GNU Linux-libre 5.13.14-gnu1
[releases.git] / drivers / leds / leds-lp8501.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * TI LP8501 9 channel LED Driver
4  *
5  * Copyright (C) 2013 Texas Instruments
6  *
7  * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
8  */
9
10 #include <linux/delay.h>
11 #include <linux/firmware.h>
12 #include <linux/i2c.h>
13 #include <linux/init.h>
14 #include <linux/leds.h>
15 #include <linux/module.h>
16 #include <linux/mutex.h>
17 #include <linux/of.h>
18 #include <linux/platform_data/leds-lp55xx.h>
19 #include <linux/slab.h>
20
21 #include "leds-lp55xx-common.h"
22
23 #define LP8501_PROGRAM_LENGTH           32
24 #define LP8501_MAX_LEDS                 9
25
26 /* Registers */
27 #define LP8501_REG_ENABLE               0x00
28 #define LP8501_ENABLE                   BIT(6)
29 #define LP8501_EXEC_M                   0x3F
30 #define LP8501_EXEC_ENG1_M              0x30
31 #define LP8501_EXEC_ENG2_M              0x0C
32 #define LP8501_EXEC_ENG3_M              0x03
33 #define LP8501_RUN_ENG1                 0x20
34 #define LP8501_RUN_ENG2                 0x08
35 #define LP8501_RUN_ENG3                 0x02
36
37 #define LP8501_REG_OP_MODE              0x01
38 #define LP8501_MODE_ENG1_M              0x30
39 #define LP8501_MODE_ENG2_M              0x0C
40 #define LP8501_MODE_ENG3_M              0x03
41 #define LP8501_LOAD_ENG1                0x10
42 #define LP8501_LOAD_ENG2                0x04
43 #define LP8501_LOAD_ENG3                0x01
44
45 #define LP8501_REG_PWR_CONFIG           0x05
46 #define LP8501_PWR_CONFIG_M             0x03
47
48 #define LP8501_REG_LED_PWM_BASE         0x16
49
50 #define LP8501_REG_LED_CURRENT_BASE     0x26
51
52 #define LP8501_REG_CONFIG               0x36
53 #define LP8501_PWM_PSAVE                BIT(7)
54 #define LP8501_AUTO_INC                 BIT(6)
55 #define LP8501_PWR_SAVE                 BIT(5)
56 #define LP8501_CP_AUTO                  0x18
57 #define LP8501_INT_CLK                  BIT(0)
58 #define LP8501_DEFAULT_CFG      \
59         (LP8501_PWM_PSAVE | LP8501_AUTO_INC | LP8501_PWR_SAVE | LP8501_CP_AUTO)
60
61 #define LP8501_REG_RESET                0x3D
62 #define LP8501_RESET                    0xFF
63
64 #define LP8501_REG_PROG_PAGE_SEL        0x4F
65 #define LP8501_PAGE_ENG1                0
66 #define LP8501_PAGE_ENG2                1
67 #define LP8501_PAGE_ENG3                2
68
69 #define LP8501_REG_PROG_MEM             0x50
70
71 #define LP8501_ENG1_IS_LOADING(mode)    \
72         ((mode & LP8501_MODE_ENG1_M) == LP8501_LOAD_ENG1)
73 #define LP8501_ENG2_IS_LOADING(mode)    \
74         ((mode & LP8501_MODE_ENG2_M) == LP8501_LOAD_ENG2)
75 #define LP8501_ENG3_IS_LOADING(mode)    \
76         ((mode & LP8501_MODE_ENG3_M) == LP8501_LOAD_ENG3)
77
78 static inline void lp8501_wait_opmode_done(void)
79 {
80         usleep_range(1000, 2000);
81 }
82
83 static void lp8501_set_led_current(struct lp55xx_led *led, u8 led_current)
84 {
85         led->led_current = led_current;
86         lp55xx_write(led->chip, LP8501_REG_LED_CURRENT_BASE + led->chan_nr,
87                 led_current);
88 }
89
90 static int lp8501_post_init_device(struct lp55xx_chip *chip)
91 {
92         int ret;
93         u8 val = LP8501_DEFAULT_CFG;
94
95         ret = lp55xx_write(chip, LP8501_REG_ENABLE, LP8501_ENABLE);
96         if (ret)
97                 return ret;
98
99         /* Chip startup time is 500 us, 1 - 2 ms gives some margin */
100         usleep_range(1000, 2000);
101
102         if (chip->pdata->clock_mode != LP55XX_CLOCK_EXT)
103                 val |= LP8501_INT_CLK;
104
105         ret = lp55xx_write(chip, LP8501_REG_CONFIG, val);
106         if (ret)
107                 return ret;
108
109         /* Power selection for each output */
110         return lp55xx_update_bits(chip, LP8501_REG_PWR_CONFIG,
111                                 LP8501_PWR_CONFIG_M, chip->pdata->pwr_sel);
112 }
113
114 static void lp8501_load_engine(struct lp55xx_chip *chip)
115 {
116         enum lp55xx_engine_index idx = chip->engine_idx;
117         static const u8 mask[] = {
118                 [LP55XX_ENGINE_1] = LP8501_MODE_ENG1_M,
119                 [LP55XX_ENGINE_2] = LP8501_MODE_ENG2_M,
120                 [LP55XX_ENGINE_3] = LP8501_MODE_ENG3_M,
121         };
122
123         static const u8 val[] = {
124                 [LP55XX_ENGINE_1] = LP8501_LOAD_ENG1,
125                 [LP55XX_ENGINE_2] = LP8501_LOAD_ENG2,
126                 [LP55XX_ENGINE_3] = LP8501_LOAD_ENG3,
