Merge remote-tracking branches 'spi/fix/atmel', 'spi/fix/bcm2835', 'spi/fix/doc'...
[firefly-linux-kernel-4.4.55.git] / drivers / leds / leds-pca963x.c
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 PCA9634/5 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         pca9635,
56 };
57
58 struct pca963x_chipdef {
59         u8                      grppwm;
60         u8                      grpfreq;
61         u8                      ledout_base;
62         int                     n_leds;
63 };
64
65 static struct pca963x_chipdef pca963x_chipdefs[] = {
66         [pca9633] = {
67                 .grppwm         = 0x6,
68                 .grpfreq        = 0x7,
69                 .ledout_base    = 0x8,
70                 .n_leds         = 4,
71         },
72         [pca9634] = {
73                 .grppwm         = 0xa,
74                 .grpfreq        = 0xb,
75                 .ledout_base    = 0xc,
76                 .n_leds         = 8,
77         },
78         [pca9635] = {
79                 .grppwm         = 0x12,
80                 .grpfreq        = 0x13,
81                 .ledout_base    = 0x14,
82                 .n_leds         = 16,
83         },
84 };
85
86 /* Total blink period in milliseconds */
87 #define PCA963X_BLINK_PERIOD_MIN        42
88 #define PCA963X_BLINK_PERIOD_MAX        10667
89
90 static const struct i2c_device_id pca963x_id[] = {
91         { "pca9632", pca9633 },
92         { "pca9633", pca9633 },
93         { "pca9634", pca9634 },
94         { "pca9635", pca9635 },
95         { }
96 };
97 MODULE_DEVICE_TABLE(i2c, pca963x_id);
98
99 enum pca963x_cmd {
100         BRIGHTNESS_SET,
101         BLINK_SET,
102 };
103
104 struct pca963x_led;
105
106 struct pca963x {
107         struct pca963x_chipdef *chipdef;
108         struct mutex mutex;
109         struct i2c_client *client;
110         struct pca963x_led *leds;
111 };
112
113 struct pca963x_led {
114         struct pca963x *chip;
115         struct work_struct work;
116         enum led_brightness brightness;
117         struct led_classdev led_cdev;
118         int led_num; /* 0 .. 15 potentially */
119         enum pca963x_cmd cmd;
120         char name[32];
121         u8 gdc;
122         u8 gfrq;
123 };
124
125 static void pca963x_brightness_work(struct pca963x_led *pca963x)
126 {
127         u8 ledout_addr = pca963x->chip->chipdef->ledout_base
128                 + (pca963x->led_num / 4);
129         u8 ledout;
130         int shift = 2 * (pca963x->led_num % 4);
131         u8 mask = 0x3 << shift;
132
133         mutex_lock(&pca963x->chip->mutex);
134         ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr);
135         switch (pca963x->brightness) {
136         case LED_FULL:
137                 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
138                         (ledout & ~mask) | (PCA963X_LED_ON << shift));
139                 break;
140         case LED_OFF:
141                 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
142                         ledout & ~mask);
143                 break;
144         default:
145                 i2c_smbus_write_byte_data(pca963x->chip->client,
146                         PCA963X_PWM_BASE + pca963x->led_num,
147                         pca963x->brightness);
148                 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
149                         (ledout & ~mask) | (PCA963X_LED_PWM << shift));
150                 break;
151         }
152         mutex_unlock(&pca963x->chip->mutex);
153 }
154
155 static void pca963x_blink_work(struct pca963x_led *pca963x)
156 {
157         u8 ledout_addr = pca963x->chip->chipdef->ledout_base +
158                 (pca963x->led_num / 4);
159         u8 ledout;
160         u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client,
161                                                         PCA963X_MODE2);
162         int shift = 2 * (pca963x->led_num % 4);
163         u8 mask = 0x3 << shift;
164
165         i2c_smbus_write_byte_data(pca963x->chip->client,
166                         pca963x->chip->chipdef->grppwm, pca963x->gdc);
167
168         i2c_smbus_write_byte_data(pca963x->chip->client,
169                         pca963x->chip->chipdef->grpfreq, pca963x->gfrq);
170
171         if (!(mode2 & PCA963X_MODE2_DMBLNK))
172                 i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2,
173                         mode2 | PCA963X_MODE2_DMBLNK);
174
175         mutex_lock(&pca963x->chip->mutex);
176         ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr);
177         if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift))
178                 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr,
179                         (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift));
180         mutex_unlock(&pca963x->chip->mutex);
181 }
182
183 static void pca963x_work(struct work_struct *work)
184 {
185         struct pca963x_led *pca963x = container_of(work,
186                 struct pca963x_led, work);
187
188         switch (pca963x->cmd) {
189         case BRIGHTNESS_SET:
190                 pca963x_brightness_work(pca963x);
191                 break;
192         case BLINK_SET:
193                 pca963x_blink_work(pca963x);
194                 break;
195         }
196 }
197
198 static void pca963x_led_set(struct led_classdev *led_cdev,
199         enum led_brightness value)
200 {
201         struct pca963x_led *pca963x;
202
203         pca963x = container_of(led_cdev, struct pca963x_led, led_cdev);
204
205         pca963x->cmd = BRIGHTNESS_SET;
206         pca963x->brightness = value;
207
208         /*
209          * Must use workqueue for the actual I/O since I2C operations
210          * can sleep.
