xref: /openbmc/u-boot/drivers/i2c/mxc_i2c.c (revision ae485b54)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * i2c driver for Freescale i.MX series
4  *
5  * (c) 2007 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
6  * (c) 2011 Marek Vasut <marek.vasut@gmail.com>
7  *
8  * Based on i2c-imx.c from linux kernel:
9  *  Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de>
10  *  Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de>
11  *  Copyright (C) 2007 RightHand Technologies, Inc.
12  *  Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
13  *
14  */
15 
16 #include <common.h>
17 #include <asm/arch/clock.h>
18 #include <asm/arch/imx-regs.h>
19 #include <linux/errno.h>
20 #include <asm/mach-imx/mxc_i2c.h>
21 #include <asm/io.h>
22 #include <i2c.h>
23 #include <watchdog.h>
24 #include <dm.h>
25 #include <dm/pinctrl.h>
26 #include <fdtdec.h>
27 
28 DECLARE_GLOBAL_DATA_PTR;
29 
30 #define I2C_QUIRK_FLAG		(1 << 0)
31 
32 #define IMX_I2C_REGSHIFT	2
33 #define VF610_I2C_REGSHIFT	0
34 
35 #define I2C_EARLY_INIT_INDEX		0
36 #ifdef CONFIG_SYS_I2C_IFDR_DIV
37 #define I2C_IFDR_DIV_CONSERVATIVE	CONFIG_SYS_I2C_IFDR_DIV
38 #else
39 #define I2C_IFDR_DIV_CONSERVATIVE	0x7e
40 #endif
41 
42 /* Register index */
43 #define IADR	0
44 #define IFDR	1
45 #define I2CR	2
46 #define I2SR	3
47 #define I2DR	4
48 
49 #define I2CR_IIEN	(1 << 6)
50 #define I2CR_MSTA	(1 << 5)
51 #define I2CR_MTX	(1 << 4)
52 #define I2CR_TX_NO_AK	(1 << 3)
53 #define I2CR_RSTA	(1 << 2)
54 
55 #define I2SR_ICF	(1 << 7)
56 #define I2SR_IBB	(1 << 5)
57 #define I2SR_IAL	(1 << 4)
58 #define I2SR_IIF	(1 << 1)
59 #define I2SR_RX_NO_AK	(1 << 0)
60 
61 #ifdef I2C_QUIRK_REG
62 #define I2CR_IEN	(0 << 7)
63 #define I2CR_IDIS	(1 << 7)
64 #define I2SR_IIF_CLEAR	(1 << 1)
65 #else
66 #define I2CR_IEN	(1 << 7)
67 #define I2CR_IDIS	(0 << 7)
68 #define I2SR_IIF_CLEAR	(0 << 1)
69 #endif
70 
71 #ifdef I2C_QUIRK_REG
72 static u16 i2c_clk_div[60][2] = {
73 	{ 20,	0x00 }, { 22,	0x01 }, { 24,	0x02 }, { 26,	0x03 },
74 	{ 28,	0x04 },	{ 30,	0x05 },	{ 32,	0x09 }, { 34,	0x06 },
75 	{ 36,	0x0A }, { 40,	0x07 }, { 44,	0x0C }, { 48,	0x0D },
76 	{ 52,	0x43 },	{ 56,	0x0E }, { 60,	0x45 }, { 64,	0x12 },
77 	{ 68,	0x0F },	{ 72,	0x13 },	{ 80,	0x14 },	{ 88,	0x15 },
78 	{ 96,	0x19 },	{ 104,	0x16 },	{ 112,	0x1A },	{ 128,	0x17 },
79 	{ 136,	0x4F }, { 144,	0x1C },	{ 160,	0x1D }, { 176,	0x55 },
80 	{ 192,	0x1E }, { 208,	0x56 },	{ 224,	0x22 }, { 228,	0x24 },
81 	{ 240,	0x1F },	{ 256,	0x23 }, { 288,	0x5C },	{ 320,	0x25 },
82 	{ 384,	0x26 }, { 448,	0x2A },	{ 480,	0x27 }, { 512,	0x2B },
83 	{ 576,	0x2C },	{ 640,	0x2D },	{ 768,	0x31 }, { 896,	0x32 },
84 	{ 960,	0x2F },	{ 1024,	0x33 },	{ 1152,	0x34 }, { 1280,	0x35 },
85 	{ 1536,	0x36 }, { 1792,	0x3A },	{ 1920,	0x37 },	{ 2048,	0x3B },
86 	{ 2304,	0x3C },	{ 2560,	0x3D },	{ 3072,	0x3E }, { 3584,	0x7A },
87 	{ 3840,	0x3F }, { 4096,	0x7B }, { 5120,	0x7D },	{ 6144,	0x7E },
88 };
89 #else
90 static u16 i2c_clk_div[50][2] = {
91 	{ 22,	0x20 }, { 24,	0x21 }, { 26,	0x22 }, { 28,	0x23 },
92 	{ 30,	0x00 }, { 32,	0x24 }, { 36,	0x25 }, { 40,	0x26 },
93 	{ 42,	0x03 }, { 44,	0x27 }, { 48,	0x28 }, { 52,	0x05 },
94 	{ 56,	0x29 }, { 60,	0x06 }, { 64,	0x2A }, { 72,	0x2B },
95 	{ 80,	0x2C }, { 88,	0x09 }, { 96,	0x2D }, { 104,	0x0A },
96 	{ 112,	0x2E }, { 128,	0x2F }, { 144,	0x0C }, { 160,	0x30 },
97 	{ 192,	0x31 }, { 224,	0x32 }, { 240,	0x0F }, { 256,	0x33 },
98 	{ 288,	0x10 }, { 320,	0x34 }, { 384,	0x35 }, { 448,	0x36 },
99 	{ 480,	0x13 }, { 512,	0x37 }, { 576,	0x14 }, { 640,	0x38 },
100 	{ 768,	0x39 }, { 896,	0x3A }, { 960,	0x17 }, { 1024,	0x3B },
101 	{ 1152,	0x18 }, { 1280,	0x3C }, { 1536,	0x3D }, { 1792,	0x3E },
