On 20-10-21 07:49, Uwe Kleine-König wrote: > 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, > > > > > > > > > > On 20-10-20 13:15, Uwe Kleine-König wrote: > > > > > > Instead of just ignoring errors related to regulator getting error 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. > > > > > > > > > > > > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> > > > > > > --- > > > > > > drivers/usb/imx/chipidea-imx.c | 7 +++++-- > > > > > > 1 file changed, 5 insertions(+), 2 deletions(-) > > > > > > > > > > > > diff --git a/drivers/usb/imx/chipidea-imx.c b/drivers/usb/imx/chipidea-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) > > > > > > } > > > > > > > > > > > > ci->vbus = regulator_get(dev, "vbus"); > > > > > > - if (IS_ERR(ci->vbus)) > > > > > > - ci->vbus = NULL; > > > > > > + if (IS_ERR(ci->vbus)) { > > > > > > + ret = ERR_PTR(ci->vbus); > > > > > > + dev_err(dev, "Cannot get vbus regulator: %s\n", strerror(-ret)); > > > > > > + return ret; > > > > > > > > > > Returning the error here can cause problems with exisiting boards, e.g. > > > > > if the regulator support is missing for the specified vbus regulator. > > > > > This is often the case since we have very limited regulator support for > > > > > now. > > > > > > > > But when there is a regulator we also have to control it, right? > > > > > > 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. Adding a warining seems valid to me but returning a error is wrong since the mainline driver explicite says: "/* no vbus regulator is needed */". > > > 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 > > > 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 @@ > }; > > &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; > }; > > > > > this patch, just wanted to show the consequences of it. > > > > Sorry I have to correct myself, pls check the linux driver: > > > > static int ci_get_platdata(struct device *dev, > > struct ci_hdrc_platform_data *platdata) > > { > > > > ... > > > > /* Get the vbus regulator */ > > platdata->reg_vbus = devm_regulator_get_optional(dev, "vbus"); > > if (PTR_ERR(platdata->reg_vbus) == -EPROBE_DEFER) { > > return -EPROBE_DEFER; > > } else if (PTR_ERR(platdata->reg_vbus) == -ENODEV) { > > /* no vbus regulator is needed */ > > platdata->reg_vbus = 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. Nope, regulator_get returns dummy-regulators too and -ENODEV is returned in case of regulator_get_optional() too, pls. check: /* Internal regulator request function */ struct regulator *_regulator_get(struct device *dev, const char *id, enum regulator_get_type get_type) { ... } Regards, Marco > (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 = 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"); > > > and then it is more obvious that my barebox patch does the same. > > Am I missing something? > > Best regards > Uwe > > -- > Pengutronix e.K. | Uwe Kleine-König | > Industrial Linux Solutions | https://www.pengutronix.de/ | > _______________________________________________ > barebox mailing list > barebox@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/barebox -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox