Re: [PATCH v9 2/3] x86: add support for Huawei WMI hotkeys.

[Randy Dunlap]

On 12/3/18 10:53 AM, Ayman Bagabas wrote:
> This driver adds support for missing hotkeys on some Huawei laptops.
> Laptops such as the Matebook X have non functioning hotkeys. Whereas
> newer laptops such as the Matebook X Pro come with working hotkeys out
> of the box.
> 
> Old laptops, such as the Matebook X, report hotkey events through ACPI
> device "\WMI0". However, new laptops, such as the Matebook X Pro,
> does not have this WMI device.
> 
> All the hotkeys on the Matebook X Pro work fine
> without this patch except (micmute, wlan, and huawei key). These keys
> and the brightness keys report events to "\AMW0" ACPI device. One
> problem is that brightness keys on the Matebook X Pro work without this
> patch. This results in reporting two brightness key press
> events one is captured by ACPI and another by this driver.
> 
> A solution would be to check if such event came from the "\AMW0" WMI driver
> then skip reporting event. Another solution would be to leave this to
> user-space to handle. Which can be achieved by using "hwdb" tables and
> remap those keys to "unknown". This solution seems more natural to me
> because it leaves the decision to user-space.
> 
> Signed-off-by: Ayman Bagabas <ayman.bagabas@xxxxxxxxx>
> ---
>  drivers/platform/x86/Kconfig      |  16 +++
>  drivers/platform/x86/Makefile     |   1 +
>  drivers/platform/x86/huawei-wmi.c | 226 ++++++++++++++++++++++++++++++
>  3 files changed, 243 insertions(+)
>  create mode 100644 drivers/platform/x86/huawei-wmi.c
> 
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 87f70e8f4dd0..27db3ce7a1e1 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -1292,6 +1292,22 @@ config INTEL_ATOMISP2_PM
>  	  To compile this driver as a module, choose M here: the module
>  	  will be called intel_atomisp2_pm.
>  
> +config HUAWEI_WMI
> +	tristate "Huawei WMI hotkeys driver"
> +	depends on ACPI_WMI
> +	depends on INPUT
> +	select INPUT_SPARSEKMAP
> +	select LEDS_CLASS

but LEDS_CLASS is only available if NEW_LEDS is set/enabled, so it either
depends on LEDS_CLASS... or it needs to select NEW_LEDS, which is what other
drivers in this Kconfig file do, even though our b.d. has said a few times
that any one driver should not "select" => enable an entire subsystem,
so they all should be "depends on NEW_LEDS" IMHO.

> +	select LEDS_TRIGGERS
> +	select LEDS_TRIGGER_AUDIO
> +	help
> +	  This driver provides support for Huawei WMI hotkeys.
> +	  It enables the missing keys and adds support to the micmute
> +	  LED found on some of these laptops.
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called huawei-wmi.
> +
>  endif # X86_PLATFORM_DEVICES
>  
>  config PMC_ATOM


-- 
~Randy