HID: usbhid: fix error handling of not enough bandwidth
In case IO cannot be started because there is a lack of bandwidth
on the bus, it makes no sense to reset the device. If IO is requested
because the device is opened, user space should be notified with
an error right away. If the lack of bandwidth arises later, for
example after resume, there's no other choice but to retry in the
hope that bandwidth will be freed.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 5bf91db..c1a1dd5 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -86,8 +86,13 @@
!test_bit(HID_REPORTED_IDLE, &usbhid->iofl) &&
!test_and_set_bit(HID_IN_RUNNING, &usbhid->iofl)) {
rc = usb_submit_urb(usbhid->urbin, GFP_ATOMIC);
- if (rc != 0)
+ if (rc != 0) {
clear_bit(HID_IN_RUNNING, &usbhid->iofl);
+ if (rc == -ENOSPC)
+ set_bit(HID_NO_BANDWIDTH, &usbhid->iofl);
+ } else {
+ clear_bit(HID_NO_BANDWIDTH, &usbhid->iofl);
+ }
}
spin_unlock_irqrestore(&usbhid->lock, flags);
return rc;
@@ -173,8 +178,10 @@
if (time_after(jiffies, usbhid->stop_retry)) {
- /* Retries failed, so do a port reset */
- if (!test_and_set_bit(HID_RESET_PENDING, &usbhid->iofl)) {
+ /* Retries failed, so do a port reset unless we lack bandwidth*/
+ if (test_bit(HID_NO_BANDWIDTH, &usbhid->iofl)
+ && !test_and_set_bit(HID_RESET_PENDING, &usbhid->iofl)) {
+
schedule_work(&usbhid->reset_work);
goto done;
}
@@ -700,7 +707,7 @@
int usbhid_open(struct hid_device *hid)
{
struct usbhid_device *usbhid = hid->driver_data;
- int res;
+ int res = 0;
mutex_lock(&hid_open_mut);
if (!hid->open++) {
@@ -708,17 +715,27 @@
/* the device must be awake to reliably request remote wakeup */
if (res < 0) {
hid->open--;
- mutex_unlock(&hid_open_mut);
- return -EIO;
+ res = -EIO;
+ goto done;
}
usbhid->intf->needs_remote_wakeup = 1;
- if (hid_start_in(hid))
- hid_io_error(hid);
-
+ res = hid_start_in(hid);
+ if (res) {
+ if (res != -ENOSPC) {
+ hid_io_error(hid);
+ res = 0;
+ } else {
+ /* no use opening if resources are insufficient */
+ hid->open--;
+ res = -EBUSY;
+ usbhid->intf->needs_remote_wakeup = 0;
+ }
+ }
usb_autopm_put_interface(usbhid->intf);
}
+done:
mutex_unlock(&hid_open_mut);
- return 0;
+ return res;
}
void usbhid_close(struct hid_device *hid)
diff --git a/drivers/hid/usbhid/usbhid.h b/drivers/hid/usbhid/usbhid.h
index cb8f703..1883d7b 100644
--- a/drivers/hid/usbhid/usbhid.h
+++ b/drivers/hid/usbhid/usbhid.h
@@ -55,6 +55,7 @@
#define HID_STARTED 8
#define HID_REPORTED_IDLE 9
#define HID_KEYS_PRESSED 10
+#define HID_NO_BANDWIDTH 11
/*
* USB-specific HID struct, to be pointed to