211          */
212         schedule_work(&pca963x->work);
213 }
214
215 static int pca963x_blink_set(struct led_classdev *led_cdev,
216                 unsigned long *delay_on, unsigned long *delay_off)
217 {
218         struct pca963x_led *pca963x;
219         unsigned long time_on, time_off, period;
220         u8 gdc, gfrq;
221
222         pca963x = container_of(led_cdev, struct pca963x_led, led_cdev);
223
224         time_on = *delay_on;
225         time_off = *delay_off;
226
227         /* If both zero, pick reasonable defaults of 500ms each */
228         if (!time_on && !time_off) {
229                 time_on = 500;
230                 time_off = 500;
231         }
232
233         period = time_on + time_off;
234
235         /* If period not supported by hardware, default to someting sane. */
236         if ((period < PCA963X_BLINK_PERIOD_MIN) ||
237             (period > PCA963X_BLINK_PERIOD_MAX)) {
238                 time_on = 500;
239                 time_off = 500;
240                 period = time_on + time_off;
241         }
242
243         /*
244          * From manual: duty cycle = (GDC / 256) ->
245          *      (time_on / period) = (GDC / 256) ->
246          *              GDC = ((time_on * 256) / period)
247          */
248         gdc = (time_on * 256) / period;
249
250         /*
251          * From manual: period = ((GFRQ + 1) / 24) in seconds.
252          * So, period (in ms) = (((GFRQ + 1) / 24) * 1000) ->
253          *              GFRQ = ((period * 24 / 1000) - 1)
254          */
255         gfrq = (period * 24 / 1000) - 1;
256
257         pca963x->cmd = BLINK_SET;
258         pca963x->gdc = gdc;
259         pca963x->gfrq = gfrq;
260
261         /*
262          * Must use workqueue for the actual I/O since I2C operations
263          * can sleep.
264          */
265         schedule_work(&pca963x->work);
266
267         *delay_on = time_on;
268         *delay_off = time_off;
269
270         return 0;
271 }
272
273 #if IS_ENABLED(CONFIG_OF)
274 static struct pca963x_platform_data *
275 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip)
276 {
277         struct device_node *np = client->dev.of_node, *child;
278         struct pca963x_platform_data *pdata;
279         struct led_info *pca963x_leds;
280         int count;
281
282         count = of_get_child_count(np);
283         if (!count || count > chip->n_leds)
284                 return ERR_PTR(-ENODEV);
285
286         pca963x_leds = devm_kzalloc(&client->dev,
287                         sizeof(struct led_info) * chip->n_leds, GFP_KERNEL);
288         if (!pca963x_leds)
289                 return ERR_PTR(-ENOMEM);
290
291         for_each_child_of_node(np, child) {
292                 struct led_info led = {};
293                 u32 reg;
294                 int res;
295
296                 res = of_property_read_u32(child, "reg", &reg);
297                 if ((res != 0) || (reg >= chip->n_leds))
298                         continue;
299                 led.name =
300                         of_get_property(child, "label", NULL) ? : child->name;
301                 led.default_trigger =
302                         of_get_property(child, "linux,default-trigger", NULL);
303                 pca963x_leds[reg] = led;
304         }
305         pdata = devm_kzalloc(&client->dev,
306                              sizeof(struct pca963x_platform_data), GFP_KERNEL);
307         if (!pdata)
308                 return ERR_PTR(-ENOMEM);
309
310         pdata->leds.leds = pca963x_leds;
311         pdata->leds.num_leds = chip->n_leds;
312
313         /* default to open-drain unless totem pole (push-pull) is specified */
314         if (of_property_read_bool(np, "nxp,totem-pole"))
315                 pdata->outdrv = PCA963X_TOTEM_POLE;
316         else
317                 pdata->outdrv = PCA963X_OPEN_DRAIN;
318
319         /* default to software blinking unless hardware blinking is specified */
320         if (of_property_read_bool(np, "nxp,hw-blink"))
321                 pdata->blink_type = PCA963X_HW_BLINK;
322         else
323                 pdata->blink_type = PCA963X_SW_BLINK;
324
325         return pdata;
326 }
327
328 static const struct of_device_id of_pca963x_match[] = {
329         { .compatible = "nxp,pca9632", },
330         { .compatible = "nxp,pca9633", },
331         { .compatible = "nxp,pca9634", },
332         { .compatible = "nxp,pca9635", },
333         {},
334 };
335 MODULE_DEVICE_TABLE(of, of_pca963x_match);
336 #else
337 static struct pca963x_platform_data *
338 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip)
339 {
340         return ERR_PTR(-ENODEV);
341 }
342 #endif
343
344 static int pca963x_probe(struct i2c_client *client,
345                                         const struct i2c_device_id *id)
346 {
347         struct pca963x *pca963x_chip;
348         struct pca963x_led *pca963x;
349         struct pca963x_platform_data *pdata;
350         struct pca963x_chipdef *chip;
351         int i, err;
