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Message-ID: <0dca7c9b-6a97-4171-9b0c-5b806a4e8a60@quicinc.com>
Date: Fri, 19 Apr 2024 07:17:32 +0800
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Subject: Re: [PATCH v1 1/2] Revert "Bluetooth: hci_qca: don't use
 IS_ERR_OR_NULL() with gpiod_get_optional()"
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        <luiz.dentz@gmail.com>, <luiz.von.dentz@intel.com>,
        <marcel@holtmann.org>
CC: <linux-bluetooth@vger.kernel.org>, <wt@penguintechs.org>,
        <bartosz.golaszewski@linaro.org>
References: <1713449192-25926-1-git-send-email-quic_zijuhu@quicinc.com>
 <1713449192-25926-2-git-send-email-quic_zijuhu@quicinc.com>
 <83a1c837-e403-4da2-83c6-ee3dedbc1fe0@linaro.org>
 <7c5b85ca-e897-4798-97e7-955478c57d12@quicinc.com>
 <52394d97-04c3-4f77-aaae-f1e152cd5632@linaro.org>
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From: quic_zijuhu <quic_zijuhu@quicinc.com>
In-Reply-To: <52394d97-04c3-4f77-aaae-f1e152cd5632@linaro.org>
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On 4/19/2024 6:37 AM, Krzysztof Kozlowski wrote:
> On 18/04/2024 23:16, quic_zijuhu wrote:
>> On 4/19/2024 12:52 AM, Krzysztof Kozlowski wrote:
>>> On 18/04/2024 16:06, Zijun Hu wrote:
>>>> This reverts commit 56d074d26c5828773b00b2185dd7e1d08273b8e8.
>>>>
>>>> Commit 56d074d26c58 ("Bluetooth: hci_qca: don't use IS_ERR_OR_NULL()
>>>> with gpiod_get_optional()") will cause serious regression issue for
>>>> several QCA controllers such as QCA_WCN6750,QCA_WCN6855,QCA_ROME,
>>>
>>> The pin is required on 6750, 6855 and maybe others. You cannot not have
>>> the GPIO.
>>>
>>> This is no correct fix. You provide wrong DTS and, instead fixing it,
>>> try to revert kernel code.
>>>
>>> No, fix your DTS first.
>>>
>> no. your point is not right.
>>
>> 1) do you have any evidence that the hci_qca driver must use reset GPIO?
> 
> I think we talk here about enable-gpios, right? Then the evidence are
> bindings.
> 
yes. properties within bindings only means driver supporting it, don't means user must
config it. the gpio is got by devm_gpiod_get_optional() variant. that means it is optional
about if user need to config it.
>> 2) why does original design do error return when get GPIO error if GPIO is mandatory?
> 
> If GPIO is mandatory, then it is expected to return error. What is the
> problem here?
> 
sorry, i miss a NOT for my question. my question is that
2) why does original design NOT do error return when get GPIO error if GPIO is mandatory?
> 
>> 3) i meet many customer cases that BT are working fine without hci_qca operating the GPIO,
>> there is why HCI_QUIRK_NON_PERSISTENT_SETUP are introduced.
> 
> Bindings tell different story and nothing in the commit msg explained
> this. You did not correct bindings either.
>
don't need to correct bindings. i believe bindings does not say enable gpio
must be configured.
>
>> 4) does the reverted change solve the issue your mentioned ?
> 
> ??? I did not mention any issue. I am saying that your rationale is
> either not complete or not correct.
> 
do you suggest about how to make it complete?

> Specifically, the enable-gpios ARE currently required, so whatever you
> claim here is not correct till they are required. Make them optional and
> then your arguments could have sense.
> 
> Best regards,
> Krzysztof
>