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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm...
[linux-2.6.git] / drivers / leds / leds-pca963x.c
blob82589c0a5689ff7abd033bd73b11ab42198ea0b9
1 /*
2 * Copyright 2011 bct electronic GmbH
3 * Copyright 2013 Qtechnology/AS
4 *
5 * Author: Peter Meerwald <p.meerwald@bct-electronic.com>
6 * Author: Ricardo Ribalda <ricardo.ribalda@gmail.com>
7 *
8 * Based on leds-pca955x.c
9 *
10 * This file is subject to the terms and conditions of version 2 of
11 * the GNU General Public License. See the file COPYING in the main
12 * directory of this archive for more details.
13 *
14 * LED driver for the PCA9633 I2C LED driver (7-bit slave address 0x62)
15 * LED driver for the PCA9634 I2C LED driver (7-bit slave address set by hw.)
16 *
17 * Note that hardware blinking violates the leds infrastructure driver
18 * interface since the hardware only supports blinking all LEDs with the
19 * same delay_on/delay_off rates. That is, only the LEDs that are set to
20 * blink will actually blink but all LEDs that are set to blink will blink
21 * in identical fashion. The delay_on/delay_off values of the last LED
22 * that is set to blink will be used for all of the blinking LEDs.
23 * Hardware blinking is disabled by default but can be enabled by setting
24 * the 'blink_type' member in the platform_data struct to 'PCA963X_HW_BLINK'
25 * or by adding the 'nxp,hw-blink' property to the DTS.
26 */
27
28 #include <linux/module.h>
29 #include <linux/delay.h>
30 #include <linux/string.h>
31 #include <linux/ctype.h>
32 #include <linux/leds.h>
33 #include <linux/err.h>
34 #include <linux/i2c.h>
35 #include <linux/workqueue.h>
36 #include <linux/slab.h>
37 #include <linux/of.h>
38 #include <linux/platform_data/leds-pca963x.h>
39
40 /* LED select registers determine the source that drives LED outputs */
41 #define PCA963X_LED_OFF 0x0 /* LED driver off */
42 #define PCA963X_LED_ON 0x1 /* LED driver on */
43 #define PCA963X_LED_PWM 0x2 /* Controlled through PWM */
44 #define PCA963X_LED_GRP_PWM 0x3 /* Controlled through PWM/GRPPWM */
45
46 #define PCA963X_MODE2_DMBLNK 0x20 /* Enable blinking */
47
48 #define PCA963X_MODE1 0x00
49 #define PCA963X_MODE2 0x01
50 #define PCA963X_PWM_BASE 0x02
51
52 enum pca963x_type {
53 pca9633,
54 pca9634,
55 };
56
57 struct pca963x_chipdef {
58 u8 grppwm;
59 u8 grpfreq;
60 u8 ledout_base;
61 int n_leds;
62 };
63
64 static struct pca963x_chipdef pca963x_chipdefs[] = {
65 [pca9633] = {
66 .grppwm = 0x6,
67 .grpfreq = 0x7,
68 .ledout_base = 0x8,
69 .n_leds = 4,
70 },
71 [pca9634] = {
72 .grppwm = 0xa,
73 .grpfreq = 0xb,
74 .ledout_base = 0xc,
75 .n_leds = 8,
76 },
77 };
78
79 /* Total blink period in milliseconds */
80 #define PCA963X_BLINK_PERIOD_MIN 42
81 #define PCA963X_BLINK_PERIOD_MAX 10667
82
83 static const struct i2c_device_id pca963x_id[] = {
84 { "pca9632", pca9633 },
85 { "pca9633", pca9633 },
86 { "pca9634", pca9634 },
87 { }
88 };
89 MODULE_DEVICE_TABLE(i2c, pca963x_id);
90
91 enum pca963x_cmd {
92 BRIGHTNESS_SET,
93 BLINK_SET,
94 };
95
96 struct pca963x_led;
97
98 struct pca963x {
99 struct pca963x_chipdef *chipdef;
100 struct mutex mutex;
101 struct i2c_client *client;
102 struct pca963x_led *leds;
103 };
104
105 struct pca963x_led {
106 struct pca963x *chip;
107 struct work_struct work;
108 enum led_brightness brightness;
109 struct led_classdev led_cdev;
110 int led_num; /* 0 .. 7 potentially */
111 enum pca963x_cmd cmd;
112 char name[32];
113 u8 gdc;
114 u8 gfrq;
115 };
116
117 static void pca963x_brightness_work(struct pca963x_led *pca963x)
118 {
119 u8 ledout_addr = pca963x->chip->chipdef->ledout_base
120 + (pca963x->led_num / 4);
121 u8 ledout;
122 int shift = 2 * (pca963x->led_num % 4);
123 u8 mask = 0x3 << shift;
124
125 mutex_lock(&pca963x->chip->mutex);
126 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr);
127 switch (pca963x->brightness) {
128 case LED_FULL:
129 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
130 (ledout & ~mask) | (PCA963X_LED_ON << shift));
131 break;
132 case LED_OFF:
133 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
134 ledout & ~mask);
135 break;
136 default:
137 i2c_smbus_write_byte_data(pca963x->chip->client,
138 PCA963X_PWM_BASE + pca963x->led_num,
139 pca963x->brightness);
140 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
141 (ledout & ~mask) | (PCA963X_LED_PWM << shift));
142 break;
143 }
144 mutex_unlock(&pca963x->chip->mutex);
145 }
146
147 static void pca963x_blink_work(struct pca963x_led *pca963x)
148 {
149 u8 ledout_addr = pca963x->chip->chipdef->ledout_base +
150 (pca963x->led_num / 4);
151 u8 ledout;
152 u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client,
153 PCA963X_MODE2);
154 int shift = 2 * (pca963x->led_num % 4);
155 u8 mask = 0x3 << shift;
156
157 i2c_smbus_write_byte_data(pca963x->chip->client,
158 pca963x->chip->chipdef->grppwm, pca963x->gdc);
159
160 i2c_smbus_write_byte_data(pca963x->chip->client,
161 pca963x->chip->chipdef->grpfreq, pca963x->gfrq);
162
163 if (!(mode2 & PCA963X_MODE2_DMBLNK))
164 i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2,
165 mode2 | PCA963X_MODE2_DMBLNK);
166
167 mutex_lock(&pca963x->chip->mutex);
168 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr);
169 if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift))
170 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
171 (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift));
172 mutex_unlock(&pca963x->chip->mutex);
173 }
174
175 static void pca963x_work(struct work_struct *work)
176 {
177 struct pca963x_led *pca963x = container_of(work,
178 struct pca963x_led, work);
179
180 switch (pca963x->cmd) {
181 case BRIGHTNESS_SET:
182 pca963x_brightness_work(pca963x);
183 break;
184 case BLINK_SET:
185 pca963x_blink_work(pca963x);
186 break;
187 }
188 }
189
190 static void pca963x_led_set(struct led_classdev *led_cdev,
191 enum led_brightness value)
192 {
193 struct pca963x_led *pca963x;
194
195 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev);
196
197 pca963x->cmd = BRIGHTNESS_SET;
198 pca963x->brightness = value;
199
200 /*
201 * Must use workqueue for the actual I/O since I2C operations
202 * can sleep.
203 */
204 schedule_work(&pca963x->work);
205 }
206
207 static int pca963x_blink_set(struct led_classdev *led_cdev,
208 unsigned long *delay_on, unsigned long *delay_off)
209 {
210 struct pca963x_led *pca963x;
211 unsigned long time_on, time_off, period;
212 u8 gdc, gfrq;
213
214 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev);
215
216 time_on = *delay_on;
217 time_off = *delay_off;
218
219 /* If both zero, pick reasonable defaults of 500ms each */
220 if (!time_on && !time_off) {
221 time_on = 500;
222 time_off = 500;
223 }
224
225 period = time_on + time_off;
226
227 /* If period not supported by hardware, default to someting sane. */
228 if ((period < PCA963X_BLINK_PERIOD_MIN) ||
229 (period > PCA963X_BLINK_PERIOD_MAX)) {
230 time_on = 500;
231 time_off = 500;
232 period = time_on + time_off;
233 }
234
235 /*
236 * From manual: duty cycle = (GDC / 256) ->
237 * (time_on / period) = (GDC / 256) ->
238 * GDC = ((time_on * 256) / period)
239 */
240 gdc = (time_on * 256) / period;
241
242 /*
243 * From manual: period = ((GFRQ + 1) / 24) in seconds.
244 * So, period (in ms) = (((GFRQ + 1) / 24) * 1000) ->
245 * GFRQ = ((period * 24 / 1000) - 1)
246 */
247 gfrq = (period * 24 / 1000) - 1;
248
249 pca963x->cmd = BLINK_SET;
250 pca963x->gdc = gdc;
251 pca963x->gfrq = gfrq;
252
253 /*
254 * Must use workqueue for the actual I/O since I2C operations
255 * can sleep.
256 */
257 schedule_work(&pca963x->work);
258
259 *delay_on = time_on;
260 *delay_off = time_off;
261
262 return 0;
263 }
264
265 #if IS_ENABLED(CONFIG_OF)
266 static struct pca963x_platform_data *
267 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip)
268 {
269 struct device_node *np = client->dev.of_node, *child;
270 struct pca963x_platform_data *pdata;
271 struct led_info *pca963x_leds;
272 int count;
273
274 count = of_get_child_count(np);
275 if (!count || count > chip->n_leds)
276 return ERR_PTR(-ENODEV);
277
278 pca963x_leds = devm_kzalloc(&client->dev,
279 sizeof(struct led_info) * chip->n_leds, GFP_KERNEL);
280 if (!pca963x_leds)
281 return ERR_PTR(-ENOMEM);
282
283 for_each_child_of_node(np, child) {
284 struct led_info led;
285 u32 reg;
286 int res;
287
288 res = of_property_read_u32(child, "reg", &reg);
289 if ((res != 0) || (reg >= chip->n_leds))
290 continue;
291 led.name =
292 of_get_property(child, "label", NULL) ? : child->name;
293 led.default_trigger =
294 of_get_property(child, "linux,default-trigger", NULL);
295 pca963x_leds[reg] = led;
296 }
297 pdata = devm_kzalloc(&client->dev,
298 sizeof(struct pca963x_platform_data), GFP_KERNEL);
299 if (!pdata)
300 return ERR_PTR(-ENOMEM);
301
302 pdata->leds.leds = pca963x_leds;
303 pdata->leds.num_leds = chip->n_leds;
304
305 /* default to open-drain unless totem pole (push-pull) is specified */
306 if (of_property_read_bool(np, "nxp,totem-pole"))
307 pdata->outdrv = PCA963X_TOTEM_POLE;
308 else
309 pdata->outdrv = PCA963X_OPEN_DRAIN;
310
311 /* default to software blinking unless hardware blinking is specified */
312 if (of_property_read_bool(np, "nxp,hw-blink"))
313 pdata->blink_type = PCA963X_HW_BLINK;
314 else
315 pdata->blink_type = PCA963X_SW_BLINK;
316
317 return pdata;
318 }
319
320 static const struct of_device_id of_pca963x_match[] = {
321 { .compatible = "nxp,pca9632", },
322 { .compatible = "nxp,pca9633", },
323 { .compatible = "nxp,pca9634", },
324 {},
325 };
326 #else
327 static struct pca963x_platform_data *
328 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip)
329 {
330 return ERR_PTR(-ENODEV);
331 }
332 #endif
333
334 static int pca963x_probe(struct i2c_client *client,
335 const struct i2c_device_id *id)
336 {
337 struct pca963x *pca963x_chip;
338 struct pca963x_led *pca963x;
339 struct pca963x_platform_data *pdata;
340 struct pca963x_chipdef *chip;
341 int i, err;
342
343 chip = &pca963x_chipdefs[id->driver_data];
344 pdata = dev_get_platdata(&client->dev);
345
346 if (!pdata) {
347 pdata = pca963x_dt_init(client, chip);
348 if (IS_ERR(pdata)) {
349 dev_warn(&client->dev, "could not parse configuration\n");
350 pdata = NULL;
351 }
352 }
353
354 if (pdata && (pdata->leds.num_leds < 1 ||
355 pdata->leds.num_leds > chip->n_leds)) {
356 dev_err(&client->dev, "board info must claim 1-%d LEDs",
