drivers/i2c/ihs_i2c.c

   1 /*
   2  * (C) Copyright 2013
   3  * Dirk Eibach,  Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <i2c.h>
  10 #ifdef CONFIG_DM_I2C
  11 #include <dm.h>
  12 #include <fpgamap.h>
  13 #include "../misc/gdsys_soc.h"
  14 #else
  15 #include <gdsys_fpga.h>
  16 #endif
  17 #include <asm/unaligned.h>
  18
  19 #ifdef CONFIG_DM_I2C
  20 struct ihs_i2c_priv {
  21         uint speed;
  22         phys_addr_t addr;
  23 };
  24
  25 enum {
  26         REG_INTERRUPT_STATUS = 0x00,
  27         REG_INTERRUPT_ENABLE_CONTROL = 0x02,
  28         REG_WRITE_MAILBOX_EXT = 0x04,
  29         REG_WRITE_MAILBOX = 0x06,
  30         REG_READ_MAILBOX_EXT = 0x08,
  31         REG_READ_MAILBOX = 0x0A,
  32 };
  33
  34 #else /* !CONFIG_DM_I2C */
  35 DECLARE_GLOBAL_DATA_PTR;
  36
  37 #ifdef CONFIG_SYS_I2C_IHS_DUAL
  38
  39 #define I2C_SET_REG(fld, val) \
  40         do { \
  41                 if (I2C_ADAP_HWNR & 0x10) \
  42                         FPGA_SET_REG(I2C_ADAP_HWNR & 0xf, i2c1.fld, val); \
  43                 else \
  44                         FPGA_SET_REG(I2C_ADAP_HWNR, i2c0.fld, val); \
  45         } while (0)
  46 #else
  47 #define I2C_SET_REG(fld, val) \
  48                 FPGA_SET_REG(I2C_ADAP_HWNR, i2c0.fld, val)
  49 #endif
  50
  51 #ifdef CONFIG_SYS_I2C_IHS_DUAL
  52 #define I2C_GET_REG(fld, val) \
  53         do {                                    \
  54                 if (I2C_ADAP_HWNR & 0x10) \
  55                         FPGA_GET_REG(I2C_ADAP_HWNR & 0xf, i2c1.fld, val); \
  56                 else \
  57                         FPGA_GET_REG(I2C_ADAP_HWNR, i2c0.fld, val); \
  58         } while (0)
  59 #else
  60 #define I2C_GET_REG(fld, val) \
  61                 FPGA_GET_REG(I2C_ADAP_HWNR, i2c0.fld, val)
  62 #endif
  63 #endif /* CONFIG_DM_I2C */
  64
  65 enum {
  66         I2CINT_ERROR_EV = BIT(13),
  67         I2CINT_TRANSMIT_EV = BIT(14),
  68         I2CINT_RECEIVE_EV = BIT(15),
  69 };
  70
  71 enum {
  72         I2CMB_READ = 0 << 10,
  73         I2CMB_WRITE = 1 << 10,
  74         I2CMB_1BYTE = 0 << 11,
  75         I2CMB_2BYTE = 1 << 11,
  76         I2CMB_DONT_HOLD_BUS = 0 << 13,
  77         I2CMB_HOLD_BUS = 1 << 13,
  78         I2CMB_NATIVE = 2 << 14,
  79 };
  80
  81 enum {
  82         I2COP_WRITE = 0,
  83         I2COP_READ = 1,
  84 };
  85
  86 #ifdef CONFIG_DM_I2C
  87 static int wait_for_int(struct udevice *dev, int read)
  88 #else
  89 static int wait_for_int(bool read)
  90 #endif
  91 {
  92         u16 val;
  93         uint ctr = 0;
  94 #ifdef CONFIG_DM_I2C
  95         struct ihs_i2c_priv *priv = dev_get_priv(dev);
  96         struct udevice *fpga;
  97
  98         gdsys_soc_get_fpga(dev, &fpga);
  99 #endif
 100
 101 #ifdef CONFIG_DM_I2C
 102         fpgamap_read16(fpga, priv->addr + REG_INTERRUPT_STATUS, &val);
 103 #else
 104         I2C_GET_REG(interrupt_status, &val);
 105 #endif
 106         /* Wait until error or receive/transmit interrupt was raised */
 107         while (!(val & (I2CINT_ERROR_EV
 108                | (read ? I2CINT_RECEIVE_EV : I2CINT_TRANSMIT_EV)))) {
 109                 udelay(10);
 110                 if (ctr++ > 5000)
 111                         return 1;
 112 #ifdef CONFIG_DM_I2C
 113                 fpgamap_read16(fpga, priv->addr + REG_INTERRUPT_STATUS, &val);
 114 #else
 115                 I2C_GET_REG(interrupt_status, &val);
 116 #endif
 117         }
 118
 119         return (val & I2CINT_ERROR_EV) ? 1 : 0;
 120 }
 121
 122 #ifdef CONFIG_DM_I2C
 123 static int ihs_i2c_transfer(struct udevice *dev, uchar chip,
 124                             uchar *buffer, int len, int read, bool is_last)
 125 #else
 126 static int ihs_i2c_transfer(uchar chip, uchar *buffer, int len, bool read,
 127                             bool is_last)
 128 #endif
 129 {
 130         u16 val;
 131 #ifdef CONFIG_DM_I2C
 132         struct ihs_i2c_priv *priv = dev_get_priv(dev);
 133         struct udevice *fpga;
 134
 135         gdsys_soc_get_fpga(dev, &fpga);
 136 #endif
 137
 138         /* Clear interrupt status */
 139 #ifdef CONFIG_DM_I2C
 140         fpgamap_write16(fpga, priv->addr + REG_INTERRUPT_STATUS,
 141                         I2CINT_ERROR_EV | I2CINT_RECEIVE_EV | I2CINT_TRANSMIT_EV);
 142         fpgamap_read16(fpga, priv->addr + REG_INTERRUPT_STATUS, &val);
 143 #else
 144         I2C_SET_REG(interrupt_status, I2CINT_ERROR_EV
 145                      | I2CINT_RECEIVE_EV | I2CINT_TRANSMIT_EV);
 146         I2C_GET_REG(interrupt_status, &val);
 147 #endif
 148
 149         /* If we want to write and have data, write the bytes to the mailbox */
 150         if (!read && len) {
 151                 val = buffer[0];
 152
 153                 if (len > 1)
 154                         val |= buffer[1] << 8;
 155 #ifdef CONFIG_DM_I2C
 156                 fpgamap_write16(fpga, priv->addr + REG_WRITE_MAILBOX_EXT, val);
 157 #else
 158                 I2C_SET_REG(write_mailbox_ext, val);
 159 #endif
 160         }
 161
 162 #ifdef CONFIG_DM_I2C
 163         fpgamap_write16(fpga, priv->addr + REG_WRITE_MAILBOX,
 164                         I2CMB_NATIVE
 165                         | (read ? I2CMB_READ : I2CMB_WRITE)
 166                         | (chip << 1)
 167                         | ((len > 1) ? I2CMB_2BYTE : I2CMB_1BYTE)
 168                         | (!is_last ? I2CMB_HOLD_BUS : I2CMB_DONT_HOLD_BUS));
 169 #else
 170         I2C_SET_REG(write_mailbox,
 171                     I2CMB_NATIVE
 172                     | (read ? 0 : I2CMB_WRITE)
 173                     | (chip << 1)
 174                     | ((len > 1) ? I2CMB_2BYTE : 0)
 175                     | (is_last ? 0 : I2CMB_HOLD_BUS));
 176 #endif
 177
 178 #ifdef CONFIG_DM_I2C
 179         if (wait_for_int(dev, read))
 180 #else
 181         if (wait_for_int(read))
 182 #endif
 183                 return 1;
 184
 185         /* If we want to read, get the bytes from the mailbox */
 186         if (read) {
 187 #ifdef CONFIG_DM_I2C
 188                 fpgamap_read16(fpga, priv->addr + REG_READ_MAILBOX_EXT, &val);
 189 #else
 190                 I2C_GET_REG(read_mailbox_ext, &val);
 191 #endif
 192                 buffer[0] = val & 0xff;
 193                 if (len > 1)
 194                         buffer[1] = val >> 8;
 195         }
 196
 197         return 0;
 198 }
 199
 200 #ifdef CONFIG_DM_I2C
