On Wed, Sep 02, 2020 at 01:01:03PM +0200, Greg Kroah-Hartman wrote:
> snd_usb_pipe_sanity_check() is a great function, so let's move it into
> the USB core so that other parts of the kernel, including the USB core,
> can call it.
>
> Name it usb_pipe_type_check() to match the existing
> usb_urb_ep_type_check() call, which now uses this function.
>
> Cc: Jaroslav Kysela <perex@xxxxxxxx>
> Cc: Takashi Iwai <tiwai@xxxxxxxx>
> Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>
> Cc: Eli Billauer <eli.billauer@xxxxxxxxx>
> Cc: Emiliano Ingrassia <ingrassia@xxxxxxxxxxxxxx>
> Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> Cc: Alexander Tsoy <alexander@xxxxxxx>
> Cc: "Geoffrey D. Bennett" <g@xxxxx>
> Cc: Jussi Laako <jussi@xxxxxxxxxxxxx>
> Cc: Nick Kossifidis <mickflemm@xxxxxxxxx>
> Cc: Dmitry Panchenko <dmitry@xxxxxxxxxxxx>
> Cc: Chris Wulff <crwulff@xxxxxxxxx>
> Cc: Jesus Ramos <jesus-ramos@xxxxxxxx>
> Cc: linux-usb@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Cc: alsa-devel@xxxxxxxxxxxxxxxx
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
> diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
> index 27e83e55a590..45bc2914c1ba 100644
> --- a/drivers/usb/core/urb.c
> +++ b/drivers/usb/core/urb.c
> @@ -192,24 +192,39 @@ static const int pipetypes[4] = {
> };
>
> /**
> - * usb_urb_ep_type_check - sanity check of endpoint in the given urb
> - * @urb: urb to be checked
> + * usb_pipe_type_check - sanity check of a specific pipe for a usb device
> + * @dev: struct usb_device to be checked
> + * @pipe: pipe to check
> *
> * 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.
> + * given usb device. It returns 0 if the pipe is a valid for the specific usb
-----------------------------------------------------^
Typo.
> + * device, otherwise a negative error code.
> */
> -int usb_urb_ep_type_check(const struct urb *urb)
> +int usb_pipe_type_check(struct usb_device *dev, unsigned int pipe)
> {
> const struct usb_host_endpoint *ep;
>
> - ep = usb_pipe_endpoint(urb->dev, urb->pipe);
> + ep = usb_pipe_endpoint(dev, pipe);
> if (!ep)
> return -EINVAL;
> - if (usb_pipetype(urb->pipe) != pipetypes[usb_endpoint_type(&ep->desc)])
> + if (usb_pipetype(pipe) != pipetypes[usb_endpoint_type(&ep->desc)])
> return -EINVAL;
> return 0;
> }
> +EXPORT_SYMBOL_GPL(usb_pipe_type_check);
> +
> +/**
> + * 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)
> +{
> + return usb_pipe_type_check(urb->dev, urb->pipe);
> +}
> EXPORT_SYMBOL_GPL(usb_urb_ep_type_check);
Since this routine is used in only one place in the entire kernel, you
might as well inline the code there and get rid of the function
entirely.
> diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
> index abf99b814a0f..fc3aab04a0bc 100644
> --- a/sound/usb/quirks.c
> +++ b/sound/usb/quirks.c
> @@ -846,7 +846,7 @@ static int snd_usb_accessmusic_boot_quirk(struct usb_device *dev)
> static const u8 seq[] = { 0x4e, 0x73, 0x52, 0x01 };
> void *buf;
>
> - if (snd_usb_pipe_sanity_check(dev, usb_sndintpipe(dev, 0x05)))
> + if (usb_pipe_type_check(dev, usb_sndintpipe(dev, 0x05)))
> return -EINVAL;
> buf = kmemdup(seq, ARRAY_SIZE(seq), GFP_KERNEL);
> if (!buf)
> @@ -875,7 +875,7 @@ static int snd_usb_nativeinstruments_boot_quirk(struct usb_device *dev)
> {
> int ret;
>
> - if (snd_usb_pipe_sanity_check(dev, usb_sndctrlpipe(dev, 0)))
> + if (usb_pipe_type_check(dev, usb_sndctrlpipe(dev, 0)))
> return -EINVAL;
In a few places here this check is completely unnecessary. All it does
is verify that the device does have an endpoint 0 and the the type of
the endpoint matches the type of the pipe. Well, every USB device
always has an endpoint 0, and it is always a bidirectional control
endpoint. Therefore a simple static check is all you need: There's no
point calling usb_pipe_type_check() when the pipe is of the form
usb_{snd|rcv}ctrlpipe(dev, 0).
In short, this check should be removed completely; it does nothing.
> ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
> 0xaf, USB_TYPE_VENDOR | USB_RECIP_DEVICE,
> @@ -984,7 +984,7 @@ static int snd_usb_axefx3_boot_quirk(struct usb_device *dev)
>
> dev_dbg(&dev->dev, "Waiting for Axe-Fx III to boot up...\n");
>
> - if (snd_usb_pipe_sanity_check(dev, usb_sndctrlpipe(dev, 0)))
> + if (usb_pipe_type_check(dev, usb_sndctrlpipe(dev, 0)))
Same for this check.
> return -EINVAL;
> /* If the Axe-Fx III has not fully booted, it will timeout when trying
> * to enable the audio streaming interface. A more generous timeout is
> @@ -1018,7 +1018,7 @@ static int snd_usb_motu_microbookii_communicate(struct usb_device *dev, u8 *buf,
> {
> int err, actual_length;
>
> - if (snd_usb_pipe_sanity_check(dev, usb_sndintpipe(dev, 0x01)))
> + if (usb_pipe_type_check(dev, usb_sndintpipe(dev, 0x01)))
> return -EINVAL;
> err = usb_interrupt_msg(dev, usb_sndintpipe(dev, 0x01), buf, *length,
> &actual_length, 1000);
> @@ -1030,7 +1030,7 @@ static int snd_usb_motu_microbookii_communicate(struct usb_device *dev, u8 *buf,
>
> memset(buf, 0, buf_size);
>
> - if (snd_usb_pipe_sanity_check(dev, usb_rcvintpipe(dev, 0x82)))
> + if (usb_pipe_type_check(dev, usb_rcvintpipe(dev, 0x82)))
> return -EINVAL;
> err = usb_interrupt_msg(dev, usb_rcvintpipe(dev, 0x82), buf, buf_size,
> &actual_length, 1000);
> @@ -1117,7 +1117,7 @@ static int snd_usb_motu_m_series_boot_quirk(struct usb_device *dev)
> {
> int ret;
>
> - if (snd_usb_pipe_sanity_check(dev, usb_sndctrlpipe(dev, 0)))
> + if (usb_pipe_type_check(dev, usb_sndctrlpipe(dev, 0)))
And this one.
> return -EINVAL;
> ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
> 1, USB_TYPE_VENDOR | USB_RECIP_DEVICE,
Alan Stern
