 static int stm32f7_i2c_reg_slave(struct i2c_client *slave)
1839 {
1840         struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter);
1841         void __iomem *base = i2c_dev->base;
1842         struct device *dev = i2c_dev->dev;
1843         u32 oar1, oar2, mask;
1844         int id, ret;
1845
1846         if (slave->flags & I2C_CLIENT_PEC) {
1847                 dev_err(dev, "SMBus PEC not supported in slave mode\n");
1848                 return -EINVAL;
1849         }
1850
1851         if (stm32f7_i2c_is_slave_busy(i2c_dev)) {
1852                 dev_err(dev, "Too much slave registered\n");
1853                 return -EBUSY;
1854         }
1855
1856         ret = stm32f7_i2c_get_free_slave_id(i2c_dev, slave, &id);
1857         if (ret)
1858                 return ret;
1859
1860         ret = pm_runtime_resume_and_get(dev);
1861         if (ret < 0)
1862                 return ret;
1863
1864         if (!stm32f7_i2c_is_slave_registered(i2c_dev))
1865                 stm32f7_i2c_enable_wakeup(i2c_dev, true);
1866
1867         switch (id) {
1868         case 0:
1869                 /* Slave SMBus Host */
1870                 i2c_dev->slave[id] = slave;
1871                 break;
1872
1873         case 1:
1874                 /* Configure Own Address 1 */
1875                 oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
1876                 oar1 &= ~STM32F7_I2C_OAR1_MASK;
1877                 if (slave->flags & I2C_CLIENT_TEN) {
1878                         oar1 |= STM32F7_I2C_OAR1_OA1_10(slave->addr);
1879                         oar1 |= STM32F7_I2C_OAR1_OA1MODE;
1880                 } else {
1881                         oar1 |= STM32F7_I2C_OAR1_OA1_7(slave->addr);
1882                 }
1883                 oar1 |= STM32F7_I2C_OAR1_OA1EN;
1884                 i2c_dev->slave[id] = slave;
1885                 writel_relaxed(oar1, i2c_dev->base + STM32F7_I2C_OAR1);
1886                 break;
1887
1888         case 2:
1889                 /* Configure Own Address 2 */
1890                 oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2);
1891                 oar2 &= ~STM32F7_I2C_OAR2_MASK;
1892                 if (slave->flags & I2C_CLIENT_TEN) {
1893                         ret = -EOPNOTSUPP;
1894                         goto pm_free;
1895                 }
1896
1897                 oar2 |= STM32F7_I2C_OAR2_OA2_7(slave->addr);
1898                 oar2 |= STM32F7_I2C_OAR2_OA2EN;
1899                 i2c_dev->slave[id] = slave;
1900                 writel_relaxed(oar2, i2c_dev->base + STM32F7_I2C_OAR2);
1901                 break;
1902
1903         default:
1904                 dev_err(dev, "I2C slave id not supported\n");
1905                 ret = -ENODEV;
1906                 goto pm_free;
1907         }
1908
1909         /* Enable ACK */
1910         stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, STM32F7_I2C_CR2_NACK);
1911
1912         /* Enable Address match interrupt, error interrupt and enable I2C  */
1913         mask = STM32F7_I2C_CR1_ADDRIE | STM32F7_I2C_CR1_ERRIE |
1914                 STM32F7_I2C_CR1_PE;
1915         stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
1916
1917         ret = 0;
1918 pm_free:
1919         if (!stm32f7_i2c_is_slave_registered(i2c_dev))
1920                 stm32f7_i2c_enable_wakeup(i2c_dev, false);
1921
1922         pm_runtime_mark_last_busy(dev);
1923         pm_runtime_put_autosuspend(dev);
1924
1925         return ret;
1926 }
1927
1928 static int stm32f7_i2c_unreg_slave(struct i2c_client *slave)
1929 {
1930         struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter);
1931         void __iomem *base = i2c_dev->base;
1932         u32 mask;
1933         int id, ret;
1934
1935         ret = stm32f7_i2c_get_slave_id(i2c_dev, slave, &id);
1936         if (ret)
1937                 return ret;
1938
1939         WARN_ON(!i2c_dev->slave[id]);
1940
1941         ret = pm_runtime_resume_and_get(i2c_dev->dev);
1942         if (ret < 0)
1943                 return ret;
1944
1945         if (id == 1) {
1946                 mask = STM32F7_I2C_OAR1_OA1EN;
1947                 stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR1, mask);
