// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2015-16 Golden Delicious Computers
*
* Author: Nikolaus Schaller <hns@goldelico.com>
*
* LED driver for the IS31FL319{0,1,3,6,9} to drive 1, 3, 6 or 9 light
* effect LEDs.
*/
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
/* register numbers */
#define IS31FL319X_SHUTDOWN 0x00
/* registers for 3190, 3191 and 3193 */
#define IS31FL3190_BREATHING 0x01
#define IS31FL3190_LEDMODE 0x02
#define IS31FL3190_CURRENT 0x03
#define IS31FL3190_PWM(channel) (0x04 + channel)
#define IS31FL3190_DATA_UPDATE 0x07
#define IS31FL3190_T0(channel) (0x0a + channel)
#define IS31FL3190_T1T2(channel) (0x10 + channel)
#define IS31FL3190_T3T4(channel) (0x16 + channel)
#define IS31FL3190_TIME_UPDATE 0x1c
#define IS31FL3190_LEDCONTROL 0x1d
#define IS31FL3190_RESET 0x2f
#define IS31FL3190_CURRENT_uA_MIN 5000
#define IS31FL3190_CURRENT_uA_DEFAULT 42000
#define IS31FL3190_CURRENT_uA_MAX 42000
#define IS31FL3190_CURRENT_MASK GENMASK(4, 2)
#define IS31FL3190_CURRENT_5_mA 0x02
#define IS31FL3190_CURRENT_10_mA 0x01
#define IS31FL3190_CURRENT_17dot5_mA 0x04
#define IS31FL3190_CURRENT_30_mA 0x03
#define IS31FL3190_CURRENT_42_mA 0x00
/* registers for 3196 and 3199 */
#define IS31FL3196_CTRL1 0x01
#define IS31FL3196_CTRL2 0x02
#define IS31FL3196_CONFIG1 0x03
#define IS31FL3196_CONFIG2 0x04
#define IS31FL3196_RAMP_MODE 0x05
#define IS31FL3196_BREATH_MARK 0x06
#define IS31FL3196_PWM(channel) (0x07 + channel)
#define IS31FL3196_DATA_UPDATE 0x10
#define IS31FL3196_T0(channel) (0x11 + channel)
#define IS31FL3196_T123_1 0x1a
#define IS31FL3196_T123_2 0x1b
#define IS31FL3196_T123_3 0x1c
#define IS31FL3196_T4(channel) (0x1d + channel)
#define IS31FL3196_TIME_UPDATE 0x26
#define IS31FL3196_RESET 0xff
#define IS31FL3196_REG_CNT (IS31FL3196_RESET + 1)
#define IS31FL319X_MAX_LEDS 9
/* CS (Current Setting) in CONFIG2 register */
#define IS31FL3196_CONFIG2_CS_SHIFT 4
#define IS31FL3196_CONFIG2_CS_MASK GENMASK(2, 0)
#define IS31FL3196_CONFIG2_CS_STEP_REF 12
#define IS31FL3196_CURRENT_uA_MIN 5000
#define IS31FL3196_CURRENT_uA_MAX 40000
#define IS31FL3196_CURRENT_uA_STEP 5000
#define IS31FL3196_CURRENT_uA_DEFAULT 20000
/* Audio gain in CONFIG2 register */
#define IS31FL3196_AUDIO_GAIN_DB_MAX ((u32)21)
#define IS31FL3196_AUDIO_GAIN_DB_STEP 3
/*
* regmap is used as a cache of chip's register space,
* to avoid reading back brightness values from chip,
* which is known to hang.
