From: Jason Gerecke Date: Thu, 21 May 2015 17:44:31 +0000 (-0700) Subject: HID: wacom: Have wacom_{get,set}_report retry on -EAGAIN, not -EPIPE X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=aef3156d7;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git HID: wacom: Have wacom_{get,set}_report retry on -EAGAIN, not -EPIPE Retrying on -EPIPE makes very little sense since this typically indicates a problem that will not just disappear on its own. For instance, the USB documentation states that it will be sent if the endpoint is stalled or the device has disconnected. Instead, we should retry if -EAGAIN is received since this indicates a temporary error condition such as a busy bus. In addition to adjusting the conditions we retry under, we also log an error on failure so that we can be aware of what's going on. Signed-off-by: Jason Gerecke Reviewed-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c index 7abf52caa8d8..109312f9d3de 100644 --- a/drivers/hid/wacom_sys.c +++ b/drivers/hid/wacom_sys.c @@ -35,7 +35,11 @@ static int wacom_get_report(struct hid_device *hdev, u8 type, u8 *buf, do { retval = hid_hw_raw_request(hdev, buf[0], buf, size, type, HID_REQ_GET_REPORT); - } while ((retval == -ETIMEDOUT || retval == -EPIPE) && --retries); + } while ((retval == -ETIMEDOUT || retval == -EAGAIN) && --retries); + + if (retval < 0) + hid_err(hdev, "wacom_get_report: ran out of retries " + "(last error = %d)\n", retval); return retval; } @@ -48,7 +52,11 @@ static int wacom_set_report(struct hid_device *hdev, u8 type, u8 *buf, do { retval = hid_hw_raw_request(hdev, buf[0], buf, size, type, HID_REQ_SET_REPORT); - } while ((retval == -ETIMEDOUT || retval == -EPIPE) && --retries); + } while ((retval == -ETIMEDOUT || retval == -EAGAIN) && --retries); + + if (retval < 0) + hid_err(hdev, "wacom_set_report: ran out of retries " + "(last error = %d)\n", retval); return retval; }