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@@ -0,0 +1,487 @@
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+// SPDX-License-Identifier: GPL-2.0
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+// Flash and torch driver for Texas Instruments LM3601X LED
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+// Flash driver chip family
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+// Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
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+
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+#include <linux/delay.h>
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+#include <linux/i2c.h>
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+#include <linux/leds.h>
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+#include <linux/led-class-flash.h>
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+#include <linux/module.h>
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+#include <linux/regmap.h>
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+#include <linux/slab.h>
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+#include <uapi/linux/uleds.h>
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+
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+#define LM3601X_LED_IR 0x0
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+#define LM3601X_LED_TORCH 0x1
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+
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+/* Registers */
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+#define LM3601X_ENABLE_REG 0x01
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+#define LM3601X_CFG_REG 0x02
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+#define LM3601X_LED_FLASH_REG 0x03
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+#define LM3601X_LED_TORCH_REG 0x04
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+#define LM3601X_FLAGS_REG 0x05
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+#define LM3601X_DEV_ID_REG 0x06
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+
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+#define LM3601X_SW_RESET BIT(7)
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+
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+/* Enable Mode bits */
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+#define LM3601X_MODE_STANDBY 0x00
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+#define LM3601X_MODE_IR_DRV BIT(0)
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+#define LM3601X_MODE_TORCH BIT(1)
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+#define LM3601X_MODE_STROBE (BIT(0) | BIT(1))
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+#define LM3601X_STRB_EN BIT(2)
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+#define LM3601X_STRB_EDGE_TRIG BIT(3)
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+#define LM3601X_IVFM_EN BIT(4)
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+
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+#define LM36010_BOOST_LIMIT_28 BIT(5)
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+#define LM36010_BOOST_FREQ_4MHZ BIT(6)
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+#define LM36010_BOOST_MODE_PASS BIT(7)
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+
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+/* Flag Mask */
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+#define LM3601X_FLASH_TIME_OUT BIT(0)
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+#define LM3601X_UVLO_FAULT BIT(1)
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+#define LM3601X_THERM_SHUTDOWN BIT(2)
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+#define LM3601X_THERM_CURR BIT(3)
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+#define LM36010_CURR_LIMIT BIT(4)
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+#define LM3601X_SHORT_FAULT BIT(5)
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+#define LM3601X_IVFM_TRIP BIT(6)
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+#define LM36010_OVP_FAULT BIT(7)
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+
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+#define LM3601X_MAX_TORCH_I_UA 376000
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+#define LM3601X_MIN_TORCH_I_UA 2400
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+#define LM3601X_TORCH_REG_DIV 2965
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+
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+#define LM3601X_MAX_STROBE_I_UA 1500000
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+#define LM3601X_MIN_STROBE_I_UA 11000
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+#define LM3601X_STROBE_REG_DIV 11800
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+
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+#define LM3601X_TIMEOUT_MASK 0x1e
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+#define LM3601X_ENABLE_MASK (LM3601X_MODE_IR_DRV | LM3601X_MODE_TORCH)
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+
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+#define LM3601X_LOWER_STEP_US 40000
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+#define LM3601X_UPPER_STEP_US 200000
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+#define LM3601X_MIN_TIMEOUT_US 40000
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+#define LM3601X_MAX_TIMEOUT_US 1600000
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+#define LM3601X_TIMEOUT_XOVER_US 400000
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+
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+enum lm3601x_type {
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+ CHIP_LM36010 = 0,
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+ CHIP_LM36011,
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+};
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+
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+/**
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+ * struct lm3601x_led -
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+ * @fled_cdev: flash LED class device pointer
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+ * @client: Pointer to the I2C client
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+ * @regmap: Devices register map
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+ * @lock: Lock for reading/writing the device
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+ * @led_name: LED label for the Torch or IR LED
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+ * @flash_timeout: the timeout for the flash
