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16#include <linux/gpio/consumer.h>
17#include <linux/i2c.h>
18#include <linux/init.h>
19#include <linux/leds.h>
20#include <linux/module.h>
21#include <linux/mutex.h>
22#include <linux/of.h>
23#include <linux/of_gpio.h>
24#include <linux/regmap.h>
25#include <linux/regulator/consumer.h>
26#include <linux/slab.h>
27#include <uapi/linux/uleds.h>
28
29#define LM3692X_REV 0x0
30#define LM3692X_RESET 0x1
31#define LM3692X_EN 0x10
32#define LM3692X_BRT_CTRL 0x11
33#define LM3692X_PWM_CTRL 0x12
34#define LM3692X_BOOST_CTRL 0x13
35#define LM3692X_AUTO_FREQ_HI 0x15
36#define LM3692X_AUTO_FREQ_LO 0x16
37#define LM3692X_BL_ADJ_THRESH 0x17
38#define LM3692X_BRT_LSB 0x18
39#define LM3692X_BRT_MSB 0x19
40#define LM3692X_FAULT_CTRL 0x1e
41#define LM3692X_FAULT_FLAGS 0x1f
42
43#define LM3692X_SW_RESET BIT(0)
44#define LM3692X_DEVICE_EN BIT(0)
45#define LM3692X_LED1_EN BIT(1)
46#define LM3692X_LED2_EN BIT(2)
47
48
49#define LM3692X_BL_ADJ_POL BIT(0)
50#define LM3692X_RAMP_RATE_125us 0x00
51#define LM3692X_RAMP_RATE_250us BIT(1)
52#define LM3692X_RAMP_RATE_500us BIT(2)
53#define LM3692X_RAMP_RATE_1ms (BIT(1) | BIT(2))
54#define LM3692X_RAMP_RATE_2ms BIT(3)
55#define LM3692X_RAMP_RATE_4ms (BIT(3) | BIT(1))
56#define LM3692X_RAMP_RATE_8ms (BIT(2) | BIT(3))
57#define LM3692X_RAMP_RATE_16ms (BIT(1) | BIT(2) | BIT(3))
58#define LM3692X_RAMP_EN BIT(4)
59#define LM3692X_BRHT_MODE_REG 0x00
60#define LM3692X_BRHT_MODE_PWM BIT(5)
61#define LM3692X_BRHT_MODE_MULTI_RAMP BIT(6)
62#define LM3692X_BRHT_MODE_RAMP_MULTI (BIT(5) | BIT(6))
63#define LM3692X_MAP_MODE_EXP BIT(7)
64
65
66#define LM3692X_PWM_FILTER_100 BIT(0)
67#define LM3692X_PWM_FILTER_150 BIT(1)
68#define LM3692X_PWM_FILTER_200 (BIT(0) | BIT(1))
69#define LM3692X_PWM_HYSTER_1LSB BIT(2)
70#define LM3692X_PWM_HYSTER_2LSB BIT(3)
71#define LM3692X_PWM_HYSTER_3LSB (BIT(3) | BIT(2))
72#define LM3692X_PWM_HYSTER_4LSB BIT(4)
73#define LM3692X_PWM_HYSTER_5LSB (BIT(4) | BIT(2))
74#define LM3692X_PWM_HYSTER_6LSB (BIT(4) | BIT(3))
75#define LM3692X_PWM_POLARITY BIT(5)
76#define LM3692X_PWM_SAMP_4MHZ BIT(6)
77#define LM3692X_PWM_SAMP_24MHZ BIT(7)
78
79
80#define LM3692X_OCP_PROT_1A BIT(0)
81#define LM3692X_OCP_PROT_1_25A BIT(1)
82#define LM3692X_OCP_PROT_1_5A (BIT(0) | BIT(1))
83#define LM3692X_OVP_21V BIT(2)
84#define LM3692X_OVP_25V BIT(3)
85#define LM3692X_OVP_29V (BIT(2) | BIT(3))
86#define LM3692X_MIN_IND_22UH BIT(4)
87#define LM3692X_BOOST_SW_1MHZ BIT(5)
88#define LM3692X_BOOST_SW_NO_SHIFT BIT(6)
89
90
91#define LM3692X_FAULT_CTRL_OVP BIT(0)
92#define LM3692X_FAULT_CTRL_OCP BIT(1)
93#define LM3692X_FAULT_CTRL_TSD BIT(2)
94#define LM3692X_FAULT_CTRL_OPEN BIT(3)
95
96
97#define LM3692X_FAULT_FLAG_OVP BIT(0)
98#define LM3692X_FAULT_FLAG_OCP BIT(1)
99#define LM3692X_FAULT_FLAG_TSD BIT(2)
100#define LM3692X_FAULT_FLAG_SHRT BIT(3)
101#define LM3692X_FAULT_FLAG_OPEN BIT(4)
102
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112
113struct lm3692x_led {
114 struct mutex lock;
115 struct i2c_client *client;
116 struct led_classdev led_dev;
117 struct regmap *regmap;
118 struct gpio_desc *enable_gpio;
119 struct regulator *regulator;
120 char label[LED_MAX_NAME_SIZE];
121};
122
123static const struct reg_default lm3692x_reg_defs[] = {
124 {LM3692X_EN, 0xf},
125 {LM3692X_BRT_CTRL, 0x61},
126 {LM3692X_PWM_CTRL, 0x73},
127 {LM3692X_BOOST_CTRL, 0x6f},
128 {LM3692X_AUTO_FREQ_HI, 0x0},
129 {LM3692X_AUTO_FREQ_LO, 0x0},
130 {LM3692X_BL_ADJ_THRESH, 0x0},
131 {LM3692X_BRT_LSB, 0x7},
132 {LM3692X_BRT_MSB, 0xff},
133 {LM3692X_FAULT_CTRL, 0x7},
134};
135
136static const struct regmap_config lm3692x_regmap_config = {
137 .reg_bits = 8,
138 .val_bits = 8,
139
140 .max_register = LM3692X_FAULT_FLAGS,
141 .reg_defaults = lm3692x_reg_defs,
142 .num_reg_defaults = ARRAY_SIZE(lm3692x_reg_defs),
143 .cache_type = REGCACHE_RBTREE,
144};
145
146static int lm3692x_fault_check(struct lm3692x_led *led)
147{
148 int ret;
149 unsigned int read_buf;
150
151 ret = regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
152 if (ret)
153 return ret;
154
155 if (read_buf)
156 dev_err(&led->client->dev, "Detected a fault 0x%X\n", read_buf);
157
158
159
160
161 regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);
162 if (read_buf)
163 dev_err(&led->client->dev, "Second read of fault flags 0x%X\n",
164 read_buf);
165
166 return read_buf;
167}
168
169static int lm3692x_brightness_set(struct led_classdev *led_cdev,
170 enum led_brightness brt_val)
171{
172 struct lm3692x_led *led =
173 container_of(led_cdev, struct lm3692x_led, led_dev);
174 int ret;
175 int led_brightness_lsb = (brt_val >> 5);
176
177 mutex_lock(&led->lock);
178
179 ret = lm3692x_fault_check(led);
180 if (ret) {
181 dev_err(&led->client->dev, "Cannot read/clear faults\n");
182 goto out;
183 }
184
185 ret = regmap_write(led->regmap, LM3692X_BRT_MSB, brt_val);
186 if (ret) {
187 dev_err(&led->client->dev, "Cannot write MSB\n");
188 goto out;
189 }
190
191 ret = regmap_write(led->regmap, LM3692X_BRT_LSB, led_brightness_lsb);
192 if (ret) {
193 dev_err(&led->client->dev, "Cannot write LSB\n");
194 goto out;
195 }
196out:
197 mutex_unlock(&led->lock);
198 return ret;
199}
200
201static int lm3692x_init(struct lm3692x_led *led)
202{
203 int ret;
204
205 if (led->regulator) {
206 ret = regulator_enable(led->regulator);
207 if (ret) {
208 dev_err(&led->client->dev,
209 "Failed to enable regulator\n");
210 return ret;
211 }
212 }
213
214 if (led->enable_gpio)
215 gpiod_direction_output(led->enable_gpio, 1);
216
217 ret = lm3692x_fault_check(led);
218 if (ret) {
219 dev_err(&led->client->dev, "Cannot read/clear faults\n");
220 goto out;
221 }
222
223 ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, 0x00);
224 if (ret)
225 goto out;
226
227
228
229
230
231
232 ret = regmap_write(led->regmap, LM3692X_PWM_CTRL,
233 LM3692X_PWM_FILTER_100 | LM3692X_PWM_SAMP_24MHZ);
234 if (ret)
235 goto out;
236
237 ret = regmap_write(led->regmap, LM3692X_BOOST_CTRL,
238 LM3692X_BRHT_MODE_RAMP_MULTI |
239 LM3692X_BL_ADJ_POL |
240 LM3692X_RAMP_RATE_250us);
241 if (ret)
242 goto out;
243
244 ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_HI, 0x00);
245 if (ret)
246 goto out;
247
248 ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_LO, 0x00);
249 if (ret)
250 goto out;
251
252 ret = regmap_write(led->regmap, LM3692X_BL_ADJ_THRESH, 0x00);
253 if (ret)
254 goto out;
255
256 ret = regmap_write(led->regmap, LM3692X_BRT_CTRL,
257 LM3692X_BL_ADJ_POL | LM3692X_PWM_HYSTER_4LSB);
258 if (ret)
259 goto out;
260
261 return ret;
262out:
263 dev_err(&led->client->dev, "Fail writing initialization values\n");
264
265 if (led->enable_gpio)
