mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 02:39:48 +00:00
![Paul Gortmaker](/assets/img/avatar_default.png)
The Kconfig currently controlling compilation of this code is: drivers/leds/Kconfig:config LEDS_SYSCON drivers/leds/Kconfig: bool "LED support for LEDs on system controllers" ...meaning that it currently is not being built as a module by anyone. Lets remove the modular code that is essentially orphaned, so that when reading the driver there is no doubt it is builtin-only. We explicitly disallow a driver unbind, since that doesn't have a sensible use case anyway, and it allows us to drop the ".remove" code for non-modular drivers. Since module_platform_driver() uses the same init level priority as builtin_platform_driver() the init ordering remains unchanged with this commit. Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code. Cc: Richard Purdie <rpurdie@rpsys.net> Cc: linux-leds@vger.kernel.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
155 lines
3.9 KiB
C
155 lines
3.9 KiB
C
/*
|
|
* Generic Syscon LEDs Driver
|
|
*
|
|
* Copyright (c) 2014, Linaro Limited
|
|
* Author: Linus Walleij <linus.walleij@linaro.org>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License as
|
|
* published by the Free Software Foundation; either version 2 of
|
|
* the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
|
* MA 02111-1307 USA
|
|
*/
|
|
#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 device *dev = &pdev->dev;
|
|
struct device_node *np = dev->of_node;
|
|
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(parent->of_node);
|
|
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;
|
|
sled->cdev.name =
|
|
of_get_property(np, "label", NULL) ? : np->name;
|
|
sled->cdev.default_trigger =
|
|
of_get_property(np, "linux,default-trigger", NULL);
|
|
|
|
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;
|
|
|
|
ret = led_classdev_register(dev, &sled->cdev);
|
|
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);
|