xref: /openbmc/u-boot/drivers/i2c/s3c24x0_i2c.c (revision cb379a34)
1 /*
2  * (C) Copyright 2002
3  * David Mueller, ELSOFT AG, d.mueller@elsoft.ch
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 /* This code should work for both the S3C2400 and the S3C2410
9  * as they seem to have the same I2C controller inside.
10  * The different address mapping is handled by the s3c24xx.h files below.
11  */
12 #include <common.h>
13 #include <errno.h>
14 #include <dm.h>
15 #include <fdtdec.h>
16 #if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
17 #include <asm/arch/clk.h>
18 #include <asm/arch/cpu.h>
19 #include <asm/arch/pinmux.h>
20 #else
21 #include <asm/arch/s3c24x0_cpu.h>
22 #endif
23 #include <asm/io.h>
24 #include <i2c.h>
25 #include "s3c24x0_i2c.h"
26 
27 #define	I2C_WRITE	0
28 #define I2C_READ	1
29 
30 #define I2C_OK		0
31 #define I2C_NOK		1
32 #define I2C_NACK	2
33 #define I2C_NOK_LA	3	/* Lost arbitration */
34 #define I2C_NOK_TOUT	4	/* time out */
35 
36 /* HSI2C specific register description */
37 
38 /* I2C_CTL Register bits */
39 #define HSI2C_FUNC_MODE_I2C		(1u << 0)
40 #define HSI2C_MASTER			(1u << 3)
41 #define HSI2C_RXCHON			(1u << 6)	/* Write/Send */
42 #define HSI2C_TXCHON			(1u << 7)	/* Read/Receive */
43 #define HSI2C_SW_RST			(1u << 31)
44 
45 /* I2C_FIFO_CTL Register bits */
46 #define HSI2C_RXFIFO_EN			(1u << 0)
47 #define HSI2C_TXFIFO_EN			(1u << 1)
48 #define HSI2C_TXFIFO_TRIGGER_LEVEL	(0x20 << 16)
49 #define HSI2C_RXFIFO_TRIGGER_LEVEL	(0x20 << 4)
50 
51 /* I2C_TRAILING_CTL Register bits */
52 #define HSI2C_TRAILING_COUNT		(0xff)
53 
54 /* I2C_INT_EN Register bits */
55 #define HSI2C_TX_UNDERRUN_EN		(1u << 2)
56 #define HSI2C_TX_OVERRUN_EN		(1u << 3)
57 #define HSI2C_RX_UNDERRUN_EN		(1u << 4)
58 #define HSI2C_RX_OVERRUN_EN		(1u << 5)
59 #define HSI2C_INT_TRAILING_EN		(1u << 6)
60 #define HSI2C_INT_I2C_EN		(1u << 9)
61 
62 #define HSI2C_INT_ERROR_MASK	(HSI2C_TX_UNDERRUN_EN |\
63 				 HSI2C_TX_OVERRUN_EN  |\
64 				 HSI2C_RX_UNDERRUN_EN |\
65 				 HSI2C_RX_OVERRUN_EN  |\
66 				 HSI2C_INT_TRAILING_EN)
67 
68 /* I2C_CONF Register bits */
69 #define HSI2C_AUTO_MODE			(1u << 31)
70 #define HSI2C_10BIT_ADDR_MODE		(1u << 30)
71 #define HSI2C_HS_MODE			(1u << 29)
72 
73 /* I2C_AUTO_CONF Register bits */
74 #define HSI2C_READ_WRITE		(1u << 16)
75 #define HSI2C_STOP_AFTER_TRANS		(1u << 17)
76 #define HSI2C_MASTER_RUN		(1u << 31)
77 
78 /* I2C_TIMEOUT Register bits */
79 #define HSI2C_TIMEOUT_EN		(1u << 31)
80 
81 /* I2C_TRANS_STATUS register bits */
82 #define HSI2C_MASTER_BUSY		(1u << 17)
83 #define HSI2C_SLAVE_BUSY		(1u << 16)
84 #define HSI2C_TIMEOUT_AUTO		(1u << 4)
85 #define HSI2C_NO_DEV			(1u << 3)
86 #define HSI2C_NO_DEV_ACK		(1u << 2)
87 #define HSI2C_TRANS_ABORT		(1u << 1)
88 #define HSI2C_TRANS_SUCCESS		(1u << 0)
89 #define HSI2C_TRANS_ERROR_MASK	(HSI2C_TIMEOUT_AUTO |\
90 				 HSI2C_NO_DEV | HSI2C_NO_DEV_ACK |\
91 				 HSI2C_TRANS_ABORT)
92 #define HSI2C_TRANS_FINISHED_MASK (HSI2C_TRANS_ERROR_MASK | HSI2C_TRANS_SUCCESS)
93 
94 
95 /* I2C_FIFO_STAT Register bits */
96 #define HSI2C_RX_FIFO_EMPTY		(1u << 24)
97 #define HSI2C_RX_FIFO_FULL		(1u << 23)
98 #define HSI2C_TX_FIFO_EMPTY		(1u << 8)
99 #define HSI2C_TX_FIFO_FULL		(1u << 7)
100 #define HSI2C_RX_FIFO_LEVEL(x)		(((x) >> 16) & 0x7f)
101 #define HSI2C_TX_FIFO_LEVEL(x)		((x) & 0x7f)
102 
103 #define HSI2C_SLV_ADDR_MAS(x)		((x & 0x3ff) << 10)
104 
105 /* S3C I2C Controller bits */
106 #define I2CSTAT_BSY	0x20	/* Busy bit */
107 #define I2CSTAT_NACK	0x01	/* Nack bit */
108 #define I2CCON_ACKGEN	0x80	/* Acknowledge generation */
109 #define I2CCON_IRPND	0x10	/* Interrupt pending bit */
110 #define I2C_MODE_MT	0xC0	/* Master Transmit Mode */
111 #define I2C_MODE_MR	0x80	/* Master Receive Mode */
112 #define I2C_START_STOP	0x20	/* START / STOP */
113 #define I2C_TXRX_ENA	0x10	/* I2C Tx/Rx enable */
114 
115 #define I2C_TIMEOUT_MS 10		/* 10 ms */
116 
117 #define	HSI2C_TIMEOUT_US 10000 /* 10 ms, finer granularity */
118 
119 
120 /* To support VCMA9 boards and other who dont define max_i2c_num */
121 #ifndef CONFIG_MAX_I2C_NUM
122 #define CONFIG_MAX_I2C_NUM 1
123 #endif
124 
125 DECLARE_GLOBAL_DATA_PTR;
126 
127 /*
128  * For SPL boot some boards need i2c before SDRAM is initialised so force
129  * variables to live in SRAM
130  */
131 #ifdef CONFIG_SYS_I2C
132 static struct s3c24x0_i2c_bus i2c_bus[CONFIG_MAX_I2C_NUM]
133 			__attribute__((section(".data")));
134 #endif
135 
136 enum exynos_i2c_type {
137 	EXYNOS_I2C_STD,
138 	EXYNOS_I2C_HS,
139 };
140 
141 #ifdef CONFIG_SYS_I2C
142 /**
143  * Get a pointer to the given bus index
144  *
145  * @bus_idx: Bus index to look up
146  * @return pointer to bus, or NULL if invalid or not available
147  */
148 static struct s3c24x0_i2c_bus *get_bus(unsigned int bus_idx)
149 {
150 	if (bus_idx < ARRAY_SIZE(i2c_bus)) {
151 		struct s3c24x0_i2c_bus *bus;
152 
153 		bus = &i2c_bus[bus_idx];
154 		if (bus->active)
155 			return bus;
156 	}
157 
158 	debug("Undefined bus: %d\n", bus_idx);
159 	return NULL;
160 }
161 #endif
162 
163 #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
164 static int GetI2CSDA(void)
165 {
166 	struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio();
167 
168 #if defined(CONFIG_S3C2410) || defined(CONFIG_S3C2440)
169 	return (readl(&gpio->gpedat) & 0x8000) >> 15;
170 #endif
171 #ifdef CONFIG_S3C2400
172 	return (readl(&gpio->pgdat) & 0x0020) >> 5;
173 #endif
174 }
175 
176 static void SetI2CSCL(int x)
177 {
178 	struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio();
179 
180 #if defined(CONFIG_S3C2410) || defined(CONFIG_S3C2440)
181 	writel((readl(&gpio->gpedat) & ~0x4000) |
182 					(x & 1) << 14, &gpio->gpedat);
183 #endif
184 #ifdef CONFIG_S3C2400
185 	writel((readl(&gpio->pgdat) & ~0x0040) | (x & 1) << 6, &gpio->pgdat);
186 #endif
187 }
188 #endif
189 
190 /*
191  * Wait til the byte transfer is completed.
192  *
193  * @param i2c- pointer to the appropriate i2c register bank.
194  * @return I2C_OK, if transmission was ACKED
195  *         I2C_NACK, if transmission was NACKED
196  *         I2C_NOK_TIMEOUT, if transaction did not complete in I2C_TIMEOUT_MS
197  */
198 
199 static int WaitForXfer(struct s3c24x0_i2c *i2c)
200 {
201 	ulong start_time = get_timer(0);
202 
203 	do {
204 		if (readl(&i2c->iiccon) & I2CCON_IRPND)
205 			return (readl(&i2c->iicstat) & I2CSTAT_NACK) ?
206 				I2C_NACK : I2C_OK;
207 	} while (get_timer(start_time) < I2C_TIMEOUT_MS);
208 
209 	return I2C_NOK_TOUT;
210 }
211 
212 /*
213  * Wait for transfer completion.
214  *
215  * This function reads the interrupt status register waiting for the INT_I2C
216  * bit to be set, which indicates copletion of a transaction.
217  *
218  * @param i2c: pointer to the appropriate register bank
219  *
220  * @return: I2C_OK in case of successful completion, I2C_NOK_TIMEOUT in case
221  *          the status bits do not get set in time, or an approrpiate error
222  *          value in case of transfer errors.
223  */
224 static int hsi2c_wait_for_trx(struct exynos5_hsi2c *i2c)
225 {
226 	int i = HSI2C_TIMEOUT_US;
227 
228 	while (i-- > 0) {
229 		u32 int_status = readl(&i2c->usi_int_stat);
230 
231 		if (int_status & HSI2C_INT_I2C_EN) {
232 			u32 trans_status = readl(&i2c->usi_trans_status);
233 
234 			/* Deassert pending interrupt. */
235 			writel(int_status, &i2c->usi_int_stat);
236 
237 			if (trans_status & HSI2C_NO_DEV_ACK) {
238 				debug("%s: no ACK from device\n", __func__);
239 				return I2C_NACK;
240 			}
241 			if (trans_status & HSI2C_NO_DEV) {
242 				debug("%s: no device\n", __func__);
243 				return I2C_NOK;
244 			}
245 			if (trans_status & HSI2C_TRANS_ABORT) {
246 				debug("%s: arbitration lost\n", __func__);
247 				return I2C_NOK_LA;
248 			}
249 			if (trans_status & HSI2C_TIMEOUT_AUTO) {
250 				debug("%s: device timed out\n", __func__);
251 				return I2C_NOK_TOUT;
252 			}
253 			return I2C_OK;
254 		}
255 		udelay(1);
256 	}
257 	debug("%s: transaction timeout!\n", __func__);
258 	return I2C_NOK_TOUT;
259 }
260 
261 static void read_write_byte(struct s3c24x0_i2c *i2c)
262 {
263 	clrbits_le32(&i2c->iiccon, I2CCON_IRPND);
264 }
265 
266 #ifdef CONFIG_SYS_I2C
267 static struct s3c24x0_i2c *get_base_i2c(int bus)
268 {
269 #ifdef CONFIG_EXYNOS4
270 	struct s3c24x0_i2c *i2c = (struct s3c24x0_i2c *)(samsung_get_base_i2c()
271 							+ (EXYNOS4_I2C_SPACING
272 							* bus));
273 	return i2c;
274 #elif defined CONFIG_EXYNOS5
275 	struct s3c24x0_i2c *i2c = (struct s3c24x0_i2c *)(samsung_get_base_i2c()
276 							+ (EXYNOS5_I2C_SPACING
277 							* bus));
278 	return i2c;
279 #else
280 	return s3c24x0_get_base_i2c();
281 #endif
282 }
283 #endif
284 
285 static void i2c_ch_init(struct s3c24x0_i2c *i2c, int speed, int slaveadd)
286 {
287 	ulong freq, pres = 16, div;
288 #if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
289 	freq = get_i2c_clk();
290 #else
291 	freq = get_PCLK();
292 #endif
293 	/* calculate prescaler and divisor values */
294 	if ((freq / pres / (16 + 1)) > speed)
295 		/* set prescaler to 512 */
296 		pres = 512;
297 
298 	div = 0;
299 	while ((freq / pres / (div + 1)) > speed)
300 		div++;
301 
302 	/* set prescaler, divisor according to freq, also set ACKGEN, IRQ */
303 	writel((div & 0x0F) | 0xA0 | ((pres == 512) ? 0x40 : 0), &i2c->iiccon);
304 
305 	/* init to SLAVE REVEIVE and set slaveaddr */
306 	writel(0, &i2c->iicstat);
307 	writel(slaveadd, &i2c->iicadd);
308 	/* program Master Transmit (and implicit STOP) */
309 	writel(I2C_MODE_MT | I2C_TXRX_ENA, &i2c->iicstat);
310 }
311 
312 static int hsi2c_get_clk_details(struct s3c24x0_i2c_bus *i2c_bus)
313 {
314 	struct exynos5_hsi2c *hsregs = i2c_bus->hsregs;
315 	ulong clkin;
316 	unsigned int op_clk = i2c_bus->clock_frequency;
317 	unsigned int i = 0, utemp0 = 0, utemp1 = 0;
318 	unsigned int t_ftl_cycle;
319 
320 #if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
321 	clkin = get_i2c_clk();
322 #else
323 	clkin = get_PCLK();
324 #endif
325 	/* FPCLK / FI2C =
326 	 * (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) + 8 + 2 * FLT_CYCLE
327 	 * uTemp0 = (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2)
328 	 * uTemp1 = (TSCLK_L + TSCLK_H + 2)
329 	 * uTemp2 = TSCLK_L + TSCLK_H
330 	 */
331 	t_ftl_cycle = (readl(&hsregs->usi_conf) >> 16) & 0x7;
332 	utemp0 = (clkin / op_clk) - 8 - 2 * t_ftl_cycle;
333 
334 	/* CLK_DIV max is 256 */
335 	for (i = 0; i < 256; i++) {
336 		utemp1 = utemp0 / (i + 1);
337 		if ((utemp1 < 512) && (utemp1 > 4)) {
338 			i2c_bus->clk_cycle = utemp1 - 2;
339 			i2c_bus->clk_div = i;
340 			return 0;
341 		}
342 	}
343 	return -EINVAL;
344 }
345 
346 static void hsi2c_ch_init(struct s3c24x0_i2c_bus *i2c_bus)
347 {
348 	struct exynos5_hsi2c *hsregs = i2c_bus->hsregs;
349 	unsigned int t_sr_release;
350 	unsigned int n_clkdiv;
351 	unsigned int t_start_su, t_start_hd;
352 	unsigned int t_stop_su;
353 	unsigned int t_data_su, t_data_hd;
354 	unsigned int t_scl_l, t_scl_h;
355 	u32 i2c_timing_s1;
356 	u32 i2c_timing_s2;
357 	u32 i2c_timing_s3;
358 	u32 i2c_timing_sla;
359 
360 	n_clkdiv = i2c_bus->clk_div;
361 	t_scl_l = i2c_bus->clk_cycle / 2;
362 	t_scl_h = i2c_bus->clk_cycle / 2;
363 	t_start_su = t_scl_l;
364 	t_start_hd = t_scl_l;
365 	t_stop_su = t_scl_l;
366 	t_data_su = t_scl_l / 2;
367 	t_data_hd = t_scl_l / 2;
368 	t_sr_release = i2c_bus->clk_cycle;
369 
370 	i2c_timing_s1 = t_start_su << 24 | t_start_hd << 16 | t_stop_su << 8;
371 	i2c_timing_s2 = t_data_su << 24 | t_scl_l << 8 | t_scl_h << 0;
372 	i2c_timing_s3 = n_clkdiv << 16 | t_sr_release << 0;
373 	i2c_timing_sla = t_data_hd << 0;
374 
375 	writel(HSI2C_TRAILING_COUNT, &hsregs->usi_trailing_ctl);
376 
377 	/* Clear to enable Timeout */
378 	clrsetbits_le32(&hsregs->usi_timeout, HSI2C_TIMEOUT_EN, 0);
379 
380 	/* set AUTO mode */
381 	writel(readl(&hsregs->usi_conf) | HSI2C_AUTO_MODE, &hsregs->usi_conf);
382 
383 	/* Enable completion conditions' reporting. */
384 	writel(HSI2C_INT_I2C_EN, &hsregs->usi_int_en);
385 
386 	/* Enable FIFOs */
387 	writel(HSI2C_RXFIFO_EN | HSI2C_TXFIFO_EN, &hsregs->usi_fifo_ctl);
388 
389 	/* Currently operating in Fast speed mode. */
390 	writel(i2c_timing_s1, &hsregs->usi_timing_fs1);
391 	writel(i2c_timing_s2, &hsregs->usi_timing_fs2);
392 	writel(i2c_timing_s3, &hsregs->usi_timing_fs3);
393 	writel(i2c_timing_sla, &hsregs->usi_timing_sla);
394 }
395 
396 /* SW reset for the high speed bus */
397 static void exynos5_i2c_reset(struct s3c24x0_i2c_bus *i2c_bus)
398 {
399 	struct exynos5_hsi2c *i2c = i2c_bus->hsregs;
400 	u32 i2c_ctl;
401 
402 	/* Set and clear the bit for reset */
403 	i2c_ctl = readl(&i2c->usi_ctl);
404 	i2c_ctl |= HSI2C_SW_RST;
405 	writel(i2c_ctl, &i2c->usi_ctl);
406 
407 	i2c_ctl = readl(&i2c->usi_ctl);
408 	i2c_ctl &= ~HSI2C_SW_RST;
409 	writel(i2c_ctl, &i2c->usi_ctl);
410 
411 	/* Initialize the configure registers */
412 	hsi2c_ch_init(i2c_bus);
413 }
414 
415 #ifdef CONFIG_SYS_I2C
416 static void s3c24x0_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
417 {
418 	struct s3c24x0_i2c *i2c;
419 	struct s3c24x0_i2c_bus *bus;
420 #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
421 	struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio();
422 #endif
423 	ulong start_time = get_timer(0);
424 
425 	i2c = get_base_i2c(adap->hwadapnr);
426 	bus = &i2c_bus[adap->hwadapnr];
427 	if (!bus)
428 		return;
429 
430 	/*
431 	 * In case the previous transfer is still going, wait to give it a
432 	 * chance to finish.
433 	 */
434 	while (readl(&i2c->iicstat) & I2CSTAT_BSY) {
435 		if (get_timer(start_time) > I2C_TIMEOUT_MS) {
436 			printf("%s: I2C bus busy for %p\n", __func__,
437 			       &i2c->iicstat);
438 			return;
439 		}
440 	}
441 
442 #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
443 	int i;
444 
445 	if ((readl(&i2c->iicstat) & I2CSTAT_BSY) || GetI2CSDA() == 0) {
446 #if defined(CONFIG_S3C2410) || defined(CONFIG_S3C2440)
447 		ulong old_gpecon = readl(&gpio->gpecon);
448 #endif
449 #ifdef CONFIG_S3C2400
450 		ulong old_gpecon = readl(&gpio->pgcon);
451 #endif
452 		/* bus still busy probably by (most) previously interrupted
453 		   transfer */
454 
455 #if defined(CONFIG_S3C2410) || defined(CONFIG_S3C2440)
456 		/* set I2CSDA and I2CSCL (GPE15, GPE14) to GPIO */
457 		writel((readl(&gpio->gpecon) & ~0xF0000000) | 0x10000000,
458 		       &gpio->gpecon);
459 #endif
460 #ifdef CONFIG_S3C2400
461 		/* set I2CSDA and I2CSCL (PG5, PG6) to GPIO */
462 		writel((readl(&gpio->pgcon) & ~0x00003c00) | 0x00001000,
463 		       &gpio->pgcon);
464 #endif
465 
466 		/* toggle I2CSCL until bus idle */
467 		SetI2CSCL(0);
468 		udelay(1000);
469 		i = 10;
470 		while ((i > 0) && (GetI2CSDA() != 1)) {
471 			SetI2CSCL(1);
472 			udelay(1000);
473 			SetI2CSCL(0);
474 			udelay(1000);
475 			i--;
476 		}
477 		SetI2CSCL(1);
478 		udelay(1000);
479 
480 		/* restore pin functions */
481 #if defined(CONFIG_S3C2410) || defined(CONFIG_S3C2440)
482 		writel(old_gpecon, &gpio->gpecon);
483 #endif
484 #ifdef CONFIG_S3C2400
485 		writel(old_gpecon, &gpio->pgcon);
486 #endif
487 	}
488 #endif /* #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) */
489 
490 	i2c_ch_init(i2c, speed, slaveadd);
491 
492 	bus->active = true;
493 	bus->regs = i2c;
494 }
495 #endif /* CONFIG_SYS_I2C */
496 
497 /*
498  * Poll the appropriate bit of the fifo status register until the interface is
499  * ready to process the next byte or timeout expires.
500  *
501  * In addition to the FIFO status register this function also polls the
502  * interrupt status register to be able to detect unexpected transaction
503  * completion.
504  *
505  * When FIFO is ready to process the next byte, this function returns I2C_OK.
506  * If in course of polling the INT_I2C assertion is detected, the function
507  * returns I2C_NOK. If timeout happens before any of the above conditions is
508  * met - the function returns I2C_NOK_TOUT;
509 
510  * @param i2c: pointer to the appropriate i2c register bank.
511  * @param rx_transfer: set to True if the receive transaction is in progress.
512  * @return: as described above.
513  */
514 static unsigned hsi2c_poll_fifo(struct exynos5_hsi2c *i2c, bool rx_transfer)
515 {
516 	u32 fifo_bit = rx_transfer ? HSI2C_RX_FIFO_EMPTY : HSI2C_TX_FIFO_FULL;
517 	int i = HSI2C_TIMEOUT_US;
518 
519 	while (readl(&i2c->usi_fifo_stat) & fifo_bit) {
520 		if (readl(&i2c->usi_int_stat) & HSI2C_INT_I2C_EN) {
521 			/*
522 			 * There is a chance that assertion of
523 			 * HSI2C_INT_I2C_EN and deassertion of
524 			 * HSI2C_RX_FIFO_EMPTY happen simultaneously. Let's
525 			 * give FIFO status priority and check it one more
526 			 * time before reporting interrupt. The interrupt will
527 			 * be reported next time this function is called.
528 			 */
529 			if (rx_transfer &&
530 			    !(readl(&i2c->usi_fifo_stat) & fifo_bit))
531 				break;
532 			return I2C_NOK;
533 		}
534 		if (!i--) {
535 			debug("%s: FIFO polling timeout!\n", __func__);
536 			return I2C_NOK_TOUT;
537 		}
538 		udelay(1);
539 	}
540 	return I2C_OK;
541 }
542 
543 /*
544  * Preapre hsi2c transaction, either read or write.
545  *
546  * Set up transfer as described in section 27.5.1.2 'I2C Channel Auto Mode' of
547  * the 5420 UM.
548  *
549  * @param i2c: pointer to the appropriate i2c register bank.
550  * @param chip: slave address on the i2c bus (with read/write bit exlcuded)
551  * @param len: number of bytes expected to be sent or received
552  * @param rx_transfer: set to true for receive transactions
553  * @param: issue_stop: set to true if i2c stop condition should be generated
554  *         after this transaction.
555  * @return: I2C_NOK_TOUT in case the bus remained busy for HSI2C_TIMEOUT_US,
556  *          I2C_OK otherwise.
557  */
558 static int hsi2c_prepare_transaction(struct exynos5_hsi2c *i2c,
559 				     u8 chip,
560 				     u16 len,
561 				     bool rx_transfer,
562 				     bool issue_stop)
563 {
564 	u32 conf;
565 
566 	conf = len | HSI2C_MASTER_RUN;
567 
568 	if (issue_stop)
569 		conf |= HSI2C_STOP_AFTER_TRANS;
570 
571 	/* Clear to enable Timeout */
572 	writel(readl(&i2c->usi_timeout) & ~HSI2C_TIMEOUT_EN, &i2c->usi_timeout);
573 
574 	/* Set slave address */
575 	writel(HSI2C_SLV_ADDR_MAS(chip), &i2c->i2c_addr);
576 
577 	if (rx_transfer) {
578 		/* i2c master, read transaction */
579 		writel((HSI2C_RXCHON | HSI2C_FUNC_MODE_I2C | HSI2C_MASTER),
580 		       &i2c->usi_ctl);
581 
582 		/* read up to len bytes, stop after transaction is finished */
583 		writel(conf | HSI2C_READ_WRITE, &i2c->usi_auto_conf);
584 	} else {
585 		/* i2c master, write transaction */
586 		writel((HSI2C_TXCHON | HSI2C_FUNC_MODE_I2C | HSI2C_MASTER),
587 		       &i2c->usi_ctl);
588 
589 		/* write up to len bytes, stop after transaction is finished */
590 		writel(conf, &i2c->usi_auto_conf);
591 	}
592 
593 	/* Reset all pending interrupt status bits we care about, if any */
594 	writel(HSI2C_INT_I2C_EN, &i2c->usi_int_stat);
595 
596 	return I2C_OK;
597 }
598 
599 /*
600  * Wait while i2c bus is settling down (mostly stop gets completed).
601  */
602 static int hsi2c_wait_while_busy(struct exynos5_hsi2c *i2c)
603 {
604 	int i = HSI2C_TIMEOUT_US;
605 
606 	while (readl(&i2c->usi_trans_status) & HSI2C_MASTER_BUSY) {
607 		if (!i--) {
608 			debug("%s: bus busy\n", __func__);
609 			return I2C_NOK_TOUT;
610 		}
611 		udelay(1);
612 	}
613 	return I2C_OK;
614 }
615 
616 static int hsi2c_write(struct exynos5_hsi2c *i2c,
617 		       unsigned char chip,
618 		       unsigned char addr[],
619 		       unsigned char alen,
620 		       unsigned char data[],
621 		       unsigned short len,
622 		       bool issue_stop)
623 {
624 	int i, rv = 0;
625 
626 	if (!(len + alen)) {
627 		/* Writes of zero length not supported in auto mode. */
628 		debug("%s: zero length writes not supported\n", __func__);
629 		return I2C_NOK;
630 	}
631 
632 	rv = hsi2c_prepare_transaction
633 		(i2c, chip, len + alen, false, issue_stop);
634 	if (rv != I2C_OK)
635 		return rv;
636 
637 	/* Move address, if any, and the data, if any, into the FIFO. */
638 	for (i = 0; i < alen; i++) {
639 		rv = hsi2c_poll_fifo(i2c, false);
640 		if (rv != I2C_OK) {
641 			debug("%s: address write failed\n", __func__);
642 			goto write_error;
643 		}
644 		writel(addr[i], &i2c->usi_txdata);
645 	}
646 
647 	for (i = 0; i < len; i++) {
648 		rv = hsi2c_poll_fifo(i2c, false);
649 		if (rv != I2C_OK) {
650 			debug("%s: data write failed\n", __func__);
651 			goto write_error;
652 		}
653 		writel(data[i], &i2c->usi_txdata);
654 	}
655 
656 	rv = hsi2c_wait_for_trx(i2c);
657 
658  write_error:
659 	if (issue_stop) {
660 		int tmp_ret = hsi2c_wait_while_busy(i2c);
661 		if (rv == I2C_OK)
662 			rv = tmp_ret;
663 	}
664 
665 	writel(HSI2C_FUNC_MODE_I2C, &i2c->usi_ctl); /* done */
666 	return rv;
667 }
668 
669 static int hsi2c_read(struct exynos5_hsi2c *i2c,
670 		      unsigned char chip,
671 		      unsigned char addr[],
672 		      unsigned char alen,
673 		      unsigned char data[],
674 		      unsigned short len)
675 {
676 	int i, rv, tmp_ret;
677 	bool drop_data = false;
678 
679 	if (!len) {
680 		/* Reads of zero length not supported in auto mode. */
681 		debug("%s: zero length read adjusted\n", __func__);
682 		drop_data = true;
683 		len = 1;
684 	}
685 
686 	if (alen) {
687 		/* Internal register adress needs to be written first. */
688 		rv = hsi2c_write(i2c, chip, addr, alen, NULL, 0, false);
689 		if (rv != I2C_OK)
690 			return rv;
691 	}
692 
693 	rv = hsi2c_prepare_transaction(i2c, chip, len, true, true);
694 
695 	if (rv != I2C_OK)
696 		return rv;
697 
698 	for (i = 0; i < len; i++) {
699 		rv = hsi2c_poll_fifo(i2c, true);
700 		if (rv != I2C_OK)
701 			goto read_err;
702 		if (drop_data)
703 			continue;
704 		data[i] = readl(&i2c->usi_rxdata);
705 	}
706 
707 	rv = hsi2c_wait_for_trx(i2c);
708 
709  read_err:
710 	tmp_ret = hsi2c_wait_while_busy(i2c);
711 	if (rv == I2C_OK)
712 		rv = tmp_ret;
713 
714 	writel(HSI2C_FUNC_MODE_I2C, &i2c->usi_ctl); /* done */
715 	return rv;
716 }
717 
718 #ifdef CONFIG_SYS_I2C
719 static unsigned int s3c24x0_i2c_set_bus_speed(struct i2c_adapter *adap,
720 					      unsigned int speed)
721 #else
722 static int s3c24x0_i2c_set_bus_speed(struct udevice *dev, unsigned int speed)
723 #endif
724 {
725 	struct s3c24x0_i2c_bus *i2c_bus;
726 
727 #ifdef CONFIG_SYS_I2C
728 	i2c_bus = get_bus(adap->hwadapnr);
729 	if (!i2c_bus)
730 		return -EFAULT;
731 #else
732 	i2c_bus = dev_get_priv(dev);
733 #endif
734 	i2c_bus->clock_frequency = speed;
735 
736 	if (i2c_bus->is_highspeed) {
737 		if (hsi2c_get_clk_details(i2c_bus))
738 			return -EFAULT;
739 		hsi2c_ch_init(i2c_bus);
740 	} else {
741 		i2c_ch_init(i2c_bus->regs, i2c_bus->clock_frequency,
742 			    CONFIG_SYS_I2C_S3C24X0_SLAVE);
743 	}
744 
745 	return 0;
746 }
747 
748 /*
749  * cmd_type is 0 for write, 1 for read.
750  *
751  * addr_len can take any value from 0-255, it is only limited
752  * by the char, we could make it larger if needed. If it is
753  * 0 we skip the address write cycle.
754  */
755 static int i2c_transfer(struct s3c24x0_i2c *i2c,
756 			unsigned char cmd_type,
757 			unsigned char chip,
758 			unsigned char addr[],
759 			unsigned char addr_len,
760 			unsigned char data[],
761 			unsigned short data_len)
762 {
763 	int i = 0, result;
764 	ulong start_time = get_timer(0);
765 
766 	if (data == 0 || data_len == 0) {
767 		/*Don't support data transfer of no length or to address 0 */
768 		debug("i2c_transfer: bad call\n");
769 		return I2C_NOK;
770 	}
771 
772 	while (readl(&i2c->iicstat) & I2CSTAT_BSY) {
773 		if (get_timer(start_time) > I2C_TIMEOUT_MS)
774 			return I2C_NOK_TOUT;
775 	}
776 
777 	writel(readl(&i2c->iiccon) | I2CCON_ACKGEN, &i2c->iiccon);
778 
779 	/* Get the slave chip address going */
780 	writel(chip, &i2c->iicds);
781 	if ((cmd_type == I2C_WRITE) || (addr && addr_len))
782 		writel(I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP,
783 		       &i2c->iicstat);
784 	else
785 		writel(I2C_MODE_MR | I2C_TXRX_ENA | I2C_START_STOP,
786 		       &i2c->iicstat);
787 
788 	/* Wait for chip address to transmit. */
789 	result = WaitForXfer(i2c);
790 	if (result != I2C_OK)
791 		goto bailout;
792 
793 	/* If register address needs to be transmitted - do it now. */
794 	if (addr && addr_len) {
795 		while ((i < addr_len) && (result == I2C_OK)) {
796 			writel(addr[i++], &i2c->iicds);
797 			read_write_byte(i2c);
798 			result = WaitForXfer(i2c);
799 		}
800 		i = 0;
801 		if (result != I2C_OK)
802 			goto bailout;
803 	}
804 
805 	switch (cmd_type) {
806 	case I2C_WRITE:
807 		while ((i < data_len) && (result == I2C_OK)) {
808 			writel(data[i++], &i2c->iicds);
809 			read_write_byte(i2c);
810 			result = WaitForXfer(i2c);
811 		}
812 		break;
813 
814 	case I2C_READ:
815 		if (addr && addr_len) {
816 			/*
817 			 * Register address has been sent, now send slave chip
818 			 * address again to start the actual read transaction.
819 			 */
820 			writel(chip, &i2c->iicds);
821 
822 			/* Generate a re-START. */
823 			writel(I2C_MODE_MR | I2C_TXRX_ENA | I2C_START_STOP,
824 				&i2c->iicstat);
825 			read_write_byte(i2c);
826 			result = WaitForXfer(i2c);
827 
828 			if (result != I2C_OK)
829 				goto bailout;
830 		}
831 
832 		while ((i < data_len) && (result == I2C_OK)) {
833 			/* disable ACK for final READ */
834 			if (i == data_len - 1)
835 				writel(readl(&i2c->iiccon)
836 				       & ~I2CCON_ACKGEN,
837 				       &i2c->iiccon);
838 			read_write_byte(i2c);
839 			result = WaitForXfer(i2c);
840 			data[i++] = readl(&i2c->iicds);
841 		}
842 		if (result == I2C_NACK)
843 			result = I2C_OK; /* Normal terminated read. */
844 		break;
845 
846 	default:
847 		debug("i2c_transfer: bad call\n");
848 		result = I2C_NOK;
849 		break;
850 	}
851 
852 bailout:
853 	/* Send STOP. */
854 	writel(I2C_MODE_MR | I2C_TXRX_ENA, &i2c->iicstat);
855 	read_write_byte(i2c);
856 
857 	return result;
858 }
859 
860 #ifdef CONFIG_SYS_I2C
861 static int s3c24x0_i2c_probe(struct i2c_adapter *adap, uchar chip)
862 #else
863 static int s3c24x0_i2c_probe(struct udevice *dev, uint chip, uint chip_flags)
864 #endif
865 {
866 	struct s3c24x0_i2c_bus *i2c_bus;
867 	uchar buf[1];
868 	int ret;
869 
870 #ifdef CONFIG_SYS_I2C
871 	i2c_bus = get_bus(adap->hwadapnr);
872 	if (!i2c_bus)
873 		return -EFAULT;
874 #else
875 	i2c_bus = dev_get_priv(dev);
876 #endif
877 	buf[0] = 0;
878 
879 	/*
880 	 * What is needed is to send the chip address and verify that the
881 	 * address was <ACK>ed (i.e. there was a chip at that address which
882 	 * drove the data line low).
883 	 */
884 	if (i2c_bus->is_highspeed) {
885 		ret = hsi2c_read(i2c_bus->hsregs,
886 				chip, 0, 0, buf, 1);
887 	} else {
888 		ret = i2c_transfer(i2c_bus->regs,
889 				I2C_READ, chip << 1, 0, 0, buf, 1);
890 	}
891 
892 	return ret != I2C_OK;
893 }
894 
895 #ifdef CONFIG_SYS_I2C
896 static int s3c24x0_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
897 			    int alen, uchar *buffer, int len)
898 {
899 	struct s3c24x0_i2c_bus *i2c_bus;
900 	uchar xaddr[4];
901 	int ret;
902 
903 	i2c_bus = get_bus(adap->hwadapnr);
904 	if (!i2c_bus)
905 		return -EFAULT;
906 
907 	if (alen > 4) {
908 		debug("I2C read: addr len %d not supported\n", alen);
909 		return -EADDRNOTAVAIL;
910 	}
911 
912 	if (alen > 0) {
913 		xaddr[0] = (addr >> 24) & 0xFF;
914 		xaddr[1] = (addr >> 16) & 0xFF;
915 		xaddr[2] = (addr >> 8) & 0xFF;
916 		xaddr[3] = addr & 0xFF;
917 	}
918 
919 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
920 	/*
921 	 * EEPROM chips that implement "address overflow" are ones
922 	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
923 	 * address and the extra bits end up in the "chip address"
924 	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like
925 	 * four 256 byte chips.
