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_SHIFT 2
42 #define IS31FL3190_CURRENT_MASK GENMASK(4, 2)
43 #define IS31FL3190_CURRENT_5_mA 0x02
44 #define IS31FL3190_CURRENT_10_mA 0x01
45 #define IS31FL3190_CURRENT_17dot5_mA 0x04
46 #define IS31FL3190_CURRENT_30_mA 0x03
47 #define IS31FL3190_CURRENT_42_mA 0x00
49 /* registers for 3196 and 3199 */
50 #define IS31FL3196_CTRL1 0x01
51 #define IS31FL3196_CTRL2 0x02
52 #define IS31FL3196_CONFIG1 0x03
53 #define IS31FL3196_CONFIG2 0x04
54 #define IS31FL3196_RAMP_MODE 0x05
55 #define IS31FL3196_BREATH_MARK 0x06
56 #define IS31FL3196_PWM(channel) (0x07 + channel)
57 #define IS31FL3196_DATA_UPDATE 0x10
58 #define IS31FL3196_T0(channel) (0x11 + channel)
59 #define IS31FL3196_T123_1 0x1a
60 #define IS31FL3196_T123_2 0x1b
61 #define IS31FL3196_T123_3 0x1c
62 #define IS31FL3196_T4(channel) (0x1d + channel)
63 #define IS31FL3196_TIME_UPDATE 0x26
64 #define IS31FL3196_RESET 0xff
66 #define IS31FL3196_REG_CNT (IS31FL3196_RESET + 1)
68 #define IS31FL319X_MAX_LEDS 9
70 /* CS (Current Setting) in CONFIG2 register */
71 #define IS31FL3196_CONFIG2_CS_SHIFT 4
72 #define IS31FL3196_CONFIG2_CS_MASK GENMASK(2, 0)
73 #define IS31FL3196_CONFIG2_CS_STEP_REF 12
75 #define IS31FL3196_CURRENT_uA_MIN 5000
76 #define IS31FL3196_CURRENT_uA_MAX 40000
77 #define IS31FL3196_CURRENT_uA_STEP 5000
78 #define IS31FL3196_CURRENT_uA_DEFAULT 20000
80 /* Audio gain in CONFIG2 register */
81 #define IS31FL3196_AUDIO_GAIN_DB_MAX ((u32)21)
82 #define IS31FL3196_AUDIO_GAIN_DB_STEP 3
85 * regmap is used as a cache of chip's register space,
86 * to avoid reading back brightness values from chip,
87 * which is known to hang.
89 struct is31fl319x_chip {
90 const struct is31fl319x_chipdef *cdef;
91 struct i2c_client *client;
92 struct gpio_desc *shutdown_gpio;
93 struct regmap *regmap;
97 struct is31fl319x_led {
98 struct is31fl319x_chip *chip;
99 struct led_classdev cdev;
102 } leds[IS31FL319X_MAX_LEDS];
105 struct is31fl319x_chipdef {
108 const struct regmap_config *is31fl319x_regmap_config;
109 int (*brightness_set)(struct led_classdev *cdev, enum led_brightness brightness);
116 static bool is31fl319x_readable_reg(struct device *dev, unsigned int reg)
118 /* we have no readable registers */
122 static bool is31fl3190_volatile_reg(struct device *dev, unsigned int reg)
124 /* volatile registers are not cached */
126 case IS31FL3190_DATA_UPDATE:
127 case IS31FL3190_TIME_UPDATE:
128 case IS31FL3190_RESET:
129 return true; /* always write-through */
135 static const struct reg_default is31fl3190_reg_defaults[] = {
136 { IS31FL3190_LEDMODE, 0x00 },
137 { IS31FL3190_CURRENT, 0x00 },
138 { IS31FL3190_PWM(0), 0x00 },
139 { IS31FL3190_PWM(1), 0x00 },
140 { IS31FL3190_PWM(2), 0x00 },
143 static struct regmap_config is31fl3190_regmap_config = {
146 .max_register = IS31FL3190_RESET,
147 .cache_type = REGCACHE_FLAT,
148 .readable_reg = is31fl319x_readable_reg,
149 .volatile_reg = is31fl3190_volatile_reg,
150 .reg_defaults = is31fl3190_reg_defaults,
151 .num_reg_defaults = ARRAY_SIZE(is31fl3190_reg_defaults),
