linux/drivers/leds/leds-lp8788.c

172 lines
3.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* TI LP8788 MFD - keyled driver
*
* Copyright 2012 Texas Instruments
*
* Author: Milo(Woogyom) Kim <milo.kim@ti.com>
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/mutex.h>
#include <linux/mfd/lp8788.h>
#include <linux/mfd/lp8788-isink.h>
#define MAX_BRIGHTNESS LP8788_ISINK_MAX_PWM
#define DEFAULT_LED_NAME "keyboard-backlight"
struct lp8788_led {
struct lp8788 *lp;
struct mutex lock;
struct led_classdev led_dev;
enum lp8788_isink_number isink_num;
int on;
};
struct lp8788_led_config {
enum lp8788_isink_scale scale;
enum lp8788_isink_number num;
int iout;
};
static struct lp8788_led_config default_led_config = {
.scale = LP8788_ISINK_SCALE_100mA,
.num = LP8788_ISINK_3,
.iout = 0,
};
static int lp8788_led_init_device(struct lp8788_led *led,
struct lp8788_led_platform_data *pdata)
{
struct lp8788_led_config *cfg = &default_led_config;
u8 addr, mask, val;
int ret;
if (pdata) {
cfg->scale = pdata->scale;
cfg->num = pdata->num;
cfg->iout = pdata->iout_code;
}
led->isink_num = cfg->num;
/* scale configuration */
addr = LP8788_ISINK_CTRL;
mask = 1 << (cfg->num + LP8788_ISINK_SCALE_OFFSET);
val = cfg->scale << (cfg->num + LP8788_ISINK_SCALE_OFFSET);
ret = lp8788_update_bits(led->lp, addr, mask, val);
if (ret)
return ret;
/* current configuration */
addr = lp8788_iout_addr[cfg->num];
mask = lp8788_iout_mask[cfg->num];
val = cfg->iout;
return lp8788_update_bits(led->lp, addr, mask, val);
}
static int lp8788_led_enable(struct lp8788_led *led,
enum lp8788_isink_number num, int on)
{
int ret;
u8 mask = 1 << num;
u8 val = on << num;
ret = lp8788_update_bits(led->lp, LP8788_ISINK_CTRL, mask, val);
if (ret == 0)
led->on = on;
return ret;
}
static int lp8788_brightness_set(struct led_classdev *led_cdev,
enum led_brightness val)
{
struct lp8788_led *led =
container_of(led_cdev, struct lp8788_led, led_dev);
enum lp8788_isink_number num = led->isink_num;
int enable, ret;
mutex_lock(&led->lock);
switch (num) {
case LP8788_ISINK_1:
case LP8788_ISINK_2:
case LP8788_ISINK_3:
ret = lp8788_write_byte(led->lp, lp8788_pwm_addr[num], val);
if (ret < 0)
goto unlock;
break;
default:
mutex_unlock(&led->lock);
return -EINVAL;
}
enable = (val > 0) ? 1 : 0;
if (enable != led->on)
ret = lp8788_led_enable(led, num, enable);
unlock:
mutex_unlock(&led->lock);
return ret;
}
static int lp8788_led_probe(struct platform_device *pdev)
{
struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
struct lp8788_led_platform_data *led_pdata;
struct lp8788_led *led;
struct device *dev = &pdev->dev;
int ret;
led = devm_kzalloc(dev, sizeof(struct lp8788_led), GFP_KERNEL);
if (!led)
return -ENOMEM;
led->lp = lp;
led->led_dev.max_brightness = MAX_BRIGHTNESS;
led->led_dev.brightness_set_blocking = lp8788_brightness_set;
led_pdata = lp->pdata ? lp->pdata->led_pdata : NULL;
if (!led_pdata || !led_pdata->name)
led->led_dev.name = DEFAULT_LED_NAME;
else
led->led_dev.name = led_pdata->name;
mutex_init(&led->lock);
ret = lp8788_led_init_device(led, led_pdata);
if (ret) {
dev_err(dev, "led init device err: %d\n", ret);
return ret;
}
ret = devm_led_classdev_register(dev, &led->led_dev);
if (ret) {
dev_err(dev, "led register err: %d\n", ret);
return ret;
}
return 0;
}
static struct platform_driver lp8788_led_driver = {
.probe = lp8788_led_probe,
.driver = {
.name = LP8788_DEV_KEYLED,
},
};
module_platform_driver(lp8788_led_driver);
MODULE_DESCRIPTION("Texas Instruments LP8788 Keyboard LED Driver");
MODULE_AUTHOR("Milo Kim");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:lp8788-keyled");