diff options
Diffstat (limited to 'drivers/leds/leds-lp8860.c')
-rw-r--r-- | drivers/leds/leds-lp8860.c | 493 |
1 files changed, 493 insertions, 0 deletions
diff --git a/drivers/leds/leds-lp8860.c b/drivers/leds/leds-lp8860.c new file mode 100644 index 000000000..8c2b7fbe2 --- /dev/null +++ b/drivers/leds/leds-lp8860.c @@ -0,0 +1,493 @@ +/* + * TI LP8860 4-Channel LED Driver + * + * Copyright (C) 2014 Texas Instruments + * + * Author: Dan Murphy <dmurphy@ti.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + */ + +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/leds.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/gpio/consumer.h> +#include <linux/slab.h> + +#define LP8860_DISP_CL1_BRT_MSB 0x00 +#define LP8860_DISP_CL1_BRT_LSB 0x01 +#define LP8860_DISP_CL1_CURR_MSB 0x02 +#define LP8860_DISP_CL1_CURR_LSB 0x03 +#define LP8860_CL2_BRT_MSB 0x04 +#define LP8860_CL2_BRT_LSB 0x05 +#define LP8860_CL2_CURRENT 0x06 +#define LP8860_CL3_BRT_MSB 0x07 +#define LP8860_CL3_BRT_LSB 0x08 +#define LP8860_CL3_CURRENT 0x09 +#define LP8860_CL4_BRT_MSB 0x0a +#define LP8860_CL4_BRT_LSB 0x0b +#define LP8860_CL4_CURRENT 0x0c +#define LP8860_CONFIG 0x0d +#define LP8860_STATUS 0x0e +#define LP8860_FAULT 0x0f +#define LP8860_LED_FAULT 0x10 +#define LP8860_FAULT_CLEAR 0x11 +#define LP8860_ID 0x12 +#define LP8860_TEMP_MSB 0x13 +#define LP8860_TEMP_LSB 0x14 +#define LP8860_DISP_LED_CURR_MSB 0x15 +#define LP8860_DISP_LED_CURR_LSB 0x16 +#define LP8860_DISP_LED_PWM_MSB 0x17 +#define LP8860_DISP_LED_PWM_LSB 0x18 +#define LP8860_EEPROM_CNTRL 0x19 +#define LP8860_EEPROM_UNLOCK 0x1a + +#define LP8860_EEPROM_REG_0 0x60 +#define LP8860_EEPROM_REG_1 0x61 +#define LP8860_EEPROM_REG_2 0x62 +#define LP8860_EEPROM_REG_3 0x63 +#define LP8860_EEPROM_REG_4 0x64 +#define LP8860_EEPROM_REG_5 0x65 +#define LP8860_EEPROM_REG_6 0x66 +#define LP8860_EEPROM_REG_7 0x67 +#define LP8860_EEPROM_REG_8 0x68 +#define LP8860_EEPROM_REG_9 0x69 +#define LP8860_EEPROM_REG_10 0x6a +#define LP8860_EEPROM_REG_11 0x6b +#define LP8860_EEPROM_REG_12 0x6c +#define LP8860_EEPROM_REG_13 0x6d +#define LP8860_EEPROM_REG_14 0x6e +#define LP8860_EEPROM_REG_15 0x6f +#define LP8860_EEPROM_REG_16 0x70 +#define LP8860_EEPROM_REG_17 0x71 +#define LP8860_EEPROM_REG_18 0x72 +#define LP8860_EEPROM_REG_19 0x73 +#define LP8860_EEPROM_REG_20 0x74 +#define LP8860_EEPROM_REG_21 0x75 +#define LP8860_EEPROM_REG_22 0x76 +#define LP8860_EEPROM_REG_23 0x77 +#define LP8860_EEPROM_REG_24 0x78 + +#define LP8860_LOCK_EEPROM 0x00 +#define LP8860_UNLOCK_EEPROM 0x01 +#define LP8860_PROGRAM_EEPROM 0x02 +#define LP8860_EEPROM_CODE_1 0x08 +#define LP8860_EEPROM_CODE_2 0xba +#define LP8860_EEPROM_CODE_3 0xef + +#define LP8860_CLEAR_FAULTS 0x01 + +#define LP8860_DISP_LED_NAME "display_cluster" + +/** + * struct lp8860_led - + * @lock - Lock for reading/writing the device + * @work - Work item used to off load the brightness register writes + * @client - Pointer to the I2C client + * @led_dev - led class device pointer + * @regmap - Devices register map + * @eeprom_regmap - EEPROM register map + * @enable_gpio - VDDIO/EN gpio to enable communication interface + * @regulator - LED supply regulator pointer + * @brightness - Current brightness value requested + * @label - LED label +**/ +struct lp8860_led { + struct mutex lock; + struct work_struct work; + struct i2c_client *client; + struct led_classdev led_dev; + struct regmap *regmap; + struct regmap *eeprom_regmap; + struct gpio_desc *enable_gpio; + struct regulator *regulator; + enum led_brightness brightness; + const char *label; +}; + +struct lp8860_eeprom_reg { + uint8_t reg; + uint8_t value; +}; + +static struct lp8860_eeprom_reg lp8860_eeprom_disp_regs[] = { + { LP8860_EEPROM_REG_0, 0xed }, + { LP8860_EEPROM_REG_1, 0xdf }, + { LP8860_EEPROM_REG_2, 0xdc }, + { LP8860_EEPROM_REG_3, 0xf0 }, + { LP8860_EEPROM_REG_4, 0xdf }, + { LP8860_EEPROM_REG_5, 0xe5 }, + { LP8860_EEPROM_REG_6, 0xf2 }, + { LP8860_EEPROM_REG_7, 0x77 }, + { LP8860_EEPROM_REG_8, 0x77 }, + { LP8860_EEPROM_REG_9, 0x71 }, + { LP8860_EEPROM_REG_10, 0x3f }, + { LP8860_EEPROM_REG_11, 0xb7 }, + { LP8860_EEPROM_REG_12, 0x17 }, + { LP8860_EEPROM_REG_13, 0xef }, + { LP8860_EEPROM_REG_14, 0xb0 }, + { LP8860_EEPROM_REG_15, 0x87 }, + { LP8860_EEPROM_REG_16, 0xce }, + { LP8860_EEPROM_REG_17, 0x72 }, + { LP8860_EEPROM_REG_18, 0xe5 }, + { LP8860_EEPROM_REG_19, 0xdf }, + { LP8860_EEPROM_REG_20, 0x35 }, + { LP8860_EEPROM_REG_21, 0x06 }, + { LP8860_EEPROM_REG_22, 0xdc }, + { LP8860_EEPROM_REG_23, 0x88 }, + { LP8860_EEPROM_REG_24, 0x3E }, +}; + +static int lp8860_unlock_eeprom(struct lp8860_led *led, int lock) +{ + int ret; + + mutex_lock(&led->lock); + + if (lock == LP8860_UNLOCK_EEPROM) { + ret = regmap_write(led->regmap, + LP8860_EEPROM_UNLOCK, + LP8860_EEPROM_CODE_1); + if (ret) { + dev_err(&led->client->dev, "EEPROM Unlock failed\n"); + goto out; + } + + ret = regmap_write(led->regmap, + LP8860_EEPROM_UNLOCK, + LP8860_EEPROM_CODE_2); + if (ret) { + dev_err(&led->client->dev, "EEPROM Unlock failed\n"); + goto out; + } + ret = regmap_write(led->regmap, + LP8860_EEPROM_UNLOCK, + LP8860_EEPROM_CODE_3); + if (ret) { + dev_err(&led->client->dev, "EEPROM Unlock failed\n"); + goto out; + } + } else { + ret = regmap_write(led->regmap, + LP8860_EEPROM_UNLOCK, + LP8860_LOCK_EEPROM); + } + +out: + mutex_unlock(&led->lock); + return ret; +} + +static int lp8860_fault_check(struct lp8860_led *led) +{ + int ret, fault; + unsigned int read_buf; + + ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf); + if (ret) + goto out; + + fault = read_buf; + + ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf); + if (ret) + goto out; + + fault |= read_buf; + + /* Attempt to clear any faults */ + if (fault) + ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR, + LP8860_CLEAR_FAULTS); +out: + return ret; +} + +static void lp8860_led_brightness_work(struct work_struct *work) +{ + struct lp8860_led *led = container_of(work, struct lp8860_led, work); + int ret; + int disp_brightness = led->brightness * 255; + + mutex_lock(&led->lock); + + ret = lp8860_fault_check(led); + if (ret) { + dev_err(&led->client->dev, "Cannot read/clear faults\n"); + goto out; + } + + ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB, + (disp_brightness & 0xff00) >> 8); + if (ret) { + dev_err(&led->client->dev, "Cannot write CL1 MSB\n"); + goto out; + } + + ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB, + disp_brightness & 0xff); + if (ret) { + dev_err(&led->client->dev, "Cannot