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+ * @last_flag: last known flags register value
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+ * @torch_current_max: maximum current for the torch
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+ * @flash_current_max: maximum current for the flash
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+ * @max_flash_timeout: maximum timeout for the flash
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+ * @led_mode: The mode to enable either IR or Torch
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+ */
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+struct lm3601x_led {
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+ struct led_classdev_flash fled_cdev;
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+ struct i2c_client *client;
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+ struct regmap *regmap;
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+ struct mutex lock;
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+
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+ char led_name[LED_MAX_NAME_SIZE];
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+
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+ unsigned int flash_timeout;
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+ unsigned int last_flag;
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+
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+ u32 torch_current_max;
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+ u32 flash_current_max;
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+ u32 max_flash_timeout;
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+
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+ u32 led_mode;
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+};
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+
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+static const struct reg_default lm3601x_regmap_defs[] = {
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+ { LM3601X_ENABLE_REG, 0x20 },
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+ { LM3601X_CFG_REG, 0x15 },
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+ { LM3601X_LED_FLASH_REG, 0x00 },
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+ { LM3601X_LED_TORCH_REG, 0x00 },
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+};
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+
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+static bool lm3601x_volatile_reg(struct device *dev, unsigned int reg)
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+{
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+ switch (reg) {
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+ case LM3601X_FLAGS_REG:
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+ return true;
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+ default:
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+ return false;
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+ }
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+}
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+
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+static const struct regmap_config lm3601x_regmap = {
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+ .reg_bits = 8,
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+ .val_bits = 8,
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+
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+ .max_register = LM3601X_DEV_ID_REG,
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+ .reg_defaults = lm3601x_regmap_defs,
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+ .num_reg_defaults = ARRAY_SIZE(lm3601x_regmap_defs),
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+ .cache_type = REGCACHE_RBTREE,
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+ .volatile_reg = lm3601x_volatile_reg,
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+};
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+
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+static struct lm3601x_led *fled_cdev_to_led(struct led_classdev_flash *fled_cdev)
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+{
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+ return container_of(fled_cdev, struct lm3601x_led, fled_cdev);
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+}
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+
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+static int lm3601x_read_faults(struct lm3601x_led *led)
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+{
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+ int flags_val;
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+ int ret;
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+
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+ ret = regmap_read(led->regmap, LM3601X_FLAGS_REG, &flags_val);
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+ if (ret < 0)
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+ return -EIO;
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+
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+ led->last_flag = 0;
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+
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+ if (flags_val & LM36010_OVP_FAULT)
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+ led->last_flag |= LED_FAULT_OVER_VOLTAGE;
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+
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+ if (flags_val & (LM3601X_THERM_SHUTDOWN | LM3601X_THERM_CURR))
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+ led->last_flag |= LED_FAULT_OVER_TEMPERATURE;
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+
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+ if (flags_val & LM3601X_SHORT_FAULT)
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+ led->last_flag |= LED_FAULT_SHORT_CIRCUIT;
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+
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+ if (flags_val & LM36010_CURR_LIMIT)
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+ led->last_flag |= LED_FAULT_OVER_CURRENT;
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+
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+ if (flags_val & LM3601X_UVLO_FAULT)
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+ led->last_flag |= LED_FAULT_UNDER_VOLTAGE;
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+
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+ if (flags_val & LM3601X_IVFM_TRIP)
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+ led->last_flag |= LED_FAULT_INPUT_VOLTAGE;
