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SubjectRe: [PATCH] devfreq: Suspend all devices on system shutdown
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Hi,

On 19. 1. 25. 오후 10:54, Marek Szyprowski wrote:
> This way devfreq core ensures that all its devices will be set to safe
> operation points before reboot operation. There are board on which some
> aggressive power saving operation points are behind the capabilities of
> the bootloader to properly reset the hardware and boot the board. This
> way one can avoid board crash early after reboot.
>
> Similar pattern is used in CPUfreq subsystem.
>
> Reported-by: Markus Reichl <m.reichl@fivetechno.de>
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
> drivers/devfreq/devfreq.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 0ae3de76833b..f6aba8344c56 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -23,6 +23,7 @@
> #include <linux/devfreq.h>
> #include <linux/workqueue.h>
> #include <linux/platform_device.h>
> +#include <linux/syscore_ops.h>
> #include <linux/list.h>
> #include <linux/printk.h>
> #include <linux/hrtimer.h>
> @@ -1422,6 +1423,10 @@ static struct attribute *devfreq_attrs[] = {
> };
> ATTRIBUTE_GROUPS(devfreq);
>
> +static struct syscore_ops devfreq_syscore_ops = {
> + .shutdown = devfreq_suspend,
> +};
> +
> static int __init devfreq_init(void)
> {
> devfreq_class = class_create(THIS_MODULE, "devfreq");
> @@ -1438,6 +1443,8 @@ static int __init devfreq_init(void)
> }
> devfreq_class->dev_groups = devfreq_groups;
>
> + register_syscore_ops(&devfreq_syscore_ops);
> +
> return 0;
> }
> subsys_initcall(devfreq_init);
>

Looks good to me.
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>

--
Best Regards,
Chanwoo Choi
Samsung Electronics

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