Re: [PATCH] xen,input: try to read screen resolution for xen-kbdfront

From: Dmitry Torokhov
Date: Tue Jan 24 2017 - 13:48:03 EST


On Tue, Jan 24, 2017 at 01:09:55PM +0100, Juergen Gross wrote:
> Instead of using the default resolution of 800*600 for the pointing
> device of xen-kbdfront try to read the resolution of the (virtual)
> framebuffer device. Use the default as fallback only.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> ---
> drivers/input/misc/xen-kbdfront.c | 15 ++++++++++++---
> 1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c
> index 3900875..0032c81 100644
> --- a/drivers/input/misc/xen-kbdfront.c
> +++ b/drivers/input/misc/xen-kbdfront.c
> @@ -16,6 +16,7 @@
> #include <linux/kernel.h>
> #include <linux/errno.h>
> #include <linux/module.h>
> +#include <linux/fb.h>
> #include <linux/input.h>
> #include <linux/slab.h>
>
> @@ -108,10 +109,11 @@ static irqreturn_t input_handler(int rq, void *dev_id)
> static int xenkbd_probe(struct xenbus_device *dev,
> const struct xenbus_device_id *id)
> {
> - int ret, i;
> + int ret, i, width, height;
> unsigned int abs;
> struct xenkbd_info *info;
> struct input_dev *kbd, *ptr;
> + struct fb_info *fb0;
>
> info = kzalloc(sizeof(*info), GFP_KERNEL);
> if (!info) {
> @@ -173,9 +175,16 @@ static int xenkbd_probe(struct xenbus_device *dev,
> ptr->id.product = 0xfffe;
>
> if (abs) {
> + width = XENFB_WIDTH;
> + height = XENFB_HEIGHT;
> + fb0 = registered_fb[0];

This will break if !CONFIG_FBi I think. While i see that xen.config has
it on I wonder if it is still possible to turn it off (either randconfig
or intentionally).

Thanks.

--
Dmitry