266 gpiod_direction_output(led->enable_gpio, 0);
267
268 if (led->regulator) {
269 ret = regulator_disable(led->regulator);
270 if (ret)
271 dev_err(&led->client->dev,
272 "Failed to disable regulator\n");
273 }
274
275 return ret;
276}
277
278static int lm3692x_probe(struct i2c_client *client,
279 const struct i2c_device_id *id)
280{
281 int ret;
282 struct lm3692x_led *led;
283 struct device_node *np = client->dev.of_node;
284 struct device_node *child_node;
285 const char *name;
286
287 led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
288 if (!led)
289 return -ENOMEM;
290
291 for_each_available_child_of_node(np, child_node) {
292 led->led_dev.default_trigger = of_get_property(child_node,
293 "linux,default-trigger",
294 NULL);
295
296 ret = of_property_read_string(child_node, "label", &name);
297 if (!ret)
298 snprintf(led->label, sizeof(led->label),
299 "%s:%s", id->name, name);
300 else
301 snprintf(led->label, sizeof(led->label),
302 "%s::backlight_cluster", id->name);
303 };
304
305 led->enable_gpio = devm_gpiod_get_optional(&client->dev,
306 "enable", GPIOD_OUT_LOW);
307 if (IS_ERR(led->enable_gpio)) {
308 ret = PTR_ERR(led->enable_gpio);
309 dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
310 return ret;
311 }
312
313 led->regulator = devm_regulator_get(&client->dev, "vled");
314 if (IS_ERR(led->regulator))
315 led->regulator = NULL;
316
317 led->client = client;
318 led->led_dev.name = led->label;
319 led->led_dev.brightness_set_blocking = lm3692x_brightness_set;
320
321 mutex_init(&led->lock);
322
323 i2c_set_clientdata(client, led);
324
325 led->regmap = devm_regmap_init_i2c(client, &lm3692x_regmap_config);
326 if (IS_ERR(led->regmap)) {
327 ret = PTR_ERR(led->regmap);
328 dev_err(&client->dev, "Failed to allocate register map: %d\n",
329 ret);
330 return ret;
331 }
332
333 ret = lm3692x_init(led);
334 if (ret)
335 return ret;
336
337 ret = devm_led_classdev_register(&client->dev, &led->led_dev);
338 if (ret) {
339 dev_err(&client->dev, "led register err: %d\n", ret);
340 return ret;
341 }
342
343 return 0;
344}
345
346static int lm3692x_remove(struct i2c_client *client)
347{
348 struct lm3692x_led *led = i2c_get_clientdata(client);
349 int ret;
350
351 if (led->enable_gpio)
352 gpiod_direction_output(led->enable_gpio, 0);
353
354 if (led->regulator) {
355 ret = regulator_disable(led->regulator);
356 if (ret)
357 dev_err(&led->client->dev,
358 "Failed to disable regulator\n");
359 }
360
361 mutex_destroy(&led->lock);
362
363 return 0;
364}
365
366static const struct i2c_device_id lm3692x_id[] = {
367 { "lm36922", 0 },
368 { "lm36923", 1 },
369 { }
370};
371MODULE_DEVICE_TABLE(i2c, lm3692x_id);
372
373static const struct of_device_id of_lm3692x_leds_match[] = {
374 { .compatible = "ti,lm36922", },
375 { .compatible = "ti,lm36923", },
376 {},
377};
378MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match);
379
380static struct i2c_driver lm3692x_driver = {
381 .driver = {
382 .name = "lm3692x",
383 .of_match_table = of_lm3692x_leds_match,
384 },
385 .probe = lm3692x_probe,
386 .remove = lm3692x_remove,
387 .id_table = lm3692x_id,
388};
389module_i2c_driver(lm3692x_driver);
390
391MODULE_DESCRIPTION("Texas Instruments LM3692X LED driver");
392MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
393MODULE_LICENSE("GPL v2");
394
