Re: [PATCH 2/2] firmware/psci: Switch to the sys-off handler API

From: Sudeep Holla <sudeep.holla@arm.com>
To: Samuel Holland <samuel@sholland.org>
Cc: Dmitry Osipenko <dmitry.osipenko@collabora.com>,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Sudeep Holla <sudeep.holla@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Lorenzo Pieralisi <lpieralisi@kernel.org>,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 2/2] firmware/psci: Switch to the sys-off handler API
Date: Mon, 7 Nov 2022 10:55:06 +0000	[thread overview]
Message-ID: <20221107105506.pfoxmngp7shhci3p@bogus> (raw)
In-Reply-To: <20221105214841.7828-3-samuel@sholland.org>

On Sat, Nov 05, 2022 at 04:48:40PM -0500, Samuel Holland wrote:
> Any other poweroff handlers registered at the default priority will
> run before the legacy pm_power_off() function. Register the PSCI
> poweroff handler with the correct priority to ensure it runs first.
> 
> Signed-off-by: Samuel Holland <samuel@sholland.org>
> ---
> 
>  drivers/firmware/psci/psci.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
> index e7bcfca4159f..6d528021925d 100644
> --- a/drivers/firmware/psci/psci.c
> +++ b/drivers/firmware/psci/psci.c
> @@ -13,7 +13,6 @@
>  #include <linux/errno.h>
>  #include <linux/linkage.h>
>  #include <linux/of.h>
> -#include <linux/pm.h>
>  #include <linux/printk.h>
>  #include <linux/psci.h>
>  #include <linux/reboot.h>
> @@ -322,9 +321,11 @@ static struct notifier_block psci_sys_reset_nb = {
>  	.priority = 129,
>  };
>  
> -static void psci_sys_poweroff(void)
> +static int psci_sys_poweroff(struct sys_off_data *data)
>  {
>  	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
> +
> +	return NOTIFY_DONE;

Just note that PSCI SYSTEM_OFF doesn't return and hence the above return
is useless. I understand the generic idea here and should be fine, just
thought of pointing that the firmware won't return from the call.

-- 
Regards,
Sudeep