[PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue

[PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue

[Han Xu]

fix several issues when system suspend/resume,

- leverage the runtime pm for system suspend/resume
- enable the clock before register access
- re-apply timing settings
- set the proper pinctrl state

Signed-off-by: Han Xu <han.xu@nxp.com>
---
 drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 59 ++++++++++++++++------
 1 file changed, 44 insertions(+), 15 deletions(-)

diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
index 334fe3130285..37437d47ab9a 100644
--- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
@@ -15,6 +15,7 @@
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/dma/mxs-dma.h>
 #include "gpmi-nand.h"
 #include "gpmi-regs.h"
@@ -146,7 +147,11 @@ static int __gpmi_enable_clk(struct gpmi_nand_data *this, bool v)
 static int gpmi_init(struct gpmi_nand_data *this)
 {
 	struct resources *r = &this->resources;
-	int ret;
+	int ret = 0;
+
+	ret = pm_runtime_get_sync(this->dev);
+	if (ret < 0)
+		return ret;
 
 	ret = gpmi_reset_block(r->gpmi_regs, false);
 	if (ret)
@@ -179,8 +184,10 @@ static int gpmi_init(struct gpmi_nand_data *this)
 	 */
 	writel(BM_GPMI_CTRL1_DECOUPLE_CS, r->gpmi_regs + HW_GPMI_CTRL1_SET);
 
-	return 0;
 err_out:
+	pm_runtime_mark_last_busy(this->dev);
+	pm_runtime_put_autosuspend(this->dev);
+
 	return ret;
 }
 
@@ -528,7 +535,7 @@ static int common_nfc_set_geometry(struct gpmi_nand_data *this)
 static int bch_set_geometry(struct gpmi_nand_data *this)
 {
 	struct resources *r = &this->resources;
-	int ret;
+	int ret = 0;
 
 	ret = common_nfc_set_geometry(this);
 	if (ret)
@@ -550,7 +557,6 @@ static int bch_set_geometry(struct gpmi_nand_data *this)
 	/* Set *all* chip selects to use layout 0. */
 	writel(0, r->bch_regs + HW_BCH_LAYOUTSELECT);
 
-	ret = 0;
 err_out:
 	pm_runtime_mark_last_busy(this->dev);
 	pm_runtime_put_autosuspend(this->dev);
@@ -2676,7 +2682,7 @@ static int gpmi_nand_probe(struct platform_device *pdev)
 	return 0;
 
 exit_nfc_init:
-	pm_runtime_put(&pdev->dev);
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	release_resources(this);
 exit_acquire_resources:
@@ -2688,7 +2694,6 @@ static int gpmi_nand_remove(struct platform_device *pdev)
 {
 	struct gpmi_nand_data *this = platform_get_drvdata(pdev);
 
-	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
 	nand_release(&this->nand);
@@ -2700,10 +2705,12 @@ static int gpmi_nand_remove(struct platform_device *pdev)
 #ifdef CONFIG_PM_SLEEP
 static int gpmi_pm_suspend(struct device *dev)
 {
-	struct gpmi_nand_data *this = dev_get_drvdata(dev);
+	int ret;
 
-	release_dma_channels(this);
-	return 0;
+	pinctrl_pm_select_sleep_state(dev);
+	ret = pm_runtime_force_suspend(dev);
+
+	return ret;
 }
 
 static int gpmi_pm_resume(struct device *dev)
@@ -2711,9 +2718,13 @@ static int gpmi_pm_resume(struct device *dev)
 	struct gpmi_nand_data *this = dev_get_drvdata(dev);
 	int ret;
 
-	ret = acquire_dma_channels(this);
-	if (ret < 0)
+	ret = pm_runtime_force_resume(dev);
+	if (ret) {
+		dev_err(this->dev, "Error in resume %d\n", ret);
 		return ret;
+	}
+
+	pinctrl_pm_select_default_state(dev);
 
 	/* re-init the GPMI registers */
 	ret = gpmi_init(this);
@@ -2729,22 +2740,40 @@ static int gpmi_pm_resume(struct device *dev)
 		return ret;
 	}
 
