Received: by 10.223.185.116 with SMTP id b49csp96349wrg;
        Thu, 8 Mar 2018 13:32:44 -0800 (PST)
X-Google-Smtp-Source: AG47ELt3GRgpUDupswBqAwiDj+EcnZr8mxmRedDkonfKeX1uqMny2ywU6c/sM8Fp0CodZgLRTfNI
X-Received: by 2002:a17:902:7885:: with SMTP id q5-v6mr17025695pll.207.1520544764592;
        Thu, 08 Mar 2018 13:32:44 -0800 (PST)
ARC-Seal: i=1; a=rsa-sha256; t=1520544764; cv=none;
        d=google.com; s=arc-20160816;
        b=S43BWBN+T9+bqib3Yrl7sp91r008dO7PhteJXGbMXZRMcYGSOmLHD3aR9gblhW5Y+x
         /VEYh1MwsSSN57Ojt5pa9dfhY5yMu7ILk+/p4F2ddhLmszJ3lsiNYc0FZcbcfXF7/FAL
         FWWLDSdLuDzLZtZJ2CR7blO1H8AHusi6e6MsAhccTtsjOf3tHHVLj0waApxV/FoSu+AR
         FwJREEB3Nvmx3gm6XSASNskYZhT7TIGUEPytkE82GfNE8Ay9TLZ615jD2u3rTMaBdhcq
         xMCUOLMxD7l8clYrfUGDuUG7FEfxxcTedprVfZouoJVcNzIhVVGBCixAwsom6azilC9A
         7scA==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
        h=list-id:precedence:sender:content-transfer-encoding
         :content-language:in-reply-to:mime-version:user-agent:date
         :message-id:from:references:cc:to:subject:arc-authentication-results;
        bh=TzQrw+MlCfzz6ukT7zT96vT08tnBQ0KDsVeL8I1IRak=;
        b=SIDdzp087EmuUyq3ahD4ss2AHy/QuRJtPhBDLtrwO26WnO0qVlyMhmuG/BT6jJB0K3
         rAL6t++cBcN+qFKBQEMfEf1qTdPyuL+h7ft4kE3BUxUAQruiR2bwkmOX9twiAQxA61zA
         PO1kXZ+793J3SlBmkzfjjQIbvDTwmJMJSs+IkmRvftcqrtegK4OdQqBzC3qbD5opViz3
         KYHVd8tCiW0S7DgQ+6DH3ataUEw+iSPQ/im36WCfIZnmTp/ZHjeZKCzggVGcyDpeAa0o
         UANs+GyxxpAyEmUTHeAs+hRC5oZCvzNMUdxGyFwMauvW9SAelIpoxdMOTTvZTFB0SDUA
         3+JA==
ARC-Authentication-Results: i=1; mx.google.com;
       spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org;
       dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=nvidia.com
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67])
        by mx.google.com with ESMTP id m3-v6si15407827plb.480.2018.03.08.13.32.29;
        Thu, 08 Mar 2018 13:32:44 -0800 (PST)
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;
Authentication-Results: mx.google.com;
       spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org;
       dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=nvidia.com
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1751083AbeCHVbO convert rfc822-to-8bit (ORCPT
        <rfc822;arandomawesomegeek@gmail.com> + 99 others);
        Thu, 8 Mar 2018 16:31:14 -0500
Received: from hqemgate16.nvidia.com ([216.228.121.65]:8947 "EHLO
        hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1750728AbeCHVbM (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Thu, 8 Mar 2018 16:31:12 -0500
Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate16.nvidia.com
        id <B5aa1ab9e0001>; Thu, 08 Mar 2018 13:31:10 -0800
Received: from HQMAIL104.nvidia.com ([172.20.161.6])
  by hqpgpgate101.nvidia.com (PGP Universal service);
  Thu, 08 Mar 2018 13:31:11 -0800
X-PGP-Universal: processed;
        by hqpgpgate101.nvidia.com on Thu, 08 Mar 2018 13:31:11 -0800
Received: from UKMAIL101.nvidia.com (10.26.138.13) by HQMAIL104.nvidia.com
 (172.18.146.11) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Thu, 8 Mar
 2018 21:31:10 +0000
Received: from [10.26.11.23] (10.26.11.23) by UKMAIL101.nvidia.com
 (10.26.138.13) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Thu, 8 Mar
 2018 21:31:07 +0000
Subject: Re: [PATCH 2/3] usb: xhci: tegra: Add runtime PM support
To:     Mathias Nyman <mathias.nyman@linux.intel.com>,
        Mathias Nyman <mathias.nyman@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Thierry Reding <thierry.reding@gmail.com>
CC:     <linux-usb@vger.kernel.org>, <linux-tegra@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <1518626085-29102-1-git-send-email-jonathanh@nvidia.com>
 <1518626085-29102-2-git-send-email-jonathanh@nvidia.com>
 <54bd00b7-2835-a253-0399-370e8c8203b8@linux.intel.com>
From:   Jon Hunter <jonathanh@nvidia.com>
Message-ID: <f1a1c300-a558-f31a-bcfa-c3eda697b0fd@nvidia.com>
Date:   Thu, 8 Mar 2018 21:31:07 +0000
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: <54bd00b7-2835-a253-0399-370e8c8203b8@linux.intel.com>
X-Originating-IP: [10.26.11.23]
X-ClientProxiedBy: UKMAIL102.nvidia.com (10.26.138.15) To UKMAIL101.nvidia.com
 (10.26.138.13)
Content-Type: text/plain; charset="utf-8"
Content-Language: en-US
Content-Transfer-Encoding: 8BIT
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org


