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authorTakashi Iwai <tiwai@suse.de>2017-10-04 16:15:59 +0200
committerTakashi Iwai <tiwai@suse.de>2017-10-11 15:14:32 +0200
commite901b9873876ca30a09253731bd3a6b00c44b5b0 (patch)
tree9d9c10973fdf8162552f9428eec373137f44f353 /drivers
parent8a5776a5f49812d29fe4b2d0a2d71675c3facf3f (diff)
usb: core: Add a helper function to check the validity of EP type in URB
This patch adds a new helper function to perform a sanity check of the given URB to see whether it contains a valid endpoint. It's a light- weight version of what usb_submit_urb() does, but without the kernel warning followed by the stack trace, just returns an error code. Especially for a driver that doesn't parse the descriptor but fills the URB with the fixed endpoint (e.g. some quirks for non-compliant devices), this kind of check is preferable at the probe phase before actually submitting the urb. Tested-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/usb/core/urb.c30
1 files changed, 26 insertions, 4 deletions
diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
index 47903d510955..8b800e34407b 100644
--- a/drivers/usb/core/urb.c
+++ b/drivers/usb/core/urb.c
@@ -187,6 +187,31 @@ EXPORT_SYMBOL_GPL(usb_unanchor_urb);
/*-------------------------------------------------------------------*/
+static const int pipetypes[4] = {
+ PIPE_CONTROL, PIPE_ISOCHRONOUS, PIPE_BULK, PIPE_INTERRUPT
+};
+
+/**
+ * usb_urb_ep_type_check - sanity check of endpoint in the given urb
+ * @urb: urb to be checked
+ *
+ * This performs a light-weight sanity check for the endpoint in the
+ * given urb. It returns 0 if the urb contains a valid endpoint, otherwise
+ * a negative error code.
+ */
+int usb_urb_ep_type_check(const struct urb *urb)
+{
+ const struct usb_host_endpoint *ep;
+
+ ep = usb_pipe_endpoint(urb->dev, urb->pipe);
+ if (!ep)
+ return -EINVAL;
+ if (usb_pipetype(urb->pipe) != pipetypes[usb_endpoint_type(&ep->desc)])
+ return -EINVAL;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usb_urb_ep_type_check);
+
/**
* usb_submit_urb - issue an asynchronous transfer request for an endpoint
* @urb: pointer to the urb describing the request
@@ -326,9 +351,6 @@ EXPORT_SYMBOL_GPL(usb_unanchor_urb);
*/
int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
{
- static int pipetypes[4] = {
- PIPE_CONTROL, PIPE_ISOCHRONOUS, PIPE_BULK, PIPE_INTERRUPT
- };
int xfertype, max;
struct usb_device *dev;
struct usb_host_endpoint *ep;
@@ -444,7 +466,7 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
*/
/* Check that the pipe's type matches the endpoint's type */
- if (usb_pipetype(urb->pipe) != pipetypes[xfertype])
+ if (usb_urb_ep_type_check(urb))
dev_WARN(&dev->dev, "BOGUS urb xfer, pipe %x != type %x\n",
usb_pipetype(urb->pipe), pipetypes[xfertype]);