+	/* re-apply the timing setting */
+	this->hw.must_apply_timings = true;
+
 	return 0;
 }
 #endif /* CONFIG_PM_SLEEP */
 
-static int __maybe_unused gpmi_runtime_suspend(struct device *dev)
+#define gpmi_enable_clk(x)	__gpmi_enable_clk(x, true)
+#define gpmi_disable_clk(x)	__gpmi_enable_clk(x, false)
+
+static int gpmi_runtime_suspend(struct device *dev)
 {
 	struct gpmi_nand_data *this = dev_get_drvdata(dev);
 
-	return __gpmi_enable_clk(this, false);
+	gpmi_disable_clk(this);
+	release_dma_channels(this);
+
+	return 0;
 }
 
-static int __maybe_unused gpmi_runtime_resume(struct device *dev)
+static int gpmi_runtime_resume(struct device *dev)
 {
 	struct gpmi_nand_data *this = dev_get_drvdata(dev);
+	int ret;
 
-	return __gpmi_enable_clk(this, true);
+	ret = gpmi_enable_clk(this);
+	if (ret)
+		return ret;
+
+	ret = acquire_dma_channels(this);
+	if (ret < 0)
+		return ret;
+
+	return 0;
 }
 
 static const struct dev_pm_ops gpmi_pm_ops = {
-- 
2.17.1


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Re: [PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue

[Miquel Raynal]

Hi Esben, Han,

Han Xu <han.xu@nxp.com> wrote on Fri, 10 Jan 2020 01:05:56 +0800:

> fix several issues when system suspend/resume,
> 
> - leverage the runtime pm for system suspend/resume
> - enable the clock before register access
> - re-apply timing settings
> - set the proper pinctrl state

Esben are you fine with this patch?

Or maybe Han you could take over Eben's patch and extend it?