926 	 *
927 	 * Note that we consider the length of the address field to
928 	 * still be one byte because the extra address bits are
929 	 * hidden in the chip address.
930 	 */
931 	if (alen > 0)
932 		chip |= ((addr >> (alen * 8)) &
933 			 CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
934 #endif
935 	if (i2c_bus->is_highspeed)
936 		ret = hsi2c_read(i2c_bus->hsregs, chip, &xaddr[4 - alen],
937 				 alen, buffer, len);
938 	else
939 		ret = i2c_transfer(i2c_bus->regs, I2C_READ, chip << 1,
940 				&xaddr[4 - alen], alen, buffer, len);
941 
942 	if (ret) {
943 		if (i2c_bus->is_highspeed)
944 			exynos5_i2c_reset(i2c_bus);
945 		debug("I2c read failed %d\n", ret);
946 		return -EIO;
947 	}
948 	return 0;
949 }
950 
951 static int s3c24x0_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
952 			 int alen, uchar *buffer, int len)
953 {
954 	struct s3c24x0_i2c_bus *i2c_bus;
955 	uchar xaddr[4];
956 	int ret;
957 
958 	i2c_bus = get_bus(adap->hwadapnr);
959 	if (!i2c_bus)
960 		return -EFAULT;
961 
962 	if (alen > 4) {
963 		debug("I2C write: addr len %d not supported\n", alen);
964 		return -EINVAL;
965 	}
966 
967 	if (alen > 0) {
968 		xaddr[0] = (addr >> 24) & 0xFF;
969 		xaddr[1] = (addr >> 16) & 0xFF;
970 		xaddr[2] = (addr >> 8) & 0xFF;
971 		xaddr[3] = addr & 0xFF;
972 	}
973 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
974 	/*
975 	 * EEPROM chips that implement "address overflow" are ones
976 	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
977 	 * address and the extra bits end up in the "chip address"
978 	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like
979 	 * four 256 byte chips.
980 	 *
981 	 * Note that we consider the length of the address field to
982 	 * still be one byte because the extra address bits are
983 	 * hidden in the chip address.
984 	 */
985 	if (alen > 0)
986 		chip |= ((addr >> (alen * 8)) &
987 			 CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
988 #endif
989 	if (i2c_bus->is_highspeed)
990 		ret = hsi2c_write(i2c_bus->hsregs, chip, &xaddr[4 - alen],
991 				  alen, buffer, len, true);
992 	else
993 		ret = i2c_transfer(i2c_bus->regs, I2C_WRITE, chip << 1,
994 				&xaddr[4 - alen], alen, buffer, len);
995 
996 	if (ret != 0) {
997 		if (i2c_bus->is_highspeed)
998 			exynos5_i2c_reset(i2c_bus);
999 		return 1;
1000 	} else {
1001 		return 0;
1002 	}
1003 }
1004 
1005 #if CONFIG_IS_ENABLED(OF_CONTROL)
1006 static void process_nodes(const void *blob, int node_list[], int count,
1007 			 int is_highspeed)
1008 {
1009 	struct s3c24x0_i2c_bus *bus;
1010 	int i, flags;
1011 
1012 	for (i = 0; i < count; i++) {
1013 		int node = node_list[i];
1014 
1015 		if (node <= 0)
1016 			continue;
1017 
1018 		bus = &i2c_bus[i];
1019 		bus->active = true;
1020 		bus->is_highspeed = is_highspeed;
1021 
1022 		if (is_highspeed) {
1023 			flags = PINMUX_FLAG_HS_MODE;
1024 			bus->hsregs = (struct exynos5_hsi2c *)
1025 					fdtdec_get_addr(blob, node, "reg");
1026 		} else {
1027 			flags = 0;
1028 			bus->regs = (struct s3c24x0_i2c *)
1029 					fdtdec_get_addr(blob, node, "reg");
1030 		}
1031 
1032 		bus->id = pinmux_decode_periph_id(blob, node);
1033 		bus->clock_frequency = fdtdec_get_int(blob, node,
1034 						"clock-frequency",
1035 						CONFIG_SYS_I2C_S3C24X0_SPEED);
1036 		bus->node = node;
1037 		bus->bus_num = i;
1038 		exynos_pinmux_config(bus->id, flags);
1039 
1040 		/* Mark position as used */
1041 		node_list[i] = -1;
1042 	}
1043 }
1044 
1045 void board_i2c_init(const void *blob)
1046 {
1047 	int node_list[CONFIG_MAX_I2C_NUM];
1048 	int count;
1049 
1050 	/* First get the normal i2c ports */
1051 	count = fdtdec_find_aliases_for_id(blob, "i2c",
1052 		COMPAT_SAMSUNG_S3C2440_I2C, node_list,
1053 		CONFIG_MAX_I2C_NUM);
1054 	process_nodes(blob, node_list, count, 0);
1055 
1056 	/* Now look for high speed i2c ports */
1057 	count = fdtdec_find_aliases_for_id(blob, "i2c",
1058 		COMPAT_SAMSUNG_EXYNOS5_I2C, node_list,
1059 		CONFIG_MAX_I2C_NUM);
1060 	process_nodes(blob, node_list, count, 1);
1061 }
1062 
1063 int i2c_get_bus_num_fdt(int node)
1064 {
1065 	int i;
1066 
1067 	for (i = 0; i < ARRAY_SIZE(i2c_bus); i++) {
1068 		if (node == i2c_bus[i].node)
1069 			return i;
1070 	}
1071 
1072 	debug("%s: Can't find any matched I2C bus\n", __func__);
1073 	return -EINVAL;
1074 }
1075 
1076 int i2c_reset_port_fdt(const void *blob, int node)
1077 {
1078 	struct s3c24x0_i2c_bus *i2c_bus;
1079 	int bus;
1080 
1081 	bus = i2c_get_bus_num_fdt(node);
1082 	if (bus < 0) {
1083 		debug("could not get bus for node %d\n", node);
1084 		return bus;
1085 	}
1086 
1087 	i2c_bus = get_bus(bus);
1088 	if (!i2c_bus) {
1089 		debug("get_bus() failed for node %d\n", node);
1090 		return -EFAULT;
1091 	}
1092 
1093 	if (i2c_bus->is_highspeed) {
1094 		if (hsi2c_get_clk_details(i2c_bus))
1095 			return -EINVAL;
1096 		hsi2c_ch_init(i2c_bus);
1097 	} else {
1098 		i2c_ch_init(i2c_bus->regs, i2c_bus->clock_frequency,
1099 			    CONFIG_SYS_I2C_S3C24X0_SLAVE);
1100 	}
1101 
1102 	return 0;
1103 }
1104 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
1105 
1106 #ifdef CONFIG_EXYNOS5
1107 static void exynos_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
1108 {
1109 	/* This will override the speed selected in the fdt for that port */
1110 	debug("i2c_init(speed=%u, slaveaddr=0x%x)\n", speed, slaveaddr);
1111 	if (i2c_set_bus_speed(speed))
1112 		error("i2c_init: failed to init bus for speed = %d", speed);
1113 }
1114 #endif /* CONFIG_EXYNOS5 */
1115 
1116 /*
1117  * Register s3c24x0 i2c adapters
1118  */
1119 #if defined(CONFIG_EXYNOS5420)
1120 U_BOOT_I2C_ADAP_COMPLETE(i2c00, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1121 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1122 			s3c24x0_i2c_set_bus_speed,
1123 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1124 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 0)
1125 U_BOOT_I2C_ADAP_COMPLETE(i2c01, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1126 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1127 			s3c24x0_i2c_set_bus_speed,
1128 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1129 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 1)
1130 U_BOOT_I2C_ADAP_COMPLETE(i2c02, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1131 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1132 			s3c24x0_i2c_set_bus_speed,
1133 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1134 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 2)
1135 U_BOOT_I2C_ADAP_COMPLETE(i2c03, exynos_i2c_init, s3c24x0_i2c_probe,
1136 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1137 			s3c24x0_i2c_set_bus_speed,
1138 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1139 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 3)
1140 U_BOOT_I2C_ADAP_COMPLETE(i2c04, exynos_i2c_init, s3c24x0_i2c_probe,
1141 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1142 			s3c24x0_i2c_set_bus_speed,
1143 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1144 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 4)
1145 U_BOOT_I2C_ADAP_COMPLETE(i2c05, exynos_i2c_init, s3c24x0_i2c_probe,
1146 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1147 			s3c24x0_i2c_set_bus_speed,
1148 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1149 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 5)
1150 U_BOOT_I2C_ADAP_COMPLETE(i2c06, exynos_i2c_init, s3c24x0_i2c_probe,
1151 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1152 			s3c24x0_i2c_set_bus_speed,
1153 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1154 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 6)
1155 U_BOOT_I2C_ADAP_COMPLETE(i2c07, exynos_i2c_init, s3c24x0_i2c_probe,
1156 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1157 			s3c24x0_i2c_set_bus_speed,
1158 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1159 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 7)
1160 U_BOOT_I2C_ADAP_COMPLETE(i2c08, exynos_i2c_init, s3c24x0_i2c_probe,
1161 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1162 			s3c24x0_i2c_set_bus_speed,
1163 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1164 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 8)
1165 U_BOOT_I2C_ADAP_COMPLETE(i2c09, exynos_i2c_init, s3c24x0_i2c_probe,
1166 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1167 			s3c24x0_i2c_set_bus_speed,
1168 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1169 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 9)
1170 U_BOOT_I2C_ADAP_COMPLETE(i2c10, exynos_i2c_init, s3c24x0_i2c_probe,
1171 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1172 			s3c24x0_i2c_set_bus_speed,
1173 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1174 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 10)
1175 #elif defined(CONFIG_EXYNOS5250)
1176 U_BOOT_I2C_ADAP_COMPLETE(i2c00, exynos_i2c_init, s3c24x0_i2c_probe,
1177 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1178 			s3c24x0_i2c_set_bus_speed,
1179 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1180 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 0)
1181 U_BOOT_I2C_ADAP_COMPLETE(i2c01, exynos_i2c_init, s3c24x0_i2c_probe,
1182 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1183 			s3c24x0_i2c_set_bus_speed,
1184 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1185 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 1)
1186 U_BOOT_I2C_ADAP_COMPLETE(i2c02, exynos_i2c_init, s3c24x0_i2c_probe,
1187 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1188 			s3c24x0_i2c_set_bus_speed,
1189 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1190 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 2)
1191 U_BOOT_I2C_ADAP_COMPLETE(i2c03, exynos_i2c_init, s3c24x0_i2c_probe,
1192 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1193 			s3c24x0_i2c_set_bus_speed,
1194 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1195 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 3)
1196 U_BOOT_I2C_ADAP_COMPLETE(i2c04, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1197 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1198 			s3c24x0_i2c_set_bus_speed,
1199 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1200 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 4)
1201 U_BOOT_I2C_ADAP_COMPLETE(i2c05, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1202 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1203 			s3c24x0_i2c_set_bus_speed,
1204 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1205 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 5)
1206 U_BOOT_I2C_ADAP_COMPLETE(i2c06, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1207 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1208 			s3c24x0_i2c_set_bus_speed,
1209 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1210 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 6)
1211 U_BOOT_I2C_ADAP_COMPLETE(i2c07, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1212 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1213 			s3c24x0_i2c_set_bus_speed,
1214 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1215 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 7)
1216 U_BOOT_I2C_ADAP_COMPLETE(i2c08, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1217 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1218 			s3c24x0_i2c_set_bus_speed,
1219 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1220 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 8)
1221 U_BOOT_I2C_ADAP_COMPLETE(i2c09, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1222 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1223 			s3c24x0_i2c_set_bus_speed,
1224 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1225 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 9)
1226 U_BOOT_I2C_ADAP_COMPLETE(s3c10, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1227 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1228 			s3c24x0_i2c_set_bus_speed,
1229 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1230 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 10)
1231 #elif defined(CONFIG_EXYNOS4)
1232 U_BOOT_I2C_ADAP_COMPLETE(i2c00, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1233 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1234 			s3c24x0_i2c_set_bus_speed,
1235 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1236 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 0)
1237 U_BOOT_I2C_ADAP_COMPLETE(i2c01, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1238 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1239 			s3c24x0_i2c_set_bus_speed,
1240 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1241 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 1)
1242 U_BOOT_I2C_ADAP_COMPLETE(i2c02, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1243 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1244 			s3c24x0_i2c_set_bus_speed,
1245 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1246 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 2)
1247 U_BOOT_I2C_ADAP_COMPLETE(i2c03, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1248 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1249 			s3c24x0_i2c_set_bus_speed,
1250 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1251 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 3)
1252 U_BOOT_I2C_ADAP_COMPLETE(i2c04, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1253 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1254 			s3c24x0_i2c_set_bus_speed,
1255 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1256 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 4)
