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Message-ID: <d77455b2-4fb9-4ffc-acf9-c24b5a0f4a45@quicinc.com>
Date: Wed, 24 Apr 2024 14:01:28 +0800
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Subject: Re: [PATCH v7 1/2] Bluetooth: qca: Fix BT enable failure for QCA6390
To: Wren Turkal <wt@penguintechs.org>,
        Krzysztof Kozlowski
	<krzysztof.kozlowski@linaro.org>,
        <luiz.dentz@gmail.com>, <luiz.von.dentz@intel.com>,
        <marcel@holtmann.org>
CC: <linux-bluetooth@vger.kernel.org>, <bartosz.golaszewski@linaro.org>,
        <regressions@lists.linux.dev>, <kernel@quicinc.com>,
        <gregkh@linuxfoundation.org>, <stable@vge.kernel.org>
References: <1713932807-19619-1-git-send-email-quic_zijuhu@quicinc.com>
 <1713932807-19619-2-git-send-email-quic_zijuhu@quicinc.com>
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 <067db05d-56bc-4ca3-aef1-bc3bae47667c@quicinc.com>
 <c1fc9c28-25df-4d41-9ae6-c5d079ea805d@penguintechs.org>
 <0db77c30-5be2-41b5-adf0-fb4436b9107b@quicinc.com>
 <c9bf22a3-2549-4cf1-898e-8a9adcd2f0f6@penguintechs.org>
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From: quic_zijuhu <quic_zijuhu@quicinc.com>
In-Reply-To: <c9bf22a3-2549-4cf1-898e-8a9adcd2f0f6@penguintechs.org>
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On 4/24/2024 1:49 PM, Wren Turkal wrote:
> On 4/23/24 10:46 PM, quic_zijuhu wrote:
>> On 4/24/2024 1:37 PM, Wren Turkal wrote:
>>> On 4/23/24 10:02 PM, quic_zijuhu wrote:
>>>> On 4/24/2024 12:30 PM, Krzysztof Kozlowski wrote:
>>>>> On 24/04/2024 06:26, Zijun Hu wrote:
>>>>>> Commit 56d074d26c58 ("Bluetooth: hci_qca: don't use IS_ERR_OR_NULL()
>>>>>> with gpiod_get_optional()") will cause below serious regression
>>>>>> issue:
>>>>>>
>>>>>> BT can't be enabled any more after below steps:
>>>>>> cold boot -> enable BT -> disable BT -> BT enable failure
>>>>>> if property enable-gpios is not configured within DT|ACPI for
>>>>>> QCA6390.
>>>>>>
>>>>>> The commit wrongly changes flag @power_ctrl_enabled set logic for
>>>>>> this
>>>>>> case as shown by its below code applet and causes this serious issue.
>>>>>> qcadev->bt_en = devm_gpiod_get_optional(&serdev->dev, "enable",
>>>>>>                                                  GPIOD_OUT_LOW);
>>>>>> - if (IS_ERR_OR_NULL(qcadev->bt_en)) {
>>>>>> + if (IS_ERR(qcadev->bt_en)) {
>>>>>>         dev_warn(&serdev->dev, "failed to acquire enable gpio\n");
>>>>>>      power_ctrl_enabled = false;
>>>>>>     }
>>>>>>
>>>>>> Fixed by reverting the mentioned commit for QCA6390.
>>>>>>
>>>>>> Fixes: 56d074d26c58 ("Bluetooth: hci_qca: don't use IS_ERR_OR_NULL()
>>>>>> with gpiod_get_optional()")
>>>>>> Cc: stable@vge.kernel.org
>>>>>> Reported-by: Wren Turkal <wt@penguintechs.org>
>>>>>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=218726
>>>>>> Link:
>>>>>> https://lore.kernel.org/linux-bluetooth/ea20bb9b-6b60-47fc-ae42-5eed918ad7b4@quicinc.com/T/#m73d6a71d2f454bb03588c66f3ef7912274d37c6f
>>>>>> Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
>>>>>> Tested-by: Wren Turkal <wt@penguintechs.org>
>>>>>> ---
>>>>>> Changes:
>>>>>> V6 -> V7: Add stable tag
>>>>>
>>>>> Stop sending multiple pathchsets per day. I already asked you to first
>>>>> finish discussion and then send new version. You again start sending
>>>>> something while previous discussion is going.
>>>>> you concern is wrong and i am sure it don't block me sending new patch
>>>> sets to solve other issue. so i send this v7.
>>>>
>>>> i have give reply for Bartosz' patch.
>>>>
>>>> i hop you as DTS expert to notice my concern about DTS in the reply.
>>>
>>> Are you saying here (1) that you identified a problem in the DTs that
>>> you hope Krzysztof notices or (2) that you want Krzysztof to notice how
>>> your description of way that DT declares the gpio as required affects
>>> your proposed change. As a native American English speaker, I am finding
>>> your text hard to follow.
>>>
>> 1) is my purpose. i have given my concern about DTS for Bartosz' patch
>> and hope DTS expert notice the concern.
>>
>> my change don't have any such concern about DTS usage. that is why i
>> changed my fix from original reverting the whole wrong commit to now
>> focusing on QCA6390.
> 
> Let me try to parse this. If #1 is the correct interpretation, does that
> mean that the DTs are wrong and need to be changed? Do you expect K to
> do that since he's the "DTS expert"?
> 
for your 1) question, NO
for your 2) question, need DTS expert notice or suggest how to handle
case that a DTS property is marked as required but not be configed by user.

>>> I think you are saying #2.
>>>
>>> I just want to make sure I am following the discussion here.
>>>
>>> wt
>>
>