1948         } else if (id == 2) {
1949                 mask = STM32F7_I2C_OAR2_OA2EN;
1950                 stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR2, mask);
1951         }
1952
1953         i2c_dev->slave[id] = NULL;
1954
1955         if (!stm32f7_i2c_is_slave_registered(i2c_dev)) {
1956                 stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_ALL_IRQ_MASK);
1957                 stm32f7_i2c_enable_wakeup(i2c_dev, false);
1958         }
1959
1960         pm_runtime_mark_last_busy(i2c_dev->dev);
1961         pm_runtime_put_autosuspend(i2c_dev->dev);
1962
1963         return 0;
1964 }
1965
1966 static int stm32f7_i2c_write_fm_plus_bits(struct stm32f7_i2c_dev *i2c_dev,
1967                                           bool enable)
1968 {
1969         int ret;
1970
1971         if (i2c_dev->bus_rate <= I2C_MAX_FAST_MODE_FREQ ||
1972             IS_ERR_OR_NULL(i2c_dev->regmap))
1973                 /* Optional */
1974                 return 0;
1975
1976         if (i2c_dev->fmp_sreg == i2c_dev->fmp_creg)
1977                 ret = regmap_update_bits(i2c_dev->regmap,
1978                                          i2c_dev->fmp_sreg,
1979                                          i2c_dev->fmp_mask,
1980                                          enable ? i2c_dev->fmp_mask : 0);
1981         else
1982                 ret = regmap_write(i2c_dev->regmap,
1983                                    enable ? i2c_dev->fmp_sreg :
1984                                             i2c_dev->fmp_creg,
1985                                    i2c_dev->fmp_mask);
1986
1987         return ret;
1988 }
1989
1990 static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev,
1991                                           struct stm32f7_i2c_dev *i2c_dev)
1992 {
1993         struct device_node *np = pdev->dev.of_node;
1994         int ret;
1995
1996         i2c_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg-fmp");
1997         if (IS_ERR(i2c_dev->regmap))
1998                 /* Optional */
1999                 return 0;
2000
2001         ret = of_property_read_u32_index(np, "st,syscfg-fmp", 1,
2002                                          &i2c_dev->fmp_sreg);
2003         if (ret)
2004                 return ret;
2005
2006         i2c_dev->fmp_creg = i2c_dev->fmp_sreg +
2007                                i2c_dev->setup.fmp_clr_offset;
2008
2009         return of_property_read_u32_index(np, "st,syscfg-fmp", 2,
2010                                           &i2c_dev->fmp_mask);
2011 }
2012
2013 static int stm32f7_i2c_enable_smbus_host(struct stm32f7_i2c_dev *i2c_dev)
2014 {
2015         struct i2c_adapter *adap = &i2c_dev->adap;
2016         void __iomem *base = i2c_dev->base;
2017         struct i2c_client *client;
2018
2019         client = i2c_new_slave_host_notify_device(adap);
2020         if (IS_ERR(client))
2021                 return PTR_ERR(client);
2022
2023         i2c_dev->host_notify_client = client;
2024
2025         /* Enable SMBus Host address */
2026         stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_SMBHEN);
2027
2028         return 0;
2029 }
2030
2031 static void stm32f7_i2c_disable_smbus_host(struct stm32f7_i2c_dev *i2c_dev)
2032 {
2033         void __iomem *base = i2c_dev->base;
2034
2035         if (i2c_dev->host_notify_client) {
2036                 /* Disable SMBus Host address */
2037                 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1,
2038                                      STM32F7_I2C_CR1_SMBHEN);
2039                 i2c_free_slave_host_notify_device(i2c_dev->host_notify_client);
2040         }
2041 }
2042
2043 static int stm32f7_i2c_enable_smbus_alert(struct stm32f7_i2c_dev *i2c_dev)
2044 {
2045         struct stm32f7_i2c_alert *alert;
2046         struct i2c_adapter *adap = &i2c_dev->adap;
2047         struct device *dev = i2c_dev->dev;
2048         void __iomem *base = i2c_dev->base;
2049
2050         alert = devm_kzalloc(dev, sizeof(*alert), GFP_KERNEL);
2051         if (!alert)
2052                 return -ENOMEM;
2053
2054         alert->ara = i2c_new_smbus_alert_device(adap, &alert->setup);
2055         if (IS_ERR(alert->ara))
2056                 return PTR_ERR(alert->ara);
2057
2058         i2c_dev->alert = alert;
2059
2060         /* Enable SMBus Alert */
2061         stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_ALERTEN);
2062
2063         return 0;
2064 }
2065
2066 static void stm32f7_i2c_disable_smbus_alert(struct stm32f7_i2c_dev *i2c_dev)
2067 {
2068         struct stm32f7_i2c_alert *alert = i2c_dev->alert;
2069         void __iomem *base = i2c_dev->base;
2070
2071         if (alert) {
2072                 /* Disable SMBus Alert */
2073                 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1,
2074                                      STM32F7_I2C_CR1_ALERTEN);
2075                 i2c_unregister_device(alert->ara);
2076         }
2077 }
2078
2079 static u32 stm32f7_i2c_func(struct i2c_adapter *adap)
2080 {
2081         struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
2082
2083         u32 func = I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SLAVE |
2084                    I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
2085                    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
2086                    I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2087                    I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC |
2088                    I2C_FUNC_SMBUS_I2C_BLOCK;
2089
2090         if (i2c_dev->smbus_mode)
2091                 func |= I2C_FUNC_SMBUS_HOST_NOTIFY;
2092
2093         return func;
2094 }
2095
2096 static const struct i2c_algorithm stm32f7_i2c_algo = {
2097         .master_xfer = stm32f7_i2c_xfer,
2098         .smbus_xfer = stm32f7_i2c_smbus_xfer,
2099         .functionality = stm32f7_i2c_func,
2100         .reg_slave = stm32f7_i2c_reg_slave,
2101         .unreg_slave = stm32f7_i2c_unreg_slave,
2102 };
2103
2104 static int stm32f7_i2c_probe(struct platform_device *pdev)
2105 {
2106         struct stm32f7_i2c_dev *i2c_dev;
2107         const struct stm32f7_i2c_setup *setup;
2108         struct resource *res;
2109         struct i2c_adapter *adap;
2110         struct reset_control *rst;
2111         dma_addr_t phy_addr;
2112         int irq_error, irq_event, ret;
2113
2114         i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
2115         if (!i2c_dev)
2116                 return -ENOMEM;
2117
2118         i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
2119         if (IS_ERR(i2c_dev->base))
2120                 return PTR_ERR(i2c_dev->base);
2121         phy_addr = (dma_addr_t)res->start;
2122
2123         irq_event = platform_get_irq(pdev, 0);
2124         if (irq_event <= 0)
2125                 return irq_event ? : -ENOENT;
2126
2127         irq_error = platform_get_irq(pdev, 1);
2128         if (irq_error <= 0)
2129                 return irq_error ? : -ENOENT;
2130
2131         i2c_dev->wakeup_src = of_property_read_bool(pdev->dev.of_node,
2132                                                     "wakeup-source");
2133
2134         i2c_dev->clk = devm_clk_get(&pdev->dev, NULL);
2135         if (IS_ERR(i2c_dev->clk))
2136                 return dev_err_probe(&pdev->dev, PTR_ERR(i2c_dev->clk),
2137                                      "Failed to get controller clock\n");
2138
2139         ret = clk_prepare_enable(i2c_dev->clk);
2140         if (ret) {
2141                 dev_err(&pdev->dev, "Failed to prepare_enable clock\n");
2142                 return ret;
2143         }
2144
2145         rst = devm_reset_control_get(&pdev->dev, NULL);
2146         if (IS_ERR(rst)) {
2147                 ret = dev_err_probe(&pdev->dev, PTR_ERR(rst),
2148                                     "Error: Missing reset ctrl\n");
2149                 goto clk_free;
2150         }
2151         reset_control_assert(rst);
2152         udelay(2);
2153         reset_control_deassert(rst);
2154
2155         i2c_dev->dev = &pdev->dev;
2156
2157         ret = devm_request_threaded_irq(&pdev->dev, irq_event,
2158                                         stm32f7_i2c_isr_event,
2159                                         stm32f7_i2c_isr_event_thread,
2160                                         IRQF_ONESHOT,
2161                                         pdev->name, i2c_dev);
2162         if (ret) {
