Re: [PATCH/RFC v2 2/2] mmc: core: Call mmc_power_off_nofity() if pm_suspend_via_firmware()

Re: [PATCH/RFC v2 2/2] mmc: core: Call mmc_power_off_nofity() if pm_suspend_via_firmware()

[Sergei Shtylyov]

Hello!

On 19.06.2020 14:29, Yoshihiro Shimoda wrote:

> If pm_suspend_via_firmware() returns true, the system will be able
> to cut both vcc and vccq in the suspend. So, call
> mmc_power_off_nofity() if pm_suspend_via_firmware() returns true.

    mmc_poweroff_notify()? :-)

> Note that we should not update the MMC_CAP2_FULL_PWR_CYCLE caps
> because the mmc_select_voltage() checks the caps when attaches
> a mmc/sd.
> 
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> ---
>   drivers/mmc/core/mmc.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index 4203303..81941fd 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
[...]
> @@ -2038,7 +2039,8 @@ static int _mmc_suspend(struct mmc_host *host, bool is_suspend)
>   		goto out;
>   
>   	if (mmc_can_poweroff_notify(host->card) &&
> -		((host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) || !is_suspend))
> +	    ((host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) || !is_suspend ||
> +	     pm_suspend_via_firmware()))
>   		err = mmc_poweroff_notify(host->card, notify_type);
>   	else if (mmc_can_sleep(host->card))
>   		err = mmc_sleep(host);
> 

MBR, Sergei

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH/RFC v2 0/2] treewide: fix _mmc_suspend() on PSCI

[Geert Uytterhoeven]

Hi Shimoda-san,

On Fri, Jun 19, 2020 at 2:42 PM Yoshihiro Shimoda
<yoshihiro.shimoda.uh@renesas.com> wrote:
> We can detect whether the system is going to suspend by using
> pm_suspend_via_firmware() API. So, this patch series update
> both PSCI and MMC driver for my environment (r8a77951-salvator-xs).

Cool, didn't know about pm_set_.*_via_firmware().

Looks like this can be used in the clock and pin control drivers, too.
Currently they're checking for !psci_ops.cpu_suspend.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH/RFC v2 1/2] firmware: psci: call pm_set_suspend_via_firmware()

[Sudeep Holla]

(This patch never made it to my inbox, may be due to ALKML issues on that day)

On Fri, Jun 19, 2020 at 08:29:02PM +0900, Yoshihiro Shimoda wrote:
> Call pm_set_suspend_via_firmware() in .begin() of psci_suspend_ops
> to use pm_suspend_via_firmware() on PSCI environment.
>

I don't have issues with this change as such, but I need to understand
how and why this is used. I will comment on that separately.

--
Regards,
Sudeep

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

RE: [PATCH/RFC v2 1/2] firmware: psci: call pm_set_suspend_via_firmware()

[Yoshihiro Shimoda]

Hi Sudeep,

> From: Sudeep Holla, Sent: Monday, June 29, 2020 11:33 PM
> 
> (This patch never made it to my inbox, may be due to ALKML issues on that day)
> 
> On Fri, Jun 19, 2020 at 08:29:02PM +0900, Yoshihiro Shimoda wrote:
> > Call pm_set_suspend_via_firmware() in .begin() of psci_suspend_ops
> > to use pm_suspend_via_firmware() on PSCI environment.
> >
> 
> I don't have issues with this change as such, but I need to understand
> how and why this is used. I will comment on that separately.

I thought MMC driver could use this API to detect whether the firmware was suspending or not.
However, Ulf said this was not a good way because all implementation of PSCI
will not turn the power off while system suspend [1]. Also, as you and Mark said on other
email thread [2], the current PSCI specification cannot inform system suspend state
to OS (Linux).

So, I think I should recall this patch because this cannot get expected information.


[1]
https://lore.kernel.org/linux-renesas-soc/CAPDyKFq-dEPaU094hrk2xg18VpJAsbnf8enieFmcMhKiB1bW1A@mail.gmail.com/


https://lore.kernel.org/linux-renesas-soc/CAMuHMdXh1Hh6H35Mp8hBJBykUucRNwxTmW+U9SHM+xhrcwasDA@mail.gmail.com/T/#m442a2ce972cfdb3ff33637c120c8d096e4d07af8

Best regards,
Yoshihiro Shimoda

> --
> Regards,
> Sudeep

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel