Subject: Re: [PATCH] rtc/rtc-opal: Disable rtc-alarms when opal doesn't support tpo

From: Neelesh Gupta <[email-masked]>
Date: Wed, 03 Jun 2015 11:04:11 +0530

On 06/03/2015 10:21 AM, Vaibhav Jain wrote:
> rtc-opal driver provides support for rtc alarms via
> times-power-on(tpo). However some platforms like BML use a fake rtc
> clock and don't support tpo. Such platforms are indicated by the missing
> 'has-tpo' property in the device tree.
>
> Current implementation however enables callback for
> rtc_class_ops.read/set alarm irrespective of the tpo support from the
> platform. This results in a failed opal call when kernel tries to read
> an existing alarms via opal_get_tpo_time during rtc device registration.
>
> This patch fixes this issue by setting opal_rtc_ops.read/set_alarm
> callback pointers only when tpo is supported.
>
> Signed-off-by: Vaibhav Jain <[email-masked]>

Acked-by: Neelesh Gupta <[email-masked]>

Thanks,
Neelesh.

> ---
>   drivers/rtc/rtc-opal.c | 9 +++++----
>   1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/rtc/rtc-opal.c b/drivers/rtc/rtc-opal.c
> index 7061dca..1125641 100644
> --- a/drivers/rtc/rtc-opal.c
> +++ b/drivers/rtc/rtc-opal.c
> @@ -190,11 +190,9 @@ exit:
>   	return rc;
>   }
>
> -static const struct rtc_class_ops opal_rtc_ops = {
> +static struct rtc_class_ops opal_rtc_ops = {
>   	.read_time	= opal_get_rtc_time,
>   	.set_time	= opal_set_rtc_time,
> -	.read_alarm	= opal_get_tpo_time,
> -	.set_alarm	= opal_set_tpo_time,
>   };
>
>   static int opal_rtc_probe(struct platform_device *pdev)
> @@ -202,8 +200,11 @@ static int opal_rtc_probe(struct platform_device *pdev)
>   	struct rtc_device *rtc;
>
>   	if (pdev->dev.of_node && of_get_property(pdev->dev.of_node, "has-tpo",
> -						 NULL))
> +						 NULL)) {
>   		device_set_wakeup_capable(&pdev->dev, true);
> +		opal_rtc_ops.read_alarm	= opal_get_tpo_time;
> +		opal_rtc_ops.set_alarm = opal_set_tpo_time;
> +	}
>
>   	rtc = devm_rtc_device_register(&pdev->dev, DRVNAME, &opal_rtc_ops,
>   				       THIS_MODULE);