1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright 2015-16 Golden Delicious Computers
5 * Author: Nikolaus Schaller <hns@goldelico.com>
7 * LED driver for the IS31FL319{0,1,3,6,9} to drive 1, 3, 6 or 9 light
11 #include <linux/err.h>
12 #include <linux/i2c.h>
13 #include <linux/leds.h>
14 #include <linux/mod_devicetable.h>
15 #include <linux/module.h>
16 #include <linux/property.h>
17 #include <linux/regmap.h>
18 #include <linux/slab.h>
19 #include <linux/delay.h>
20 #include <linux/gpio/consumer.h>
22 /* register numbers */
23 #define IS31FL319X_SHUTDOWN 0x00
25 /* registers for 3190, 3191 and 3193 */
26 #define IS31FL3190_BREATHING 0x01
27 #define IS31FL3190_LEDMODE 0x02
28 #define IS31FL3190_CURRENT 0x03
29 #define IS31FL3190_PWM(channel) (0x04 + channel)
30 #define IS31FL3190_DATA_UPDATE 0x07
31 #define IS31FL3190_T0(channel) (0x0a + channel)
32 #define IS31FL3190_T1T2(channel) (0x10 + channel)
33 #define IS31FL3190_T3T4(channel) (0x16 + channel)
34 #define IS31FL3190_TIME_UPDATE 0x1c
35 #define IS31FL3190_LEDCONTROL 0x1d
36 #define IS31FL3190_RESET 0x2f
38 #define IS31FL3190_CURRENT_uA_MIN 5000
39 #define IS31FL3190_CURRENT_uA_DEFAULT 42000
40 #define IS31FL3190_CURRENT_uA_MAX 42000
41 #define IS31FL3190_CURRENT_MASK GENMASK(4, 2)
42 #define IS31FL3190_CURRENT_5_mA 0x02
43 #define IS31FL3190_CURRENT_10_mA 0x01
44 #define IS31FL3190_CURRENT_17dot5_mA 0x04
45 #define IS31FL3190_CURRENT_30_mA 0x03
46 #define IS31FL3190_CURRENT_42_mA 0x00
48 /* registers for 3196 and 3199 */
49 #define IS31FL3196_CTRL1 0x01
50 #define IS31FL3196_CTRL2 0x02
51 #define IS31FL3196_CONFIG1 0x03
52 #define IS31FL3196_CONFIG2 0x04
53 #define IS31FL3196_RAMP_MODE 0x05
54 #define IS31FL3196_BREATH_MARK 0x06
55 #define IS31FL3196_PWM(channel) (0x07 + channel)
56 #define IS31FL3196_DATA_UPDATE 0x10
57 #define IS31FL3196_T0(channel) (0x11 + channel)
58 #define IS31FL3196_T123_1 0x1a
59 #define IS31FL3196_T123_2 0x1b
60 #define IS31FL3196_T123_3 0x1c
61 #define IS31FL3196_T4(channel) (0x1d + channel)
62 #define IS31FL3196_TIME_UPDATE 0x26
63 #define IS31FL3196_RESET 0xff
65 #define IS31FL3196_REG_CNT (IS31FL3196_RESET + 1)
67 #define IS31FL319X_MAX_LEDS 9
69 /* CS (Current Setting) in CONFIG2 register */
70 #define IS31FL3196_CONFIG2_CS_SHIFT 4
71 #define IS31FL3196_CONFIG2_CS_MASK GENMASK(2, 0)
72 #define IS31FL3196_CONFIG2_CS_STEP_REF 12
74 #define IS31FL3196_CURRENT_uA_MIN 5000
75 #define IS31FL3196_CURRENT_uA_MAX 40000
76 #define IS31FL3196_CURRENT_uA_STEP 5000
77 #define IS31FL3196_CURRENT_uA_DEFAULT 20000
79 /* Audio gain in CONFIG2 register */
80 #define IS31FL3196_AUDIO_GAIN_DB_MAX ((u32)21)
81 #define IS31FL3196_AUDIO_GAIN_DB_STEP 3
84 * regmap is used as a cache of chip's register space,
85 * to avoid reading back brightness values from chip,
86 * which is known to hang.