> 
> Signed-off-by: Han Xu <han.xu@nxp.com>
> ---
>  drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 59 ++++++++++++++++------
>  1 file changed, 44 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> index 334fe3130285..37437d47ab9a 100644
> --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> @@ -15,6 +15,7 @@
>  #include <linux/of.h>
>  #include <linux/of_device.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/pinctrl/consumer.h>
>  #include <linux/dma/mxs-dma.h>
>  #include "gpmi-nand.h"
>  #include "gpmi-regs.h"
> @@ -146,7 +147,11 @@ static int __gpmi_enable_clk(struct gpmi_nand_data *this, bool v)
>  static int gpmi_init(struct gpmi_nand_data *this)
>  {
>  	struct resources *r = &this->resources;
> -	int ret;
> +	int ret = 0;
> +
> +	ret = pm_runtime_get_sync(this->dev);
> +	if (ret < 0)
> +		return ret;
>  
>  	ret = gpmi_reset_block(r->gpmi_regs, false);
>  	if (ret)
> @@ -179,8 +184,10 @@ static int gpmi_init(struct gpmi_nand_data *this)
>  	 */
>  	writel(BM_GPMI_CTRL1_DECOUPLE_CS, r->gpmi_regs + HW_GPMI_CTRL1_SET);
>  
> -	return 0;
>  err_out:
> +	pm_runtime_mark_last_busy(this->dev);
> +	pm_runtime_put_autosuspend(this->dev);
> +
>  	return ret;
>  }
>  
> @@ -528,7 +535,7 @@ static int common_nfc_set_geometry(struct gpmi_nand_data *this)
>  static int bch_set_geometry(struct gpmi_nand_data *this)
>  {
>  	struct resources *r = &this->resources;
> -	int ret;
> +	int ret = 0;
>  
>  	ret = common_nfc_set_geometry(this);
>  	if (ret)
> @@ -550,7 +557,6 @@ static int bch_set_geometry(struct gpmi_nand_data *this)
>  	/* Set *all* chip selects to use layout 0. */
>  	writel(0, r->bch_regs + HW_BCH_LAYOUTSELECT);
>  
> -	ret = 0;
>  err_out:
>  	pm_runtime_mark_last_busy(this->dev);
>  	pm_runtime_put_autosuspend(this->dev);
> @@ -2676,7 +2682,7 @@ static int gpmi_nand_probe(struct platform_device *pdev)
>  	return 0;
>  
>  exit_nfc_init:
> -	pm_runtime_put(&pdev->dev);
> +	pm_runtime_dont_use_autosuspend(&pdev->dev);
>  	pm_runtime_disable(&pdev->dev);
>  	release_resources(this);
>  exit_acquire_resources:
> @@ -2688,7 +2694,6 @@ static int gpmi_nand_remove(struct platform_device *pdev)
>  {
>  	struct gpmi_nand_data *this = platform_get_drvdata(pdev);
>  
> -	pm_runtime_put_sync(&pdev->dev);
>  	pm_runtime_disable(&pdev->dev);
>  
>  	nand_release(&this->nand);
> @@ -2700,10 +2705,12 @@ static int gpmi_nand_remove(struct platform_device *pdev)
>  #ifdef CONFIG_PM_SLEEP
>  static int gpmi_pm_suspend(struct device *dev)
>  {
> -	struct gpmi_nand_data *this = dev_get_drvdata(dev);
> +	int ret;
>  
> -	release_dma_channels(this);
> -	return 0;
> +	pinctrl_pm_select_sleep_state(dev);
> +	ret = pm_runtime_force_suspend(dev);
> +
> +	return ret;
>  }
>  
>  static int gpmi_pm_resume(struct device *dev)
> @@ -2711,9 +2718,13 @@ static int gpmi_pm_resume(struct device *dev)
>  	struct gpmi_nand_data *this = dev_get_drvdata(dev);
>  	int ret;
>  
> -	ret = acquire_dma_channels(this);
> -	if (ret < 0)
> +	ret = pm_runtime_force_resume(dev);
> +	if (ret) {
> +		dev_err(this->dev, "Error in resume %d\n", ret);
>  		return ret;
> +	}
> +
> +	pinctrl_pm_select_default_state(dev);
>  
>  	/* re-init the GPMI registers */
>  	ret = gpmi_init(this);
> @@ -2729,22 +2740,40 @@ static int gpmi_pm_resume(struct device *dev)
>  		return ret;
>  	}
>  
> +	/* re-apply the timing setting */
> +	this->hw.must_apply_timings = true;
> +
>  	return 0;
>  }
>  #endif /* CONFIG_PM_SLEEP */
>  
> -static int __maybe_unused gpmi_runtime_suspend(struct device *dev)
> +#define gpmi_enable_clk(x)	__gpmi_enable_clk(x, true)
> +#define gpmi_disable_clk(x)	__gpmi_enable_clk(x, false)
> +
> +static int gpmi_runtime_suspend(struct device *dev)
>  {
>  	struct gpmi_nand_data *this = dev_get_drvdata(dev);
>  
> -	return __gpmi_enable_clk(this, false);
> +	gpmi_disable_clk(this);
> +	release_dma_channels(this);
> +
> +	return 0;
>  }
>  
> -static int __maybe_unused gpmi_runtime_resume(struct device *dev)
> +static int gpmi_runtime_resume(struct device *dev)
>  {
>  	struct gpmi_nand_data *this = dev_get_drvdata(dev);
> +	int ret;
>  
> -	return __gpmi_enable_clk(this, true);
> +	ret = gpmi_enable_clk(this);
> +	if (ret)
> +		return ret;
> +
> +	ret = acquire_dma_channels(this);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
>  }
>  
>  static const struct dev_pm_ops gpmi_pm_ops = {




Thanks,
Miquèl

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Re: [PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue

[Esben Haabendal]

Miquel Raynal <miquel.raynal@bootlin.com> writes:

> Hi Esben, Han,
>
> Han Xu <han.xu@nxp.com> wrote on Fri, 10 Jan 2020 01:05:56 +0800:
>
>> fix several issues when system suspend/resume,
>> 
>> - leverage the runtime pm for system suspend/resume
>> - enable the clock before register access
>> - re-apply timing settings
>> - set the proper pinctrl state
>
> Esben are you fine with this patch?

It sounds like something that should probably be 4 separate patches.

> Or maybe Han you could take over Esben's patch and extend it?

