aboutsummaryrefslogtreecommitdiff
path: root/drivers/mfd/stmfx.c
blob: 857991cb3cbb8b5a890514a24d0b3e7d2e0467c0 (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
// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for STMicroelectronics Multi-Function eXpander (STMFX) core
 *
 * Copyright (C) 2019 STMicroelectronics
 * Author(s): Amelie Delaunay <amelie.delaunay@st.com>.
 */
#include <linux/bitfield.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/mfd/core.h>
#include <linux/mfd/stmfx.h>
#include <linux/module.h>
#include <linux/regulator/consumer.h>

static bool stmfx_reg_volatile(struct device *dev, unsigned int reg)
{
	switch (reg) {
	case STMFX_REG_SYS_CTRL:
	case STMFX_REG_IRQ_SRC_EN:
	case STMFX_REG_IRQ_PENDING:
	case STMFX_REG_IRQ_GPI_PENDING1:
	case STMFX_REG_IRQ_GPI_PENDING2:
	case STMFX_REG_IRQ_GPI_PENDING3:
	case STMFX_REG_GPIO_STATE1:
	case STMFX_REG_GPIO_STATE2:
	case STMFX_REG_GPIO_STATE3:
	case STMFX_REG_IRQ_GPI_SRC1:
	case STMFX_REG_IRQ_GPI_SRC2:
	case STMFX_REG_IRQ_GPI_SRC3:
	case STMFX_REG_GPO_SET1:
	case STMFX_REG_GPO_SET2:
	case STMFX_REG_GPO_SET3:
	case STMFX_REG_GPO_CLR1:
	case STMFX_REG_GPO_CLR2:
	case STMFX_REG_GPO_CLR3:
		return true;
	default:
		return false;
	}
}

static bool stmfx_reg_writeable(struct device *dev, unsigned int reg)
{
	return (reg >= STMFX_REG_SYS_CTRL);
}

static const struct regmap_config stmfx_regmap_config = {
	.reg_bits	= 8,
	.reg_stride	= 1,
	.val_bits	= 8,
	.max_register	= STMFX_REG_MAX,
	.volatile_reg	= stmfx_reg_volatile,
	.writeable_reg	= stmfx_reg_writeable,
	.cache_type	= REGCACHE_RBTREE,
};

static const struct resource stmfx_pinctrl_resources[] = {
	DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_GPIO),
};

static const struct resource stmfx_idd_resources[] = {
	DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_IDD),
	DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_ERROR),
};

static const struct resource stmfx_ts_resources[] = {
	DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_DET),
	DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_NE),
	DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_TH),
	DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_FULL),
	DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_OVF),
};

static struct mfd_cell stmfx_cells[] = {
	{
		.of_compatible = "st,stmfx-0300-pinctrl",
		.name = "stmfx-pinctrl",
		.resources = stmfx_pinctrl_resources,
		.num_resources = ARRAY_SIZE(stmfx_pinctrl_resources),
	},
	{
		.of_compatible = "st,stmfx-0300-idd",
		.name = "stmfx-idd",
		.resources = stmfx_idd_resources,
		.num_resources = ARRAY_SIZE(stmfx_idd_resources),
	},
	{
		.of_compatible = "st,stmfx-0300-ts",
		.name = "stmfx-ts",
		.resources = stmfx_ts_resources,
		.num_resources = ARRAY_SIZE(stmfx_ts_resources),
	},
};

static u8 stmfx_func_to_mask(u32 func)
{
	u8 mask = 0;

	if (func & STMFX_FUNC_GPIO)
		mask |= STMFX_REG_SYS_CTRL_GPIO_EN;

	if ((func & STMFX_FUNC_ALTGPIO_LOW) || (func & STMFX_FUNC_ALTGPIO_HIGH))
		mask |= STMFX_REG_SYS_CTRL_ALTGPIO_EN;

	if (func & STMFX_FUNC_TS)
		mask |= STMFX_REG_SYS_CTRL_TS_EN;

	if (func & STMFX_FUNC_IDD)
		mask |= STMFX_REG_SYS_CTRL_IDD_EN;

	return mask;
}

int stmfx_function_enable(struct stmfx *stmfx, u32 func)
{
	u32 sys_ctrl;
	u8 mask;
	int ret;

	ret = regmap_read(stmfx->map, STMFX_REG_SYS_CTRL, &sys_ctrl);
	if (ret)
		return ret;

	/*
	 * IDD and TS have priority in STMFX FW, so if IDD and TS are enabled,
	 * ALTGPIO function is disabled by STMFX FW. If IDD or TS is enabled,
	 * the number of aGPIO available decreases. To avoid GPIO management
	 * disturbance, abort IDD or TS function enable in this case.
	 */
	if (((func & STMFX_FUNC_IDD) || (func & STMFX_FUNC_TS)) &&
	    (sys_ctrl & STMFX_REG_SYS_CTRL_ALTGPIO_EN)) {
		dev_err(stmfx->dev, "ALTGPIO function already enabled\n");
		return -EBUSY;
	}

	/* If TS is enabled, aGPIO[3:0] cannot be used */
	if ((func & STMFX_FUNC_ALTGPIO_LOW) &&
	    (sys_ctrl & STMFX_REG_SYS_CTRL_TS_EN)) {
		dev_err(stmfx->dev, "TS in use, aGPIO[3:0] unavailable\n");
		return -EBUSY;
	}

	/* If IDD is enabled, aGPIO[7:4] cannot be used */
	if ((func & STMFX_FUNC_ALTGPIO_HIGH) &&
	    (sys_ctrl & STMFX_REG_SYS_CTRL_IDD_EN)) {
		dev_err(stmfx->dev, "IDD in use, aGPIO[7:4] unavailable\n");
		return -EBUSY;
	}

	mask = stmfx_func_to_mask(func);

	return regmap_update_bits(stmfx->map, STMFX_REG_SYS_CTRL, mask, mask);
}
EXPORT_SYMBOL_GPL(stmfx_function_enable);

int stmfx_function_disable(struct stmfx *stmfx, u32 func)
{
	u8 mask = stmfx_func_to_mask(func);

	return regmap_update_bits(stmfx->map, STMFX_REG_SYS_CTRL, mask, 0);
}
EXPORT_SYMBOL_GPL(stmfx_function_disable);

static void stmfx_irq_bus_lock(struct irq_data *data)
{
	struct stmfx *stmfx = irq_data_get_irq_chip_data(data);

	mutex_lock(&stmfx->lock);
}

static void stmfx_irq_bus_sync_unlock(struct irq_data *data)
{
	struct stmfx *stmfx = irq_data_get_irq_chip_data(data);

	regmap_write(stmfx->map, STMFX_REG_IRQ_SRC_EN, stmfx->irq_src);

	mutex_unlock(&stmfx->lock);
}

static void stmfx_irq_mask(struct irq_data *data)
{
	struct stmfx *stmfx = irq_data_get_irq_chip_data(data);

	stmfx->irq_src &= ~BIT(data->hwirq % 8);
}

static void stmfx_irq_unmask(struct irq_data *data)
{
	struct stmfx *stmfx = irq_data_get_irq_chip_data(data);

	stmfx->irq_src |= BIT(data->hwirq % 8);
}

static struct irq_chip stmfx_irq_chip = {
	.name			= "stmfx-core",
	.irq_bus_lock		= stmfx_irq_bus_lock,
	.irq_bus_sync_unlock	= stmfx_irq_bus_sync_unlock,
	.irq_mask		= stmfx_irq_mask,
	.irq_unmask		= stmfx_irq_unmask,
};

static irqreturn_t stmfx_irq_handler(int irq, void *data)
{
	struct stmfx *stmfx = data;
	unsigned long bits;
	u32 pending, ack;
	int n, ret;

	ret = regmap_read(stmfx->map, STMFX_REG_IRQ_PENDING, &pending);
	if (ret)
		return IRQ_NONE;

	/*
	 * There is no ACK for GPIO, MFX_REG_IRQ_PENDING_GPIO is a logical OR
	 * of MFX_REG_IRQ_GPI _PENDING1/_PENDING2/_PENDING3
	 */
	ack = pending & ~BIT(STMFX_REG_IRQ_SRC_EN_GPIO);
	if (ack) {
		ret = regmap_write(stmfx->map, STMFX_REG_IRQ_ACK, ack);
		if (ret)
			return IRQ_NONE;
	}

	bits = pending;
	for_each_set_bit(n, &bits, STMFX_REG_IRQ_SRC_MAX)
		handle_nested_irq(irq_find_mapping(stmfx->irq_domain, n));

	return IRQ_HANDLED;
}

static int stmfx_irq_map(struct irq_domain *d, unsigned int virq,
			 irq_hw_number_t hwirq)
{
	irq_set_chip_data(virq, d->host_data);
	irq_set_chip_and_handler(virq, &stmfx_irq_chip, handle_simple_irq);
	irq_set_nested_thread(virq, 1);
	irq_set_noprobe(virq);

	return 0;
}

static void stmfx_irq_unmap(struct irq_domain *d, unsigned int virq)
{
	irq_set_chip_and_handler(virq, NULL, NULL);
	irq_set_chip_data(virq, NULL);
}

static const struct irq_domain_ops stmfx_irq_ops = {
	.map	= stmfx_irq_map,
	.unmap	= stmfx_irq_unmap,
};

static void stmfx_irq_exit(struct i2c_client *client)
{
	struct stmfx *stmfx = i2c_get_clientdata(client);
	int hwirq;

	for (hwirq = 0; hwirq < STMFX_REG_IRQ_SRC_MAX; hwirq++)
		irq_dispose_mapping(irq_find_mapping(stmfx->irq_domain, hwirq));

	irq_domain_remove(stmfx->irq_domain);
}

static int stmfx_irq_init(struct i2c_client *client)
{
	struct stmfx *stmfx = i2c_get_clientdata(client);
	u32 irqoutpin = 0, irqtrigger;
	int ret;

	stmfx->irq_domain = irq_domain_add_simple(stmfx->dev->of_node,
						  STMFX_REG_IRQ_SRC_MAX, 0,
						  &stmfx_irq_ops, stmfx);
	if (!stmfx->irq_domain) {
		dev_err(stmfx->dev, "Failed to create IRQ domain\n");
		return -EINVAL;
	}

	if (!of_property_read_bool(stmfx->dev->of_node, "drive-open-drain"))
		irqoutpin |= STMFX_REG_IRQ_OUT_PIN_TYPE;

	irqtrigger = irq_get_trigger_type(client->irq);
	if ((irqtrigger & IRQ_TYPE_EDGE_RISING) ||
	    (irqtrigger & IRQ_TYPE_LEVEL_HIGH))
		irqoutpin |= STMFX_REG_IRQ_OUT_PIN_POL;

	ret = regmap_write(stmfx->map, STMFX_REG_IRQ_OUT_PIN, irqoutpin);
	if (ret)
		return ret;

	ret = devm_request_threaded_irq(stmfx->dev, client->irq,
					NULL, stmfx_irq_handler,
					irqtrigger | IRQF_ONESHOT,
					"stmfx", stmfx);
	if (ret)
		stmfx_irq_exit(client);

	return ret;
}

static int stmfx_chip_reset(struct stmfx *stmfx)
{
	int ret;

	ret = regmap_write(stmfx->map, STMFX_REG_SYS_CTRL,
			   STMFX_REG_SYS_CTRL_SWRST);
	if (ret)
		return ret;

	msleep(STMFX_BOOT_TIME_MS);

	return ret;
}

static int stmfx_chip_init(struct i2c_client *client)
{
	struct stmfx *stmfx = i2c_get_clientdata(client);
	u32 id;
	u8 version[2];
	int ret;

	stmfx->vdd = devm_regulator_get_optional(&client->dev, "vdd");
	ret = PTR_ERR_OR_ZERO(stmfx->vdd);
	if (ret == -ENODEV) {
		stmfx->vdd = NULL;
	} else if (ret == -EPROBE_DEFER) {
		return ret;
	} else if (ret) {
		dev_err(&client->dev, "Failed to get VDD regulator: %d\n", ret);
		return ret;
	}

	if (stmfx->vdd) {
		ret = regulator_enable(stmfx->vdd);
		if (ret) {
			dev_err(&client->dev, "VDD enable failed: %d\n", ret);
			return ret;
		}
	}

	ret = regmap_read(stmfx->map, STMFX_REG_CHIP_ID, &id);
	if (ret) {
		dev_err(&client->dev, "Error reading chip ID: %d\n", ret);
		goto err;
	}

	/*
	 * Check that ID is the complement of the I2C address:
	 * STMFX I2C address follows the 7-bit format (MSB), that's why
	 * client->addr is shifted.
	 *
	 * STMFX_I2C_ADDR|       STMFX         |        Linux
	 *   input pin   | I2C device address  | I2C device address
	 *---------------------------------------------------------
	 *       0       | b: 1000 010x h:0x84 |       0x42
	 *       1       | b: 1000 011x h:0x86 |       0x43
	 */
	if (FIELD_GET(STMFX_REG_CHIP_ID_MASK, ~id) != (client->addr << 1)) {
		dev_err(&client->dev, "Unknown chip ID: %#x\n", id);
		ret = -EINVAL;
		goto err;
	}

	ret = regmap_bulk_read(stmfx->map, STMFX_REG_FW_VERSION_MSB,
			       version, ARRAY_SIZE(version));
	if (ret) {
		dev_err(&client->dev, "Error reading FW version: %d\n", ret);
		goto err;
	}

	dev_info(&client->dev, "STMFX id: %#x, fw version: %x.%02x\n",
		 id, version[0], version[1]);

	ret = stmfx_chip_reset(stmfx);
	if (ret) {
		dev_err(&client->dev, "Failed to reset chip: %d\n", ret);
		goto err;
	}

	return 0;

err:
	if (stmfx->vdd)
		return regulator_disable(stmfx->vdd);

	return ret;
}

static int stmfx_chip_exit(struct i2c_client *client)
{
	struct stmfx *stmfx = i2c_get_clientdata(client);

	regmap_write(stmfx->map, STMFX_REG_IRQ_SRC_EN, 0);
	regmap_write(stmfx->map, STMFX_REG_SYS_CTRL, 0);

	if (stmfx->vdd)
		return regulator_disable(stmfx->vdd);

	return 0;
}

static int stmfx_probe(struct i2c_client *client,
		       const struct i2c_device_id *id)
{
	struct device *dev = &client->dev;
	struct stmfx *stmfx;
	int ret;

	stmfx = devm_kzalloc(dev, sizeof(*stmfx), GFP_KERNEL);
	if (!stmfx)
		return -ENOMEM;

	i2c_set_clientdata(client, stmfx);

	stmfx->dev = dev;

	stmfx->map = devm_regmap_init_i2c(client, &stmfx_regmap_config);
	if (IS_ERR(stmfx->map)) {
		ret = PTR_ERR(stmfx->map);
		dev_err(dev, "Failed to allocate register map: %d\n", ret);
		return ret;
	}

	mutex_init(&stmfx->lock);

	ret = stmfx_chip_init(client);
	if (ret) {
		if (ret == -ETIMEDOUT)
			return -EPROBE_DEFER;
		return ret;
	}

	if (client->irq < 0) {
		dev_err(dev, "Failed to get IRQ: %d\n", client->irq);
		ret = client->irq;
		goto err_chip_exit;
	}

	ret = stmfx_irq_init(client);
	if (ret)
		goto err_chip_exit;

	ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
				   stmfx_cells, ARRAY_SIZE(stmfx_cells), NULL,
				   0, stmfx->irq_domain);
	if (ret)
		goto err_irq_exit;

	return 0;

err_irq_exit:
	stmfx_irq_exit(client);
err_chip_exit:
	stmfx_chip_exit(client);

	return ret;
}

static int stmfx_remove(struct i2c_client *client)
{
	stmfx_irq_exit(client);

	return stmfx_chip_exit(client);
}

#ifdef CONFIG_PM_SLEEP
static int stmfx_suspend(struct device *dev)
{
	struct stmfx *stmfx = dev_get_drvdata(dev);
	int ret;

	ret = regmap_raw_read(stmfx->map, STMFX_REG_SYS_CTRL,
			      &stmfx->bkp_sysctrl, sizeof(stmfx->bkp_sysctrl));
	if (ret)
		return ret;

	ret = regmap_raw_read(stmfx->map, STMFX_REG_IRQ_OUT_PIN,
			      &stmfx->bkp_irqoutpin,
			      sizeof(stmfx->bkp_irqoutpin));
	if (ret)
		return ret;

	if (stmfx->vdd)
		return regulator_disable(stmfx->vdd);

	return 0;
}

static int stmfx_resume(struct device *dev)
{
	struct stmfx *stmfx = dev_get_drvdata(dev);
	int ret;

	if (stmfx->vdd) {
		ret = regulator_enable(stmfx->vdd);
		if (ret) {
			dev_err(stmfx->dev,
				"VDD enable failed: %d\n", ret);
			return ret;
		}
	}

	ret = regmap_raw_write(stmfx->map, STMFX_REG_SYS_CTRL,
			       &stmfx->bkp_sysctrl, sizeof(stmfx->bkp_sysctrl));
	if (ret)
		return ret;

	ret = regmap_raw_write(stmfx->map, STMFX_REG_IRQ_OUT_PIN,
			       &stmfx->bkp_irqoutpin,
			       sizeof(stmfx->bkp_irqoutpin));
	if (ret)
		return ret;

	ret = regmap_raw_write(stmfx->map, STMFX_REG_IRQ_SRC_EN,
			       &stmfx->irq_src, sizeof(stmfx->irq_src));
	if (ret)
		return ret;

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(stmfx_dev_pm_ops, stmfx_suspend, stmfx_resume);

static const struct of_device_id stmfx_of_match[] = {
	{ .compatible = "st,stmfx-0300", },
	{},
};
MODULE_DEVICE_TABLE(of, stmfx_of_match);

static struct i2c_driver stmfx_driver = {
	.driver = {
		.name = "stmfx-core",
		.of_match_table = of_match_ptr(stmfx_of_match),
		.pm = &stmfx_dev_pm_ops,
	},
	.probe = stmfx_probe,
	.remove = stmfx_remove,
};
module_i2c_driver(stmfx_driver);

MODULE_DESCRIPTION("STMFX core driver");
MODULE_AUTHOR("Amelie Delaunay <amelie.delaunay@st.com>");
MODULE_LICENSE("GPL v2");