Re: [PATCH 0/3] platform/x86: int3472/discrete: Make it work with IPU6

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

On Thu, Nov 24, 2022 at 09:00:04PM +0100, Hans de Goede wrote:
> Hi All,
> 
> Here is a small set of patches to make the int3472/discrete code
> work with the sensor drivers bundled with the (unfortunately out of tree)
> IPU6 driver.
> 
> There are parts of the out of tree IPU6 code, like the sensor drivers,
> which can be moved to the mainline and I do plan to work on this at some
> point and then some of this might need to change. But for now the goal is
> to make the out of tree driver work with standard mainline distro kernels
> through e.g. dkms. Otherwise users need to run a patched kernel just for
> a couple of small differences.
> 
> This is basically a rewrite of this patch:
> https://github.com/intel/ipu6-drivers/blob/master/patch/int3472-support-independent-clock-and-LED-gpios-5.17%2B.patch
> 
> Wich users who want to use the IPU6 driver so far have had to manually
> apply to their kernels which is quite inconvenient.
> 
> This rewrite makes 2 significant changes:
> 
> 1. Don't break things on IPU3 platforms
> 
> 2. Instead of extending the int3472_sensor_configs[] quirks table for each
> model which needs "clken" and "pled" GPIOs, do this based on matching
> the ACPI HID of the ACPI device describing the sensor.

How can we be sure that a given sensor model will always be wired to the
same GPIOs on all platforms that integrate it with an IPU6 (or IPU3) ?

> The need for these GPIOs is a property of the specific sensor driver which
> binds using this same HID, so by using this we avoid having to extend the
> int3472_sensor_configs[] quirks table all the time.
> 
> This allows roling back the behavior to at least use a clk-framework
> clk instead of clken GPIO on a per sensor(-driver) basis as we mainline
> the sensor drivers, assuming that the drivers are switched over to the
> clk framework as part of their mainlining.
> 
> A bigger question is what to do with the privacy-led GPIO on IPU3
> we so far have turned the LED on/off at the same as te clock,
> but at least on some IPU6 models this won't work, because they only
> have a privacy-led GPIO and no clk_en GPIO (there is no sensor
> clk-control at all on some models).

Can we turn it on at the same time as the power then ?

> I think we should maybe move all models, including IPU3 based
> models over to using a normal GPIO for controlling the privacy-led
> to make things consistent.
> 
> And likewise (eventually) completely drop the "clken" GPIO this
> patch series introduces (with some sensors) and instead always model
> this through the clk-framework.
> 
> Regards,
> 
> Hans
> 
> 
> Hans de Goede (3):
>   platform/x86: int3472/discrete: Refactor GPIO to sensor mapping
>   platform/x86: int3472/discrete: Get the polarity from the _DSM entry
>   platform/x86: int3472/discrete: Add support for sensor-drivers which
>     expect clken + pled GPIOs
> 
>  drivers/platform/x86/intel/int3472/common.h   |  2 +-
>  drivers/platform/x86/intel/int3472/discrete.c | 92 ++++++++++++++++---
>  2 files changed, 78 insertions(+), 16 deletions(-)

-- 
Regards,

Laurent Pinchart