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] usb: host: xhci-plat: Iterate over parent nodes for
 finding quirks
To:     Anurag Kumar Vulisha <anuragku@xilinx.com>,
        Mathias Nyman <mathias.nyman@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
References: <1528212056-28390-1-git-send-email-anurag.kumar.vulisha@xilinx.com>
 <b819a5fc-82aa-dc9c-4272-fecdacbd5880@intel.com>
 <MWHPR02MB281619CD8CFDA93B9ADB3D89A7510@MWHPR02MB2816.namprd02.prod.outlook.com>
From:   Mathias Nyman <mathias.nyman@linux.intel.com>
Message-ID: <51566ca4-1002-5c62-71d0-9da610bff368@linux.intel.com>
Date:   Mon, 6 Aug 2018 13:50:38 +0300
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.7.0
MIME-Version: 1.0
In-Reply-To: <MWHPR02MB281619CD8CFDA93B9ADB3D89A7510@MWHPR02MB2816.namprd02.prod.outlook.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi,

Back from vacation

On 20.07.2018 18:39, Anurag Kumar Vulisha wrote:
> 
> Hi Mathias,
> 
> Thanks for providing your comments, please find my comments inline
> 
>>>
>>> -	if (device_property_read_bool(sysdev, "usb2-lpm-disable"))
>>> -		xhci->quirks |= XHCI_HW_LPM_DISABLE;
>>> +	/* Iterate over all parent nodes for finding quirks */
>>> +	for (tmpdev = &pdev->dev; tmpdev; tmpdev = tmpdev->parent) {
>>
>> Isn't sysdev at this point the topmost device that can have any of those device
>> properties set?
>> We could loop from &pdev->dev up to and including sysdev.
>>
>> It doesn't matter much but maybe avoid walking some extra parents.
>>> 
> I have seen some drivers ( like dwc3 host.c) which create a child dev, which is
> the pdev that is being passed to xhci_plat_probe(). So, sysdev may not be the
> topmost parent. There could be some properties which may be present in parent
> and may not be populated in the child. So, I made this change to search on all
> available parents for finding a valid property

Ok, lets keep it like you wrote it

> 
>>>
>>> -	if (device_property_read_bool(sysdev, "usb3-lpm-capable"))
>>> -		xhci->quirks |= XHCI_LPM_SUPPORT;
>>> +		if (device_property_read_bool(tmpdev, "usb2-lpm-disable"))
>>> +			xhci->quirks |= XHCI_HW_LPM_DISABLE;
>>>
>>> -	if (device_property_read_bool(&pdev->dev, "quirk-broken-port-ped"))
>>> -		xhci->quirks |= XHCI_BROKEN_PORT_PED;
>>> +		if (device_property_read_bool(tmpdev, "usb3-lpm-capable"))
>>> +			xhci->quirks |= XHCI_LPM_SUPPORT;
>>>
>>> -	/* imod_interval is the interrupt moderation value in nanoseconds. */
>>> -	xhci->imod_interval = 40000;
>>
>> Setting the default imod_interval could be moved before the for() loop
>>
> 
> I thought it would be better if everything related to imod_interval is in one place,
> so kept it as is. I can fix this in v2 if you suggest.

Default imod_interval needs to be set before the for loop to avoid overwriting a value
got from device property

So a v2 is needed

-Mathias