Re: [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM

From: Adrian Hunter
Date: Mon Dec 04 2017 - 06:52:05 EST


On 01/12/17 15:58, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Prevent rpm_get_suppliers() from returning an error code if runtime
> PM is disabled for one or more of the supplier devices it wants to
> runtime-resume, so as to make runtime PM work for devices with links
> to suppliers that don't use runtime PM (such links may be created
> during device enumeration even before it is known whether or not
> runtime PM will be enabled for the devices in question, for example).
>
> Reported-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> Fixes: 21d5c57b3726 (PM / runtime: Use device links)
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Tested-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>

> ---
> drivers/base/power/runtime.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> Index: linux-pm/drivers/base/power/runtime.c
> ===================================================================
> --- linux-pm.orig/drivers/base/power/runtime.c
> +++ linux-pm/drivers/base/power/runtime.c
> @@ -276,7 +276,8 @@ static int rpm_get_suppliers(struct devi
> continue;
>
> retval = pm_runtime_get_sync(link->supplier);
> - if (retval < 0) {
> + /* Ignore suppliers with disabled runtime PM. */
> + if (retval < 0 && retval != -EACCES) {
> pm_runtime_put_noidle(link->supplier);
> return retval;
> }
>
>