[ 67/72] [media] imon: dont wedge hardware after early callbacks

[Greg KH]

3.2-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jarod Wilson <jarod@xxxxxxxxxx>

commit 8791d63af0cf113725ae4cb8cba9492814c59a93 upstream.

This patch is just a minor update to one titled "imon: Input from ffdc
device type ignored" from Corinna Vinschen. An earlier patch to prevent
an oops when we got early callbacks also has the nasty side-effect of
wedging imon hardware, as we don't acknowledge the urb. Rework the check
slightly here to bypass processing the packet, as the driver isn't yet
fully initialized, but still acknowlege the urb and submit a new rx_urb.
Do this for both interfaces -- irrelevant for ffdc hardware, but
relevant for newer hardware, though newer hardware doesn't spew the
constant stream of data as soon as the hardware is initialized like the
older ffdc devices, so they'd be less likely to trigger this anyway...

Tested with both an ffdc device and an 0042 device.

Reported-by: Corinna Vinschen <vinschen@xxxxxxxxxx>
Signed-off-by: Jarod Wilson <jarod@xxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/media/rc/imon.c |   26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

--- a/drivers/media/rc/imon.c
+++ b/drivers/media/rc/imon.c
@@ -47,7 +47,7 @@
 #define MOD_AUTHOR	"Jarod Wilson <jarod@xxxxxxxxxxxx>"
 #define MOD_DESC	"Driver for SoundGraph iMON MultiMedia IR/Display"
 #define MOD_NAME	"imon"
-#define MOD_VERSION	"0.9.3"
+#define MOD_VERSION	"0.9.4"
 
 #define DISPLAY_MINOR_BASE	144
 #define DEVICE_NAME	"lcd%d"
@@ -1658,9 +1658,17 @@ static void usb_rx_callback_intf0(struct
 		return;
 
 	ictx = (struct imon_context *)urb->context;
-	if (!ictx || !ictx->dev_present_intf0)
+	if (!ictx)
 		return;
 
+	/*
+	 * if we get a callback before we're done configuring the hardware, we
+	 * can't yet process the data, as there's nowhere to send it, but we
+	 * still need to submit a new rx URB to avoid wedging the hardware
+	 */
+	if (!ictx->dev_present_intf0)
+		goto out;
+
 	switch (urb->status) {
 	case -ENOENT:		/* usbcore unlink successful! */
 		return;
@@ -1678,6 +1686,7 @@ static void usb_rx_callback_intf0(struct
 		break;
 	}
 
+out:
 	usb_submit_urb(ictx->rx_urb_intf0, GFP_ATOMIC);
 }
 
@@ -1690,9 +1699,17 @@ static void usb_rx_callback_intf1(struct
 		return;
 
 	ictx = (struct imon_context *)urb->context;
-	if (!ictx || !ictx->dev_present_intf1)
+	if (!ictx)
 		return;
 
+	/*
+	 * if we get a callback before we're done configuring the hardware, we
+	 * can't yet process the data, as there's nowhere to send it, but we
+	 * still need to submit a new rx URB to avoid wedging the hardware
+	 */
+	if (!ictx->dev_present_intf1)
+		goto out;
+
 	switch (urb->status) {
 	case -ENOENT:		/* usbcore unlink successful! */
 		return;
@@ -1710,6 +1727,7 @@ static void usb_rx_callback_intf1(struct
 		break;
 	}
 
+out:
 	usb_submit_urb(ictx->rx_urb_intf1, GFP_ATOMIC);
 }
 
@@ -2242,7 +2260,7 @@ find_endpoint_failed:
 	mutex_unlock(&ictx->lock);
 	usb_free_urb(rx_urb);
 rx_urb_alloc_failed:
-	dev_err(ictx->dev, "unable to initialize intf0, err %d\n", ret);
+	dev_err(ictx->dev, "unable to initialize intf1, err %d\n", ret);
 
 	return NULL;
 }


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/