Merge tag 'for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/kishon/linux...

[deliverable/linux.git] / drivers / usb / class / cdc-acm.c

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 683617714e7cf852fdf3fc2d4ec8590ab6d1a114..3e15add665e236f2ef15bd1a9858dd9eabcb0c96 100644 (file)
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -360,7 +360,7 @@ static void acm_ctrl_irq(struct urb *urb)
        }
 exit:
        retval = usb_submit_urb(urb, GFP_ATOMIC);
-       if (retval)
+       if (retval && retval != -EPERM)
                dev_err(&acm->control->dev, "%s - usb_submit_urb failed: %d\n",
                                                        __func__, retval);
 }
@@ -417,25 +417,33 @@ static void acm_read_bulk_callback(struct urb *urb)
        struct acm_rb *rb = urb->context;
        struct acm *acm = rb->instance;
        unsigned long flags;
+       int status = urb->status;
 
        dev_vdbg(&acm->data->dev, "%s - urb %d, len %d\n", __func__,
                                        rb->index, urb->actual_length);
-       set_bit(rb->index, &acm->read_urbs_free);
 
        if (!acm->dev) {
+               set_bit(rb->index, &acm->read_urbs_free);
                dev_dbg(&acm->data->dev, "%s - disconnected\n", __func__);
                return;
        }
 
-       if (urb->status) {
+       if (status) {
+               set_bit(rb->index, &acm->read_urbs_free);
                dev_dbg(&acm->data->dev, "%s - non-zero urb status: %d\n",
-                                                       __func__, urb->status);
+                                                       __func__, status);
                return;
        }
 
        usb_mark_last_busy(acm->dev);
 
        acm_process_read_urb(acm, urb);
+       /*
+        * Unthrottle may run on another CPU which needs to see events
+        * in the same order. Submission has an implict barrier
+        */
+       smp_mb__before_atomic();
+       set_bit(rb->index, &acm->read_urbs_free);
 
        /* throttle device if requested by tty */
        spin_lock_irqsave(&acm->read_lock, flags);
@@ -454,13 +462,14 @@ static void acm_write_bulk(struct urb *urb)
        struct acm_wb *wb = urb->context;
        struct acm *acm = wb->instance;
        unsigned long flags;
+       int status = urb->status;
 
-       if (urb->status || (urb->actual_length != urb->transfer_buffer_length))
+       if (status || (urb->actual_length != urb->transfer_buffer_length))
                dev_vdbg(&acm->data->dev, "%s - len %d/%d, status %d\n",
                        __func__,
                        urb->actual_length,
                        urb->transfer_buffer_length,
-                       urb->status);
+                       status);
 
        spin_lock_irqsave(&acm->write_lock, flags);
        acm_write_done(acm, wb);