[RFC v3 04/13] ahci-platform: Undo pdata->resume on resume failure

[Tejun Heo]

Hello,

On Sun, Jan 19, 2014 at 12:48:46AM +0100, Hans de Goede wrote:
> When the ahci_resume fails the error handling code tries to undo all changes
> made, but it was not undoing the results of pdata->resume.
> 
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
> ---
>  drivers/ata/ahci_platform.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
> index dc1ef73..41720cb 100644
> --- a/drivers/ata/ahci_platform.c
> +++ b/drivers/ata/ahci_platform.c
> @@ -307,7 +307,7 @@ static int ahci_resume(struct device *dev)
>  	if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
>  		rc = ahci_reset_controller(host);
>  		if (rc)
> -			goto disable_unprepare_clk;
> +			goto pdata_suspend;
>  
>  		ahci_init_controller(host);
>  	}
> @@ -316,6 +316,9 @@ static int ahci_resume(struct device *dev)
>  
>  	return 0;
>  
> +pdata_suspend:
> +	if (pdata && pdata->suspend)
> +		pdata->suspend(dev);
>  disable_unprepare_clk:
>  	if (!IS_ERR(hpriv->clk))
>  		clk_disable_unprepare(hpriv->clk);

Hmmmm... resume isn't an operation you can revert without side-effect
when the whole system is waking up from sleep.  e.g. think about what
should happen the driver is removed and loaded again - it should be
able to reinitialized the device, which is unlikely to work if the
device is suspended at the platform level.  If resume fails, the right
state to be in is "failed with as much as resumed" instead of
"suspended".

Thanks.

-- 
tejun