*/
struct is31fl319x_chip {
const struct is31fl319x_chipdef *cdef;
struct i2c_client *client;
struct gpio_desc *shutdown_gpio;
struct regmap *regmap;
struct mutex lock;
u32 audio_gain_db;
struct is31fl319x_led {
struct is31fl319x_chip *chip;
struct led_classdev cdev;
u32 max_microamp;
bool configured;
} leds[IS31FL319X_MAX_LEDS];
};
struct is31fl319x_chipdef {
int num_leds;
u8 reset_reg;
const struct regmap_config *is31fl319x_regmap_config;
int (*brightness_set)(struct led_classdev *cdev, enum led_brightness brightness);
u32 current_default;
u32 current_min;
u32 current_max;
bool is_3196or3199;
};
static bool is31fl319x_readable_reg(struct device *dev, unsigned int reg)
{
/* we have no readable registers */
return false;
}
static bool is31fl3190_volatile_reg(struct device *dev, unsigned int reg)
{
/* volatile registers are not cached */
switch (reg) {
case IS31FL3190_DATA_UPDATE:
case IS31FL3190_TIME_UPDATE:
case IS31FL3190_RESET:
return true; /* always write-through */
default:
return false;
}
}
static const struct reg_default is31fl3190_reg_defaults[] = {
{ IS31FL3190_LEDMODE, 0x00 },
{ IS31FL3190_CURRENT, 0x00 },
{ IS31FL3190_PWM(0), 0x00 },
{ IS31FL3190_PWM(1), 0x00 },
{ IS31FL3190_PWM(2), 0x00 },
};
static struct regmap_config is31fl3190_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = IS31FL3190_RESET,
.cache_type = REGCACHE_FLAT,
.readable_reg = is31fl319x_readable_reg,
.volatile_reg = is31fl3190_volatile_reg,
.reg_defaults = is31fl3190_reg_defaults,
.num_reg_defaults = ARRAY_SIZE(is31fl3190_reg_defaults),
};
static bool is31fl3196_volatile_reg(struct device *dev, unsigned int reg)
{
/* volatile registers are not cached */
switch (reg) {
case IS31FL3196_DATA_UPDATE:
case IS31FL3196_TIME_UPDATE:
case IS31FL3196_RESET:
return true; /* always write-through */
default:
return false;
}
}
static const struct reg_default is31fl3196_reg_defaults[] = {
{ IS31FL3196_CONFIG1, 0x00 },
{ IS31FL3196_CONFIG2, 0x00 },
{ IS31FL3196_PWM(0), 0x00 },
{ IS31FL3196_PWM(1), 0x00 },
{ IS31FL3196_PWM(2), 0x00 },
{ IS31FL3196_PWM(3), 0x00 },
{ IS31FL3196_PWM(4), 0x00 },
{ IS31FL3196_PWM(5), 0x00 },
{ IS31FL3196_PWM(6), 0x00 },
{ IS31FL3196_PWM(7), 0x00 },
{ IS31FL3196_PWM(8), 0x00 },
};
static struct regmap_config is31fl3196_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = IS31FL3196_REG_CNT,
.cache_type = REGCACHE_FLAT,
.readable_reg = is31fl319x_readable_reg,
.volatile_reg = is31fl3196_volatile_reg,
.reg_defaults = is31fl3196_reg_defaults,
.num_reg_defaults = ARRAY_SIZE(is31fl3196_reg_defaults),
};
static int is31fl3190_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct is31fl319x_led *led = container_of(cdev, struct is31fl319x_led, cdev);
struct is31fl319x_chip *is31 = led->chip;
int chan = led - is31->leds;
int ret;
int i;
u8 ctrl = 0;
dev_dbg(&is31->client->dev, "channel %d: %d\n", chan, brightness);
mutex_lock(&is31->lock);
/* update PWM register */
ret = regmap_write(is31->regmap, IS31FL3190_PWM(chan), brightness);
if (ret < 0)
goto out;
/* read current brightness of all PWM channels */
for (i = 0; i < is31->cdef->num_leds; i++) {
unsigned int pwm_value;
bool on;
/*
* since neither cdev nor the chip can provide
* the current setting, we read from the regmap cache
*/
ret = regmap_read(is31->regmap, IS31FL3190_PWM(i), &pwm_value);
on = ret >= 0 && pwm_value > LED_OFF;
ctrl |= on << i;
}
if (ctrl > 0) {
dev_dbg(&is31->client->dev, "power up %02x\n", ctrl);
regmap_write(is31->regmap, IS31FL3190_LEDCONTROL, ctrl);
/* update PWMs */
