Commit 9937c026 authored Jan 23, 2013 by Chris Bagwell Committed by Dmitry Torokhov Jan 23, 2013

Input: wacom - fix wacom_set_report retry logic



Logic sets a value and then reads it back to make sure it worked
and retries write on failures.  Since read and write share a buffer,
it needs to be set back up before writing though.

Issue is not seen a lot because 1) it doesn't need to retry for
a lot of tablets and 2) a lot of failures that need a retry are
from an -ETIMEDOUT and hopefully buffer is not touched in this case.

At least one user has shown logs with buffer being modified during
-ETIMEDOUT case with linux 3.7 kernel.

Signed-off-by: Chris Bagwell <chris@cnpbagwell.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

parent b666263b

drivers/input/tablet/wacom_sys.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -553,10 +553,10 @@ static int wacom_set_device_mode(struct usb_interface *intf, int report_id, int
		if (!rep_data)
		return error;

		do {
		rep_data[0] = report_id;
		rep_data[1] = mode;

		do {
		error = wacom_set_report(intf, WAC_HID_FEATURE_REPORT,
		report_id, rep_data, length, 1);
		if (error >= 0)