2019-03-19 22:49:23

by Peter Hutterer

Subject: [PATCH] HID: logitech: Handle 0 scroll events for the m560

hidpp_scroll_counter_handle_scroll() doesn't expect a 0-value scroll event, it
gets interpreted as a negative scroll direction event. This can cause scroll
direction resets and thus broken scrolling.

Reported-and-tested-by: Aimo Mets?l? <[email protected]>
Signed-off-by: Peter Hutterer <[email protected]>
---
drivers/hid/hid-logitech-hidpp.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index 15ed6177a7a3..f040c8a7f9a9 100644
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -2608,8 +2608,9 @@ static int m560_raw_event(struct hid_device *hdev, u8 *data, int size)
input_report_rel(mydata->input, REL_Y, v);

v = hid_snto32(data[6], 8);
- hidpp_scroll_counter_handle_scroll(
- &hidpp->vertical_wheel_counter, v);
+ if (v != 0)
+ hidpp_scroll_counter_handle_scroll(
+ &hidpp->vertical_wheel_counter, v);

input_sync(mydata->input);
}
--
2.20.1

2019-03-20 14:31:06

by Benjamin Tissoires

Subject: Re: [PATCH] HID: logitech: Handle 0 scroll events for the m560

On Tue, Mar 19, 2019 at 11:48 PM Peter Hutterer
<[email protected]> wrote:
>
> hidpp_scroll_counter_handle_scroll() doesn't expect a 0-value scroll event, it
> gets interpreted as a negative scroll direction event. This can cause scroll
> direction resets and thus broken scrolling.
>
> Reported-and-tested-by: Aimo Metsälä <[email protected]>
> Signed-off-by: Peter Hutterer <[email protected]>
> ---

Added the 'Fixes' and "cc: stable" tags and patch applied to
for-5.1/upstream-fixes

Cheers,
Benjamin

> drivers/hid/hid-logitech-hidpp.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
> index 15ed6177a7a3..f040c8a7f9a9 100644
> --- a/drivers/hid/hid-logitech-hidpp.c
> +++ b/drivers/hid/hid-logitech-hidpp.c
> @@ -2608,8 +2608,9 @@ static int m560_raw_event(struct hid_device *hdev, u8 *data, int size)
> input_report_rel(mydata->input, REL_Y, v);
>
> v = hid_snto32(data[6], 8);
> - hidpp_scroll_counter_handle_scroll(
> - &hidpp->vertical_wheel_counter, v);
> + if (v != 0)
> + hidpp_scroll_counter_handle_scroll(
> + &hidpp->vertical_wheel_counter, v);
>
> input_sync(mydata->input);
> }
> --
> 2.20.1
>