127         };
128
129         static const u8 page_sel[] = {
130                 [LP55XX_ENGINE_1] = LP8501_PAGE_ENG1,
131                 [LP55XX_ENGINE_2] = LP8501_PAGE_ENG2,
132                 [LP55XX_ENGINE_3] = LP8501_PAGE_ENG3,
133         };
134
135         lp55xx_update_bits(chip, LP8501_REG_OP_MODE, mask[idx], val[idx]);
136
137         lp8501_wait_opmode_done();
138
139         lp55xx_write(chip, LP8501_REG_PROG_PAGE_SEL, page_sel[idx]);
140 }
141
142 static void lp8501_stop_engine(struct lp55xx_chip *chip)
143 {
144         lp55xx_write(chip, LP8501_REG_OP_MODE, 0);
145         lp8501_wait_opmode_done();
146 }
147
148 static void lp8501_turn_off_channels(struct lp55xx_chip *chip)
149 {
150         int i;
151
152         for (i = 0; i < LP8501_MAX_LEDS; i++)
153                 lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + i, 0);
154 }
155
156 static void lp8501_run_engine(struct lp55xx_chip *chip, bool start)
157 {
158         int ret;
159         u8 mode;
160         u8 exec;
161
162         /* stop engine */
163         if (!start) {
164                 lp8501_stop_engine(chip);
165                 lp8501_turn_off_channels(chip);
166                 return;
167         }
168
169         /*
170          * To run the engine,
171          * operation mode and enable register should updated at the same time
172          */
173
174         ret = lp55xx_read(chip, LP8501_REG_OP_MODE, &mode);
175         if (ret)
176                 return;
177
178         ret = lp55xx_read(chip, LP8501_REG_ENABLE, &exec);
179         if (ret)
180                 return;
181
182         /* change operation mode to RUN only when each engine is loading */
183         if (LP8501_ENG1_IS_LOADING(mode)) {
184                 mode = (mode & ~LP8501_MODE_ENG1_M) | LP8501_RUN_ENG1;
185                 exec = (exec & ~LP8501_EXEC_ENG1_M) | LP8501_RUN_ENG1;
186         }
187
188         if (LP8501_ENG2_IS_LOADING(mode)) {
189                 mode = (mode & ~LP8501_MODE_ENG2_M) | LP8501_RUN_ENG2;
190                 exec = (exec & ~LP8501_EXEC_ENG2_M) | LP8501_RUN_ENG2;
191         }
192
193         if (LP8501_ENG3_IS_LOADING(mode)) {
194                 mode = (mode & ~LP8501_MODE_ENG3_M) | LP8501_RUN_ENG3;
195                 exec = (exec & ~LP8501_EXEC_ENG3_M) | LP8501_RUN_ENG3;
196         }
197
198         lp55xx_write(chip, LP8501_REG_OP_MODE, mode);
199         lp8501_wait_opmode_done();
200
201         lp55xx_update_bits(chip, LP8501_REG_ENABLE, LP8501_EXEC_M, exec);
202 }
203
204 static int lp8501_update_program_memory(struct lp55xx_chip *chip,
205                                         const u8 *data, size_t size)
206 {
207         u8 pattern[LP8501_PROGRAM_LENGTH] = {0};
208         unsigned cmd;
209         char c[3];
210         int update_size;
211         int nrchars;
212         int offset = 0;
213         int ret;
214         int i;
215
216         /* clear program memory before updating */
217         for (i = 0; i < LP8501_PROGRAM_LENGTH; i++)
218                 lp55xx_write(chip, LP8501_REG_PROG_MEM + i, 0);
219
220         i = 0;
221         while ((offset < size - 1) && (i < LP8501_PROGRAM_LENGTH)) {
222                 /* separate sscanfs because length is working only for %s */
223                 ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
224                 if (ret != 1)
225                         goto err;
226
227                 ret = sscanf(c, "%2x", &cmd);
228                 if (ret != 1)
229                         goto err;
230
231                 pattern[i] = (u8)cmd;
232                 offset += nrchars;
233                 i++;
234         }
235
236         /* Each instruction is 16bit long. Check that length is even */
237         if (i % 2)
238                 goto err;
239
240         update_size = i;
241         for (i = 0; i < update_size; i++)
242                 lp55xx_write(chip, LP8501_REG_PROG_MEM + i, pattern[i]);
243
244         return 0;
245
246 err:
247         dev_err(&chip->cl->dev, "wrong pattern format\n");
248         return -EINVAL;
249 }
250
251 static void lp8501_firmware_loaded(struct lp55xx_chip *chip)
252 {
253         const struct firmware *fw = chip->fw;
254
255         if (fw->size > LP8501_PROGRAM_LENGTH) {
256                 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
257                         fw->size);
258                 return;
259         }
260
261         /*
262          * Program memory sequence
