linux-sg2042/drivers/leds/leds-alix2.c

182 lines
3.6 KiB
C

/*
* LEDs driver for PCEngines ALIX.2 and ALIX.3
*
* Copyright (C) 2008 Constantin Baranov <const@mimas.ru>
*/
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/string.h>
static int force = 0;
module_param(force, bool, 0444);
MODULE_PARM_DESC(force, "Assume system has ALIX.2 style LEDs");
struct alix_led {
struct led_classdev cdev;
unsigned short port;
unsigned int on_value;
unsigned int off_value;
};
static void alix_led_set(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
struct alix_led *led_dev =
container_of(led_cdev, struct alix_led, cdev);
if (brightness)
outl(led_dev->on_value, led_dev->port);
else
outl(led_dev->off_value, led_dev->port);
}
static struct alix_led alix_leds[] = {
{
.cdev = {
.name = "alix:1",
.brightness_set = alix_led_set,
},
.port = 0x6100,
.on_value = 1 << 22,
.off_value = 1 << 6,
},
{
.cdev = {
.name = "alix:2",
.brightness_set = alix_led_set,
},
.port = 0x6180,
.on_value = 1 << 25,
.off_value = 1 << 9,
},
{
.cdev = {
.name = "alix:3",
.brightness_set = alix_led_set,
},
.port = 0x6180,
.on_value = 1 << 27,
.off_value = 1 << 11,
},
};
static int __init alix_led_probe(struct platform_device *pdev)
{
int i;
int ret;
for (i = 0; i < ARRAY_SIZE(alix_leds); i++) {
alix_leds[i].cdev.flags |= LED_CORE_SUSPENDRESUME;
ret = led_classdev_register(&pdev->dev, &alix_leds[i].cdev);
if (ret < 0)
goto fail;
}
return 0;
fail:
while (--i >= 0)
led_classdev_unregister(&alix_leds[i].cdev);
return ret;
}
static int alix_led_remove(struct platform_device *pdev)
{
int i;
for (i = 0; i < ARRAY_SIZE(alix_leds); i++)
led_classdev_unregister(&alix_leds[i].cdev);
return 0;
}
static struct platform_driver alix_led_driver = {
.remove = alix_led_remove,
.driver = {
.name = KBUILD_MODNAME,
.owner = THIS_MODULE,
},
};
static int __init alix_present(void)
{
const unsigned long bios_phys = 0x000f0000;
const size_t bios_len = 0x00010000;
const char alix_sig[] = "PC Engines ALIX.";
const size_t alix_sig_len = sizeof(alix_sig) - 1;
const char *bios_virt;
const char *scan_end;
const char *p;
int ret = 0;
if (force) {
printk(KERN_NOTICE "%s: forced to skip BIOS test, "
"assume system has ALIX.2 style LEDs\n",
KBUILD_MODNAME);
ret = 1;
goto out;
}
bios_virt = phys_to_virt(bios_phys);
scan_end = bios_virt + bios_len - (alix_sig_len + 2);
for (p = bios_virt; p < scan_end; p++) {
const char *tail;
if (memcmp(p, alix_sig, alix_sig_len) != 0) {
continue;
}
tail = p + alix_sig_len;
if ((tail[0] == '2' || tail[0] == '3') && tail[1] == '\0') {
printk(KERN_INFO
"%s: system is recognized as \"%s\"\n",
KBUILD_MODNAME, p);
ret = 1;
break;
}
}
out:
return ret;
}
static struct platform_device *pdev;
static int __init alix_led_init(void)
{
int ret;
if (!alix_present()) {
ret = -ENODEV;
goto out;
}
pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
if (!IS_ERR(pdev)) {
ret = platform_driver_probe(&alix_led_driver, alix_led_probe);
if (ret)
platform_device_unregister(pdev);
} else
ret = PTR_ERR(pdev);
out:
return ret;
}
static void __exit alix_led_exit(void)
{
platform_device_unregister(pdev);
platform_driver_unregister(&alix_led_driver);
}
module_init(alix_led_init);
module_exit(alix_led_exit);
MODULE_AUTHOR("Constantin Baranov <const@mimas.ru>");
MODULE_DESCRIPTION("PCEngines ALIX.2 and ALIX.3 LED driver");
MODULE_LICENSE("GPL");