leds: lp8860: Introduce TI lp8860 4 channel LED driver
[firefly-linux-kernel-4.4.55.git] / drivers / leds / leds-lp8860.c
diff --git a/drivers/leds/leds-lp8860.c b/drivers/leds/leds-lp8860.c
new file mode 100644 (file)
index 0000000..840e93f
--- /dev/null
@@ -0,0 +1,491 @@
+/*
+ * 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(&client->dev, "enable");
+       if (IS_ERR(led->enable_gpio))
+               led->enable_gpio = NULL;
+       else
+               gpiod_direction_output(led->enable_gpio, 0);
+
+       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 drvier");
+MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
+MODULE_LICENSE("GPL");