1 // SPDX-License-Identifier: GPL-2.0+
4 * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
14 #include "designware_i2c.h"
16 struct dw_scl_sda_cfg {
25 /* BayTrail HCNT/LCNT/SDA hold time */
26 static struct dw_scl_sda_cfg byt_config = {
36 struct i2c_regs *regs;
37 struct dw_scl_sda_cfg *scl_sda_cfg;
38 struct reset_ctl_bulk resets;
39 #if CONFIG_IS_ENABLED(CLK)
44 #ifdef CONFIG_SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED
45 static int dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
47 u32 ena = enable ? IC_ENABLE_0B : 0;
49 writel(ena, &i2c_base->ic_enable);
54 static int dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
56 u32 ena = enable ? IC_ENABLE_0B : 0;
60 writel(ena, &i2c_base->ic_enable);
61 if ((readl(&i2c_base->ic_enable_status) & IC_ENABLE_0B) == ena)
65 * Wait 10 times the signaling period of the highest I2C
66 * transfer supported by the driver (for 400KHz this is
67 * 25us) as described in the DesignWare I2C databook.
71 printf("timeout in %sabling I2C adapter\n", enable ? "en" : "dis");
78 * i2c_set_bus_speed - Set the i2c speed
79 * @speed: required i2c speed
83 static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base,
84 struct dw_scl_sda_cfg *scl_sda_cfg,
89 unsigned int hcnt, lcnt;
93 if (speed >= I2C_MAX_SPEED)
94 i2c_spd = IC_SPEED_MODE_MAX;
95 else if (speed >= I2C_FAST_SPEED)
96 i2c_spd = IC_SPEED_MODE_FAST;
98 i2c_spd = IC_SPEED_MODE_STANDARD;
100 /* Get enable setting for restore later */
101 ena = readl(&i2c_base->ic_enable) & IC_ENABLE_0B;
103 /* to set speed cltr must be disabled */
104 dw_i2c_enable(i2c_base, false);
106 cntl = (readl(&i2c_base->ic_con) & (~IC_CON_SPD_MSK));
109 #ifndef CONFIG_X86 /* No High-speed for BayTrail yet */
110 case IC_SPEED_MODE_MAX:
111 cntl |= IC_CON_SPD_SS;
113 hcnt = scl_sda_cfg->fs_hcnt;
114 lcnt = scl_sda_cfg->fs_lcnt;
116 hcnt = (bus_mhz * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO;
117 lcnt = (bus_mhz * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO;
119 writel(hcnt, &i2c_base->ic_hs_scl_hcnt);
120 writel(lcnt, &i2c_base->ic_hs_scl_lcnt);
124 case IC_SPEED_MODE_STANDARD:
125 cntl |= IC_CON_SPD_SS;
127 hcnt = scl_sda_cfg->ss_hcnt;
128 lcnt = scl_sda_cfg->ss_lcnt;
130 hcnt = (bus_mhz * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO;
131 lcnt = (bus_mhz * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO;
133 writel(hcnt, &i2c_base->ic_ss_scl_hcnt);
134 writel(lcnt, &i2c_base->ic_ss_scl_lcnt);
137 case IC_SPEED_MODE_FAST:
139 cntl |= IC_CON_SPD_FS;
141 hcnt = scl_sda_cfg->fs_hcnt;
142 lcnt = scl_sda_cfg->fs_lcnt;
144 hcnt = (bus_mhz * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO;
145 lcnt = (bus_mhz * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO;
147 writel(hcnt, &i2c_base->ic_fs_scl_hcnt);
148 writel(lcnt, &i2c_base->ic_fs_scl_lcnt);
152 writel(cntl, &i2c_base->ic_con);
154 /* Configure SDA Hold Time if required */
156 writel(scl_sda_cfg->sda_hold, &i2c_base->ic_sda_hold);
158 /* Restore back i2c now speed set */
159 if (ena == IC_ENABLE_0B)
160 dw_i2c_enable(i2c_base, true);
166 * i2c_setaddress - Sets the target slave address
167 * @i2c_addr: target i2c address
169 * Sets the target slave address.
