1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2011 bct electronic GmbH
4 * Copyright 2013 Qtechnology/AS
5 *
6 * Author: Peter Meerwald <p.meerwald@bct-electronic.com>
7 * Author: Ricardo Ribalda <ribalda@kernel.org>
8 *
9 * Based on leds-pca955x.c
10 *
11 * LED driver for the PCA9633 I2C LED driver (7-bit slave address 0x62)
12 * LED driver for the PCA9634/5 I2C LED driver (7-bit slave address set by hw.)
13 *
14 * Note that hardware blinking violates the leds infrastructure driver
15 * interface since the hardware only supports blinking all LEDs with the
16 * same delay_on/delay_off rates. That is, only the LEDs that are set to
17 * blink will actually blink but all LEDs that are set to blink will blink
18 * in identical fashion. The delay_on/delay_off values of the last LED
19 * that is set to blink will be used for all of the blinking LEDs.
20 * Hardware blinking is disabled by default but can be enabled by setting
21 * the 'blink_type' member in the platform_data struct to 'PCA963X_HW_BLINK'
22 * or by adding the 'nxp,hw-blink' property to the DTS.
23 */
24
25#include <linux/module.h>
26#include <linux/delay.h>
27#include <linux/string.h>
28#include <linux/ctype.h>
29#include <linux/leds.h>
30#include <linux/err.h>
31#include <linux/i2c.h>
32#include <linux/property.h>
33#include <linux/slab.h>
34#include <linux/of.h>
35
36/* LED select registers determine the source that drives LED outputs */
37#define PCA963X_LED_OFF 0x0 /* LED driver off */
38#define PCA963X_LED_ON 0x1 /* LED driver on */
39#define PCA963X_LED_PWM 0x2 /* Controlled through PWM */
40#define PCA963X_LED_GRP_PWM 0x3 /* Controlled through PWM/GRPPWM */
41
42#define PCA963X_MODE1_SLEEP 0x04 /* Normal mode or Low Power mode, oscillator off */
43#define PCA963X_MODE2_OUTDRV 0x04 /* Open-drain or totem pole */
44#define PCA963X_MODE2_INVRT 0x10 /* Normal or inverted direction */
45#define PCA963X_MODE2_DMBLNK 0x20 /* Enable blinking */
46
47#define PCA963X_MODE1 0x00
48#define PCA963X_MODE2 0x01
49#define PCA963X_PWM_BASE 0x02
50
51enum pca963x_type {
52 pca9633,
53 pca9634,
54 pca9635,
55};
56
57struct pca963x_chipdef {
58 u8 grppwm;
59 u8 grpfreq;
60 u8 ledout_base;
61 int n_leds;
62 unsigned int scaling;
63};
64
65static 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
90static const struct i2c_device_id pca963x_id[] = {
91 { "pca9632", pca9633 },
92 { "pca9633", pca9633 },
93 { "pca9634", pca9634 },
94 { "pca9635", pca9635 },
95 { }
96};
97MODULE_DEVICE_TABLE(i2c, pca963x_id);
98
99struct pca963x;
100
101struct pca963x_led {
102 struct pca963x *chip;
103 struct led_classdev led_cdev;
104 int led_num; /* 0 .. 15 potentially */
105 bool blinking;
106 u8 gdc;
107 u8 gfrq;
108};
109
110struct pca963x {
111 struct pca963x_chipdef *chipdef;
112 struct mutex mutex;
113 struct i2c_client *client;
114 unsigned long leds_on;
115 struct pca963x_led leds[];
116};
117
118static int pca963x_brightness(struct pca963x_led *led,
119 enum led_brightness brightness)
120{
121 struct i2c_client *client = led->chip->client;
122 struct pca963x_chipdef *chipdef = led->chip->chipdef;
123 u8 ledout_addr, ledout, mask, val;
124 int shift;
125 int ret;
126
127 ledout_addr = chipdef->ledout_base + (led->led_num / 4);
128 shift = 2 * (led->led_num % 4);
129 mask = 0x3 << shift;
