On Wed, 20 May 2020 at 16:30, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
>
> Hi Ulf,
>
> On Tue, May 19, 2020 at 5:24 PM Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
> > Before calling tmio_mmc_host_probe(), the caller is required to enable
> > clocks for its device, as to make it accessible when reading/writing
> > registers during probe.
> >
> > Therefore, the responsibility to disable these clocks, in the error path of
> > ->probe() and during ->remove(), is better managed outside
> > tmio_mmc_host_remove(). As a matter of fact, callers of
> > tmio_mmc_host_remove() already expects this to be the behaviour.
> >
> > However, there's a problem with tmio_mmc_host_remove() when the Kconfig
> > option, CONFIG_PM, is set. More precisely, tmio_mmc_host_remove() may then
> > disable the clock via runtime PM, which leads to clock enable/disable
> > imbalance problems, when the caller of tmio_mmc_host_remove() also tries to
> > disable the same clocks.
> >
> > To solve the problem, let's make sure tmio_mmc_host_remove() leaves the
> > device with clocks enabled, but also make sure to disable the IRQs, as we
> > normally do at ->runtime_suspend().
> >
> > Reported-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> > Reviewed-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> > Tested-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>
> Tested-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>
> (on R-Car Gen2, various Gen3, SH-Mobile AG5, R-Mobile A1, R-Mobile APE6,
> RZ/A1, and RZ/A2)
>
> Gr{oetje,eeting}s,
>
> Geert
Thanks, patch amended!
Kind regards
Uffe
