aboutsummaryrefslogtreecommitdiff
path: root/drivers/i2c/designware_i2c.c
blob: e60fd0a41903b811a98f0bcc88bf6ac8ae9519de (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
/*
 * (C) Copyright 2009
 * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <dm.h>
#include <i2c.h>
#include <pci.h>
#include <asm/io.h>
#include "designware_i2c.h"

struct dw_scl_sda_cfg {
	u32 ss_hcnt;
	u32 fs_hcnt;
	u32 ss_lcnt;
	u32 fs_lcnt;
	u32 sda_hold;
};

#ifdef CONFIG_X86
/* BayTrail HCNT/LCNT/SDA hold time */
static struct dw_scl_sda_cfg byt_config = {
	.ss_hcnt = 0x200,
	.fs_hcnt = 0x55,
	.ss_lcnt = 0x200,
	.fs_lcnt = 0x99,
	.sda_hold = 0x6,
};
#endif

struct dw_i2c {
	struct i2c_regs *regs;
	struct dw_scl_sda_cfg *scl_sda_cfg;
};

#ifdef CONFIG_SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED
static void dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
{
	u32 ena = enable ? IC_ENABLE_0B : 0;

	writel(ena, &i2c_base->ic_enable);
}
#else
static void dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
{
	u32 ena = enable ? IC_ENABLE_0B : 0;
	int timeout = 100;

	do {
		writel(ena, &i2c_base->ic_enable);
		if ((readl(&i2c_base->ic_enable_status) & IC_ENABLE_0B) == ena)
			return;

		/*
		 * Wait 10 times the signaling period of the highest I2C
		 * transfer supported by the driver (for 400KHz this is
		 * 25us) as described in the DesignWare I2C databook.
		 */
		udelay(25);
	} while (timeout--);

	printf("timeout in %sabling I2C adapter\n", enable ? "en" : "dis");
}
#endif

/*
 * i2c_set_bus_speed - Set the i2c speed
 * @speed:	required i2c speed
 *
 * Set the i2c speed.
 */
static unsigned int __dw_i2c_set_bus_speed(struct i2c_regs *i2c_base,
					   struct dw_scl_sda_cfg *scl_sda_cfg,
					   unsigned int speed)
{
	unsigned int cntl;
	unsigned int hcnt, lcnt;
	int i2c_spd;

	if (speed >= I2C_MAX_SPEED)
		i2c_spd = IC_SPEED_MODE_MAX;
	else if (speed >= I2C_FAST_SPEED)
		i2c_spd = IC_SPEED_MODE_FAST;
	else
		i2c_spd = IC_SPEED_MODE_STANDARD;

	/* to set speed cltr must be disabled */
	dw_i2c_enable(i2c_base, false);

	cntl = (readl(&i2c_base->ic_con) & (~IC_CON_SPD_MSK));

	switch (i2c_spd) {
#ifndef CONFIG_X86 /* No High-speed for BayTrail yet */
	case IC_SPEED_MODE_MAX:
		cntl |= IC_CON_SPD_SS;
		if (scl_sda_cfg) {
			hcnt = scl_sda_cfg->fs_hcnt;
			lcnt = scl_sda_cfg->fs_lcnt;
		} else {
			hcnt = (IC_CLK * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO;
			lcnt = (IC_CLK * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO;
		}
		writel(hcnt, &i2c_base->ic_hs_scl_hcnt);
		writel(lcnt, &i2c_base->ic_hs_scl_lcnt);
		break;
#endif

	case IC_SPEED_MODE_STANDARD:
		cntl |= IC_CON_SPD_SS;
		if (scl_sda_cfg) {
			hcnt = scl_sda_cfg->ss_hcnt;
			lcnt = scl_sda_cfg->ss_lcnt;
		} else {
			hcnt = (IC_CLK * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO;
			lcnt = (IC_CLK * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO;
		}
		writel(hcnt, &i2c_base->ic_ss_scl_hcnt);
		writel(lcnt, &i2c_base->ic_ss_scl_lcnt);
		break;

	case IC_SPEED_MODE_FAST:
	default:
		cntl |= IC_CON_SPD_FS;
		if (scl_sda_cfg) {
			hcnt = scl_sda_cfg->fs_hcnt;
			lcnt = scl_sda_cfg->fs_lcnt;
		} else {
			hcnt = (IC_CLK * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO;
			lcnt = (IC_CLK * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO;
		}
		writel(hcnt, &i2c_base->ic_fs_scl_hcnt);
		writel(lcnt, &i2c_base->ic_fs_scl_lcnt);
		break;
	}

	writel(cntl, &i2c_base->ic_con);

	/* Configure SDA Hold Time if required */
	if (scl_sda_cfg)
		writel(scl_sda_cfg->sda_hold, &i2c_base->ic_sda_hold);

	/* Enable back i2c now speed set */
	dw_i2c_enable(i2c_base, true);

	return 0;
}

/*
 * i2c_setaddress - Sets the target slave address
 * @i2c_addr:	target i2c address
 *
 * Sets the target slave address.
 */
static void i2c_setaddress(struct i2c_regs *i2c_base, unsigned int i2c_addr)
{
	/* Disable i2c */
	dw_i2c_enable(i2c_base, false);

	writel(i2c_addr, &i2c_base->ic_tar);

	/* Enable i2c */
	dw_i2c_enable(i2c_base, true);
}

/*
 * i2c_flush_rxfifo - Flushes the i2c RX FIFO
 *
 * Flushes the i2c RX FIFO
 */
static void i2c_flush_rxfifo(struct i2c_regs *i2c_base)
{
	while (readl(&i2c_base->ic_status) & IC_STATUS_RFNE)
		readl(&i2c_base->ic_cmd_data);
}

/*
 * i2c_wait_for_bb - Waits for bus busy
 *
 * Waits for bus busy
 */
static int i2c_wait_for_bb(struct i2c_regs *i2c_base)
{
	unsigned long start_time_bb = get_timer(0);

	while ((readl(&i2c_base->ic_status) & IC_STATUS_MA) ||
	       !(readl(&i2c_base->ic_status) & IC_STATUS_TFE)) {

		/* Evaluate timeout */
		if (get_timer(start_time_bb) > (unsigned long)(I2C_BYTE_TO_BB))
			return 1;
	}

	return 0;
}

static int i2c_xfer_init(struct i2c_regs *i2c_base, uchar chip, uint addr,
			 int alen)
{
	if (i2c_wait_for_bb(i2c_base))
		return 1;

	i2c_setaddress(i2c_base, chip);
	while (alen) {
		alen--;
		/* high byte address going out first */
		writel((addr >> (alen * 8)) & 0xff,
		       &i2c_base->ic_cmd_data);
	}
	return 0;
}

static int i2c_xfer_finish(struct i2c_regs *i2c_base)
{
	ulong start_stop_det = get_timer(0);

	while (1) {
		if ((readl(&i2c_base->ic_raw_intr_stat) & IC_STOP_DET)) {
			readl(&i2c_base->ic_clr_stop_det);
			break;
		} else if (get_timer(start_stop_det) > I2C_STOPDET_TO) {
			break;
		}
	}

	if (i2c_wait_for_bb(i2c_base)) {
		printf("Timed out waiting for bus\n");
		return 1;
	}

	i2c_flush_rxfifo(i2c_base);

	return 0;
}

/*
 * i2c_read - Read from i2c memory
 * @chip:	target i2c address
 * @addr:	address to read from
 * @alen:
 * @buffer:	buffer for read data
 * @len:	no of bytes to be read
 *
 * Read from i2c memory.
 */
static int __dw_i2c_read(struct i2c_regs *i2c_base, u8 dev, uint addr,
			 int alen, u8 *buffer, int len)
{
	unsigned long start_time_rx;

#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
	/*
	 * EEPROM chips that implement "address overflow" are ones
	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
	 * address and the extra bits end up in the "chip address"
	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like
	 * four 256 byte chips.
	 *
	 * Note that we consider the length of the address field to
	 * still be one byte because the extra address bits are
	 * hidden in the chip address.
	 */
	dev |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
	addr &= ~(CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW << (alen * 8));

	debug("%s: fix addr_overflow: dev %02x addr %02x\n", __func__, dev,
	      addr);
#endif

	if (i2c_xfer_init(i2c_base, dev, addr, alen))
		return 1;

	start_time_rx = get_timer(0);
	while (len) {
		if (len == 1)
			writel(IC_CMD | IC_STOP, &i2c_base->ic_cmd_data);
		else
			writel(IC_CMD, &i2c_base->ic_cmd_data);

		if (readl(&i2c_base->ic_status) & IC_STATUS_RFNE) {
			*buffer++ = (uchar)readl(&i2c_base->ic_cmd_data);
			len--;
			start_time_rx = get_timer(0);

		} else if (get_timer(start_time_rx) > I2C_BYTE_TO) {
				return 1;
		}
	}

	return i2c_xfer_finish(i2c_base);
}

/*
 * i2c_write - Write to i2c memory
 * @chip:	target i2c address
 * @addr:	address to read from
 * @alen:
 * @buffer:	buffer for read data
 * @len:	no of bytes to be read
 *
 * Write to i2c memory.
 */
static int __dw_i2c_write(struct i2c_regs *i2c_base, u8 dev, uint addr,
			  int alen, u8 *buffer, int len)
{
	int nb = len;
	unsigned long start_time_tx;

#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
	/*
	 * EEPROM chips that implement "address overflow" are ones
	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
	 * address and the extra bits end up in the "chip address"
	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like
	 * four 256 byte chips.
	 *
	 * Note that we consider the length of the address field to
	 * still be one byte because the extra address bits are
	 * hidden in the chip address.
	 */
	dev |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
	addr &= ~(CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW << (alen * 8));

	debug("%s: fix addr_overflow: dev %02x addr %02x\n", __func__, dev,
	      addr);
#endif

	if (i2c_xfer_init(i2c_base, dev, addr, alen))
		return 1;

	start_time_tx = get_timer(0);
	while (len) {
		if (readl(&i2c_base->ic_status) & IC_STATUS_TFNF) {
			if (--len == 0) {
				writel(*buffer | IC_STOP,
				       &i2c_base->ic_cmd_data);
			} else {
				writel(*buffer, &i2c_base->ic_cmd_data);
			}
			buffer++;
			start_time_tx = get_timer(0);

		} else if (get_timer(start_time_tx) > (nb * I2C_BYTE_TO)) {
				printf("Timed out. i2c write Failed\n");
				return 1;
		}
	}

	return i2c_xfer_finish(i2c_base);
}

/*
 * __dw_i2c_init - Init function
 * @speed:	required i2c speed
 * @slaveaddr:	slave address for the device
 *
 * Initialization function.
 */
static void __dw_i2c_init(struct i2c_regs *i2c_base, int speed, int slaveaddr)
{
	/* Disable i2c */
	dw_i2c_enable(i2c_base, false);

	writel((IC_CON_SD | IC_CON_SPD_FS | IC_CON_MM), &i2c_base->ic_con);
	writel(IC_RX_TL, &i2c_base->ic_rx_tl);
	writel(IC_TX_TL, &i2c_base->ic_tx_tl);
	writel(IC_STOP_DET, &i2c_base->ic_intr_mask);
#ifndef CONFIG_DM_I2C
	__dw_i2c_set_bus_speed(i2c_base, NULL, speed);
	writel(slaveaddr, &i2c_base->ic_sar);
#endif

	/* Enable i2c */
	dw_i2c_enable(i2c_base, true);
}

#ifndef CONFIG_DM_I2C
/*
 * The legacy I2C functions. These need to get removed once
 * all users of this driver are converted to DM.
 */
static struct i2c_regs *i2c_get_base(struct i2c_adapter *adap)
{
	switch (adap->hwadapnr) {
#if CONFIG_SYS_I2C_BUS_MAX >= 4
	case 3:
		return (struct i2c_regs *)CONFIG_SYS_I2C_BASE3;
#endif
#if CONFIG_SYS_I2C_BUS_MAX >= 3
	case 2:
		return (struct i2c_regs *)CONFIG_SYS_I2C_BASE2;
#endif
#if CONFIG_SYS_I2C_BUS_MAX >= 2
	case 1:
		return (struct i2c_regs *)CONFIG_SYS_I2C_BASE1;
#endif
	case 0:
		return (struct i2c_regs *)CONFIG_SYS_I2C_BASE;
	default:
		printf("Wrong I2C-adapter number %d\n", adap->hwadapnr);
	}

	return NULL;
}

static unsigned int dw_i2c_set_bus_speed(struct i2c_adapter *adap,
					 unsigned int speed)
{
	adap->speed = speed;
	return __dw_i2c_set_bus_speed(i2c_get_base(adap), NULL, speed);
}

static void dw_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
{
	__dw_i2c_init(i2c_get_base(adap), speed, slaveaddr);
}

static int dw_i2c_read(struct i2c_adapter *adap, u8 dev, uint addr,
		       int alen, u8 *buffer, int len)
{
	return __dw_i2c_read(i2c_get_base(adap), dev, addr, alen, buffer, len);
}

static int dw_i2c_write(struct i2c_adapter *adap, u8 dev, uint addr,
			int alen, u8 *buffer, int len)
{
	return __dw_i2c_write(i2c_get_base(adap), dev, addr, alen, buffer, len);
}

/* dw_i2c_probe - Probe the i2c chip */
static int dw_i2c_probe(struct i2c_adapter *adap, u8 dev)
{
	struct i2c_regs *i2c_base = i2c_get_base(adap);
	u32 tmp;
	int ret;

	/*
	 * Try to read the first location of the chip.
	 */
	ret = __dw_i2c_read(i2c_base, dev, 0, 1, (uchar *)&tmp, 1);
	if (ret)
		dw_i2c_init(adap, adap->speed, adap->slaveaddr);

	return ret;
}

U_BOOT_I2C_ADAP_COMPLETE(dw_0, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
			 dw_i2c_write, dw_i2c_set_bus_speed,
			 CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE, 0)

#if CONFIG_SYS_I2C_BUS_MAX >= 2
U_BOOT_I2C_ADAP_COMPLETE(dw_1, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
			 dw_i2c_write, dw_i2c_set_bus_speed,
			 CONFIG_SYS_I2C_SPEED1, CONFIG_SYS_I2C_SLAVE1, 1)
#endif

#if CONFIG_SYS_I2C_BUS_MAX >= 3
U_BOOT_I2C_ADAP_COMPLETE(dw_2, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
			 dw_i2c_write, dw_i2c_set_bus_speed,
			 CONFIG_SYS_I2C_SPEED2, CONFIG_SYS_I2C_SLAVE2, 2)
#endif

#if CONFIG_SYS_I2C_BUS_MAX >= 4
U_BOOT_I2C_ADAP_COMPLETE(dw_3, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
			 dw_i2c_write, dw_i2c_set_bus_speed,
			 CONFIG_SYS_I2C_SPEED3, CONFIG_SYS_I2C_SLAVE3, 3)
#endif

#else /* CONFIG_DM_I2C */
/* The DM I2C functions */

static int designware_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
			       int nmsgs)
{
	struct dw_i2c *i2c = dev_get_priv(bus);
	int ret;

	debug("i2c_xfer: %d messages\n", nmsgs);
	for (; nmsgs > 0; nmsgs--, msg++) {
		debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
		if (msg->flags & I2C_M_RD) {
			ret = __dw_i2c_read(i2c->regs, msg->addr, 0, 0,
					    msg->buf, msg->len);
		} else {
			ret = __dw_i2c_write(i2c->regs, msg->addr, 0, 0,
					     msg->buf, msg->len);
		}
		if (ret) {
			debug("i2c_write: error sending\n");
			return -EREMOTEIO;
		}
	}

	return 0;
}

static int designware_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
{
	struct dw_i2c *i2c = dev_get_priv(bus);

	return __dw_i2c_set_bus_speed(i2c->regs, i2c->scl_sda_cfg, speed);
}

static int designware_i2c_probe_chip(struct udevice *bus, uint chip_addr,
				     uint chip_flags)
{
	struct dw_i2c *i2c = dev_get_priv(bus);
	struct i2c_regs *i2c_base = i2c->regs;
	u32 tmp;
	int ret;

	/* Try to read the first location of the chip */
	ret = __dw_i2c_read(i2c_base, chip_addr, 0, 1, (uchar *)&tmp, 1);
	if (ret)
		__dw_i2c_init(i2c_base, 0, 0);

	return ret;
}

static int designware_i2c_probe(struct udevice *bus)
{
	struct dw_i2c *priv = dev_get_priv(bus);

	if (device_is_on_pci_bus(bus)) {
#ifdef CONFIG_DM_PCI
		/* Save base address from PCI BAR */
		priv->regs = (struct i2c_regs *)
			dm_pci_map_bar(bus, PCI_BASE_ADDRESS_0, PCI_REGION_MEM);
#ifdef CONFIG_X86
		/* Use BayTrail specific timing values */
		priv->scl_sda_cfg = &byt_config;
#endif
#endif
	} else {
		priv->regs = (struct i2c_regs *)dev_get_addr_ptr(bus);
	}

	__dw_i2c_init(priv->regs, 0, 0);

	return 0;
}

static int designware_i2c_bind(struct udevice *dev)
{
	static int num_cards;
	char name[20];

	/* Create a unique device name for PCI type devices */
	if (device_is_on_pci_bus(dev)) {
		/*
		 * ToDo:
		 * Setting req_seq in the driver is probably not recommended.
		 * But without a DT alias the number is not configured. And
		 * using this driver is impossible for PCIe I2C devices.
		 * This can be removed, once a better (correct) way for this
		 * is found and implemented.
		 */
		dev->req_seq = num_cards;
		sprintf(name, "i2c_designware#%u", num_cards++);
		device_set_name(dev, name);
	}

	return 0;
}

static const struct dm_i2c_ops designware_i2c_ops = {
	.xfer		= designware_i2c_xfer,
	.probe_chip	= designware_i2c_probe_chip,
	.set_bus_speed	= designware_i2c_set_bus_speed,
};

static const struct udevice_id designware_i2c_ids[] = {
	{ .compatible = "snps,designware-i2c" },
	{ }
};

U_BOOT_DRIVER(i2c_designware) = {
	.name	= "i2c_designware",
	.id	= UCLASS_I2C,
	.of_match = designware_i2c_ids,
	.bind	= designware_i2c_bind,
	.probe	= designware_i2c_probe,
	.priv_auto_alloc_size = sizeof(struct dw_i2c),
	.ops	= &designware_i2c_ops,
};

#ifdef CONFIG_X86
static struct pci_device_id designware_pci_supported[] = {
	/* Intel BayTrail has 7 I2C controller located on the PCI bus */
	{ PCI_VDEVICE(INTEL, 0x0f41) },
	{ PCI_VDEVICE(INTEL, 0x0f42) },
	{ PCI_VDEVICE(INTEL, 0x0f43) },
	{ PCI_VDEVICE(INTEL, 0x0f44) },
	{ PCI_VDEVICE(INTEL, 0x0f45) },
	{ PCI_VDEVICE(INTEL, 0x0f46) },
	{ PCI_VDEVICE(INTEL, 0x0f47) },
	{},
};

U_BOOT_PCI_DEVICE(i2c_designware, designware_pci_supported);
#endif

#endif /* CONFIG_DM_I2C */