[PATCH synaptics] eventcomm: Drop requirement for a grab during init

[Hans de Goede]

Hi,

On 05/19/2014 03:45 AM, Peter Hutterer wrote:
> When we required a grab on the device, this was a shortcut so we didn't have
> to query the device only to realise we can't read events off it anyway. Now
> that we don't actually grab the device by default, this is unnecessary.
> 
> Something else may have a temporary grab on the device during init, in which
> case we just continue as usual and read events if and when they become
> available.
> 
> Somewhat related to #77480.
> 
> Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>

Looks good:

Reviewed-by: Hans de Goede <hdegoede at redhat.com>

Regards,

Hans

> ---
>  src/eventcomm.c | 37 ++++++++++---------------------------
>  1 file changed, 10 insertions(+), 27 deletions(-)
> 
> diff --git a/src/eventcomm.c b/src/eventcomm.c
> index 3f9da7c..6e45d56 100644
> --- a/src/eventcomm.c
> +++ b/src/eventcomm.c
> @@ -331,49 +331,33 @@ EventDeviceOffHook(InputInfoPtr pInfo)
>   * - BTN_TOOL_PEN is _not_ set
>   *
>   * @param evdev Libevdev handle
> - * @param test_grab If true, test whether an EVIOCGRAB is possible on the
> - * device. A failure to grab the event device returns in a failure.
>   *
>   * @return TRUE if the device is a touchpad or FALSE otherwise.
>   */
>  static Bool
> -event_query_is_touchpad(struct libevdev *evdev, BOOL test_grab)
> +event_query_is_touchpad(struct libevdev *evdev)
>  {
> -    int ret = FALSE, rc;
> -
> -    if (test_grab) {
> -        rc = libevdev_grab(evdev, LIBEVDEV_GRAB);
> -        if (rc < 0)
> -            return FALSE;
> -    }
> -
>      /* Check for ABS_X, ABS_Y, ABS_PRESSURE and BTN_TOOL_FINGER */
>      if (!libevdev_has_event_type(evdev, EV_SYN) ||
>          !libevdev_has_event_type(evdev, EV_ABS) ||
>          !libevdev_has_event_type(evdev, EV_KEY))
> -        goto unwind;
> +        return FALSE;
>  
>      if (!libevdev_has_event_code(evdev, EV_ABS, ABS_X) ||
>          !libevdev_has_event_code(evdev, EV_ABS, ABS_Y))
> -        goto unwind;
> +        return FALSE;
>  
>      /* we expect touchpad either report raw pressure or touches */
>      if (!libevdev_has_event_code(evdev, EV_KEY, BTN_TOUCH) &&
>          !libevdev_has_event_code(evdev, EV_ABS, ABS_PRESSURE))
> -        goto unwind;
> +        return FALSE;
>  
>      /* all Synaptics-like touchpad report BTN_TOOL_FINGER */
>      if (!libevdev_has_event_code(evdev, EV_KEY, BTN_TOOL_FINGER) ||
>          libevdev_has_event_code(evdev, EV_ABS, BTN_TOOL_PEN)) /* Don't match wacom tablets */
> -        goto unwind;
> +        return FALSE;
>  
> -    ret = TRUE;
> -
> - unwind:
> -    if (test_grab)
> -        libevdev_grab(evdev, LIBEVDEV_UNGRAB);
> -
> -    return (ret == TRUE);
> +    return TRUE;
>  }
>  
>  #define PRODUCT_ANY 0x0000
> @@ -565,8 +549,7 @@ EventQueryHardware(InputInfoPtr pInfo)
>      SynapticsPrivate *priv = (SynapticsPrivate *) pInfo->private;
>      struct eventcomm_proto_data *proto_data = priv->proto_data;
>  
> -    if (!event_query_is_touchpad(proto_data->evdev,
> -                                 (proto_data) ? proto_data->need_grab : TRUE))
> +    if (!event_query_is_touchpad(proto_data->evdev))
>          return FALSE;
>  
>      xf86IDrvMsg(pInfo, X_PROBED, "touchpad found\n");
> @@ -967,7 +950,7 @@ EventReadDevDimensions(InputInfoPtr pInfo)
>          proto_data->axis_map[i] = -1;
>      proto_data->cur_slot = -1;
>  
> -    if (event_query_is_touchpad(proto_data->evdev, proto_data->need_grab)) {
> +    if (event_query_is_touchpad(proto_data->evdev)) {
>          event_query_touch(pInfo);
>          event_query_axis_ranges(pInfo);
>      }
> @@ -1001,7 +984,7 @@ EventAutoDevProbe(InputInfoPtr pInfo, const char *device)
>  
>              rc = libevdev_new_from_fd(fd, &evdev);
>              if (rc >= 0) {
> -                touchpad_found = event_query_is_touchpad(evdev, TRUE);
> +                touchpad_found = event_query_is_touchpad(evdev);
>                  libevdev_free(evdev);
>              }
>  
> @@ -1043,7 +1026,7 @@ EventAutoDevProbe(InputInfoPtr pInfo, const char *device)
>  
>              rc = libevdev_new_from_fd(fd, &evdev);
>              if (rc >= 0) {
> -                touchpad_found = event_query_is_touchpad(evdev, TRUE);
> +                touchpad_found = event_query_is_touchpad(evdev);
>                  libevdev_free(evdev);
>                  if (touchpad_found) {
>                      xf86IDrvMsg(pInfo, X_PROBED, "auto-dev sets device to %s\n",
>