 201 static int ihs_i2c_send_buffer(struct udevice *dev, uchar chip, u8 *data, int len, bool hold_bus, int read)
 202 #else
 203 static int ihs_i2c_send_buffer(uchar chip, u8 *data, int len, bool hold_bus,
 204                                int read)
 205 #endif
 206 {
 207         while (len) {
 208                 int transfer = min(len, 2);
 209                 bool is_last = len <= transfer;
 210
 211 #ifdef CONFIG_DM_I2C
 212                 if (ihs_i2c_transfer(dev, chip, data, transfer, read,
 213                                      hold_bus ? false : is_last))
 214                         return 1;
 215 #else
 216                 if (ihs_i2c_transfer(chip, data, transfer, read,
 217                                      hold_bus ? false : is_last))
 218                         return 1;
 219 #endif
 220
 221                 data += transfer;
 222                 len -= transfer;
 223         }
 224
 225         return 0;
 226 }
 227
 228 #ifdef CONFIG_DM_I2C
 229 static int ihs_i2c_address(struct udevice *dev, uchar chip, u8 *addr, int alen,
 230                            bool hold_bus)
 231 #else
 232 static int ihs_i2c_address(uchar chip, u8 *addr, int alen, bool hold_bus)
 233 #endif
 234 {
 235 #ifdef CONFIG_DM_I2C
 236         return ihs_i2c_send_buffer(dev, chip, addr, alen, hold_bus, I2COP_WRITE);
 237 #else
 238         return ihs_i2c_send_buffer(chip, addr, alen, hold_bus, I2COP_WRITE);
 239 #endif
 240 }
 241
 242 #ifdef CONFIG_DM_I2C
 243 static int ihs_i2c_access(struct udevice *dev, uchar chip, u8 *addr,
 244                           int alen, uchar *buffer, int len, int read)
 245 #else
 246 static int ihs_i2c_access(struct i2c_adapter *adap, uchar chip, u8 *addr,
 247                           int alen, uchar *buffer, int len, int read)
 248 #endif
 249 {
 250         /* Don't hold the bus if length of data to send/receive is zero */
 251 #ifdef CONFIG_DM_I2C
 252         if (len <= 0 || ihs_i2c_address(dev, chip, addr, alen, len))
 253                 return 1;
 254 #else
 255         if (len <= 0 || ihs_i2c_address(chip, addr, alen, len))
 256                 return 1;
 257 #endif
 258
 259 #ifdef CONFIG_DM_I2C
 260         return ihs_i2c_send_buffer(dev, chip, buffer, len, false, read);
 261 #else
 262         return ihs_i2c_send_buffer(chip, buffer, len, false, read);
 263 #endif
 264 }
 265
 266 #ifdef CONFIG_DM_I2C
 267
 268 int ihs_i2c_probe(struct udevice *bus)
 269 {
 270         struct ihs_i2c_priv *priv = dev_get_priv(bus);
 271         int addr;
 272
 273         addr = dev_read_u32_default(bus, "reg", -1);
 274
 275         priv->addr = addr;
 276
 277         return 0;
 278 }
 279
 280 static int ihs_i2c_set_bus_speed(struct udevice *bus, uint speed)
 281 {
 282         struct ihs_i2c_priv *priv = dev_get_priv(bus);
 283
 284         if (speed != priv->speed && priv->speed != 0)
 285                 return 1;
 286
 287         priv->speed = speed;
 288
 289         return 0;
 290 }
 291
 292 static int ihs_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
 293 {
 294         struct i2c_msg *dmsg, *omsg, dummy;
 295
 296         memset(&dummy, 0, sizeof(struct i2c_msg));
 297
 298         /* We expect either two messages (one with an offset and one with the
