tegrakernel/kernel/kernel-4.9/arch/arm/mach-ebsa110/leds.c

72 lines
1.4 KiB
C

/*
* Driver for the LED found on the EBSA110 machine
* Based on Versatile and RealView machine LED code
*
* License terms: GNU General Public License (GPL) version 2
* Author: Bryan Wu <bryan.wu@canonical.com>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/leds.h>
#include <asm/mach-types.h>
#include "core.h"
#if defined(CONFIG_NEW_LEDS) && defined(CONFIG_LEDS_CLASS)
static void ebsa110_led_set(struct led_classdev *cdev,
enum led_brightness b)
{
u8 reg = __raw_readb(SOFT_BASE);
if (b != LED_OFF)
reg |= 0x80;
else
reg &= ~0x80;
__raw_writeb(reg, SOFT_BASE);
}
static enum led_brightness ebsa110_led_get(struct led_classdev *cdev)
{
u8 reg = __raw_readb(SOFT_BASE);
return (reg & 0x80) ? LED_FULL : LED_OFF;
}
static int __init ebsa110_leds_init(void)
{
struct led_classdev *cdev;
int ret;
if (!machine_is_ebsa110())
return -ENODEV;
cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
if (!cdev)
return -ENOMEM;
cdev->name = "ebsa110:0";
cdev->brightness_set = ebsa110_led_set;
cdev->brightness_get = ebsa110_led_get;
cdev->default_trigger = "heartbeat";
ret = led_classdev_register(NULL, cdev);
if (ret < 0) {
kfree(cdev);
return ret;
}
return 0;
}
/*
* Since we may have triggers on any subsystem, defer registration
* until after subsystem_init.
*/
fs_initcall(ebsa110_leds_init);
#endif