[3.12-rc1] USB: input: cm109.c: Convert high volume dev_err() to dev_err_ratelimited()

Commit Message

Dmitry Torokhov Sept. 19, 2013, 9:52 p.m. UTC

Hi Tim,

On Tue, Sep 10, 2013 at 10:23:13AM -0600, Tim Gardner wrote:
> BugLink: http://bugs.launchpad.net/bugs/1222850
> 
> This input device can get into a state that produces a high
> volume of device status errors. Attempt to throttle these
> error messages such that the kernel log is not flooded.
> 

Only 2 of these printks need to be rate-limited, as other failures are
fatal to the driver since it will not resubmit the IO.

Also I think we need to try and resubmit control URB to try and execute
buzzer command if previous one failed.

BTW, EPROTO/EILSEQ errors mentioned in the launchpad bug seem to relate
to timeout/CRC errors reported by the host controller, so it must indeed
be the extender that is misbehaving.

Thanks.

Comments

Tim Gardner Sept. 23, 2013, 5:51 p.m. UTC | #1

On 09/19/2013 02:52 PM, Dmitry Torokhov wrote:
> Hi Tim,
> 
> On Tue, Sep 10, 2013 at 10:23:13AM -0600, Tim Gardner wrote:
>> BugLink: http://bugs.launchpad.net/bugs/1222850
>>
>> This input device can get into a state that produces a high
>> volume of device status errors. Attempt to throttle these
>> error messages such that the kernel log is not flooded.
>>
> 
> Only 2 of these printks need to be rate-limited, as other failures are
> fatal to the driver since it will not resubmit the IO.
> 
> Also I think we need to try and resubmit control URB to try and execute
> buzzer command if previous one failed.
> 
> BTW, EPROTO/EILSEQ errors mentioned in the launchpad bug seem to relate
> to timeout/CRC errors reported by the host controller, so it must indeed
> be the extender that is misbehaving.
> 
> Thanks.
> 

Looks good to me.

rtg

Patch

diff --git a/drivers/input/misc/cm109.c b/drivers/input/misc/cm109.c
index 082684e..9365535 100644
--- a/drivers/input/misc/cm109.c
+++ b/drivers/input/misc/cm109.c
@@ -351,7 +351,9 @@  static void cm109_urb_irq_callback(struct urb *urb)
 	if (status) {
 		if (status == -ESHUTDOWN)
 			return;
-		dev_err(&dev->intf->dev, "%s: urb status %d\n", __func__, status);
+		dev_err_ratelimited(&dev->intf->dev, "%s: urb status %d\n",
+				    __func__, status);
+		goto out;
 	}
 
 	/* Special keys */
@@ -418,8 +420,12 @@  static void cm109_urb_ctl_callback(struct urb *urb)
 	     dev->ctl_data->byte[2],
 	     dev->ctl_data->byte[3]);
 
-	if (status)
-		dev_err(&dev->intf->dev, "%s: urb status %d\n", __func__, status);
+	if (status) {
+		if (status == -ESHUTDOWN)
+			return;
+		dev_err_ratelimited(&dev->intf->dev, "%s: urb status %d\n",
+				    __func__, status);
+	}
 
 	spin_lock(&dev->ctl_submit_lock);
 
@@ -427,7 +433,7 @@  static void cm109_urb_ctl_callback(struct urb *urb)
 
 	if (likely(!dev->shutdown)) {
 
-		if (dev->buzzer_pending) {
+		if (dev->buzzer_pending || status) {
 			dev->buzzer_pending = 0;
 			dev->ctl_urb_pending = 1;
 			cm109_submit_buzz_toggle(dev);