On 01/03/18 14:18, Mathias Nyman wrote:
> On 14.02.2018 18:34, Jon Hunter wrote:
>> Add runtime PM support to the Tegra XHCI driver and move the function
>> calls to enable/disable the clocks, regulators and PHY into the runtime
>> PM callbacks.
>>
>> Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
>> ---
>>   drivers/usb/host/xhci-tegra.c | 80
>> ++++++++++++++++++++++++++++++-------------
>>   1 file changed, 56 insertions(+), 24 deletions(-)
>>
>> diff --git a/drivers/usb/host/xhci-tegra.c
>> b/drivers/usb/host/xhci-tegra.c
>> index 02b0b24faa58..42aa67858b53 100644
>> --- a/drivers/usb/host/xhci-tegra.c
>> +++ b/drivers/usb/host/xhci-tegra.c
>> @@ -18,6 +18,7 @@
>>   #include <linux/phy/tegra/xusb.h>
>>   #include <linux/platform_device.h>
>>   #include <linux/pm.h>
>> +#include <linux/pm_runtime.h>
>>   #include <linux/regulator/consumer.h>
>>   #include <linux/reset.h>
>>   #include <linux/slab.h>
>> @@ -1067,22 +1068,12 @@ static int tegra_xusb_probe(struct
>> platform_device *pdev)
>>        */
>>       platform_set_drvdata(pdev, tegra);
>>   -    err = tegra_xusb_clk_enable(tegra);
>> -    if (err) {
>> -        dev_err(&pdev->dev, "failed to enable clocks: %d\n", err);
>> -        goto put_usb2;
>> -    }
>> -
>> -    err = regulator_bulk_enable(tegra->soc->num_supplies,
>> tegra->supplies);
>> -    if (err) {
>> -        dev_err(&pdev->dev, "failed to enable regulators: %d\n", err);
>> -        goto disable_clk;
>> -    }
>> +    pm_runtime_enable(&pdev->dev);
>>   -    err = tegra_xusb_phy_enable(tegra);
>> +    err = pm_runtime_get_sync(&pdev->dev);
>>       if (err < 0) {
> 
> Does this mean that if runtime PM is disabled then clocks and regulator
> will never be enabled
> for Tegra xhci?
> 
> How about keeping the clock and regualtor enabling in probe, and instead
> add something like:
> 
> pm_runtime_set_active(&pdev->dev);
> pm_runtime_enable(&pdev->dev);
> pm_runtime_get_noresume(&pdev->dev);

For 64-bit Tegra there is a dependency on CONFIG_PM, but for 32-bit
AFAIK there is not and so yes we should handle the case when PM_RUNTIME
is disabled.

Typically we do something like ...

    pm_runtime_enable(&pdev->dev);
    if (!pm_runtime_enabled(&pdev->dev))
	ret = tegra_xusb_runtime_resume(&pdev->dev);
    else
        ret = pm_runtime_get_sync(&pdev->dev);

That way we can keep the regulator and clock stuff in the handler. I
will update this series.

Cheers
Jon

-- 
nvpublic