130 ledout = i2c_smbus_read_byte_data(client, command: ledout_addr);
131
132 switch (brightness) {
133 case LED_FULL:
134 if (led->blinking) {
135 val = (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift);
136 ret = i2c_smbus_write_byte_data(client,
137 PCA963X_PWM_BASE +
138 led->led_num,
139 value: LED_FULL);
140 } else {
141 val = (ledout & ~mask) | (PCA963X_LED_ON << shift);
142 }
143 ret = i2c_smbus_write_byte_data(client, command: ledout_addr, value: val);
144 break;
145 case LED_OFF:
146 val = ledout & ~mask;
147 ret = i2c_smbus_write_byte_data(client, command: ledout_addr, value: val);
148 led->blinking = false;
149 break;
150 default:
151 ret = i2c_smbus_write_byte_data(client,
152 PCA963X_PWM_BASE +
153 led->led_num,
154 value: brightness);
155 if (ret < 0)
156 return ret;
157
158 if (led->blinking)
159 val = (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift);
160 else
161 val = (ledout & ~mask) | (PCA963X_LED_PWM << shift);
162
163 ret = i2c_smbus_write_byte_data(client, command: ledout_addr, value: val);
164 break;
165 }
166
167 return ret;
168}
169
170static void pca963x_blink(struct pca963x_led *led)
171{
172 struct i2c_client *client = led->chip->client;
173 struct pca963x_chipdef *chipdef = led->chip->chipdef;
174 u8 ledout_addr, ledout, mask, val, mode2;
175 int shift;
176
177 ledout_addr = chipdef->ledout_base + (led->led_num / 4);
178 shift = 2 * (led->led_num % 4);
179 mask = 0x3 << shift;
180 mode2 = i2c_smbus_read_byte_data(client, PCA963X_MODE2);
181
182 i2c_smbus_write_byte_data(client, command: chipdef->grppwm, value: led->gdc);
183
184 i2c_smbus_write_byte_data(client, command: chipdef->grpfreq, value: led->gfrq);
185
186 if (!(mode2 & PCA963X_MODE2_DMBLNK))
187 i2c_smbus_write_byte_data(client, PCA963X_MODE2,
188 value: mode2 | PCA963X_MODE2_DMBLNK);
189
190 mutex_lock(&led->chip->mutex);
191
192 ledout = i2c_smbus_read_byte_data(client, command: ledout_addr);
193 if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift)) {
194 val = (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift);
195 i2c_smbus_write_byte_data(client, command: ledout_addr, value: val);
196 }
197
198 mutex_unlock(lock: &led->chip->mutex);
199 led->blinking = true;
200}
201
202static int pca963x_power_state(struct pca963x_led *led)
203{
204 struct i2c_client *client = led->chip->client;
205 unsigned long *leds_on = &led->chip->leds_on;
206 unsigned long cached_leds = *leds_on;
207
208 if (led->led_cdev.brightness)
209 set_bit(nr: led->led_num, addr: leds_on);
210 else
211 clear_bit(nr: led->led_num, addr: leds_on);
212
213 if (!(*leds_on) != !cached_leds)
214 return i2c_smbus_write_byte_data(client, PCA963X_MODE1,
215 value: *leds_on ? 0 : BIT(4));
216
217 return 0;
218}
219
220static int pca963x_led_set(struct led_classdev *led_cdev,
221 enum led_brightness value)
222{
223 struct pca963x_led *led;
224 int ret;
225
226 led = container_of(led_cdev, struct pca963x_led, led_cdev);
227
228 mutex_lock(&led->chip->mutex);
229
230 ret = pca963x_brightness(led, brightness: value);
231 if (ret < 0)
232 goto unlock;
233 ret = pca963x_power_state(led);
234
235unlock:
236 mutex_unlock(lock: &led->chip->mutex);
237 return ret;
238}
239
240static unsigned int pca963x_period_scale(struct pca963x_led *led,