regmap_write(is31->regmap, IS31FL3190_DATA_UPDATE, 0x00);
/* enable chip from shut down and enable all channels */
ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x20);
} else {
dev_dbg(&is31->client->dev, "power down\n");
/* shut down (no need to clear LEDCONTROL) */
ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x01);
}
out:
mutex_unlock(&is31->lock);
return ret;
}
static int is31fl3196_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct is31fl319x_led *led = container_of(cdev, struct is31fl319x_led, cdev);
struct is31fl319x_chip *is31 = led->chip;
int chan = led - is31->leds;
int ret;
int i;
u8 ctrl1 = 0, ctrl2 = 0;
dev_dbg(&is31->client->dev, "channel %d: %d\n", chan, brightness);
mutex_lock(&is31->lock);
/* update PWM register */
ret = regmap_write(is31->regmap, IS31FL3196_PWM(chan), brightness);
if (ret < 0)
goto out;
/* read current brightness of all PWM channels */
for (i = 0; i < is31->cdef->num_leds; i++) {
unsigned int pwm_value;
bool on;
/*
* since neither cdev nor the chip can provide
* the current setting, we read from the regmap cache
*/
ret = regmap_read(is31->regmap, IS31FL3196_PWM(i), &pwm_value);
on = ret >= 0 && pwm_value > LED_OFF;
if (i < 3)
ctrl1 |= on << i; /* 0..2 => bit 0..2 */
else if (i < 6)
ctrl1 |= on << (i + 1); /* 3..5 => bit 4..6 */
else
ctrl2 |= on << (i - 6); /* 6..8 => bit 0..2 */
}
if (ctrl1 > 0 || ctrl2 > 0) {
dev_dbg(&is31->client->dev, "power up %02x %02x\n",
ctrl1, ctrl2);
regmap_write(is31->regmap, IS31FL3196_CTRL1, ctrl1);
regmap_write(is31->regmap, IS31FL3196_CTRL2, ctrl2);
/* update PWMs */
regmap_write(is31->regmap, IS31FL3196_DATA_UPDATE, 0x00);
/* enable chip from shut down */
ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x01);
} else {
dev_dbg(&is31->client->dev, "power down\n");
/* shut down (no need to clear CTRL1/2) */
ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x00);
}
out:
mutex_unlock(&is31->lock);
return ret;
}
static const struct is31fl319x_chipdef is31fl3190_cdef = {
.num_leds = 1,
.reset_reg = IS31FL3190_RESET,
.is31fl319x_regmap_config = &is31fl3190_regmap_config,
.brightness_set = is31fl3190_brightness_set,
.current_default = IS31FL3190_CURRENT_uA_DEFAULT,
.current_min = IS31FL3190_CURRENT_uA_MIN,
.current_max = IS31FL3190_CURRENT_uA_MAX,
.is_3196or3199 = false,
};
static const struct is31fl319x_chipdef is31fl3193_cdef = {
.num_leds = 3,
.reset_reg = IS31FL3190_RESET,
.is31fl319x_regmap_config = &is31fl3190_regmap_config,
.brightness_set = is31fl3190_brightness_set,
.current_default = IS31FL3190_CURRENT_uA_DEFAULT,
.current_min = IS31FL3190_CURRENT_uA_MIN,
.current_max = IS31FL3190_CURRENT_uA_MAX,
.is_3196or3199 = false,
};
static const struct is31fl319x_chipdef is31fl3196_cdef = {
.num_leds = 6,
.reset_reg = IS31FL3196_RESET,
.is31fl319x_regmap_config = &is31fl3196_regmap_config,
.brightness_set = is31fl3196_brightness_set,
.current_default = IS31FL3196_CURRENT_uA_DEFAULT,
.current_min = IS31FL3196_CURRENT_uA_MIN,
.current_max = IS31FL3196_CURRENT_uA_MAX,
.is_3196or3199 = true,
};
static const struct is31fl319x_chipdef is31fl3199_cdef = {
.num_leds = 9,
.reset_reg = IS31FL3196_RESET,
.is31fl319x_regmap_config = &is31fl3196_regmap_config,
.brightness_set = is31fl3196_brightness_set,
.current_default = IS31FL3196_CURRENT_uA_DEFAULT,
.current_min = IS31FL3196_CURRENT_uA_MIN,
.current_max = IS31FL3196_CURRENT_uA_MAX,
.is_3196or3199 = true,
};
static const struct of_device_id of_is31fl319x_match[] = {
{ .compatible = "issi,is31fl3190", .data = &is31fl3190_cdef, },
