Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 19 Jan 2022 09:49:30 +0300
From:   Andrey Skvortsov <andrej.skvortzov@gmail.com>
To:     Ulf Hansson <ulf.hansson@linaro.org>
Cc:     Arnaud Ferraris <arnaud.ferraris@gmail.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Avri Altman <avri.altman@wdc.com>,
        Shawn Lin <shawn.lin@rock-chips.com>,
        Huijin Park <huijin.park@samsung.com>,
        Christian =?utf-8?B?TMO2aGxl?= <CLoehle@hyperstone.com>,
        Yue Hu <huyue2@yulong.com>, linux-mmc@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mmc: core: Wait for command setting 'Power Off
 Notification' bit to complete
Message-ID: <Yee0ejAQeL+wSRsz@skv.local>
Mail-Followup-To: Andrey Skvortsov <andrej.skvortzov@gmail.com>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Arnaud Ferraris <arnaud.ferraris@gmail.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Avri Altman <avri.altman@wdc.com>,
        Shawn Lin <shawn.lin@rock-chips.com>,
        Huijin Park <huijin.park@samsung.com>,
        Christian =?utf-8?B?TMO2aGxl?= <CLoehle@hyperstone.com>,
        Yue Hu <huyue2@yulong.com>, linux-mmc@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20220115121447.641524-1-andrej.skvortzov@gmail.com>
 <CAPDyKFr_9kfAns2p6fsUck93s3peyrHvCtv5M9E3fnxLmHbRqQ@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <CAPDyKFr_9kfAns2p6fsUck93s3peyrHvCtv5M9E3fnxLmHbRqQ@mail.gmail.com>
Precedence: bulk

Hi, Ulf

On 22-01-18 19:48, Ulf Hansson wrote:
> On Sat, 15 Jan 2022 at 13:15, Andrey Skvortsov
> <andrej.skvortzov@gmail.com> wrote:
> >
> > SD card is allowed to signal busy on DAT0 up to 1s after the
> > CMD49. According to SD spec (version 6.0 section 5.8.1.3) first host
> > waits until busy of CMD49 is released and only then polls Power
> > Management Status register up to 1s until the card indicates ready to
> > power off.
> >
> > Without waiting for busy before polling status register sometimes card
> > becomes unresponsive and system fails to suspend:
> >
> >   [  205.907459] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
> >   [  206.421274] sunxi-mmc 1c0f000.mmc: data error, sending stop command
> >   [  206.421321] sunxi-mmc 1c0f000.mmc: send stop command failed
> >   [  206.421347] mmc0: error -110 reading status reg of PM func
> >   [  206.421366] PM: dpm_run_callback(): mmc_bus_suspend+0x0/0x74 returns -110
> >   [  206.421402] mmcblk mmc0:aaaa: PM: failed to suspend async: error -110
> >   [  206.437064] PM: Some devices failed to suspend, or early wake event detected
> 
> Thanks for your patch!
> 
> I recall I was hesitating on adding another busy completion check for
> this, but thought polling the status register for the power management
> function should be sufficient.
> 
> >
> > Tested with Sandisk Extreme PRO A2 64GB on Allwinner A64 system.
> 
> I will give this patch a try too, to make sure it still works on my
> side. Assuming that works fine, I will queue this up for fixes and by
> adding a fixes/stable tag.

Thank you! More testing would be certainly great, because only one of my SD-cards
supports "Power Notification".

-- 
Best regards,
Andrey Skvortsov