[PATCH v2] i2c: designwear: Fix clk warning on suspend/resume

[PATCH v2] i2c: designwear: Fix clk warning on suspend/resume

[John Stultz]

On my HiKey board, I'm seeing clk warnings on suspend/resume,
which seem to be caused by runtime pm suspending the device,
then the same suspend hook being called again on suspend time.

This patch fixes this by setting the SYSTEM_SLEEP_PM_OPS to
using pm_runtime_force_suspend and  pm_runtime_force_resume.

Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-i2c@vger.kernel.org
Suggested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
v2: Switch to suggested fix by Jarkko.

 drivers/i2c/busses/i2c-designware-platdrv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 6ce4313..09f27ec 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -362,7 +362,7 @@ static int dw_i2c_plat_resume(struct device *dev)
 static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
 	.prepare = dw_i2c_plat_prepare,
 	.complete = dw_i2c_plat_complete,
-	SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
 	SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
 };
 
-- 
2.7.4

Re: [PATCH v2] i2c: designwear: Fix clk warning on suspend/resume

[Jarkko Nikula]

On 14.02.2017 06:05, John Stultz wrote:
> On my HiKey board, I'm seeing clk warnings on suspend/resume,
> which seem to be caused by runtime pm suspending the device,
> then the same suspend hook being called again on suspend time.
>
> This patch fixes this by setting the SYSTEM_SLEEP_PM_OPS to
> using pm_runtime_force_suspend and  pm_runtime_force_resume.
>
> Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
> Cc: Wolfram Sang <wsa@the-dreams.de>
> Cc: linux-i2c@vger.kernel.org
> Suggested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
> Signed-off-by: John Stultz <john.stultz@linaro.org>
> ---
> v2: Switch to suggested fix by Jarkko.
>
>  drivers/i2c/busses/i2c-designware-platdrv.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
> index 6ce4313..09f27ec 100644
> --- a/drivers/i2c/busses/i2c-designware-platdrv.c
> +++ b/drivers/i2c/busses/i2c-designware-platdrv.c
> @@ -362,7 +362,7 @@ static int dw_i2c_plat_resume(struct device *dev)
>  static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
>  	.prepare = dw_i2c_plat_prepare,
>  	.complete = dw_i2c_plat_complete,
> -	SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
> +	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
>  	SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
>  };

We need to hold this a bit. I've been debugging this on our platforms 
but haven't figured out yet how to fix a regression it is causing with 
drivers/acpi/acpi_lpss.c :-(

With this change in i2c-designware-platdrv.c the suspend path in 
acpi_lpss.c changes. First it saves its the register context in 
acpi_lpss_runtime_suspend() and powers down. Then the device which is 
now off will save again the register context (now reads full of 0xff...) 
in acpi_lpss_suspend_late() and restores wrong context (0xff...) when 
resuming.

-- 
Jarkko

Re: [PATCH v2] i2c: designwear: Fix clk warning on suspend/resume

[John Stultz]

On Tue, Feb 14, 2017 at 7:30 AM, Jarkko Nikula
<jarkko.nikula@linux.intel.com> wrote:
> On 14.02.2017 06:05, John Stultz wrote:
>>
>> On my HiKey board, I'm seeing clk warnings on suspend/resume,
>> which seem to be caused by runtime pm suspending the device,
>> then the same suspend hook being called again on suspend time.
>>
>> This patch fixes this by setting the SYSTEM_SLEEP_PM_OPS to
>> using pm_runtime_force_suspend and  pm_runtime_force_resume.
>>
>> Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
>> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
>> Cc: Wolfram Sang <wsa@the-dreams.de>
>> Cc: linux-i2c@vger.kernel.org
>> Suggested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
>> Signed-off-by: John Stultz <john.stultz@linaro.org>
>> ---
>> v2: Switch to suggested fix by Jarkko.
>>
>>  drivers/i2c/busses/i2c-designware-platdrv.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c
>> b/drivers/i2c/busses/i2c-designware-platdrv.c
>> index 6ce4313..09f27ec 100644
>> --- a/drivers/i2c/busses/i2c-designware-platdrv.c
>> +++ b/drivers/i2c/busses/i2c-designware-platdrv.c
>> @@ -362,7 +362,7 @@ static int dw_i2c_plat_resume(struct device *dev)
>>  static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
>>         .prepare = dw_i2c_plat_prepare,
>>         .complete = dw_i2c_plat_complete,
>> -       SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
>> +       SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
>> pm_runtime_force_resume)
>>         SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
>>  };
>
>
> We need to hold this a bit. I've been debugging this on our platforms but
> haven't figured out yet how to fix a regression it is causing with
> drivers/acpi/acpi_lpss.c :-(
>
> With this change in i2c-designware-platdrv.c the suspend path in acpi_lpss.c
> changes. First it saves its the register context in
> acpi_lpss_runtime_suspend() and powers down. Then the device which is now
> off will save again the register context (now reads full of 0xff...) in
> acpi_lpss_suspend_late() and restores wrong context (0xff...) when resuming.

Hey,
  Just wanted to follow up to see if any progress was made on this
issue? Anything you need from me?

thanks
-john