write CL1 LSB\n"); + goto out; + } +out: + mutex_unlock(&led->lock); +} + +static void lp8860_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brt_val) +{ + struct lp8860_led *led = + container_of(led_cdev, struct lp8860_led, led_dev); + + led->brightness = brt_val; + schedule_work(&led->work); +} + +static int lp8860_init(struct lp8860_led *led) +{ + unsigned int read_buf; + int ret, i, reg_count; + + if (led->enable_gpio) + gpiod_direction_output(led->enable_gpio, 1); + + ret = lp8860_fault_check(led); + if (ret) + goto out; + + ret = regmap_read(led->regmap, LP8860_STATUS, &read_buf); + if (ret) + goto out; + + ret = lp8860_unlock_eeprom(led, LP8860_UNLOCK_EEPROM); + if (ret) { + dev_err(&led->client->dev, "Failed unlocking EEPROM\n"); + goto out; + } + + reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs) / sizeof(lp8860_eeprom_disp_regs[0]); + for (i = 0; i < reg_count; i++) { + ret = regmap_write(led->eeprom_regmap, + lp8860_eeprom_disp_regs[i].reg, + lp8860_eeprom_disp_regs[i].value); + if (ret) { + dev_err(&led->client->dev, "Failed writing EEPROM\n"); + goto out; + } + } + + ret = lp8860_unlock_eeprom(led, LP8860_LOCK_EEPROM); + if (ret) + goto out; + + ret = regmap_write(led->regmap, + LP8860_EEPROM_CNTRL, + LP8860_PROGRAM_EEPROM); + if (ret) + dev_err(&led->client->dev, "Failed programming EEPROM\n"); +out: + if (ret) + if (led->enable_gpio) + gpiod_direction_output(led->enable_gpio, 0); + return ret; +} + +static struct reg_default lp8860_reg_defs[] = { + { LP8860_DISP_CL1_BRT_MSB, 0x00}, + { LP8860_DISP_CL1_BRT_LSB, 0x00}, + { LP8860_DISP_CL1_CURR_MSB, 0x00}, + { LP8860_DISP_CL1_CURR_LSB, 0x00}, + { LP8860_CL2_BRT_MSB, 0x00}, + { LP8860_CL2_BRT_LSB, 0x00}, + { LP8860_CL2_CURRENT, 0x00}, + { LP8860_CL3_BRT_MSB, 0x00}, + { LP8860_CL3_BRT_LSB, 0x00}, + { LP8860_CL3_CURRENT, 0x00}, + { LP8860_CL4_BRT_MSB, 0x00}, + { LP8860_CL4_BRT_LSB, 0x00}, + { LP8860_CL4_CURRENT, 0x00}, + { LP8860_CONFIG, 0x00}, + { LP8860_FAULT_CLEAR, 0x00}, + { LP8860_EEPROM_CNTRL, 0x80}, + { LP8860_EEPROM_UNLOCK, 0x00}, +}; + +static const struct regmap_config lp8860_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + + .max_register = LP8860_EEPROM_UNLOCK, + .reg_defaults = lp8860_reg_defs, + .num_reg_defaults = ARRAY_SIZE(lp8860_reg_defs), + .cache_type = REGCACHE_NONE, +}; + +static struct reg_default lp8860_eeprom_defs[] = { + { LP8860_EEPROM_REG_0, 0x00 }, + { LP8860_EEPROM_REG_1, 0x00 }, + { LP8860_EEPROM_REG_2, 0x00 }, + { LP8860_EEPROM_REG_3, 0x00 }, + { LP8860_EEPROM_REG_4, 0x00 }, + { LP8860_EEPROM_REG_5, 0x00 }, + { LP8860_EEPROM_REG_6, 0x00 }, + { LP8860_EEPROM_REG_7, 0x00 }, + { LP8860_EEPROM_REG_8, 0x00 }, + { LP8860_EEPROM_REG_9, 0x00 }, + { LP8860_EEPROM_REG_10, 0x00 }, + { LP8860_EEPROM_REG_11, 0x00 }, + { LP8860_EEPROM_REG_12, 0x00 }, + { LP8860_EEPROM_REG_13, 0x00 }, + { LP8860_EEPROM_REG_14, 0x00 }, + { LP8860_EEPROM_REG_15, 0x00 }, + { LP8860_EEPROM_REG_16, 0x00 }, + { LP8860_EEPROM_REG_17, 0x00 }, + { LP8860_EEPROM_REG_18, 0x00 }, + { LP8860_EEPROM_REG_19, 0x00 }, + { LP8860_EEPROM_REG_20, 0x00 }, + { LP8860_EEPROM_REG_21, 0x00 }, + { LP8860_EEPROM_REG_22, 0x00 }, + { LP8860_EEPROM_REG_23, 0x00 }, + { LP8860_EEPROM_REG_24, 0x00 }, +}; + +static