102 	{ 1920,	0x1B }, { 2048,	0x3F }, { 2304,	0x1C }, { 2560,	0x1D },
103 	{ 3072,	0x1E }, { 3840,	0x1F }
104 };
105 #endif
106 
107 #ifndef CONFIG_SYS_MXC_I2C1_SPEED
108 #define CONFIG_SYS_MXC_I2C1_SPEED 100000
109 #endif
110 #ifndef CONFIG_SYS_MXC_I2C2_SPEED
111 #define CONFIG_SYS_MXC_I2C2_SPEED 100000
112 #endif
113 #ifndef CONFIG_SYS_MXC_I2C3_SPEED
114 #define CONFIG_SYS_MXC_I2C3_SPEED 100000
115 #endif
116 #ifndef CONFIG_SYS_MXC_I2C4_SPEED
117 #define CONFIG_SYS_MXC_I2C4_SPEED 100000
118 #endif
119 
120 #ifndef CONFIG_SYS_MXC_I2C1_SLAVE
121 #define CONFIG_SYS_MXC_I2C1_SLAVE 0
122 #endif
123 #ifndef CONFIG_SYS_MXC_I2C2_SLAVE
124 #define CONFIG_SYS_MXC_I2C2_SLAVE 0
125 #endif
126 #ifndef CONFIG_SYS_MXC_I2C3_SLAVE
127 #define CONFIG_SYS_MXC_I2C3_SLAVE 0
128 #endif
129 #ifndef CONFIG_SYS_MXC_I2C4_SLAVE
130 #define CONFIG_SYS_MXC_I2C4_SLAVE 0
131 #endif
132 
133 /*
134  * Calculate and set proper clock divider
135  */
136 static uint8_t i2c_imx_get_clk(struct mxc_i2c_bus *i2c_bus, unsigned int rate)
137 {
138 	unsigned int i2c_clk_rate;
139 	unsigned int div;
140 	u8 clk_div;
141 
142 #if defined(CONFIG_MX31)
143 	struct clock_control_regs *sc_regs =
144 		(struct clock_control_regs *)CCM_BASE;
145 
146 	/* start the required I2C clock */
147 	writel(readl(&sc_regs->cgr0) | (3 << CONFIG_SYS_I2C_CLK_OFFSET),
148 		&sc_regs->cgr0);
149 #endif
150 
151 	/* Divider value calculation */
152 	i2c_clk_rate = mxc_get_clock(MXC_I2C_CLK);
153 	div = (i2c_clk_rate + rate - 1) / rate;
154 	if (div < i2c_clk_div[0][0])
155 		clk_div = 0;
156 	else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
157 		clk_div = ARRAY_SIZE(i2c_clk_div) - 1;
158 	else
159 		for (clk_div = 0; i2c_clk_div[clk_div][0] < div; clk_div++)
160 			;
161 
162 	/* Store divider value */
163 	return clk_div;
164 }
165 
166 /*
167  * Set I2C Bus speed
168  */
169 static int bus_i2c_set_bus_speed(struct mxc_i2c_bus *i2c_bus, int speed)
170 {
171 	ulong base = i2c_bus->base;
172 	bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
173 	u8 clk_idx = i2c_imx_get_clk(i2c_bus, speed);
174 	u8 idx = i2c_clk_div[clk_idx][1];
175 	int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
176 
177 	if (!base)
178 		return -EINVAL;
179 
180 	/* Store divider value */
181 	writeb(idx, base + (IFDR << reg_shift));
182 
183 	/* Reset module */
184 	writeb(I2CR_IDIS, base + (I2CR << reg_shift));
185 	writeb(0, base + (I2SR << reg_shift));
186 	return 0;
187 }
188 
189 #define ST_BUS_IDLE (0 | (I2SR_IBB << 8))
190 #define ST_BUS_BUSY (I2SR_IBB | (I2SR_IBB << 8))
191 #define ST_IIF (I2SR_IIF | (I2SR_IIF << 8))
192 
193 static int wait_for_sr_state(struct mxc_i2c_bus *i2c_bus, unsigned state)
194 {
195 	unsigned sr;
196 	ulong elapsed;
197 	bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
198 	int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
199 	ulong base = i2c_bus->base;
200 	ulong start_time = get_timer(0);
201 	for (;;) {
202 		sr = readb(base + (I2SR << reg_shift));
203 		if (sr & I2SR_IAL) {
204 			if (quirk)
205 				writeb(sr | I2SR_IAL, base +
206 				       (I2SR << reg_shift));
207 			else
208 				writeb(sr & ~I2SR_IAL, base +
209 				       (I2SR << reg_shift));
210 			printf("%s: Arbitration lost sr=%x cr=%x state=%x\n",
211 				__func__, sr, readb(base + (I2CR << reg_shift)),
212 				state);
213 			return -ERESTART;
214 		}
215 		if ((sr & (state >> 8)) == (unsigned char)state)
216 			return sr;
217 		WATCHDOG_RESET();
218 		elapsed = get_timer(start_time);
219 		if (elapsed > (CONFIG_SYS_HZ / 10))	/* .1 seconds */
220 			break;
221 	}
222 	printf("%s: failed sr=%x cr=%x state=%x\n", __func__,
223 	       sr, readb(base + (I2CR << reg_shift)), state);
224 	return -ETIMEDOUT;
225 }
226 
227 static int tx_byte(struct mxc_i2c_bus *i2c_bus, u8 byte)
228 {
229 	int ret;
230 	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
231 			VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
232 	ulong base = i2c_bus->base;
233 
234 	writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
235 	writeb(byte, base + (I2DR << reg_shift));
236 
237 	ret = wait_for_sr_state(i2c_bus, ST_IIF);
238 	if (ret < 0)
239 		return ret;
240 	if (ret & I2SR_RX_NO_AK)
241 		return -EREMOTEIO;
242 	return 0;
243 }
244 
245 /*
246  * Stub implementations for outer i2c slave operations.
247  */
248 void __i2c_force_reset_slave(void)
249 {
250 }
251 void i2c_force_reset_slave(void)
252 	__attribute__((weak, alias("__i2c_force_reset_slave")));
253 
254 /*
255  * Stop I2C transaction
256  */
257 static void i2c_imx_stop(struct mxc_i2c_bus *i2c_bus)
258 {
259 	int ret;
260 	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
261 			VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
262 	ulong base = i2c_bus->base;
263 	unsigned int temp = readb(base + (I2CR << reg_shift));
264 
265 	temp &= ~(I2CR_MSTA | I2CR_MTX);
266 	writeb(temp, base + (I2CR << reg_shift));
267 	ret = wait_for_sr_state(i2c_bus, ST_BUS_IDLE);
268 	if (ret < 0)
269 		printf("%s:trigger stop failed\n", __func__);
270 }
271 
272 /*
273  * Send start signal, chip address and
274  * write register address
275  */
276 static int i2c_init_transfer_(struct mxc_i2c_bus *i2c_bus, u8 chip,
277 			      u32 addr, int alen)
278 {
279 	unsigned int temp;
280 	int ret;
281 	bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
282 	ulong base = i2c_bus->base;
283 	int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
284 
285 	/* Reset i2c slave */
286 	i2c_force_reset_slave();
287 
288 	/* Enable I2C controller */
289 	if (quirk)
290 		ret = readb(base + (I2CR << reg_shift)) & I2CR_IDIS;
291 	else
292 		ret = !(readb(base + (I2CR << reg_shift)) & I2CR_IEN);
293 
294 	if (ret) {
295 		writeb(I2CR_IEN, base + (I2CR << reg_shift));
296 		/* Wait for controller to be stable */
297 		udelay(50);
298 	}
299 
300 	if (readb(base + (IADR << reg_shift)) == (chip << 1))
301 		writeb((chip << 1) ^ 2, base + (IADR << reg_shift));
302 	writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
303 	ret = wait_for_sr_state(i2c_bus, ST_BUS_IDLE);
304 	if (ret < 0)
305 		return ret;
306 
307 	/* Start I2C transaction */
308 	temp = readb(base + (I2CR << reg_shift));
309 	temp |= I2CR_MSTA;
310 	writeb(temp, base + (I2CR << reg_shift));
311 
312 	ret = wait_for_sr_state(i2c_bus, ST_BUS_BUSY);
313 	if (ret < 0)
314 		return ret;
315 
316 	temp |= I2CR_MTX | I2CR_TX_NO_AK;
317 	writeb(temp, base + (I2CR << reg_shift));
318 
319 	if (alen >= 0)	{
320 		/* write slave address */
321 		ret = tx_byte(i2c_bus, chip << 1);
322 		if (ret < 0)
323 			return ret;
324 
325 		while (alen--) {
326 			ret = tx_byte(i2c_bus, (addr >> (alen * 8)) & 0xff);
327 			if (ret < 0)
328 				return ret;
329 		}
330 	}
331 
332 	return 0;
333 }
334 
335 #ifndef CONFIG_DM_I2C
336 int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
337 {
338 	if (i2c_bus && i2c_bus->idle_bus_fn)
339 		return i2c_bus->idle_bus_fn(i2c_bus->idle_bus_data);
340 	return 0;
341 }
342 #else
343 /*
344  * See Linux Documentation/devicetree/bindings/i2c/i2c-imx.txt
345  * "
346  *  scl-gpios: specify the gpio related to SCL pin
347  *  sda-gpios: specify the gpio related to SDA pin
348  *  add pinctrl to configure i2c pins to gpio function for i2c
349  *  bus recovery, call it "gpio" state
350  * "
351  *
352  * The i2c_idle_bus is an implementation following Linux Kernel.
