summaryrefslogtreecommitdiff
path: root/drivers/leds/leds-an30259a.c
blob: e072ee5409f7e0bc1c52caeb263a411dadc3ba4c (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
// SPDX-License-Identifier: GPL-2.0+
//
// Driver for Panasonic AN30259A 3-channel LED driver
//
// Copyright (c) 2018 Simon Shields <simon@lineageos.org>
//
// Datasheet:
// https://www.alliedelec.com/m/d/a9d2b3ee87c2d1a535a41dd747b1c247.pdf

#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/regmap.h>

#define AN30259A_MAX_LEDS 3

#define AN30259A_REG_SRESET 0x00
#define AN30259A_LED_SRESET BIT(0)

/* LED power registers */
#define AN30259A_REG_LED_ON 0x01
#define AN30259A_LED_EN(x) BIT((x) - 1)
#define AN30259A_LED_SLOPE(x) BIT(((x) - 1) + 4)

#define AN30259A_REG_LEDCC(x) (0x03 + ((x) - 1))

/* slope control registers */
#define AN30259A_REG_SLOPE(x) (0x06 + ((x) - 1))
#define AN30259A_LED_SLOPETIME1(x) (x)
#define AN30259A_LED_SLOPETIME2(x) ((x) << 4)

#define AN30259A_REG_LEDCNT1(x) (0x09 + (4 * ((x) - 1)))
#define AN30259A_LED_DUTYMAX(x) ((x) << 4)
#define AN30259A_LED_DUTYMID(x) (x)

#define AN30259A_REG_LEDCNT2(x) (0x0A + (4 * ((x) - 1)))
#define AN30259A_LED_DELAY(x) ((x) << 4)
#define AN30259A_LED_DUTYMIN(x) (x)

/* detention time control (length of each slope step) */
#define AN30259A_REG_LEDCNT3(x) (0x0B + (4 * ((x) - 1)))
#define AN30259A_LED_DT1(x) (x)
#define AN30259A_LED_DT2(x) ((x) << 4)

#define AN30259A_REG_LEDCNT4(x) (0x0C + (4 * ((x) - 1)))
#define AN30259A_LED_DT3(x) (x)
#define AN30259A_LED_DT4(x) ((x) << 4)

#define AN30259A_REG_MAX 0x14

#define AN30259A_BLINK_MAX_TIME 7500 /* ms */
#define AN30259A_SLOPE_RESOLUTION 500 /* ms */

#define AN30259A_NAME "an30259a"

#define STATE_OFF 0
#define STATE_KEEP 1
#define STATE_ON 2

struct an30259a;

struct an30259a_led {
	struct an30259a *chip;
	struct fwnode_handle *fwnode;
	struct led_classdev cdev;
	u32 num;
	u32 default_state;
	bool sloping;
};

struct an30259a {
	struct mutex mutex; /* held when writing to registers */
	struct i2c_client *client;
	struct an30259a_led leds[AN30259A_MAX_LEDS];
	struct regmap *regmap;
	int num_leds;
};

static int an30259a_brightness_set(struct led_classdev *cdev,
				   enum led_brightness brightness)
{
	struct an30259a_led *led;
	int ret;
	unsigned int led_on;

	led = container_of(cdev, struct an30259a_led, cdev);
	mutex_lock(&led->chip->mutex);

	ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);
	if (ret)
		goto error;

	switch (brightness) {
	case LED_OFF:
		led_on &= ~AN30259A_LED_EN(led->num);
		led_on &= ~AN30259A_LED_SLOPE(led->num);
		led->sloping = false;
		break;
	default:
		led_on |= AN30259A_LED_EN(led->num);
		if (led->sloping)
			led_on |= AN30259A_LED_SLOPE(led->num);
		ret = regmap_write(led->chip->regmap,
				   AN30259A_REG_LEDCNT1(led->num),
				   AN30259A_LED_DUTYMAX(0xf) |
				   AN30259A_LED_DUTYMID(0xf));
		if (ret)
			goto error;
		break;
	}

	ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);
	if (ret)
		goto error;

	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCC(led->num),
			   brightness);

error:
	mutex_unlock(&led->chip->mutex);

	return ret;
}

static int an30259a_blink_set(struct led_classdev *cdev,
			      unsigned long *delay_off, unsigned long *delay_on)
{
	struct an30259a_led *led;
	int ret, num;
	unsigned int led_on;
	unsigned long off = *delay_off, on = *delay_on;

	led = container_of(cdev, struct an30259a_led, cdev);

	mutex_lock(&led->chip->mutex);
	num = led->num;

	/* slope time can only be a multiple of 500ms. */
	if (off % AN30259A_SLOPE_RESOLUTION || on % AN30259A_SLOPE_RESOLUTION) {
		ret = -EINVAL;
		goto error;
	}

	/* up to a maximum of 7500ms. */
	if (off > AN30259A_BLINK_MAX_TIME || on > AN30259A_BLINK_MAX_TIME) {
		ret = -EINVAL;
		goto error;
	}

	/* if no blink specified, default to 1 Hz. */
	if (!off && !on) {
		*delay_off = off = 500;
		*delay_on = on = 500;
	}

	/* convert into values the HW will understand. */
	off /= AN30259A_SLOPE_RESOLUTION;
	on /= AN30259A_SLOPE_RESOLUTION;

	/* duty min should be zero (=off), delay should be zero. */
	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT2(num),
			   AN30259A_LED_DELAY(0) | AN30259A_LED_DUTYMIN(0));
	if (ret)
		goto error;

	/* reset detention time (no "breathing" effect). */
	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT3(num),
			   AN30259A_LED_DT1(0) | AN30259A_LED_DT2(0));
	if (ret)
		goto error;
	ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT4(num),
			   AN30259A_LED_DT3(0) | AN30259A_LED_DT4(0));
	if (ret)
		goto error;

	/* slope time controls on/off cycle length. */
	ret = regmap_write(led->chip->regmap, AN30259A_REG_SLOPE(num),
			   AN30259A_LED_SLOPETIME1(off) |
			   AN30259A_LED_SLOPETIME2(on));
	if (ret)
		goto error;

	/* Finally, enable slope mode. */
	ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on);
	if (ret)
		goto error;

	led_on |= AN30259A_LED_SLOPE(num) | AN30259A_LED_EN(led->num);

	ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on);

	if (!ret)
		led->sloping = true;
error:
	mutex_unlock(&led->chip->mutex);

	return ret;
}

static int an30259a_dt_init(struct i2c_client *client,
			    struct an30259a *chip)
{
	struct device_node *np = dev_of_node(&client->dev), *child;
	int count, ret;
	int i = 0;
	const char *str;
	struct an30259a_led *led;

	count = of_get_available_child_count(np);
	if (!count || count > AN30259A_MAX_LEDS)
		return -EINVAL;

	for_each_available_child_of_node(np, child) {
		u32 source;

		ret = of_property_read_u32(child, "reg", &source);
		if (ret != 0 || !source || source > AN30259A_MAX_LEDS) {
			dev_err(&client->dev, "Couldn't read LED address: %d\n",
				ret);
			count--;
			continue;
		}

		led = &chip->leds[i];

		led->num = source;
		led->chip = chip;
		led->fwnode = of_fwnode_handle(child);

		if (!of_property_read_string(child, "default-state", &str)) {
			if (!strcmp(str, "on"))
				led->default_state = STATE_ON;
			else if (!strcmp(str, "keep"))
				led->default_state = STATE_KEEP;
			else
				led->default_state = STATE_OFF;
		}

		i++;
	}

	if (!count)
		return -EINVAL;

	chip->num_leds = i;

	return 0;
}

static const struct regmap_config an30259a_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = AN30259A_REG_MAX,
};

static void an30259a_init_default_state(struct an30259a_led *led)
{
	struct an30259a *chip = led->chip;
	int led_on, err;

	switch (led->default_state) {
	case STATE_ON:
		led->cdev.brightness = LED_FULL;
		break;
	case STATE_KEEP:
		err = regmap_read(chip->regmap, AN30259A_REG_LED_ON, &led_on);
		if (err)
			break;

		if (!(led_on & AN30259A_LED_EN(led->num))) {
			led->cdev.brightness = LED_OFF;
			break;
		}
		regmap_read(chip->regmap, AN30259A_REG_LEDCC(led->num),
			    &led->cdev.brightness);
		break;
	default:
		led->cdev.brightness = LED_OFF;
	}

	an30259a_brightness_set(&led->cdev, led->cdev.brightness);
}

static int an30259a_probe(struct i2c_client *client)
{
	struct an30259a *chip;
	int i, err;

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

	err = an30259a_dt_init(client, chip);
	if (err < 0)
		return err;

	mutex_init(&chip->mutex);
	chip->client = client;
	i2c_set_clientdata(client, chip);

	chip->regmap = devm_regmap_init_i2c(client, &an30259a_regmap_config);

	if (IS_ERR(chip->regmap)) {
		err = PTR_ERR(chip->regmap);
		dev_err(&client->dev, "Failed to allocate register map: %d\n",
			err);
		goto exit;
	}

	for (i = 0; i < chip->num_leds; i++) {
		struct led_init_data init_data = {};

		an30259a_init_default_state(&chip->leds[i]);
		chip->leds[i].cdev.brightness_set_blocking =
			an30259a_brightness_set;
		chip->leds[i].cdev.blink_set = an30259a_blink_set;

		init_data.fwnode = chip->leds[i].fwnode;
		init_data.devicename = AN30259A_NAME;
		init_data.default_label = ":";

		err = devm_led_classdev_register_ext(&client->dev,
						 &chip->leds[i].cdev,
						 &init_data);
		if (err < 0)
			goto exit;
	}
	return 0;

exit:
	mutex_destroy(&chip->mutex);
	return err;
}

static void an30259a_remove(struct i2c_client *client)
{
	struct an30259a *chip = i2c_get_clientdata(client);

	mutex_destroy(&chip->mutex);
}

static const struct of_device_id an30259a_match_table[] = {
	{ .compatible = "panasonic,an30259a", },
	{ /* sentinel */ },
};

MODULE_DEVICE_TABLE(of, an30259a_match_table);

static const struct i2c_device_id an30259a_id[] = {
	{ "an30259a", 0 },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(i2c, an30259a_id);

static struct i2c_driver an30259a_driver = {
	.driver = {
		.name = "leds-an30259a",
		.of_match_table = of_match_ptr(an30259a_match_table),
	},
	.probe_new = an30259a_probe,
	.remove = an30259a_remove,
	.id_table = an30259a_id,
};

module_i2c_driver(an30259a_driver);

MODULE_AUTHOR("Simon Shields <simon@lineageos.org>");
MODULE_DESCRIPTION("AN30259A LED driver");
MODULE_LICENSE("GPL v2");