[deliverable/linux.git] / drivers / video / backlight / lv5207lp.c

/*
 * Sanyo LV5207LP LED Driver
 *
 * Copyright (C) 2013 Ideas on board SPRL
 *
 * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.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/backlight.h>
#include <linux/err.h>
#include <linux/fb.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/platform_data/lv5207lp.h>
#include <linux/slab.h>

#define LV5207LP_CTRL1			0x00
#define LV5207LP_CPSW			(1 << 7)
#define LV5207LP_SCTEN			(1 << 6)
#define LV5207LP_C10			(1 << 5)
#define LV5207LP_CKSW			(1 << 4)
#define LV5207LP_RSW			(1 << 3)
#define LV5207LP_GSW			(1 << 2)
#define LV5207LP_BSW			(1 << 1)
#define LV5207LP_CTRL2			0x01
#define LV5207LP_MSW			(1 << 7)
#define LV5207LP_MLED4			(1 << 6)
#define LV5207LP_RED			0x02
#define LV5207LP_GREEN			0x03
#define LV5207LP_BLUE			0x04

#define LV5207LP_MAX_BRIGHTNESS		32

struct lv5207lp {
	struct i2c_client *client;
	struct backlight_device *backlight;
	struct lv5207lp_platform_data *pdata;
};

static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data)
{
	return i2c_smbus_write_byte_data(lv->client, reg, data);
}

static int lv5207lp_backlight_update_status(struct backlight_device *backlight)
{
	struct lv5207lp *lv = bl_get_data(backlight);
	int brightness = backlight->props.brightness;

	if (backlight->props.power != FB_BLANK_UNBLANK ||
	    backlight->props.fb_blank != FB_BLANK_UNBLANK ||
	    backlight->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
		brightness = 0;

	if (brightness) {
		lv5207lp_write(lv, LV5207LP_CTRL1,
			       LV5207LP_CPSW | LV5207LP_C10 | LV5207LP_CKSW);
		lv5207lp_write(lv, LV5207LP_CTRL2,
			       LV5207LP_MSW | LV5207LP_MLED4 |
			       (brightness - 1));
	} else {
		lv5207lp_write(lv, LV5207LP_CTRL1, 0);
		lv5207lp_write(lv, LV5207LP_CTRL2, 0);
	}

	return 0;
}

static int lv5207lp_backlight_get_brightness(struct backlight_device *backlight)
{
	return backlight->props.brightness;
}

static int lv5207lp_backlight_check_fb(struct backlight_device *backlight,
				       struct fb_info *info)
{
	struct lv5207lp *lv = bl_get_data(backlight);

	return lv->pdata->fbdev == NULL || lv->pdata->fbdev == info->dev;
}

static const struct backlight_ops lv5207lp_backlight_ops = {
	.options	= BL_CORE_SUSPENDRESUME,
	.update_status	= lv5207lp_backlight_update_status,
	.get_brightness	= lv5207lp_backlight_get_brightness,
	.check_fb	= lv5207lp_backlight_check_fb,
};

static int lv5207lp_probe(struct i2c_client *client,
			  const struct i2c_device_id *id)
{
	struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev);
	struct backlight_device *backlight;
	struct backlight_properties props;
	struct lv5207lp *lv;

	if (pdata == NULL) {
		dev_err(&client->dev, "No platform data supplied\n");
		return -EINVAL;
	}

	if (!i2c_check_functionality(client->adapter,
				     I2C_FUNC_SMBUS_BYTE_DATA)) {
		dev_warn(&client->dev,
			 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
		return -EIO;
	}

	lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL);
	if (!lv)
		return -ENOMEM;

	lv->client = client;
	lv->pdata = pdata;

	memset(&props, 0, sizeof(props));
	props.type = BACKLIGHT_RAW;
	props.max_brightness = min_t(unsigned int, pdata->max_value,
				     LV5207LP_MAX_BRIGHTNESS);
	props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
				   props.max_brightness);

	backlight = backlight_device_register(dev_name(&client->dev),
					      &lv->client->dev, lv,
					      &lv5207lp_backlight_ops, &props);
	if (IS_ERR(backlight)) {
		dev_err(&client->dev, "failed to register backlight\n");
		return PTR_ERR(backlight);
	}

	backlight_update_status(backlight);
	i2c_set_clientdata(client, backlight);

	return 0;
}

static int lv5207lp_remove(struct i2c_client *client)
{
	struct backlight_device *backlight = i2c_get_clientdata(client);

	backlight->props.brightness = 0;
	backlight_update_status(backlight);
	backlight_device_unregister(backlight);

	return 0;
}

static const struct i2c_device_id lv5207lp_ids[] = {
	{ "lv5207lp", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, lv5207lp_ids);

static struct i2c_driver lv5207lp_driver = {
	.driver = {
		.name = "lv5207lp",
	},
	.probe = lv5207lp_probe,
	.remove = lv5207lp_remove,
	.id_table = lv5207lp_ids,
};

module_i2c_driver(lv5207lp_driver);

MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver");
MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
82e5c40d LP	1	/*
	2	* Sanyo LV5207LP LED Driver
	3	*
	4	* Copyright (C) 2013 Ideas on board SPRL
	5	*
	6	* Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/backlight.h>
	14	#include <linux/err.h>
	15	#include <linux/fb.h>
	16	#include <linux/i2c.h>
	17	#include <linux/module.h>
	18	#include <linux/platform_data/lv5207lp.h>
	19	#include <linux/slab.h>
	20
	21	#define LV5207LP_CTRL1 0x00
	22	#define LV5207LP_CPSW (1 << 7)
	23	#define LV5207LP_SCTEN (1 << 6)
	24	#define LV5207LP_C10 (1 << 5)
	25	#define LV5207LP_CKSW (1 << 4)
	26	#define LV5207LP_RSW (1 << 3)
	27	#define LV5207LP_GSW (1 << 2)
	28	#define LV5207LP_BSW (1 << 1)
	29	#define LV5207LP_CTRL2 0x01
	30	#define LV5207LP_MSW (1 << 7)
	31	#define LV5207LP_MLED4 (1 << 6)
	32	#define LV5207LP_RED 0x02
	33	#define LV5207LP_GREEN 0x03
	34	#define LV5207LP_BLUE 0x04
	35
	36	#define LV5207LP_MAX_BRIGHTNESS 32
	37
	38	struct lv5207lp {
	39	struct i2c_client *client;
	40	struct backlight_device *backlight;
	41	struct lv5207lp_platform_data *pdata;
	42	};
	43
	44	static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data)
	45	{
	46	return i2c_smbus_write_byte_data(lv->client, reg, data);
	47	}
	48
	49	static int lv5207lp_backlight_update_status(struct backlight_device *backlight)
	50	{
	51	struct lv5207lp *lv = bl_get_data(backlight);
	52	int brightness = backlight->props.brightness;
	53
	54	if (backlight->props.power != FB_BLANK_UNBLANK \|\|
	55	backlight->props.fb_blank != FB_BLANK_UNBLANK \|\|
	56	backlight->props.state & (BL_CORE_SUSPENDED \| BL_CORE_FBBLANK))
	57	brightness = 0;
	58
	59	if (brightness) {
	60	lv5207lp_write(lv, LV5207LP_CTRL1,
	61	LV5207LP_CPSW \| LV5207LP_C10 \| LV5207LP_CKSW);
	62	lv5207lp_write(lv, LV5207LP_CTRL2,
	63	LV5207LP_MSW \| LV5207LP_MLED4 \|
	64	(brightness - 1));
65	} else {
66	lv5207lp_write(lv, LV5207LP_CTRL1, 0);
67	lv5207lp_write(lv, LV5207LP_CTRL2, 0);
68	}
69
70	return 0;
71	}
72
73	static int lv5207lp_backlight_get_brightness(struct backlight_device *backlight)
74	{
75	return backlight->props.brightness;
76	}
77
78	static int lv5207lp_backlight_check_fb(struct backlight_device *backlight,
79	struct fb_info *info)
80	{
81	struct lv5207lp *lv = bl_get_data(backlight);
82
83	return lv->pdata->fbdev == NULL \|\| lv->pdata->fbdev == info->dev;
84	}
85
86	static const struct backlight_ops lv5207lp_backlight_ops = {
87	.options = BL_CORE_SUSPENDRESUME,
88	.update_status = lv5207lp_backlight_update_status,
89	.get_brightness = lv5207lp_backlight_get_brightness,
90	.check_fb = lv5207lp_backlight_check_fb,
91	};
92
93	static int lv5207lp_probe(struct i2c_client *client,
94	const struct i2c_device_id *id)
95	{
c512794c	96	struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev);
82e5c40d LP	97	struct backlight_device *backlight;
	98	struct backlight_properties props;
	99	struct lv5207lp *lv;
	100
	101	if (pdata == NULL) {
	102	dev_err(&client->dev, "No platform data supplied\n");
	103	return -EINVAL;
	104	}
	105
	106	if (!i2c_check_functionality(client->adapter,
	107	I2C_FUNC_SMBUS_BYTE_DATA)) {
	108	dev_warn(&client->dev,
	109	"I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
	110	return -EIO;
	111	}
	112
	113	lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL);
	114	if (!lv)
	115	return -ENOMEM;
	116
	117	lv->client = client;
	118	lv->pdata = pdata;
	119
	120	memset(&props, 0, sizeof(props));
	121	props.type = BACKLIGHT_RAW;
	122	props.max_brightness = min_t(unsigned int, pdata->max_value,
	123	LV5207LP_MAX_BRIGHTNESS);
	124	props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
	125	props.max_brightness);
	126
	127	backlight = backlight_device_register(dev_name(&client->dev),
	128	&lv->client->dev, lv,
	129	&lv5207lp_backlight_ops, &props);
	130	if (IS_ERR(backlight)) {
	131	dev_err(&client->dev, "failed to register backlight\n");
	132	return PTR_ERR(backlight);
	133	}
	134
	135	backlight_update_status(backlight);
	136	i2c_set_clientdata(client, backlight);
	137
	138	return 0;
	139	}
	140
	141	static int lv5207lp_remove(struct i2c_client *client)
	142	{
	143	struct backlight_device *backlight = i2c_get_clientdata(client);
	144
	145	backlight->props.brightness = 0;
	146	backlight_update_status(backlight);
	147	backlight_device_unregister(backlight);
	148
	149	return 0;
	150	}
	151
	152	static const struct i2c_device_id lv5207lp_ids[] = {
	153	{ "lv5207lp", 0 },
	154	{ }
	155	};
	156	MODULE_DEVICE_TABLE(i2c, lv5207lp_ids);
	157
	158	static struct i2c_driver lv5207lp_driver = {
	159	.driver = {
	160	.name = "lv5207lp",
161	},
162	.probe = lv5207lp_probe,
163	.remove = lv5207lp_remove,
164	.id_table = lv5207lp_ids,
165	};
166
167	module_i2c_driver(lv5207lp_driver);
168
169	MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver");
170	MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
171	MODULE_LICENSE("GPL");