linux-kernel - Re: [PATCH] mfd: intel_soc_pmic_crc: Use PWM_LOOKUP_WITH

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CAHp75VcYk_7Wb2bas2Z0db3gsCQL5Qp2sKzj=sJjp_WdHxoRpg@mail.gmail.com>
Date: Sat, 25 May 2024 17:52:23 +0300
From: Andy Shevchenko <andy.shevchenko@...il.com>
To: Hans de Goede <hdegoede@...hat.com>
Cc: Andy Shevchenko <andy@...nel.org>, Lee Jones <lee@...nel.org>, Jani Nikula <jani.nikula@...el.com>, 
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] mfd: intel_soc_pmic_crc: Use PWM_LOOKUP_WITH_MODULE() for
 the PWM lookup

On Thu, May 23, 2024 at 8:07 PM Hans de Goede <hdegoede@...hat.com> wrote:
>
> The primary use of the CRC PMIC's PWM is for LCD panel backlight
> control by the i915 driver.
>
> Due to its complexity the probe() function of the i915 driver does not
> support -EPROBE_DEFER handling. So far the pwm-crc driver must be built
> into the kernel to ensure that the pwm_get() done by the i915 driver
> succeeds at once (rather then returning -EPROBE_DEFER).
>
> But the PWM core can load the module from pwm_get() if a module-name is
> provided in the pwm_lookup associated with the consumer device.
>
> Switch to using PWM_LOOKUP_WITH_MODULE() for the lookup added for
> the Intel integrated GPU, so that the PWM core can load the module from
> pwm_get() as needed allowing the pwm-crc driver to be safely build as

built

> module.
>
> This has been successfully tested on an Asus T100TAM with pwm-crc
> build as module.

a module

Makes sense to me and it's good we allow better modularity as not all
x86-based products use Crystal Cove PMIC.
Reviewed-by: Andy Shevchenko <andy@...nel.org>

Thanks for this good patch!

-- 
With Best Regards,
Andy Shevchenko