On Tue, Dec 08, 2020 at 11:01:50PM +0200, Vasyl Vavrychuk wrote:
> From: Mathias Crombez <mathias.crombez@xxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
I don't believe this is appropriate for stable, looks like
a new feature to me.
>
> Without multi-touch slots allocated, ABS_MT_SLOT events will be lost by
> input_handle_abs_event.
>
> Signed-off-by: Mathias Crombez <mathias.crombez@xxxxxxxxxxxx>
> Signed-off-by: Vasyl Vavrychuk <vasyl.vavrychuk@xxxxxxxxxxxxxxx>
> Tested-by: Vasyl Vavrychuk <vasyl.vavrychuk@xxxxxxxxxxxxxxx>
> ---
> v2: fix patch corrupted by corporate email server
>
> drivers/virtio/Kconfig | 11 +++++++++++
> drivers/virtio/virtio_input.c | 8 ++++++++
> 2 files changed, 19 insertions(+)
>
> diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
> index 7b41130d3f35..2cfd5b01d96d 100644
> --- a/drivers/virtio/Kconfig
> +++ b/drivers/virtio/Kconfig
> @@ -111,6 +111,17 @@ config VIRTIO_INPUT
>
> If unsure, say M.
>
> +config VIRTIO_INPUT_MULTITOUCH_SLOTS
> + depends on VIRTIO_INPUT
> + int "Number of multitouch slots"
> + range 0 64
> + default 10
> + help
> + Define the number of multitouch slots used. Default to 10.
> + This parameter is unused if there is no multitouch capability.
> +
> + 0 will disable the feature.
> +
Most people won't be using this config so the defaults matter. So why 10? 10 fingers?
And where does 64 come from?
> config VIRTIO_MMIO
> tristate "Platform bus driver for memory mapped virtio devices"
> depends on HAS_IOMEM && HAS_DMA
> diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c
> index f1f6208edcf5..13f3d90e6c30 100644
> --- a/drivers/virtio/virtio_input.c
> +++ b/drivers/virtio/virtio_input.c
> @@ -7,6 +7,7 @@
>
> #include <uapi/linux/virtio_ids.h>
> #include <uapi/linux/virtio_input.h>
> +#include <linux/input/mt.h>
>
> struct virtio_input {
> struct virtio_device *vdev;
> @@ -205,6 +206,7 @@ static int virtinput_probe(struct virtio_device *vdev)
> unsigned long flags;
> size_t size;
> int abs, err;
> + bool is_mt = false;
>
> if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
> return -ENODEV;
> @@ -287,9 +289,15 @@ static int virtinput_probe(struct virtio_device *vdev)
> for (abs = 0; abs < ABS_CNT; abs++) {
> if (!test_bit(abs, vi->idev->absbit))
> continue;
> + if (input_is_mt_value(abs))
> + is_mt = true;
> virtinput_cfg_abs(vi, abs);
> }
> }
> + if (is_mt)
> + input_mt_init_slots(vi->idev,
> + CONFIG_VIRTIO_INPUT_MULTITOUCH_SLOTS,
> + INPUT_MT_DIRECT);
Do we need the number in config space maybe? And maybe with a feature
bit so host can find out whether guest supports MT?
>
> virtio_device_ready(vdev);
> vi->ready = true;
> --
> 2.23.0
