diff options
Diffstat (limited to 'drivers/leds/leds-tlc591xx.c')
| -rw-r--r-- | drivers/leds/leds-tlc591xx.c | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/drivers/leds/leds-tlc591xx.c b/drivers/leds/leds-tlc591xx.c new file mode 100644 index 000000000000..de16c29d7895 --- /dev/null +++ b/drivers/leds/leds-tlc591xx.c @@ -0,0 +1,300 @@ +/* + * Copyright 2014 Belkin Inc. + * Copyright 2015 Andrew Lunn <andrew@lunn.ch> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + */ + +#include <linux/i2c.h> +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <linux/workqueue.h> + +#define TLC591XX_MAX_LEDS 16 + +#define TLC591XX_REG_MODE1 0x00 +#define MODE1_RESPON_ADDR_MASK 0xF0 +#define MODE1_NORMAL_MODE (0 << 4) +#define MODE1_SPEED_MODE (1 << 4) + +#define TLC591XX_REG_MODE2 0x01 +#define MODE2_DIM (0 << 5) +#define MODE2_BLINK (1 << 5) +#define MODE2_OCH_STOP (0 << 3) +#define MODE2_OCH_ACK (1 << 3) + +#define TLC591XX_REG_PWM(x) (0x02 + (x)) + +#define TLC591XX_REG_GRPPWM 0x12 +#define TLC591XX_REG_GRPFREQ 0x13 + +/* LED Driver Output State, determine the source that drives LED outputs */ +#define LEDOUT_OFF 0x0 /* Output LOW */ +#define LEDOUT_ON 0x1 /* Output HI-Z */ +#define LEDOUT_DIM 0x2 /* Dimming */ +#define LEDOUT_BLINK 0x3 /* Blinking */ +#define LEDOUT_MASK 0x3 + +#define ldev_to_led(c) container_of(c, struct tlc591xx_led, ldev) +#define work_to_led(work) container_of(work, struct tlc591xx_led, work) + +struct tlc591xx_led { + bool active; + unsigned int led_no; + struct led_classdev ldev; + struct work_struct work; + struct tlc591xx_priv *priv; +}; + +struct tlc591xx_priv { + struct tlc591xx_led leds[TLC591XX_MAX_LEDS]; + struct regmap *regmap; + unsigned int reg_ledout_offset; +}; + +struct tlc591xx { + unsigned int max_leds; + unsigned int reg_ledout_offset; +}; + +static const struct tlc591xx tlc59116 = { + .max_leds = 16, + .reg_ledout_offset = 0x14, +}; + +static const struct tlc591xx tlc59108 = { + .max_leds = 8, + .reg_ledout_offset = 0x0c, +}; + +static int +tlc591xx_set_mode(struct regmap *regmap, u8 mode) +{ + int err; + u8 val; + + err = regmap_write(regmap, TLC591XX_REG_MODE1, MODE1_NORMAL_MODE); + if (err) + return err; + + val = MODE2_OCH_STOP | mode; + + return regmap_write(regmap, TLC591XX_REG_MODE2, val); +} + +static int +tlc591xx_set_ledout(struct tlc591xx_priv *priv, struct tlc591xx_led *led, + u8 val) +{ + unsigned int i = (led->led_no % 4) * 2; + unsigned int mask = LEDOUT_MASK << i; + unsigned int addr = priv->reg_ledout_offset + (led->led_no >> 2); + + val = val << i; + + return regmap_update_bits(priv->regmap, addr, mask, val); +} + +static int +tlc591xx_set_pwm(struct tlc591xx_priv *priv, struct tlc591xx_led *led, + u8 brightness) +{ + u8 pwm = TLC591XX_REG_PWM(led->led_no); + + return regmap_write(priv->regmap, pwm, brightness); +} + +static void +tlc591xx_led_work(struct work_struct *work) +{ + struct tlc591xx_led *led = work_to_led(work); + struct tlc591xx_priv *priv = led->priv; + enum led_brightness brightness = led->ldev.brightness; + int err; + + switch (brightness) { + case 0: + err = tlc591xx_set_ledout(priv, led, LEDOUT_OFF); + break; + case LED_FULL: + err = tlc591xx_set_ledout(priv, led, LEDOUT_ON); + break; + default: + err = tlc591xx_set_ledout(priv, led, LEDOUT_DIM); + if (!err) + err = tlc591xx_set_pwm(priv, led, brightness); + } + + if (err) + dev_err(led->ldev.dev, "Failed setting brightness\n"); +} + +static void +tlc591xx_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + struct tlc591xx_led *led = ldev_to_led(led_cdev); + + led->ldev.brightness = brightness; + schedule_work(&led->work); +} + +static void +tlc591xx_destroy_devices(struct tlc591xx_priv *priv, unsigned int j) +{ + int i = j; + + while (--i >= 0) { + if (priv->leds[i].active) { + led_classdev_unregister(&priv->leds[i].ldev); + cancel_work_sync(&priv->leds[i].work); + } + } +} + +static int +tlc591xx_configure(struct device *dev, + struct tlc591xx_priv *priv, + const struct tlc591xx *tlc591xx) +{ + unsigned int i; + int err = 0; + + tlc591xx_set_mode(priv->regmap, MODE2_DIM); + for (i = 0; i < TLC591XX_MAX_LEDS; i++) { + struct tlc591xx_led *led = &priv->leds[i]; + + if (!led->active) + continue; + + led->priv = priv; + led->led_no = i; + led->ldev.brightness_set = tlc591xx_brightness_set; + led->ldev.max_brightness = LED_FULL; + INIT_WORK(&led->work, tlc591xx_led_work); + err = led_classdev_register(dev, &led->ldev); + if (err < 0) { + dev_err(dev, "couldn't register LED %s\n", + led->ldev.name); + goto exit; + } + } + + return 0; + +exit: + tlc591xx_destroy_devices(priv, i); + return err; +} + +static const struct regmap_config tlc591xx_regmap = { + .reg_bits = 8, + .val_bits = 8, + .max_register = 0x1e, +}; + +static const struct of_device_id of_tlc591xx_leds_match[] = { + { .compatible = "ti,tlc59116", + .data = &tlc59116 }, + { .compatible = "ti,tlc59108", + .data = &tlc59108 }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_tlc591xx_leds_match); + +static int +tlc591xx_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device_node *np = client->dev.of_node, *child; + struct device *dev = &client->dev; + const struct of_device_id *match; + const struct tlc591xx *tlc591xx; + struct tlc591xx_priv *priv; + int err, count, reg; + + match = of_match_device(of_tlc591xx_leds_match, dev); + if (!match) + return -ENODEV; + + tlc591xx = match->data; + if (!np) + return -ENODEV; + + count = of_get_child_count(np); + if (!count || count > tlc591xx->max_leds) + return -EINVAL; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_BYTE_DATA)) + return -EIO; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->regmap = devm_regmap_init_i2c(client, &tlc591xx_regmap); + if (IS_ERR(priv->regmap)) { + err = PTR_ERR(priv->regmap); + dev_err(dev, "Failed to allocate register map: %d\n", err); + return err; + } + priv->reg_ledout_offset = tlc591xx->reg_ledout_offset; + + i2c_set_clientdata(client, priv); + + for_each_child_of_node(np, child) { + err = of_property_read_u32(child, "reg", ®); + if (err) + return err; + if (reg < 0 || reg >= tlc591xx->max_leds) + return -EINVAL; + if (priv->leds[reg].active) + return -EINVAL; + priv->leds[reg].active = true; + priv->leds[reg].ldev.name = + of_get_property(child, "label", NULL) ? : child->name; + priv->leds[reg].ldev.default_trigger = + of_get_property(child, "linux,default-trigger", NULL); + } + return tlc591xx_configure(dev, priv, tlc591xx); +} + +static int +tlc591xx_remove(struct i2c_client *client) +{ + struct tlc591xx_priv *priv = i2c_get_clientdata(client); + + tlc591xx_destroy_devices(priv, TLC591XX_MAX_LEDS); + + return 0; +} + +static const struct i2c_device_id tlc591xx_id[] = { + { "tlc59116" }, + { "tlc59108" }, + {}, +}; +MODULE_DEVICE_TABLE(i2c, tlc591xx_id); + +static struct i2c_driver tlc591xx_driver = { + .driver = { + .name = "tlc591xx", + .of_match_table = of_match_ptr(of_tlc591xx_leds_match), + }, + .probe = tlc591xx_probe, + .remove = tlc591xx_remove, + .id_table = tlc591xx_id, +}; + +module_i2c_driver(tlc591xx_driver); + +MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("TLC591XX LED driver"); |