diff options
| -rw-r--r-- | drivers/nfc/port100.c | 42 |
1 files changed, 37 insertions, 5 deletions
diff --git a/drivers/nfc/port100.c b/drivers/nfc/port100.c index 14a3cc2d0fd6..909e3df2c16a 100644 --- a/drivers/nfc/port100.c +++ b/drivers/nfc/port100.c @@ -456,6 +456,12 @@ struct port100 { struct urb *out_urb; struct urb *in_urb; + /* This mutex protects the out_urb and avoids to submit a new command + * through port100_send_frame_async() while the previous one is being + * canceled through port100_abort_cmd(). + */ + struct mutex out_urb_lock; + struct work_struct cmd_complete_work; u8 cmd_type; @@ -464,6 +470,8 @@ struct port100 { * for any queuing/locking mechanism at driver level. */ struct port100_cmd *cmd; + + bool cmd_cancel; }; struct port100_cmd { @@ -718,10 +726,22 @@ static int port100_send_ack(struct port100 *dev) { int rc; + mutex_lock(&dev->out_urb_lock); + + usb_kill_urb(dev->out_urb); + dev->out_urb->transfer_buffer = ack_frame; dev->out_urb->transfer_buffer_length = sizeof(ack_frame); rc = usb_submit_urb(dev->out_urb, GFP_KERNEL); + /* Set the cmd_cancel flag only if the URB has been successfully + * submitted. It will be reset by the out URB completion callback + * port100_send_complete(). + */ + dev->cmd_cancel = !rc; + + mutex_unlock(&dev->out_urb_lock); + return rc; } @@ -730,6 +750,16 @@ static int port100_send_frame_async(struct port100 *dev, struct sk_buff *out, { int rc; + mutex_lock(&dev->out_urb_lock); + + /* A command cancel frame as been sent through dev->out_urb. Don't try + * to submit a new one. + */ + if (dev->cmd_cancel) { + rc = -EAGAIN; + goto exit; + } + dev->out_urb->transfer_buffer = out->data; dev->out_urb->transfer_buffer_length = out->len; @@ -741,16 +771,15 @@ static int port100_send_frame_async(struct port100 *dev, struct sk_buff *out, rc = usb_submit_urb(dev->out_urb, GFP_KERNEL); if (rc) - return rc; + goto exit; rc = port100_submit_urb_for_ack(dev, GFP_KERNEL); if (rc) - goto error; + usb_unlink_urb(dev->out_urb); - return 0; +exit: + mutex_unlock(&dev->out_urb_lock); -error: - usb_unlink_urb(dev->out_urb); return rc; } @@ -892,6 +921,8 @@ static void port100_send_complete(struct urb *urb) { struct port100 *dev = urb->context; + dev->cmd_cancel = false; + switch (urb->status) { case 0: break; /* success */ @@ -1455,6 +1486,7 @@ static int port100_probe(struct usb_interface *interface, if (!dev) return -ENOMEM; + mutex_init(&dev->out_urb_lock); dev->udev = usb_get_dev(interface_to_usbdev(interface)); dev->interface = interface; usb_set_intfdata(interface, dev); |