241 unsigned int val)
242{
243 unsigned int scaling = led->chip->chipdef->scaling;
244
245 return scaling ? DIV_ROUND_CLOSEST(val * scaling, 1000) : val;
246}
247
248static int pca963x_blink_set(struct led_classdev *led_cdev,
249 unsigned long *delay_on, unsigned long *delay_off)
250{
251 unsigned long time_on, time_off, period;
252 struct pca963x_led *led;
253 u8 gdc, gfrq;
254
255 led = container_of(led_cdev, struct pca963x_led, led_cdev);
256
257 time_on = *delay_on;
258 time_off = *delay_off;
259
260 /* If both zero, pick reasonable defaults of 500ms each */
261 if (!time_on && !time_off) {
262 time_on = 500;
263 time_off = 500;
264 }
265
266 period = pca963x_period_scale(led, val: time_on + time_off);
267
268 /* If period not supported by hardware, default to someting sane. */
269 if ((period < PCA963X_BLINK_PERIOD_MIN) ||
270 (period > PCA963X_BLINK_PERIOD_MAX)) {
271 time_on = 500;
272 time_off = 500;
273 period = pca963x_period_scale(led, val: 1000);
274 }
275
276 /*
277 * From manual: duty cycle = (GDC / 256) ->
278 * (time_on / period) = (GDC / 256) ->
279 * GDC = ((time_on * 256) / period)
280 */
281 gdc = (pca963x_period_scale(led, val: time_on) * 256) / period;
282
283 /*
284 * From manual: period = ((GFRQ + 1) / 24) in seconds.
285 * So, period (in ms) = (((GFRQ + 1) / 24) * 1000) ->
286 * GFRQ = ((period * 24 / 1000) - 1)
287 */
288 gfrq = (period * 24 / 1000) - 1;
289
290 led->gdc = gdc;
291 led->gfrq = gfrq;
292
293 pca963x_blink(led);
294 led->led_cdev.brightness = LED_FULL;
295 pca963x_led_set(led_cdev, value: LED_FULL);
296
297 *delay_on = time_on;
298 *delay_off = time_off;
299
300 return 0;
301}
302
303static int pca963x_register_leds(struct i2c_client *client,
304 struct pca963x *chip)
305{
306 struct pca963x_chipdef *chipdef = chip->chipdef;
307 struct pca963x_led *led = chip->leds;
308 struct device *dev = &client->dev;
309 bool hw_blink;
310 s32 mode2;
311 u32 reg;
312 int ret;
313
314 if (device_property_read_u32(dev, propname: "nxp,period-scale",
315 val: &chipdef->scaling))
316 chipdef->scaling = 1000;
317
318 hw_blink = device_property_read_bool(dev, propname: "nxp,hw-blink");
319
320 mode2 = i2c_smbus_read_byte_data(client, PCA963X_MODE2);
321 if (mode2 < 0)
322 return mode2;
323
324 /* default to open-drain unless totem pole (push-pull) is specified */
325 if (device_property_read_bool(dev, propname: "nxp,totem-pole"))
326 mode2 |= PCA963X_MODE2_OUTDRV;
327 else
328 mode2 &= ~PCA963X_MODE2_OUTDRV;
329
330 /* default to non-inverted output, unless inverted is specified */
331 if (device_property_read_bool(dev, propname: "nxp,inverted-out"))
332 mode2 |= PCA963X_MODE2_INVRT;
333 else
334 mode2 &= ~PCA963X_MODE2_INVRT;
335
336 ret = i2c_smbus_write_byte_data(client, PCA963X_MODE2, value: mode2);
337 if (ret < 0)
338 return ret;
339
340 device_for_each_child_node_scoped(dev, child) {
341 struct led_init_data init_data = {};
342 char default_label[32];
343
344 ret = fwnode_property_read_u32(fwnode: child, propname: "reg", val: &reg);
345 if (ret || reg >= chipdef->n_leds) {
346 dev_err(dev, "Invalid 'reg' property for node %pfw\n",
347 child);
348 return -EINVAL;
349 }
350
351 led->led_num = reg;
352 led->chip = chip;
353 led->led_cdev.brightness_set_blocking = pca963x_led_set;
354 if (hw_blink)