154 static bool is31fl3196_volatile_reg(struct device *dev, unsigned int reg)
156 /* volatile registers are not cached */
158 case IS31FL3196_DATA_UPDATE:
159 case IS31FL3196_TIME_UPDATE:
160 case IS31FL3196_RESET:
161 return true; /* always write-through */
167 static const struct reg_default is31fl3196_reg_defaults[] = {
168 { IS31FL3196_CONFIG1, 0x00 },
169 { IS31FL3196_CONFIG2, 0x00 },
170 { IS31FL3196_PWM(0), 0x00 },
171 { IS31FL3196_PWM(1), 0x00 },
172 { IS31FL3196_PWM(2), 0x00 },
173 { IS31FL3196_PWM(3), 0x00 },
174 { IS31FL3196_PWM(4), 0x00 },
175 { IS31FL3196_PWM(5), 0x00 },
176 { IS31FL3196_PWM(6), 0x00 },
177 { IS31FL3196_PWM(7), 0x00 },
178 { IS31FL3196_PWM(8), 0x00 },
181 static struct regmap_config is31fl3196_regmap_config = {
184 .max_register = IS31FL3196_REG_CNT,
185 .cache_type = REGCACHE_FLAT,
186 .readable_reg = is31fl319x_readable_reg,
187 .volatile_reg = is31fl3196_volatile_reg,
188 .reg_defaults = is31fl3196_reg_defaults,
189 .num_reg_defaults = ARRAY_SIZE(is31fl3196_reg_defaults),
192 static int is31fl3190_brightness_set(struct led_classdev *cdev,
193 enum led_brightness brightness)
195 struct is31fl319x_led *led = container_of(cdev, struct is31fl319x_led, cdev);
196 struct is31fl319x_chip *is31 = led->chip;
197 int chan = led - is31->leds;
202 dev_dbg(&is31->client->dev, "channel %d: %d\n", chan, brightness);
204 mutex_lock(&is31->lock);
206 /* update PWM register */
207 ret = regmap_write(is31->regmap, IS31FL3190_PWM(chan), brightness);
211 /* read current brightness of all PWM channels */
212 for (i = 0; i < is31->cdef->num_leds; i++) {
213 unsigned int pwm_value;
217 * since neither cdev nor the chip can provide
218 * the current setting, we read from the regmap cache
221 ret = regmap_read(is31->regmap, IS31FL3190_PWM(i), &pwm_value);
222 on = ret >= 0 && pwm_value > LED_OFF;
228 dev_dbg(&is31->client->dev, "power up %02x\n", ctrl);
229 regmap_write(is31->regmap, IS31FL3190_LEDCONTROL, ctrl);
231 regmap_write(is31->regmap, IS31FL3190_DATA_UPDATE, 0x00);
232 /* enable chip from shut down and enable all channels */
233 ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x20);
235 dev_dbg(&is31->client->dev, "power down\n");
236 /* shut down (no need to clear LEDCONTROL) */
237 ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x01);
241 mutex_unlock(&is31->lock);
246 static int is31fl3196_brightness_set(struct led_classdev *cdev,
247 enum led_brightness brightness)
249 struct is31fl319x_led *led = container_of(cdev, struct is31fl319x_led, cdev);
250 struct is31fl319x_chip *is31 = led->chip;
251 int chan = led - is31->leds;
254 u8 ctrl1 = 0, ctrl2 = 0;
256 dev_dbg(&is31->client->dev, "channel %d: %d\n", chan, brightness);
258 mutex_lock(&is31->lock);
260 /* update PWM register */
261 ret = regmap_write(is31->regmap, IS31FL3196_PWM(chan), brightness);
265 /* read current brightness of all PWM channels */
266 for (i = 0; i < is31->cdef->num_leds; i++) {
267 unsigned int pwm_value;
271 * since neither cdev nor the chip can provide
272 * the current setting, we read from the regmap cache
