From: Ulf Hansson <ulf.hansson@linaro.org>
To: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Shawn Guo <shawnguo@kernel.org>,
Sascha Hauer <s.hauer@pengutronix.de>,
Sascha Hauer <kernel@pengutronix.de>,
Fabio Estevam <festevam@gmail.com>,
dl-linux-imx <linux-imx@nxp.com>,
Wolfram Sang <wsa+renesas@sang-engineering.com>,
Doug Anderson <dianders@chromium.org>,
Rui Miguel Silva <rmfrfs@gmail.com>, Chris Ball <cjb@laptop.org>,
Linux ARM <linux-arm-kernel@lists.infradead.org>,
linux-mmc <linux-mmc@vger.kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] mmc: mxs-mmc: Disable the 'reg_vmmc' regulator when needed
Date: Wed, 26 May 2021 00:47:54 +0200 [thread overview]
Message-ID: <CAPDyKFptO4PRc=kxd9k8CkofGfyfJB6pdxP-wzrNpSHv0+ya0Q@mail.gmail.com> (raw)
In-Reply-To: <7c973bfd-8fc3-026d-351c-dc00e92c8b01@wanadoo.fr>
On Tue, 25 May 2021 at 21:31, Christophe JAILLET
<christophe.jaillet@wanadoo.fr> wrote:
>
> Le 24/05/2021 à 15:59, Ulf Hansson a écrit :
> > On Fri, 21 May 2021 at 14:36, Christophe JAILLET
> > <christophe.jaillet@wanadoo.fr> wrote:
> >>
> >> The 'reg_vmmc' regulator is never disabled. Neither in the error handling
> >> of the probe, nor in the remove function.
> >>
> >> Add a managed action to do the required clean-up before a 'regulator_put()'
> >> call.
> >>
> >> Fixes: 4dc5a79f1350 ("mmc: mxs-mmc: enable regulator for mmc slot")
> >> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> >> ---
> >> drivers/mmc/host/mxs-mmc.c | 11 +++++++++++
> >> 1 file changed, 11 insertions(+)
> >>
> >> diff --git a/drivers/mmc/host/mxs-mmc.c b/drivers/mmc/host/mxs-mmc.c
> >> index 947581de7860..b043d53dd728 100644
> >> --- a/drivers/mmc/host/mxs-mmc.c
> >> +++ b/drivers/mmc/host/mxs-mmc.c
> >> @@ -552,6 +552,13 @@ static const struct of_device_id mxs_mmc_dt_ids[] = {
> >> };
> >> MODULE_DEVICE_TABLE(of, mxs_mmc_dt_ids);
> >>
> >> +static void regulator_disable_action(void *_data)
> >> +{
> >> + struct regulator *regulator = _data;
> >> +
> >> + regulator_disable(regulator);
> >> +}
> >> +
> >> static int mxs_mmc_probe(struct platform_device *pdev)
> >> {
> >> struct device_node *np = pdev->dev.of_node;
> >> @@ -591,6 +598,10 @@ static int mxs_mmc_probe(struct platform_device *pdev)
> >> "Failed to enable vmmc regulator: %d\n", ret);
> >> goto out_mmc_free;
> >> }
> >> + ret = devm_add_action_or_reset(&pdev->dev,
> >> + regulator_disable_action, reg_vmmc);
> >> + if (ret)
> >> + goto out_mmc_free;
> >
> > Even if this improves the behaviour, there is a standardized way for
> > how we deal with regulators for mmc.
> >
> > 1. Call mmc_regulator_get_supply() during probe to fetch the optional
> > regulator. If a regulator is found a corresponding OCR mask, in
> > host->ocr_avail is assigned.
> >
> > 2. In the ->set_ios() callback, invoke mmc_regulator_set_ocr(). This
> > will also set the correct voltage-level and turn on/off the regulator,
> > depending on the requested OCR/voltage-level.
>
> Hi,
> I don't know this API.
> I've tried to look at a few drivers to see how it was used, but it
> didn't help me either.
Okay.
>
> So, I won't be able to provide any other proposal on this. It would only
> be trial/error.
> It is yours if something needs to be fixed here.
>
> Anyway, thanks for your time for answering and trying to show the right
> direction.
If I put together some patch and submit it, would you be able help to
run some tests of it, as I don't have access to HW?
Kind regards
Uffe
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-05-25 22:51 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-21 12:36 [PATCH] mmc: mxs-mmc: Disable the 'reg_vmmc' regulator when needed Christophe JAILLET
2021-05-24 13:59 ` Ulf Hansson
2021-05-25 19:31 ` Christophe JAILLET
2021-05-25 22:47 ` Ulf Hansson [this message]
2021-05-26 7:46 ` Christophe JAILLET
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CAPDyKFptO4PRc=kxd9k8CkofGfyfJB6pdxP-wzrNpSHv0+ya0Q@mail.gmail.com' \
--to=ulf.hansson@linaro.org \
--cc=christophe.jaillet@wanadoo.fr \
--cc=cjb@laptop.org \
--cc=dianders@chromium.org \
--cc=festevam@gmail.com \
--cc=kernel-janitors@vger.kernel.org \
--cc=kernel@pengutronix.de \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-imx@nxp.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mmc@vger.kernel.org \
--cc=rmfrfs@gmail.com \
--cc=s.hauer@pengutronix.de \
--cc=shawnguo@kernel.org \
--cc=wsa+renesas@sang-engineering.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).