Re: [PATCH V3] i2c: busses: tegra: Add suspend-resume support

[Bitan Biswas]

On 6/6/19 11:27 PM, Dmitry Osipenko wrote:
> 07.06.2019 8:37, Bitan Biswas ÐÐÑÐÑ:
> > Post suspend I2C registers have power on reset values. Before any
> > transfer initialize I2C registers to prevent I2C transfer timeout
> > and implement suspend and resume callbacks needed. Fix below errors
> > post suspend:
> >
> > 1) Tegra I2C transfer timeout during jetson tx2 resume:
> >
> > [   27.520613] pca953x 1-0074: calling pca953x_resume+0x0/0x1b0 @ 2939, parent: i2c-1
> > [   27.633623] tegra-i2c 3160000.i2c: i2c transfer timed out
> > [   27.639162] pca953x 1-0074: Unable to sync registers 0x3-0x5. -110
> > [   27.645336] pca953x 1-0074: Failed to sync GPIO dir registers: -110
> > [   27.651596] PM: dpm_run_callback(): pca953x_resume+0x0/0x1b0 returns -110
> > [   27.658375] pca953x 1-0074: pca953x_resume+0x0/0x1b0 returned -110 after 127152 usecs
> > [   27.666194] PM: Device 1-0074 failed to resume: error -110
> >
> > 2) Tegra I2C transfer timeout error on jetson Xavier post resume.
> >
> > Remove i2c bus lock-unlock calls in resume callback as i2c_mark_adapter_*
> > (suspended-resumed) help ensure i2c core calls from client are not
> > executed before i2c-tegra resume.
> >
> > Signed-off-by: Bitan Biswas <bbiswas@xxxxxxxxxx>
> > ---
> >   drivers/i2c/busses/i2c-tegra.c | 24 ++++++++++++++++++++++++
> >   1 file changed, 24 insertions(+)
> >
> > diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
> > index ebaa78d..1dbba39 100644
> > --- a/drivers/i2c/busses/i2c-tegra.c
> > +++ b/drivers/i2c/busses/i2c-tegra.c
> > @@ -1687,7 +1687,31 @@ static int tegra_i2c_remove(struct platform_device *pdev)
> >   }
> >   
> >   #ifdef CONFIG_PM_SLEEP
> > +static int tegra_i2c_suspend(struct device *dev)
> > +{
> > +	struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
> > +
> > +	i2c_mark_adapter_suspended(&i2c_dev->adapter);
> > +
> > +	return 0;
> > +}
> > +
> > +static int tegra_i2c_resume(struct device *dev)
> > +{
> > +	struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
> > +	int err;
> > +
> > +	err = tegra_i2c_init(i2c_dev, false);
> > +	if (err)
> > +		return err;
> > +
> > +	i2c_mark_adapter_resumed(&i2c_dev->adapter);
> > +
> > +	return 0;
> > +}
> > +
> >   static const struct dev_pm_ops tegra_i2c_pm = {
> > +	SET_SYSTEM_SLEEP_PM_OPS(tegra_i2c_suspend, tegra_i2c_resume)
> >   	SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend, tegra_i2c_runtime_resume,
> >   			   NULL)
> >   };
>
> Thanks!
>
> Reviewed-by: Dmitry Osipenko <digetx@xxxxxxxxx>

Please get back if there is/are any further review comment(s) for below 
patch.


http://patchwork.ozlabs.org/patch/1111570/

-Thanks,
 Bitan