ath6kl: add a timeout to ath6kl_hif_intr_bh_handler()

It's possible to busyloop forever in ath6kl_hif_intr_bh_handler(). Add
a check that it lasts only one second.
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath6kl/hif.c

@@ -485,6 +485,7 @@ static int proc_pending_irqs(struct ath6kl_device *dev, bool *done)
 int ath6kl_hif_intr_bh_handler(struct ath6kl *ar)
 {
 	struct ath6kl_device *dev = ar->htc_target->dev;
+	unsigned long timeout;
 	int status = 0;
 	bool done = false;
 
@@ -498,7 +499,8 @@ int ath6kl_hif_intr_bh_handler(struct ath6kl *ar)
 	 * IRQ processing is synchronous, interrupt status registers can be
 	 * re-read.
 	 */
-	while (!done) {
+	timeout = jiffies + msecs_to_jiffies(ATH6KL_HIF_COMMUNICATION_TIMEOUT);
+	while (time_before(jiffies, timeout) && !done) {
 		status = proc_pending_irqs(dev, &done);
 		if (status)
 			break;

drivers/net/wireless/ath/ath6kl/hif.h

@@ -69,6 +69,8 @@
 #define ATH6KL_MAX_TRANSFER_SIZE_PER_SCATTER      (16 * 1024)
 #define ATH6KL_SCATTER_REQS                       4
 
+#define ATH6KL_HIF_COMMUNICATION_TIMEOUT	1000
+
 struct bus_request {
 	struct list_head list;