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+
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+ if (flags_val & LM3601X_THERM_SHUTDOWN)
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+ led->last_flag |= LED_FAULT_LED_OVER_TEMPERATURE;
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+
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+ return led->last_flag;
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+}
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+
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+static int lm3601x_brightness_set(struct led_classdev *cdev,
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+ enum led_brightness brightness)
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+{
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+ struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(cdev);
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+ struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
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+ int ret, led_mode_val;
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+
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+ mutex_lock(&led->lock);
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+
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+ ret = lm3601x_read_faults(led);
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+ if (ret < 0)
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+ goto out;
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+
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+ if (led->led_mode == LM3601X_LED_TORCH)
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+ led_mode_val = LM3601X_MODE_TORCH;
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+ else
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+ led_mode_val = LM3601X_MODE_IR_DRV;
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+
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+ if (brightness == LED_OFF) {
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+ ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
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+ led_mode_val, LED_OFF);
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+ goto out;
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+ }
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+
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+ ret = regmap_write(led->regmap, LM3601X_LED_TORCH_REG, brightness);
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+ if (ret < 0)
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+ goto out;
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+
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+ ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
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+ LM3601X_MODE_TORCH | LM3601X_MODE_IR_DRV,
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+ led_mode_val);
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+out:
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+ mutex_unlock(&led->lock);
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+ return ret;
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+}
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+
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+static int lm3601x_strobe_set(struct led_classdev_flash *fled_cdev,
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+ bool state)
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+{
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+ struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
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+ int timeout_reg_val;
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+ int current_timeout;
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+ int ret;
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+
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+ mutex_lock(&led->lock);
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+
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+ ret = regmap_read(led->regmap, LM3601X_CFG_REG, ¤t_timeout);
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+ if (ret < 0)
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+ goto out;
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+
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+ if (led->flash_timeout >= LM3601X_TIMEOUT_XOVER_US)
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+ timeout_reg_val = led->flash_timeout / LM3601X_UPPER_STEP_US + 0x07;
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+ else
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+ timeout_reg_val = led->flash_timeout / LM3601X_LOWER_STEP_US - 0x01;
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+
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+ if (led->flash_timeout != current_timeout)
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+ ret = regmap_update_bits(led->regmap, LM3601X_CFG_REG,
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+ LM3601X_TIMEOUT_MASK, timeout_reg_val);
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+
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+ if (state)
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+ ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
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+ LM3601X_MODE_TORCH | LM3601X_MODE_IR_DRV,
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+ LM3601X_MODE_STROBE);
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+ else
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+ ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
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+ LM3601X_MODE_STROBE, LED_OFF);
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+
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+ ret = lm3601x_read_faults(led);
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+out:
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+ mutex_unlock(&led->lock);
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+ return ret;
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+}
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+
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+static int lm3601x_flash_brightness_set(struct led_classdev_flash *fled_cdev,
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+ u32 brightness)
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+{
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+ struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
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+ u8 brightness_val;
