linux-sg2042/arch/arm/mach-integrator/leds.c

125 lines
2.7 KiB
C

/*
* Driver for the 4 user LEDs found on the Integrator AP/CP baseboard
* 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 "hardware.h"
#include "cm.h"
#if defined(CONFIG_NEW_LEDS) && defined(CONFIG_LEDS_CLASS)
#define ALPHA_REG __io_address(INTEGRATOR_DBG_BASE)
#define LEDREG (__io_address(INTEGRATOR_DBG_BASE) + INTEGRATOR_DBG_LEDS_OFFSET)
struct integrator_led {
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;
} integrator_leds[] = {
{ "integrator:green0", "heartbeat", },
{ "integrator:yellow", },
{ "integrator:red", },
{ "integrator:green1", },
{ "integrator:core_module", "cpu0", },
};
static void integrator_led_set(struct led_classdev *cdev,
enum led_brightness b)
{
struct integrator_led *led = container_of(cdev,
struct integrator_led, cdev);
u32 reg = __raw_readl(LEDREG);
if (b != LED_OFF)
reg |= led->mask;
else
reg &= ~led->mask;
while (__raw_readl(ALPHA_REG) & 1)
cpu_relax();
__raw_writel(reg, LEDREG);
}
static enum led_brightness integrator_led_get(struct led_classdev *cdev)
{
struct integrator_led *led = container_of(cdev,
struct integrator_led, cdev);
u32 reg = __raw_readl(LEDREG);
return (reg & led->mask) ? LED_FULL : LED_OFF;
}
static void cm_led_set(struct led_classdev *cdev,
enum led_brightness b)
{
if (b != LED_OFF)
cm_control(CM_CTRL_LED, CM_CTRL_LED);
else
cm_control(CM_CTRL_LED, 0);
}
static enum led_brightness cm_led_get(struct led_classdev *cdev)
{
u32 reg = cm_get();
return (reg & CM_CTRL_LED) ? LED_FULL : LED_OFF;
}
static int __init integrator_leds_init(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(integrator_leds); i++) {
struct integrator_led *led;
led = kzalloc(sizeof(*led), GFP_KERNEL);
if (!led)
break;
led->cdev.name = integrator_leds[i].name;
if (i == 4) { /* Setting for LED in core module */
led->cdev.brightness_set = cm_led_set;
led->cdev.brightness_get = cm_led_get;
} else {
led->cdev.brightness_set = integrator_led_set;
led->cdev.brightness_get = integrator_led_get;
}
led->cdev.default_trigger = integrator_leds[i].trigger;
led->mask = BIT(i);
if (led_classdev_register(NULL, &led->cdev) < 0) {
kfree(led);
break;
}
}
return 0;
}
/*
* Since we may have triggers on any subsystem, defer registration
* until after subsystem_init.
*/
fs_initcall(integrator_leds_init);
#endif