HID: usbhid: introduce timeout for stuck ctrl/out URBs

Some devices do not react to a control request (seen on APC UPS's) resulting in
a slow stream of messages, "generic-usb ... control queue full".  Therefore
request needs a timeout.

Cc: stable@kernel.org
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: David Fries <david@fries.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

2 files changed, 28 insertions, 2 deletions

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 54060741d45b..74bd3ca220d3 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -316,6 +316,7 @@ static int hid_submit_out(struct hid_device *hid)
                         err_hid("usb_submit_urb(out) failed");
                         return -1;
                 }
+                usbhid->last_out = jiffies;
         } else {
                 /*
                  * queue work to wake up the device.
@@ -377,6 +378,7 @@ static int hid_submit_ctrl(struct hid_device *hid)
                         err_hid("usb_submit_urb(ctrl) failed");
                         return -1;
                 }
+                usbhid->last_ctrl = jiffies;
         } else {
                 /*
                  * queue work to wake up the device.
@@ -512,9 +514,20 @@ static void __usbhid_submit_report(struct hid_device *hid, struct hid_report *re
                 usbhid->out[usbhid->outhead].report = report;
                 usbhid->outhead = head;
 
-                if (!test_and_set_bit(HID_OUT_RUNNING, &usbhid->iofl))
+                if (!test_and_set_bit(HID_OUT_RUNNING, &usbhid->iofl)) {
                         if (hid_submit_out(hid))
                                 clear_bit(HID_OUT_RUNNING, &usbhid->iofl);
+                } else {
+                        /*
+                         * the queue is known to run
+                         * but an earlier request may be stuck
+                         * we may need to time out
+                         * no race because this is called under
+                         * spinlock
+                         */
+                        if (time_after(jiffies, usbhid->last_out + HZ * 5))
+                                usb_unlink_urb(usbhid->urbout);
+                }
                 return;
         }
 
@@ -535,9 +548,20 @@ static void __usbhid_submit_report(struct hid_device *hid, struct hid_report *re
         usbhid->ctrl[usbhid->ctrlhead].dir = dir;
         usbhid->ctrlhead = head;
 
-        if (!test_and_set_bit(HID_CTRL_RUNNING, &usbhid->iofl))
+        if (!test_and_set_bit(HID_CTRL_RUNNING, &usbhid->iofl)) {
                 if (hid_submit_ctrl(hid))
                         clear_bit(HID_CTRL_RUNNING, &usbhid->iofl);
+        } else {
+                /*
+                 * the queue is known to run
+                 * but an earlier request may be stuck
+                 * we may need to time out
+                 * no race because this is called under
+                 * spinlock
+                 */
+                if (time_after(jiffies, usbhid->last_ctrl + HZ * 5))
+                        usb_unlink_urb(usbhid->urbctrl);
+        }
 }
 
 void usbhid_submit_report(struct hid_device *hid, struct hid_report *report, unsigned char dir)
diff --git a/drivers/hid/usbhid/usbhid.h b/drivers/hid/usbhid/usbhid.h
index 08f505ca2e3d..ec20400c7f29 100644
--- a/drivers/hid/usbhid/usbhid.h
+++ b/drivers/hid/usbhid/usbhid.h
@@ -80,12 +80,14 @@ struct usbhid_device {
         unsigned char ctrlhead, ctrltail;                               /* Control fifo head & tail */
         char *ctrlbuf;                                                  /* Control buffer */
         dma_addr_t ctrlbuf_dma;                                         /* Control buffer dma */
+        unsigned long last_ctrl;                                                /* record of last output for timeouts */
 
         struct urb *urbout;                                             /* Output URB */
         struct hid_output_fifo out[HID_CONTROL_FIFO_SIZE];              /* Output pipe fifo */
         unsigned char outhead, outtail;                                 /* Output pipe fifo head & tail */
         char *outbuf;                                                   /* Output buffer */
         dma_addr_t outbuf_dma;                                          /* Output buffer dma */
+        unsigned long last_out;                                                 /* record of last output for timeouts */
 
         spinlock_t lock;                                                /* fifo spinlock */
         unsigned long iofl;                                             /* I/O flags (CTRL_RUNNING, OUT_RUNNING) */