xref: /openbmc/u-boot/drivers/i2c/omap24xx_i2c.c (revision ed4708aa)
1 /*
2  * Basic I2C functions
3  *
4  * Copyright (c) 2004 Texas Instruments
5  *
6  * This package is free software;  you can redistribute it and/or
7  * modify it under the terms of the license found in the file
8  * named COPYING that should have accompanied this file.
9  *
10  * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
11  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
12  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
13  *
14  * Author: Jian Zhang jzhang@ti.com, Texas Instruments
15  *
16  * Copyright (c) 2003 Wolfgang Denk, wd@denx.de
17  * Rewritten to fit into the current U-Boot framework
18  *
19  * Adapted for OMAP2420 I2C, r-woodruff2@ti.com
20  *
21  * Copyright (c) 2013 Lubomir Popov <lpopov@mm-sol.com>, MM Solutions
22  * New i2c_read, i2c_write and i2c_probe functions, tested on OMAP4
23  * (4430/60/70), OMAP5 (5430) and AM335X (3359); should work on older
24  * OMAPs and derivatives as well. The only anticipated exception would
25  * be the OMAP2420, which shall require driver modification.
26  * - Rewritten i2c_read to operate correctly with all types of chips
27  *   (old function could not read consistent data from some I2C slaves).
28  * - Optimized i2c_write.
29  * - New i2c_probe, performs write access vs read. The old probe could
30  *   hang the system under certain conditions (e.g. unconfigured pads).
31  * - The read/write/probe functions try to identify unconfigured bus.
32  * - Status functions now read irqstatus_raw as per TRM guidelines
33  *   (except for OMAP243X and OMAP34XX).
34  * - Driver now supports up to I2C5 (OMAP5).
35  *
36  * Copyright (c) 2014 Hannes Schmelzer <oe5hpm@oevsv.at>, B&R
37  * - Added support for set_speed
38  *
39  */
40 
41 #include <common.h>
42 #include <i2c.h>
43 
44 #include <asm/arch/i2c.h>
45 #include <asm/io.h>
46 
47 #include "omap24xx_i2c.h"
48 
49 DECLARE_GLOBAL_DATA_PTR;
50 
51 #define I2C_TIMEOUT	1000
52 
53 /* Absolutely safe for status update at 100 kHz I2C: */
54 #define I2C_WAIT	200
55 
56 static int wait_for_bb(struct i2c_adapter *adap);
57 static struct i2c *omap24_get_base(struct i2c_adapter *adap);
58 static u16 wait_for_event(struct i2c_adapter *adap);
59 static void flush_fifo(struct i2c_adapter *adap);
60 static int omap24_i2c_findpsc(u32 *pscl, u32 *psch, uint speed)
61 {
62 	unsigned int sampleclk, prescaler;
63 	int fsscll, fssclh;
64 
65 	speed <<= 1;
66 	prescaler = 0;
67 	/*
68 	 * some divisors may cause a precission loss, but shouldn't
69 	 * be a big thing, because i2c_clk is then allready very slow.
70 	 */
71 	while (prescaler <= 0xFF) {
72 		sampleclk = I2C_IP_CLK / (prescaler+1);
73 
74 		fsscll = sampleclk / speed;
75 		fssclh = fsscll;
76 		fsscll -= I2C_FASTSPEED_SCLL_TRIM;
77 		fssclh -= I2C_FASTSPEED_SCLH_TRIM;
78 
79 		if (((fsscll > 0) && (fssclh > 0)) &&
80 		    ((fsscll <= (255-I2C_FASTSPEED_SCLL_TRIM)) &&
81 		    (fssclh <= (255-I2C_FASTSPEED_SCLH_TRIM)))) {
82 			if (pscl)
83 				*pscl = fsscll;
84 			if (psch)
85 				*psch = fssclh;
86 
87 			return prescaler;
88 		}
89 		prescaler++;
90 	}
91 	return -1;
92 }
93 static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
94 {
95 	struct i2c *i2c_base = omap24_get_base(adap);
96 	int psc, fsscll = 0, fssclh = 0;
97 	int hsscll = 0, hssclh = 0;
98 	u32 scll = 0, sclh = 0;
99 
100 	if (speed >= OMAP_I2C_HIGH_SPEED) {
101 		/* High speed */
102 		psc = I2C_IP_CLK / I2C_INTERNAL_SAMPLING_CLK;
103 		psc -= 1;
104 		if (psc < I2C_PSC_MIN) {
105 			printf("Error : I2C unsupported prescaler %d\n", psc);
106 			return -1;
107 		}
108 
109 		/* For first phase of HS mode */
110 		fsscll = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
111 
112 		fssclh = fsscll;
113 
114 		fsscll -= I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM;
115 		fssclh -= I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM;
116 		if (((fsscll < 0) || (fssclh < 0)) ||
117 		    ((fsscll > 255) || (fssclh > 255))) {
118 			puts("Error : I2C initializing first phase clock\n");
119 			return -1;
120 		}
121 
122 		/* For second phase of HS mode */
123 		hsscll = hssclh = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
124 
125 		hsscll -= I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM;
126 		hssclh -= I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM;
127 		if (((fsscll < 0) || (fssclh < 0)) ||
128 		    ((fsscll > 255) || (fssclh > 255))) {
129 			puts("Error : I2C initializing second phase clock\n");
130 			return -1;
131 		}
132 
133 		scll = (unsigned int)hsscll << 8 | (unsigned int)fsscll;
134 		sclh = (unsigned int)hssclh << 8 | (unsigned int)fssclh;
135 
136 	} else {
137 		/* Standard and fast speed */
138 		psc = omap24_i2c_findpsc(&scll, &sclh, speed);
139 		if (0 > psc) {
140 			puts("Error : I2C initializing clock\n");
141 			return -1;
142 		}
143 	}
144 
145 	adap->speed	= speed;
146 	adap->waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */
147 	writew(0, &i2c_base->con);
148 	writew(psc, &i2c_base->psc);
149 	writew(scll, &i2c_base->scll);
150 	writew(sclh, &i2c_base->sclh);
151 	writew(I2C_CON_EN, &i2c_base->con);
152 	writew(0xFFFF, &i2c_base->stat);	/* clear all pending status */
153 
154 	return 0;
155 }
156 
157 static void omap24_i2c_deblock(struct i2c_adapter *adap)
158 {
159 	struct i2c *i2c_base = omap24_get_base(adap);
160 	int i;
161 	u16 systest;
162 	u16 orgsystest;
163 
164 	/* set test mode ST_EN = 1 */
165 	orgsystest = readw(&i2c_base->systest);
166 	systest = orgsystest;
167 	/* enable testmode */
168 	systest |= I2C_SYSTEST_ST_EN;
169 	writew(systest, &i2c_base->systest);
170 	systest &= ~I2C_SYSTEST_TMODE_MASK;
171 	systest |= 3 << I2C_SYSTEST_TMODE_SHIFT;
172 	writew(systest, &i2c_base->systest);
173 
174 	/* set SCL, SDA  = 1 */
175 	systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
176 	writew(systest, &i2c_base->systest);
177 	udelay(10);
178 
179 	/* toggle scl 9 clocks */
180 	for (i = 0; i < 9; i++) {
181 		/* SCL = 0 */
182 		systest &= ~I2C_SYSTEST_SCL_O;
183 		writew(systest, &i2c_base->systest);
184 		udelay(10);
185 		/* SCL = 1 */
186 		systest |= I2C_SYSTEST_SCL_O;
187 		writew(systest, &i2c_base->systest);
188 		udelay(10);
189 	}
190 
191 	/* send stop */
192 	systest &= ~I2C_SYSTEST_SDA_O;
193 	writew(systest, &i2c_base->systest);
194 	udelay(10);
195 	systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
196 	writew(systest, &i2c_base->systest);
197 	udelay(10);
198 
199 	/* restore original mode */
200 	writew(orgsystest, &i2c_base->systest);
201 }
202 
203 static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
204 {
205 	struct i2c *i2c_base = omap24_get_base(adap);
206 	int timeout = I2C_TIMEOUT;
207 	int deblock = 1;
208 
209 retry:
210 	if (readw(&i2c_base->con) & I2C_CON_EN) {
211 		writew(0, &i2c_base->con);
212 		udelay(50000);
213 	}
214 
215 	writew(0x2, &i2c_base->sysc); /* for ES2 after soft reset */
216 	udelay(1000);
217 
218 	writew(I2C_CON_EN, &i2c_base->con);
219 	while (!(readw(&i2c_base->syss) & I2C_SYSS_RDONE) && timeout--) {
220 		if (timeout <= 0) {
221 			puts("ERROR: Timeout in soft-reset\n");
222 			return;
223 		}
224 		udelay(1000);
225 	}
226 
227 	if (0 != omap24_i2c_setspeed(adap, speed)) {
228 		printf("ERROR: failed to setup I2C bus-speed!\n");
229 		return;
230 	}
231 
232 	/* own address */
233 	writew(slaveadd, &i2c_base->oa);
234 
235 #if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
236 	/*
237 	 * Have to enable interrupts for OMAP2/3, these IPs don't have
238 	 * an 'irqstatus_raw' register and we shall have to poll 'stat'
239 	 */
240 	writew(I2C_IE_XRDY_IE | I2C_IE_RRDY_IE | I2C_IE_ARDY_IE |
241 	       I2C_IE_NACK_IE | I2C_IE_AL_IE, &i2c_base->ie);
242 #endif
243 	udelay(1000);
244 	flush_fifo(adap);
245 	writew(0xFFFF, &i2c_base->stat);
246 
247 	/* Handle possible failed I2C state */
248 	if (wait_for_bb(adap))
249 		if (deblock == 1) {
250 			omap24_i2c_deblock(adap);
251 			deblock = 0;
252 			goto retry;
253 		}
254 }
255 
256 static void flush_fifo(struct i2c_adapter *adap)
257 {
258 	struct i2c *i2c_base = omap24_get_base(adap);
259 	u16 stat;
260 
261 	/*
262 	 * note: if you try and read data when its not there or ready
263 	 * you get a bus error
264 	 */
265 	while (1) {
266 		stat = readw(&i2c_base->stat);
267 		if (stat == I2C_STAT_RRDY) {
268 			readb(&i2c_base->data);
269 			writew(I2C_STAT_RRDY, &i2c_base->stat);
270 			udelay(1000);
271 		} else
272 			break;
273 	}
274 }
275 
276 /*
277  * i2c_probe: Use write access. Allows to identify addresses that are
278  *            write-only (like the config register of dual-port EEPROMs)
279  */
280 static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
281 {
282 	struct i2c *i2c_base = omap24_get_base(adap);
283 	u16 status;
284 	int res = 1; /* default = fail */
285 
286 	if (chip == readw(&i2c_base->oa))
287 		return res;
288 
289 	/* Wait until bus is free */
290 	if (wait_for_bb(adap))
291 		return res;
292 
293 	/* No data transfer, slave addr only */
294 	writew(chip, &i2c_base->sa);
295 	/* Stop bit needed here */
296 	writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
297 	       I2C_CON_STP, &i2c_base->con);
298 
299 	status = wait_for_event(adap);
300 
301 	if ((status & ~I2C_STAT_XRDY) == 0 || (status & I2C_STAT_AL)) {
302 		/*
303 		 * With current high-level command implementation, notifying
304 		 * the user shall flood the console with 127 messages. If
305 		 * silent exit is desired upon unconfigured bus, remove the
306 		 * following 'if' section:
307 		 */
308 		if (status == I2C_STAT_XRDY)
309 			printf("i2c_probe: pads on bus %d probably not configured (status=0x%x)\n",
310 			       adap->hwadapnr, status);
311 
312 		goto pr_exit;
313 	}
314 
315 	/* Check for ACK (!NAK) */
316 	if (!(status & I2C_STAT_NACK)) {
317 		res = 0;				/* Device found */
318 		udelay(adap->waitdelay);/* Required by AM335X in SPL */
319 		/* Abort transfer (force idle state) */
320 		writew(I2C_CON_MST | I2C_CON_TRX, &i2c_base->con); /* Reset */
321 		udelay(1000);
322 		writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_TRX |
323 		       I2C_CON_STP, &i2c_base->con);		/* STP */
324 	}
325 pr_exit:
326 	flush_fifo(adap);
327 	writew(0xFFFF, &i2c_base->stat);
328 	return res;
329 }
330 
331 /*
332  * i2c_read: Function now uses a single I2C read transaction with bulk transfer
333  *           of the requested number of bytes (note that the 'i2c md' command
334  *           limits this to 16 bytes anyway). If CONFIG_I2C_REPEATED_START is
335  *           defined in the board config header, this transaction shall be with
336  *           Repeated Start (Sr) between the address and data phases; otherwise
337  *           Stop-Start (P-S) shall be used (some I2C chips do require a P-S).
338  *           The address (reg offset) may be 0, 1 or 2 bytes long.
339  *           Function now reads correctly from chips that return more than one
340  *           byte of data per addressed register (like TI temperature sensors),
341  *           or that do not need a register address at all (such as some clock
342  *           distributors).
343  */
344 static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
345 			   int alen, uchar *buffer, int len)
346 {
347 	struct i2c *i2c_base = omap24_get_base(adap);
348 	int i2c_error = 0;
349 	u16 status;
350 
351 	if (alen < 0) {
352 		puts("I2C read: addr len < 0\n");
353 		return 1;
354 	}
355 	if (len < 0) {
356 		puts("I2C read: data len < 0\n");
357 		return 1;
358 	}
359 	if (buffer == NULL) {
360 		puts("I2C read: NULL pointer passed\n");
361 		return 1;
362 	}
363 
364 	if (alen > 2) {
365 		printf("I2C read: addr len %d not supported\n", alen);
366 		return 1;
367 	}
368 
369 	if (addr + len > (1 << 16)) {
370 		puts("I2C read: address out of range\n");
371 		return 1;
372 	}
373 
374 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
375 	/*
376 	 * EEPROM chips that implement "address overflow" are ones
377 	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
378 	 * address and the extra bits end up in the "chip address"
379 	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like
380 	 * four 256 byte chips.
381 	 *
382 	 * Note that we consider the length of the address field to
383 	 * still be one byte because the extra address bits are
384 	 * hidden in the chip address.
385 	 */
386 	if (alen > 0)
387 		chip |= ((addr >> (alen * 8)) &
388 			 CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
389 #endif
390 
391 	/* Wait until bus not busy */
392 	if (wait_for_bb(adap))
393 		return 1;
394 
395 	/* Zero, one or two bytes reg address (offset) */
396 	writew(alen, &i2c_base->cnt);
397 	/* Set slave address */
398 	writew(chip, &i2c_base->sa);
399 
400 	if (alen) {
401 		/* Must write reg offset first */
402 #ifdef CONFIG_I2C_REPEATED_START
403 		/* No stop bit, use Repeated Start (Sr) */
404 		writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT |
405 		       I2C_CON_TRX, &i2c_base->con);
406 #else
407 		/* Stop - Start (P-S) */
408 		writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP |
409 		       I2C_CON_TRX, &i2c_base->con);
410 #endif
411 		/* Send register offset */
412 		while (1) {
413 			status = wait_for_event(adap);
414 			/* Try to identify bus that is not padconf'd for I2C */
415 			if (status == I2C_STAT_XRDY) {
416 				i2c_error = 2;
417 				printf("i2c_read (addr phase): pads on bus %d probably not configured (status=0x%x)\n",
418 				       adap->hwadapnr, status);
419 				goto rd_exit;
420 			}
421 			if (status == 0 || (status & I2C_STAT_NACK)) {
422 				i2c_error = 1;
423 				printf("i2c_read: error waiting for addr ACK (status=0x%x)\n",
424 				       status);
425 				goto rd_exit;
426 			}
427 			if (alen) {
428 				if (status & I2C_STAT_XRDY) {
429 					alen--;
430 					/* Do we have to use byte access? */
431 					writeb((addr >> (8 * alen)) & 0xff,
432 					       &i2c_base->data);
433 					writew(I2C_STAT_XRDY, &i2c_base->stat);
434 				}
435 			}
436 			if (status & I2C_STAT_ARDY) {
437 				writew(I2C_STAT_ARDY, &i2c_base->stat);
438 				break;
439 			}
440 		}
441 	}
442 	/* Set slave address */
443 	writew(chip, &i2c_base->sa);
444 	/* Read len bytes from slave */
445 	writew(len, &i2c_base->cnt);
446 	/* Need stop bit here */
447 	writew(I2C_CON_EN | I2C_CON_MST |
448 	       I2C_CON_STT | I2C_CON_STP,
449 	       &i2c_base->con);
450 
451 	/* Receive data */
452 	while (1) {
453 		status = wait_for_event(adap);
454 		/*
455 		 * Try to identify bus that is not padconf'd for I2C. This
456 		 * state could be left over from previous transactions if
457 		 * the address phase is skipped due to alen=0.
458 		 */
459 		if (status == I2C_STAT_XRDY) {
460 			i2c_error = 2;
461 			printf("i2c_read (data phase): pads on bus %d probably not configured (status=0x%x)\n",
462 			       adap->hwadapnr, status);
463 			goto rd_exit;
464 		}
465 		if (status == 0 || (status & I2C_STAT_NACK)) {
466 			i2c_error = 1;
467 			goto rd_exit;
468 		}
469 		if (status & I2C_STAT_RRDY) {
470 			*buffer++ = readb(&i2c_base->data);
471 			writew(I2C_STAT_RRDY, &i2c_base->stat);
472 		}
473 		if (status & I2C_STAT_ARDY) {
474 			writew(I2C_STAT_ARDY, &i2c_base->stat);
475 			break;
476 		}
477 	}
478 
479 rd_exit:
480 	flush_fifo(adap);
481 	writew(0xFFFF, &i2c_base->stat);
482 	return i2c_error;
483 }
484 
485 /* i2c_write: Address (reg offset) may be 0, 1 or 2 bytes long. */
486 static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
487 			    int alen, uchar *buffer, int len)
488 {
489 	struct i2c *i2c_base = omap24_get_base(adap);
490 	int i;
491 	u16 status;
492 	int i2c_error = 0;
493 	int timeout = I2C_TIMEOUT;
494 
495 	if (alen < 0) {
496 		puts("I2C write: addr len < 0\n");
497 		return 1;
498 	}
499 
500 	if (len < 0) {
501 		puts("I2C write: data len < 0\n");
502 		return 1;
503 	}
504 
505 	if (buffer == NULL) {
506 		puts("I2C write: NULL pointer passed\n");
507 		return 1;
508 	}
509 
510 	if (alen > 2) {
511 		printf("I2C write: addr len %d not supported\n", alen);
512 		return 1;
513 	}
514 
515 	if (addr + len > (1 << 16)) {
516 		printf("I2C write: address 0x%x + 0x%x out of range\n",
517 		       addr, len);
518 		return 1;
519 	}
520 
521 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
522 	/*
523 	 * EEPROM chips that implement "address overflow" are ones
524 	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
525 	 * address and the extra bits end up in the "chip address"
526 	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like
527 	 * four 256 byte chips.
528 	 *
529 	 * Note that we consider the length of the address field to
530 	 * still be one byte because the extra address bits are
531 	 * hidden in the chip address.
532 	 */
533 	if (alen > 0)
534 		chip |= ((addr >> (alen * 8)) &
535 			 CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
536 #endif
537 
538 	/* Wait until bus not busy */
539 	if (wait_for_bb(adap))
540 		return 1;
541 
542 	/* Start address phase - will write regoffset + len bytes data */
543 	writew(alen + len, &i2c_base->cnt);
544 	/* Set slave address */
545 	writew(chip, &i2c_base->sa);
546 	/* Stop bit needed here */
547 	writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
548 	       I2C_CON_STP, &i2c_base->con);
549 
550 	while (alen) {
551 		/* Must write reg offset (one or two bytes) */
552 		status = wait_for_event(adap);
553 		/* Try to identify bus that is not padconf'd for I2C */
554 		if (status == I2C_STAT_XRDY) {
555 			i2c_error = 2;
556 			printf("i2c_write: pads on bus %d probably not configured (status=0x%x)\n",
557 			       adap->hwadapnr, status);
558 			goto wr_exit;
559 		}
560 		if (status == 0 || (status & I2C_STAT_NACK)) {
561 			i2c_error = 1;
562 			printf("i2c_write: error waiting for addr ACK (status=0x%x)\n",
563 			       status);
564 			goto wr_exit;
565 		}
566 		if (status & I2C_STAT_XRDY) {
567 			alen--;
568 			writeb((addr >> (8 * alen)) & 0xff, &i2c_base->data);
569 			writew(I2C_STAT_XRDY, &i2c_base->stat);
570 		} else {
571 			i2c_error = 1;
572 			printf("i2c_write: bus not ready for addr Tx (status=0x%x)\n",
573 			       status);
574 			goto wr_exit;
575 		}
576 	}
577 	/* Address phase is over, now write data */
578 	for (i = 0; i < len; i++) {
579 		status = wait_for_event(adap);
580 		if (status == 0 || (status & I2C_STAT_NACK)) {
581 			i2c_error = 1;
582 			printf("i2c_write: error waiting for data ACK (status=0x%x)\n",
583 			       status);
584 			goto wr_exit;
585 		}
586 		if (status & I2C_STAT_XRDY) {
587 			writeb(buffer[i], &i2c_base->data);
588 			writew(I2C_STAT_XRDY, &i2c_base->stat);
589 		} else {
590 			i2c_error = 1;
591 			printf("i2c_write: bus not ready for data Tx (i=%d)\n",
592 			       i);
593 			goto wr_exit;
594 		}
595 	}
596 	/*
597 	 * poll ARDY bit for making sure that last byte really has been
598 	 * transferred on the bus.
599 	 */
600 	do {
601 		status = wait_for_event(adap);
602 	} while (!(status & I2C_STAT_ARDY) && timeout--);
603 	if (timeout <= 0)
604 		printf("i2c_write: timed out writig last byte!\n");
605 
606 wr_exit:
607 	flush_fifo(adap);
608 	writew(0xFFFF, &i2c_base->stat);
609 	return i2c_error;
610 }
611 
612 /*
613  * Wait for the bus to be free by checking the Bus Busy (BB)
614  * bit to become clear
615  */
616 static int wait_for_bb(struct i2c_adapter *adap)
617 {
618 	struct i2c *i2c_base = omap24_get_base(adap);
619 	int timeout = I2C_TIMEOUT;
620 	u16 stat;
621 
622 	writew(0xFFFF, &i2c_base->stat);	/* clear current interrupts...*/
623 #if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
624 	while ((stat = readw(&i2c_base->stat) & I2C_STAT_BB) && timeout--) {
625 #else
626 	/* Read RAW status */
627 	while ((stat = readw(&i2c_base->irqstatus_raw) &
628 		I2C_STAT_BB) && timeout--) {
629 #endif
630 		writew(stat, &i2c_base->stat);
631 		udelay(adap->waitdelay);
632 	}
633 
634 	if (timeout <= 0) {
635 		printf("Timed out in wait_for_bb: status=%04x\n",
636 		       stat);
637 		return 1;
638 	}
639 	writew(0xFFFF, &i2c_base->stat);	 /* clear delayed stuff*/
640 	return 0;
641 }
642 
643 /*
644  * Wait for the I2C controller to complete current action
645  * and update status
646  */
647 static u16 wait_for_event(struct i2c_adapter *adap)
648 {
649 	struct i2c *i2c_base = omap24_get_base(adap);
650 	u16 status;
651 	int timeout = I2C_TIMEOUT;
652 
653 	do {
654 		udelay(adap->waitdelay);
655 #if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
656 		status = readw(&i2c_base->stat);
657 #else
658 		/* Read RAW status */
659 		status = readw(&i2c_base->irqstatus_raw);
660 #endif
661 	} while (!(status &
662 		   (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
663 		    I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
664 		    I2C_STAT_AL)) && timeout--);
665 
666 	if (timeout <= 0) {
667 		printf("Timed out in wait_for_event: status=%04x\n",
668 		       status);
669 		/*
670 		 * If status is still 0 here, probably the bus pads have
671 		 * not been configured for I2C, and/or pull-ups are missing.
672 		 */
673 		printf("Check if pads/pull-ups of bus %d are properly configured\n",
674 		       adap->hwadapnr);
675 		writew(0xFFFF, &i2c_base->stat);
676 		status = 0;
677 	}
678 
679 	return status;
680 }
681 
682 static struct i2c *omap24_get_base(struct i2c_adapter *adap)
683 {
684 	switch (adap->hwadapnr) {
685 	case 0:
686 		return (struct i2c *)I2C_BASE1;
687 		break;
688 	case 1:
689 		return (struct i2c *)I2C_BASE2;
690 		break;
691 #if (I2C_BUS_MAX > 2)
692 	case 2:
693 		return (struct i2c *)I2C_BASE3;
694 		break;
695 #if (I2C_BUS_MAX > 3)
696 	case 3:
697 		return (struct i2c *)I2C_BASE4;
698 		break;
699 #if (I2C_BUS_MAX > 4)
700 	case 4:
701 		return (struct i2c *)I2C_BASE5;
702 		break;
703 #endif
704 #endif
705 #endif
706 	default:
707 		printf("wrong hwadapnr: %d\n", adap->hwadapnr);
708 		break;
709 	}
710 	return NULL;
711 }
712 
713 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED1)
714 #define CONFIG_SYS_OMAP24_I2C_SPEED1 CONFIG_SYS_OMAP24_I2C_SPEED
715 #endif
716 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE1)
717 #define CONFIG_SYS_OMAP24_I2C_SLAVE1 CONFIG_SYS_OMAP24_I2C_SLAVE
718 #endif
719 
720 U_BOOT_I2C_ADAP_COMPLETE(omap24_0, omap24_i2c_init, omap24_i2c_probe,
721 			 omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed,
722 			 CONFIG_SYS_OMAP24_I2C_SPEED,
723 			 CONFIG_SYS_OMAP24_I2C_SLAVE,
724 			 0)
725 U_BOOT_I2C_ADAP_COMPLETE(omap24_1, omap24_i2c_init, omap24_i2c_probe,
726 			 omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed,
727 			 CONFIG_SYS_OMAP24_I2C_SPEED1,
728 			 CONFIG_SYS_OMAP24_I2C_SLAVE1,
729 			 1)
730 #if (I2C_BUS_MAX > 2)
731 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED2)
732 #define CONFIG_SYS_OMAP24_I2C_SPEED2 CONFIG_SYS_OMAP24_I2C_SPEED
733 #endif
734 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE2)
735 #define CONFIG_SYS_OMAP24_I2C_SLAVE2 CONFIG_SYS_OMAP24_I2C_SLAVE
736 #endif
737 
738 U_BOOT_I2C_ADAP_COMPLETE(omap24_2, omap24_i2c_init, omap24_i2c_probe,
739 			 omap24_i2c_read, omap24_i2c_write, NULL,
740 			 CONFIG_SYS_OMAP24_I2C_SPEED2,
741 			 CONFIG_SYS_OMAP24_I2C_SLAVE2,
742 			 2)
743 #if (I2C_BUS_MAX > 3)
744 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED3)
745 #define CONFIG_SYS_OMAP24_I2C_SPEED3 CONFIG_SYS_OMAP24_I2C_SPEED
746 #endif
747 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE3)
748 #define CONFIG_SYS_OMAP24_I2C_SLAVE3 CONFIG_SYS_OMAP24_I2C_SLAVE
749 #endif
750 
751 U_BOOT_I2C_ADAP_COMPLETE(omap24_3, omap24_i2c_init, omap24_i2c_probe,
752 			 omap24_i2c_read, omap24_i2c_write, NULL,
753 			 CONFIG_SYS_OMAP24_I2C_SPEED3,
754 			 CONFIG_SYS_OMAP24_I2C_SLAVE3,
755 			 3)
756 #if (I2C_BUS_MAX > 4)
757 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED4)
758 #define CONFIG_SYS_OMAP24_I2C_SPEED4 CONFIG_SYS_OMAP24_I2C_SPEED
759 #endif
760 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE4)
761 #define CONFIG_SYS_OMAP24_I2C_SLAVE4 CONFIG_SYS_OMAP24_I2C_SLAVE
762 #endif
763 
764 U_BOOT_I2C_ADAP_COMPLETE(omap24_4, omap24_i2c_init, omap24_i2c_probe,
765 			 omap24_i2c_read, omap24_i2c_write, NULL,
766 			 CONFIG_SYS_OMAP24_I2C_SPEED4,
767 			 CONFIG_SYS_OMAP24_I2C_SLAVE4,
768 			 4)
769 #endif
770 #endif
771 #endif
772