const struct regmap_config lp8860_eeprom_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + + .max_register = LP8860_EEPROM_REG_24, + .reg_defaults = lp8860_eeprom_defs, + .num_reg_defaults = ARRAY_SIZE(lp8860_eeprom_defs), + .cache_type = REGCACHE_NONE, +}; + +static int lp8860_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int ret; + struct lp8860_led *led; + struct device_node *np = client->dev.of_node; + + led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL); + if (!led) + return -ENOMEM; + + led->label = LP8860_DISP_LED_NAME; + + if (client->dev.of_node) { + ret = of_property_read_string(np, "label", &led->label); + if (ret) { + dev_err(&client->dev, "Missing label in dt\n"); + return -EINVAL; + } + } + + led->enable_gpio = devm_gpiod_get_optional(&client->dev, + "enable", GPIOD_OUT_LOW); + if (IS_ERR(led->enable_gpio)) { + ret = PTR_ERR(led->enable_gpio); + dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret); + return ret; + } + + led->regulator = devm_regulator_get(&client->dev, "vled"); + if (IS_ERR(led->regulator)) + led->regulator = NULL; + + led->client = client; + led->led_dev.name = led->label; + led->led_dev.max_brightness = LED_FULL; + led->led_dev.brightness_set = lp8860_brightness_set; + + mutex_init(&led->lock); + INIT_WORK(&led->work, lp8860_led_brightness_work); + + i2c_set_clientdata(client, led); + + led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config); + if (IS_ERR(led->regmap)) { + ret = PTR_ERR(led->regmap); + dev_err(&client->dev, "Failed to allocate register map: %d\n", + ret); + return ret; + } + + led->eeprom_regmap = devm_regmap_init_i2c(client, &lp8860_eeprom_regmap_config); + if (IS_ERR(led->eeprom_regmap)) { + ret = PTR_ERR(led->eeprom_regmap); + dev_err(&client->dev, "Failed to allocate register map: %d\n", + ret); + return ret; + } + + ret = lp8860_init(led); + if (ret) + return ret; + + ret = led_classdev_register(&client->dev, &led->led_dev); + if (ret) { + dev_err(&client->dev, "led register err: %d\n", ret); + return ret; + } + + return 0; +} + +static int lp8860_remove(struct i2c_client *client) +{ + struct lp8860_led *led = i2c_get_clientdata(client); + int ret; + + led_classdev_unregister(&led->led_dev); + cancel_work_sync(&led->work); + + if (led->enable_gpio) + gpiod_direction_output(led->enable_gpio, 0); + + if (led->regulator) { + ret = regulator_disable(led->regulator); + if (ret) + dev_err(&led->client->dev, + "Failed to disable regulator\n"); + } + + return 0; +} + +static const struct i2c_device_id lp8860_id[] = { + { "lp8860", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, lp8860_id); + +#ifdef CONFIG_OF +static const struct of_device_id of_lp8860_leds_match[] = { + { .compatible = "ti,lp8860", }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_lp8860_leds_match); +#endif + +static struct i2c_driver lp8860_driver = { + .driver = { + .name = "lp8860", + .of_match_table = of_match_ptr(of_lp8860_leds_match), + }, + .probe = lp8860_probe, + .remove = lp8860_remove, + .id_table = lp8860_id, +}; +module_i2c_driver(lp8860_driver); + +MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver"); +MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>"); +MODULE_LICENSE("GPL"); |