Better fix for quitting X hang. Interrupted mailbox reads are not som…

…ething we can reliably recover from, so down_interruptable is not a safe call.

arch/arm/mach-bcm2708/vcio.c

@@ -119,14 +119,10 @@ static int mbox_read(struct vc_mailbox *mbox, unsigned chan, uint32_t *data28)
 	if (mbox->magic != MBOX_MAGIC)
 		rc = -EINVAL;
 	else {
-		if (down_interruptible(&mbox->sema[chan]) == 0) {
-			*data28 = MBOX_DATA28(mbox->msg[chan]);
-			mbox->msg[chan] = 0;
-			rc = 0;
-		} else {
-			/* The wait was interrupted */
-			rc = -EINTR;
-		}
+		down(&mbox->sema[chan]);
+		*data28 = MBOX_DATA28(mbox->msg[chan]);
+		mbox->msg[chan] = 0;
+		rc = 0;
 	}
 	return rc;
 }

drivers/video/bcm2708_fb.c

@@ -222,9 +222,6 @@ static int bcm2708_fb_set_par(struct fb_info *info)
 	/* inform vc about new framebuffer */
 	bcm_mailbox_write(MBOX_CHAN_FB, fb->dma);
 
-	/* workaround occasional failure to read results. TODO: fix */
-	msleep(10);
-
 	/* wait for response */
 	bcm_mailbox_read(MBOX_CHAN_FB, &val);