 299          * actucal data) or one message (just data)
 300          */
 301         if (nmsgs > 2 || nmsgs == 0) {
 302                 debug("%s: Only one or two messages are supported.", __func__);
 303                 return -1;
 304         }
 305
 306         omsg = nmsgs == 1 ? &dummy : msg;
 307         dmsg = nmsgs == 1 ? msg : msg + 1;
 308
 309         if (dmsg->flags & I2C_M_RD)
 310                 return ihs_i2c_access(bus, dmsg->addr, omsg->buf,
 311                                       omsg->len, dmsg->buf, dmsg->len,
 312                                       I2COP_READ);
 313         else
 314                 return ihs_i2c_access(bus, dmsg->addr, omsg->buf,
 315                                       omsg->len, dmsg->buf, dmsg->len,
 316                                       I2COP_WRITE);
 317 }
 318
 319 static int ihs_i2c_probe_chip(struct udevice *bus, u32 chip_addr,
 320                               u32 chip_flags)
 321 {
 322         uchar buffer[2];
 323
 324         if (ihs_i2c_transfer(bus, chip_addr, buffer, 0, I2COP_READ, true))
 325                 return 1;
 326
 327         return 0;
 328 }
 329
 330 static const struct dm_i2c_ops ihs_i2c_ops = {
 331         .xfer           = ihs_i2c_xfer,
 332         .probe_chip     = ihs_i2c_probe_chip,
 333         .set_bus_speed  = ihs_i2c_set_bus_speed,
 334 };
 335
 336 static const struct udevice_id ihs_i2c_ids[] = {
 337         { .compatible = "gdsys,ihs_i2cmaster", },
 338         { /* sentinel */ }
 339 };
 340
 341 U_BOOT_DRIVER(i2c_ihs) = {
 342         .name = "i2c_ihs",
 343         .id = UCLASS_I2C,
 344         .of_match = ihs_i2c_ids,
 345         .probe = ihs_i2c_probe,
 346         .priv_auto_alloc_size = sizeof(struct ihs_i2c_priv),
 347         .ops = &ihs_i2c_ops,
 348 };
 349
 350 #else /* CONFIG_DM_I2C */
 351
 352 static void ihs_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
 353 {
 354 #ifdef CONFIG_SYS_I2C_INIT_BOARD
 355         /*
 356          * Call board specific i2c bus reset routine before accessing the
 357          * environment, which might be in a chip on that bus. For details
 358          * about this problem see doc/I2C_Edge_Conditions.
 359          */
 360         i2c_init_board();
 361 #endif
 362 }
 363
 364 static int ihs_i2c_probe(struct i2c_adapter *adap, uchar chip)
 365 {
 366         uchar buffer[2];
 367
 368         if (ihs_i2c_transfer(chip, buffer, 0, I2COP_READ, true))
 369                 return 1;
 370
 371         return 0;
 372 }
 373
 374 static int ihs_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
 375                         int alen, uchar *buffer, int len)
 376 {
 377         u8 addr_bytes[4];
 378
 379         put_unaligned_le32(addr, addr_bytes);
 380
 381         return ihs_i2c_access(adap, chip, addr_bytes, alen, buffer, len,
 382                               I2COP_READ);
 383 }
 384
 385 static int ihs_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
 386                          int alen, uchar *buffer, int len)
 387 {
 388         u8 addr_bytes[4];
 389
 390         put_unaligned_le32(addr, addr_bytes);
 391
 392         return ihs_i2c_access(adap, chip, addr_bytes, alen, buffer, len,