171 static void i2c_setaddress(struct i2c_regs *i2c_base, unsigned int i2c_addr)
174 dw_i2c_enable(i2c_base, false);
176 writel(i2c_addr, &i2c_base->ic_tar);
179 dw_i2c_enable(i2c_base, true);
183 * i2c_flush_rxfifo - Flushes the i2c RX FIFO
185 * Flushes the i2c RX FIFO
187 static void i2c_flush_rxfifo(struct i2c_regs *i2c_base)
189 while (readl(&i2c_base->ic_status) & IC_STATUS_RFNE)
190 readl(&i2c_base->ic_cmd_data);
194 * i2c_wait_for_bb - Waits for bus busy
198 static int i2c_wait_for_bb(struct i2c_regs *i2c_base)
200 unsigned long start_time_bb = get_timer(0);
202 while ((readl(&i2c_base->ic_status) & IC_STATUS_MA) ||
203 !(readl(&i2c_base->ic_status) & IC_STATUS_TFE)) {
205 /* Evaluate timeout */
206 if (get_timer(start_time_bb) > (unsigned long)(I2C_BYTE_TO_BB))
213 static int i2c_xfer_init(struct i2c_regs *i2c_base, uchar chip, uint addr,
216 if (i2c_wait_for_bb(i2c_base))
219 i2c_setaddress(i2c_base, chip);
222 /* high byte address going out first */
223 writel((addr >> (alen * 8)) & 0xff,
224 &i2c_base->ic_cmd_data);
229 static int i2c_xfer_finish(struct i2c_regs *i2c_base)
231 ulong start_stop_det = get_timer(0);
234 if ((readl(&i2c_base->ic_raw_intr_stat) & IC_STOP_DET)) {
235 readl(&i2c_base->ic_clr_stop_det);
237 } else if (get_timer(start_stop_det) > I2C_STOPDET_TO) {
242 if (i2c_wait_for_bb(i2c_base)) {
243 printf("Timed out waiting for bus\n");
247 i2c_flush_rxfifo(i2c_base);
253 * i2c_read - Read from i2c memory
254 * @chip: target i2c address
255 * @addr: address to read from
257 * @buffer: buffer for read data
258 * @len: no of bytes to be read
260 * Read from i2c memory.
262 static int __dw_i2c_read(struct i2c_regs *i2c_base, u8 dev, uint addr,
263 int alen, u8 *buffer, int len)
265 unsigned long start_time_rx;
266 unsigned int active = 0;
268 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
270 * EEPROM chips that implement "address overflow" are ones
271 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
272 * address and the extra bits end up in the "chip address"
273 * bit slots. This makes a 24WC08 (1Kbyte) chip look like
274 * four 256 byte chips.
276 * Note that we consider the length of the address field to
277 * still be one byte because the extra address bits are
278 * hidden in the chip address.
280 dev |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
281 addr &= ~(CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW << (alen * 8));
283 debug("%s: fix addr_overflow: dev %02x addr %02x\n", __func__, dev,
287 if (i2c_xfer_init(i2c_base, dev, addr, alen))
290 start_time_rx = get_timer(0);
294 * Avoid writing to ic_cmd_data multiple times
295 * in case this loop spins too quickly and the
296 * ic_status RFNE bit isn't set after the first
297 * write. Subsequent writes to ic_cmd_data can
298 * trigger spurious i2c transfer.
301 writel(IC_CMD | IC_STOP, &i2c_base->ic_cmd_data);
303 writel(IC_CMD, &i2c_base->ic_cmd_data);
307 if (readl(&i2c_base->ic_status) & IC_STATUS_RFNE) {
308 *buffer++ = (uchar)readl(&i2c_base->ic_cmd_data);
310 start_time_rx = get_timer(0);
312 } else if (get_timer(start_time_rx) > I2C_BYTE_TO) {
317 return i2c_xfer_finish(i2c_base);
321 * i2c_write - Write to i2c memory
322 * @chip: target i2c address
323 * @addr: address to read from
325 * @buffer: buffer for read data
326 * @len: no of bytes to be read
328 * Write to i2c memory.
330 static int __dw_i2c_write(struct i2c_regs *i2c_base, u8 dev, uint addr,
331 int alen, u8 *buffer, int len)
334 unsigned long start_time_tx;
336 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
338 * EEPROM chips that implement "address overflow" are ones
339 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
340 * address and the extra bits end up in the "chip address"
341 * bit slots. This makes a 24WC08 (1Kbyte) chip look like
342 * four 256 byte chips.
344 * Note that we consider the length of the address field to
345 * still be one byte because the extra address bits are
346 * hidden in the chip address.
348 dev |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
349 addr &= ~(CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW << (alen * 8));
351 debug("%s: fix addr_overflow: dev %02x addr %02x\n", __func__, dev,
355 if (i2c_xfer_init(i2c_base, dev, addr, alen))
358 start_time_tx = get_timer(0);
360 if (readl(&i2c_base->ic_status) & IC_STATUS_TFNF) {
362 writel(*buffer | IC_STOP,
363 &i2c_base->ic_cmd_data);
365 writel(*buffer, &i2c_base->ic_cmd_data);
368 start_time_tx = get_timer(0);
370 } else if (get_timer(start_time_tx) > (nb * I2C_BYTE_TO)) {
371 printf("Timed out. i2c write Failed\n");
376 return i2c_xfer_finish(i2c_base);
380 * __dw_i2c_init - Init function
381 * @speed: required i2c speed
382 * @slaveaddr: slave address for the device
384 * Initialization function.
