From e901b9873876ca30a09253731bd3a6b00c44b5b0 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 4 Oct 2017 16:15:59 +0200 Subject: 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 Acked-by: Greg Kroah-Hartman Signed-off-by: Takashi Iwai --- drivers/usb/core/urb.c | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-) (limited to 'drivers/usb') 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]); -- cgit