Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH v2 RESEND] usb: dwc3: core: Fix ULPI PHYs and prevent
 phy_get/ulpi_init during suspend/resume
From:   Todor Tomov <todor.tomov@linaro.org>
To:     Felipe Balbi <balbi@kernel.org>
Cc:     Roger Quadros <rogerq@ti.com>, linux-usb@vger.kernel.org,
        vigneshr@ti.com, gregkh@linuxfoundation.org,
        linux-kernel@vger.kernel.org,
        "linux-stable # = v4 . 13" <stable@vger.kernel.org>
References: <1515667087-4110-1-git-send-email-rogerq@ti.com>
 <ee73347b-e996-4052-6a9d-dd94edd4a61a@ti.com>
 <606dbc68-2014-8590-ce47-83c175d4cd41@linaro.org>
 <87efbm92zi.fsf@linux.intel.com>
 <027608c0-8d2d-42ab-5125-76b86f286d2b@linaro.org>
Message-ID: <08ebcaea-45c4-d277-9585-97045960e83a@linaro.org>
Date:   Mon, 26 Nov 2018 10:27:50 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.6.0
MIME-Version: 1.0
In-Reply-To: <027608c0-8d2d-42ab-5125-76b86f286d2b@linaro.org>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Felipe,

On 16.11.2018 19:01, Todor Tomov wrote:
> Hi,
> 
> On 15.11.2018 10:09, Felipe Balbi wrote:
>>
>> Hi,
>>
>> Todor Tomov <todor.tomov@linaro.org> writes:
>>
>>> Hello,
>>>
>>> After I apply this patch on 4.14 (or receive it with 4.14.70) I see a regression with
>>> the Qualcomm QUSB2 phy driver. I'm testing on a Dragonboard 820c.
>>> In boot log I get:
>>>
>>> [    4.525502] phy phy-7412000.phy.6: QUSB2PHY pll lock failed: status reg = 0
>>> [    4.529232] phy phy-7412000.phy.6: phy init failed --> -16
>>> [    4.536170] dwc3 7600000.dwc3: failed to initialize core
>>> [    4.541743] dwc3: probe of 7600000.dwc3 failed with error -16
>>> [    4.549979] phy phy-7411000.phy.5: QUSB2PHY pll lock failed: status reg = 0
>>> [    4.552843] phy phy-7411000.phy.5: phy init failed --> -16
>>> [    4.559606] dwc3 6a00000.dwc3: failed to initialize core
>>> [    4.565181] dwc3: probe of 6a00000.dwc3 failed with error -16
>>>
>>> I can provide a full log if needed.
>>
>> please do. Also, try mainline and let us know if the problem
> 
> This is the full log on 4.14.69 + this patch: https://paste.ubuntu.com/p/N5WdHw47QC/
> I also managed to get a log from 4.20.0-rc2 and I see the same error: https://paste.udwc3_phy_setupbuntu.com/p/jz6fvYyZh6/
> 
>> persists. Why do you get -EBUSY from the PHY driver?
> 
> Maybe I could have proposed a fix if I knew but I don't know.

I have done some debugging but I still cannot understand it completely.

What I see is that if the PHY interface is configured first (dwc3_phy_setup)
then the PHY init (qusb2_phy_init called by dwc3_core_soft_reset) fails
with "pll lock failed". If we move dwc3_phy_setup after dwc3_core_soft_reset
as it was before this patch, it works.

Do you have any ideas why this happens or how to solve it?

Thank you.
Best regards,
Todor