Moving drivers/leds/dell-led.c to drivers/platform/x86

Moving drivers/leds/dell-led.c to drivers/platform/x86

[Michał Kępień]

Hi everyone,

Back in January [1], while working on the dell-smbios module, I
suggested that the code present in drivers/leds/dell-led.c could be
moved to drivers/platform/x86 for coherency.  I decided to revisit that
idea.

dell-led consists of two major parts:

  - the part handling an "Activity LED" present in Dell Latitude 2100
    netbooks, introduced in 72dcd8d; it registers a LED device and uses
    a special WMI interface to control its state,

  - the part exposing a "microphone mute LED interface", introduced in
    db6d8cc; this interface is used by sound/pci/hda/dell_wmi_helper.c;
    while the original implementation also used a WMI interface, it was
    changed to use dell-smbios in cf0d7ea and 0c41a08.

I believe both parts could (and should) be moved to drivers/platform/x86
as drivers/platform/x86/dell-laptop.c already handles a bunch of LEDs
and drivers/leds/dell-led.c is the only dell-smbios user outside of
drivers/platform/x86.

My question to you, the maintainers of the relevant drivers and
subsystems, is whether you would like to see such a move happen.  I have
prepared a draft patch series which:

  - moves the "microphone mute LED interface" to dell-laptop.c,
    effectively causing sound/pci/hda/dell_wmi_helper.c to depend on
    CONFIG_DELL_LAPTOP instead of CONFIG_LEDS_DELL_NETBOOKS,

  - moves the "Activity LED" part to a new file, tentatively called
    drivers/platform/x86/dell-wmi-led.c.

Merging the "Activity LED" part with drivers/platform/x86/dell-wmi.c is
not really clean because dell-wmi handles a different GUID, which AFAIK
is not related in any way to the GUID used by dell-led.

So, before I spam *three* subsystem mailing lists with a bunch of
patches, I would love to hear from the maintainers of both drivers/leds
and drivers/platform/x86 whether there are any arguments against such a
move.  Meanwhile, I will keep polishing the patch series and if there is
no strong disagreement from any party involved, I will post the series
next week or so, so that we can discuss code and not just ideas.

As a side note, if anyone reading this has access to a Dell device which
has an "Activity LED" and/or a "microphone mute LED" currently supported
by dell-led, I would love to hear from you as I do not have the hardware
needed to practically test the patch series I am working on.

Looking forward to hearing from you,

[1] https://www.spinics.net/lists/platform-driver-x86/msg08143.html

-- 
Best regards,
Michał Kępień

Re: Moving drivers/leds/dell-led.c to drivers/platform/x86

[Pali Rohár]

On Monday 13 June 2016 15:49:42 Michał Kępień wrote:
> Hi everyone,
> 
> Back in January [1], while working on the dell-smbios module, I
> suggested that the code present in drivers/leds/dell-led.c could be
> moved to drivers/platform/x86 for coherency.  I decided to revisit that
> idea.
> 
> dell-led consists of two major parts:
> 
>   - the part handling an "Activity LED" present in Dell Latitude 2100
>     netbooks, introduced in 72dcd8d; it registers a LED device and uses
>     a special WMI interface to control its state,
> 
>   - the part exposing a "microphone mute LED interface", introduced in
>     db6d8cc; this interface is used by sound/pci/hda/dell_wmi_helper.c;
>     while the original implementation also used a WMI interface, it was
>     changed to use dell-smbios in cf0d7ea and 0c41a08.
> 
> I believe both parts could (and should) be moved to drivers/platform/x86
> as drivers/platform/x86/dell-laptop.c already handles a bunch of LEDs
> and drivers/leds/dell-led.c is the only dell-smbios user outside of
> drivers/platform/x86.
> 
> My question to you, the maintainers of the relevant drivers and
> subsystems, is whether you would like to see such a move happen.  I have
> prepared a draft patch series which:
> 
>   - moves the "microphone mute LED interface" to dell-laptop.c,
>     effectively causing sound/pci/hda/dell_wmi_helper.c to depend on
>     CONFIG_DELL_LAPTOP instead of CONFIG_LEDS_DELL_NETBOOKS,
> 
>   - moves the "Activity LED" part to a new file, tentatively called
>     drivers/platform/x86/dell-wmi-led.c.
> 
> Merging the "Activity LED" part with drivers/platform/x86/dell-wmi.c is
> not really clean because dell-wmi handles a different GUID, which AFAIK
> is not related in any way to the GUID used by dell-led.
> 
> So, before I spam *three* subsystem mailing lists with a bunch of
> patches, I would love to hear from the maintainers of both drivers/leds
> and drivers/platform/x86 whether there are any arguments against such a
> move.  Meanwhile, I will keep polishing the patch series and if there is
> no strong disagreement from any party involved, I will post the series
> next week or so, so that we can discuss code and not just ideas.
> 
> As a side note, if anyone reading this has access to a Dell device which
> has an "Activity LED" and/or a "microphone mute LED" currently supported
> by dell-led, I would love to hear from you as I do not have the hardware
> needed to practically test the patch series I am working on.
> 
> Looking forward to hearing from you,
> 
> [1] https://www.spinics.net/lists/platform-driver-x86/msg08143.html