I don't see why my two patches, which covers point 1 and 3 in the list
of issues covered by Han's patch, should not be merged.

Han, would you mind re-spin your patch to two separate patches covering
the remaining issues

 - enable the clock before register access
 - set the proper pinctrl state

/Esben

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Re: [PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue

[Han Xu]

On Thu, Jan 9, 2020 at 2:06 PM Esben Haabendal <esben@geanix.com> wrote:
>
> Miquel Raynal <miquel.raynal@bootlin.com> writes:
>
> > Hi Esben, Han,
> >
> > Han Xu <han.xu@nxp.com> wrote on Fri, 10 Jan 2020 01:05:56 +0800:
> >
> >> fix several issues when system suspend/resume,
> >>
> >> - leverage the runtime pm for system suspend/resume
> >> - enable the clock before register access
> >> - re-apply timing settings
> >> - set the proper pinctrl state
> >
> > Esben are you fine with this patch?
>
> It sounds like something that should probably be 4 separate patches.
>
> > Or maybe Han you could take over Esben's patch and extend it?
>
> I don't see why my two patches, which covers point 1 and 3 in the list
> of issues covered by Han's patch, should not be merged.
>
> Han, would you mind re-spin your patch to two separate patches covering
> the remaining issues

I am fine to keep your patches and re-spin the rest changes.

>
>  - enable the clock before register access
>  - set the proper pinctrl state
>
> /Esben
>
> ______________________________________________________
> Linux MTD discussion mailing list
> http://lists.infradead.org/mailman/listinfo/linux-mtd/



-- 
Sincerely,

Han XU

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Re: [PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue

[Esben Haabendal]

Hi Han

See comments/questions below.

If I understand the purpose of some of your changes correct, you are
fixing the handling of pm usage counter, as it currently is incremented
in gpmi_init() and decremented in gpmi_nand_remove().  I believe that
would be nice to have in a separate patch with an explanation of the
change.

Han Xu <han.xu@nxp.com> writes:

> fix several issues when system suspend/resume,
>
> - leverage the runtime pm for system suspend/resume
> - enable the clock before register access
> - re-apply timing settings
> - set the proper pinctrl state
>
> Signed-off-by: Han Xu <han.xu@nxp.com>
> ---
>  drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 59 ++++++++++++++++------
>  1 file changed, 44 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> index 334fe3130285..37437d47ab9a 100644
> --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> @@ -15,6 +15,7 @@
>  #include <linux/of.h>
>  #include <linux/of_device.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/pinctrl/consumer.h>
>  #include <linux/dma/mxs-dma.h>
>  #include "gpmi-nand.h"
>  #include "gpmi-regs.h"
> @@ -146,7 +147,11 @@ static int __gpmi_enable_clk(struct gpmi_nand_data *this, bool v)
>  static int gpmi_init(struct gpmi_nand_data *this)
>  {
>  	struct resources *r = &this->resources;
> -	int ret;
> +	int ret = 0;

I don't see why this is changed, given that ret is unconditionally
assigned in the next line.

> +
> +	ret = pm_runtime_get_sync(this->dev);
> +	if (ret < 0)
> +		return ret;
>  
>  	ret = gpmi_reset_block(r->gpmi_regs, false);
>  	if (ret)
> @@ -179,8 +184,10 @@ static int gpmi_init(struct gpmi_nand_data *this)
>  	 */
>  	writel(BM_GPMI_CTRL1_DECOUPLE_CS, r->gpmi_regs + HW_GPMI_CTRL1_SET);
>  
> -	return 0;

Please provide an explanation of the reasoning of this change is.

>  err_out:
> +	pm_runtime_mark_last_busy(this->dev);
> +	pm_runtime_put_autosuspend(this->dev);
> +
>  	return ret;
>  }
>  
> @@ -528,7 +535,7 @@ static int common_nfc_set_geometry(struct gpmi_nand_data *this)
>  static int bch_set_geometry(struct gpmi_nand_data *this)
>  {
>  	struct resources *r = &this->resources;
> -	int ret;
> +	int ret = 0;

I don't see any reason for this change.

>  	ret = common_nfc_set_geometry(this);
>  	if (ret)
> @@ -2676,7 +2682,7 @@ static int gpmi_nand_probe(struct platform_device *pdev)
>  	return 0;
>  
>  exit_nfc_init:
> -	pm_runtime_put(&pdev->dev);

I guess this is because of the change above that causes usage counter
not to be incremented in gpmi_init() when it is successful.

> +	pm_runtime_dont_use_autosuspend(&pdev->dev);

Is this required before pm_runtime_disable()?

>  	pm_runtime_disable(&pdev->dev);
>  	release_resources(this);
>  exit_acquire_resources:
> @@ -2688,7 +2694,6 @@ static int gpmi_nand_remove(struct platform_device *pdev)
>  {
>  	struct gpmi_nand_data *this = platform_get_drvdata(pdev);
>  
> -	pm_runtime_put_sync(&pdev->dev);

Should be covered by explanation of the change in gpmi_init().

>  	pm_runtime_disable(&pdev->dev);
>  
>  	nand_release(&this->nand);
> @@ -2700,10 +2705,12 @@ static int gpmi_nand_remove(struct platform_device *pdev)
>  #ifdef CONFIG_PM_SLEEP
>  static int gpmi_pm_suspend(struct device *dev)
>  {
> -	struct gpmi_nand_data *this = dev_get_drvdata(dev);
> +	int ret;
>  
> -	release_dma_channels(this);
> -	return 0;
> +	pinctrl_pm_select_sleep_state(dev);
> +	ret = pm_runtime_force_suspend(dev);
> +
> +	return ret;
>  }
>  
>  static int gpmi_pm_resume(struct device *dev)
> @@ -2711,9 +2718,13 @@ static int gpmi_pm_resume(struct device *dev)
>  	struct gpmi_nand_data *this = dev_get_drvdata(dev);
>  	int ret;
>  
> -	ret = acquire_dma_channels(this);
> -	if (ret < 0)
> +	ret = pm_runtime_force_resume(dev);
> +	if (ret) {
> +		dev_err(this->dev, "Error in resume %d\n", ret);
>  		return ret;
> +	}
> +
> +	pinctrl_pm_select_default_state(dev);
>  
>  	/* re-init the GPMI registers */
>  	ret = gpmi_init(this);
> @@ -2729,22 +2740,40 @@ static int gpmi_pm_resume(struct device *dev)
>  		return ret;
>  	}
>  
> +	/* re-apply the timing setting */
> +	this->hw.must_apply_timings = true;
> +
>  	return 0;
>  }
>  #endif /* CONFIG_PM_SLEEP */
>  
> -static int __maybe_unused gpmi_runtime_suspend(struct device *dev)
> +#define gpmi_enable_clk(x)	__gpmi_enable_clk(x, true)
> +#define gpmi_disable_clk(x)	__gpmi_enable_clk(x, false)
> +
> +static int gpmi_runtime_suspend(struct device *dev)
>  {
>  	struct gpmi_nand_data *this = dev_get_drvdata(dev);
>  
> -	return __gpmi_enable_clk(this, false);
> +	gpmi_disable_clk(this);
> +	release_dma_channels(this);
> +
> +	return 0;
>  }
>  
> -static int __maybe_unused gpmi_runtime_resume(struct device *dev)
> +static int gpmi_runtime_resume(struct device *dev)
>  {
>  	struct gpmi_nand_data *this = dev_get_drvdata(dev);
> +	int ret;
>  
> -	return __gpmi_enable_clk(this, true);
> +	ret = gpmi_enable_clk(this);
> +	if (ret)
> +		return ret;
> +
> +	ret = acquire_dma_channels(this);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
>  }
>  
>  static const struct dev_pm_ops gpmi_pm_ops = {

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Re: [PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue

[Miquel Raynal]

Hi Han,

Han Xu <xhnjupt@gmail.com> wrote on Thu, 9 Jan 2020 14:09:24 -0600:

> On Thu, Jan 9, 2020 at 2:06 PM Esben Haabendal <esben@geanix.com> wrote:
> >
> > Miquel Raynal <miquel.raynal@bootlin.com> writes:
> >  
> > > Hi Esben, Han,
> > >
> > > Han Xu <han.xu@nxp.com> wrote on Fri, 10 Jan 2020 01:05:56 +0800:
> > >  
> > >> fix several issues when system suspend/resume,
> > >>
> > >> - leverage the runtime pm for system suspend/resume
> > >> - enable the clock before register access
> > >> - re-apply timing settings
> > >> - set the proper pinctrl state  
> > >
> > > Esben are you fine with this patch?  
> >
> > It sounds like something that should probably be 4 separate patches.
> >  
> > > Or maybe Han you could take over Esben's patch and extend it?  
> >
> > I don't see why my two patches, which covers point 1 and 3 in the list
> > of issues covered by Han's patch, should not be merged.
> >
> > Han, would you mind re-spin your patch to two separate patches covering
> > the remaining issues  
> 
> I am fine to keep your patches and re-spin the rest changes.

Great, I'll queue Esben patches for 5.6 then.

Would you mind acking them?

Thanks,
Miquèl

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Re: [PATCH] mtd: rawnand: gpmi: fix the suspend/resume issue

[Han Xu]

On Thu, Jan 9, 2020 at 2:46 PM Esben Haabendal <esben@geanix.com> wrote:
>
> Hi Han
>
> See comments/questions below.
>
> If I understand the purpose of some of your changes correct, you are
> fixing the handling of pm usage counter, as it currently is incremented
> in gpmi_init() and decremented in gpmi_nand_remove().  I believe that
> would be nice to have in a separate patch with an explanation of the
> change.
>
> Han Xu <han.xu@nxp.com> writes:
>
> > fix several issues when system suspend/resume,
> >
> > - leverage the runtime pm for system suspend/resume
> > - enable the clock before register access
> > - re-apply timing settings
> > - set the proper pinctrl state
> >
> > Signed-off-by: Han Xu <han.xu@nxp.com>
> > ---
> >  drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 59 ++++++++++++++++------
> >  1 file changed, 44 insertions(+), 15 deletions(-)
> >
> > diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> > index 334fe3130285..37437d47ab9a 100644
> > --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> > +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> > @@ -15,6 +15,7 @@
> >  #include <linux/of.h>
> >  #include <linux/of_device.h>
> >  #include <linux/pm_runtime.h>
> > +#include <linux/pinctrl/consumer.h>
> >  #include <linux/dma/mxs-dma.h>
> >  #include "gpmi-nand.h"
> >  #include "gpmi-regs.h"
> > @@ -146,7 +147,11 @@ static int __gpmi_enable_clk(struct gpmi_nand_data *this, bool v)
> >  static int gpmi_init(struct gpmi_nand_data *this)
> >  {
> >       struct resources *r = &this->resources;
> > -     int ret;
> > +     int ret = 0;
>
> I don't see why this is changed, given that ret is unconditionally
> assigned in the next line.

removed.

>
> > +
> > +     ret = pm_runtime_get_sync(this->dev);
> > +     if (ret < 0)
> > +             return ret;
> >
> >       ret = gpmi_reset_block(r->gpmi_regs, false);
> >       if (ret)
> > @@ -179,8 +184,10 @@ static int gpmi_init(struct gpmi_nand_data *this)
> >        */
> >       writel(BM_GPMI_CTRL1_DECOUPLE_CS, r->gpmi_regs + HW_GPMI_CTRL1_SET);
> >
> > -     return 0;
>
> Please provide an explanation of the reasoning of this change is.

I prefer to pair all runtime ops in same function, get_sync before
register access and put after that, in all cases.

>
> >  err_out:
> > +     pm_runtime_mark_last_busy(this->dev);
> > +     pm_runtime_put_autosuspend(this->dev);
> > +
> >       return ret;
> >  }
> >
> > @@ -528,7 +535,7 @@ static int common_nfc_set_geometry(struct gpmi_nand_data *this)
> >  static int bch_set_geometry(struct gpmi_nand_data *this)
> >  {
> >       struct resources *r = &this->resources;
> > -     int ret;
> > +     int ret = 0;
>
> I don't see any reason for this change.

removed

>
> >       ret = common_nfc_set_geometry(this);
> >       if (ret)
> > @@ -2676,7 +2682,7 @@ static int gpmi_nand_probe(struct platform_device *pdev)
> >       return 0;
> >
> >  exit_nfc_init:
> > -     pm_runtime_put(&pdev->dev);
>
> I guess this is because of the change above that causes usage counter
> not to be incremented in gpmi_init() when it is successful.
>
> > +     pm_runtime_dont_use_autosuspend(&pdev->dev);
>
> Is this required before pm_runtime_disable()?