352
353         chip = &pca963x_chipdefs[id->driver_data];
354         pdata = dev_get_platdata(&client->dev);
355
356         if (!pdata) {
357                 pdata = pca963x_dt_init(client, chip);
358                 if (IS_ERR(pdata)) {
359                         dev_warn(&client->dev, "could not parse configuration\n");
360                         pdata = NULL;
361                 }
362         }
363
364         if (pdata && (pdata->leds.num_leds < 1 ||
365                                  pdata->leds.num_leds > chip->n_leds)) {
366                 dev_err(&client->dev, "board info must claim 1-%d LEDs",
367                                                                 chip->n_leds);
368                 return -EINVAL;
369         }
370
371         pca963x_chip = devm_kzalloc(&client->dev, sizeof(*pca963x_chip),
372                                                                 GFP_KERNEL);
373         if (!pca963x_chip)
374                 return -ENOMEM;
375         pca963x = devm_kzalloc(&client->dev, chip->n_leds * sizeof(*pca963x),
376                                                                 GFP_KERNEL);
377         if (!pca963x)
378                 return -ENOMEM;
379
380         i2c_set_clientdata(client, pca963x_chip);
381
382         mutex_init(&pca963x_chip->mutex);
383         pca963x_chip->chipdef = chip;
384         pca963x_chip->client = client;
385         pca963x_chip->leds = pca963x;
386
387         /* Turn off LEDs by default*/
388         for (i = 0; i < chip->n_leds / 4; i++)
389                 i2c_smbus_write_byte_data(client, chip->ledout_base + i, 0x00);
390
391         for (i = 0; i < chip->n_leds; i++) {
392                 pca963x[i].led_num = i;
393                 pca963x[i].chip = pca963x_chip;
394
395                 /* Platform data can specify LED names and default triggers */
396                 if (pdata && i < pdata->leds.num_leds) {
397                         if (pdata->leds.leds[i].name)
398                                 snprintf(pca963x[i].name,
399                                          sizeof(pca963x[i].name), "pca963x:%s",
400                                          pdata->leds.leds[i].name);
401                         if (pdata->leds.leds[i].default_trigger)
402                                 pca963x[i].led_cdev.default_trigger =
403                                         pdata->leds.leds[i].default_trigger;
404                 }
405                 if (!pdata || i >= pdata->leds.num_leds ||
406                                                 !pdata->leds.leds[i].name)
407                         snprintf(pca963x[i].name, sizeof(pca963x[i].name),
408                                  "pca963x:%d:%.2x:%d", client->adapter->nr,
409                                  client->addr, i);
410
411                 pca963x[i].led_cdev.name = pca963x[i].name;
412                 pca963x[i].led_cdev.brightness_set = pca963x_led_set;
413
414                 if (pdata && pdata->blink_type == PCA963X_HW_BLINK)
415                         pca963x[i].led_cdev.blink_set = pca963x_blink_set;
416
417                 INIT_WORK(&pca963x[i].work, pca963x_work);
418
419                 err = led_classdev_register(&client->dev, &pca963x[i].led_cdev);
420                 if (err < 0)
421                         goto exit;
422         }
423
424         /* Disable LED all-call address and set normal mode */
425         i2c_smbus_write_byte_data(client, PCA963X_MODE1, 0x00);
426
427         if (pdata) {
428                 /* Configure output: open-drain or totem pole (push-pull) */
429                 if (pdata->outdrv == PCA963X_OPEN_DRAIN)
430                         i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x01);
431                 else
432                         i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x05);
433         }
434
435         return 0;
436
437 exit:
438         while (i--) {
439                 led_classdev_unregister(&pca963x[i].led_cdev);
440                 cancel_work_sync(&pca963x[i].work);
441         }
442
443         return err;
444 }
445
446 static int pca963x_remove(struct i2c_client *client)
447 {
448         struct pca963x *pca963x = i2c_get_clientdata(client);
449         int i;
450
451         for (i = 0; i < pca963x->chipdef->n_leds; i++) {
452                 led_classdev_unregister(&pca963x->leds[i].led_cdev);
453                 cancel_work_sync(&pca963x->leds[i].work);
454         }
455
456         return 0;
457 }
458
459 static struct i2c_driver pca963x_driver = {
460         .driver = {
461                 .name   = "leds-pca963x",
462                 .of_match_table = of_match_ptr(of_pca963x_match),
463         },
464         .probe  = pca963x_probe,
465         .remove = pca963x_remove,
466         .id_table = pca963x_id,
467 };
468
469 module_i2c_driver(pca963x_driver);
470
471 MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>");
472 MODULE_DESCRIPTION("PCA963X LED driver");
473 MODULE_LICENSE("GPL v2");