Re: [PATCH 0/2] Enable GPIO and I2C configs for TI's J721e platform

[Tero Kristo]

On 08/10/2020 11:59, Faiz Abbas wrote:
> Tero,
>
> On 06/10/20 6:40 pm, Tero Kristo wrote:
> > On 06/10/2020 16:03, Faiz Abbas wrote:
> > > Hi Tero,
> > >
> > > On 06/10/20 5:21 pm, Tero Kristo wrote:
> > > > On 02/10/2020 19:45, Faiz Abbas wrote:
> > > > > The following patches enable configs in the arm64 defconfig to support
> > > > > GPIO and I2C support on TI's J721e platform.
> > > > >
> > > > > Faiz Abbas (2):
> > > > >      arm64: defconfig: Enable OMAP I2C driver
> > > > >      arm64: defconfig: Enable DAVINCI_GPIO driver
> > > > >
> > > > >     arch/arm64/configs/defconfig | 2 ++
> > > > >     1 file changed, 2 insertions(+)
> > > >
> > > > Why are you enabling these?
> > > >
> > > > Are they required for booting the board?
> > > >
> > > > If not, they shall not be enabled, as it just clutters the arm64 defconfig unnecessarily.
> > >
> > > They are required because the SD card regulators need gpio over i2c expander and also
> > > soc gpio support to come up in UHS modes.
> >
> > Is that needed for boot support? If it is only needed with UHS cards, that does not seem important enough for me. We can already boot the board via other means.
>
> Without these configs, the regulator drivers keep EPROBE_DEFERing waiting for their gpio drivers
> to probe and SD card never comes up. This configuration happens before any UHS capabilities are detected.
>
> [    1.326654] sdhci-am654 4fb0000.sdhci: _devm_regulator_get id:vmmc ret:-517
> [    1.333651] sdhci-am654 4fb0000.sdhci: _devm_regulator_get id:vqmmc ret:-517
> [    1.340693] sdhci-am654 4fb0000.sdhci: sdhci_am654_probe ret:-517
> [    1.489088] sdhci-am654 4fb0000.sdhci: _devm_regulator_get id:vmmc ret:-517
> [    1.496067] sdhci-am654 4fb0000.sdhci: _devm_regulator_get id:vqmmc ret:-517
> [    1.510392] sdhci-am654 4fb0000.sdhci: sdhci_am654_probe ret:-517
> [    1.543210] sdhci-am654 4fb0000.sdhci: _devm_regulator_get id:vmmc ret:-517
> [    1.550186] sdhci-am654 4fb0000.sdhci: _devm_regulator_get id:vqmmc ret:-517
> [    1.568134] sdhci-am654 4fb0000.sdhci: sdhci_am654_probe ret:-517

This happens because you have merged/enabled UHS support or? This sounds 
like a regression as I haven't seen this happen before.

-Tero
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