forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
203 lines
5.1 KiB
203 lines
5.1 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
|
|
#include <dt-bindings/leds/rt4831-backlight.h> |
|
#include <linux/backlight.h> |
|
#include <linux/bitops.h> |
|
#include <linux/kernel.h> |
|
#include <linux/module.h> |
|
#include <linux/platform_device.h> |
|
#include <linux/property.h> |
|
#include <linux/regmap.h> |
|
|
|
#define RT4831_REG_BLCFG 0x02 |
|
#define RT4831_REG_BLDIML 0x04 |
|
#define RT4831_REG_ENABLE 0x08 |
|
|
|
#define RT4831_BLMAX_BRIGHTNESS 2048 |
|
|
|
#define RT4831_BLOVP_MASK GENMASK(7, 5) |
|
#define RT4831_BLOVP_SHIFT 5 |
|
#define RT4831_BLPWMEN_MASK BIT(0) |
|
#define RT4831_BLEN_MASK BIT(4) |
|
#define RT4831_BLCH_MASK GENMASK(3, 0) |
|
#define RT4831_BLDIML_MASK GENMASK(2, 0) |
|
#define RT4831_BLDIMH_MASK GENMASK(10, 3) |
|
#define RT4831_BLDIMH_SHIFT 3 |
|
|
|
struct rt4831_priv { |
|
struct device *dev; |
|
struct regmap *regmap; |
|
struct backlight_device *bl; |
|
}; |
|
|
|
static int rt4831_bl_update_status(struct backlight_device *bl_dev) |
|
{ |
|
struct rt4831_priv *priv = bl_get_data(bl_dev); |
|
int brightness = backlight_get_brightness(bl_dev); |
|
unsigned int enable = brightness ? RT4831_BLEN_MASK : 0; |
|
u8 v[2]; |
|
int ret; |
|
|
|
if (brightness) { |
|
v[0] = (brightness - 1) & RT4831_BLDIML_MASK; |
|
v[1] = ((brightness - 1) & RT4831_BLDIMH_MASK) >> RT4831_BLDIMH_SHIFT; |
|
|
|
ret = regmap_raw_write(priv->regmap, RT4831_REG_BLDIML, v, sizeof(v)); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
return regmap_update_bits(priv->regmap, RT4831_REG_ENABLE, RT4831_BLEN_MASK, enable); |
|
|
|
} |
|
|
|
static int rt4831_bl_get_brightness(struct backlight_device *bl_dev) |
|
{ |
|
struct rt4831_priv *priv = bl_get_data(bl_dev); |
|
unsigned int val; |
|
u8 v[2]; |
|
int ret; |
|
|
|
ret = regmap_read(priv->regmap, RT4831_REG_ENABLE, &val); |
|
if (ret) |
|
return ret; |
|
|
|
if (!(val & RT4831_BLEN_MASK)) |
|
return 0; |
|
|
|
ret = regmap_raw_read(priv->regmap, RT4831_REG_BLDIML, v, sizeof(v)); |
|
if (ret) |
|
return ret; |
|
|
|
ret = (v[1] << RT4831_BLDIMH_SHIFT) + (v[0] & RT4831_BLDIML_MASK) + 1; |
|
|
|
return ret; |
|
} |
|
|
|
static const struct backlight_ops rt4831_bl_ops = { |
|
.options = BL_CORE_SUSPENDRESUME, |
|
.update_status = rt4831_bl_update_status, |
|
.get_brightness = rt4831_bl_get_brightness, |
|
}; |
|
|
|
static int rt4831_parse_backlight_properties(struct rt4831_priv *priv, |
|
struct backlight_properties *bl_props) |
|
{ |
|
struct device *dev = priv->dev; |
|
u8 propval; |
|
u32 brightness; |
|
unsigned int val = 0; |
|
int ret; |
|
|
|
/* common properties */ |
|
ret = device_property_read_u32(dev, "max-brightness", &brightness); |
|
if (ret) |
|
brightness = RT4831_BLMAX_BRIGHTNESS; |
|
|
|
bl_props->max_brightness = min_t(u32, brightness, RT4831_BLMAX_BRIGHTNESS); |
|
|
|
ret = device_property_read_u32(dev, "default-brightness", &brightness); |
|