{ .compatible = "issi,is31fl3191", .data = &is31fl3190_cdef, },
{ .compatible = "issi,is31fl3193", .data = &is31fl3193_cdef, },
{ .compatible = "issi,is31fl3196", .data = &is31fl3196_cdef, },
{ .compatible = "issi,is31fl3199", .data = &is31fl3199_cdef, },
{ .compatible = "si-en,sn3190", .data = &is31fl3190_cdef, },
{ .compatible = "si-en,sn3191", .data = &is31fl3190_cdef, },
{ .compatible = "si-en,sn3193", .data = &is31fl3193_cdef, },
{ .compatible = "si-en,sn3196", .data = &is31fl3196_cdef, },
{ .compatible = "si-en,sn3199", .data = &is31fl3199_cdef, },
{ }
};
MODULE_DEVICE_TABLE(of, of_is31fl319x_match);
static int is31fl319x_parse_child_fw(const struct device *dev,
const struct fwnode_handle *child,
struct is31fl319x_led *led,
struct is31fl319x_chip *is31)
{
struct led_classdev *cdev = &led->cdev;
int ret;
if (fwnode_property_read_string(child, "label", &cdev->name))
cdev->name = fwnode_get_name(child);
ret = fwnode_property_read_string(child, "linux,default-trigger", &cdev->default_trigger);
if (ret < 0 && ret != -EINVAL) /* is optional */
return ret;
led->max_microamp = is31->cdef->current_default;
ret = fwnode_property_read_u32(child, "led-max-microamp", &led->max_microamp);
if (!ret) {
if (led->max_microamp < is31->cdef->current_min)
return -EINVAL; /* not supported */
led->max_microamp = min(led->max_microamp,
is31->cdef->current_max);
}
return 0;
}
static int is31fl319x_parse_fw(struct device *dev, struct is31fl319x_chip *is31)
{
struct fwnode_handle *fwnode = dev_fwnode(dev), *child;
int count;
int ret;
is31->shutdown_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
if (IS_ERR(is31->shutdown_gpio))
return dev_err_probe(dev, PTR_ERR(is31->shutdown_gpio),
"Failed to get shutdown gpio\n");
is31->cdef = device_get_match_data(dev);
count = 0;
fwnode_for_each_available_child_node(fwnode, child)
count++;
dev_dbg(dev, "probing with %d leds defined in DT\n", count);
if (!count || count > is31->cdef->num_leds)
return dev_err_probe(dev, -ENODEV,
"Number of leds defined must be between 1 and %u\n",
is31->cdef->num_leds);
fwnode_for_each_available_child_node(fwnode, child) {
struct is31fl319x_led *led;
u32 reg;
ret = fwnode_property_read_u32(child, "reg", ®);
if (ret) {
ret = dev_err_probe(dev, ret, "Failed to read led 'reg' property\n");
goto put_child_node;
}
if (reg < 1 || reg > is31->cdef->num_leds) {
ret = dev_err_probe(dev, -EINVAL, "invalid led reg %u\n", reg);
goto put_child_node;
}
led = &is31->leds[reg - 1];
if (led->configured) {
ret = dev_err_probe(dev, -EINVAL, "led %u is already configured\n", reg);
goto put_child_node;
}
ret = is31fl319x_parse_child_fw(dev, child, led, is31);
if (ret) {
ret = dev_err_probe(dev, ret, "led %u DT parsing failed\n", reg);
goto put_child_node;
}
led->configured = true;
}
is31->audio_gain_db = 0;
if (is31->cdef->is_3196or3199) {
ret = fwnode_property_read_u32(fwnode, "audio-gain-db", &is31->audio_gain_db);
if (!ret)
is31->audio_gain_db = min(is31->audio_gain_db,
IS31FL3196_AUDIO_GAIN_DB_MAX);
}
return 0;
put_child_node:
fwnode_handle_put(child);
return ret;
}
static inline int is31fl3190_microamp_to_cs(struct device *dev, u32 microamp)
{
switch (microamp) {
case 5000:
return IS31FL3190_CURRENT_5_mA;
case 10000:
return IS31FL3190_CURRENT_10_mA;
case 17500:
return IS31FL3190_CURRENT_17dot5_mA;
case 30000:
return IS31FL3190_CURRENT_30_mA;
case 42000:
return IS31FL3190_CURRENT_42_mA;
default:
dev_warn(dev, "Unsupported current value: %d, using 5000 µA!\n", microamp);
return IS31FL3190_CURRENT_5_mA;
