backlight: rt4831: Adds support for Richtek RT4831 backlight
Adds support for Richtek RT4831 backlight. Signed-off-by: ChiYuan Huang <cy_huang@richtek.com> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
This commit is contained in:
ChiYuan Huang
Lee Jones
parent
f3e6c298e3
commit
190ccab318
|
|
@ -289,6 +289,14 @@ config BACKLIGHT_QCOM_WLED
|
|||
If you have the Qualcomm PMIC, say Y to enable a driver for the
|
||||
WLED block. Currently it supports PM8941 and PMI8998.
|
||||
|
||||
config BACKLIGHT_RT4831
|
||||
tristate "Richtek RT4831 Backlight Driver"
|
||||
depends on MFD_RT4831
|
||||
help
|
||||
This enables support for Richtek RT4831 Backlight driver.
|
||||
It's commonly used to drive the display WLED. There're four channels
|
||||
inisde, and each channel can provide up to 30mA current.
|
||||
|
||||
config BACKLIGHT_SAHARA
|
||||
tristate "Tabletkiosk Sahara Touch-iT Backlight Driver"
|
||||
depends on X86
|
||||
|
|
|
|||
|
|
@ -49,6 +49,7 @@ obj-$(CONFIG_BACKLIGHT_PANDORA) += pandora_bl.o
|
|||
obj-$(CONFIG_BACKLIGHT_PCF50633) += pcf50633-backlight.o
|
||||
obj-$(CONFIG_BACKLIGHT_PWM) += pwm_bl.o
|
||||
obj-$(CONFIG_BACKLIGHT_QCOM_WLED) += qcom-wled.o
|
||||
obj-$(CONFIG_BACKLIGHT_RT4831) += rt4831-backlight.o
|
||||
obj-$(CONFIG_BACKLIGHT_SAHARA) += kb3886_bl.o
|
||||
obj-$(CONFIG_BACKLIGHT_SKY81452) += sky81452-backlight.o
|
||||
obj-$(CONFIG_BACKLIGHT_TOSA) += tosa_bl.o
|
||||
|
|
|
|||
|
|
@ -0,0 +1,203 @@
|
|||
// 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 <cy_huang@richtek.com>");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
Loading…
Reference in New Issue