From:   Avri Altman <Avri.Altman@wdc.com>
To:     Nishad Kamdar <nishadkamdar@gmail.com>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Jens Axboe <axboe@kernel.dk>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Bean Huo <beanhuo@micron.com>,
        Shawn Lin <shawn.lin@rock-chips.com>,
        Stephen Boyd <swboyd@chromium.org>,
        Huijin Park <huijin.park@samsung.com>,
        Yue Hu <huyue2@yulong.com>,
        Wolfram Sang <wsa+renesas@sang-engineering.com>,
        =?iso-8859-1?Q?Christian_L=F6hle?= <CLoehle@hyperstone.com>
CC:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH] mmc: core: Add support for the eMMC RTC feature in
 mmc_ops
Thread-Topic: [PATCH] mmc: core: Add support for the eMMC RTC feature in
 mmc_ops
Thread-Index: AQHX6gvX/BT/iVXcEEKk0MhaGQh9w6wms6wQgAASTICAAABG4A==
Date:   Tue, 7 Dec 2021 09:33:46 +0000
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References: <20211205191009.32454-1-nishadkamdar@gmail.com>
 <DM6PR04MB657527FCF325EA9760032DA5FC6E9@DM6PR04MB6575.namprd04.prod.outlook.com>
 <20211207093009.GA11794@nishad>
In-Reply-To: <20211207093009.GA11794@nishad>
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> On Tue, Dec 07, 2021 at 08:28:42AM +0000, Avri Altman wrote:
> >
> > > This patch adds support to set the RTC information in the eMMC
> > > device. This is based on the JEDEC specification.
> > >
> > > There is no way however, to read the RTC time from the device. Hence
> > > we rely on the response of the CMD49 to confirm the completion of
> > > the operation.
> > >
> > > This patch has been tested successfully with the ioctl interface.
> > > This patch has also been tested suceessfully with all the three
> > > RTC_INFO_TYPEs.
> > If this is triggered from user-space via ioctl anyway, Why do we need
> > this command to be implemented in the kernel?
> > Why not just add this to mmc-utils?
> >
> > Thanks,
> > Avri
> As per the spec, B51: Section 6.6.35:
> Providing RTC info may be useful for internal maintainance operations.
> And the host should send it on the following events:
> - power-up
> - wake-up
> - Periodically
> Hence IMO, the Kernel would be the right place of peforming this operatio=
n.
But your patch doesn't do that, is it?

Thanks,
Avri