}
}
static inline int is31fl3196_microamp_to_cs(struct device *dev, u32 microamp)
{
/* round down to nearest supported value (range check done by caller) */
u32 step = microamp / IS31FL3196_CURRENT_uA_STEP;
return ((IS31FL3196_CONFIG2_CS_STEP_REF - step) &
IS31FL3196_CONFIG2_CS_MASK) <<
IS31FL3196_CONFIG2_CS_SHIFT; /* CS encoding */
}
static inline int is31fl3196_db_to_gain(u32 dezibel)
{
/* round down to nearest supported value (range check done by caller) */
return dezibel / IS31FL3196_AUDIO_GAIN_DB_STEP;
}
static int is31fl319x_probe(struct i2c_client *client)
{
struct is31fl319x_chip *is31;
struct device *dev = &client->dev;
int err;
int i = 0;
u32 aggregated_led_microamp;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
return -EIO;
is31 = devm_kzalloc(&client->dev, sizeof(*is31), GFP_KERNEL);
if (!is31)
return -ENOMEM;
mutex_init(&is31->lock);
err = devm_add_action(dev, (void (*)(void *))mutex_destroy, &is31->lock);
if (err)
return err;
err = is31fl319x_parse_fw(&client->dev, is31);
if (err)
return err;
if (is31->shutdown_gpio) {
gpiod_direction_output(is31->shutdown_gpio, 0);
mdelay(5);
gpiod_direction_output(is31->shutdown_gpio, 1);
}
is31->client = client;
is31->regmap = devm_regmap_init_i2c(client, is31->cdef->is31fl319x_regmap_config);
if (IS_ERR(is31->regmap))
return dev_err_probe(dev, PTR_ERR(is31->regmap), "failed to allocate register map\n");
i2c_set_clientdata(client, is31);
/* check for write-reply from chip (we can't read any registers) */
err = regmap_write(is31->regmap, is31->cdef->reset_reg, 0x00);
if (err < 0)
return dev_err_probe(dev, err, "no response from chip write\n");
/*
* Kernel conventions require per-LED led-max-microamp property.
* But the chip does not allow to limit individual LEDs.
* So we take minimum from all subnodes for safety of hardware.
*/
aggregated_led_microamp = is31->cdef->current_max;
for (i = 0; i < is31->cdef->num_leds; i++)
if (is31->leds[i].configured &&
is31->leds[i].max_microamp < aggregated_led_microamp)
aggregated_led_microamp = is31->leds[i].max_microamp;
if (is31->cdef->is_3196or3199)
regmap_write(is31->regmap, IS31FL3196_CONFIG2,
is31fl3196_microamp_to_cs(dev, aggregated_led_microamp) |
is31fl3196_db_to_gain(is31->audio_gain_db));
else
regmap_update_bits(is31->regmap, IS31FL3190_CURRENT, IS31FL3190_CURRENT_MASK,
is31fl3190_microamp_to_cs(dev, aggregated_led_microamp));
for (i = 0; i < is31->cdef->num_leds; i++) {
struct is31fl319x_led *led = &is31->leds[i];
if (!led->configured)
continue;
led->chip = is31;
led->cdev.brightness_set_blocking = is31->cdef->brightness_set;
err = devm_led_classdev_register(&client->dev, &led->cdev);
if (err < 0)
return err;
}
return 0;
}
/*
* i2c-core (and modalias) requires that id_table be properly filled,
* even though it is not used for DeviceTree based instantiation.
*/
static const struct i2c_device_id is31fl319x_id[] = {
{ "is31fl3190" },
{ "is31fl3191" },
{ "is31fl3193" },
{ "is31fl3196" },
{ "is31fl3199" },
{ "sn3190" },
{ "sn3191" },
{ "sn3193" },
{ "sn3196" },
{ "sn3199" },
{},
};
MODULE_DEVICE_TABLE(i2c, is31fl319x_id);
static struct i2c_driver is31fl319x_driver = {
.driver = {
.name = "leds-is31fl319x",
.of_match_table = of_is31fl319x_match,
},
.probe_new = is31fl319x_probe,
.id_table = is31fl319x_id,
};
module_i2c_driver(is31fl319x_driver);
MODULE_AUTHOR("H. Nikolaus Schaller <hns@goldelico.com>");
MODULE_AUTHOR("Andrey Utkin <andrey_utkin@fastmail.com>");
MODULE_DESCRIPTION("IS31FL319X LED driver");
MODULE_LICENSE("GPL v2");