drivers/char/resetswitch.c

   1 /***************************************************************************/
   2
   3 /*
   4  *      linux/drivers/char/resetswitch.c
   5  *
   6  *      Basic driver to support the Moxart software reset button.
   7  *
   8  *      Jimmy_chen@moxa.com.tw
   9  */
  10
  11 /***************************************************************************/
  12
  13 #if 1   // add by Victor Yu. 02-09-2007
  14 #include <linux/version.h>
  15 #endif
  16 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,12) // add by Victor Yu. 02-09-2007
  17 #include <linux/config.h>
  18 #endif
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include <linux/sched.h>
  22 #include <linux/param.h>
  23 #include <linux/init.h>
  24 #include <asm/irq.h>
  25 #include <asm/traps.h>
  26 #include <linux/delay.h>
  27 #include <linux/sched.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/timer.h>
  30 #include <linux/syscalls.h>
  31 #include <linux/reboot.h>
  32 #include <asm/uaccess.h>
  33 #include <asm/io.h>
  34 #include <asm/arch/moxa.h>
  35 #include <asm/arch/gpio.h>
  36
  37 #define RESET_POLL_TIME                 (HZ/5)
  38 #define RESET_TIMEOUT                   (HZ * 5)
  39
  40 #define PIO(x)                          1<<x
  41
  42 #if defined(CONFIG_ARCH_W311_TEST)      // add by VIctor Yu. 07-05-2008
  43 #define RESET_IO                        PIO(23)
  44 #define LED_READY                       PIO(4)
  45 #else
  46 #define RESET_IO                        PIO(25)
  47 #define LED_READY                       PIO(27)
  48 #endif
  49
  50 struct work_struct              resetqueue;
  51 static struct timer_list        resettimer;
  52 static spinlock_t               resetlock=SPIN_LOCK_UNLOCKED;
  53 static unsigned long            endresettime, intervaltime;
  54 static int                      ledonoffflag;
  55
  56 static void reset_to_default(void)
  57 {
  58         char *argv[3] , *envp[4] ;
  59
  60         envp[0] = "HOME=/" ;
  61         envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin" ;
  62         envp[2] = "TERM=console" ;
  63         envp[3] = NULL ;
  64
  65         argv[0] = "ldfactory" ;
  66         argv[1] = NULL ;
  67
  68         printk("reset to default\n") ;
  69         if(call_usermodehelper("/bin/ldfactory",argv,envp,0)==-1)
  70                 printk("set to default failure\n") ;
  71 }
  72
  73 static void reset_poll(unsigned long ingore)
  74 {
  75         spin_lock(&resetlock);
  76         del_timer(&resettimer);
  77         if ( !mcpu_gpio_get(RESET_IO) ) {
  78                 if ( endresettime == 0 ) {
  79                         endresettime = jiffies + RESET_TIMEOUT;
  80                         intervaltime = jiffies + HZ;
  81                 } else if ( time_after(jiffies, endresettime) ){
  82                         mcpu_gpio_set(LED_READY, MCPU_GPIO_HIGH);
  83                         schedule_work(&resetqueue);
  84                         goto poll_exit;
  85                 } else if ( time_after(jiffies, intervaltime) ) {
  86                         if ( ledonoffflag ) {
  87                                 ledonoffflag = 0;
  88                                 mcpu_gpio_set(LED_READY, MCPU_GPIO_HIGH);
  89                         } else {
  90                                 ledonoffflag = 1;
  91                                 mcpu_gpio_set(LED_READY, MCPU_GPIO_LOW);
  92                         }
  93                         intervaltime = jiffies + HZ;
  94                 }
  95         } else if ( endresettime ) {
  96                 endresettime = 0;
  97                 ledonoffflag = 1;
  98                 mcpu_gpio_set(LED_READY, MCPU_GPIO_LOW);
  99         }
 100         resettimer.function = reset_poll;
 101         resettimer.expires = jiffies + RESET_POLL_TIME;
 102         add_timer(&resettimer);
 103 poll_exit:
 104         spin_unlock(&resetlock);
 105 }
 106
 107 /***************************************************************************/
 108 static void __exit resetswitch_exit(void)
 109 {
 110         spin_lock(&resetlock);
 111         del_timer(&resettimer);
 112         spin_unlock(&resetlock);
 113 }
 114
 115 static int resetswitch_init(void)
 116 {
 117         // initialize the GPIO mode and directly
 118         mcpu_gpio_mp_set(RESET_IO|LED_READY);
 119         mcpu_gpio_inout(RESET_IO, MCPU_GPIO_INPUT);
 120         mcpu_gpio_inout(LED_READY, MCPU_GPIO_OUTPUT);
 121
 122         INIT_WORK(&resetqueue, reset_to_default, NULL);
 123         spin_lock(&resetlock);
 124         endresettime = 0;
 125         ledonoffflag = 1;
 126         init_timer(&resettimer);
 127         resettimer.function = reset_poll;
 128         resettimer.expires = jiffies + RESET_POLL_TIME;
 129         add_timer(&resettimer);
 130         spin_unlock(&resetlock);
 131
 132         return 0;
 133 }
 134
 135 module_init(resetswitch_init);
 136 module_exit(resetswitch_exit);
 137
 138 /***************************************************************************/