Re: [PATCH] input: alps-fix the issue alps cs19 trackstick do not work.

From: Pali RohÃr
Date: Mon May 27 2019 - 06:12:33 EST


Hi!

On Monday 27 May 2019 05:44:22 XiaoXiao Liu wrote:
> The alps devices which detected to use the ALPS_PROTO_V8 procotol contains
> ALPS touchpad and ALPS trackstick.The ALPS_PROTO_V8 procotol do not
> support the trackstick device process by default.

Normally PS/2 device handled by alps.c is touchpad and in some cases
touchpad sends also trackstick data in that one PS/2 channel.

Does it mean that your device (reported to kernel) sends only trackstick
packets and not touchpad?

> When the trackstick was detected to use ALPS_PROTO_V8 procotol,
> the v8 process_packet method alps_process_packet_ss4_v2 will reject to
> report the data when the device using ALPS_PROTO_V8 procotol is not set
> the ALPS_DUALPOINT flag.
>
> The alps cs19 trackstick is detected to use the ALPS_PROTO_V8 procotol
> but without ALPS_DUALPOINT flag, the alps driver will not report the
> input data. so the trackstick will not work.
>
> solution: when the alps cs19 device detected, set the device
> ALPS_DUALPOINT flag,then the input data will be processed.
>
> Signed-off-by: XiaoXiao Liu <sliuuxiaonxiao@xxxxxxxxx>
> ---
> drivers/input/mouse/alps.c | 25 +++++++++++++++++++++++--
> 1 file changed, 23 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
> index 0a6f7ca883e7..a54677cf7474 100644
> --- a/drivers/input/mouse/alps.c
> +++ b/drivers/input/mouse/alps.c
> @@ -24,7 +24,7 @@
>
> #include "psmouse.h"
> #include "alps.h"
> -
> +#include "trackpoint.h"
> /*
> * Definitions for ALPS version 3 and 4 command mode protocol
> */
> @@ -220,6 +220,23 @@ static bool alps_is_valid_first_byte(struct alps_data *priv,
> return (data & priv->mask0) == priv->byte0;
> }
>
> +static int alps_check_cs19_trackstick(struct psmouse *psmouse)
> +{
> + u8 param[2] = { 0 };
> + int error;
> +
> + error = ps2_command(&psmouse->ps2dev,
> + param, MAKE_PS2_CMD(0, 2, TP_READ_ID));
> + if (error)
> + return error;
> +
> + if (param[0] == TP_VARIANT_ALPS && param[1] & 0x20) {

I guess that you want parenthesis around (param[1] & 0x20). And also
describe what that 0x20 constant means.

> + psmouse_warn(psmouse, "It is alps cs19 trackstick");

It is not a warning.

> + return 0;
> + }
> + return -1;
> +}
> +
> static void alps_report_buttons(struct input_dev *dev1, struct input_dev *dev2,
> int left, int right, int middle)
> {
> @@ -2568,8 +2585,12 @@ static int alps_update_dual_info_ss4_v2(unsigned char otp[][4],
> alps_exit_command_mode(psmouse);
> ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE);
>
> - if (reg_val == 0x0C || reg_val == 0x1D)
> + if (reg_val == 0x0C || reg_val == 0x1D) {

Hm... why your device does not match these constants?

> + is_dual = true;
> + } else if (alps_check_cs19_trackstick(psmouse) == 0) {
> + //For support Thinkpad CS19 TrackStick
> is_dual = true;
> + }
> }
> }
>

--
Pali RohÃr
pali.rohar@xxxxxxxxx