1257 U_BOOT_I2C_ADAP_COMPLETE(i2c05, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1258 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1259 			s3c24x0_i2c_set_bus_speed,
1260 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1261 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 5)
1262 U_BOOT_I2C_ADAP_COMPLETE(i2c06, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1263 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1264 			s3c24x0_i2c_set_bus_speed,
1265 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1266 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 6)
1267 U_BOOT_I2C_ADAP_COMPLETE(i2c07, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1268 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1269 			s3c24x0_i2c_set_bus_speed,
1270 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1271 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 7)
1272 U_BOOT_I2C_ADAP_COMPLETE(i2c08, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1273 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1274 			s3c24x0_i2c_set_bus_speed,
1275 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1276 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 8)
1277 #else
1278 U_BOOT_I2C_ADAP_COMPLETE(s3c0, s3c24x0_i2c_init, s3c24x0_i2c_probe,
1279 			s3c24x0_i2c_read, s3c24x0_i2c_write,
1280 			s3c24x0_i2c_set_bus_speed,
1281 			CONFIG_SYS_I2C_S3C24X0_SPEED,
1282 			CONFIG_SYS_I2C_S3C24X0_SLAVE, 0)
1283 #endif
1284 #endif /* CONFIG_SYS_I2C */
1285 
1286 #ifdef CONFIG_DM_I2C
1287 static int exynos_hs_i2c_xfer(struct udevice *dev, struct i2c_msg *msg,
1288 			      int nmsgs)
1289 {
1290 	struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev);
1291 	struct exynos5_hsi2c *hsregs = i2c_bus->hsregs;
1292 	int ret;
1293 
1294 	for (; nmsgs > 0; nmsgs--, msg++) {
1295 		if (msg->flags & I2C_M_RD) {
1296 			ret = hsi2c_read(hsregs, msg->addr, 0, 0, msg->buf,
1297 					 msg->len);
1298 		} else {
1299 			ret = hsi2c_write(hsregs, msg->addr, 0, 0, msg->buf,
1300 					  msg->len, true);
1301 		}
1302 		if (ret) {
1303 			exynos5_i2c_reset(i2c_bus);
1304 			return -EREMOTEIO;
1305 		}
1306 	}
1307 
1308 	return 0;
1309 }
1310 
1311 static int s3c24x0_do_msg(struct s3c24x0_i2c_bus *i2c_bus, struct i2c_msg *msg,
1312 			  int seq)
1313 {
1314 	struct s3c24x0_i2c *i2c = i2c_bus->regs;
1315 	bool is_read = msg->flags & I2C_M_RD;
1316 	uint status;
1317 	uint addr;
1318 	int ret, i;
1319 
1320 	if (!seq)
1321 		setbits_le32(&i2c->iiccon, I2CCON_ACKGEN);
1322 
1323 	/* Get the slave chip address going */
1324 	addr = msg->addr << 1;
1325 	writel(addr, &i2c->iicds);
1326 	status = I2C_TXRX_ENA | I2C_START_STOP;
1327 	if (is_read)
1328 		status |= I2C_MODE_MR;
1329 	else
1330 		status |= I2C_MODE_MT;
1331 	writel(status, &i2c->iicstat);
1332 	if (seq)
1333 		read_write_byte(i2c);
1334 
1335 	/* Wait for chip address to transmit */
1336 	ret = WaitForXfer(i2c);
1337 	if (ret)
1338 		goto err;
1339 
1340 	if (is_read) {
1341 		for (i = 0; !ret && i < msg->len; i++) {
1342 			/* disable ACK for final READ */
1343 			if (i == msg->len - 1)
1344 				clrbits_le32(&i2c->iiccon, I2CCON_ACKGEN);
1345 			read_write_byte(i2c);
1346 			ret = WaitForXfer(i2c);
1347 			msg->buf[i] = readl(&i2c->iicds);
1348 		}
1349 		if (ret == I2C_NACK)
1350 			ret = I2C_OK; /* Normal terminated read */
1351 	} else {
1352 		for (i = 0; !ret && i < msg->len; i++) {
1353 			writel(msg->buf[i], &i2c->iicds);
1354 			read_write_byte(i2c);
1355 			ret = WaitForXfer(i2c);
1356 		}
1357 	}
1358 
1359 err:
1360 	return ret;
1361 }
1362 
1363 static int s3c24x0_i2c_xfer(struct udevice *dev, struct i2c_msg *msg,
1364 			    int nmsgs)
1365 {
1366 	struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev);
1367 	struct s3c24x0_i2c *i2c = i2c_bus->regs;
1368 	ulong start_time;
1369 	int ret, i;
1370 
1371 	start_time = get_timer(0);
1372 	while (readl(&i2c->iicstat) & I2CSTAT_BSY) {
1373 		if (get_timer(start_time) > I2C_TIMEOUT_MS) {
1374 			debug("Timeout\n");
1375 			return -ETIMEDOUT;
1376 		}
1377 	}
1378 
1379 	for (ret = 0, i = 0; !ret && i < nmsgs; i++)
1380 		ret = s3c24x0_do_msg(i2c_bus, &msg[i], i);
1381 
1382 	/* Send STOP */
1383 	writel(I2C_MODE_MR | I2C_TXRX_ENA, &i2c->iicstat);
1384 	read_write_byte(i2c);
1385 
1386 	return ret ? -EREMOTEIO : 0;
1387 }
1388 
1389 static int s3c_i2c_ofdata_to_platdata(struct udevice *dev)
1390 {
1391 	const void *blob = gd->fdt_blob;
1392 	struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev);
1393 	int node, flags;
1394 
1395 	i2c_bus->is_highspeed = dev_get_driver_data(dev);
1396 	node = dev->of_offset;
1397 
1398 	if (i2c_bus->is_highspeed) {
1399 		flags = PINMUX_FLAG_HS_MODE;
1400 		i2c_bus->hsregs = (struct exynos5_hsi2c *)dev_get_addr(dev);
1401 	} else {
1402 		flags = 0;
1403 		i2c_bus->regs = (struct s3c24x0_i2c *)dev_get_addr(dev);
1404 	}
1405 
1406 	i2c_bus->id = pinmux_decode_periph_id(blob, node);
1407 
1408 	i2c_bus->clock_frequency = fdtdec_get_int(blob, node,
1409 						  "clock-frequency", 100000);
1410 	i2c_bus->node = node;
1411 	i2c_bus->bus_num = dev->seq;
1412 
1413 	exynos_pinmux_config(i2c_bus->id, flags);
1414 
1415 	i2c_bus->active = true;
1416 
1417 	return 0;
1418 }
1419 
1420 static const struct dm_i2c_ops s3c_i2c_ops = {
1421 	.xfer		= s3c24x0_i2c_xfer,
1422 	.probe_chip	= s3c24x0_i2c_probe,
1423 	.set_bus_speed	= s3c24x0_i2c_set_bus_speed,
1424 };
1425 
1426 static const struct udevice_id s3c_i2c_ids[] = {
1427 	{ .compatible = "samsung,s3c2440-i2c", .data = EXYNOS_I2C_STD },
1428 	{ }
1429 };
1430 
1431 U_BOOT_DRIVER(i2c_s3c) = {
1432 	.name	= "i2c_s3c",
1433 	.id	= UCLASS_I2C,
1434 	.of_match = s3c_i2c_ids,
1435 	.ofdata_to_platdata = s3c_i2c_ofdata_to_platdata,
1436 	.per_child_auto_alloc_size = sizeof(struct dm_i2c_chip),
1437 	.priv_auto_alloc_size = sizeof(struct s3c24x0_i2c_bus),
1438 	.ops	= &s3c_i2c_ops,
1439 };
1440 
1441 /*
1442  * TODO(sjg@chromium.org): Move this to a separate file when everything uses
1443  * driver model
1444  */
1445 static const struct dm_i2c_ops exynos_hs_i2c_ops = {
1446 	.xfer		= exynos_hs_i2c_xfer,
1447 	.probe_chip	= s3c24x0_i2c_probe,
1448 	.set_bus_speed	= s3c24x0_i2c_set_bus_speed,
1449 };
1450 
1451 static const struct udevice_id exynos_hs_i2c_ids[] = {
1452 	{ .compatible = "samsung,exynos5-hsi2c", .data = EXYNOS_I2C_HS },
1453 	{ }
1454 };
1455 
1456 U_BOOT_DRIVER(hs_i2c) = {
1457 	.name	= "i2c_s3c_hs",
1458 	.id	= UCLASS_I2C,
1459 	.of_match = exynos_hs_i2c_ids,
1460 	.ofdata_to_platdata = s3c_i2c_ofdata_to_platdata,
1461 	.per_child_auto_alloc_size = sizeof(struct dm_i2c_chip),
1462 	.priv_auto_alloc_size = sizeof(struct s3c24x0_i2c_bus),
1463 	.ops	= &exynos_hs_i2c_ops,
1464 };
1465 #endif /* CONFIG_DM_I2C */
1466