From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kV6zl-0000cS-PT for barebox@lists.infradead.org; Wed, 21 Oct 2020 05:49:10 +0000 Date: Wed, 21 Oct 2020 07:49:07 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= Message-ID: <20201021054907.sunblqmijd4jl6zn@pengutronix.de> References: <20201020111537.29328-1-u.kleine-koenig@pengutronix.de> <20201020133317.dc6yt2yt4tyk5ogm@pengutronix.de> <20201020140934.GS13710@pengutronix.de> <20201020142806.kmxoy6byavdwe5cv@pengutronix.de> <20201020145844.4id6iyuihl3hkt3x@pengutronix.de> MIME-Version: 1.0 In-Reply-To: <20201020145844.4id6iyuihl3hkt3x@pengutronix.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============2982877634790720814==" Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH] usb: i.MX: improve regulator handling To: Marco Felsch Cc: barebox@lists.infradead.org --===============2982877634790720814== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="h5pvzwvmeoqaobpa" Content-Disposition: inline --h5pvzwvmeoqaobpa Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Oct 20, 2020 at 04:58:44PM +0200, Marco Felsch wrote: > On 20-10-20 16:28, Marco Felsch wrote: > > On 20-10-20 16:09, Sascha Hauer wrote: > > > On Tue, Oct 20, 2020 at 03:33:17PM +0200, Marco Felsch wrote: > > > > Hi Uwe, > > > >=20 > > > > On 20-10-20 13:15, Uwe Kleine-K=F6nig wrote: > > > > > Instead of just ignoring errors related to regulator getting erro= r out. > > > > > In case there is no regulator in the device tree, regulator_get()= returns > > > > > the dummy regulator and not an error code, so the change is right= for > > > > > this situation, too. > > > > >=20 > > > > > Signed-off-by: Uwe Kleine-K=F6nig > > > > > --- > > > > > drivers/usb/imx/chipidea-imx.c | 7 +++++-- > > > > > 1 file changed, 5 insertions(+), 2 deletions(-) > > > > >=20 > > > > > diff --git a/drivers/usb/imx/chipidea-imx.c b/drivers/usb/imx/chi= pidea-imx.c > > > > > index 786beede6d89..dd0e3c1a2a58 100644 > > > > > --- a/drivers/usb/imx/chipidea-imx.c > > > > > +++ b/drivers/usb/imx/chipidea-imx.c > > > > > @@ -267,8 +267,11 @@ static int imx_chipidea_probe(struct device_= d *dev) > > > > > } > > > > > =20 > > > > > ci->vbus =3D regulator_get(dev, "vbus"); > > > > > - if (IS_ERR(ci->vbus)) > > > > > - ci->vbus =3D NULL; > > > > > + if (IS_ERR(ci->vbus)) { > > > > > + ret =3D ERR_PTR(ci->vbus); > > > > > + dev_err(dev, "Cannot get vbus regulator: %s\n", strerror(-ret)= ); > > > > > + return ret; > > > >=20 > > > > Returning the error here can cause problems with exisiting boards, = e.g. > > > > if the regulator support is missing for the specified vbus regulato= r. > > > > This is often the case since we have very limited regulator support= for > > > > now. > > >=20 > > > But when there is a regulator we also have to control it, right? > >=20 > > So you need to add each regulator driver or worst case you need to add > > PMIC drivers. Right, as if you don't the hardware might be off and USB won't work without a useful error message. > > If I remember correctly, I added the same for mci which > > broke a lot of boards. Later you reverted those commit. Now Oleksij > > added the regulator support for the fec driver and people are starting= =20 > > to remove the phy-supply handle from the barebox-dt's (commit 84cf5cfa9a > > ("ARM: dts: imx6qdl: pfla02: Remove fec phy-supply")). I'm not again Looking at 84cf5cfa9a there is at least a comment missing about why this property is deleted. Something like diff --git a/arch/arm/dts/imx6qdl-phytec-pfla02.dtsi b/arch/arm/dts/imx6qdl= -phytec-pfla02.dtsi index b83511cb011f..7a12e2a06be4 100644 --- a/arch/arm/dts/imx6qdl-phytec-pfla02.dtsi +++ b/arch/arm/dts/imx6qdl-phytec-pfla02.dtsi @@ -84,6 +84,11 @@ }; =20 &fec { + /* + * barebox doesn't have a driver for the PMIC providing the phy-supply + * (dlg,da9063). So remove the phy-supply property and rely on the + * PMIC's reset default which has this supply enabled. + */ /delete-property/ phy-supply; }; =20 > > this patch, just wanted to show the consequences of it. >=20 > Sorry I have to correct myself, pls check the linux driver: >=20 > static int ci_get_platdata(struct device *dev, > struct ci_hdrc_platform_data *platdata) > { >=20 > ... >=20 > /* Get the vbus regulator */ > platdata->reg_vbus =3D devm_regulator_get_optional(dev, "vbus"); > if (PTR_ERR(platdata->reg_vbus) =3D=3D -EPROBE_DEFER) { > return -EPROBE_DEFER; > } else if (PTR_ERR(platdata->reg_vbus) =3D=3D -ENODEV) { > /* no vbus regulator is needed */ > platdata->reg_vbus =3D NULL; > } else if (IS_ERR(platdata->reg_vbus)) { > dev_err(dev, "Getting regulator error: %ld\n", > PTR_ERR(platdata->reg_vbus)); > return PTR_ERR(platdata->reg_vbus); > } The difference between regulator_get and regulator_get_optional is that the former doesn't return -ENODEV but yields the dummy regulator instead. (Yes, this is the inversed semantic compared with gpio_get_optional() and clk_get_optional().) So using devm_regulator_get_optional and ignoring -ENODEV is kind of strange. So I think the above can be simplified to: platdata->reg_vbus =3D devm_regulator_get(dev, "vbus"); if (IS_ERR(platdata->reg_vbus)) return dev_err_probe(dev, PTR_ERR(platdata->reg_vbus), "Failed to get vbus regulator\n"); =09 and then it is more obvious that my barebox patch does the same. Am I missing something? Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | https://www.pengutronix.de/ | --h5pvzwvmeoqaobpa Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEfnIqFpAYrP8+dKQLwfwUeK3K7AkFAl+Py9AACgkQwfwUeK3K 7Akr4wf/fpxyMr9ez2VqE1twzTXFf5A0cBpJsS1+eWbgH6HnJhktfO3ebDQ/n8iO oQayqpGZGZF8HTJ+IFuiJV/O4JLuCWppb2PsTdXMVLnTznvb3SSSYeVK5vFIAkdC 3VVNlLqCmzBhBjLiIT9/KJkOZaGphWPcU0GSEOh/pmpS6pdwRp/6peUn9M52NWQ3 izGIk2wKwihLRw3LjzNS7IG36+qzFiiQHtP+n+VWlyf8Y7eEmCF13tf5c3e4KP+S ArdMsJVYA+j/3rkZZogzhh3gR3wJH+6JQIe+1hFwkHoQNA4mElLgqWt2ZAJMjWCi +CQARDD2jhWRh6vVF3x8j+js6cEo+Q== =O3M7 -----END PGP SIGNATURE----- --h5pvzwvmeoqaobpa-- --===============2982877634790720814== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox --===============2982877634790720814==--