summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-adp5588.c
blob: da9781a2ef4adf230fc6704945fc02ac2bca3823 (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
/*
 * GPIO Chip driver for Analog Devices
 * ADP5588/ADP5587 I/O Expander and QWERTY Keypad Controller
 *
 * Copyright 2009-2010 Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/irq.h>

#include <linux/platform_data/adp5588.h>

#define DRV_NAME	"adp5588-gpio"

/*
 * Early pre 4.0 Silicon required to delay readout by at least 25ms,
 * since the Event Counter Register updated 25ms after the interrupt
 * asserted.
 */
#define WA_DELAYED_READOUT_REVID(rev)	((rev) < 4)

struct adp5588_gpio {
	struct i2c_client *client;
	struct gpio_chip gpio_chip;
	struct mutex lock;	/* protect cached dir, dat_out */
	/* protect serialized access to the interrupt controller bus */
	struct mutex irq_lock;
	unsigned gpio_start;
	unsigned irq_base;
	uint8_t dat_out[3];
	uint8_t dir[3];
	uint8_t int_lvl[3];
	uint8_t int_en[3];
	uint8_t irq_mask[3];
	uint8_t irq_stat[3];
	uint8_t int_input_en[3];
	uint8_t int_lvl_cached[3];
};

static int adp5588_gpio_read(struct i2c_client *client, u8 reg)
{
	int ret = i2c_smbus_read_byte_data(client, reg);

	if (ret < 0)
		dev_err(&client->dev, "Read Error\n");

	return ret;
}

static int adp5588_gpio_write(struct i2c_client *client, u8 reg, u8 val)
{
	int ret = i2c_smbus_write_byte_data(client, reg, val);

	if (ret < 0)
		dev_err(&client->dev, "Write Error\n");

	return ret;
}

static int adp5588_gpio_get_value(struct gpio_chip *chip, unsigned off)
{
	struct adp5588_gpio *dev = gpiochip_get_data(chip);
	unsigned bank = ADP5588_BANK(off);
	unsigned bit = ADP5588_BIT(off);
	int val;

	mutex_lock(&dev->lock);

	if (dev->dir[bank] & bit)
		val = dev->dat_out[bank];
	else
		val = adp5588_gpio_read(dev->client, GPIO_DAT_STAT1 + bank);

	mutex_unlock(&dev->lock);

	return !!(val & bit);
}

static void adp5588_gpio_set_value(struct gpio_chip *chip,
				   unsigned off, int val)
{
	unsigned bank, bit;
	struct adp5588_gpio *dev = gpiochip_get_data(chip);

	bank = ADP5588_BANK(off);
	bit = ADP5588_BIT(off);

	mutex_lock(&dev->lock);
	if (val)
		dev->dat_out[bank] |= bit;
	else
		dev->dat_out[bank] &= ~bit;

	adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank,
			   dev->dat_out[bank]);
	mutex_unlock(&dev->lock);
}

static int adp5588_gpio_direction_input(struct gpio_chip *chip, unsigned off)
{
	int ret;
	unsigned bank;
	struct adp5588_gpio *dev = gpiochip_get_data(chip);

	bank = ADP5588_BANK(off);

	mutex_lock(&dev->lock);
	dev->dir[bank] &= ~ADP5588_BIT(off);
	ret = adp5588_gpio_write(dev->client, GPIO_DIR1 + bank, dev->dir[bank]);
	mutex_unlock(&dev->lock);

	return ret;
}

static int adp5588_gpio_direction_output(struct gpio_chip *chip,
					 unsigned off, int val)
{
	int ret;
	unsigned bank, bit;
	struct adp5588_gpio *dev = gpiochip_get_data(chip);

	bank = ADP5588_BANK(off);
	bit = ADP5588_BIT(off);

	mutex_lock(&dev->lock);
	dev->dir[bank] |= bit;

	if (val)
		dev->dat_out[bank] |= bit;
	else
		dev->dat_out[bank] &= ~bit;

	ret = adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank,
				 dev->dat_out[bank]);
	ret |= adp5588_gpio_write(dev->client, GPIO_DIR1 + bank,
				 dev->dir[bank]);
	mutex_unlock(&dev->lock);

	return ret;
}

#ifdef CONFIG_GPIO_ADP5588_IRQ
static int adp5588_gpio_to_irq(struct gpio_chip *chip, unsigned off)
{
	struct adp5588_gpio *dev = gpiochip_get_data(chip);

	return dev->irq_base + off;
}

static void adp5588_irq_bus_lock(struct irq_data *d)
{
	struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);

	mutex_lock(&dev->irq_lock);
}

 /*
  * genirq core code can issue chip->mask/unmask from atomic context.
  * This doesn't work for slow busses where an access needs to sleep.
  * bus_sync_unlock() is therefore called outside the atomic context,
  * syncs the current irq mask state with the slow external controller
  * and unlocks the bus.
  */

static void adp5588_irq_bus_sync_unlock(struct irq_data *d)
{
	struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
	int i;

	for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) {
		if (dev->int_input_en[i]) {
			mutex_lock(&dev->lock);
			dev->dir[i] &= ~dev->int_input_en[i];
			dev->int_input_en[i] = 0;
			adp5588_gpio_write(dev->client, GPIO_DIR1 + i,
					   dev->dir[i]);
			mutex_unlock(&dev->lock);
		}

		if (dev->int_lvl_cached[i] != dev->int_lvl[i]) {
			dev->int_lvl_cached[i] = dev->int_lvl[i];
			adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + i,
					   dev->int_lvl[i]);
		}

		if (dev->int_en[i] ^ dev->irq_mask[i]) {
			dev->int_en[i] = dev->irq_mask[i];
			adp5588_gpio_write(dev->client, GPIO_INT_EN1 + i,
					   dev->int_en[i]);
		}
	}

	mutex_unlock(&dev->irq_lock);
}

static void adp5588_irq_mask(struct irq_data *d)
{
	struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
	unsigned gpio = d->irq - dev->irq_base;

	dev->irq_mask[ADP5588_BANK(gpio)] &= ~ADP5588_BIT(gpio);
}

static void adp5588_irq_unmask(struct irq_data *d)
{
	struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
	unsigned gpio = d->irq - dev->irq_base;

	dev->irq_mask[ADP5588_BANK(gpio)] |= ADP5588_BIT(gpio);
}

static int adp5588_irq_set_type(struct irq_data *d, unsigned int type)
{
	struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
	uint16_t gpio = d->irq - dev->irq_base;
	unsigned bank, bit;

	if ((type & IRQ_TYPE_EDGE_BOTH)) {
		dev_err(&dev->client->dev, "irq %d: unsupported type %d\n",
			d->irq, type);
		return -EINVAL;
	}

	bank = ADP5588_BANK(gpio);
	bit = ADP5588_BIT(gpio);

	if (type & IRQ_TYPE_LEVEL_HIGH)
		dev->int_lvl[bank] |= bit;
	else if (type & IRQ_TYPE_LEVEL_LOW)
		dev->int_lvl[bank] &= ~bit;
	else
		return -EINVAL;

	dev->int_input_en[bank] |= bit;

	return 0;
}

static struct irq_chip adp5588_irq_chip = {
	.name			= "adp5588",
	.irq_mask		= adp5588_irq_mask,
	.irq_unmask		= adp5588_irq_unmask,
	.irq_bus_lock		= adp5588_irq_bus_lock,
	.irq_bus_sync_unlock	= adp5588_irq_bus_sync_unlock,
	.irq_set_type		= adp5588_irq_set_type,
};

static int adp5588_gpio_read_intstat(struct i2c_client *client, u8 *buf)
{
	int ret = i2c_smbus_read_i2c_block_data(client, GPIO_INT_STAT1, 3, buf);

	if (ret < 0)
		dev_err(&client->dev, "Read INT_STAT Error\n");

	return ret;
}

static irqreturn_t adp5588_irq_handler(int irq, void *devid)
{
	struct adp5588_gpio *dev = devid;
	unsigned status, bank, bit, pending;
	int ret;
	status = adp5588_gpio_read(dev->client, INT_STAT);

	if (status & ADP5588_GPI_INT) {
		ret = adp5588_gpio_read_intstat(dev->client, dev->irq_stat);
		if (ret < 0)
			memset(dev->irq_stat, 0, ARRAY_SIZE(dev->irq_stat));

		for (bank = 0, bit = 0; bank <= ADP5588_BANK(ADP5588_MAXGPIO);
			bank++, bit = 0) {
			pending = dev->irq_stat[bank] & dev->irq_mask[bank];

			while (pending) {
				if (pending & (1 << bit)) {
					handle_nested_irq(dev->irq_base +
							  (bank << 3) + bit);
					pending &= ~(1 << bit);

				}
				bit++;
			}
		}
	}

	adp5588_gpio_write(dev->client, INT_STAT, status); /* Status is W1C */

	return IRQ_HANDLED;
}

static int adp5588_irq_setup(struct adp5588_gpio *dev)
{
	struct i2c_client *client = dev->client;
	struct adp5588_gpio_platform_data *pdata =
			dev_get_platdata(&client->dev);
	unsigned gpio;
	int ret;

	adp5588_gpio_write(client, CFG, ADP5588_AUTO_INC);
	adp5588_gpio_write(client, INT_STAT, -1); /* status is W1C */
	adp5588_gpio_read_intstat(client, dev->irq_stat); /* read to clear */

	dev->irq_base = pdata->irq_base;
	mutex_init(&dev->irq_lock);

	for (gpio = 0; gpio < dev->gpio_chip.ngpio; gpio++) {
		int irq = gpio + dev->irq_base;
		irq_set_chip_data(irq, dev);
		irq_set_chip_and_handler(irq, &adp5588_irq_chip,
					 handle_level_irq);
		irq_set_nested_thread(irq, 1);
		irq_modify_status(irq, IRQ_NOREQUEST, IRQ_NOPROBE);
	}

	ret = request_threaded_irq(client->irq,
				   NULL,
				   adp5588_irq_handler,
				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
				   dev_name(&client->dev), dev);
	if (ret) {
		dev_err(&client->dev, "failed to request irq %d\n",
			client->irq);
		goto out;
	}

	dev->gpio_chip.to_irq = adp5588_gpio_to_irq;
	adp5588_gpio_write(client, CFG,
		ADP5588_AUTO_INC | ADP5588_INT_CFG | ADP5588_GPI_INT);

	return 0;

out:
	dev->irq_base = 0;
	return ret;
}

static void adp5588_irq_teardown(struct adp5588_gpio *dev)
{
	if (dev->irq_base)
		free_irq(dev->client->irq, dev);
}

#else
static int adp5588_irq_setup(struct adp5588_gpio *dev)
{
	struct i2c_client *client = dev->client;
	dev_warn(&client->dev, "interrupt support not compiled in\n");

	return 0;
}

static void adp5588_irq_teardown(struct adp5588_gpio *dev)
{
}
#endif /* CONFIG_GPIO_ADP5588_IRQ */

static int adp5588_gpio_probe(struct i2c_client *client,
					const struct i2c_device_id *id)
{
	struct adp5588_gpio_platform_data *pdata =
			dev_get_platdata(&client->dev);
	struct adp5588_gpio *dev;
	struct gpio_chip *gc;
	int ret, i, revid;

	if (!pdata) {
		dev_err(&client->dev, "missing platform data\n");
		return -ENODEV;
	}

	if (!i2c_check_functionality(client->adapter,
					I2C_FUNC_SMBUS_BYTE_DATA)) {
		dev_err(&client->dev, "SMBUS Byte Data not Supported\n");
		return -EIO;
	}

	dev = devm_kzalloc(&client->dev, sizeof(*dev), GFP_KERNEL);
	if (!dev)
		return -ENOMEM;

	dev->client = client;

	gc = &dev->gpio_chip;
	gc->direction_input = adp5588_gpio_direction_input;
	gc->direction_output = adp5588_gpio_direction_output;
	gc->get = adp5588_gpio_get_value;
	gc->set = adp5588_gpio_set_value;
	gc->can_sleep = true;

	gc->base = pdata->gpio_start;
	gc->ngpio = ADP5588_MAXGPIO;
	gc->label = client->name;
	gc->owner = THIS_MODULE;
	gc->names = pdata->names;

	mutex_init(&dev->lock);

	ret = adp5588_gpio_read(dev->client, DEV_ID);
	if (ret < 0)
		goto err;

	revid = ret & ADP5588_DEVICE_ID_MASK;

	for (i = 0, ret = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) {
		dev->dat_out[i] = adp5588_gpio_read(client, GPIO_DAT_OUT1 + i);
		dev->dir[i] = adp5588_gpio_read(client, GPIO_DIR1 + i);
		ret |= adp5588_gpio_write(client, KP_GPIO1 + i, 0);
		ret |= adp5588_gpio_write(client, GPIO_PULL1 + i,
				(pdata->pullup_dis_mask >> (8 * i)) & 0xFF);
		ret |= adp5588_gpio_write(client, GPIO_INT_EN1 + i, 0);
		if (ret)
			goto err;
	}

	if (pdata->irq_base) {
		if (WA_DELAYED_READOUT_REVID(revid)) {
			dev_warn(&client->dev, "GPIO int not supported\n");
		} else {
			ret = adp5588_irq_setup(dev);
			if (ret)
				goto err;
		}
	}

	ret = devm_gpiochip_add_data(&client->dev, &dev->gpio_chip, dev);
	if (ret)
		goto err_irq;

	dev_info(&client->dev, "IRQ Base: %d Rev.: %d\n",
			pdata->irq_base, revid);

	if (pdata->setup) {
		ret = pdata->setup(client, gc->base, gc->ngpio, pdata->context);
		if (ret < 0)
			dev_warn(&client->dev, "setup failed, %d\n", ret);
	}

	i2c_set_clientdata(client, dev);

	return 0;

err_irq:
	adp5588_irq_teardown(dev);
err:
	return ret;
}

static int adp5588_gpio_remove(struct i2c_client *client)
{
	struct adp5588_gpio_platform_data *pdata =
			dev_get_platdata(&client->dev);
	struct adp5588_gpio *dev = i2c_get_clientdata(client);
	int ret;

	if (pdata->teardown) {
		ret = pdata->teardown(client,
				      dev->gpio_chip.base, dev->gpio_chip.ngpio,
				      pdata->context);
		if (ret < 0) {
			dev_err(&client->dev, "teardown failed %d\n", ret);
			return ret;
		}
	}

	if (dev->irq_base)
		free_irq(dev->client->irq, dev);

	return 0;
}

static const struct i2c_device_id adp5588_gpio_id[] = {
	{DRV_NAME, 0},
	{}
};

MODULE_DEVICE_TABLE(i2c, adp5588_gpio_id);

static struct i2c_driver adp5588_gpio_driver = {
	.driver = {
		   .name = DRV_NAME,
		   },
	.probe = adp5588_gpio_probe,
	.remove = adp5588_gpio_remove,
	.id_table = adp5588_gpio_id,
};

module_i2c_driver(adp5588_gpio_driver);

MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("GPIO ADP5588 Driver");
MODULE_LICENSE("GPL");