I was talking with Michał and I supports this move.

-- 
Pali Rohár
pali.rohar@gmail.com

Re: Moving drivers/leds/dell-led.c to drivers/platform/x86

[Jacek Anaszewski]

Hi Michał,

I have no objections.

Best regards,
Jacek Anaszewski

On 06/13/2016 03:49 PM, Michał Kępień wrote:
> Hi everyone,
>
> Back in January [1], while working on the dell-smbios module, I
> suggested that the code present in drivers/leds/dell-led.c could be
> moved to drivers/platform/x86 for coherency.  I decided to revisit that
> idea.
>
> dell-led consists of two major parts:
>
>    - the part handling an "Activity LED" present in Dell Latitude 2100
>      netbooks, introduced in 72dcd8d; it registers a LED device and uses
>      a special WMI interface to control its state,
>
>    - the part exposing a "microphone mute LED interface", introduced in
>      db6d8cc; this interface is used by sound/pci/hda/dell_wmi_helper.c;
>      while the original implementation also used a WMI interface, it was
>      changed to use dell-smbios in cf0d7ea and 0c41a08.
>
> I believe both parts could (and should) be moved to drivers/platform/x86
> as drivers/platform/x86/dell-laptop.c already handles a bunch of LEDs
> and drivers/leds/dell-led.c is the only dell-smbios user outside of
> drivers/platform/x86.
>
> My question to you, the maintainers of the relevant drivers and
> subsystems, is whether you would like to see such a move happen.  I have
> prepared a draft patch series which:
>
>    - moves the "microphone mute LED interface" to dell-laptop.c,
>      effectively causing sound/pci/hda/dell_wmi_helper.c to depend on
>      CONFIG_DELL_LAPTOP instead of CONFIG_LEDS_DELL_NETBOOKS,
>
>    - moves the "Activity LED" part to a new file, tentatively called
>      drivers/platform/x86/dell-wmi-led.c.
>
> Merging the "Activity LED" part with drivers/platform/x86/dell-wmi.c is
> not really clean because dell-wmi handles a different GUID, which AFAIK
> is not related in any way to the GUID used by dell-led.
>
> So, before I spam *three* subsystem mailing lists with a bunch of
> patches, I would love to hear from the maintainers of both drivers/leds
> and drivers/platform/x86 whether there are any arguments against such a
> move.  Meanwhile, I will keep polishing the patch series and if there is
> no strong disagreement from any party involved, I will post the series
> next week or so, so that we can discuss code and not just ideas.
>
> As a side note, if anyone reading this has access to a Dell device which
> has an "Activity LED" and/or a "microphone mute LED" currently supported
> by dell-led, I would love to hear from you as I do not have the hardware
> needed to practically test the patch series I am working on.
>
> Looking forward to hearing from you,
>
> [1] https://www.spinics.net/lists/platform-driver-x86/msg08143.html
>