[Linux-stm32] [PATCH 1/3] mmc: Prepare all code for mmc_set_signal_voltage() returning > 0

[Ulf Hansson]

On Thu, 16 Apr 2020 at 12:29, Marek Vasut <marex at denx.de> wrote:
>
> On 4/15/20 10:40 AM, Ulf Hansson wrote:
> > On Wed, 1 Apr 2020 at 21:57, Marek Vasut <marex at denx.de> wrote:
> >>
> >> Patch all drivers and core code which uses mmc_set_signal_voltage()
> >> and prepare it for the fact that mmc_set_signal_voltage() can return
> >> a value > 0, which would happen if the signal voltage switch did NOT
> >> happen, because the voltage was already set correctly.
> >
> > I am not sure why you want to change mmc_set_signal_voltage(), can you
> > elaborate on that?
> >
> > I thought we discussed changing mmc_regulator_set_vqmmc(), what am I missing?
>
> Because mmc_set_signal_voltage() optionally calls
> host->ops_>start_signal_voltage_switch() , which can now return value >
> 0 , so the rest of the core needs to be patched to cater for that.

The issue that you wanted to solve (at least by looking at the
original patch) was to understand whether the vqmmc regulator changes
voltage level and then take different actions based on that in the
mmci host driver.

You don't need to change anything related to mmc_set_signal_voltage()
to accomplish that, do you? Moreover, I am worried that it may affect
the host driver's expectations from when
->start_signal_voltage_switch() may be called.

[...]

Kind regards
Uffe