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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2011 Texas Instruments
* Copyright (c) 2024 Svyatoslav Ryhel <clamor95@gmail.com>
*/
#define LOG_CATEGORY UCLASS_PANEL_BACKLIGHT
#include <malloc.h>
#include <backlight.h>
#include <dm.h>
#include <dm/devres.h>
#include <i2c.h>
#include <log.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <asm/gpio.h>
#include <power/regulator.h>
#define LP855x_MIN_BRIGHTNESS 0x00
#define LP855x_MAX_BRIGHTNESS 0xff
/* LP8550/1/2/3/6 Registers */
#define LP855X_BRIGHTNESS_CTRL 0x00
#define LP855X_DEVICE_CTRL 0x01
#define LP855X_EEPROM_START 0xa0
#define LP855X_EEPROM_END 0xa7
#define LP8556_EPROM_START 0x98
#define LP8556_EPROM_END 0xaf
/* LP8555/7 Registers */
#define LP8557_BL_CMD 0x00
#define LP8557_BL_MASK 0x01
#define LP8557_BL_ON 0x01
#define LP8557_BL_OFF 0x00
#define LP8557_BRIGHTNESS_CTRL 0x04
#define LP8557_CONFIG 0x10
#define LP8555_EPROM_START 0x10
#define LP8555_EPROM_END 0x7a
#define LP8557_EPROM_START 0x10
#define LP8557_EPROM_END 0x1e
struct lp855x_rom_data {
u8 addr;
u8 val;
};
struct lp855x_backlight_priv;
/*
* struct lp855x_device_config
* @pre_init_device: init device function call before updating the brightness
* @reg_brightness: register address for brigthenss control
* @reg_devicectrl: register address for device control
* @post_init_device: late init device function call
*/
struct lp855x_device_config {
int (*pre_init_device)(struct udevice *dev);
u8 reg_brightness;
u8 reg_devicectrl;
u8 reg_eepromstart;
u8 reg_eepromend;
int (*post_init_device)(struct udevice *dev);
};
struct lp855x_backlight_priv {
struct udevice *supply; /* regulator for VDD input */
struct udevice *enable; /* regulator for EN/VDDIO input */
u8 device_control;
u8 initial_brightness;
int size_program;
struct lp855x_rom_data *rom_data;
struct lp855x_device_config *cfg;
};
static int lp855x_backlight_enable(struct udevice *dev)
{
struct lp855x_backlight_priv *priv = dev_get_priv(dev);
int ret;
ret = regulator_set_enable_if_allowed(priv->supply, 1);
if (ret) {
log_debug("%s: enabling power-supply failed (%d)\n",
__func__, ret);
return ret;
}
ret = regulator_set_enable_if_allowed(priv->enable, 1);
if (ret) {
log_debug("%s: enabling enable-supply failed (%d)\n",
__func__, ret);
return ret;
}
mdelay(2);
if (priv->cfg->pre_init_device) {
ret = priv->cfg->pre_init_device(dev);
if (ret) {
log_debug("%s: pre init device err: %d\n",
__func__, ret);
return ret;
}
}
ret = dm_i2c_reg_write(dev, priv->cfg->reg_brightness,
priv->initial_brightness);
if (ret)
return ret;
ret = dm_i2c_reg_write(dev, priv->cfg->reg_devicectrl,
priv->device_control);
if (ret)
return ret;
if (priv->size_program > 0) {
int i;
u8 val, addr;
for (i = 0; i < priv->size_program; i++) {
addr = priv->rom_data[i].addr;
val = priv->rom_data[i].val;
if (addr < priv->cfg->reg_eepromstart &&
addr > priv->cfg->reg_eepromend)
continue;
ret = dm_i2c_reg_write(dev, addr, val);
if (ret)
return ret;
}
}
if (priv->cfg->post_init_device) {
ret = priv->cfg->post_init_device(dev);
if (ret) {
log_debug("%s: post init device err: %d\n",
__func__, ret);
return ret;
}
}
return 0;
}
static int lp855x_backlight_set_brightness(struct udevice *dev, int percent)
{
struct lp855x_backlight_priv *priv = dev_get_priv(dev);
if (percent == BACKLIGHT_DEFAULT)
percent = priv->initial_brightness;
if (percent < LP855x_MIN_BRIGHTNESS)
percent = LP855x_MIN_BRIGHTNESS;
if (percent > LP855x_MAX_BRIGHTNESS)
percent = LP855x_MAX_BRIGHTNESS;
/* Set brightness level */
return dm_i2c_reg_write(dev, priv->cfg->reg_brightness,
percent);
}
static int lp855x_backlight_probe(struct udevice *dev)
{
struct lp855x_backlight_priv *priv = dev_get_priv(dev);
int rom_length, ret;
if (device_get_uclass_id(dev->parent) != UCLASS_I2C)
return -EPROTONOSUPPORT;
priv->cfg = (struct lp855x_device_config *)dev_get_driver_data(dev);
dev_read_u8(dev, "dev-ctrl", &priv->device_control);
dev_read_u8(dev, "init-brt", &priv->initial_brightness);
/* Fill ROM platform data if defined */
rom_length = dev_get_child_count(dev);
if (rom_length > 0) {
struct lp855x_rom_data *rom;
ofnode child;
int i = 0;
rom = devm_kcalloc(dev, rom_length, sizeof(*rom), GFP_KERNEL);
if (!rom)
return -ENOMEM;
dev_for_each_subnode(child, dev) {
ofnode_read_u8(child, "rom-addr", &rom[i].addr);
ofnode_read_u8(child, "rom-val", &rom[i].val);
i++;
}
priv->size_program = rom_length;
priv->rom_data = &rom[0];
}
ret = uclass_get_device_by_phandle(UCLASS_REGULATOR, dev,
"power-supply", &priv->supply);
if (ret) {
log_err("%s: cannot get power-supply: ret = %d\n", __func__, ret);
return ret;
}
ret = uclass_get_device_by_phandle(UCLASS_REGULATOR, dev,
"enable-supply", &priv->enable);
if (ret) {
log_err("%s: cannot get enable-supply: ret = %d\n", __func__, ret);
return ret;
}
return 0;
}
static const struct backlight_ops lp855x_backlight_ops = {
.enable = lp855x_backlight_enable,
.set_brightness = lp855x_backlight_set_brightness,
};
static int lp8556_bl_rst(struct udevice *dev)
{
int ret;
/* Reset backlight after updating EPROM settings */
ret = dm_i2c_reg_clrset(dev, LP855X_DEVICE_CTRL, LP8557_BL_MASK,
LP8557_BL_OFF);
if (ret)
return ret;
mdelay(10);
return dm_i2c_reg_clrset(dev, LP855X_DEVICE_CTRL, LP8557_BL_MASK,
LP8557_BL_ON);
}
static int lp8557_bl_off(struct udevice *dev)
{
/* BL_ON = 0 before updating EPROM settings */
return dm_i2c_reg_clrset(dev, LP8557_BL_CMD, LP8557_BL_MASK,
LP8557_BL_OFF);
}
static int lp8557_bl_on(struct udevice *dev)
{
/* BL_ON = 1 after updating EPROM settings */
return dm_i2c_reg_clrset(dev, LP8557_BL_CMD, LP8557_BL_MASK,
LP8557_BL_ON);
}
static struct lp855x_device_config lp855x_dev_cfg = {
.reg_brightness = LP855X_BRIGHTNESS_CTRL,
.reg_devicectrl = LP855X_DEVICE_CTRL,
.reg_eepromstart = LP855X_EEPROM_START,
.reg_eepromend = LP855X_EEPROM_END,
};
static struct lp855x_device_config lp8555_dev_cfg = {
.reg_brightness = LP8557_BRIGHTNESS_CTRL,
.reg_devicectrl = LP8557_CONFIG,
.reg_eepromstart = LP8555_EPROM_START,
.reg_eepromend = LP8555_EPROM_END,
.pre_init_device = lp8557_bl_off,
.post_init_device = lp8557_bl_on,
};
static struct lp855x_device_config lp8556_dev_cfg = {
.reg_brightness = LP855X_BRIGHTNESS_CTRL,
.reg_devicectrl = LP855X_DEVICE_CTRL,
.reg_eepromstart = LP8556_EPROM_START,
.reg_eepromend = LP8556_EPROM_END,
.post_init_device = lp8556_bl_rst,
};
static struct lp855x_device_config lp8557_dev_cfg = {
.reg_brightness = LP8557_BRIGHTNESS_CTRL,
.reg_devicectrl = LP8557_CONFIG,
.reg_eepromstart = LP8557_EPROM_START,
.reg_eepromend = LP8557_EPROM_END,
.pre_init_device = lp8557_bl_off,
.post_init_device = lp8557_bl_on,
};
static const struct udevice_id lp855x_backlight_ids[] = {
{ .compatible = "ti,lp8550", .data = (ulong)&lp855x_dev_cfg },
{ .compatible = "ti,lp8551", .data = (ulong)&lp855x_dev_cfg },
{ .compatible = "ti,lp8552", .data = (ulong)&lp855x_dev_cfg },
{ .compatible = "ti,lp8553", .data = (ulong)&lp855x_dev_cfg },
{ .compatible = "ti,lp8555", .data = (ulong)&lp8555_dev_cfg },
{ .compatible = "ti,lp8556", .data = (ulong)&lp8556_dev_cfg },
{ .compatible = "ti,lp8557", .data = (ulong)&lp8557_dev_cfg },
{ }
};
U_BOOT_DRIVER(lp855x_backlight) = {
.name = "lp855x_backlight",
.id = UCLASS_PANEL_BACKLIGHT,
.of_match = lp855x_backlight_ids,
.probe = lp855x_backlight_probe,
.ops = &lp855x_backlight_ops,
.priv_auto = sizeof(struct lp855x_backlight_priv),
};
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