293 lines
		
	
	
		
			6.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			293 lines
		
	
	
		
			6.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *	LED driver for TI lp3952 controller
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|  *
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|  *	Copyright (C) 2016, DAQRI, LLC.
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|  *	Author: Tony Makkiel <tony.makkiel@daqri.com>
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  *
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|  */
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| 
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| #include <linux/delay.h>
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| #include <linux/gpio.h>
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| #include <linux/i2c.h>
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| #include <linux/io.h>
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| #include <linux/kernel.h>
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| #include <linux/leds.h>
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| #include <linux/leds-lp3952.h>
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| #include <linux/module.h>
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| #include <linux/notifier.h>
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| #include <linux/platform_device.h>
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| #include <linux/pm.h>
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| #include <linux/reboot.h>
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| #include <linux/regmap.h>
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| 
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| static int lp3952_register_write(struct i2c_client *client, u8 reg, u8 val)
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| {
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| 	int ret;
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| 	struct lp3952_led_array *priv = i2c_get_clientdata(client);
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| 
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| 	ret = regmap_write(priv->regmap, reg, val);
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| 
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| 	if (ret)
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| 		dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
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| 			__func__, reg, val, ret);
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| 	return ret;
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| }
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| 
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| static void lp3952_on_off(struct lp3952_led_array *priv,
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| 			  enum lp3952_leds led_id, bool on)
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| {
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| 	int ret, val;
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| 
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| 	dev_dbg(&priv->client->dev, "%s LED %d to %d\n", __func__, led_id, on);
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| 
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| 	val = 1 << led_id;
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| 	if (led_id == LP3952_LED_ALL)
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| 		val = LP3952_LED_MASK_ALL;
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| 
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| 	ret = regmap_update_bits(priv->regmap, LP3952_REG_LED_CTRL, val,
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| 				 on ? val : 0);
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| 	if (ret)
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| 		dev_err(&priv->client->dev, "%s, Error %d\n", __func__, ret);
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| }
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| 
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| /*
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|  * Using Imax to control brightness. There are 4 possible
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|  * setting 25, 50, 75 and 100 % of Imax. Possible values are
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|  * values 0-4. 0 meaning turn off.
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|  */
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| static int lp3952_set_brightness(struct led_classdev *cdev,
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| 				 enum led_brightness value)
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| {
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| 	unsigned int reg, shift_val;
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| 	struct lp3952_ctrl_hdl *led = container_of(cdev,
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| 						   struct lp3952_ctrl_hdl,
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| 						   cdev);
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| 	struct lp3952_led_array *priv = (struct lp3952_led_array *)led->priv;
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| 
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| 	dev_dbg(cdev->dev, "Brightness request: %d on %d\n", value,
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| 		led->channel);
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| 
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| 	if (value == LED_OFF) {
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| 		lp3952_on_off(priv, led->channel, false);
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| 		return 0;
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| 	}
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| 
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| 	if (led->channel > LP3952_RED_1) {
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| 		dev_err(cdev->dev, " %s Invalid LED requested", __func__);
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| 		return -EINVAL;
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| 	}
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| 
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| 	if (led->channel >= LP3952_BLUE_1) {
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| 		reg = LP3952_REG_RGB1_MAX_I_CTRL;
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| 		shift_val = (led->channel - LP3952_BLUE_1) * 2;
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| 	} else {
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| 		reg = LP3952_REG_RGB2_MAX_I_CTRL;
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| 		shift_val = led->channel * 2;
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| 	}
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| 
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| 	/* Enable the LED in case it is not enabled already */
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| 	lp3952_on_off(priv, led->channel, true);
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| 
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| 	return regmap_update_bits(priv->regmap, reg, 3 << shift_val,
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| 				  --value << shift_val);
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| }
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| 
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| static int lp3952_get_label(struct device *dev, const char *label, char *dest)
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| {
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| 	int ret;
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| 	const char *str;
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| 
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| 	ret = device_property_read_string(dev, label, &str);
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| 	if (ret)
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| 		return ret;
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| 
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| 	strncpy(dest, str, LP3952_LABEL_MAX_LEN);
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| 	return 0;
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| }
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| 
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| static int lp3952_register_led_classdev(struct lp3952_led_array *priv)
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| {
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| 	int i, acpi_ret, ret = -ENODEV;
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| 	static const char *led_name_hdl[LP3952_LED_ALL] = {
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| 		"blue2",
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| 		"green2",
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| 		"red2",
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| 		"blue1",
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| 		"green1",
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| 		"red1"
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| 	};
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| 
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| 	for (i = 0; i < LP3952_LED_ALL; i++) {
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| 		acpi_ret = lp3952_get_label(&priv->client->dev, led_name_hdl[i],
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| 					    priv->leds[i].name);
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| 		if (acpi_ret)
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| 			continue;
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| 
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| 		priv->leds[i].cdev.name = priv->leds[i].name;
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| 		priv->leds[i].cdev.brightness = LED_OFF;
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| 		priv->leds[i].cdev.max_brightness = LP3952_BRIGHT_MAX;
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| 		priv->leds[i].cdev.brightness_set_blocking =
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| 				lp3952_set_brightness;
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| 		priv->leds[i].channel = i;
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| 		priv->leds[i].priv = priv;
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| 
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| 		ret = devm_led_classdev_register(&priv->client->dev,
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| 						 &priv->leds[i].cdev);
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| 		if (ret < 0) {
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| 			dev_err(&priv->client->dev,
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| 				"couldn't register LED %s\n",
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| 				priv->leds[i].cdev.name);
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| 			break;
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| 		}
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| 	}
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| 	return ret;
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| }
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| 
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| static int lp3952_set_pattern_gen_cmd(struct lp3952_led_array *priv,
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| 				      u8 cmd_index, u8 r, u8 g, u8 b,
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| 				      enum lp3952_tt tt, enum lp3952_cet cet)
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| {
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| 	int ret;
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| 	struct ptrn_gen_cmd line = {
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| 		{
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| 			{
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| 				.r = r,
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| 				.g = g,
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| 				.b = b,
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| 				.cet = cet,
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| 				.tt = tt
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| 			}
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| 		}
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| 	};
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| 
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| 	if (cmd_index >= LP3952_CMD_REG_COUNT)
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| 		return -EINVAL;
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| 
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| 	ret = lp3952_register_write(priv->client,
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| 				    LP3952_REG_CMD_0 + cmd_index * 2,
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| 				    line.bytes.msb);
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| 	if (ret)
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| 		return ret;
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| 
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| 	return lp3952_register_write(priv->client,
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| 				      LP3952_REG_CMD_0 + cmd_index * 2 + 1,
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| 				      line.bytes.lsb);
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| }
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| 
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| static int lp3952_configure(struct lp3952_led_array *priv)
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| {
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| 	int ret;
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| 
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| 	/* Disable any LEDs on from any previous conf. */
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| 	ret = lp3952_register_write(priv->client, LP3952_REG_LED_CTRL, 0);
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| 	if (ret)
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| 		return ret;
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| 
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| 	/* enable rgb patter, loop */
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| 	ret = lp3952_register_write(priv->client, LP3952_REG_PAT_GEN_CTRL,
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| 				    LP3952_PATRN_LOOP | LP3952_PATRN_GEN_EN);
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| 	if (ret)
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| 		return ret;
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| 
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| 	/* Update Bit 6 (Active mode), Select both Led sets, Bit [1:0] */
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| 	ret = lp3952_register_write(priv->client, LP3952_REG_ENABLES,
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| 				    LP3952_ACTIVE_MODE | LP3952_INT_B00ST_LDR);
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| 	if (ret)
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| 		return ret;
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| 
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| 	/* Set Cmd1 for RGB intensity,cmd and transition time */
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| 	return lp3952_set_pattern_gen_cmd(priv, 0, I46, I71, I100, TT0,
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| 					   CET197);
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| }
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| 
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| static const struct regmap_config lp3952_regmap = {
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| 	.reg_bits = 8,
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| 	.val_bits = 8,
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| 	.max_register = REG_MAX,
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| 	.cache_type = REGCACHE_RBTREE,
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| };
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| 
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| static int lp3952_probe(struct i2c_client *client,
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| 			const struct i2c_device_id *id)
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| {
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| 	int status;
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| 	struct lp3952_led_array *priv;
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| 
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| 	priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
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| 	if (!priv)
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| 		return -ENOMEM;
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| 
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| 	priv->client = client;
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| 
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| 	priv->enable_gpio = devm_gpiod_get(&client->dev, "nrst",
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| 					   GPIOD_OUT_HIGH);
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| 	if (IS_ERR(priv->enable_gpio)) {
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| 		status = PTR_ERR(priv->enable_gpio);
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| 		dev_err(&client->dev, "Failed to enable gpio: %d\n", status);
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| 		return status;
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| 	}
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| 
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| 	priv->regmap = devm_regmap_init_i2c(client, &lp3952_regmap);
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| 	if (IS_ERR(priv->regmap)) {
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| 		int err = PTR_ERR(priv->regmap);
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| 
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| 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
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| 			err);
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| 		return err;
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| 	}
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| 
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| 	i2c_set_clientdata(client, priv);
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| 
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| 	status = lp3952_configure(priv);
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| 	if (status) {
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| 		dev_err(&client->dev, "Probe failed. Device not found (%d)\n",
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| 			status);
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| 		return status;
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| 	}
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| 
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| 	status = lp3952_register_led_classdev(priv);
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| 	if (status) {
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| 		dev_err(&client->dev, "Unable to register led_classdev: %d\n",
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| 			status);
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| 		return status;
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| 	}
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| 
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| 	return 0;
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| }
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| 
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| static int lp3952_remove(struct i2c_client *client)
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| {
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| 	struct lp3952_led_array *priv;
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| 
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| 	priv = i2c_get_clientdata(client);
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| 	lp3952_on_off(priv, LP3952_LED_ALL, false);
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| 	gpiod_set_value(priv->enable_gpio, 0);
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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 i2c_device_id lp3952_id[] = {
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| 	{LP3952_NAME, 0},
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| 	{}
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| };
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| MODULE_DEVICE_TABLE(i2c, lp3952_id);
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| 
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| static struct i2c_driver lp3952_i2c_driver = {
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| 	.driver = {
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| 			.name = LP3952_NAME,
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| 	},
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| 	.probe = lp3952_probe,
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| 	.remove = lp3952_remove,
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| 	.id_table = lp3952_id,
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| };
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| 
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| module_i2c_driver(lp3952_i2c_driver);
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| 
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| MODULE_AUTHOR("Tony Makkiel <tony.makkiel@daqri.com>");
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| MODULE_DESCRIPTION("lp3952 I2C LED controller driver");
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| MODULE_LICENSE("GPL v2");
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