88 struct is31fl319x_chip {
89 const struct is31fl319x_chipdef *cdef;
90 struct i2c_client *client;
91 struct gpio_desc *shutdown_gpio;
92 struct regmap *regmap;
96 struct is31fl319x_led {
97 struct is31fl319x_chip *chip;
98 struct led_classdev cdev;
101 } leds[IS31FL319X_MAX_LEDS];
104 struct is31fl319x_chipdef {
107 const struct regmap_config *is31fl319x_regmap_config;
108 int (*brightness_set)(struct led_classdev *cdev, enum led_brightness brightness);
115 static bool is31fl319x_readable_reg(struct device *dev, unsigned int reg)
117 /* we have no readable registers */
121 static bool is31fl3190_volatile_reg(struct device *dev, unsigned int reg)
123 /* volatile registers are not cached */
125 case IS31FL3190_DATA_UPDATE:
126 case IS31FL3190_TIME_UPDATE:
127 case IS31FL3190_RESET:
128 return true; /* always write-through */
134 static const struct reg_default is31fl3190_reg_defaults[] = {
135 { IS31FL3190_LEDMODE, 0x00 },
136 { IS31FL3190_CURRENT, 0x00 },
137 { IS31FL3190_PWM(0), 0x00 },
138 { IS31FL3190_PWM(1), 0x00 },
139 { IS31FL3190_PWM(2), 0x00 },
142 static struct regmap_config is31fl3190_regmap_config = {
145 .max_register = IS31FL3190_RESET,
146 .cache_type = REGCACHE_FLAT,
147 .readable_reg = is31fl319x_readable_reg,
148 .volatile_reg = is31fl3190_volatile_reg,
149 .reg_defaults = is31fl3190_reg_defaults,
150 .num_reg_defaults = ARRAY_SIZE(is31fl3190_reg_defaults),
153 static bool is31fl3196_volatile_reg(struct device *dev, unsigned int reg)
155 /* volatile registers are not cached */
157 case IS31FL3196_DATA_UPDATE:
158 case IS31FL3196_TIME_UPDATE:
159 case IS31FL3196_RESET:
160 return true; /* always write-through */
166 static const struct reg_default is31fl3196_reg_defaults[] = {
167 { IS31FL3196_CONFIG1, 0x00 },
168 { IS31FL3196_CONFIG2, 0x00 },
169 { IS31FL3196_PWM(0), 0x00 },
170 { IS31FL3196_PWM(1), 0x00 },
171 { IS31FL3196_PWM(2), 0x00 },
172 { IS31FL3196_PWM(3), 0x00 },
173 { IS31FL3196_PWM(4), 0x00 },
174 { IS31FL3196_PWM(5), 0x00 },
175 { IS31FL3196_PWM(6), 0x00 },
176 { IS31FL3196_PWM(7), 0x00 },
177 { IS31FL3196_PWM(8), 0x00 },
180 static struct regmap_config is31fl3196_regmap_config = {
183 .max_register = IS31FL3196_REG_CNT,
184 .cache_type = REGCACHE_FLAT,
185 .readable_reg = is31fl319x_readable_reg,
186 .volatile_reg = is31fl3196_volatile_reg,
187 .reg_defaults = is31fl3196_reg_defaults,
188 .num_reg_defaults = ARRAY_SIZE(is31fl3196_reg_defaults),
191 static int is31fl3190_brightness_set(struct led_classdev *cdev,
192 enum led_brightness brightness)
194 struct is31fl319x_led *led = container_of(cdev, struct is31fl319x_led, cdev);
195 struct is31fl319x_chip *is31 = led->chip;
196 int chan = led - is31->leds;
201 dev_dbg(&is31->client->dev, "channel %d: %d\n", chan, brightness);
203 mutex_lock(&is31->lock);
205 /* update PWM register */
206 ret = regmap_write(is31->regmap, IS31FL3190_PWM(chan), brightness);
210 /* read current brightness of all PWM channels */
211 for (i = 0; i < is31->cdef->num_leds; i++) {
212 unsigned int pwm_value;
216 * since neither cdev nor the chip can provide
217 * the current setting, we read from the regmap cache
220 ret = regmap_read(is31->regmap, IS31FL3190_PWM(i), &pwm_value);
221 on = ret >= 0 && pwm_value > LED_OFF;
227 dev_dbg(&is31->client->dev, "power up %02x\n", ctrl);
228 regmap_write(is31->regmap, IS31FL3190_LEDCONTROL, ctrl);
230 regmap_write(is31->regmap, IS31FL3190_DATA_UPDATE, 0x00);