353  */
354 int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
355 {
356 	struct udevice *bus = i2c_bus->bus;
357 	struct gpio_desc *scl_gpio = &i2c_bus->scl_gpio;
358 	struct gpio_desc *sda_gpio = &i2c_bus->sda_gpio;
359 	int sda, scl;
360 	int i, ret = 0;
361 	ulong elapsed, start_time;
362 
363 	if (pinctrl_select_state(bus, "gpio")) {
364 		dev_dbg(bus, "Can not to switch to use gpio pinmux\n");
365 		/*
366 		 * GPIO pinctrl for i2c force idle is not a must,
367 		 * but it is strongly recommended to be used.
368 		 * Because it can help you to recover from bad
369 		 * i2c bus state. Do not return failure, because
370 		 * it is not a must.
371 		 */
372 		return 0;
373 	}
374 
375 	dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
376 	dm_gpio_set_dir_flags(sda_gpio, GPIOD_IS_IN);
377 	scl = dm_gpio_get_value(scl_gpio);
378 	sda = dm_gpio_get_value(sda_gpio);
379 
380 	if ((sda & scl) == 1)
381 		goto exit;		/* Bus is idle already */
382 
383 	/* Send high and low on the SCL line */
384 	for (i = 0; i < 9; i++) {
385 		dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_OUT);
386 		dm_gpio_set_value(scl_gpio, 0);
387 		udelay(50);
388 		dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
389 		udelay(50);
390 	}
391 	start_time = get_timer(0);
392 	for (;;) {
393 		dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
394 		dm_gpio_set_dir_flags(sda_gpio, GPIOD_IS_IN);
395 		scl = dm_gpio_get_value(scl_gpio);
396 		sda = dm_gpio_get_value(sda_gpio);
397 		if ((sda & scl) == 1)
398 			break;
399 		WATCHDOG_RESET();
400 		elapsed = get_timer(start_time);
401 		if (elapsed > (CONFIG_SYS_HZ / 5)) {	/* .2 seconds */
402 			ret = -EBUSY;
403 			printf("%s: failed to clear bus, sda=%d scl=%d\n", __func__, sda, scl);
404 			break;
405 		}
406 	}
407 
408 exit:
409 	pinctrl_select_state(bus, "default");
410 	return ret;
411 }
412 #endif
413 
414 static int i2c_init_transfer(struct mxc_i2c_bus *i2c_bus, u8 chip,
415 			     u32 addr, int alen)
416 {
417 	int retry;
418 	int ret;
419 	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
420 			VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
421 
422 	if (!i2c_bus->base)
423 		return -EINVAL;
424 
425 	for (retry = 0; retry < 3; retry++) {
426 		ret = i2c_init_transfer_(i2c_bus, chip, addr, alen);
427 		if (ret >= 0)
428 			return 0;
429 		i2c_imx_stop(i2c_bus);
430 		if (ret == -EREMOTEIO)
431 			return ret;
432 
433 		printf("%s: failed for chip 0x%x retry=%d\n", __func__, chip,
434 				retry);
435 		if (ret != -ERESTART)
436 			/* Disable controller */
437 			writeb(I2CR_IDIS, i2c_bus->base + (I2CR << reg_shift));
438 		udelay(100);
439 		if (i2c_idle_bus(i2c_bus) < 0)
440 			break;
441 	}
442 	printf("%s: give up i2c_regs=0x%lx\n", __func__, i2c_bus->base);
443 	return ret;
444 }
445 
446 
447 static int i2c_write_data(struct mxc_i2c_bus *i2c_bus, u8 chip, const u8 *buf,
448 			  int len)
449 {
450 	int i, ret = 0;
451 
452 	debug("i2c_write_data: chip=0x%x, len=0x%x\n", chip, len);
453 	debug("write_data: ");
454 	/* use rc for counter */
455 	for (i = 0; i < len; ++i)
456 		debug(" 0x%02x", buf[i]);
457 	debug("\n");
458 
459 	for (i = 0; i < len; i++) {
