[PATCH 02/11] i2c: imx-lpi2c: add runtime pm support

Clark Wang xiaoning.wang at nxp.com
Fri Mar 19 05:33:15 GMT 2021


> -----Original Message-----
> From: Aisheng Dong <aisheng.dong at nxp.com>
> Sent: Friday, March 19, 2021 12:40
> To: Clark Wang <xiaoning.wang at nxp.com>; shawnguo at kernel.org;
> s.hauer at pengutronix.de
> Cc: kernel at pengutronix.de; festevam at gmail.com; dl-linux-imx <linux-
> imx at nxp.com>; sumit.semwal at linaro.org; christian.koenig at amd.com;
> linux-i2c at vger.kernel.org; linux-arm-kernel at lists.infradead.org; linux-
> kernel at vger.kernel.org
> Subject: RE: [PATCH 02/11] i2c: imx-lpi2c: add runtime pm support
> 
> > From: Clark Wang <xiaoning.wang at nxp.com>
> > Sent: Wednesday, March 17, 2021 2:54 PM
> > Subject: [PATCH 02/11] i2c: imx-lpi2c: add runtime pm support
> >
> > - Add runtime pm support to dynamicly manage the clock.
> > - Put the suspend to suspend_noirq.
> > - Call .pm_runtime_force_suspend() to force runtime pm suspended
> >   in .suspend_noirq().
> >
> 
> The patch title needs to be improved as the driver already supports rpm.
> And do one thing in one patch.

Thanks. I will split this patch into several and resend.

Best Regards,
Clark Wang
> 
> > Signed-off-by: Fugang Duan <fugang.duan at nxp.com>
> > Signed-off-by: Gao Pan <pandy.gao at nxp.com>
> > Reviewed-by: Anson Huang <Anson.Huang at nxp.com>
> 
> Please add your sign-off.
> 
> > ---
> >  drivers/i2c/busses/i2c-imx-lpi2c.c | 50
> > ++++++++++++++++++++----------
> >  1 file changed, 33 insertions(+), 17 deletions(-)
> >
> > diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c
> > b/drivers/i2c/busses/i2c-imx-lpi2c.c
> > index bbf44ac95021..1e920e7ac7c1 100644
> > --- a/drivers/i2c/busses/i2c-imx-lpi2c.c
> > +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
> > @@ -574,7 +574,8 @@ static int lpi2c_imx_probe(struct platform_device
> > *pdev)
> >  	if (ret)
> >  		lpi2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ;
> >
> > -	ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr, 0,
> > +	ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr,
> > +			       IRQF_NO_SUSPEND,
> 
> This belongs to a separate patch
> 
> >  			       pdev->name, lpi2c_imx);
> >  	if (ret) {
> >  		dev_err(&pdev->dev, "can't claim irq %d\n", irq); @@ -
> 584,35
> > +585,32 @@ static int lpi2c_imx_probe(struct platform_device *pdev)
> >  	i2c_set_adapdata(&lpi2c_imx->adapter, lpi2c_imx);
> >  	platform_set_drvdata(pdev, lpi2c_imx);
> >
> > -	ret = clk_prepare_enable(lpi2c_imx->clk);
> > -	if (ret) {
> > -		dev_err(&pdev->dev, "clk enable failed %d\n", ret);
> > -		return ret;
> > -	}
> > -
> >  	pm_runtime_set_autosuspend_delay(&pdev->dev,
> I2C_PM_TIMEOUT);
> >  	pm_runtime_use_autosuspend(&pdev->dev);
> > -	pm_runtime_get_noresume(&pdev->dev);
> > -	pm_runtime_set_active(&pdev->dev);
> >  	pm_runtime_enable(&pdev->dev);
> >
> > +	ret = pm_runtime_get_sync(&pdev->dev);
> > +	if (ret < 0) {
> > +		pm_runtime_put_noidle(&pdev->dev);
> > +		dev_err(&pdev->dev, "failed to enable clock\n");
> > +		return ret;
> > +	}
> 
> Can't current clk control via rpm work well?
> Please describe why need change.
> 
> > +
> >  	temp = readl(lpi2c_imx->base + LPI2C_PARAM);
> >  	lpi2c_imx->txfifosize = 1 << (temp & 0x0f);
> >  	lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f);
> >
> > +	pm_runtime_put(&pdev->dev);
> > +
> >  	ret = i2c_add_adapter(&lpi2c_imx->adapter);
> >  	if (ret)
> >  		goto rpm_disable;
> >
> > -	pm_runtime_mark_last_busy(&pdev->dev);
> > -	pm_runtime_put_autosuspend(&pdev->dev);
> > -
> >  	dev_info(&lpi2c_imx->adapter.dev, "LPI2C adapter registered\n");
> >
> >  	return 0;
> >
> >  rpm_disable:
> > -	pm_runtime_put(&pdev->dev);
> >  	pm_runtime_disable(&pdev->dev);
> >  	pm_runtime_dont_use_autosuspend(&pdev->dev);
> >
> > @@ -636,7 +634,7 @@ static int __maybe_unused
> > lpi2c_runtime_suspend(struct device *dev)
> >  	struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
> >
> >  	clk_disable_unprepare(lpi2c_imx->clk);
> > -	pinctrl_pm_select_sleep_state(dev);
> > +	pinctrl_pm_select_idle_state(dev);
> 
> This belongs to a separate patch
> 
> >
> >  	return 0;
> >  }
> > @@ -649,16 +647,34 @@ static int __maybe_unused
> > lpi2c_runtime_resume(struct device *dev)
> >  	pinctrl_pm_select_default_state(dev);
> >  	ret = clk_prepare_enable(lpi2c_imx->clk);
> >  	if (ret) {
> > -		dev_err(dev, "failed to enable I2C clock, ret=%d\n", ret);
> > +		dev_err(dev, "can't enable I2C clock, ret=%d\n", ret);
> 
> Probably unnecessary change
> 
> >  		return ret;
> >  	}
> >
> > +	return ret;
> > +}
> > +
> > +static int lpi2c_suspend_noirq(struct device *dev) {
> > +	int ret;
> > +
> > +	ret = pm_runtime_force_suspend(dev);
> > +	if (ret)
> > +		return ret;
> > +
> > +	pinctrl_pm_select_sleep_state(dev);
> > +
> >  	return 0;
> >  }
> >
> > +static int lpi2c_resume_noirq(struct device *dev) {
> > +	return pm_runtime_force_resume(dev); }
> > +
> >  static const struct dev_pm_ops lpi2c_pm_ops = {
> > -	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> > -				      pm_runtime_force_resume)
> > +	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(lpi2c_suspend_noirq,
> > +				     lpi2c_resume_noirq)
> 
> Belongs to separate change and explain why need do this
> 
> >  	SET_RUNTIME_PM_OPS(lpi2c_runtime_suspend,
> >  			   lpi2c_runtime_resume, NULL)
> >  };
> > --
> > 2.25.1

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