Re: [PATCH] input: pxrc - do not store USB device in private struct

From: Dmitry Torokhov
Date: Mon Jul 23 2018 - 22:38:14 EST


Hi Marcus,

On Mon, Jul 16, 2018 at 04:40:14PM +0200, Marcus Folkesson wrote:
> The USB device is only needed during setup, so put it back after
> initialization and do not store it in our private struct.
>
> Also, the USB device is a parent of USB interface so our driver
> model rules ensure that USB device should not disappear while
> interface device is still there.
> So not keep a refcount on the device is safe.
>
> Reported-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>
> Signed-off-by: Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
> ---
> drivers/input/joystick/pxrc.c | 22 ++++++++++++----------
> 1 file changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/input/joystick/pxrc.c b/drivers/input/joystick/pxrc.c
> index 07a0dbd3ced2..46a7acb747bf 100644
> --- a/drivers/input/joystick/pxrc.c
> +++ b/drivers/input/joystick/pxrc.c
...

> @@ -204,23 +204,25 @@ static int pxrc_probe(struct usb_interface *intf,
> return -ENOMEM;
>
> mutex_init(&pxrc->pm_mutex);
> - pxrc->udev = usb_get_dev(interface_to_usbdev(intf));
> + udev = usb_get_dev(interface_to_usbdev(intf));

There is really no need to "get" device for the probe duration, or in
general, when you are not storing the reference to it.

I posted series with an updated version of this patch plus couple more
cleanups/fixes, and would appreciate if you could give it a spin.

Thanks.

--
Dmitry