2163                 dev_err(&pdev->dev, "Failed to request irq event %i\n",
2164                         irq_event);
2165                 goto clk_free;
2166         }
2167
2168         ret = devm_request_irq(&pdev->dev, irq_error, stm32f7_i2c_isr_error, 0,
2169                                pdev->name, i2c_dev);
2170         if (ret) {
2171                 dev_err(&pdev->dev, "Failed to request irq error %i\n",
2172                         irq_error);
2173                 goto clk_free;
2174         }
2175
2176         setup = of_device_get_match_data(&pdev->dev);
2177         if (!setup) {
2178                 dev_err(&pdev->dev, "Can't get device data\n");
2179                 ret = -ENODEV;
2180                 goto clk_free;
2181         }
2182         i2c_dev->setup = *setup;
2183
2184         ret = stm32f7_i2c_setup_timing(i2c_dev, &i2c_dev->setup);
2185         if (ret)
2186                 goto clk_free;
2187
2188         /* Setup Fast mode plus if necessary */
2189         if (i2c_dev->bus_rate > I2C_MAX_FAST_MODE_FREQ) {
2190                 ret = stm32f7_i2c_setup_fm_plus_bits(pdev, i2c_dev);
2191                 if (ret)
2192                         goto clk_free;
2193                 ret = stm32f7_i2c_write_fm_plus_bits(i2c_dev, true);
2194                 if (ret)
2195                         goto clk_free;
2196         }
2197
2198         adap = &i2c_dev->adap;
2199         i2c_set_adapdata(adap, i2c_dev);
2200         snprintf(adap->name, sizeof(adap->name), "STM32F7 I2C(%pa)",
2201                  &res->start);
2202         adap->owner = THIS_MODULE;
2203         adap->timeout = 2 * HZ;
2204         adap->retries = 3;
2205         adap->algo = &stm32f7_i2c_algo;
2206         adap->dev.parent = &pdev->dev;
2207         adap->dev.of_node = pdev->dev.of_node;
2208
2209         init_completion(&i2c_dev->complete);
2210
2211         /* Init DMA config if supported */
2212         i2c_dev->dma = stm32_i2c_dma_request(i2c_dev->dev, phy_addr,
2213                                              STM32F7_I2C_TXDR,
2214                                              STM32F7_I2C_RXDR);
2215         if (IS_ERR(i2c_dev->dma)) {
2216                 ret = PTR_ERR(i2c_dev->dma);
2217                 /* DMA support is optional, only report other errors */
2218                 if (ret != -ENODEV)
2219                         goto fmp_clear;
2220                 dev_dbg(i2c_dev->dev, "No DMA option: fallback using interrupts\n");
2221                 i2c_dev->dma = NULL;
2222         }
2223
2224         if (i2c_dev->wakeup_src) {
2225                 device_set_wakeup_capable(i2c_dev->dev, true);
2226
2227                 ret = dev_pm_set_wake_irq(i2c_dev->dev, irq_event);
2228                 if (ret) {
2229                         dev_err(i2c_dev->dev, "Failed to set wake up irq\n");
2230                         goto clr_wakeup_capable;
2231                 }
2232         }
2233
2234         platform_set_drvdata(pdev, i2c_dev);
2235
2236         pm_runtime_set_autosuspend_delay(i2c_dev->dev,
2237                                          STM32F7_AUTOSUSPEND_DELAY);
2238         pm_runtime_use_autosuspend(i2c_dev->dev);
2239         pm_runtime_set_active(i2c_dev->dev);
2240         pm_runtime_enable(i2c_dev->dev);
2241
2242         pm_runtime_get_noresume(&pdev->dev);
2243
2244         stm32f7_i2c_hw_config(i2c_dev);
2245
2246         i2c_dev->smbus_mode = of_property_read_bool(pdev->dev.of_node, "smbus");
2247
2248         ret = i2c_add_adapter(adap);
2249         if (ret)
2250                 goto pm_disable;
2251
2252         if (i2c_dev->smbus_mode) {
2253                 ret = stm32f7_i2c_enable_smbus_host(i2c_dev);
2254                 if (ret) {
2255                         dev_err(i2c_dev->dev,
2256                                 "failed to enable SMBus Host-Notify protocol (%d)\n",
2257                                 ret);
2258                         goto i2c_adapter_remove;
2259                 }
2260         }
2261
2262         if (of_property_read_bool(pdev->dev.of_node, "smbus-alert")) {
2263                 ret = stm32f7_i2c_enable_smbus_alert(i2c_dev);
2264                 if (ret) {
2265                         dev_err(i2c_dev->dev,