263          *  1) set engine mode to "LOAD"
264          *  2) write firmware data into program memory
265          */
266
267         lp8501_load_engine(chip);
268         lp8501_update_program_memory(chip, fw->data, fw->size);
269 }
270
271 static int lp8501_led_brightness(struct lp55xx_led *led)
272 {
273         struct lp55xx_chip *chip = led->chip;
274         int ret;
275
276         mutex_lock(&chip->lock);
277         ret = lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + led->chan_nr,
278                      led->brightness);
279         mutex_unlock(&chip->lock);
280
281         return ret;
282 }
283
284 /* Chip specific configurations */
285 static struct lp55xx_device_config lp8501_cfg = {
286         .reset = {
287                 .addr = LP8501_REG_RESET,
288                 .val  = LP8501_RESET,
289         },
290         .enable = {
291                 .addr = LP8501_REG_ENABLE,
292                 .val  = LP8501_ENABLE,
293         },
294         .max_channel  = LP8501_MAX_LEDS,
295         .post_init_device   = lp8501_post_init_device,
296         .brightness_fn      = lp8501_led_brightness,
297         .set_led_current    = lp8501_set_led_current,
298         .firmware_cb        = lp8501_firmware_loaded,
299         .run_engine         = lp8501_run_engine,
300 };
301
302 static int lp8501_probe(struct i2c_client *client,
303                         const struct i2c_device_id *id)
304 {
305         int ret;
306         struct lp55xx_chip *chip;
307         struct lp55xx_led *led;
308         struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
309         struct device_node *np = dev_of_node(&client->dev);
310
311         chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
312         if (!chip)
313                 return -ENOMEM;
314
315         chip->cfg = &lp8501_cfg;
316
317         if (!pdata) {
318                 if (np) {
319                         pdata = lp55xx_of_populate_pdata(&client->dev, np,
320                                                          chip);
321                         if (IS_ERR(pdata))
322                                 return PTR_ERR(pdata);
323                 } else {
324                         dev_err(&client->dev, "no platform data\n");
325                         return -EINVAL;
326                 }
327         }
328
329         led = devm_kcalloc(&client->dev,
330                         pdata->num_channels, sizeof(*led), GFP_KERNEL);
331         if (!led)
332                 return -ENOMEM;
333
334         chip->cl = client;
335         chip->pdata = pdata;
336
337         mutex_init(&chip->lock);
338
339         i2c_set_clientdata(client, led);
340
341         ret = lp55xx_init_device(chip);
342         if (ret)
343                 goto err_init;
344
345         dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
346
347         ret = lp55xx_register_leds(led, chip);
348         if (ret)
349                 goto err_out;
350
351         ret = lp55xx_register_sysfs(chip);
352         if (ret) {
353                 dev_err(&client->dev, "registering sysfs failed\n");
354                 goto err_out;
355         }
356
357         return 0;
358
359 err_out:
360         lp55xx_deinit_device(chip);
361 err_init:
362         return ret;
363 }
364
365 static int lp8501_remove(struct i2c_client *client)
366 {
367         struct lp55xx_led *led = i2c_get_clientdata(client);
368         struct lp55xx_chip *chip = led->chip;
369
370         lp8501_stop_engine(chip);
371         lp55xx_unregister_sysfs(chip);
372         lp55xx_deinit_device(chip);
373
374         return 0;
375 }
376
377 static const struct i2c_device_id lp8501_id[] = {
378         { "lp8501",  0 },
379         { }
380 };
381 MODULE_DEVICE_TABLE(i2c, lp8501_id);
382
383 #ifdef CONFIG_OF
384 static const struct of_device_id of_lp8501_leds_match[] = {
385         { .compatible = "ti,lp8501", },
386         {},
387 };
388
389 MODULE_DEVICE_TABLE(of, of_lp8501_leds_match);
390 #endif
391
392 static struct i2c_driver lp8501_driver = {
393         .driver = {
394                 .name   = "lp8501",
395                 .of_match_table = of_match_ptr(of_lp8501_leds_match),
396         },
397         .probe          = lp8501_probe,
398         .remove         = lp8501_remove,
399         .id_table       = lp8501_id,
400 };
401
402 module_i2c_driver(lp8501_driver);
403
404 MODULE_DESCRIPTION("Texas Instruments LP8501 LED driver");
405 MODULE_AUTHOR("Milo Kim");
406 MODULE_LICENSE("GPL");