b43: Add simple firmware watchdog

This adds a simple firmware watchdog for the opensource firmware.
This will check every 15 seconds, if the firmware zeroed out the watchdog
register. The firmware will do this in its eventloop.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 17 insertions, 0 deletions

diff --git a/drivers/net/wireless/b43/b43.h b/drivers/net/wireless/b43/b43.h
index 532365f5ecef..edcdfa366452 100644
--- a/drivers/net/wireless/b43/b43.h
+++ b/drivers/net/wireless/b43/b43.h
@@ -441,6 +441,8 @@ enum {
 #define B43_FWPANIC_DIE                 0 /* Firmware died. Don't auto-restart it. */
 #define B43_FWPANIC_RESTART             1 /* Firmware died. Schedule a controller reset. */
 
+/* The firmware register that contains the watchdog counter. */
+#define B43_WATCHDOG_REG                1
 
 /* Device specific rate values.
  * The actual values defined here are (rate_in_mbps * 2).
diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c
index 69272b9bdb69..c14d522d69e3 100644
--- a/drivers/net/wireless/b43/main.c
+++ b/drivers/net/wireless/b43/main.c
@@ -2807,6 +2807,21 @@ static void b43_periodic_every30sec(struct b43_wldev *dev)
 static void b43_periodic_every15sec(struct b43_wldev *dev)
 {
         struct b43_phy *phy = &dev->phy;
+        u16 wdr;
+
+        if (dev->fw.opensource) {
+                /* Check if the firmware is still alive.
+                 * It will reset the watchdog counter to 0 in its idle loop. */
+                wdr = b43_shm_read16(dev, B43_SHM_SCRATCH, B43_WATCHDOG_REG);
+                if (unlikely(wdr)) {
+                        b43err(dev->wl, "Firmware watchdog: The firmware died!\n");
+                        b43_controller_restart(dev, "Firmware watchdog");
+                        return;
+                } else {
+                        b43_shm_write16(dev, B43_SHM_SCRATCH,
+                                        B43_WATCHDOG_REG, 1);
+                }
+        }
 
         if (phy->type == B43_PHYTYPE_G) {
                 //TODO: update_aci_moving_average