[PATCH 3/3] evdev: Implement axes swapping for absolute events

[Pekka Paalanen]

On Fri, 21 Sep 2012 15:04:17 +0100
Rob Bradford <rob at robster.org.uk> wrote:

> From: Rob Bradford <rob at linux.intel.com>
> 
> This quirk is designed for hardware that has the X and Y axes swapped for
> absolute events. Do this by rewriting the event such that the X and Y events
> are swapped.
> ---
>  src/evdev.c | 29 +++++++++++++++++++++++++----
>  1 file changed, 25 insertions(+), 4 deletions(-)
> 
> diff --git a/src/evdev.c b/src/evdev.c
> index 8848736..344974f 100644
> --- a/src/evdev.c
> +++ b/src/evdev.c
> @@ -129,6 +129,17 @@ evdev_process_absolute_motion(struct evdev_device *device,
>  	const int screen_width = device->output->current->width;
>  	const int screen_height = device->output->current->height;
>  
> +	if (device->quirks & EVDEV_QUIRK_SWAP_AXES) {
> +		switch (e->code) {
> +		case ABS_X:
> +			e->code = ABS_Y;
> +			break;
> +		case ABS_Y:
> +			e->code = ABS_X;
> +			break;
> +		}
> +	}
> +
>  	switch (e->code) {
>  	case ABS_X:
>  		device->abs.x =
> @@ -395,12 +406,22 @@ evdev_configure_device(struct evdev_device *device)
>  		if (TEST_BIT(abs_bits, ABS_MT_SLOT)) {
>  			ioctl(device->fd, EVIOCGABS(ABS_MT_POSITION_X),
>  			      &absinfo);
> -			device->abs.min_x = absinfo.minimum;
> -			device->abs.max_x = absinfo.maximum;
> +			if (device->quirks & EVDEV_QUIRK_SWAP_AXES) {
> +				device->abs.min_y = absinfo.minimum;
> +				device->abs.max_y = absinfo.maximum;
> +			} else {
> +				device->abs.min_x = absinfo.minimum;
> +				device->abs.max_x = absinfo.maximum;
> +			}
>  			ioctl(device->fd, EVIOCGABS(ABS_MT_POSITION_Y),
>  			      &absinfo);
> -			device->abs.min_y = absinfo.minimum;
> -			device->abs.max_y = absinfo.maximum;
> +			if (device->quirks & EVDEV_QUIRK_SWAP_AXES) {
> +				device->abs.min_x = absinfo.minimum;
> +				device->abs.max_x = absinfo.maximum;
> +			} else {
> +				device->abs.min_y = absinfo.minimum;
> +				device->abs.max_y = absinfo.maximum;
> +			}

As discussed in IRC, this looked like the wrong branch to swap this
stuff. This is MT limits, not plain ABS limits.

>  			device->is_mt = 1;
>  			device->mt.slot = 0;
>  			device->caps |= EVDEV_TOUCH;


Thanks,
pq