diff options
Diffstat (limited to 'arch/sparc/kernel/led.c')
-rw-r--r-- | arch/sparc/kernel/led.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/arch/sparc/kernel/led.c b/arch/sparc/kernel/led.c new file mode 100644 index 00000000000..2a3afca453c --- /dev/null +++ b/arch/sparc/kernel/led.c @@ -0,0 +1,139 @@ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/proc_fs.h> +#include <linux/string.h> + +#include <asm/auxio.h> + +#define LED_MAX_LENGTH 8 /* maximum chars written to proc file */ + +static inline void led_toggle(void) +{ + unsigned char val = get_auxio(); + unsigned char on, off; + + if (val & AUXIO_LED) { + on = 0; + off = AUXIO_LED; + } else { + on = AUXIO_LED; + off = 0; + } + + set_auxio(on, off); +} + +static struct timer_list led_blink_timer; + +static void led_blink(unsigned long timeout) +{ + led_toggle(); + + /* reschedule */ + if (!timeout) { /* blink according to load */ + led_blink_timer.expires = jiffies + + ((1 + (avenrun[0] >> FSHIFT)) * HZ); + led_blink_timer.data = 0; + } else { /* blink at user specified interval */ + led_blink_timer.expires = jiffies + (timeout * HZ); + led_blink_timer.data = timeout; + } + add_timer(&led_blink_timer); +} + +static int led_read_proc(char *buf, char **start, off_t offset, int count, + int *eof, void *data) +{ + int len = 0; + + if (get_auxio() & AUXIO_LED) + len = sprintf(buf, "on\n"); + else + len = sprintf(buf, "off\n"); + + return len; +} + +static int led_write_proc(struct file *file, const char *buffer, + unsigned long count, void *data) +{ + char *buf = NULL; + + if (count > LED_MAX_LENGTH) + count = LED_MAX_LENGTH; + + buf = kmalloc(sizeof(char) * (count + 1), GFP_KERNEL); + if (!buf) + return -ENOMEM; + + if (copy_from_user(buf, buffer, count)) { + kfree(buf); + return -EFAULT; + } + + buf[count] = '\0'; + + /* work around \n when echo'ing into proc */ + if (buf[count - 1] == '\n') + buf[count - 1] = '\0'; + + /* before we change anything we want to stop any running timers, + * otherwise calls such as on will have no persistent effect + */ + del_timer_sync(&led_blink_timer); + + if (!strcmp(buf, "on")) { + auxio_set_led(AUXIO_LED_ON); + } else if (!strcmp(buf, "toggle")) { + led_toggle(); + } else if ((*buf > '0') && (*buf <= '9')) { + led_blink(simple_strtoul(buf, NULL, 10)); + } else if (!strcmp(buf, "load")) { + led_blink(0); + } else { + auxio_set_led(AUXIO_LED_OFF); + } + + kfree(buf); + + return count; +} + +static struct proc_dir_entry *led; + +#define LED_VERSION "0.1" + +static int __init led_init(void) +{ + init_timer(&led_blink_timer); + led_blink_timer.function = led_blink; + + led = create_proc_entry("led", 0, NULL); + if (!led) + return -ENOMEM; + + led->read_proc = led_read_proc; /* reader function */ + led->write_proc = led_write_proc; /* writer function */ + led->owner = THIS_MODULE; + + printk(KERN_INFO + "led: version %s, Lars Kotthoff <metalhead@metalhead.ws>\n", + LED_VERSION); + + return 0; +} + +static void __exit led_exit(void) +{ + remove_proc_entry("led", NULL); + del_timer_sync(&led_blink_timer); +} + +module_init(led_init); +module_exit(led_exit); + +MODULE_AUTHOR("Lars Kotthoff <metalhead@metalhead.ws>"); +MODULE_DESCRIPTION("Provides control of the front LED on SPARC systems."); +MODULE_LICENSE("GPL"); +MODULE_VERSION(LED_VERSION); |