231 /* enable chip from shut down and enable all channels */
232 ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x20);
234 dev_dbg(&is31->client->dev, "power down\n");
235 /* shut down (no need to clear LEDCONTROL) */
236 ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x01);
240 mutex_unlock(&is31->lock);
245 static int is31fl3196_brightness_set(struct led_classdev *cdev,
246 enum led_brightness brightness)
248 struct is31fl319x_led *led = container_of(cdev, struct is31fl319x_led, cdev);
249 struct is31fl319x_chip *is31 = led->chip;
250 int chan = led - is31->leds;
253 u8 ctrl1 = 0, ctrl2 = 0;
255 dev_dbg(&is31->client->dev, "channel %d: %d\n", chan, brightness);
257 mutex_lock(&is31->lock);
259 /* update PWM register */
260 ret = regmap_write(is31->regmap, IS31FL3196_PWM(chan), brightness);
264 /* read current brightness of all PWM channels */
265 for (i = 0; i < is31->cdef->num_leds; i++) {
266 unsigned int pwm_value;
270 * since neither cdev nor the chip can provide
271 * the current setting, we read from the regmap cache
274 ret = regmap_read(is31->regmap, IS31FL3196_PWM(i), &pwm_value);
275 on = ret >= 0 && pwm_value > LED_OFF;
278 ctrl1 |= on << i; /* 0..2 => bit 0..2 */
280 ctrl1 |= on << (i + 1); /* 3..5 => bit 4..6 */
282 ctrl2 |= on << (i - 6); /* 6..8 => bit 0..2 */
285 if (ctrl1 > 0 || ctrl2 > 0) {
286 dev_dbg(&is31->client->dev, "power up %02x %02x\n",
288 regmap_write(is31->regmap, IS31FL3196_CTRL1, ctrl1);
289 regmap_write(is31->regmap, IS31FL3196_CTRL2, ctrl2);
291 regmap_write(is31->regmap, IS31FL3196_DATA_UPDATE, 0x00);
292 /* enable chip from shut down */
293 ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x01);
295 dev_dbg(&is31->client->dev, "power down\n");
296 /* shut down (no need to clear CTRL1/2) */
297 ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x00);
301 mutex_unlock(&is31->lock);
306 static const struct is31fl319x_chipdef is31fl3190_cdef = {
308 .reset_reg = IS31FL3190_RESET,
309 .is31fl319x_regmap_config = &is31fl3190_regmap_config,
310 .brightness_set = is31fl3190_brightness_set,
311 .current_default = IS31FL3190_CURRENT_uA_DEFAULT,
312 .current_min = IS31FL3190_CURRENT_uA_MIN,
313 .current_max = IS31FL3190_CURRENT_uA_MAX,
314 .is_3196or3199 = false,
317 static const struct is31fl319x_chipdef is31fl3193_cdef = {
319 .reset_reg = IS31FL3190_RESET,
320 .is31fl319x_regmap_config = &is31fl3190_regmap_config,
321 .brightness_set = is31fl3190_brightness_set,
322 .current_default = IS31FL3190_CURRENT_uA_DEFAULT,
323 .current_min = IS31FL3190_CURRENT_uA_MIN,
324 .current_max = IS31FL3190_CURRENT_uA_MAX,
325 .is_3196or3199 = false,
328 static const struct is31fl319x_chipdef is31fl3196_cdef = {
330 .reset_reg = IS31FL3196_RESET,
331 .is31fl319x_regmap_config = &is31fl3196_regmap_config,
332 .brightness_set = is31fl3196_brightness_set,
333 .current_default = IS31FL3196_CURRENT_uA_DEFAULT,
334 .current_min = IS31FL3196_CURRENT_uA_MIN,
335 .current_max = IS31FL3196_CURRENT_uA_MAX,
336 .is_3196or3199 = true,
339 static const struct is31fl319x_chipdef is31fl3199_cdef = {
341 .reset_reg = IS31FL3196_RESET,
342 .is31fl319x_regmap_config = &is31fl3196_regmap_config,
343 .brightness_set = is31fl3196_brightness_set,
344 .current_default = IS31FL3196_CURRENT_uA_DEFAULT,
345 .current_min = IS31FL3196_CURRENT_uA_MIN,
346 .current_max = IS31FL3196_CURRENT_uA_MAX,
347 .is_3196or3199 = true,