386 static int __dw_i2c_init(struct i2c_regs *i2c_base, int speed, int slaveaddr)
391 ret = dw_i2c_enable(i2c_base, false);
395 writel(IC_CON_SD | IC_CON_RE | IC_CON_SPD_FS | IC_CON_MM,
397 writel(IC_RX_TL, &i2c_base->ic_rx_tl);
398 writel(IC_TX_TL, &i2c_base->ic_tx_tl);
399 writel(IC_STOP_DET, &i2c_base->ic_intr_mask);
400 #ifndef CONFIG_DM_I2C
401 __dw_i2c_set_bus_speed(i2c_base, NULL, speed, IC_CLK);
402 writel(slaveaddr, &i2c_base->ic_sar);
406 ret = dw_i2c_enable(i2c_base, true);
413 #ifndef CONFIG_DM_I2C
415 * The legacy I2C functions. These need to get removed once
416 * all users of this driver are converted to DM.
418 static struct i2c_regs *i2c_get_base(struct i2c_adapter *adap)
420 switch (adap->hwadapnr) {
421 #if CONFIG_SYS_I2C_BUS_MAX >= 4
423 return (struct i2c_regs *)CONFIG_SYS_I2C_BASE3;
425 #if CONFIG_SYS_I2C_BUS_MAX >= 3
427 return (struct i2c_regs *)CONFIG_SYS_I2C_BASE2;
429 #if CONFIG_SYS_I2C_BUS_MAX >= 2
431 return (struct i2c_regs *)CONFIG_SYS_I2C_BASE1;
434 return (struct i2c_regs *)CONFIG_SYS_I2C_BASE;
436 printf("Wrong I2C-adapter number %d\n", adap->hwadapnr);
442 static unsigned int dw_i2c_set_bus_speed(struct i2c_adapter *adap,
446 return __dw_i2c_set_bus_speed(i2c_get_base(adap), NULL, speed, IC_CLK);
449 static void dw_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
451 __dw_i2c_init(i2c_get_base(adap), speed, slaveaddr);
454 static int dw_i2c_read(struct i2c_adapter *adap, u8 dev, uint addr,
455 int alen, u8 *buffer, int len)
457 return __dw_i2c_read(i2c_get_base(adap), dev, addr, alen, buffer, len);
460 static int dw_i2c_write(struct i2c_adapter *adap, u8 dev, uint addr,
461 int alen, u8 *buffer, int len)
463 return __dw_i2c_write(i2c_get_base(adap), dev, addr, alen, buffer, len);
466 /* dw_i2c_probe - Probe the i2c chip */
467 static int dw_i2c_probe(struct i2c_adapter *adap, u8 dev)
469 struct i2c_regs *i2c_base = i2c_get_base(adap);
474 * Try to read the first location of the chip.
476 ret = __dw_i2c_read(i2c_base, dev, 0, 1, (uchar *)&tmp, 1);
478 dw_i2c_init(adap, adap->speed, adap->slaveaddr);
483 U_BOOT_I2C_ADAP_COMPLETE(dw_0, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
484 dw_i2c_write, dw_i2c_set_bus_speed,
485 CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE, 0)
487 #if CONFIG_SYS_I2C_BUS_MAX >= 2
488 U_BOOT_I2C_ADAP_COMPLETE(dw_1, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
489 dw_i2c_write, dw_i2c_set_bus_speed,
490 CONFIG_SYS_I2C_SPEED1, CONFIG_SYS_I2C_SLAVE1, 1)
493 #if CONFIG_SYS_I2C_BUS_MAX >= 3
494 U_BOOT_I2C_ADAP_COMPLETE(dw_2, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
495 dw_i2c_write, dw_i2c_set_bus_speed,
496 CONFIG_SYS_I2C_SPEED2, CONFIG_SYS_I2C_SLAVE2, 2)
499 #if CONFIG_SYS_I2C_BUS_MAX >= 4
500 U_BOOT_I2C_ADAP_COMPLETE(dw_3, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
501 dw_i2c_write, dw_i2c_set_bus_speed,
502 CONFIG_SYS_I2C_SPEED3, CONFIG_SYS_I2C_SLAVE3, 3)
505 #else /* CONFIG_DM_I2C */
506 /* The DM I2C functions */
508 static int designware_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
511 struct dw_i2c *i2c = dev_get_priv(bus);
514 debug("i2c_xfer: %d messages\n", nmsgs);
515 for (; nmsgs > 0; nmsgs--, msg++) {
516 debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
517 if (msg->flags & I2C_M_RD) {
518 ret = __dw_i2c_read(i2c->regs, msg->addr, 0, 0,
521 ret = __dw_i2c_write(i2c->regs, msg->addr, 0, 0,
525 debug("i2c_write: error sending\n");
533 static int designware_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
535 struct dw_i2c *i2c = dev_get_priv(bus);
538 #if CONFIG_IS_ENABLED(CLK)
539 rate = clk_get_rate(&i2c->clk);
540 if (IS_ERR_VALUE(rate))
548 return __dw_i2c_set_bus_speed(i2c->regs, i2c->scl_sda_cfg, speed,
552 static int designware_i2c_probe_chip(struct udevice *bus, uint chip_addr,
555 struct dw_i2c *i2c = dev_get_priv(bus);
556 struct i2c_regs *i2c_base = i2c->regs;
560 /* Try to read the first location of the chip */
561 ret = __dw_i2c_read(i2c_base, chip_addr, 0, 1, (uchar *)&tmp, 1);
563 __dw_i2c_init(i2c_base, 0, 0);
568 static int designware_i2c_probe(struct udevice *bus)
570 struct dw_i2c *priv = dev_get_priv(bus);
573 if (device_is_on_pci_bus(bus)) {
575 /* Save base address from PCI BAR */
576 priv->regs = (struct i2c_regs *)
577 dm_pci_map_bar(bus, PCI_BASE_ADDRESS_0, PCI_REGION_MEM);
579 /* Use BayTrail specific timing values */
580 priv->scl_sda_cfg = &byt_config;
584 priv->regs = (struct i2c_regs *)devfdt_get_addr_ptr(bus);
587 ret = reset_get_bulk(bus, &priv->resets);
589 dev_warn(bus, "Can't get reset: %d\n", ret);
591 reset_deassert_bulk(&priv->resets);
593 #if CONFIG_IS_ENABLED(CLK)
594 ret = clk_get_by_index(bus, 0, &priv->clk);
598 ret = clk_enable(&priv->clk);
599 if (ret && ret != -ENOSYS && ret != -ENOTSUPP) {
600 clk_free(&priv->clk);
601 dev_err(bus, "failed to enable clock\n");
606 return __dw_i2c_init(priv->regs, 0, 0);
609 static int designware_i2c_remove(struct udevice *dev)
611 struct dw_i2c *priv = dev_get_priv(dev);
613 #if CONFIG_IS_ENABLED(CLK)
614 clk_disable(&priv->clk);
615 clk_free(&priv->clk);
618 return reset_release_bulk(&priv->resets);
621 static int designware_i2c_bind(struct udevice *dev)
623 static int num_cards;
626 /* Create a unique device name for PCI type devices */
627 if (device_is_on_pci_bus(dev)) {
630 * Setting req_seq in the driver is probably not recommended.
631 * But without a DT alias the number is not configured. And
632 * using this driver is impossible for PCIe I2C devices.
633 * This can be removed, once a better (correct) way for this
634 * is found and implemented.
636 dev->req_seq = num_cards;
637 sprintf(name, "i2c_designware#%u", num_cards++);
638 device_set_name(dev, name);
644 static const struct dm_i2c_ops designware_i2c_ops = {
645 .xfer = designware_i2c_xfer,
646 .probe_chip = designware_i2c_probe_chip,
647 .set_bus_speed = designware_i2c_set_bus_speed,
650 static const struct udevice_id designware_i2c_ids[] = {
651 { .compatible = "snps,designware-i2c" },
655 U_BOOT_DRIVER(i2c_designware) = {
656 .name = "i2c_designware",
658 .of_match = designware_i2c_ids,
659 .bind = designware_i2c_bind,
660 .probe = designware_i2c_probe,
661 .priv_auto_alloc_size = sizeof(struct dw_i2c),
662 .remove = designware_i2c_remove,
663 .flags = DM_FLAG_OS_PREPARE,
664 .ops = &designware_i2c_ops,
668 static struct pci_device_id designware_pci_supported[] = {
669 /* Intel BayTrail has 7 I2C controller located on the PCI bus */
670 { PCI_VDEVICE(INTEL, 0x0f41) },
671 { PCI_VDEVICE(INTEL, 0x0f42) },
672 { PCI_VDEVICE(INTEL, 0x0f43) },
673 { PCI_VDEVICE(INTEL, 0x0f44) },
674 { PCI_VDEVICE(INTEL, 0x0f45) },
675 { PCI_VDEVICE(INTEL, 0x0f46) },
676 { PCI_VDEVICE(INTEL, 0x0f47) },
680 U_BOOT_PCI_DEVICE(i2c_designware, designware_pci_supported);
683 #endif /* CONFIG_DM_I2C */