target/linux/atheros/files-2.6.26/arch/mips/atheros/reset.c

   1 #include <linux/module.h>
   2 #include <linux/timer.h>
   3 #include <linux/interrupt.h>
   4 #include <linux/kobject.h>
   5 #include <linux/workqueue.h>
   6 #include <linux/skbuff.h>
   7 #include <linux/netlink.h>
   8 #include <net/sock.h>
   9 #include <asm/uaccess.h>
  10 #include <ar531x.h>
  11
  12 #define AR531X_RESET_GPIO_IRQ   (AR531X_GPIO_IRQ(bcfg->resetConfigGpio))
  13
  14 struct event_t {
  15         struct work_struct wq;
  16         int set;
  17         unsigned long jiffies;
  18 };
  19
  20 static struct ar531x_boarddata *bcfg;
  21 static struct timer_list rst_button_timer;
  22
  23 extern struct sock *uevent_sock;
  24 extern u64 uevent_next_seqnum(void);
  25 static unsigned long seen;
  26
  27 static inline void add_msg(struct sk_buff *skb, char *msg)
  28 {
  29         char *scratch;
  30         scratch = skb_put(skb, strlen(msg) + 1);
  31         sprintf(scratch, msg);
  32 }
  33
  34 static void hotplug_button(struct work_struct *wq)
  35 {
  36         struct sk_buff *skb;
  37         struct event_t *event;
  38         size_t len;
  39         char *scratch, *s;
  40         char buf[128];
  41
  42         event = container_of(wq, struct event_t, wq);
  43         if (!uevent_sock)
  44                 goto done;
  45
  46         /* allocate message with the maximum possible size */
  47         s = event->set ? "pressed" : "released";
  48         len = strlen(s) + 2;
  49         skb = alloc_skb(len + 2048, GFP_KERNEL);
  50         if (!skb)
  51                 goto done;
  52
  53         /* add header */
  54         scratch = skb_put(skb, len);
  55         sprintf(scratch, "%s@",s);
  56
  57         /* copy keys to our continuous event payload buffer */
  58         add_msg(skb, "HOME=/");
  59         add_msg(skb, "PATH=/sbin:/bin:/usr/sbin:/usr/bin");
  60         add_msg(skb, "SUBSYSTEM=button");
  61         add_msg(skb, "BUTTON=reset");
  62         add_msg(skb, (event->set ? "ACTION=pressed" : "ACTION=released"));
  63         sprintf(buf, "SEEN=%ld", (event->jiffies - seen)/HZ);
  64         add_msg(skb, buf);
  65         snprintf(buf, 128, "SEQNUM=%llu", uevent_next_seqnum());
  66         add_msg(skb, buf);
  67
  68         NETLINK_CB(skb).dst_group = 1;
  69         netlink_broadcast(uevent_sock, skb, 0, 1, GFP_KERNEL);
  70
  71 done:
  72         kfree(event);
  73 }
  74
  75 static int no_release_workaround = 1;
  76
  77 static void
  78 reset_button_poll(unsigned long unused)
  79 {
  80         struct event_t *event;
  81         int gpio = ~0;
  82
  83         if(!no_release_workaround)
  84                 return;
  85
  86         DO_AR5315(gpio = sysRegRead(AR5315_GPIO_DI);)
  87     gpio &= 1 << (AR531X_RESET_GPIO_IRQ - AR531X_GPIO_IRQ_BASE);
  88         if(gpio)
  89         {
  90                 rst_button_timer.expires = jiffies + (HZ / 4);
  91                 add_timer(&rst_button_timer);
  92         } else {
  93                 event = (struct event_t *) kzalloc(sizeof(struct event_t), GFP_ATOMIC);
  94                 if (!event)
  95                 {
  96                         printk("Could not alloc hotplug event\n");
  97                         return;
  98                 }
  99                 event->set = 0;
 100                 event->jiffies = jiffies;
 101                 INIT_WORK(&event->wq, (void *)(void *)hotplug_button);
 102                 schedule_work(&event->wq);
 103         }
 104 }
 105
 106 static irqreturn_t button_handler(int irq, void *dev_id)
 107 {
 108         static int pressed = 0;
 109         struct event_t *event;
 110         u32 gpio = ~0;
 111
 112         event = (struct event_t *) kzalloc(sizeof(struct event_t), GFP_ATOMIC);
 113         if (!event)
 114                 return IRQ_NONE;
 115
 116         pressed = !pressed;
 117
 118         DO_AR5315(gpio = sysRegRead(AR5315_GPIO_DI);)
 119         gpio &= 1 << (irq - AR531X_GPIO_IRQ_BASE);
 120
 121         event->set = gpio;
 122         if(!event->set)
 123                 no_release_workaround = 0;
 124
 125         event->jiffies = jiffies;
 126
 127         INIT_WORK(&event->wq, (void *)(void *)hotplug_button);
 128         schedule_work(&event->wq);
 129
 130         seen = jiffies;
 131         if(event->set && no_release_workaround)
 132                 mod_timer(&rst_button_timer, jiffies + (HZ / 4));
 133
 134         return IRQ_HANDLED;
 135 }
 136
 137 void ar531x_disable_reset_button(void)
 138 {
 139         disable_irq(AR531X_RESET_GPIO_IRQ);
 140 }
 141
 142 EXPORT_SYMBOL(ar531x_disable_reset_button);
 143
 144 int __init ar531x_init_reset(void)
 145 {
 146         bcfg = (struct ar531x_boarddata *) board_config;
 147
 148         seen = jiffies;
 149
 150         init_timer(&rst_button_timer);
 151         rst_button_timer.function = reset_button_poll;
 152         rst_button_timer.expires = jiffies + HZ / 50;
 153         add_timer(&rst_button_timer);
 154
 155         request_irq(AR531X_RESET_GPIO_IRQ, &button_handler, IRQF_SAMPLE_RANDOM, "ar531x_reset", NULL);
 156
 157         return 0;
 158 }
 159
 160
 161
 162 module_init(ar531x_init_reset);