Received-SPF: pass (google.com: domain of linux-kernel+bounces-204600-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Message-ID: <3ab5357f-9577-4985-b09e-b686e66b7b5e@linaro.org>
Date: Thu, 6 Jun 2024 17:46:25 +0200
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v1] thermal: core: Do not fail cdev registration because
 of invalid initial state
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
 Linux PM <linux-pm@vger.kernel.org>, Linux ACPI
 <linux-acpi@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>,
 Lukasz Luba <lukasz.luba@arm.com>,
 Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
 Zhang Rui <rui.zhang@intel.com>, Laura Nao <laura.nao@collabora.com>
References: <4569763.LvFx2qVVIh@kreacher>
 <5f93f034-f781-47e0-b8ce-3c8407a709f7@linaro.org>
 <CAJZ5v0hkOvYL66D+tCRJxbp=XqV59yeZ0dA1Kxoczkcpe5X9sA@mail.gmail.com>
 <CAJZ5v0joTyOcRU0FyaHEEYEbiPbbNSFzW3P7eJJ4MM5QdhQR2w@mail.gmail.com>
 <90a9df3e-153f-4972-8086-13c21a574763@linaro.org>
 <CAJZ5v0jurx=TfT2GHCeMt7xhTFRQwpS_H6-fDss=bt+HodvBoQ@mail.gmail.com>
Content-Language: en-US
From: Daniel Lezcano <daniel.lezcano@linaro.org>
In-Reply-To: <CAJZ5v0jurx=TfT2GHCeMt7xhTFRQwpS_H6-fDss=bt+HodvBoQ@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit

On 06/06/2024 17:15, Rafael J. Wysocki wrote:

[ ... ]

> OK, so arguably the driver could set the initial state of the cooling
> device to 0.  That may or may not be the right thing to do depending
> on the thermal state of the system at the moment.  Then it would need
> to wait for the governor to pick up a more suitable state for it or
> leave it at 0.  This could address the particular case at hand.
> 
> However, should the core fail the cooling device registration if it
> gets an error from .get_cur_state() to start with?  It didn't do that
> before.  Indeed, it didn't even call .get_cur_state() then in the
> first place.  Moreover, the current state of the cooling device is not
> even needed to register it except for the initialization of the debug
> code for that cooling device, so why fail the registration of it?

Indeed, the simpler way would be to not register the debugfs if we can't 
get the initial cooling device state, with a message, so the driver 
responsible of that will appear and hopefully encourage someone to fix it.


-- 
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog