AN30259A is a 3-channel LED driver which uses I2C. It supports timed operation via an internal PWM clock, and variable brightness. This driver offers support for basic hardware-based blinking and brightness control. The datasheet is freely available: https://www.alliedelec.com/m/d/a9d2b3ee87c2d1a535a41dd747b1c247.pdf Signed-off-by: Simon Shields <simon@xxxxxxxxxxxxx> --- drivers/leds/Kconfig | 10 ++ drivers/leds/Makefile | 1 + drivers/leds/leds-an30259a.c | 338 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 349 insertions(+) create mode 100644 drivers/leds/leds-an30259a.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 3e763d2a0cb3..80bed557cc6b 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -57,6 +57,16 @@ config LEDS_AAT1290 depends on PINCTRL help This option enables support for the LEDs on the AAT1290. + +config LEDS_AN30259A + tristate "LED support for Panasonic AN30259A" + depends on OF + depends on I2C + depends on LEDS_CLASS + help + This option enables support for the AN30259A 3-channel + LED driver. + config LEDS_APU tristate "Front panel LED support for PC Engines APU/APU2 boards" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 987884a5b9a5..44f9b42d1600 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_LEDS_88PM860X) += leds-88pm860x.o obj-$(CONFIG_LEDS_AAT1290) += leds-aat1290.o obj-$(CONFIG_LEDS_APU) += leds-apu.o obj-$(CONFIG_LEDS_AS3645A) += leds-as3645a.o +obj-$(CONFIG_LEDS_AN30259A) += leds-an30259a.o obj-$(CONFIG_LEDS_BCM6328) += leds-bcm6328.o obj-$(CONFIG_LEDS_BCM6358) += leds-bcm6358.o obj-$(CONFIG_LEDS_BD2802) += leds-bd2802.o diff --git a/drivers/leds/leds-an30259a.c b/drivers/leds/leds-an30259a.c new file mode 100644 index 000000000000..b51faf67e7de --- /dev/null +++ b/drivers/leds/leds-an30259a.c @@ -0,0 +1,338 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/i2c.h> +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/regmap.h> + +#define MAX_LEDS 3 + +#define REG_SRESET 0x00 +#define LED_SRESET (1 << 0) + +/* LED power registers */ +#define REG_LEDON 0x01 +#define LED_EN(x) (1 << (x)) +#define LED_SLOPE(x) (1 << ((x) + 4)) + +#define REG_LEDCC(x) (0x03 + (x)) + +/* slope control registers */ +#define REG_SLOPE(x) (0x06 + (x)) +#define LED_SLOPETIME1(x) (x) +#define LED_SLOPETIME2(x) ((x) << 4) + +#define REG_LEDCNT1(x) (0x09 + (4 * (x))) +#define LED_DUTYMAX(x) ((x) << 4) +#define LED_DUTYMID(x) (x) + +#define REG_LEDCNT2(x) (0x0A + (4 * (x))) +#define LED_DELAY(x) ((x) << 4) +#define LED_DUTYMIN(x) (x) + +/* detention time control (length of each slope step) */ +#define REG_LEDCNT3(x) (0x0B + (4 * (x))) +#define LED_DT1(x) (x) +#define LED_DT2(x) ((x) << 4) + +#define REG_LEDCNT4(x) (0x0C + (4 * (x))) +#define LED_DT3(x) (x) +#define LED_DT4(x) ((x) << 4) + +#define REG_MAX 0x14 + +#define BLINK_MAX_TIME 7500 /* ms */ + +struct an30259a; + +struct an30259a_led { + struct an30259a *chip; + struct led_classdev cdev; + int num; + char name[32]; +}; + +struct an30259a { + struct mutex mutex; + struct i2c_client *client; + struct an30259a_led leds[MAX_LEDS]; + struct regmap *regmap; +}; + +static u8 an30259a_get_duty_max(u8 brightness) +{ + u8 duty_max, floor, ceil; + + /* squash 8 bit number into 7-bit PWM range */ + duty_max = brightness >> 1; + + /* bottom 3 bits are always set for DUTYMAX + * figure out the closest value + */ + ceil = duty_max | 0x7; + floor = ceil - 0x8; + + if ((duty_max - floor) < (ceil - duty_max)) + duty_max = floor >> 3; + else + duty_max = ceil >> 3; + + return duty_max; +} + +static int an30259a_brightness(struct an30259a_led *led, + enum led_brightness brightness) +{ + int ret; + unsigned int ledon; + u8 duty_max; + + ret = regmap_read(led->chip->regmap, REG_LEDON, &ledon); + switch (brightness) { + case LED_OFF: + ledon &= ~LED_EN(led->num); + ledon &= ~LED_SLOPE(led->num); + break; + default: + ledon |= LED_EN(led->num); + duty_max = an30259a_get_duty_max(brightness & 0xff); + ret = regmap_write(led->chip->regmap, + REG_LEDCNT1(led->num), + LED_DUTYMAX(duty_max) | LED_DUTYMID(duty_max)); + if (ret) + return ret; + break; + } + ret = regmap_write(led->chip->regmap, REG_LEDON, + ledon); + if (ret) + return ret; + + ret = regmap_write(led->chip->regmap, REG_LEDCC(led->num), + brightness & 0xff); + if (ret) + return ret; + + return ret; +} + +static int an30259a_blink(struct an30259a_led *led, + unsigned long *poff, unsigned long *pon) +{ + int ret, num = led->num; + unsigned int ledon; + unsigned long off = *poff, on = *pon; + + /* slope time - multiples of 500ms only */ + off -= off % 500; + if (!off) + off += 500; + else if (off > BLINK_MAX_TIME) + off = BLINK_MAX_TIME; + *poff = off; + off /= 500; + + on -= on % 500; + if (!on) + on += 500; + else if (on > BLINK_MAX_TIME) + on = BLINK_MAX_TIME; + *pon = on; + on /= 500; + + /* duty min should be zero (=off), delay should be zero */ + ret = regmap_write(led->chip->regmap, REG_LEDCNT2(num), + LED_DELAY(0) | LED_DUTYMIN(0)); + if (ret) + return ret; + + /* reset detention time (no "breathing" effect) */ + ret = regmap_write(led->chip->regmap, REG_LEDCNT3(num), + LED_DT1(0) | LED_DT2(0)); + if (ret) + return ret; + ret = regmap_write(led->chip->regmap, REG_LEDCNT4(num), + LED_DT3(0) | LED_DT4(0)); + if (ret) + return ret; + + /* slope time controls on/off cycle length */ + ret = regmap_write(led->chip->regmap, REG_SLOPE(num), + LED_SLOPETIME1(off) | LED_SLOPETIME2(on)); + if (ret) + return ret; + + /* Finally, enable slope mode. */ + ret = regmap_read(led->chip->regmap, REG_LEDON, &ledon); + if (ret) + return ret; + ledon |= LED_SLOPE(num); + return regmap_write(led->chip->regmap, REG_LEDON, + ledon); +} + +static int an30259a_led_set(struct led_classdev *cdev, + enum led_brightness value) +{ + struct an30259a_led *led; + int ret; + + led = container_of(cdev, struct an30259a_led, cdev); + + mutex_lock(&led->chip->mutex); + + ret = an30259a_brightness(led, value); + + mutex_unlock(&led->chip->mutex); + return ret; +} + +static int an30259a_blink_set(struct led_classdev *cdev, + unsigned long *delay_off, unsigned long *delay_on) +{ + struct an30259a_led *led; + int ret; + + led = container_of(cdev, struct an30259a_led, cdev); + + mutex_lock(&led->chip->mutex); + + ret = an30259a_blink(led, delay_off, delay_on); + + mutex_unlock(&led->chip->mutex); + return ret; +} + +static struct led_platform_data * +an30259a_dt_init(struct i2c_client *client) +{ + struct led_platform_data *pdata; + struct device_node *np = client->dev.of_node, *child; + struct led_info *leds; + int count; + int res; + + count = of_get_child_count(np); + if (!count || count > MAX_LEDS) + return ERR_PTR(-EINVAL); + + leds = devm_kzalloc(&client->dev, sizeof(*leds) * count, GFP_KERNEL); + if (!leds) + return ERR_PTR(-ENOMEM); + + for_each_child_of_node(np, child) { + u32 source; + + res = of_property_read_u32(child, "led-sources", &source); + if ((res != 0) || source >= MAX_LEDS) + continue; + + leds[source].name = of_get_property(child, "label", NULL); + leds[source].default_trigger = + of_get_property(child, "linux,default-trigger", NULL); + } + + pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return ERR_PTR(-ENOMEM); + + pdata->leds = leds; + pdata->num_leds = MAX_LEDS; + + return pdata; +} + +static const struct regmap_config an30259a_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = REG_MAX, +}; + +static int an30259a_probe(struct i2c_client *client) +{ + struct led_platform_data *pdata; + struct an30259a *chip; + int i, err; + + pdata = an30259a_dt_init(client); + if (IS_ERR(pdata)) + return PTR_ERR(pdata); + + chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + mutex_init(&chip->mutex); + chip->client = client; + chip->regmap = devm_regmap_init_i2c(client, &an30259a_regmap_config); + + i2c_set_clientdata(client, chip); + + /* Reset the IC */ + regmap_write(chip->regmap, REG_SRESET, LED_SRESET); + + for (i = 0; i < pdata->num_leds; i++) { + chip->leds[i].num = i; + chip->leds[i].chip = chip; + + if (pdata->leds[i].name) + snprintf(chip->leds[i].name, sizeof(chip->leds[i].name), + "an30259a:%s", pdata->leds[i].name); + else + snprintf(chip->leds[i].name, sizeof(chip->leds[i].name), + "an30259a:%d:%.2x:%d", + client->adapter->nr, client->addr, i); + if (pdata->leds[i].default_trigger) + chip->leds[i].cdev.default_trigger = + pdata->leds[i].default_trigger; + + chip->leds[i].cdev.name = chip->leds[i].name; + + chip->leds[i].cdev.brightness_set_blocking = an30259a_led_set; + chip->leds[i].cdev.blink_set = an30259a_blink_set; + + err = led_classdev_register(&client->dev, &chip->leds[i].cdev); + if (err < 0) + goto exit; + } + return 0; + +exit: + while (i--) + led_classdev_unregister(&chip->leds[i].cdev); + return err; +} + +static int an30259a_remove(struct i2c_client *client) +{ + struct an30259a *chip = i2c_get_clientdata(client); + int i; + + for (i = 0; i < MAX_LEDS; i++) + led_classdev_unregister(&chip->leds[i].cdev); + + return 0; +} + +static const struct of_device_id an30259a_match_table[] = { + { .compatible = "panasonic,an30259a", }, + { /* sentinel */ }, +}; + +MODULE_DEVICE_TABLE(of, an30259a_match_table); + +static struct i2c_driver an30259a_driver = { + .driver = { + .name = "leds-an32059a", + .of_match_table = of_match_ptr(an30259a_match_table), + }, + .probe_new = an30259a_probe, + .remove = an30259a_remove, +}; + +module_i2c_driver(an30259a_driver); + +MODULE_AUTHOR("Simon Shields <simon@xxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("AN32059A LED driver"); +MODULE_LICENSE("GPL v2"); -- 2.16.2 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
