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

From: Kai-Heng Feng
Date: Thu Jul 26 2018 - 04:15:15 EST




> On 2018Jul26, at 16:14, Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
>
> On Thu, Jul 26, 2018 at 5:46 AM, Kai-Heng Feng
> <kai.heng.feng@xxxxxxxxxxxxx> wrote:
>> 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!
>
> Good, thanks!
>
> I assume that S3 still works with this patch applied too.

Yes, S3 continues to work with this patch.

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);
>>> }