275 ret = regmap_read(is31->regmap, IS31FL3196_PWM(i), &pwm_value);
276 on = ret >= 0 && pwm_value > LED_OFF;
279 ctrl1 |= on << i; /* 0..2 => bit 0..2 */
281 ctrl1 |= on << (i + 1); /* 3..5 => bit 4..6 */
283 ctrl2 |= on << (i - 6); /* 6..8 => bit 0..2 */
286 if (ctrl1 > 0 || ctrl2 > 0) {
287 dev_dbg(&is31->client->dev, "power up %02x %02x\n",
289 regmap_write(is31->regmap, IS31FL3196_CTRL1, ctrl1);
290 regmap_write(is31->regmap, IS31FL3196_CTRL2, ctrl2);
292 regmap_write(is31->regmap, IS31FL3196_DATA_UPDATE, 0x00);
293 /* enable chip from shut down */
294 ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x01);
296 dev_dbg(&is31->client->dev, "power down\n");
297 /* shut down (no need to clear CTRL1/2) */
298 ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x00);
302 mutex_unlock(&is31->lock);
307 static const struct is31fl319x_chipdef is31fl3190_cdef = {
309 .reset_reg = IS31FL3190_RESET,
310 .is31fl319x_regmap_config = &is31fl3190_regmap_config,
311 .brightness_set = is31fl3190_brightness_set,
312 .current_default = IS31FL3190_CURRENT_uA_DEFAULT,
313 .current_min = IS31FL3190_CURRENT_uA_MIN,
314 .current_max = IS31FL3190_CURRENT_uA_MAX,
315 .is_3196or3199 = false,
318 static const struct is31fl319x_chipdef is31fl3193_cdef = {
320 .reset_reg = IS31FL3190_RESET,
321 .is31fl319x_regmap_config = &is31fl3190_regmap_config,
322 .brightness_set = is31fl3190_brightness_set,
323 .current_default = IS31FL3190_CURRENT_uA_DEFAULT,
324 .current_min = IS31FL3190_CURRENT_uA_MIN,
325 .current_max = IS31FL3190_CURRENT_uA_MAX,
326 .is_3196or3199 = false,
329 static const struct is31fl319x_chipdef is31fl3196_cdef = {
331 .reset_reg = IS31FL3196_RESET,
332 .is31fl319x_regmap_config = &is31fl3196_regmap_config,
333 .brightness_set = is31fl3196_brightness_set,
334 .current_default = IS31FL3196_CURRENT_uA_DEFAULT,
335 .current_min = IS31FL3196_CURRENT_uA_MIN,
336 .current_max = IS31FL3196_CURRENT_uA_MAX,
337 .is_3196or3199 = true,
340 static const struct is31fl319x_chipdef is31fl3199_cdef = {
342 .reset_reg = IS31FL3196_RESET,
343 .is31fl319x_regmap_config = &is31fl3196_regmap_config,
344 .brightness_set = is31fl3196_brightness_set,
345 .current_default = IS31FL3196_CURRENT_uA_DEFAULT,
346 .current_min = IS31FL3196_CURRENT_uA_MIN,
347 .current_max = IS31FL3196_CURRENT_uA_MAX,
348 .is_3196or3199 = true,
351 static const struct of_device_id of_is31fl319x_match[] = {
352 { .compatible = "issi,is31fl3190", .data = &is31fl3190_cdef, },
353 { .compatible = "issi,is31fl3191", .data = &is31fl3190_cdef, },
354 { .compatible = "issi,is31fl3193", .data = &is31fl3193_cdef, },
355 { .compatible = "issi,is31fl3196", .data = &is31fl3196_cdef, },
356 { .compatible = "issi,is31fl3199", .data = &is31fl3199_cdef, },
357 { .compatible = "si-en,sn3190", .data = &is31fl3190_cdef, },
358 { .compatible = "si-en,sn3191", .data = &is31fl3190_cdef, },
359 { .compatible = "si-en,sn3193", .data = &is31fl3193_cdef, },
360 { .compatible = "si-en,sn3196", .data = &is31fl3196_cdef, },
361 { .compatible = "si-en,sn3199", .data = &is31fl3199_cdef, },
364 MODULE_DEVICE_TABLE(of, of_is31fl319x_match);
366 static int is31fl319x_parse_child_fw(const struct device *dev,
367 const struct fwnode_handle *child,
368 struct is31fl319x_led *led,
369 struct is31fl319x_chip *is31)
371 struct led_classdev *cdev = &led->cdev;
374 if (fwnode_property_read_string(child, "label", &cdev->name))
375 cdev->name = fwnode_get_name(child);
377 ret = fwnode_property_read_string(child, "linux,default-trigger", &cdev->default_trigger);
378 if (ret < 0 && ret != -EINVAL) /* is optional */
381 led->max_microamp = is31->cdef->current_default;
382 ret = fwnode_property_read_u32(child, "led-max-microamp", &led->max_microamp);
384 if (led->max_microamp < is31->cdef->current_min)
385 return -EINVAL; /* not supported */
386 led->max_microamp = min(led->max_microamp,
387 is31->cdef->current_max);
393 static int is31fl319x_parse_fw(struct device *dev, struct is31fl319x_chip *is31)
395 struct fwnode_handle *fwnode = dev_fwnode(dev), *child;
399 is31->shutdown_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
400 if (IS_ERR(is31->shutdown_gpio))
401 return dev_err_probe(dev, PTR_ERR(is31->shutdown_gpio),
402 "Failed to get shutdown gpio\n");
404 is31->cdef = device_get_match_data(dev);
407 fwnode_for_each_available_child_node(fwnode, child)
410 dev_dbg(dev, "probing with %d leds defined in DT\n", count);
412 if (!count || count > is31->cdef->num_leds)
413 return dev_err_probe(dev, -ENODEV,
414 "Number of leds defined must be between 1 and %u\n",
415 is31->cdef->num_leds);
417 fwnode_for_each_available_child_node(fwnode, child) {
418 struct is31fl319x_led *led;
421 ret = fwnode_property_read_u32(child, "reg", ®);
423 ret = dev_err_probe(dev, ret, "Failed to read led 'reg' property\n");
427 if (reg < 1 || reg > is31->cdef->num_leds) {
428 ret = dev_err_probe(dev, -EINVAL, "invalid led reg %u\n", reg);
432 led = &is31->leds[reg - 1];
434 if (led->configured) {
435 ret = dev_err_probe(dev, -EINVAL, "led %u is already configured\n", reg);
439 ret = is31fl319x_parse_child_fw(dev, child, led, is31);
441 ret = dev_err_probe(dev, ret, "led %u DT parsing failed\n", reg);
445 led->configured = true;
448 is31->audio_gain_db = 0;
449 if (is31->cdef->is_3196or3199) {
450 ret = fwnode_property_read_u32(fwnode, "audio-gain-db", &is31->audio_gain_db);
452 is31->audio_gain_db = min(is31->audio_gain_db,
453 IS31FL3196_AUDIO_GAIN_DB_MAX);
459 fwnode_handle_put(child);
463 static inline int is31fl3190_microamp_to_cs(struct device *dev, u32 microamp)
467 return IS31FL3190_CURRENT_5_mA;
469 return IS31FL3190_CURRENT_10_mA;
471 return IS31FL3190_CURRENT_17dot5_mA;
473 return IS31FL3190_CURRENT_30_mA;
475 return IS31FL3190_CURRENT_42_mA;
477 dev_warn(dev, "Unsupported current value: %d, using 5000 µA!\n", microamp);
478 return IS31FL3190_CURRENT_5_mA;
482 static inline int is31fl3196_microamp_to_cs(struct device *dev, u32 microamp)
484 /* round down to nearest supported value (range check done by caller) */
485 u32 step = microamp / IS31FL3196_CURRENT_uA_STEP;
487 return ((IS31FL3196_CONFIG2_CS_STEP_REF - step) &
488 IS31FL3196_CONFIG2_CS_MASK) <<
489 IS31FL3196_CONFIG2_CS_SHIFT; /* CS encoding */
492 static inline int is31fl3196_db_to_gain(u32 dezibel)
494 /* round down to nearest supported value (range check done by caller) */
495 return dezibel / IS31FL3196_AUDIO_GAIN_DB_STEP;
498 static void is31f1319x_mutex_destroy(void *lock)
503 static int is31fl319x_probe(struct i2c_client *client)
505 struct is31fl319x_chip *is31;
506 struct device *dev = &client->dev;
509 u32 aggregated_led_microamp;
511 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
514 is31 = devm_kzalloc(&client->dev, sizeof(*is31), GFP_KERNEL);
518 mutex_init(&is31->lock);
519 err = devm_add_action_or_reset(dev, is31f1319x_mutex_destroy, &is31->lock);
523 err = is31fl319x_parse_fw(&client->dev, is31);
527 if (is31->shutdown_gpio) {
528 gpiod_direction_output(is31->shutdown_gpio, 0);
530 gpiod_direction_output(is31->shutdown_gpio, 1);
533 is31->client = client;
534 is31->regmap = devm_regmap_init_i2c(client, is31->cdef->is31fl319x_regmap_config);
535 if (IS_ERR(is31->regmap))
536 return dev_err_probe(dev, PTR_ERR(is31->regmap), "failed to allocate register map\n");
538 i2c_set_clientdata(client, is31);
540 /* check for write-reply from chip (we can't read any registers) */
541 err = regmap_write(is31->regmap, is31->cdef->reset_reg, 0x00);
543 return dev_err_probe(dev, err, "no response from chip write\n");
546 * Kernel conventions require per-LED led-max-microamp property.
547 * But the chip does not allow to limit individual LEDs.
548 * So we take minimum from all subnodes for safety of hardware.
550 aggregated_led_microamp = is31->cdef->current_max;
551 for (i = 0; i < is31->cdef->num_leds; i++)
552 if (is31->leds[i].configured &&
553 is31->leds[i].max_microamp < aggregated_led_microamp)
554 aggregated_led_microamp = is31->leds[i].max_microamp;
556 if (is31->cdef->is_3196or3199)
557 regmap_write(is31->regmap, IS31FL3196_CONFIG2,
558 is31fl3196_microamp_to_cs(dev, aggregated_led_microamp) |
559 is31fl3196_db_to_gain(is31->audio_gain_db));
561 regmap_update_bits(is31->regmap, IS31FL3190_CURRENT, IS31FL3190_CURRENT_MASK,
562 is31fl3190_microamp_to_cs(dev, aggregated_led_microamp) << IS31FL3190_CURRENT_SHIFT);
564 for (i = 0; i < is31->cdef->num_leds; i++) {
565 struct is31fl319x_led *led = &is31->leds[i];
567 if (!led->configured)
571 led->cdev.brightness_set_blocking = is31->cdef->brightness_set;
573 err = devm_led_classdev_register(&client->dev, &led->cdev);
582 * i2c-core (and modalias) requires that id_table be properly filled,
583 * even though it is not used for DeviceTree based instantiation.
585 static const struct i2c_device_id is31fl319x_id[] = {
598 MODULE_DEVICE_TABLE(i2c, is31fl319x_id);
600 static struct i2c_driver is31fl319x_driver = {
602 .name = "leds-is31fl319x",
603 .of_match_table = of_is31fl319x_match,
605 .probe = is31fl319x_probe,
606 .id_table = is31fl319x_id,
609 module_i2c_driver(is31fl319x_driver);
611 MODULE_AUTHOR("H. Nikolaus Schaller <hns@goldelico.com>");
612 MODULE_AUTHOR("Andrey Utkin <andrey_utkin@fastmail.com>");
613 MODULE_DESCRIPTION("IS31FL319X LED driver");
614 MODULE_LICENSE("GPL v2");