If probe function failed before runtime timeout, for instance, the
NAND chip not mounted, the runtime suspend won't be called without
this change.

>
> >       pm_runtime_disable(&pdev->dev);
> >       release_resources(this);
> >  exit_acquire_resources:
> > @@ -2688,7 +2694,6 @@ static int gpmi_nand_remove(struct platform_device *pdev)
> >  {
> >       struct gpmi_nand_data *this = platform_get_drvdata(pdev);
> >
> > -     pm_runtime_put_sync(&pdev->dev);
>
> Should be covered by explanation of the change in gpmi_init().
>
> >       pm_runtime_disable(&pdev->dev);
> >
> >       nand_release(&this->nand);
> > @@ -2700,10 +2705,12 @@ static int gpmi_nand_remove(struct platform_device *pdev)
> >  #ifdef CONFIG_PM_SLEEP
> >  static int gpmi_pm_suspend(struct device *dev)
> >  {
> > -     struct gpmi_nand_data *this = dev_get_drvdata(dev);
> > +     int ret;
> >
> > -     release_dma_channels(this);
> > -     return 0;
> > +     pinctrl_pm_select_sleep_state(dev);
> > +     ret = pm_runtime_force_suspend(dev);
> > +
> > +     return ret;
> >  }
> >
> >  static int gpmi_pm_resume(struct device *dev)
> > @@ -2711,9 +2718,13 @@ static int gpmi_pm_resume(struct device *dev)
> >       struct gpmi_nand_data *this = dev_get_drvdata(dev);
> >       int ret;
> >
> > -     ret = acquire_dma_channels(this);
> > -     if (ret < 0)
> > +     ret = pm_runtime_force_resume(dev);
> > +     if (ret) {
> > +             dev_err(this->dev, "Error in resume %d\n", ret);
> >               return ret;
> > +     }
> > +
> > +     pinctrl_pm_select_default_state(dev);
> >
> >       /* re-init the GPMI registers */
> >       ret = gpmi_init(this);
> > @@ -2729,22 +2740,40 @@ static int gpmi_pm_resume(struct device *dev)
> >               return ret;
> >       }
> >
> > +     /* re-apply the timing setting */
> > +     this->hw.must_apply_timings = true;
> > +
> >       return 0;
> >  }
> >  #endif /* CONFIG_PM_SLEEP */
> >
> > -static int __maybe_unused gpmi_runtime_suspend(struct device *dev)
> > +#define gpmi_enable_clk(x)   __gpmi_enable_clk(x, true)
> > +#define gpmi_disable_clk(x)  __gpmi_enable_clk(x, false)
> > +
> > +static int gpmi_runtime_suspend(struct device *dev)
> >  {
> >       struct gpmi_nand_data *this = dev_get_drvdata(dev);
> >
> > -     return __gpmi_enable_clk(this, false);
> > +     gpmi_disable_clk(this);
> > +     release_dma_channels(this);
> > +
> > +     return 0;
> >  }
> >
> > -static int __maybe_unused gpmi_runtime_resume(struct device *dev)
> > +static int gpmi_runtime_resume(struct device *dev)
> >  {
> >       struct gpmi_nand_data *this = dev_get_drvdata(dev);
> > +     int ret;
> >
> > -     return __gpmi_enable_clk(this, true);
> > +     ret = gpmi_enable_clk(this);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = acquire_dma_channels(this);
> > +     if (ret < 0)
> > +             return ret;
> > +
> > +     return 0;
> >  }
> >
> >  static const struct dev_pm_ops gpmi_pm_ops = {
>
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-- 
Sincerely,

Han XU

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