460 		ret = tx_byte(i2c_bus, buf[i]);
461 		if (ret < 0) {
462 			debug("i2c_write_data(): rc=%d\n", ret);
463 			break;
464 		}
465 	}
466 
467 	return ret;
468 }
469 
470 static int i2c_read_data(struct mxc_i2c_bus *i2c_bus, uchar chip, uchar *buf,
471 			 int len)
472 {
473 	int ret;
474 	unsigned int temp;
475 	int i;
476 	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
477 			VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
478 	ulong base = i2c_bus->base;
479 
480 	debug("i2c_read_data: chip=0x%x, len=0x%x\n", chip, len);
481 
482 	/* setup bus to read data */
483 	temp = readb(base + (I2CR << reg_shift));
484 	temp &= ~(I2CR_MTX | I2CR_TX_NO_AK);
485 	if (len == 1)
486 		temp |= I2CR_TX_NO_AK;
487 	writeb(temp, base + (I2CR << reg_shift));
488 	writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
489 	/* dummy read to clear ICF */
490 	readb(base + (I2DR << reg_shift));
491 
492 	/* read data */
493 	for (i = 0; i < len; i++) {
494 		ret = wait_for_sr_state(i2c_bus, ST_IIF);
495 		if (ret < 0) {
496 			debug("i2c_read_data(): ret=%d\n", ret);
497 			i2c_imx_stop(i2c_bus);
498 			return ret;
499 		}
500 
501 		/*
502 		 * It must generate STOP before read I2DR to prevent
503 		 * controller from generating another clock cycle
504 		 */
505 		if (i == (len - 1)) {
506 			i2c_imx_stop(i2c_bus);
507 		} else if (i == (len - 2)) {
508 			temp = readb(base + (I2CR << reg_shift));
509 			temp |= I2CR_TX_NO_AK;
510 			writeb(temp, base + (I2CR << reg_shift));
511 		}
512 		writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
513 		buf[i] = readb(base + (I2DR << reg_shift));
514 	}
515 
516 	/* reuse ret for counter*/
517 	for (ret = 0; ret < len; ++ret)
518 		debug(" 0x%02x", buf[ret]);
519 	debug("\n");
520 
521 	i2c_imx_stop(i2c_bus);
522 	return 0;
523 }
524 
525 #ifndef CONFIG_DM_I2C
526 /*
527  * Read data from I2C device
528  */
529 static int bus_i2c_read(struct mxc_i2c_bus *i2c_bus, u8 chip, u32 addr,
530 			int alen, u8 *buf, int len)
531 {
532 	int ret = 0;
533 	u32 temp;
534 	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
535 		VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
536 	ulong base = i2c_bus->base;
537 
538 	ret = i2c_init_transfer(i2c_bus, chip, addr, alen);
539 	if (ret < 0)
540 		return ret;
541 
542 	if (alen >= 0) {
543 		temp = readb(base + (I2CR << reg_shift));
544 		temp |= I2CR_RSTA;
545 		writeb(temp, base + (I2CR << reg_shift));
546 	}
547 
548 	ret = tx_byte(i2c_bus, (chip << 1) | 1);
549 	if (ret < 0) {
550 		i2c_imx_stop(i2c_bus);
551 		return ret;
552 	}
553 
554 	ret = i2c_read_data(i2c_bus, chip, buf, len);
555 
556 	i2c_imx_stop(i2c_bus);
557 	return ret;
558 }
559 
560 /*
561  * Write data to I2C device
562  */
563 static int bus_i2c_write(struct mxc_i2c_bus *i2c_bus, u8 chip, u32 addr,
564 			 int alen, const u8 *buf, int len)
565 {
566 	int ret = 0;
567 
568 	ret = i2c_init_transfer(i2c_bus, chip, addr, alen);
569 	if (ret < 0)
570 		return ret;
571 
572 	ret = i2c_write_data(i2c_bus, chip, buf, len);
573 
574 	i2c_imx_stop(i2c_bus);
575 
576 	return ret;
577 }
578 
579 #if !defined(I2C2_BASE_ADDR)
580 #define I2C2_BASE_ADDR	0
581 #endif
582 
583 #if !defined(I2C3_BASE_ADDR)