2266                                 "failed to enable SMBus alert protocol (%d)\n",
2267                                 ret);
2268                         goto i2c_disable_smbus_host;
2269                 }
2270         }
2271
2272         dev_info(i2c_dev->dev, "STM32F7 I2C-%d bus adapter\n", adap->nr);
2273
2274         pm_runtime_mark_last_busy(i2c_dev->dev);
2275         pm_runtime_put_autosuspend(i2c_dev->dev);
2276
2277         return 0;
2278
2279 i2c_disable_smbus_host:
2280         stm32f7_i2c_disable_smbus_host(i2c_dev);
2281
2282 i2c_adapter_remove:
2283         i2c_del_adapter(adap);
2284
2285 pm_disable:
2286         pm_runtime_put_noidle(i2c_dev->dev);
2287         pm_runtime_disable(i2c_dev->dev);
2288         pm_runtime_set_suspended(i2c_dev->dev);
2289         pm_runtime_dont_use_autosuspend(i2c_dev->dev);
2290
2291         if (i2c_dev->wakeup_src)
2292                 dev_pm_clear_wake_irq(i2c_dev->dev);
2293
2294 clr_wakeup_capable:
2295         if (i2c_dev->wakeup_src)
2296                 device_set_wakeup_capable(i2c_dev->dev, false);
2297
2298         if (i2c_dev->dma) {
2299                 stm32_i2c_dma_free(i2c_dev->dma);
2300                 i2c_dev->dma = NULL;
2301         }
2302
2303 fmp_clear:
2304         stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
2305
2306 clk_free:
2307         clk_disable_unprepare(i2c_dev->clk);
2308
2309         return ret;
2310 }
2311
2312 static void stm32f7_i2c_remove(struct platform_device *pdev)
2313 {
2314         struct stm32f7_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
2315
2316         stm32f7_i2c_disable_smbus_alert(i2c_dev);
2317         stm32f7_i2c_disable_smbus_host(i2c_dev);
2318
2319         i2c_del_adapter(&i2c_dev->adap);
2320         pm_runtime_get_sync(i2c_dev->dev);
2321
2322         if (i2c_dev->wakeup_src) {
2323                 dev_pm_clear_wake_irq(i2c_dev->dev);
2324                 /*
2325                  * enforce that wakeup is disabled and that the device
2326                  * is marked as non wakeup capable
2327                  */
2328                 device_init_wakeup(i2c_dev->dev, false);
2329         }
2330
2331         pm_runtime_put_noidle(i2c_dev->dev);
2332         pm_runtime_disable(i2c_dev->dev);
2333         pm_runtime_set_suspended(i2c_dev->dev);
2334         pm_runtime_dont_use_autosuspend(i2c_dev->dev);
2335
2336         if (i2c_dev->dma) {
2337                 stm32_i2c_dma_free(i2c_dev->dma);
2338                 i2c_dev->dma = NULL;
2339         }
2340
2341         stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
2342
2343         clk_disable_unprepare(i2c_dev->clk);
2344 }
2345
2346 static int __maybe_unused stm32f7_i2c_runtime_suspend(struct device *dev)
2347 {
2348         struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2349
2350         if (!stm32f7_i2c_is_slave_registered(i2c_dev))
2351                 clk_disable_unprepare(i2c_dev->clk);
2352
2353         return 0;
2354 }
2355
2356 static int __maybe_unused stm32f7_i2c_runtime_resume(struct device *dev)
2357 {
2358         struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2359         int ret;
2360
2361         if (!stm32f7_i2c_is_slave_registered(i2c_dev)) {
2362                 ret = clk_prepare_enable(i2c_dev->clk);
2363                 if (ret) {
2364                         dev_err(dev, "failed to prepare_enable clock\n");
2365                         return ret;
2366                 }
2367         }
2368
2369         return 0;
2370 }
2371
2372 static int __maybe_unused stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev)
2373 {
2374         int ret;
2375         struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
2376
2377         ret = pm_runtime_resume_and_get(i2c_dev->dev);
2378         if (ret < 0)
2379                 return ret;
2380
2381         backup_regs->cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1);
2382         backup_regs->cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
2383         backup_regs->oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
2384         backup_regs->oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2);
2385         backup_regs->tmgr = readl_relaxed(i2c_dev->base + STM32F7_I2C_TIMINGR);