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+ int ret;
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+
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+ mutex_lock(&led->lock);
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+ ret = lm3601x_read_faults(led);
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+ if (ret < 0)
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+ goto out;
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+
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+ if (brightness == LED_OFF) {
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+ ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
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+ LM3601X_MODE_STROBE, LED_OFF);
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+ goto out;
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+ }
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+
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+ brightness_val = brightness / LM3601X_STROBE_REG_DIV;
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+
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+ ret = regmap_write(led->regmap, LM3601X_LED_FLASH_REG, brightness_val);
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+out:
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+ mutex_unlock(&led->lock);
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+ return ret;
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+}
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+
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+static int lm3601x_flash_timeout_set(struct led_classdev_flash *fled_cdev,
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+ u32 timeout)
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+{
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+ struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
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+
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+ mutex_lock(&led->lock);
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+
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+ led->flash_timeout = timeout;
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+
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+ mutex_unlock(&led->lock);
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+
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+ return 0;
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+}
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+
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+static int lm3601x_strobe_get(struct led_classdev_flash *fled_cdev, bool *state)
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+{
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+ struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
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+ int strobe_state;
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+ int ret;
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+
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+ mutex_lock(&led->lock);
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+
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+ ret = regmap_read(led->regmap, LM3601X_ENABLE_REG, &strobe_state);
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+ if (ret < 0)
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+ goto out;
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+
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+ *state = strobe_state & LM3601X_MODE_STROBE;
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+
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+out:
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+ mutex_unlock(&led->lock);
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+ return ret;
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+}
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+
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+static int lm3601x_flash_fault_get(struct led_classdev_flash *fled_cdev,
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+ u32 *fault)
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+{
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+ struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
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+
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+ lm3601x_read_faults(led);
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+
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+ *fault = led->last_flag;
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+
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+ return 0;
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+}
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+
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+static const struct led_flash_ops flash_ops = {
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+ .flash_brightness_set = lm3601x_flash_brightness_set,
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+ .strobe_set = lm3601x_strobe_set,
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+ .strobe_get = lm3601x_strobe_get,
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+ .timeout_set = lm3601x_flash_timeout_set,
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+ .fault_get = lm3601x_flash_fault_get,
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+};
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+
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+static int lm3601x_register_leds(struct lm3601x_led *led)
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+{
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+ struct led_classdev *led_cdev;
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+ struct led_flash_setting *setting;
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+
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+ led->fled_cdev.ops = &flash_ops;
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+
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+ setting = &led->fled_cdev.timeout;
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+ setting->min = LM3601X_MIN_TIMEOUT_US;
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+ setting->max = led->max_flash_timeout;
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+ setting->step = LM3601X_LOWER_STEP_US;
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+ setting->val = led->max_flash_timeout;
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+
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+ setting = &led->fled_cdev.brightness;