584 #define I2C3_BASE_ADDR	0
585 #endif
586 
587 #if !defined(I2C4_BASE_ADDR)
588 #define I2C4_BASE_ADDR	0
589 #endif
590 
591 #if !defined(I2C5_BASE_ADDR)
592 #define I2C5_BASE_ADDR 0
593 #endif
594 
595 #if !defined(I2C6_BASE_ADDR)
596 #define I2C6_BASE_ADDR 0
597 #endif
598 
599 #if !defined(I2C7_BASE_ADDR)
600 #define I2C7_BASE_ADDR 0
601 #endif
602 
603 #if !defined(I2C8_BASE_ADDR)
604 #define I2C8_BASE_ADDR 0
605 #endif
606 
607 static struct mxc_i2c_bus mxc_i2c_buses[] = {
608 #if defined(CONFIG_ARCH_LS1021A) || defined(CONFIG_VF610) || \
609 	defined(CONFIG_FSL_LAYERSCAPE)
610 	{ 0, I2C1_BASE_ADDR, I2C_QUIRK_FLAG },
611 	{ 1, I2C2_BASE_ADDR, I2C_QUIRK_FLAG },
612 	{ 2, I2C3_BASE_ADDR, I2C_QUIRK_FLAG },
613 	{ 3, I2C4_BASE_ADDR, I2C_QUIRK_FLAG },
614 	{ 4, I2C5_BASE_ADDR, I2C_QUIRK_FLAG },
615 	{ 5, I2C6_BASE_ADDR, I2C_QUIRK_FLAG },
616 	{ 6, I2C7_BASE_ADDR, I2C_QUIRK_FLAG },
617 	{ 7, I2C8_BASE_ADDR, I2C_QUIRK_FLAG },
618 #else
619 	{ 0, I2C1_BASE_ADDR, 0 },
620 	{ 1, I2C2_BASE_ADDR, 0 },
621 	{ 2, I2C3_BASE_ADDR, 0 },
622 	{ 3, I2C4_BASE_ADDR, 0 },
623 	{ 4, I2C5_BASE_ADDR, 0 },
624 	{ 5, I2C6_BASE_ADDR, 0 },
625 	{ 6, I2C7_BASE_ADDR, 0 },
626 	{ 7, I2C8_BASE_ADDR, 0 },
627 #endif
628 };
629 
630 struct mxc_i2c_bus *i2c_get_base(struct i2c_adapter *adap)
631 {
632 	return &mxc_i2c_buses[adap->hwadapnr];
633 }
634 
635 static int mxc_i2c_read(struct i2c_adapter *adap, uint8_t chip,
636 				uint addr, int alen, uint8_t *buffer,
637 				int len)
638 {
639 	return bus_i2c_read(i2c_get_base(adap), chip, addr, alen, buffer, len);
640 }
641 
642 static int mxc_i2c_write(struct i2c_adapter *adap, uint8_t chip,
643 				uint addr, int alen, uint8_t *buffer,
644 				int len)
645 {
646 	return bus_i2c_write(i2c_get_base(adap), chip, addr, alen, buffer, len);
647 }
648 
649 /*
650  * Test if a chip at a given address responds (probe the chip)
651  */
652 static int mxc_i2c_probe(struct i2c_adapter *adap, uint8_t chip)
653 {
654 	return bus_i2c_write(i2c_get_base(adap), chip, 0, 0, NULL, 0);
655 }
656 
657 int __enable_i2c_clk(unsigned char enable, unsigned i2c_num)
658 {
659 	return 1;
660 }
661 int enable_i2c_clk(unsigned char enable, unsigned i2c_num)
662 	__attribute__((weak, alias("__enable_i2c_clk")));
663 
664 void bus_i2c_init(int index, int speed, int unused,
665 		  int (*idle_bus_fn)(void *p), void *idle_bus_data)
666 {
667 	int ret;
668 
669 	if (index >= ARRAY_SIZE(mxc_i2c_buses)) {
670 		debug("Error i2c index\n");
671 		return;
672 	}
673 
674 	/*
675 	 * Warning: Be careful to allow the assignment to a static
676 	 * variable here. This function could be called while U-Boot is
677 	 * still running in flash memory. So such assignment is equal
678 	 * to write data to flash without erasing.
679 	 */
680 	if (idle_bus_fn)
681 		mxc_i2c_buses[index].idle_bus_fn = idle_bus_fn;
682 	if (idle_bus_data)
683 		mxc_i2c_buses[index].idle_bus_data = idle_bus_data;
684 
685 	ret = enable_i2c_clk(1, index);
686 	if (ret < 0) {
687 		debug("I2C-%d clk fail to enable.\n", index);
688 		return;
689 	}
690 
691 	bus_i2c_set_bus_speed(&mxc_i2c_buses[index], speed);
692 }
693 
694 /*
695  * Early init I2C for prepare read the clk through I2C.
