Received-SPF: pass (google.com: domain of linux-kernel+bounces-189404-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Precedence: bulk
MIME-Version: 1.0
References: <20240523170745.92166-1-hdegoede@redhat.com>
In-Reply-To: <20240523170745.92166-1-hdegoede@redhat.com>
From: Andy Shevchenko <andy.shevchenko@gmail.com>
Date: Sat, 25 May 2024 17:52:23 +0300
Message-ID: <CAHp75VcYk_7Wb2bas2Z0db3gsCQL5Qp2sKzj=sJjp_WdHxoRpg@mail.gmail.com>
Subject: Re: [PATCH] mfd: intel_soc_pmic_crc: Use PWM_LOOKUP_WITH_MODULE() for
 the PWM lookup
To: Hans de Goede <hdegoede@redhat.com>
Cc: Andy Shevchenko <andy@kernel.org>, Lee Jones <lee@kernel.org>, Jani Nikula <jani.nikula@intel.com>, 
	linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Thu, May 23, 2024 at 8:07=E2=80=AFPM Hans de Goede <hdegoede@redhat.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@kernel.org>

Thanks for this good patch!

--=20
With Best Regards,
Andy Shevchenko