Re: [PATCH] Bluetooth: qca: set power_ctrl_enabled on NULL returned by gpiod_get_optional()

From: Wren Turkal <wt@penguintechs.org>
To: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>,
	linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org,
	Zijun Hu <quic_zijuhu@quicinc.com>,
	Marcel Holtmann <marcel@holtmann.org>,
	Luiz Augusto von Dentz <luiz.dentz@gmail.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Subject: Re: [PATCH] Bluetooth: qca: set power_ctrl_enabled on NULL returned by gpiod_get_optional()
Date: Wed, 24 Apr 2024 05:24:19 -0700	[thread overview]
Message-ID: <4c33304a-5dbc-450a-b874-e04ba9e93150@penguintechs.org> (raw)
In-Reply-To: <CACMJSeunUaj0cxLaN4MpFmX5vTOx_vnWjBN4Y2FavdQoQxFRkg@mail.gmail.com>

On 4/24/24 5:20 AM, Bartosz Golaszewski wrote:
> On Wed, 24 Apr 2024 at 14:17, Wren Turkal <wt@penguintechs.org> wrote:
>>
>> On 4/24/24 4:56 AM, Bartosz Golaszewski wrote:
>>> On Wed, Apr 24, 2024 at 1:53 PM Wren Turkal <wt@penguintechs.org> wrote:
>>>>
>>>> On 4/24/24 4:16 AM, Wren Turkal wrote:
>>>>> On 4/24/24 2:04 AM, Bartosz Golaszewski wrote:
>>>>>> On Wed, 24 Apr 2024 07:07:05 +0200, Wren Turkal<wt@penguintechs.org>
>>>>>> said:
>>>>>>> On 4/22/24 6:00 AM, Bartosz Golaszewski wrote:
>>>>>>>> From: Bartosz Golaszewski<bartosz.golaszewski@linaro.org>
>>>>>>>>
>>>>>>>> Any return value from gpiod_get_optional() other than a pointer to a
>>>>>>>> GPIO descriptor or a NULL-pointer is an error and the driver should
>>>>>>>> abort probing. That being said: commit 56d074d26c58 ("Bluetooth:
>>>>>>>> hci_qca:
>>>>>>>> don't use IS_ERR_OR_NULL() with gpiod_get_optional()") no longer sets
>>>>>>>> power_ctrl_enabled on NULL-pointer returned by
>>>>>>>> devm_gpiod_get_optional(). Restore this behavior but bail-out on
>>>>>>>> errors.
>>>>>>> Nack. This patch does fixes neither the disable/re-enable problem nor
>>>>>>> the warm boot problem.
>>>>>>>
>>>>>>> Zijun replied to this patch also with what I think is the proper
>>>>>>> reasoning for why it doesn't fix my setup.
>>>>>>>
>>>>>> Indeed, I only addressed a single issue here and not the code under the
>>>>>> default: label of the switch case. Sorry.
>>>>>>
>>>>>> Could you give the following diff a try?
>>>>>
>>>>> I had a feeling that was what was going on. I'll give the patch a shot.
>>>>>
>>>>> wt
>>>>
>>>> Considering this patch is basically equivalent to patch 1/2 from Zijun,
>>>> I am not surprised that is works similarly. I.e. on a cold boot, I can
>>>> disable/re-enable bluetooth as many time as I want.
>>>>
>>>
>>> Zijun didn't bail out on errors which is the issue the original patch
>>> tried to address and this one preserves.
>>>
>>>> However, since this patch doesn't include the quirk fix from Zijun's
>>>> patchset (patch 2/2), bluetooth fails to work after a warm boot.
>>>>
>>>
>>> That's OK, we have the first part right. Let's now see if we can reuse
>>> patch 2/2 from Zijun.
>>
>> I'm compiling it right now. Be back soon.
>>
> 
> Well I doubt it's correct as it removed Krzysztof's fix which looks
> right. If I were to guess I'd say we need some mix of both.

Patch 2/2 remove K's fix? I thought only 1/2 did that.

To be specific, I have applied your patch and Zijun's 2/2 only.

> Bart
> 
>>>> @Zijun, this patch looks more idiomatic when I look at the surrounding
>>>> code than your patch 1/2. Notice how it doesn't use the "else if"
>>>> construct. It does the NULL test separately after checking for errors.
>>>>
>>>> --
>>>> You're more amazing than you think!
>>>
>>> Bart
>>
>> --
>> You're more amazing than you think!

-- 
You're more amazing than you think!