696  */
697 void i2c_early_init_f(void)
698 {
699 	ulong base = mxc_i2c_buses[I2C_EARLY_INIT_INDEX].base;
700 	bool quirk = mxc_i2c_buses[I2C_EARLY_INIT_INDEX].driver_data
701 					& I2C_QUIRK_FLAG ? true : false;
702 	int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
703 
704 	/* Set I2C divider value */
705 	writeb(I2C_IFDR_DIV_CONSERVATIVE, base + (IFDR << reg_shift));
706 	/* Reset module */
707 	writeb(I2CR_IDIS, base + (I2CR << reg_shift));
708 	writeb(0, base + (I2SR << reg_shift));
709 	/* Enable I2C */
710 	writeb(I2CR_IEN, base + (I2CR << reg_shift));
711 }
712 
713 /*
714  * Init I2C Bus
715  */
716 static void mxc_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
717 {
718 	bus_i2c_init(adap->hwadapnr, speed, slaveaddr, NULL, NULL);
719 }
720 
721 /*
722  * Set I2C Speed
723  */
724 static u32 mxc_i2c_set_bus_speed(struct i2c_adapter *adap, uint speed)
725 {
726 	return bus_i2c_set_bus_speed(i2c_get_base(adap), speed);
727 }
728 
729 /*
730  * Register mxc i2c adapters
731  */
732 #ifdef CONFIG_SYS_I2C_MXC_I2C1
733 U_BOOT_I2C_ADAP_COMPLETE(mxc0, mxc_i2c_init, mxc_i2c_probe,
734 			 mxc_i2c_read, mxc_i2c_write,
735 			 mxc_i2c_set_bus_speed,
736 			 CONFIG_SYS_MXC_I2C1_SPEED,
737 			 CONFIG_SYS_MXC_I2C1_SLAVE, 0)
738 #endif
739 
740 #ifdef CONFIG_SYS_I2C_MXC_I2C2
741 U_BOOT_I2C_ADAP_COMPLETE(mxc1, mxc_i2c_init, mxc_i2c_probe,
742 			 mxc_i2c_read, mxc_i2c_write,
743 			 mxc_i2c_set_bus_speed,
744 			 CONFIG_SYS_MXC_I2C2_SPEED,
745 			 CONFIG_SYS_MXC_I2C2_SLAVE, 1)
746 #endif
747 
748 #ifdef CONFIG_SYS_I2C_MXC_I2C3
749 U_BOOT_I2C_ADAP_COMPLETE(mxc2, mxc_i2c_init, mxc_i2c_probe,
750 			 mxc_i2c_read, mxc_i2c_write,
751 			 mxc_i2c_set_bus_speed,
752 			 CONFIG_SYS_MXC_I2C3_SPEED,
753 			 CONFIG_SYS_MXC_I2C3_SLAVE, 2)
754 #endif
755 
756 #ifdef CONFIG_SYS_I2C_MXC_I2C4
757 U_BOOT_I2C_ADAP_COMPLETE(mxc3, mxc_i2c_init, mxc_i2c_probe,
758 			 mxc_i2c_read, mxc_i2c_write,
759 			 mxc_i2c_set_bus_speed,
760 			 CONFIG_SYS_MXC_I2C4_SPEED,
761 			 CONFIG_SYS_MXC_I2C4_SLAVE, 3)
762 #endif
763 
764 #ifdef CONFIG_SYS_I2C_MXC_I2C5
765 U_BOOT_I2C_ADAP_COMPLETE(mxc4, mxc_i2c_init, mxc_i2c_probe,
766 			 mxc_i2c_read, mxc_i2c_write,
767 			 mxc_i2c_set_bus_speed,
768 			 CONFIG_SYS_MXC_I2C5_SPEED,
769 			 CONFIG_SYS_MXC_I2C5_SLAVE, 4)
770 #endif
771 
772 #ifdef CONFIG_SYS_I2C_MXC_I2C6
773 U_BOOT_I2C_ADAP_COMPLETE(mxc5, mxc_i2c_init, mxc_i2c_probe,
774 			 mxc_i2c_read, mxc_i2c_write,
775 			 mxc_i2c_set_bus_speed,
776 			 CONFIG_SYS_MXC_I2C6_SPEED,
777 			 CONFIG_SYS_MXC_I2C6_SLAVE, 5)
778 #endif
779 
780 #ifdef CONFIG_SYS_I2C_MXC_I2C7
781 U_BOOT_I2C_ADAP_COMPLETE(mxc6, mxc_i2c_init, mxc_i2c_probe,
782 			 mxc_i2c_read, mxc_i2c_write,
783 			 mxc_i2c_set_bus_speed,
784 			 CONFIG_SYS_MXC_I2C7_SPEED,
785 			 CONFIG_SYS_MXC_I2C7_SLAVE, 6)
786 #endif
787 
788 #ifdef CONFIG_SYS_I2C_MXC_I2C8
789 U_BOOT_I2C_ADAP_COMPLETE(mxc7, mxc_i2c_init, mxc_i2c_probe,
790 			 mxc_i2c_read, mxc_i2c_write,
791 			 mxc_i2c_set_bus_speed,
792 			 CONFIG_SYS_MXC_I2C8_SPEED,
793 			 CONFIG_SYS_MXC_I2C8_SLAVE, 7)
794 #endif
795 
796 #else
797 
798 static int mxc_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
799 {
800 	struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
801 
802 	return bus_i2c_set_bus_speed(i2c_bus, speed);
803 }
804 
805 static int mxc_i2c_probe(struct udevice *bus)
806 {
807 	struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
808 	const void *fdt = gd->fdt_blob;
809 	int node = dev_of_offset(bus);
810 	fdt_addr_t addr;
811 	int ret, ret2;
812 
813 	i2c_bus->driver_data = dev_get_driver_data(bus);
814 
815 	addr = devfdt_get_addr(bus);
816 	if (addr == FDT_ADDR_T_NONE)
817 		return -EINVAL;
818 
819 	i2c_bus->base = addr;
820 	i2c_bus->index = bus->seq;
821 	i2c_bus->bus = bus;
822 
823 	/* Enable clk */
824 	ret = enable_i2c_clk(1, bus->seq);
825 	if (ret < 0)
826 		return ret;
827 
828 	/*
829 	 * See Documentation/devicetree/bindings/i2c/i2c-imx.txt
830 	 * Use gpio to force bus idle when necessary.
