1 // SPDX-License-Identifier: GPL-2.0
2 // TI LM3697 LED chip family driver
3 // Copyright (C) 2018 Texas Instruments Incorporated - https://www.ti.com/
5 #include <linux/gpio/consumer.h>
8 #include <linux/of_gpio.h>
9 #include <linux/regulator/consumer.h>
10 #include <linux/leds-ti-lmu-common.h>
12 #define LM3697_REV 0x0
13 #define LM3697_RESET 0x1
14 #define LM3697_OUTPUT_CONFIG 0x10
15 #define LM3697_CTRL_A_RAMP 0x11
16 #define LM3697_CTRL_B_RAMP 0x12
17 #define LM3697_CTRL_A_B_RT_RAMP 0x13
18 #define LM3697_CTRL_A_B_RAMP_CFG 0x14
19 #define LM3697_CTRL_A_B_BRT_CFG 0x16
20 #define LM3697_CTRL_A_FS_CURR_CFG 0x17
21 #define LM3697_CTRL_B_FS_CURR_CFG 0x18
22 #define LM3697_PWM_CFG 0x1c
23 #define LM3697_CTRL_A_BRT_LSB 0x20
24 #define LM3697_CTRL_A_BRT_MSB 0x21
25 #define LM3697_CTRL_B_BRT_LSB 0x22
26 #define LM3697_CTRL_B_BRT_MSB 0x23
27 #define LM3697_CTRL_ENABLE 0x24
29 #define LM3697_SW_RESET BIT(0)
31 #define LM3697_CTRL_A_EN BIT(0)
32 #define LM3697_CTRL_B_EN BIT(1)
33 #define LM3697_CTRL_A_B_EN (LM3697_CTRL_A_EN | LM3697_CTRL_B_EN)
35 #define LM3697_MAX_LED_STRINGS 3
37 #define LM3697_CONTROL_A 0
38 #define LM3697_CONTROL_B 1
39 #define LM3697_MAX_CONTROL_BANKS 2
43 * @hvled_strings: Array of LED strings associated with a control bank
45 * @led_dev: LED class device
46 * @priv: Pointer to the device struct
47 * @lmu_data: Register and setting values for common code
48 * @control_bank: Control bank the LED is associated to. 0 is control bank A
50 * @enabled: LED brightness level (or LED_OFF)
51 * @num_leds: Number of LEDs available
54 u32 hvled_strings[LM3697_MAX_LED_STRINGS];
55 char label[LED_MAX_NAME_SIZE];
56 struct led_classdev led_dev;
58 struct ti_lmu_bank lmu_data;
66 * @enable_gpio: Hardware enable gpio
67 * @regulator: LED supply regulator pointer
68 * @client: Pointer to the I2C client
69 * @regmap: Devices register map
70 * @dev: Pointer to the devices device struct
71 * @lock: Lock for reading/writing the device
72 * @leds: Array of LED strings
73 * @bank_cfg: OUTPUT_CONFIG register values
74 * @num_banks: Number of control banks
77 struct gpio_desc *enable_gpio;
78 struct regulator *regulator;
79 struct i2c_client *client;
80 struct regmap *regmap;
87 struct lm3697_led leds[];
90 static const struct reg_default lm3697_reg_defs[] = {
91 {LM3697_OUTPUT_CONFIG, 0x6},
92 {LM3697_CTRL_A_RAMP, 0x0},
93 {LM3697_CTRL_B_RAMP, 0x0},
94 {LM3697_CTRL_A_B_RT_RAMP, 0x0},
95 {LM3697_CTRL_A_B_RAMP_CFG, 0x0},
96 {LM3697_CTRL_A_B_BRT_CFG, 0x0},
97 {LM3697_CTRL_A_FS_CURR_CFG, 0x13},
98 {LM3697_CTRL_B_FS_CURR_CFG, 0x13},
99 {LM3697_PWM_CFG, 0xc},
100 {LM3697_CTRL_A_BRT_LSB, 0x0},
101 {LM3697_CTRL_A_BRT_MSB, 0x0},
102 {LM3697_CTRL_B_BRT_LSB, 0x0},
103 {LM3697_CTRL_B_BRT_MSB, 0x0},
104 {LM3697_CTRL_ENABLE, 0x0},
107 static const struct regmap_config lm3697_regmap_config = {
111 .max_register = LM3697_CTRL_ENABLE,
112 .reg_defaults = lm3697_reg_defs,
113 .num_reg_defaults = ARRAY_SIZE(lm3697_reg_defs),
114 .cache_type = REGCACHE_FLAT,
117 static int lm3697_brightness_set(struct led_classdev *led_cdev,
118 enum led_brightness brt_val)
120 struct lm3697_led *led = container_of(led_cdev, struct lm3697_led,
122 int ctrl_en_val = (1 << led->control_bank);
123 struct device *dev = led->priv->dev;
126 mutex_lock(&led->priv->lock);
128 if (brt_val == LED_OFF) {
129 ret = regmap_update_bits(led->priv->regmap, LM3697_CTRL_ENABLE,
130 ctrl_en_val, ~ctrl_en_val);
132 dev_err(dev, "Cannot write ctrl register\n");
136 led->enabled = LED_OFF;
138 ret = ti_lmu_common_set_brightness(&led->lmu_data, brt_val);
140 dev_err(dev, "Cannot write brightness\n");
145 ret = regmap_update_bits(led->priv->regmap,
147 ctrl_en_val, ctrl_en_val);
149 dev_err(dev, "Cannot enable the device\n");
153 led->enabled = brt_val;
158 mutex_unlock(&led->priv->lock);
162 static int lm3697_init(struct lm3697 *priv)
164 struct device *dev = priv->dev;
165 struct lm3697_led *led;
168 if (priv->enable_gpio) {
169 gpiod_direction_output(priv->enable_gpio, 1);
171 ret = regmap_write(priv->regmap, LM3697_RESET, LM3697_SW_RESET);
173 dev_err(dev, "Cannot reset the device\n");
178 ret = regmap_write(priv->regmap, LM3697_CTRL_ENABLE, 0x0);
180 dev_err(dev, "Cannot write ctrl enable\n");
184 ret = regmap_write(priv->regmap, LM3697_OUTPUT_CONFIG, priv->bank_cfg);
186 dev_err(dev, "Cannot write OUTPUT config\n");
188 for (i = 0; i < priv->num_banks; i++) {
189 led = &priv->leds[i];
190 ret = ti_lmu_common_set_ramp(&led->lmu_data);
192 dev_err(dev, "Setting the ramp rate failed\n");
198 static int lm3697_probe_dt(struct lm3697 *priv)
200 struct fwnode_handle *child = NULL;
201 struct device *dev = priv->dev;
202 struct lm3697_led *led;
208 priv->enable_gpio = devm_gpiod_get_optional(dev, "enable",
210 if (IS_ERR(priv->enable_gpio))
211 return dev_err_probe(dev, PTR_ERR(priv->enable_gpio),
212 "Failed to get enable GPIO\n");
214 priv->regulator = devm_regulator_get(dev, "vled");
215 if (IS_ERR(priv->regulator))
216 priv->regulator = NULL;
218 device_for_each_child_node(dev, child) {
219 struct led_init_data init_data = {};
221 ret = fwnode_property_read_u32(child, "reg", &control_bank);
223 dev_err(dev, "reg property missing\n");
224 fwnode_handle_put(child);
228 if (control_bank > LM3697_CONTROL_B) {
229 dev_err(dev, "reg property is invalid\n");
231 fwnode_handle_put(child);
235 led = &priv->leds[i];
237 ret = ti_lmu_common_get_brt_res(dev, child, &led->lmu_data);
240 "brightness resolution property missing\n");
242 led->control_bank = control_bank;
243 led->lmu_data.regmap = priv->regmap;
244 led->lmu_data.runtime_ramp_reg = LM3697_CTRL_A_RAMP +
246 led->lmu_data.msb_brightness_reg = LM3697_CTRL_A_BRT_MSB +
247 led->control_bank * 2;
248 led->lmu_data.lsb_brightness_reg = LM3697_CTRL_A_BRT_LSB +
249 led->control_bank * 2;
251 led->num_leds = fwnode_property_count_u32(child, "led-sources");
252 if (led->num_leds > LM3697_MAX_LED_STRINGS) {
253 dev_err(dev, "Too many LED strings defined\n");
257 ret = fwnode_property_read_u32_array(child, "led-sources",
261 dev_err(dev, "led-sources property missing\n");
262 fwnode_handle_put(child);
266 for (j = 0; j < led->num_leds; j++)
268 (led->control_bank << led->hvled_strings[j]);
270 ret = ti_lmu_common_get_ramp_params(dev, child, &led->lmu_data);
272 dev_warn(dev, "runtime-ramp properties missing\n");
274 init_data.fwnode = child;
275 init_data.devicename = priv->client->name;
276 /* for backwards compatibility if `label` is not present */
277 init_data.default_label = ":";
280 led->led_dev.max_brightness = led->lmu_data.max_brightness;
281 led->led_dev.brightness_set_blocking = lm3697_brightness_set;
283 ret = devm_led_classdev_register_ext(dev, &led->led_dev,
286 dev_err(dev, "led register err: %d\n", ret);
287 fwnode_handle_put(child);
298 static int lm3697_probe(struct i2c_client *client,
299 const struct i2c_device_id *id)
301 struct device *dev = &client->dev;
306 count = device_get_child_node_count(dev);
307 if (!count || count > LM3697_MAX_CONTROL_BANKS) {
308 dev_err(dev, "Strange device tree!");
312 led = devm_kzalloc(dev, struct_size(led, leds, count), GFP_KERNEL);
316 mutex_init(&led->lock);
317 i2c_set_clientdata(client, led);
319 led->client = client;
321 led->num_banks = count;
322 led->regmap = devm_regmap_init_i2c(client, &lm3697_regmap_config);
323 if (IS_ERR(led->regmap)) {
324 ret = PTR_ERR(led->regmap);
325 dev_err(dev, "Failed to allocate register map: %d\n", ret);
329 ret = lm3697_probe_dt(led);
333 return lm3697_init(led);
336 static int lm3697_remove(struct i2c_client *client)
338 struct lm3697 *led = i2c_get_clientdata(client);
339 struct device *dev = &led->client->dev;
342 ret = regmap_update_bits(led->regmap, LM3697_CTRL_ENABLE,
343 LM3697_CTRL_A_B_EN, 0);
345 dev_err(dev, "Failed to disable the device\n");
349 if (led->enable_gpio)
350 gpiod_direction_output(led->enable_gpio, 0);
352 if (led->regulator) {
353 ret = regulator_disable(led->regulator);
355 dev_err(dev, "Failed to disable regulator\n");
358 mutex_destroy(&led->lock);
363 static const struct i2c_device_id lm3697_id[] = {
367 MODULE_DEVICE_TABLE(i2c, lm3697_id);
369 static const struct of_device_id of_lm3697_leds_match[] = {
370 { .compatible = "ti,lm3697", },
373 MODULE_DEVICE_TABLE(of, of_lm3697_leds_match);
375 static struct i2c_driver lm3697_driver = {
378 .of_match_table = of_lm3697_leds_match,
380 .probe = lm3697_probe,
381 .remove = lm3697_remove,
382 .id_table = lm3697_id,
384 module_i2c_driver(lm3697_driver);
386 MODULE_DESCRIPTION("Texas Instruments LM3697 LED driver");
387 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
388 MODULE_LICENSE("GPL v2");