Re: [PATCH] HID: input: Add support for Programmable Buttons

[Hans de Goede]

Hi,

On 5/19/21 6:03 PM, Thomas Weißschuh wrote:
> From: Thomas Weißschuh <thomas@xxxxxxxx>
> 
> Map them to KEY_MACRO# event codes.
> 
> These buttons are defined by HID as follows:
> "The user defines the function of these buttons to control software
> applications or GUI objects."
> 
> This matches the semantics of the KEY_MACRO# input event codes that
> Linux supports.
> 
> Signed-off-by: Thomas Weißschuh <thomas@xxxxxxxx>
> ---
>  drivers/hid/hid-debug.c | 11 +++++++++++
>  drivers/hid/hid-input.c |  1 +
>  2 files changed, 12 insertions(+)
> 
> diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
> index 59f8d716d78f..0e76d9b4530a 100644
> --- a/drivers/hid/hid-debug.c
> +++ b/drivers/hid/hid-debug.c
> @@ -122,6 +122,7 @@ static const struct hid_usage_entry hid_usage_table[] = {
>    {  9, 0, "Button" },
>    { 10, 0, "Ordinal" },
>    { 12, 0, "Consumer" },
> +      {0, 0x003, "ProgrammableButtons"},
>        {0, 0x238, "HorizontalWheel"},
>    { 13, 0, "Digitizers" },
>      {0, 0x01, "Digitizer"},
> @@ -939,6 +940,16 @@ static const char *keys[KEY_MAX + 1] = {
>  	[KEY_KBDINPUTASSIST_NEXTGROUP] = "KbdInputAssistNextGroup",
>  	[KEY_KBDINPUTASSIST_ACCEPT] = "KbdInputAssistAccept",
>  	[KEY_KBDINPUTASSIST_CANCEL] = "KbdInputAssistCancel",
> +	[KEY_MACRO1] = "Macro1", [KEY_MACRO2] = "Macro2", [KEY_MACRO3] = "Macro3",
> +	[KEY_MACRO4] = "Macro4", [KEY_MACRO5] = "Macro5", [KEY_MACRO6] = "Macro6",
> +	[KEY_MACRO7] = "Macro7", [KEY_MACRO8] = "Macro8", [KEY_MACRO9] = "Macro9",
> +	[KEY_MACRO10] = "Macro10", [KEY_MACRO11] = "Macro11", [KEY_MACRO12] = "Macro12",
> +	[KEY_MACRO13] = "Macro13", [KEY_MACRO14] = "Macro14", [KEY_MACRO15] = "Macro15",
> +	[KEY_MACRO16] = "Macro16", [KEY_MACRO17] = "Macro17", [KEY_MACRO18] = "Macro18",
> +	[KEY_MACRO19] = "Macro19", [KEY_MACRO20] = "Macro20", [KEY_MACRO21] = "Macro21",
> +	[KEY_MACRO22] = "Macro22", [KEY_MACRO23] = "Macro23", [KEY_MACRO24] = "Macro24",
> +	[KEY_MACRO25] = "Macro25", [KEY_MACRO26] = "Macro26", [KEY_MACRO27] = "Macro27",
> +	[KEY_MACRO28] = "Macro28", [KEY_MACRO29] = "Macro29", [KEY_MACRO30] = "Macro30",
>  };
>  
>  static const char *relatives[REL_MAX + 1] = {
> diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
> index 18f5e28d475c..7d4dee58d869 100644
> --- a/drivers/hid/hid-input.c
> +++ b/drivers/hid/hid-input.c
> @@ -632,6 +632,7 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
>  				else
>  					code += BTN_TRIGGER_HAPPY - 0x10;
>  				break;
> +		case HID_CP_CONSUMER_CONTROL: code += KEY_MACRO1; break;

Shouldn't there be a check here to ensure that we don't map things above KEY_MACRO30 ?
if we do that then we start hitting other codes like KEY_MACRO_RECORD_START and eventually
BTN_TRIGGER_HAPPY and after the BTN_TRIGGER_HAPPY range we go over KEY_MAX which I think
is not supported ?

Regards,

Hans



>  		default:
>  			switch (field->physical) {
>  			case HID_GD_MOUSE:
> 
> base-commit: efd8929b9eec1cde120abb36d76dd00ff6711023
>