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+ setting->min = LM3601X_MIN_STROBE_I_UA;
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+ setting->max = led->flash_current_max;
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+ setting->step = LM3601X_TORCH_REG_DIV;
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+ setting->val = led->flash_current_max;
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+
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+ led_cdev = &led->fled_cdev.led_cdev;
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+ led_cdev->name = led->led_name;
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+ led_cdev->brightness_set_blocking = lm3601x_brightness_set;
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+ led_cdev->max_brightness = DIV_ROUND_UP(led->torch_current_max,
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+ LM3601X_TORCH_REG_DIV);
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+ led_cdev->flags |= LED_DEV_CAP_FLASH;
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+
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+ return led_classdev_flash_register(&led->client->dev, &led->fled_cdev);
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+}
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+
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+static int lm3601x_parse_node(struct lm3601x_led *led)
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+{
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+ struct fwnode_handle *child = NULL;
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+ int ret = -ENODEV;
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+ const char *name;
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+
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+ child = device_get_next_child_node(&led->client->dev, child);
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+ if (!child) {
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+ dev_err(&led->client->dev, "No LED Child node\n");
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+ return ret;
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+ }
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+
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+ ret = fwnode_property_read_u32(child, "reg", &led->led_mode);
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+ if (ret) {
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+ dev_err(&led->client->dev, "reg DT property missing\n");
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+ goto out_err;
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+ }
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+
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+ if (led->led_mode > LM3601X_LED_TORCH ||
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+ led->led_mode < LM3601X_LED_IR) {
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+ dev_warn(&led->client->dev, "Invalid led mode requested\n");
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+ ret = -EINVAL;
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+ goto out_err;
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+ }
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+
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+ ret = fwnode_property_read_string(child, "label", &name);
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+ if (ret) {
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+ if (led->led_mode == LM3601X_LED_TORCH)
|
|
|
+ name = "torch";
|
|
|
+ else
|
|
|
+ name = "infrared";
|
|
|
+ }
|
|
|
+
|
|
|
+ snprintf(led->led_name, sizeof(led->led_name),
|
|
|
+ "%s:%s", led->client->name, name);
|
|
|
+
|
|
|
+ ret = fwnode_property_read_u32(child, "led-max-microamp",
|
|
|
+ &led->torch_current_max);
|
|
|
+ if (ret) {
|
|
|
+ dev_warn(&led->client->dev,
|
|
|
+ "led-max-microamp DT property missing\n");
|
|
|
+ goto out_err;
|
|
|
+ }
|
|
|
+
|
|
|
+ ret = fwnode_property_read_u32(child, "flash-max-microamp",
|
|
|
+ &led->flash_current_max);
|
|
|
+ if (ret) {
|
|
|
+ dev_warn(&led->client->dev,
|
|
|
+ "flash-max-microamp DT property missing\n");
|
|
|
+ goto out_err;
|
|
|
+ }
|
|
|
+
|
|
|
+ ret = fwnode_property_read_u32(child, "flash-max-timeout-us",
|
|
|
+ &led->max_flash_timeout);
|
|
|
+ if (ret) {
|
|
|
+ dev_warn(&led->client->dev,
|
|
|
+ "flash-max-timeout-us DT property missing\n");
|
|
|
+ goto out_err;
|
|
|
+ }
|
|
|
+
|
|
|
+out_err:
|
|
|
+ fwnode_handle_put(child);
|
|
|
+ return ret;
|
|
|
+}
|
|
|
+
|
|
|
+static int lm3601x_probe(struct i2c_client *client)
|
|
|
+{
|
|
|
+ struct lm3601x_led *led;
|
|
|
+ int ret;
|
|
|
+
|
|
|
+ led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
|
|
|
+ if (!led)
|
|
|
+ return -ENOMEM;
|
|
|
+
|
|
|
+ led->client = client;
|
|
|
+ i2c_set_clientdata(client, led);
|
|
|
+
|
|
|
+ ret = lm3601x_parse_node(led);
|
|
|
+ if (ret)
|
|
|
+ return -ENODEV;
|
|
|
+
|
|
|
+ led->regmap = devm_regmap_init_i2c(client, &lm3601x_regmap);
|
|
|
+ if (IS_ERR(led->regmap)) {
|
|
|
+ ret = PTR_ERR(led->regmap);
|
|
|
+ dev_err(&client->dev,
|
|
|
+ "Failed to allocate register map: %d\n", ret);
|
|
|
+ return ret;
|
|
|
+ }
|
|
|
+
|
|
|
+ mutex_init(&led->lock);
|
|
|
+
|
|
|
+ return lm3601x_register_leds(led);
|
|
|
+}
|
|
|
+
|
|
|
+static int lm3601x_remove(struct i2c_client *client)
|
|
|
+{
|
|
|
+ struct lm3601x_led *led = i2c_get_clientdata(client);
|
|
|
+
|
|
|
+ led_classdev_flash_unregister(&led->fled_cdev);
|
|
|
+ mutex_destroy(&led->lock);
|
|
|
+
|
|
|
+ return regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
|
|
|
+ LM3601X_ENABLE_MASK,
|
|
|
+ LM3601X_MODE_STANDBY);
|
|
|
+}
|
|
|
+
|
|
|
+static const struct i2c_device_id lm3601x_id[] = {
|
|
|
+ { "LM36010", CHIP_LM36010 },
|
|
|
+ { "LM36011", CHIP_LM36011 },
|
|
|
+ { }
|
|
|
+};
|
|
|
+MODULE_DEVICE_TABLE(i2c, lm3601x_id);
|
|
|
+
|
|
|
+static const struct of_device_id of_lm3601x_leds_match[] = {
|
|
|
+ { .compatible = "ti,lm36010", },
|
|
|
+ { .compatible = "ti,lm36011", },
|
|
|
+ { }
|
|
|
+};
|
|
|
+MODULE_DEVICE_TABLE(of, of_lm3601x_leds_match);
|
|
|
+
|
|
|
+static struct i2c_driver lm3601x_i2c_driver = {
|
|
|
+ .driver = {
|
|
|
+ .name = "lm3601x",
|
|
|
+ .of_match_table = of_lm3601x_leds_match,
|
|
|
+ },
|
|
|
+ .probe_new = lm3601x_probe,
|
|
|
+ .remove = lm3601x_remove,
|
|
|
+ .id_table = lm3601x_id,
|
|
|
+};
|
|
|
+module_i2c_driver(lm3601x_i2c_driver);
|
|
|
+
|
|
|
+MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3601X");
|
|
|
+MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
|
|
|
+MODULE_LICENSE("GPL v2");
|
Linus Torvalds