2386         stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
2387
2388         pm_runtime_put_sync(i2c_dev->dev);
2389
2390         return ret;
2391 }
2392
2393 static int __maybe_unused stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev)
2394 {
2395         u32 cr1;
2396         int ret;
2397         struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
2398
2399         ret = pm_runtime_resume_and_get(i2c_dev->dev);
2400         if (ret < 0)
2401                 return ret;
2402
2403         cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1);
2404         if (cr1 & STM32F7_I2C_CR1_PE)
2405                 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
2406                                      STM32F7_I2C_CR1_PE);
2407
2408         writel_relaxed(backup_regs->tmgr, i2c_dev->base + STM32F7_I2C_TIMINGR);
2409         writel_relaxed(backup_regs->cr1 & ~STM32F7_I2C_CR1_PE,
2410                        i2c_dev->base + STM32F7_I2C_CR1);
2411         if (backup_regs->cr1 & STM32F7_I2C_CR1_PE)
2412                 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
2413                                      STM32F7_I2C_CR1_PE);
2414         writel_relaxed(backup_regs->cr2, i2c_dev->base + STM32F7_I2C_CR2);
2415         writel_relaxed(backup_regs->oar1, i2c_dev->base + STM32F7_I2C_OAR1);
2416         writel_relaxed(backup_regs->oar2, i2c_dev->base + STM32F7_I2C_OAR2);
2417         stm32f7_i2c_write_fm_plus_bits(i2c_dev, true);
2418
2419         pm_runtime_put_sync(i2c_dev->dev);
2420
2421         return ret;
2422 }
2423
2424 static int __maybe_unused stm32f7_i2c_suspend(struct device *dev)
2425 {
2426         struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2427         int ret;
2428
2429         i2c_mark_adapter_suspended(&i2c_dev->adap);
2430
2431         if (!device_may_wakeup(dev) && !device_wakeup_path(dev)) {
2432                 ret = stm32f7_i2c_regs_backup(i2c_dev);
2433                 if (ret < 0) {
2434                         i2c_mark_adapter_resumed(&i2c_dev->adap);
2435                         return ret;
2436                 }
2437
2438                 pinctrl_pm_select_sleep_state(dev);
2439                 pm_runtime_force_suspend(dev);
2440         }
2441
2442         return 0;
2443 }
2444
2445 static int __maybe_unused stm32f7_i2c_resume(struct device *dev)
2446 {
2447         struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
2448         int ret;
2449
2450         if (!device_may_wakeup(dev) && !device_wakeup_path(dev)) {
2451                 ret = pm_runtime_force_resume(dev);
2452                 if (ret < 0)
2453                         return ret;
2454                 pinctrl_pm_select_default_state(dev);
2455
2456                 ret = stm32f7_i2c_regs_restore(i2c_dev);
2457                 if (ret < 0)
2458                         return ret;
2459         }
2460
2461         i2c_mark_adapter_resumed(&i2c_dev->adap);
2462
2463         return 0;
2464 }
2465
2466 static const struct dev_pm_ops stm32f7_i2c_pm_ops = {
2467         SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend,
2468                            stm32f7_i2c_runtime_resume, NULL)
2469         SET_SYSTEM_SLEEP_PM_OPS(stm32f7_i2c_suspend, stm32f7_i2c_resume)
2470 };
2471
2472 static const struct of_device_id stm32f7_i2c_match[] = {
2473         { .compatible = "st,stm32f7-i2c", .data = &stm32f7_setup},
2474         { .compatible = "st,stm32mp15-i2c", .data = &stm32mp15_setup},
2475         { .compatible = "st,stm32mp13-i2c", .data = &stm32mp13_setup},
2476         {},
2477 };
2478 MODULE_DEVICE_TABLE(of, stm32f7_i2c_match);
2479
2480 static struct platform_driver stm32f7_i2c_driver = {
2481         .driver = {
2482                 .name = "stm32f7-i2c",
2483                 .of_match_table = stm32f7_i2c_match,
2484                 .pm = &stm32f7_i2c_pm_ops,
2485         },
2486         .probe = stm32f7_i2c_probe,
2487         .remove_new = stm32f7_i2c_remove,
2488 };
2489
2490 module_platform_driver(stm32f7_i2c_driver);
2491
2492 MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>");
2493 MODULE_DESCRIPTION("STMicroelectronics STM32F7 I2C driver");
2494 MODULE_LICENSE("GPL v2");