aboutsummaryrefslogtreecommitdiff
path: root/drivers/leds/leds-lm3697.c
blob: b71711aff8a3cb3fa8e9983ff34e1a19fdcc86ab (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
// SPDX-License-Identifier: GPL-2.0
// TI LM3697 LED chip family driver
// Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/

#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/regulator/consumer.h>
#include <linux/leds-ti-lmu-common.h>

#define LM3697_REV			0x0
#define LM3697_RESET			0x1
#define LM3697_OUTPUT_CONFIG		0x10
#define LM3697_CTRL_A_RAMP		0x11
#define LM3697_CTRL_B_RAMP		0x12
#define LM3697_CTRL_A_B_RT_RAMP		0x13
#define LM3697_CTRL_A_B_RAMP_CFG	0x14
#define LM3697_CTRL_A_B_BRT_CFG		0x16
#define LM3697_CTRL_A_FS_CURR_CFG	0x17
#define LM3697_CTRL_B_FS_CURR_CFG	0x18
#define LM3697_PWM_CFG			0x1c
#define LM3697_CTRL_A_BRT_LSB		0x20
#define LM3697_CTRL_A_BRT_MSB		0x21
#define LM3697_CTRL_B_BRT_LSB		0x22
#define LM3697_CTRL_B_BRT_MSB		0x23
#define LM3697_CTRL_ENABLE		0x24

#define LM3697_SW_RESET		BIT(0)

#define LM3697_CTRL_A_EN	BIT(0)
#define LM3697_CTRL_B_EN	BIT(1)
#define LM3697_CTRL_A_B_EN	(LM3697_CTRL_A_EN | LM3697_CTRL_B_EN)

#define LM3697_MAX_LED_STRINGS	3

#define LM3697_CONTROL_A	0
#define LM3697_CONTROL_B	1
#define LM3697_MAX_CONTROL_BANKS 2

/**
 * struct lm3697_led -
 * @hvled_strings: Array of LED strings associated with a control bank
 * @label: LED label
 * @led_dev: LED class device
 * @priv: Pointer to the device struct
 * @lmu_data: Register and setting values for common code
 * @control_bank: Control bank the LED is associated to. 0 is control bank A
 *		   1 is control bank B
 */
struct lm3697_led {
	u32 hvled_strings[LM3697_MAX_LED_STRINGS];
	char label[LED_MAX_NAME_SIZE];
	struct led_classdev led_dev;
	struct lm3697 *priv;
	struct ti_lmu_bank lmu_data;
	int control_bank;
	int enabled;
	int num_leds;
};

/**
 * struct lm3697 -
 * @enable_gpio: Hardware enable gpio
 * @regulator: LED supply regulator pointer
 * @client: Pointer to the I2C client
 * @regmap: Devices register map
 * @dev: Pointer to the devices device struct
 * @lock: Lock for reading/writing the device
 * @leds: Array of LED strings
 */
struct lm3697 {
	struct gpio_desc *enable_gpio;
	struct regulator *regulator;
	struct i2c_client *client;
	struct regmap *regmap;
	struct device *dev;
	struct mutex lock;

	int bank_cfg;

	struct lm3697_led leds[];
};

static const struct reg_default lm3697_reg_defs[] = {
	{LM3697_OUTPUT_CONFIG, 0x6},
	{LM3697_CTRL_A_RAMP, 0x0},
	{LM3697_CTRL_B_RAMP, 0x0},
	{LM3697_CTRL_A_B_RT_RAMP, 0x0},
	{LM3697_CTRL_A_B_RAMP_CFG, 0x0},
	{LM3697_CTRL_A_B_BRT_CFG, 0x0},
	{LM3697_CTRL_A_FS_CURR_CFG, 0x13},
	{LM3697_CTRL_B_FS_CURR_CFG, 0x13},
	{LM3697_PWM_CFG, 0xc},
	{LM3697_CTRL_A_BRT_LSB, 0x0},
	{LM3697_CTRL_A_BRT_MSB, 0x0},
	{LM3697_CTRL_B_BRT_LSB, 0x0},
	{LM3697_CTRL_B_BRT_MSB, 0x0},
	{LM3697_CTRL_ENABLE, 0x0},
};

static const struct regmap_config lm3697_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,

	.max_register = LM3697_CTRL_ENABLE,
	.reg_defaults = lm3697_reg_defs,
	.num_reg_defaults = ARRAY_SIZE(lm3697_reg_defs),
	.cache_type = REGCACHE_FLAT,
};

static int lm3697_brightness_set(struct led_classdev *led_cdev,
				enum led_brightness brt_val)
{
	struct lm3697_led *led = container_of(led_cdev, struct lm3697_led,
					      led_dev);
	int ctrl_en_val = (1 << led->control_bank);
	int ret;

	mutex_lock(&led->priv->lock);

	if (brt_val == LED_OFF) {
		ret = regmap_update_bits(led->priv->regmap, LM3697_CTRL_ENABLE,
					 ctrl_en_val, ~ctrl_en_val);
		if (ret) {
			dev_err(&led->priv->client->dev, "Cannot write ctrl register\n");
			goto brightness_out;
		}

		led->enabled = LED_OFF;
	} else {
		ret = ti_lmu_common_set_brightness(&led->lmu_data, brt_val);
		if (ret) {
			dev_err(&led->priv->client->dev,
				"Cannot write brightness\n");
			goto brightness_out;
		}

		if (!led->enabled) {
			ret = regmap_update_bits(led->priv->regmap,
						 LM3697_CTRL_ENABLE,
						 ctrl_en_val, ctrl_en_val);
			if (ret) {
				dev_err(&led->priv->client->dev,
					"Cannot enable the device\n");
				goto brightness_out;
			}

			led->enabled = brt_val;
		}
	}

brightness_out:
	mutex_unlock(&led->priv->lock);
	return ret;
}

static int lm3697_init(struct lm3697 *priv)
{
	struct lm3697_led *led;
	int i, ret;

	if (priv->enable_gpio) {
		gpiod_direction_output(priv->enable_gpio, 1);
	} else {
		ret = regmap_write(priv->regmap, LM3697_RESET, LM3697_SW_RESET);
		if (ret) {
			dev_err(&priv->client->dev, "Cannot reset the device\n");
			goto out;
		}
	}

	ret = regmap_write(priv->regmap, LM3697_CTRL_ENABLE, 0x0);
	if (ret) {
		dev_err(&priv->client->dev, "Cannot write ctrl enable\n");
		goto out;
	}

	ret = regmap_write(priv->regmap, LM3697_OUTPUT_CONFIG, priv->bank_cfg);
	if (ret)
		dev_err(&priv->client->dev, "Cannot write OUTPUT config\n");

	for (i = 0; i < LM3697_MAX_CONTROL_BANKS; i++) {
		led = &priv->leds[i];
		ret = ti_lmu_common_set_ramp(&led->lmu_data);
		if (ret)
			dev_err(&priv->client->dev, "Setting the ramp rate failed\n");
	}
out:
	return ret;
}

static int lm3697_probe_dt(struct lm3697 *priv)
{
	struct fwnode_handle *child = NULL;
	struct lm3697_led *led;
	const char *name;
	int control_bank;
	size_t i = 0;
	int ret = -EINVAL;
	int j;

	priv->enable_gpio = devm_gpiod_get_optional(&priv->client->dev,
						   "enable", GPIOD_OUT_LOW);
	if (IS_ERR(priv->enable_gpio)) {
		ret = PTR_ERR(priv->enable_gpio);
		dev_err(&priv->client->dev, "Failed to get enable gpio: %d\n",
			ret);
		return ret;
	}

	priv->regulator = devm_regulator_get(&priv->client->dev, "vled");
	if (IS_ERR(priv->regulator))
		priv->regulator = NULL;

	device_for_each_child_node(priv->dev, child) {
		ret = fwnode_property_read_u32(child, "reg", &control_bank);
		if (ret) {
			dev_err(&priv->client->dev, "reg property missing\n");
			fwnode_handle_put(child);
			goto child_out;
		}

		if (control_bank > LM3697_CONTROL_B) {
			dev_err(&priv->client->dev, "reg property is invalid\n");
			ret = -EINVAL;
			fwnode_handle_put(child);
			goto child_out;
		}

		led = &priv->leds[i];

		ret = ti_lmu_common_get_brt_res(&priv->client->dev,
						child, &led->lmu_data);
		if (ret)
			dev_warn(&priv->client->dev, "brightness resolution property missing\n");

		led->control_bank = control_bank;
		led->lmu_data.regmap = priv->regmap;
		led->lmu_data.runtime_ramp_reg = LM3697_CTRL_A_RAMP +
						 control_bank;
		led->lmu_data.msb_brightness_reg = LM3697_CTRL_A_BRT_MSB +
						   led->control_bank * 2;
		led->lmu_data.lsb_brightness_reg = LM3697_CTRL_A_BRT_LSB +
						   led->control_bank * 2;

		led->num_leds = fwnode_property_count_u32(child, "led-sources");
		if (led->num_leds > LM3697_MAX_LED_STRINGS) {
			dev_err(&priv->client->dev, "To many LED strings defined\n");
			continue;
		}

		ret = fwnode_property_read_u32_array(child, "led-sources",
						    led->hvled_strings,
						    led->num_leds);
		if (ret) {
			dev_err(&priv->client->dev, "led-sources property missing\n");
			fwnode_handle_put(child);
			goto child_out;
		}

		for (j = 0; j < led->num_leds; j++)
			priv->bank_cfg |=
				(led->control_bank << led->hvled_strings[j]);

		ret = ti_lmu_common_get_ramp_params(&priv->client->dev,
						    child, &led->lmu_data);
		if (ret)
			dev_warn(&priv->client->dev, "runtime-ramp properties missing\n");

		fwnode_property_read_string(child, "linux,default-trigger",
					    &led->led_dev.default_trigger);

		ret = fwnode_property_read_string(child, "label", &name);
		if (ret)
			snprintf(led->label, sizeof(led->label),
				"%s::", priv->client->name);
		else
			snprintf(led->label, sizeof(led->label),
				 "%s:%s", priv->client->name, name);

		led->priv = priv;
		led->led_dev.name = led->label;
		led->led_dev.max_brightness = led->lmu_data.max_brightness;
		led->led_dev.brightness_set_blocking = lm3697_brightness_set;

		ret = devm_led_classdev_register(priv->dev, &led->led_dev);
		if (ret) {
			dev_err(&priv->client->dev, "led register err: %d\n",
				ret);
			fwnode_handle_put(child);
			goto child_out;
		}

		i++;
	}

child_out:
	return ret;
}

static int lm3697_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct lm3697 *led;
	int count;
	int ret;

	count = device_get_child_node_count(&client->dev);
	if (!count) {
		dev_err(&client->dev, "LEDs are not defined in device tree!");
		return -ENODEV;
	}

	led = devm_kzalloc(&client->dev, struct_size(led, leds, count),
			   GFP_KERNEL);
	if (!led)
		return -ENOMEM;

	mutex_init(&led->lock);
	i2c_set_clientdata(client, led);

	led->client = client;
	led->dev = &client->dev;
	led->regmap = devm_regmap_init_i2c(client, &lm3697_regmap_config);
	if (IS_ERR(led->regmap)) {
		ret = PTR_ERR(led->regmap);
		dev_err(&client->dev, "Failed to allocate register map: %d\n",
			ret);
		return ret;
	}

	ret = lm3697_probe_dt(led);
	if (ret)
		return ret;

	return lm3697_init(led);
}

static int lm3697_remove(struct i2c_client *client)
{
	struct lm3697 *led = i2c_get_clientdata(client);
	int ret;

	ret = regmap_update_bits(led->regmap, LM3697_CTRL_ENABLE,
				 LM3697_CTRL_A_B_EN, 0);
	if (ret) {
		dev_err(&led->client->dev, "Failed to disable the device\n");
		return ret;
	}

	if (led->enable_gpio)
		gpiod_direction_output(led->enable_gpio, 0);

	if (led->regulator) {
		ret = regulator_disable(led->regulator);
		if (ret)
			dev_err(&led->client->dev,
				"Failed to disable regulator\n");
	}

	mutex_destroy(&led->lock);

	return 0;
}

static const struct i2c_device_id lm3697_id[] = {
	{ "lm3697", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, lm3697_id);

static const struct of_device_id of_lm3697_leds_match[] = {
	{ .compatible = "ti,lm3697", },
	{},
};
MODULE_DEVICE_TABLE(of, of_lm3697_leds_match);

static struct i2c_driver lm3697_driver = {
	.driver = {
		.name	= "lm3697",
		.of_match_table = of_lm3697_leds_match,
	},
	.probe		= lm3697_probe,
	.remove		= lm3697_remove,
	.id_table	= lm3697_id,
};
module_i2c_driver(lm3697_driver);

MODULE_DESCRIPTION("Texas Instruments LM3697 LED driver");
MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
MODULE_LICENSE("GPL v2");