350 static const struct of_device_id of_is31fl319x_match[] = {
351 { .compatible = "issi,is31fl3190", .data = &is31fl3190_cdef, },
352 { .compatible = "issi,is31fl3191", .data = &is31fl3190_cdef, },
353 { .compatible = "issi,is31fl3193", .data = &is31fl3193_cdef, },
354 { .compatible = "issi,is31fl3196", .data = &is31fl3196_cdef, },
355 { .compatible = "issi,is31fl3199", .data = &is31fl3199_cdef, },
356 { .compatible = "si-en,sn3190", .data = &is31fl3190_cdef, },
357 { .compatible = "si-en,sn3191", .data = &is31fl3190_cdef, },
358 { .compatible = "si-en,sn3193", .data = &is31fl3193_cdef, },
359 { .compatible = "si-en,sn3196", .data = &is31fl3196_cdef, },
360 { .compatible = "si-en,sn3199", .data = &is31fl3199_cdef, },
363 MODULE_DEVICE_TABLE(of, of_is31fl319x_match);
365 static int is31fl319x_parse_child_fw(const struct device *dev,
366 const struct fwnode_handle *child,
367 struct is31fl319x_led *led,
368 struct is31fl319x_chip *is31)
370 struct led_classdev *cdev = &led->cdev;
373 if (fwnode_property_read_string(child, "label", &cdev->name))
374 cdev->name = fwnode_get_name(child);
376 ret = fwnode_property_read_string(child, "linux,default-trigger", &cdev->default_trigger);
377 if (ret < 0 && ret != -EINVAL) /* is optional */
380 led->max_microamp = is31->cdef->current_default;
381 ret = fwnode_property_read_u32(child, "led-max-microamp", &led->max_microamp);
383 if (led->max_microamp < is31->cdef->current_min)
384 return -EINVAL; /* not supported */
385 led->max_microamp = min(led->max_microamp,
386 is31->cdef->current_max);
392 static int is31fl319x_parse_fw(struct device *dev, struct is31fl319x_chip *is31)
394 struct fwnode_handle *fwnode = dev_fwnode(dev), *child;
398 is31->shutdown_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
399 if (IS_ERR(is31->shutdown_gpio))
400 return dev_err_probe(dev, PTR_ERR(is31->shutdown_gpio),
401 "Failed to get shutdown gpio\n");
403 is31->cdef = device_get_match_data(dev);
406 fwnode_for_each_available_child_node(fwnode, child)
409 dev_dbg(dev, "probing with %d leds defined in DT\n", count);
411 if (!count || count > is31->cdef->num_leds)
412 return dev_err_probe(dev, -ENODEV,
413 "Number of leds defined must be between 1 and %u\n",
414 is31->cdef->num_leds);
416 fwnode_for_each_available_child_node(fwnode, child) {
417 struct is31fl319x_led *led;
420 ret = fwnode_property_read_u32(child, "reg", ®);
422 ret = dev_err_probe(dev, ret, "Failed to read led 'reg' property\n");
426 if (reg < 1 || reg > is31->cdef->num_leds) {
427 ret = dev_err_probe(dev, -EINVAL, "invalid led reg %u\n", reg);
431 led = &is31->leds[reg - 1];
433 if (led->configured) {
434 ret = dev_err_probe(dev, -EINVAL, "led %u is already configured\n", reg);
438 ret = is31fl319x_parse_child_fw(dev, child, led, is31);
440 ret = dev_err_probe(dev, ret, "led %u DT parsing failed\n", reg);
444 led->configured = true;
447 is31->audio_gain_db = 0;
448 if (is31->cdef->is_3196or3199) {
449 ret = fwnode_property_read_u32(fwnode, "audio-gain-db", &is31->audio_gain_db);
451 is31->audio_gain_db = min(is31->audio_gain_db,
452 IS31FL3196_AUDIO_GAIN_DB_MAX);
458 fwnode_handle_put(child);
462 static inline int is31fl3190_microamp_to_cs(struct device *dev, u32 microamp)
466 return IS31FL3190_CURRENT_5_mA;
468 return IS31FL3190_CURRENT_10_mA;
470 return IS31FL3190_CURRENT_17dot5_mA;
472 return IS31FL3190_CURRENT_30_mA;
474 return IS31FL3190_CURRENT_42_mA;
476 dev_warn(dev, "Unsupported current value: %d, using 5000 µA!\n", microamp);
477 return IS31FL3190_CURRENT_5_mA;
481 static inline int is31fl3196_microamp_to_cs(struct device *dev, u32 microamp)
483 /* round down to nearest supported value (range check done by caller) */
484 u32 step = microamp / IS31FL3196_CURRENT_uA_STEP;
486 return ((IS31FL3196_CONFIG2_CS_STEP_REF - step) &
487 IS31FL3196_CONFIG2_CS_MASK) <<
488 IS31FL3196_CONFIG2_CS_SHIFT; /* CS encoding */
491 static inline int is31fl3196_db_to_gain(u32 dezibel)
493 /* round down to nearest supported value (range check done by caller) */
494 return dezibel / IS31FL3196_AUDIO_GAIN_DB_STEP;
497 static int is31fl319x_probe(struct i2c_client *client)
499 struct is31fl319x_chip *is31;
500 struct device *dev = &client->dev;
503 u32 aggregated_led_microamp;
505 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
508 is31 = devm_kzalloc(&client->dev, sizeof(*is31), GFP_KERNEL);
512 mutex_init(&is31->lock);
513 err = devm_add_action(dev, (void (*)(void *))mutex_destroy, &is31->lock);
517 err = is31fl319x_parse_fw(&client->dev, is31);
521 if (is31->shutdown_gpio) {
522 gpiod_direction_output(is31->shutdown_gpio, 0);
524 gpiod_direction_output(is31->shutdown_gpio, 1);
527 is31->client = client;
528 is31->regmap = devm_regmap_init_i2c(client, is31->cdef->is31fl319x_regmap_config);
529 if (IS_ERR(is31->regmap))
530 return dev_err_probe(dev, PTR_ERR(is31->regmap), "failed to allocate register map\n");
532 i2c_set_clientdata(client, is31);
534 /* check for write-reply from chip (we can't read any registers) */
535 err = regmap_write(is31->regmap, is31->cdef->reset_reg, 0x00);
537 return dev_err_probe(dev, err, "no response from chip write\n");
540 * Kernel conventions require per-LED led-max-microamp property.
541 * But the chip does not allow to limit individual LEDs.
542 * So we take minimum from all subnodes for safety of hardware.
544 aggregated_led_microamp = is31->cdef->current_max;
545 for (i = 0; i < is31->cdef->num_leds; i++)
546 if (is31->leds[i].configured &&
547 is31->leds[i].max_microamp < aggregated_led_microamp)
548 aggregated_led_microamp = is31->leds[i].max_microamp;
550 if (is31->cdef->is_3196or3199)
551 regmap_write(is31->regmap, IS31FL3196_CONFIG2,
552 is31fl3196_microamp_to_cs(dev, aggregated_led_microamp) |
553 is31fl3196_db_to_gain(is31->audio_gain_db));
555 regmap_update_bits(is31->regmap, IS31FL3190_CURRENT, IS31FL3190_CURRENT_MASK,
556 is31fl3190_microamp_to_cs(dev, aggregated_led_microamp));
558 for (i = 0; i < is31->cdef->num_leds; i++) {
559 struct is31fl319x_led *led = &is31->leds[i];
561 if (!led->configured)
565 led->cdev.brightness_set_blocking = is31->cdef->brightness_set;
567 err = devm_led_classdev_register(&client->dev, &led->cdev);
576 * i2c-core (and modalias) requires that id_table be properly filled,
577 * even though it is not used for DeviceTree based instantiation.
579 static const struct i2c_device_id is31fl319x_id[] = {
592 MODULE_DEVICE_TABLE(i2c, is31fl319x_id);
594 static struct i2c_driver is31fl319x_driver = {
596 .name = "leds-is31fl319x",
597 .of_match_table = of_is31fl319x_match,
599 .probe_new = is31fl319x_probe,
600 .id_table = is31fl319x_id,
603 module_i2c_driver(is31fl319x_driver);
605 MODULE_AUTHOR("H. Nikolaus Schaller <hns@goldelico.com>");
606 MODULE_AUTHOR("Andrey Utkin <andrey_utkin@fastmail.com>");
607 MODULE_DESCRIPTION("IS31FL319X LED driver");
608 MODULE_LICENSE("GPL v2");