357 chip->n_leds);
358 return -EINVAL;
359 }
360
361 pca963x_chip = devm_kzalloc(&client->dev, sizeof(*pca963x_chip),
362 GFP_KERNEL);
363 if (!pca963x_chip)
364 return -ENOMEM;
365 pca963x = devm_kzalloc(&client->dev, chip->n_leds * sizeof(*pca963x),
366 GFP_KERNEL);
367 if (!pca963x)
368 return -ENOMEM;
369
370 i2c_set_clientdata(client, pca963x_chip);
371
372 mutex_init(&pca963x_chip->mutex);
373 pca963x_chip->chipdef = chip;
374 pca963x_chip->client = client;
375 pca963x_chip->leds = pca963x;
376
377 /* Turn off LEDs by default*/
378 i2c_smbus_write_byte_data(client, chip->ledout_base, 0x00);
379 if (chip->n_leds > 4)
380 i2c_smbus_write_byte_data(client, chip->ledout_base + 1, 0x00);
381
382 for (i = 0; i < chip->n_leds; i++) {
383 pca963x[i].led_num = i;
384 pca963x[i].chip = pca963x_chip;
385
386 /* Platform data can specify LED names and default triggers */
387 if (pdata && i < pdata->leds.num_leds) {
388 if (pdata->leds.leds[i].name)
389 snprintf(pca963x[i].name,
390 sizeof(pca963x[i].name), "pca963x:%s",
391 pdata->leds.leds[i].name);
392 if (pdata->leds.leds[i].default_trigger)
393 pca963x[i].led_cdev.default_trigger =
394 pdata->leds.leds[i].default_trigger;
395 }
396 if (!pdata || i >= pdata->leds.num_leds ||
397 !pdata->leds.leds[i].name)
398 snprintf(pca963x[i].name, sizeof(pca963x[i].name),
399 "pca963x:%d:%.2x:%d", client->adapter->nr,
400 client->addr, i);
401
402 pca963x[i].led_cdev.name = pca963x[i].name;
403 pca963x[i].led_cdev.brightness_set = pca963x_led_set;
404
405 if (pdata && pdata->blink_type == PCA963X_HW_BLINK)
406 pca963x[i].led_cdev.blink_set = pca963x_blink_set;
407
408 INIT_WORK(&pca963x[i].work, pca963x_work);
409
410 err = led_classdev_register(&client->dev, &pca963x[i].led_cdev);
411 if (err < 0)
412 goto exit;
413 }
414
415 /* Disable LED all-call address and set normal mode */
416 i2c_smbus_write_byte_data(client, PCA963X_MODE1, 0x00);
417
418 /* Configure output: open-drain or totem pole (push-pull) */
419 if (pdata && pdata->outdrv == PCA963X_OPEN_DRAIN)
420 i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x01);
421
422 return 0;
423
424 exit:
425 while (i--) {
426 led_classdev_unregister(&pca963x[i].led_cdev);
427 cancel_work_sync(&pca963x[i].work);
428 }
429
430 return err;
431 }
432
433 static int pca963x_remove(struct i2c_client *client)
434 {
435 struct pca963x *pca963x = i2c_get_clientdata(client);
436 int i;
437
438 for (i = 0; i < pca963x->chipdef->n_leds; i++) {
439 led_classdev_unregister(&pca963x->leds[i].led_cdev);
440 cancel_work_sync(&pca963x->leds[i].work);
441 }
442
443 return 0;
444 }
445
446 static struct i2c_driver pca963x_driver = {
447 .driver = {
448 .name = "leds-pca963x",
449 .owner = THIS_MODULE,
450 .of_match_table = of_match_ptr(of_pca963x_match),
451 },
452 .probe = pca963x_probe,
453 .remove = pca963x_remove,
454 .id_table = pca963x_id,
455 };
456
457 module_i2c_driver(pca963x_driver);
458
459 MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>");
460 MODULE_DESCRIPTION("PCA963X LED driver");
461 MODULE_LICENSE("GPL v2");
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