Re: [PATCH v6 1/4] HID: wacom: Advertise SW_MUTE_DEVICE capability prior to registration

From: Lee Jones

Date: Mon Jul 20 2026 - 09:00:08 EST


Is Jason back in this week?

Note that all of the Sashiko review comments are pre-existing issues.

> Input subsystem guidelines require that device capabilities are advertised
> before the input device is registered. The Wacom driver was violating
> this by advertising the SW_MUTE_DEVICE capability post-registration in
> wacom_set_shared_values() (and duplicating it in device-specific setup
> cases).
>
> Resolve this by moving the SW_MUTE_DEVICE capability setup to
> wacom_setup_touch_input_capabilities() for all touch devices that support
> it, excluding TabletPC devices.
>
> Additionally, replace the lookup-dependent
> 'wacom_wac->shared->touch->product' references with 'hdev->product'
> inside wacom_setup_touch_input_capabilities() as 'hdev' is already
> available and represents the touch device itself.
>
> Fixes: d2ec58aee8b1 ("HID: wacom: generic: support generic touch switch")
> Signed-off-by: Lee Jones <lee@xxxxxxxxxx>
> ---
>
> v4 -> v5: New patch used to split out SW_MUTE_DEVICE as per Jason's request
> v5 -> v6: Unconditionally advertise SW_MUTE_DEVICE on generic touch devices
>
> drivers/hid/wacom_sys.c | 6 ------
> drivers/hid/wacom_wac.c | 19 +++++++++++--------
> 2 files changed, 11 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
> index 0eafa483b7f7..6c2a3ddfe366 100644
> --- a/drivers/hid/wacom_sys.c
> +++ b/drivers/hid/wacom_sys.c
> @@ -2359,12 +2359,6 @@ static void wacom_set_shared_values(struct wacom_wac *wacom_wac)
> wacom_wac->shared->is_touch_on = true;
> }
>
> - if (wacom_wac->shared->has_mute_touch_switch &&
> - wacom_wac->shared->touch_input) {
> - set_bit(EV_SW, wacom_wac->shared->touch_input->evbit);
> - input_set_capability(wacom_wac->shared->touch_input, EV_SW,
> - SW_MUTE_DEVICE);
> - }
> }
>
> static int wacom_parse_and_register(struct wacom *wacom, bool wireless)
> diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
> index a29bf051ada7..32c4fd03479e 100644
> --- a/drivers/hid/wacom_wac.c
> +++ b/drivers/hid/wacom_wac.c
> @@ -3953,6 +3953,8 @@ int wacom_setup_pen_input_capabilities(struct input_dev *input_dev,
> int wacom_setup_touch_input_capabilities(struct input_dev *input_dev,
> struct wacom_wac *wacom_wac)
> {
> + struct wacom *wacom = container_of(wacom_wac, struct wacom, wacom_wac);
> + struct hid_device *hdev = wacom->hdev;
> struct wacom_features *features = &wacom_wac->features;
>
> if (!(features->device_type & WACOM_DEVICETYPE_TOUCH))
> @@ -3963,9 +3965,12 @@ int wacom_setup_touch_input_capabilities(struct input_dev *input_dev,
> else
> __set_bit(INPUT_PROP_POINTER, input_dev->propbit);
>
> - if (features->type == HID_GENERIC)
> + if (features->type == HID_GENERIC) {
> + input_dev->evbit[0] |= BIT_MASK(EV_SW);
> + __set_bit(SW_MUTE_DEVICE, input_dev->swbit);
> /* setup has already been done */
> return 0;
> + }
>
> input_dev->evbit[0] |= BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
> __set_bit(BTN_TOUCH, input_dev->keybit);
> @@ -3997,19 +4002,17 @@ int wacom_setup_touch_input_capabilities(struct input_dev *input_dev,
> input_dev->evbit[0] |= BIT_MASK(EV_SW);
> __set_bit(SW_MUTE_DEVICE, input_dev->swbit);
>
> - if (wacom_wac->shared->touch->product == 0x361) {
> + if (hdev->product == 0x361) {
> input_set_abs_params(input_dev, ABS_MT_POSITION_X,
> 0, 12440, 4, 0);
> input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
> 0, 8640, 4, 0);
> - }
> - else if (wacom_wac->shared->touch->product == 0x360) {
> + } else if (hdev->product == 0x360) {
> input_set_abs_params(input_dev, ABS_MT_POSITION_X,
> 0, 8960, 4, 0);
> input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
> 0, 5920, 4, 0);
> - }
> - else if (wacom_wac->shared->touch->product == 0x393) {
> + } else if (hdev->product == 0x393) {
> input_set_abs_params(input_dev, ABS_MT_POSITION_X,
> 0, 6400, 4, 0);
> input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
> @@ -4039,8 +4042,8 @@ int wacom_setup_touch_input_capabilities(struct input_dev *input_dev,
> fallthrough;
>
> case WACOM_27QHDT:
> - if (wacom_wac->shared->touch->product == 0x32C ||
> - wacom_wac->shared->touch->product == 0xF6) {
> + if (hdev->product == 0x32C ||
> + hdev->product == 0xF6) {
> input_dev->evbit[0] |= BIT_MASK(EV_SW);
> __set_bit(SW_MUTE_DEVICE, input_dev->swbit);
> wacom_wac->has_mute_touch_switch = true;
> --
> 2.55.0.141.g00534a21ce-goog
>

--
Lee Jones