Re: [PATCH v8 2/4] block: add runtime pm helpers

[Alan Stern <stern@rowland.harvard.edu>]

On Wed, 30 Jan 2013, Aaron Lu wrote:

> From: Lin Ming <ming.m.lin@intel.com>
> 
> Add runtime pm helper functions:
> 
> void blk_pm_runtime_init(struct request_queue *q, struct device *dev)
>   - Initialization function for drivers to call.
> 
> int blk_pre_runtime_suspend(struct request_queue *q)
>   - If any requests are in the queue, mark last busy and return -EBUSY.
>     Otherwise set q->rpm_status to RPM_SUSPENDING and return 0.
> 
> void blk_post_runtime_suspend(struct request_queue *q, int err)
>   - If the suspend succeeded then set q->rpm_status to RPM_SUSPENDED.
>     Otherwise set it to RPM_ACTIVE.
> 
> void blk_pre_runtime_resume(struct request_queue *q)
>   - Set q->rpm_status to RPM_RESUMING.
> 
> void blk_post_runtime_resume(struct request_queue *q, int err)
>   - If the resume succeeded then set q->rpm_status to RPM_ACTIVE
>     and call __blk_run_queue, then mark last busy and autosuspend.
>     Otherwise set q->rpm_status to RPM_SUSPENDED.
> 
> Signed-off-by: Lin Ming <ming.m.lin@intel.com>
> Signed-off-by: Aaron Lu <aaron.lu@intel.com>

> +void blk_pm_runtime_init(struct request_queue *q, struct device *dev)
> +{
> +	q->dev = dev;
> +	q->rpm_status = RPM_ACTIVE;
> +	pm_runtime_set_autosuspend_delay(q->dev, -1);
> +	pm_runtime_use_autosuspend(q->dev);
> +	pm_runtime_mark_last_busy(q->dev);
> +	pm_runtime_autosuspend(q->dev);

This last line is no longer needed.  It can't do anything useful, since 
autosuspends are disabled (the delay is -1).

Alan Stern