https://github.com/torvalds/linux
Tip revision: 1001354ca34179f3db924eb66672442a173147dc authored by Linus Torvalds on 15 October 2016, 19:17:50 UTC
Linux 4.9-rc1
Linux 4.9-rc1
Tip revision: 1001354
leds-versatile.c
/*
* Driver for the 8 user LEDs found on the RealViews and Versatiles
* Based on DaVinci's DM365 board code
*
* License terms: GNU General Public License (GPL) version 2
* Author: Linus Walleij <triad@df.lth.se>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/leds.h>
#include <linux/platform_device.h>
struct versatile_led {
void __iomem *base;
struct led_classdev cdev;
u8 mask;
};
/*
* The triggers lines up below will only be used if the
* LED triggers are compiled in.
*/
static const struct {
const char *name;
const char *trigger;
} versatile_leds[] = {
{ "versatile:0", "heartbeat", },
{ "versatile:1", "mmc0", },
{ "versatile:2", "cpu0" },
{ "versatile:3", "cpu1" },
{ "versatile:4", "cpu2" },
{ "versatile:5", "cpu3" },
{ "versatile:6", },
{ "versatile:7", },
};
static void versatile_led_set(struct led_classdev *cdev,
enum led_brightness b)
{
struct versatile_led *led = container_of(cdev,
struct versatile_led, cdev);
u32 reg = readl(led->base);
if (b != LED_OFF)
reg |= led->mask;
else
reg &= ~led->mask;
writel(reg, led->base);
}
static enum led_brightness versatile_led_get(struct led_classdev *cdev)
{
struct versatile_led *led = container_of(cdev,
struct versatile_led, cdev);
u32 reg = readl(led->base);
return (reg & led->mask) ? LED_FULL : LED_OFF;
}
static int versatile_leds_probe(struct platform_device *dev)
{
int i;
struct resource *res;
void __iomem *base;
res = platform_get_resource(dev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(&dev->dev, res);
if (IS_ERR(base))
return PTR_ERR(base);
/* All off */
writel(0, base);
for (i = 0; i < ARRAY_SIZE(versatile_leds); i++) {
struct versatile_led *led;
led = kzalloc(sizeof(*led), GFP_KERNEL);
if (!led)
break;
led->base = base;
led->cdev.name = versatile_leds[i].name;
led->cdev.brightness_set = versatile_led_set;
led->cdev.brightness_get = versatile_led_get;
led->cdev.default_trigger = versatile_leds[i].trigger;
led->mask = BIT(i);
if (led_classdev_register(NULL, &led->cdev) < 0) {
kfree(led);
break;
}
}
return 0;
}
static struct platform_driver versatile_leds_driver = {
.driver = {
.name = "versatile-leds",
},
.probe = versatile_leds_probe,
};
module_platform_driver(versatile_leds_driver);
MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
MODULE_DESCRIPTION("ARM Versatile LED driver");
MODULE_LICENSE("GPL v2");