diff options
Diffstat (limited to 'arch/sparc/kernel/led.c')
-rw-r--r-- | arch/sparc/kernel/led.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/arch/sparc/kernel/led.c b/arch/sparc/kernel/led.c new file mode 100644 index 000000000..519f5ba7e --- /dev/null +++ b/arch/sparc/kernel/led.c @@ -0,0 +1,146 @@ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/jiffies.h> +#include <linux/timer.h> +#include <linux/uaccess.h> +#include <linux/sched/loadavg.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 unsigned long led_blink_timer_timeout; + +static void led_blink(struct timer_list *unused) +{ + unsigned long timeout = led_blink_timer_timeout; + + led_toggle(); + + /* reschedule */ + if (!timeout) { /* blink according to load */ + led_blink_timer.expires = jiffies + + ((1 + (avenrun[0] >> FSHIFT)) * HZ); + } else { /* blink at user specified interval */ + led_blink_timer.expires = jiffies + (timeout * HZ); + } + add_timer(&led_blink_timer); +} + +static int led_proc_show(struct seq_file *m, void *v) +{ + if (get_auxio() & AUXIO_LED) + seq_puts(m, "on\n"); + else + seq_puts(m, "off\n"); + return 0; +} + +static int led_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, led_proc_show, NULL); +} + +static ssize_t led_proc_write(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos) +{ + char *buf = NULL; + + if (count > LED_MAX_LENGTH) + count = LED_MAX_LENGTH; + + buf = memdup_user_nul(buffer, count); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + /* 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_timer_timeout = simple_strtoul(buf, NULL, 10); + led_blink(&led_blink_timer); + } else if (!strcmp(buf, "load")) { + led_blink_timer_timeout = 0; + led_blink(&led_blink_timer); + } else { + auxio_set_led(AUXIO_LED_OFF); + } + + kfree(buf); + + return count; +} + +static const struct file_operations led_proc_fops = { + .owner = THIS_MODULE, + .open = led_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = led_proc_write, +}; + +static struct proc_dir_entry *led; + +#define LED_VERSION "0.1" + +static int __init led_init(void) +{ + timer_setup(&led_blink_timer, led_blink, 0); + + led = proc_create("led", 0, NULL, &led_proc_fops); + if (!led) + return -ENOMEM; + + 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); |