// SPDX-License-Identifier: GPL-2.0+
// Driver for Awinic AW2013 3-channel LED driver
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/regulator/consumer.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/regmap.h>
#define AW2013_MAX_LEDS 3
/* Reset and ID register */
#define AW2013_RSTR 0x00
#define AW2013_RSTR_RESET 0x55
#define AW2013_RSTR_CHIP_ID 0x33
/* Global control register */
#define AW2013_GCR 0x01
#define AW2013_GCR_ENABLE BIT(0)
/* LED channel enable register */
#define AW2013_LCTR 0x30
#define AW2013_LCTR_LE(x) BIT((x))
/* LED channel control registers */
#define AW2013_LCFG(x) (0x31 + (x))
#define AW2013_LCFG_IMAX_MASK (BIT(0) | BIT(1)) // Should be 0-3
#define AW2013_LCFG_MD BIT(4)
#define AW2013_LCFG_FI BIT(5)
#define AW2013_LCFG_FO BIT(6)
/* LED channel PWM registers */
#define AW2013_REG_PWM(x) (0x34 + (x))
/* LED channel timing registers */
#define AW2013_LEDT0(x) (0x37 + (x) * 3)
#define AW2013_LEDT0_T1(x) ((x) << 4) // Should be 0-7
#define AW2013_LEDT0_T2(x) (x) // Should be 0-5
#define AW2013_LEDT1(x) (0x38 + (x) * 3)
#define AW2013_LEDT1_T3(x) ((x) << 4) // Should be 0-7
#define AW2013_LEDT1_T4(x) (x) // Should be 0-7
#define AW2013_LEDT2(x) (0x39 + (x) * 3)
#define AW2013_LEDT2_T0(x) ((x) << 4) // Should be 0-8
#define AW2013_LEDT2_REPEAT(x) (x) // Should be 0-15
#define AW2013_REG_MAX 0x77
#define AW2013_TIME_STEP 130 /* ms */
struct aw2013;
struct aw2013_led {
struct aw2013 *chip;
struct led_classdev cdev;
u32 num;
unsigned int imax;
};
struct aw2013 {
struct mutex mutex; /* held when writing to registers */
struct regulator_bulk_data regulators[2];
struct i2c_client *client;
struct aw2013_led leds[AW2013_MAX_LEDS];
struct regmap *regmap;
int num_leds;
bool enabled;
};
static int aw2013_chip_init(struct aw2013 *chip)
{
int i, ret;
ret = regmap_write(chip->regmap, AW2013_GCR, AW2013_GCR_ENABLE);
if (ret) {
dev_err(&chip->client->dev, "Failed to enable the chip: %d\n",
ret);
return ret;
}
for (i = 0; i < chip->num_leds; i++) {
ret = regmap_update_bits(chip->regmap,
AW2013_LCFG(chip->leds[i].num),
AW2013_LCFG_IMAX_MASK,
chip->leds[i].imax);
if (ret) {
dev_err(&chip->client->dev,
"Failed to set maximum current for led %d: %d\n",
chip->leds[i].num, ret);
return ret;
}
}
return ret;
}
static void aw2013_chip_disable(struct aw2013 *chip)
{
int ret;
if (!chip->enabled)
return;
regmap_write(chip->regmap, AW2013_GCR, 0);
ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
chip->regulators);
if (ret) {
dev_err(&chip->client->dev,
"Failed to disable regulators: %d\n", ret);
return;
}
chip->enabled = false;
}
static int aw2013_chip_enable(struct aw2013 *chip)
{
int ret;
if (chip->enabled)
return 0;
ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators),
chip->regulators);
if (ret) {
dev_err(&chip->client->dev,
"Failed to enable regulators: %d\n", ret);
return ret;
}
chip->enabled = true;
ret = aw2013_chip_init(chip);
if (ret)
aw2013_chip_disable(chip);
return ret;
}
static bool aw2013_chip_in_use(struct aw2013 *chip)
{
int i;
for (i = 0; i < chip->num_leds; i++)
if (chip->leds[i].cdev.brightness)
return true;
return false;
}
static int aw2013_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev);
int ret, num;
mutex_lock(&led->chip->mutex);
if (aw2013_chip_in_use(led->chip)) {
ret = aw2013_chip_enable(led->chip);
if (ret)
goto error;
}
num = led->num;
ret = regmap_write(led->chip->regmap, AW2013_REG_PWM(num), brightness);
if (ret)
goto error;
if (brightness) {
ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR,
AW2013_LCTR_LE(num), 0xFF);
} else {
ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR,
AW2013_LCTR_LE(num), 0);
if (ret)
goto error;
ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num),
AW2013_LCFG_MD, 0);
}
if (ret)
goto error;
if (!aw2013_chip_in_use(led->chip))
aw2013_chip_disable(led->chip);
error:
mutex_unlock(&led->chip->mutex);
return ret;
}
static int aw2013_blink_set(struct led_classdev *cdev,
unsigned long *delay_on, unsigned long *delay_off)
{
struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev);
int ret, num = led->num;
unsigned long off = 0, on = 0;
/* If no blink specified, default to 1 Hz. */
if (!*delay_off && !*delay_on) {
*delay_off = 500;
*delay_on = 500;
}
if (!led->cdev.brightness) {
led->cdev.brightness = LED_FULL;
ret = aw2013_brightness_set(&led->cdev, led->cdev.brightness);
if (ret)
return ret;
}
/* Never on - just set to off */
if (!*delay_on) {
led->cdev.brightness = LED_OFF;
return aw2013_brightness_set(&led->cdev, LED_OFF);
}
mutex_lock(&led->chip->mutex);
