linux/drivers/leds/leds-syscon.c
Marek Behún c49d6cab0d leds: parse linux,default-trigger DT property in LED core
Do the parsing of `linux,default-trigger` DT property to LED core.
Currently it is done in many different drivers and the code is repeated.

This patch removes the parsing from 23 drivers:
  an30259a, aw2013, bcm6328, bcm6358, cr0014114, el15203000, gpio,
  is31fl32xx, lm3532, lm36274, lm3692x, lm3697, lp50xx, lp8860, lt3593,
  max77650, mt6323, ns2, pm8058, pwm, syscon, tlc591xx and turris-omnia.

There is one driver in drivers/input which parses this property on it's
own. I shall send a separate patch there after this is applied.

There are still 8 drivers that parse this property on their own because
they do not pass the led_init_data structure to the registering
function. I will try to refactor those in the future.

Signed-off-by: Marek Behún <marek.behun@nic.cz>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-09-26 21:56:43 +02:00

141 lines
3.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Generic Syscon LEDs Driver
*
* Copyright (c) 2014, Linaro Limited
* Author: Linus Walleij <linus.walleij@linaro.org>
*/
#include <linux/io.h>
#include <linux/init.h>
#include <linux/of_device.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <linux/leds.h>
/**
* struct syscon_led - state container for syscon based LEDs
* @cdev: LED class device for this LED
* @map: regmap to access the syscon device backing this LED
* @offset: the offset into the syscon regmap for the LED register
* @mask: the bit in the register corresponding to the LED
* @state: current state of the LED
*/
struct syscon_led {
struct led_classdev cdev;
struct regmap *map;
u32 offset;
u32 mask;
bool state;
};
static void syscon_led_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
struct syscon_led *sled =
container_of(led_cdev, struct syscon_led, cdev);
u32 val;
int ret;
if (value == LED_OFF) {
val = 0;
sled->state = false;
} else {
val = sled->mask;
sled->state = true;
}
ret = regmap_update_bits(sled->map, sled->offset, sled->mask, val);
if (ret < 0)
dev_err(sled->cdev.dev, "error updating LED status\n");
}
static int syscon_led_probe(struct platform_device *pdev)
{
struct led_init_data init_data = {};
struct device *dev = &pdev->dev;
struct device_node *np = dev_of_node(dev);
struct device *parent;
struct regmap *map;
struct syscon_led *sled;
const char *state;
int ret;
parent = dev->parent;
if (!parent) {
dev_err(dev, "no parent for syscon LED\n");
return -ENODEV;
}
map = syscon_node_to_regmap(dev_of_node(parent));
if (IS_ERR(map)) {
dev_err(dev, "no regmap for syscon LED parent\n");
return PTR_ERR(map);
}
sled = devm_kzalloc(dev, sizeof(*sled), GFP_KERNEL);
if (!sled)
return -ENOMEM;
sled->map = map;
if (of_property_read_u32(np, "offset", &sled->offset))
return -EINVAL;
if (of_property_read_u32(np, "mask", &sled->mask))
return -EINVAL;
state = of_get_property(np, "default-state", NULL);
if (state) {
if (!strcmp(state, "keep")) {
u32 val;
ret = regmap_read(map, sled->offset, &val);
if (ret < 0)
return ret;
sled->state = !!(val & sled->mask);
} else if (!strcmp(state, "on")) {
sled->state = true;
ret = regmap_update_bits(map, sled->offset,
sled->mask,
sled->mask);
if (ret < 0)
return ret;
} else {
sled->state = false;
ret = regmap_update_bits(map, sled->offset,
sled->mask, 0);
if (ret < 0)
return ret;
}
}
sled->cdev.brightness_set = syscon_led_set;
init_data.fwnode = of_fwnode_handle(np);
ret = devm_led_classdev_register_ext(dev, &sled->cdev, &init_data);
if (ret < 0)
return ret;
platform_set_drvdata(pdev, sled);
dev_info(dev, "registered LED %s\n", sled->cdev.name);
return 0;
}
static const struct of_device_id of_syscon_leds_match[] = {
{ .compatible = "register-bit-led", },
{},
};
static struct platform_driver syscon_led_driver = {
.probe = syscon_led_probe,
.driver = {
.name = "leds-syscon",
.of_match_table = of_syscon_leds_match,
.suppress_bind_attrs = true,
},
};
builtin_platform_driver(syscon_led_driver);