ACK: [PATCH 1/2] ACPI / LPSS: Avoid PM quirks on suspend and resume from S3

[Colin Ian King]

On 01/08/18 09:17, Kai-Heng Feng wrote:
> From: "Rafael J. Wysocki" <rafael.j.wysocki at intel.com>
> 
> BugLink: https://bugs.launchpad.net/bugs/1774950
> 
> It is reported that commit a192aa923b66a (ACPI / LPSS: Consolidate
> runtime PM and system sleep handling) introduced a system suspend
> regression on some machines, but the only functional change made by
> it was to cause the PM quirks in the LPSS to also be used during
> system suspend and resume.  While that should always work for
> suspend-to-idle, it turns out to be problematic for S3
> (suspend-to-RAM).
> 
> To address that issue restore the previous S3 suspend and resume
> behavior of the LPSS to avoid applying PM quirks then.
> 
> Fixes: a192aa923b66a (ACPI / LPSS: Consolidate runtime PM and system sleep handling)
> Link: https://bugs.launchpad.net/bugs/1774950
> Reported-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
> Tested-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
> Reviewed-by: Ulf Hansson <ulf.hansson at linaro.org>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
> Acked-by: Mika Westerberg <mika.westerberg at linux.intel.com>
> Cc: 4.15+ <stable at vger.kernel.org> # 4.15+
> (cherry picked from commit a09c591306881dfb04387c6ee7b7e2e4683fa531)
> Signed-off-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
> ---
>  drivers/acpi/acpi_lpss.c | 18 +++++++++++-------
>  1 file changed, 11 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
> index c71f5a2a592e..35dd15fce2fa 100644
> --- a/drivers/acpi/acpi_lpss.c
> +++ b/drivers/acpi/acpi_lpss.c
> @@ -22,6 +22,7 @@
>  #include <linux/pm_domain.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/pwm.h>
> +#include <linux/suspend.h>
>  #include <linux/delay.h>
>  
>  #include "internal.h"
> @@ -803,9 +804,10 @@ static void lpss_iosf_exit_d3_state(void)
>  	mutex_unlock(&lpss_iosf_mutex);
>  }
>  
> -static int acpi_lpss_suspend(struct device *dev, bool wakeup)
> +static int acpi_lpss_suspend(struct device *dev, bool runtime)
>  {
>  	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
> +	bool wakeup = runtime || device_may_wakeup(dev);
>  	int ret;
>  
>  	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
> @@ -818,13 +820,14 @@ static int acpi_lpss_suspend(struct device *dev, bool wakeup)
>  	 * wrong status for devices being about to be powered off. See
>  	 * lpss_iosf_enter_d3_state() for further information.
>  	 */
> -	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
> +	if ((runtime || !pm_suspend_via_firmware()) &&
> +	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
>  		lpss_iosf_enter_d3_state();
>  
>  	return ret;
>  }
>  
> -static int acpi_lpss_resume(struct device *dev)
> +static int acpi_lpss_resume(struct device *dev, bool runtime)
>  {
>  	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
>  	int ret;
> @@ -833,7 +836,8 @@ static int acpi_lpss_resume(struct device *dev)
>  	 * This call is kept first to be in symmetry with
>  	 * acpi_lpss_runtime_suspend() one.
>  	 */
> -	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
> +	if ((runtime || !pm_resume_via_firmware()) &&
> +	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
>  		lpss_iosf_exit_d3_state();
>  
>  	ret = acpi_dev_resume(dev);
> @@ -857,12 +861,12 @@ static int acpi_lpss_suspend_late(struct device *dev)
>  		return 0;
>  
>  	ret = pm_generic_suspend_late(dev);
> -	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
> +	return ret ? ret : acpi_lpss_suspend(dev, false);
>  }
>  
>  static int acpi_lpss_resume_early(struct device *dev)
>  {
> -	int ret = acpi_lpss_resume(dev);
> +	int ret = acpi_lpss_resume(dev, false);
>  
>  	return ret ? ret : pm_generic_resume_early(dev);
>  }
> @@ -877,7 +881,7 @@ static int acpi_lpss_runtime_suspend(struct device *dev)
>  
>  static int acpi_lpss_runtime_resume(struct device *dev)
>  {
> -	int ret = acpi_lpss_resume(dev);
> +	int ret = acpi_lpss_resume(dev, true);
>  
>  	return ret ? ret : pm_generic_runtime_resume(dev);
>  }
> 

Positive test results, and clean upstream cherry pick,

Acked-by: Colin Ian King <colin.king at canonical.com>