V4L/DVB (12938): SAA7164: Increase the firmware command timeout to avoid firmware errors.

The firmware typically responds in < 50ms and, via the interrupts and
deferred work queue the caller (blocked in the driver) is signalled very
efficiently. In a highly stressed system this can take many multiples
of seconds. So, we need a larger maximum timeout for busy systems.

Signed-off-by: Steven Toth <stoth@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 7 insertions, 1 deletions

diff --git a/drivers/media/video/saa7164/saa7164-cmd.c b/drivers/media/video/saa7164/saa7164-cmd.c
index 171ef116f078..cd3af4d4364f 100644
--- a/drivers/media/video/saa7164/saa7164-cmd.c
+++ b/drivers/media/video/saa7164/saa7164-cmd.c
@@ -234,6 +234,12 @@ int saa7164_cmd_wait(struct saa7164_dev *dev, u8 seqno)
                                 __func__, seqno, dev->cmds[seqno].signalled);
 
                         /* Wait for signalled to be flagged or timeout */
+                        /* In a highly stressed system this can easily extend
+                         * into multiple seconds before the deferred worker
+                         * is scheduled, and we're woken up via signal.
+                         * We typically are signalled in < 50ms but it can
+                         * take MUCH longer.
+                         */
                         wait_event_timeout(*q, dev->cmds[seqno].signalled, (HZ * waitsecs));
                         r = time_before(jiffies, stamp + (HZ * waitsecs));
                         if (r)
diff --git a/drivers/media/video/saa7164/saa7164-core.c b/drivers/media/video/saa7164/saa7164-core.c
index 06dab7cbcaac..da6dbe579624 100644
--- a/drivers/media/video/saa7164/saa7164-core.c
+++ b/drivers/media/video/saa7164/saa7164-core.c
@@ -49,7 +49,7 @@ unsigned int debug;
 module_param(debug, int, 0644);
 MODULE_PARM_DESC(debug, "enable debug messages");
 
-unsigned int waitsecs = 1;
+unsigned int waitsecs = 10;
 module_param(waitsecs, int, 0644);
 MODULE_PARM_DESC(debug, "timeout on firmware messages");