Re: [PATCH v3 0/6] Introduce intel_skl_int3472 module

[Daniel Scally <djrscally@gmail.com>]

Hi Hans

On 04/03/2021 13:37, Hans de Goede wrote:
> Hi,
>
> On 2/22/21 2:07 PM, Daniel Scally wrote:
>> v1 for this series was originally 14-18 of this series:
>> https://lore.kernel.org/linux-media/20201130133129.1024662-1-djrscally@gmail.com/T/#m91934e12e3d033da2e768e952ea3b4a125ee3e67
>>
>> v2 was here:
>> https://lore.kernel.org/platform-driver-x86/20210118003428.568892-1-djrscally@gmail.com/
>>
>> Series level changelog:
>>
>> 	- Dropped the patch moving acpi_lpss_dep() to utils since it's not used
>> 	in acpi_dev_get_dependent_dev() anymore.
>> 	- Replaced it with a patch extending acpi_walk_dep_device_list() to be
>> 	able to apply a given callback against each device in acpi_dep_list
>> 	- Dropped the patch creating acpi_i2c_dev_name() and simply open coded
>> 	that functionality.
>>
>> This has been tested on a number of devices, but currently **not** on a device
>> designed for ChromeOS, which we ideally need to do to ensure no regression
>> caused by replacing the tps68470 MFD driver. Sakari / Tomasz, is there any way
>> you could help with that? Unfortunately, I don't have a device to test it on
>> myself.
>>
>> Original cover letter: 
>>
>> At the moment in the kernel the ACPI _HID INT3472 is taken by the tps68470
>> MFD driver, but that driver can only handle some of the cases of that _HID
>> that we see. There are at least these three possibilities:
>>
>> 1. INT3472 devices that provide GPIOs through the usual framework and run
>>    power and clocks through an operation region; this is the situation that
>>    the current module handles and is seen on ChromeOS devices
>> 2. INT3472 devices that provide GPIOs, plus clocks and regulators that are
>>    meant to be driven through the usual frameworks, usually seen on devices
>>    designed to run Windows
>> 3. INT3472 devices that don't actually represent a physical tps68470, but
>>    are being used as a convenient way of grouping a bunch of system GPIO
>>    lines that are intended to enable power and clocks for sensors which
>>    are called out as dependent on them. Also seen on devices designed to
>>    run Windows.
>>
>> This series introduces a new module which registers:
>>
>> 1. An i2c driver that determines which scenario (#1 or #2) applies to the
>>    machine and registers platform devices to be bound to GPIO, OpRegion,
>>    clock and regulator drivers as appropriate.
>> 2. A platform driver that binds to the dummy INT3472 devices described in
>>    #3
>>
>> The platform driver for the dummy device registers the GPIO lines that
>> enable the clocks and regulators to the sensors via those frameworks so
>> that sensor drivers can consume them in the usual fashion. The existing
>> GPIO and OpRegion tps68470 drivers will work with the i2c driver that's
>> registered. Clock and regulator drivers are available but have not so far been
>> tested, so aren't part of this series.
>>
>> The existing mfd/tps68470.c driver being thus superseded, it is removed.
> Thank you for this patch series. Since there have already been a whole
> bunch of review-comments, I've not taken a detailed look at this yet.


No problem, I'm hoping to do a v3 over the weekend anyway.


> I do wonder if you have thought about how this series should be merged?
> This series is spread over quite a few subsytems and since there are
> various interdependencies in the patches it is probably best if it gets
> merged in its entirety through a single tree.
>
> I guess that merging though either Rafael's (drivers/acpi) tree or
> Lee's (drivers/mfd) tree makes the most sense.
>
> As drivers/platform/x86 maintainer I'm happy with whatever solution
> works for the other subsystem maintainers.


I also think it's a good idea to go through a single tree, and my plan
was to raise that probably after the next review round or so, but I
hadn't gotten as far as thinking about whos tree it should be or
anything yet. To be honest I'm not sure what factors dictate which
choice is best in that regard; handling complex git merges is a bit
outside my experience.

>
> Regards,
>
> Hans
>
>
>
>
>> Thanks
>> Dan
>>
>> Daniel Scally (6):
>>   ACPI: scan: Extend acpi_walk_dep_device_list()
>>   ACPI: scan: Add function to fetch dependent of acpi device
>>   i2c: core: Add a format macro for I2C device names
>>   gpiolib: acpi: Export acpi_get_gpiod()
>>   platform/x86: Add intel_skl_int3472 driver
>>   mfd: tps68470: Remove tps68470 MFD driver
>>
>>  MAINTAINERS                                   |   5 +
>>  drivers/acpi/ec.c                             |   2 +-
>>  drivers/acpi/pmic/Kconfig                     |   2 +-
>>  drivers/acpi/pmic/intel_pmic_chtdc_ti.c       |   2 +-
>>  drivers/acpi/scan.c                           |  92 ++-
>>  drivers/gpio/Kconfig                          |   2 +-
>>  drivers/gpio/gpiolib-acpi.c                   |  38 +-
>>  drivers/i2c/i2c-core-acpi.c                   |   2 +-
>>  drivers/i2c/i2c-core-base.c                   |   4 +-
>>  drivers/mfd/Kconfig                           |  18 -
>>  drivers/mfd/Makefile                          |   1 -
>>  drivers/mfd/tps68470.c                        |  97 ---
>>  drivers/platform/surface/surface3_power.c     |   2 +-
>>  drivers/platform/x86/Kconfig                  |   2 +
>>  drivers/platform/x86/Makefile                 |   1 +
>>  drivers/platform/x86/intel-int3472/Kconfig    |  31 +
>>  drivers/platform/x86/intel-int3472/Makefile   |   4 +
>>  .../intel-int3472/intel_skl_int3472_common.c  | 106 ++++
>>  .../intel-int3472/intel_skl_int3472_common.h  | 110 ++++
>>  .../intel_skl_int3472_discrete.c              | 592 ++++++++++++++++++
>>  .../intel_skl_int3472_tps68470.c              | 113 ++++
>>  include/acpi/acpi_bus.h                       |   8 +
>>  include/linux/acpi.h                          |   4 +-
>>  include/linux/gpio/consumer.h                 |   7 +
>>  include/linux/i2c.h                           |   3 +
>>  25 files changed, 1100 insertions(+), 148 deletions(-)
>>  delete mode 100644 drivers/mfd/tps68470.c
>>  create mode 100644 drivers/platform/x86/intel-int3472/Kconfig
>>  create mode 100644 drivers/platform/x86/intel-int3472/Makefile
>>  create mode 100644 drivers/platform/x86/intel-int3472/intel_skl_int3472_common.c
>>  create mode 100644 drivers/platform/x86/intel-int3472/intel_skl_int3472_common.h
>>  create mode 100644 drivers/platform/x86/intel-int3472/intel_skl_int3472_discrete.c
>>  create mode 100644 drivers/platform/x86/intel-int3472/intel_skl_int3472_tps68470.c
>>