831 	 */
832 	ret = fdt_stringlist_search(fdt, node, "pinctrl-names", "gpio");
833 	if (ret < 0) {
834 		debug("i2c bus %d at 0x%2lx, no gpio pinctrl state.\n", bus->seq, i2c_bus->base);
835 	} else {
836 		ret = gpio_request_by_name_nodev(offset_to_ofnode(node),
837 				"scl-gpios", 0, &i2c_bus->scl_gpio,
838 				GPIOD_IS_OUT);
839 		ret2 = gpio_request_by_name_nodev(offset_to_ofnode(node),
840 				"sda-gpios", 0, &i2c_bus->sda_gpio,
841 				GPIOD_IS_OUT);
842 		if (!dm_gpio_is_valid(&i2c_bus->sda_gpio) ||
843 		    !dm_gpio_is_valid(&i2c_bus->scl_gpio) ||
844 		    ret || ret2) {
845 			dev_err(dev, "i2c bus %d at %lu, fail to request scl/sda gpio\n", bus->seq, i2c_bus->base);
846 			return -EINVAL;
847 		}
848 	}
849 
850 	ret = i2c_idle_bus(i2c_bus);
851 	if (ret < 0) {
852 		/* Disable clk */
853 		enable_i2c_clk(0, bus->seq);
854 		return ret;
855 	}
856 
857 	/*
858 	 * Pinmux settings are in board file now, until pinmux is supported,
859 	 * we can set pinmux here in probe function.
860 	 */
861 
862 	debug("i2c : controller bus %d at %lu , speed %d: ",
863 	      bus->seq, i2c_bus->base,
864 	      i2c_bus->speed);
865 
866 	return 0;
867 }
868 
869 static int mxc_i2c_probe_chip(struct udevice *bus, u32 chip_addr,
870 			      u32 chip_flags)
871 {
872 	int ret;
873 	struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
874 
875 	ret = i2c_init_transfer(i2c_bus, chip_addr, 0, 0);
876 	if (ret < 0) {
877 		debug("%s failed, ret = %d\n", __func__, ret);
878 		return ret;
879 	}
880 
881 	i2c_imx_stop(i2c_bus);
882 
883 	return 0;
884 }
885 
886 static int mxc_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
887 {
888 	struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
889 	int ret = 0;
890 	ulong base = i2c_bus->base;
891 	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
892 		VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
893 
894 	/*
895 	 * Here the 3rd parameter addr and the 4th one alen are set to 0,
896 	 * because here we only want to send out chip address. The register
897 	 * address is wrapped in msg.
898 	 */
899 	ret = i2c_init_transfer(i2c_bus, msg->addr, 0, 0);
900 	if (ret < 0) {
901 		debug("i2c_init_transfer error: %d\n", ret);
902 		return ret;
903 	}
904 
905 	for (; nmsgs > 0; nmsgs--, msg++) {
906 		bool next_is_read = nmsgs > 1 && (msg[1].flags & I2C_M_RD);
907 		debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
908 		if (msg->flags & I2C_M_RD)
909 			ret = i2c_read_data(i2c_bus, msg->addr, msg->buf,
910 					    msg->len);
911 		else {
912 			ret = i2c_write_data(i2c_bus, msg->addr, msg->buf,
913 					     msg->len);
914 			if (ret)
915 				break;
916 			if (next_is_read) {
917 				/* Reuse ret */
918 				ret = readb(base + (I2CR << reg_shift));
919 				ret |= I2CR_RSTA;
920 				writeb(ret, base + (I2CR << reg_shift));
921 
922 				ret = tx_byte(i2c_bus, (msg->addr << 1) | 1);
923 				if (ret < 0) {
924 					i2c_imx_stop(i2c_bus);
925 					break;
926 				}
927 			}
928 		}
929 	}
930 
931 	if (ret)
932 		debug("i2c_write: error sending\n");
933 
934 	i2c_imx_stop(i2c_bus);
935 
936 	return ret;
937 }
938 
939 static const struct dm_i2c_ops mxc_i2c_ops = {
940 	.xfer		= mxc_i2c_xfer,
941 	.probe_chip	= mxc_i2c_probe_chip,
942 	.set_bus_speed	= mxc_i2c_set_bus_speed,
943 };
944 
945 static const struct udevice_id mxc_i2c_ids[] = {
946 	{ .compatible = "fsl,imx21-i2c", },
947 	{ .compatible = "fsl,vf610-i2c", .data = I2C_QUIRK_FLAG, },
948 	{}
949 };
950 
951 U_BOOT_DRIVER(i2c_mxc) = {
952 	.name = "i2c_mxc",
953 	.id = UCLASS_I2C,
954 	.of_match = mxc_i2c_ids,
955 	.probe = mxc_i2c_probe,
956 	.priv_auto_alloc_size = sizeof(struct mxc_i2c_bus),
957 	.ops = &mxc_i2c_ops,
958 };
959 #endif
960