 393                               I2COP_WRITE);
 394 }
 395
 396 static unsigned int ihs_i2c_set_bus_speed(struct i2c_adapter *adap,
 397                                           unsigned int speed)
 398 {
 399         if (speed != adap->speed)
 400                 return 1;
 401         return speed;
 402 }
 403
 404 /*
 405  * Register IHS i2c adapters
 406  */
 407 #ifdef CONFIG_SYS_I2C_IHS_CH0
 408 U_BOOT_I2C_ADAP_COMPLETE(ihs0, ihs_i2c_init, ihs_i2c_probe,
 409                          ihs_i2c_read, ihs_i2c_write,
 410                          ihs_i2c_set_bus_speed,
 411                          CONFIG_SYS_I2C_IHS_SPEED_0,
 412                          CONFIG_SYS_I2C_IHS_SLAVE_0, 0)
 413 #ifdef CONFIG_SYS_I2C_IHS_DUAL
 414 U_BOOT_I2C_ADAP_COMPLETE(ihs0_1, ihs_i2c_init, ihs_i2c_probe,
 415                          ihs_i2c_read, ihs_i2c_write,
 416                          ihs_i2c_set_bus_speed,
 417                          CONFIG_SYS_I2C_IHS_SPEED_0_1,
 418                          CONFIG_SYS_I2C_IHS_SLAVE_0_1, 16)
 419 #endif
 420 #endif
 421 #ifdef CONFIG_SYS_I2C_IHS_CH1
 422 U_BOOT_I2C_ADAP_COMPLETE(ihs1, ihs_i2c_init, ihs_i2c_probe,
 423                          ihs_i2c_read, ihs_i2c_write,
 424                          ihs_i2c_set_bus_speed,
 425                          CONFIG_SYS_I2C_IHS_SPEED_1,
 426                          CONFIG_SYS_I2C_IHS_SLAVE_1, 1)
 427 #ifdef CONFIG_SYS_I2C_IHS_DUAL
 428 U_BOOT_I2C_ADAP_COMPLETE(ihs1_1, ihs_i2c_init, ihs_i2c_probe,
 429                          ihs_i2c_read, ihs_i2c_write,
 430                          ihs_i2c_set_bus_speed,
 431                          CONFIG_SYS_I2C_IHS_SPEED_1_1,
 432                          CONFIG_SYS_I2C_IHS_SLAVE_1_1, 17)
 433 #endif
 434 #endif
 435 #ifdef CONFIG_SYS_I2C_IHS_CH2
 436 U_BOOT_I2C_ADAP_COMPLETE(ihs2, ihs_i2c_init, ihs_i2c_probe,
 437                          ihs_i2c_read, ihs_i2c_write,
 438                          ihs_i2c_set_bus_speed,
 439                          CONFIG_SYS_I2C_IHS_SPEED_2,
 440                          CONFIG_SYS_I2C_IHS_SLAVE_2, 2)
 441 #ifdef CONFIG_SYS_I2C_IHS_DUAL
 442 U_BOOT_I2C_ADAP_COMPLETE(ihs2_1, ihs_i2c_init, ihs_i2c_probe,
 443                          ihs_i2c_read, ihs_i2c_write,
 444                          ihs_i2c_set_bus_speed,
 445                          CONFIG_SYS_I2C_IHS_SPEED_2_1,
 446                          CONFIG_SYS_I2C_IHS_SLAVE_2_1, 18)
 447 #endif
 448 #endif
 449 #ifdef CONFIG_SYS_I2C_IHS_CH3
 450 U_BOOT_I2C_ADAP_COMPLETE(ihs3, ihs_i2c_init, ihs_i2c_probe,
 451                          ihs_i2c_read, ihs_i2c_write,
 452                          ihs_i2c_set_bus_speed,
 453                          CONFIG_SYS_I2C_IHS_SPEED_3,
 454                          CONFIG_SYS_I2C_IHS_SLAVE_3, 3)
 455 #ifdef CONFIG_SYS_I2C_IHS_DUAL
 456 U_BOOT_I2C_ADAP_COMPLETE(ihs3_1, ihs_i2c_init, ihs_i2c_probe,
 457                          ihs_i2c_read, ihs_i2c_write,
 458                          ihs_i2c_set_bus_speed,
 459                          CONFIG_SYS_I2C_IHS_SPEED_3_1,
 460                          CONFIG_SYS_I2C_IHS_SLAVE_3_1, 19)
 461 #endif
 462 #endif
 463 #endif /* CONFIG_DM_I2C */