mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-06 02:24:14 +08:00
d2912cb15b
Based on 2 normalized pattern(s): 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 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 # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
209 lines
5.1 KiB
C
209 lines
5.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Backlight driver for Maxim MAX8925
|
|
*
|
|
* Copyright (C) 2009 Marvell International Ltd.
|
|
* Haojian Zhuang <haojian.zhuang@marvell.com>
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/fb.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/backlight.h>
|
|
#include <linux/mfd/max8925.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/module.h>
|
|
|
|
#define MAX_BRIGHTNESS (0xff)
|
|
#define MIN_BRIGHTNESS (0)
|
|
|
|
#define LWX_FREQ(x) (((x - 601) / 100) & 0x7)
|
|
|
|
struct max8925_backlight_data {
|
|
struct max8925_chip *chip;
|
|
|
|
int current_brightness;
|
|
int reg_mode_cntl;
|
|
int reg_cntl;
|
|
};
|
|
|
|
static int max8925_backlight_set(struct backlight_device *bl, int brightness)
|
|
{
|
|
struct max8925_backlight_data *data = bl_get_data(bl);
|
|
struct max8925_chip *chip = data->chip;
|
|
unsigned char value;
|
|
int ret;
|
|
|
|
if (brightness > MAX_BRIGHTNESS)
|
|
value = MAX_BRIGHTNESS;
|
|
else
|
|
value = brightness;
|
|
|
|
ret = max8925_reg_write(chip->i2c, data->reg_cntl, value);
|
|
if (ret < 0)
|
|
goto out;
|
|
|
|
if (!data->current_brightness && brightness)
|
|
/* enable WLED output */
|
|
ret = max8925_set_bits(chip->i2c, data->reg_mode_cntl, 1, 1);
|
|
else if (!brightness)
|
|
/* disable WLED output */
|
|
ret = max8925_set_bits(chip->i2c, data->reg_mode_cntl, 1, 0);
|
|
if (ret < 0)
|
|
goto out;
|
|
dev_dbg(chip->dev, "set brightness %d\n", value);
|
|
data->current_brightness = value;
|
|
return 0;
|
|
out:
|
|
dev_dbg(chip->dev, "set brightness %d failure with return value:%d\n",
|
|
value, ret);
|
|
return ret;
|
|
}
|
|
|
|
static int max8925_backlight_update_status(struct backlight_device *bl)
|
|
{
|
|
int brightness = bl->props.brightness;
|
|
|
|
if (bl->props.power != FB_BLANK_UNBLANK)
|
|
brightness = 0;
|
|
|
|
if (bl->props.fb_blank != FB_BLANK_UNBLANK)
|
|
brightness = 0;
|
|
|
|
if (bl->props.state & BL_CORE_SUSPENDED)
|
|
brightness = 0;
|
|
|
|
return max8925_backlight_set(bl, brightness);
|
|
}
|
|
|
|
static int max8925_backlight_get_brightness(struct backlight_device *bl)
|
|
{
|
|
struct max8925_backlight_data *data = bl_get_data(bl);
|
|
struct max8925_chip *chip = data->chip;
|
|
int ret;
|
|
|
|
ret = max8925_reg_read(chip->i2c, data->reg_cntl);
|
|
if (ret < 0)
|
|
return -EINVAL;
|
|
data->current_brightness = ret;
|
|
dev_dbg(chip->dev, "get brightness %d\n", data->current_brightness);
|
|
return ret;
|
|
}
|
|
|
|
static const struct backlight_ops max8925_backlight_ops = {
|
|
.options = BL_CORE_SUSPENDRESUME,
|
|
.update_status = max8925_backlight_update_status,
|
|
.get_brightness = max8925_backlight_get_brightness,
|
|
};
|
|
|
|
static void max8925_backlight_dt_init(struct platform_device *pdev)
|
|
{
|
|
struct device_node *nproot = pdev->dev.parent->of_node, *np;
|
|
struct max8925_backlight_pdata *pdata;
|
|
u32 val;
|
|
|
|
if (!nproot || !IS_ENABLED(CONFIG_OF))
|
|
return;
|
|
|
|
pdata = devm_kzalloc(&pdev->dev,
|
|
sizeof(struct max8925_backlight_pdata),
|
|
GFP_KERNEL);
|
|
if (!pdata)
|
|
return;
|
|
|
|
np = of_get_child_by_name(nproot, "backlight");
|
|
if (!np) {
|
|
dev_err(&pdev->dev, "failed to find backlight node\n");
|
|
return;
|
|
}
|
|
|
|
if (!of_property_read_u32(np, "maxim,max8925-dual-string", &val))
|
|
pdata->dual_string = val;
|
|
|
|
of_node_put(np);
|
|
|
|
pdev->dev.platform_data = pdata;
|
|
}
|
|
|
|
static int max8925_backlight_probe(struct platform_device *pdev)
|
|
{
|
|
struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
|
|
struct max8925_backlight_pdata *pdata;
|
|
struct max8925_backlight_data *data;
|
|
struct backlight_device *bl;
|
|
struct backlight_properties props;
|
|
struct resource *res;
|
|
unsigned char value;
|
|
int ret = 0;
|
|
|
|
data = devm_kzalloc(&pdev->dev, sizeof(struct max8925_backlight_data),
|
|
GFP_KERNEL);
|
|
if (data == NULL)
|
|
return -ENOMEM;
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_REG, 0);
|
|
if (!res) {
|
|
dev_err(&pdev->dev, "No REG resource for mode control!\n");
|
|
return -ENXIO;
|
|
}
|
|
data->reg_mode_cntl = res->start;
|
|
res = platform_get_resource(pdev, IORESOURCE_REG, 1);
|
|
if (!res) {
|
|
dev_err(&pdev->dev, "No REG resource for control!\n");
|
|
return -ENXIO;
|
|
}
|
|
data->reg_cntl = res->start;
|
|
|
|
data->chip = chip;
|
|
data->current_brightness = 0;
|
|
|
|
memset(&props, 0, sizeof(struct backlight_properties));
|
|
props.type = BACKLIGHT_RAW;
|
|
props.max_brightness = MAX_BRIGHTNESS;
|
|
bl = devm_backlight_device_register(&pdev->dev, "max8925-backlight",
|
|
&pdev->dev, data,
|
|
&max8925_backlight_ops, &props);
|
|
if (IS_ERR(bl)) {
|
|
dev_err(&pdev->dev, "failed to register backlight\n");
|
|
return PTR_ERR(bl);
|
|
}
|
|
bl->props.brightness = MAX_BRIGHTNESS;
|
|
|
|
platform_set_drvdata(pdev, bl);
|
|
|
|
value = 0;
|
|
if (!pdev->dev.platform_data)
|
|
max8925_backlight_dt_init(pdev);
|
|
|
|
pdata = pdev->dev.platform_data;
|
|
if (pdata) {
|
|
if (pdata->lxw_scl)
|
|
value |= (1 << 7);
|
|
if (pdata->lxw_freq)
|
|
value |= (LWX_FREQ(pdata->lxw_freq) << 4);
|
|
if (pdata->dual_string)
|
|
value |= (1 << 1);
|
|
}
|
|
ret = max8925_set_bits(chip->i2c, data->reg_mode_cntl, 0xfe, value);
|
|
if (ret < 0)
|
|
return ret;
|
|
backlight_update_status(bl);
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver max8925_backlight_driver = {
|
|
.driver = {
|
|
.name = "max8925-backlight",
|
|
},
|
|
.probe = max8925_backlight_probe,
|
|
};
|
|
|
|
module_platform_driver(max8925_backlight_driver);
|
|
|
|
MODULE_DESCRIPTION("Backlight Driver for Maxim MAX8925");
|
|
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:max8925-backlight");
|