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

[Kai-Heng Feng]

Hi Rafael,

> On 2018Jul24, at 18:36, Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote:
> 
> On Tuesday, July 24, 2018 11:13:42 AM CEST Rafael J. Wysocki wrote:
>> On Tuesday, July 24, 2018 10:46:09 AM CEST Kai Heng Feng wrote:
>>> Hi Rafael,
>>> 
>>>> On Jun 13, 2018, at 7:17 PM, Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote:
>>>> 
>>>> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>>>> 
>>>> 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.
>>> 
>>> The users reported that this patch does fix the S3 issue, but the S4 still  
>>> fails.
>>> 
>>> Please refer to [1] for more for user's testing result.
>>> 
>>> [1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1774950/comments/60
>> 
>> Please ask the users to test the patch below, then, on top of the $subject one.
> 
> There was a mistake in the previous patch I posted, sorry about that.
> 
> Please test this one instead:

The result is positive, thanks!

Kai-Heng

> 
> ---
> drivers/acpi/acpi_lpss.c |   26 +++++++++++++++++---------
> 1 file changed, 17 insertions(+), 9 deletions(-)
> 
> Index: linux-pm/drivers/acpi/acpi_lpss.c
> ===================================================================
> --- linux-pm.orig/drivers/acpi/acpi_lpss.c
> +++ linux-pm/drivers/acpi/acpi_lpss.c
> @@ -879,6 +879,7 @@ static void acpi_lpss_dismiss(struct dev
> #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
> 
> static DEFINE_MUTEX(lpss_iosf_mutex);
> +static bool lpss_iosf_d3_entered;
> 
> static void lpss_iosf_enter_d3_state(void)
> {
> @@ -921,6 +922,9 @@ static void lpss_iosf_enter_d3_state(voi
> 
> 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
> 			LPSS_IOSF_GPIODEF0, value1, mask1);
> +
> +	lpss_iosf_d3_entered = true;
> +
> exit:
> 	mutex_unlock(&lpss_iosf_mutex);
> }
> @@ -935,6 +939,11 @@ static void lpss_iosf_exit_d3_state(void
> 
> 	mutex_lock(&lpss_iosf_mutex);
> 
> +	if (!lpss_iosf_d3_entered)
> +		goto exit;
> +
> +	lpss_iosf_d3_entered = false;
> +
> 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
> 			LPSS_IOSF_GPIODEF0, value1, mask1);
> 
> @@ -944,13 +953,13 @@ static void lpss_iosf_exit_d3_state(void
> 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
> 			LPSS_IOSF_PMCSR, value2, mask2);
> 
> +exit:
> 	mutex_unlock(&lpss_iosf_mutex);
> }
> 
> -static int acpi_lpss_suspend(struct device *dev, bool runtime)
> +static int acpi_lpss_suspend(struct device *dev, bool wakeup)
> {
> 	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)
> @@ -963,14 +972,14 @@ static int acpi_lpss_suspend(struct devi
> 	 * wrong status for devices being about to be powered off. See
> 	 * lpss_iosf_enter_d3_state() for further information.
> 	 */
> -	if ((runtime || !pm_suspend_via_firmware()) &&
> +	if (acpi_target_system_state() == ACPI_STATE_S0 &&
> 	    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, bool runtime)
> +static int acpi_lpss_resume(struct device *dev)
> {
> 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
> 	int ret;
> @@ -979,8 +988,7 @@ static int acpi_lpss_resume(struct devic
> 	 * This call is kept first to be in symmetry with
> 	 * acpi_lpss_runtime_suspend() one.
> 	 */
> -	if ((runtime || !pm_resume_via_firmware()) &&
> -	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
> +	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
> 		lpss_iosf_exit_d3_state();
> 
> 	ret = acpi_dev_resume(dev);
> @@ -1004,12 +1012,12 @@ static int acpi_lpss_suspend_late(struct
> 		return 0;
> 
> 	ret = pm_generic_suspend_late(dev);
> -	return ret ? ret : acpi_lpss_suspend(dev, false);
> +	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
> }
> 
> static int acpi_lpss_resume_early(struct device *dev)
> {
> -	int ret = acpi_lpss_resume(dev, false);
> +	int ret = acpi_lpss_resume(dev);
> 
> 	return ret ? ret : pm_generic_resume_early(dev);
> }
> @@ -1024,7 +1032,7 @@ static int acpi_lpss_runtime_suspend(str
> 
> static int acpi_lpss_runtime_resume(struct device *dev)
> {
> -	int ret = acpi_lpss_resume(dev, true);
> +	int ret = acpi_lpss_resume(dev);
> 
> 	return ret ? ret : pm_generic_runtime_resume(dev);
> }