/* Never off - brightness is already set, disable blinking */
if (!*delay_off) {
ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num),
AW2013_LCFG_MD, 0);
goto out;
}
/* Convert into values the HW will understand. */
off = min(5, ilog2((*delay_off - 1) / AW2013_TIME_STEP) + 1);
on = min(7, ilog2((*delay_on - 1) / AW2013_TIME_STEP) + 1);
*delay_off = BIT(off) * AW2013_TIME_STEP;
*delay_on = BIT(on) * AW2013_TIME_STEP;
/* Set timings */
ret = regmap_write(led->chip->regmap,
AW2013_LEDT0(num), AW2013_LEDT0_T2(on));
if (ret)
goto out;
ret = regmap_write(led->chip->regmap,
AW2013_LEDT1(num), AW2013_LEDT1_T4(off));
if (ret)
goto out;
/* Finally, enable the LED */
ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num),
AW2013_LCFG_MD, 0xFF);
if (ret)
goto out;
ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR,
AW2013_LCTR_LE(num), 0xFF);
out:
mutex_unlock(&led->chip->mutex);
return ret;
}
static int aw2013_probe_dt(struct aw2013 *chip)
{
struct device_node *np = dev_of_node(&chip->client->dev);
int count, ret = 0, i = 0;
struct aw2013_led *led;
count = of_get_available_child_count(np);
if (!count || count > AW2013_MAX_LEDS)
return -EINVAL;
regmap_write(chip->regmap, AW2013_RSTR, AW2013_RSTR_RESET);
for_each_available_child_of_node_scoped(np, child) {
struct led_init_data init_data = {};
u32 source;
u32 imax;
ret = of_property_read_u32(child, "reg", &source);
if (ret != 0 || source >= AW2013_MAX_LEDS) {
dev_err(&chip->client->dev,
"Couldn't read LED address: %d\n", ret);
count--;
continue;
}
led = &chip->leds[i];
led->num = source;
led->chip = chip;
init_data.fwnode = of_fwnode_handle(child);
if (!of_property_read_u32(child, "led-max-microamp", &imax)) {
led->imax = min_t(u32, imax / 5000, 3);
} else {
led->imax = 1; // 5mA
dev_info(&chip->client->dev,
"DT property led-max-microamp is missing\n");
}
led->cdev.brightness_set_blocking = aw2013_brightness_set;
led->cdev.blink_set = aw2013_blink_set;
ret = devm_led_classdev_register_ext(&chip->client->dev,
&led->cdev, &init_data);
if (ret < 0)
return ret;
i++;
}
if (!count)
return -EINVAL;
chip->num_leds = i;
return 0;
}
static void aw2013_chip_disable_action(void *data)
{
aw2013_chip_disable(data);
}
static const struct regmap_config aw2013_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = AW2013_REG_MAX,
};
static int aw2013_probe(struct i2c_client *client)
{
struct aw2013 *chip;
int ret;
unsigned int chipid;
chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
ret = devm_mutex_init(&client->dev, &chip->mutex);
if (ret)
return ret;
mutex_lock(&chip->mutex);
chip->client = client;
i2c_set_clientdata(client, chip);
chip->regmap = devm_regmap_init_i2c(client, &aw2013_regmap_config);
if (IS_ERR(chip->regmap)) {
ret = PTR_ERR(chip->regmap);
dev_err(&client->dev, "Failed to allocate register map: %d\n",
ret);
goto error;
}
chip->regulators[0].supply = "vcc";
chip->regulators[1].supply = "vio";
ret = devm_regulator_bulk_get(&client->dev,
ARRAY_SIZE(chip->regulators),
chip->regulators);
if (ret < 0) {
if (ret != -EPROBE_DEFER)
dev_err(&client->dev,
"Failed to request regulators: %d\n", ret);
goto error;
}
ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators),
chip->regulators);
if (ret) {
dev_err(&client->dev,
"Failed to enable regulators: %d\n", ret);
goto error;
}
ret = regmap_read(chip->regmap, AW2013_RSTR, &chipid);
if (ret) {
dev_err(&client->dev, "Failed to read chip ID: %d\n",
ret);
goto error_reg;
}
if (chipid != AW2013_RSTR_CHIP_ID) {
dev_err(&client->dev, "Chip reported wrong ID: %x\n",
chipid);
ret = -ENODEV;
goto error_reg;
}
ret = devm_add_action(&client->dev, aw2013_chip_disable_action, chip);
if (ret)
goto error_reg;
ret = aw2013_probe_dt(chip);
if (ret < 0)
goto error_reg;
ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
chip->regulators);
if (ret) {
dev_err(&client->dev,
"Failed to disable regulators: %d\n", ret);
goto error;
}
mutex_unlock(&chip->mutex);
return 0;
error_reg:
regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
chip->regulators);
error:
mutex_unlock(&chip->mutex);
return ret;
}
static const struct of_device_id aw2013_match_table[] = {
{ .compatible = "awinic,aw2013", },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, aw2013_match_table);
static struct i2c_driver aw2013_driver = {
.driver = {
.name = "leds-aw2013",
.of_match_table = aw2013_match_table,
},
.probe = aw2013_probe,
};
module_i2c_driver(aw2013_driver);
MODULE_AUTHOR("Nikita Travkin <[email protected]>");
MODULE_DESCRIPTION("AW2013 LED driver");
MODULE_LICENSE("GPL v2");
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