355 led->led_cdev.blink_set = pca963x_blink_set;
356 led->blinking = false;
357
358 init_data.fwnode = child;
359 /* for backwards compatibility */
360 init_data.devicename = "pca963x";
361 snprintf(buf: default_label, size: sizeof(default_label), fmt: "%d:%.2x:%u",
362 client->adapter->nr, client->addr, reg);
363 init_data.default_label = default_label;
364
365 ret = devm_led_classdev_register_ext(parent: dev, led_cdev: &led->led_cdev,
366 init_data: &init_data);
367 if (ret) {
368 dev_err(dev, "Failed to register LED for node %pfw\n",
369 child);
370 return ret;
371 }
372
373 ++led;
374 }
375
376 return 0;
377}
378
379static int pca963x_suspend(struct device *dev)
380{
381 struct pca963x *chip = dev_get_drvdata(dev);
382 u8 reg;
383
384 reg = i2c_smbus_read_byte_data(client: chip->client, PCA963X_MODE1);
385 reg = reg | BIT(PCA963X_MODE1_SLEEP);
386 i2c_smbus_write_byte_data(client: chip->client, PCA963X_MODE1, value: reg);
387
388 return 0;
389}
390
391static int pca963x_resume(struct device *dev)
392{
393 struct pca963x *chip = dev_get_drvdata(dev);
394 u8 reg;
395
396 reg = i2c_smbus_read_byte_data(client: chip->client, PCA963X_MODE1);
397 reg = reg & ~BIT(PCA963X_MODE1_SLEEP);
398 i2c_smbus_write_byte_data(client: chip->client, PCA963X_MODE1, value: reg);
399
400 return 0;
401}
402
403static DEFINE_SIMPLE_DEV_PM_OPS(pca963x_pm, pca963x_suspend, pca963x_resume);
404
405static const struct of_device_id of_pca963x_match[] = {
406 { .compatible = "nxp,pca9632", },
407 { .compatible = "nxp,pca9633", },
408 { .compatible = "nxp,pca9634", },
409 { .compatible = "nxp,pca9635", },
410 {},
411};
412MODULE_DEVICE_TABLE(of, of_pca963x_match);
413
414static int pca963x_probe(struct i2c_client *client)
415{
416 const struct i2c_device_id *id = i2c_client_get_device_id(client);
417 struct device *dev = &client->dev;
418 struct pca963x_chipdef *chipdef;
419 struct pca963x *chip;
420 int i, count;
421
422 chipdef = &pca963x_chipdefs[id->driver_data];
423
424 count = device_get_child_node_count(dev);
425 if (!count || count > chipdef->n_leds) {
426 dev_err(dev, "Node %pfw must define between 1 and %d LEDs\n",
427 dev_fwnode(dev), chipdef->n_leds);
428 return -EINVAL;
429 }
430
431 chip = devm_kzalloc(dev, struct_size(chip, leds, count), GFP_KERNEL);
432 if (!chip)
433 return -ENOMEM;
434
435 i2c_set_clientdata(client, data: chip);
436
437 mutex_init(&chip->mutex);
438 chip->chipdef = chipdef;
439 chip->client = client;
440
441 /* Turn off LEDs by default*/
442 for (i = 0; i < chipdef->n_leds / 4; i++)
443 i2c_smbus_write_byte_data(client, command: chipdef->ledout_base + i, value: 0x00);
444
445 /* Disable LED all-call address, and power down initially */
446 i2c_smbus_write_byte_data(client, PCA963X_MODE1, BIT(4));
447
448 return pca963x_register_leds(client, chip);
449}
450
451static struct i2c_driver pca963x_driver = {
452 .driver = {
453 .name = "leds-pca963x",
454 .of_match_table = of_pca963x_match,
455 .pm = pm_sleep_ptr(&pca963x_pm)
456 },
457 .probe = pca963x_probe,
458 .id_table = pca963x_id,
459};
460
461module_i2c_driver(pca963x_driver);
462
463MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>");
464MODULE_DESCRIPTION("PCA963X LED driver");
465MODULE_LICENSE("GPL v2");
466

source code of linux/drivers/leds/leds-pca963x.c