if (ret) |
|
brightness = bl_props->max_brightness; |
|
|
|
bl_props->brightness = min_t(u32, brightness, bl_props->max_brightness); |
|
|
|
/* vendor properties */ |
|
if (device_property_read_bool(dev, "richtek,pwm-enable")) |
|
val = RT4831_BLPWMEN_MASK; |
|
|
|
ret = regmap_update_bits(priv->regmap, RT4831_REG_BLCFG, RT4831_BLPWMEN_MASK, val); |
|
if (ret) |
|
return ret; |
|
|
|
ret = device_property_read_u8(dev, "richtek,bled-ovp-sel", &propval); |
|
if (ret) |
|
propval = RT4831_BLOVPLVL_21V; |
|
|
|
propval = min_t(u8, propval, RT4831_BLOVPLVL_29V); |
|
ret = regmap_update_bits(priv->regmap, RT4831_REG_BLCFG, RT4831_BLOVP_MASK, |
|
propval << RT4831_BLOVP_SHIFT); |
|
if (ret) |
|
return ret; |
|
|
|
ret = device_property_read_u8(dev, "richtek,channel-use", &propval); |
|
if (ret) { |
|
dev_err(dev, "richtek,channel-use DT property missing\n"); |
|
return ret; |
|
} |
|
|
|
if (!(propval & RT4831_BLCH_MASK)) { |
|
dev_err(dev, "No channel specified\n"); |
|
return -EINVAL; |
|
} |
|
|
|
return regmap_update_bits(priv->regmap, RT4831_REG_ENABLE, RT4831_BLCH_MASK, propval); |
|
} |
|
|
|
static int rt4831_bl_probe(struct platform_device *pdev) |
|
{ |
|
struct rt4831_priv *priv; |
|
struct backlight_properties bl_props = { .type = BACKLIGHT_RAW, |
|
.scale = BACKLIGHT_SCALE_LINEAR }; |
|
int ret; |
|
|
|
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); |
|
if (!priv) |
|
return -ENOMEM; |
|
|
|
priv->dev = &pdev->dev; |
|
|
|
priv->regmap = dev_get_regmap(pdev->dev.parent, NULL); |
|
if (!priv->regmap) { |
|
dev_err(&pdev->dev, "Failed to init regmap\n"); |
|
return -ENODEV; |
|
} |
|
|
|
ret = rt4831_parse_backlight_properties(priv, &bl_props); |
|
if (ret) { |
|
dev_err(&pdev->dev, "Failed to parse backlight properties\n"); |
|
return ret; |
|
} |
|
|
|
priv->bl = devm_backlight_device_register(&pdev->dev, pdev->name, &pdev->dev, priv, |
|
&rt4831_bl_ops, &bl_props); |
|
if (IS_ERR(priv->bl)) { |
|
dev_err(&pdev->dev, "Failed to register backlight\n"); |
|
return PTR_ERR(priv->bl); |
|
} |
|
|
|
backlight_update_status(priv->bl); |
|
platform_set_drvdata(pdev, priv); |
|
|
|
return 0; |
|
} |
|
|
|
static int rt4831_bl_remove(struct platform_device *pdev) |
|
{ |
|
struct rt4831_priv *priv = platform_get_drvdata(pdev); |
|
struct backlight_device *bl_dev = priv->bl; |
|
|
|
bl_dev->props.brightness = 0; |
|
backlight_update_status(priv->bl); |
|
|
|
return 0; |
|
} |
|
|
|
static const struct of_device_id __maybe_unused rt4831_bl_of_match[] = { |
|
{ .compatible = "richtek,rt4831-backlight", }, |
|
{} |
|
}; |
|
MODULE_DEVICE_TABLE(of, rt4831_bl_of_match); |
|
|
|
static struct platform_driver rt4831_bl_driver = { |
|
.driver = { |
|
.name = "rt4831-backlight", |
|
.of_match_table = rt4831_bl_of_match, |
|
}, |
|
.probe = rt4831_bl_probe, |
|
.remove = rt4831_bl_remove, |
|
}; |
|
module_platform_driver(rt4831_bl_driver); |
|
|
|
MODULE_AUTHOR("ChiYuan Huang <[email protected]>"); |
|
MODULE_LICENSE("GPL v2");
|
|
|