[PATCH 1/2] pinctrl: tegra: add suspend-resume support

[PATCH 1/2] pinctrl: tegra: add suspend-resume support

[Bibek Basu]

From: Pritesh Raithatha <praithatha-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>

This patch adds suspend and resume callbacks to the pinctrl-tegra driver.

Signed-off-by: Pritesh Raithatha <praithatha-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Bibek Basu <bbasu-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
 drivers/pinctrl/pinctrl-tegra.c    | 56 ++++++++++++++++++++++++++++++++++++--
 drivers/pinctrl/pinctrl-tegra.h    |  3 +-
 drivers/pinctrl/pinctrl-tegra114.c |  3 ++
 drivers/pinctrl/pinctrl-tegra20.c  |  3 ++
 drivers/pinctrl/pinctrl-tegra30.c  |  2 ++
 5 files changed, 64 insertions(+), 3 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-tegra.c b/drivers/pinctrl/pinctrl-tegra.c
index f195d77..16ffd79 100644
--- a/drivers/pinctrl/pinctrl-tegra.c
+++ b/drivers/pinctrl/pinctrl-tegra.c
@@ -29,6 +29,7 @@
 #include <linux/pinctrl/pinmux.h>
 #include <linux/pinctrl/pinconf.h>
 #include <linux/slab.h>
+#include <linux/pm.h>
 
 #include "core.h"
 #include "pinctrl-tegra.h"
@@ -41,6 +42,8 @@ struct tegra_pmx {
 
 	int nbanks;
 	void __iomem **regs;
+	int *regs_size;
+	u32 *pg_data;
 };
 
 static inline u32 pmx_readl(struct tegra_pmx *pmx, u32 bank, u32 reg)
@@ -701,12 +704,42 @@ static struct pinctrl_desc tegra_pinctrl_desc = {
 	.owner = THIS_MODULE,
 };
 
+int pinctrl_suspend(struct device *dev)
+{
+	int i, j;
+	struct tegra_pmx *pmx = dev_get_drvdata(dev);
+	u32 *pg_data = pmx->pg_data;
+	u32 *regs;
+
+	for (i = 0; i < pmx->nbanks; i++) {
+		regs = pmx->regs[i];
+		for (j = 0; j < pmx->regs_size[i] / 4; j++)
+			*pg_data++ = readl(regs++);
+	}
+	return 0;
+}
+
+int pinctrl_resume(struct device *dev)
+{
+	int i, j;
+	struct tegra_pmx *pmx = dev_get_drvdata(dev);
+	u32 *pg_data = pmx->pg_data;
+	u32 *regs;
+
+	for (i = 0; i < pmx->nbanks; i++) {
+		regs = pmx->regs[i];
+		for (j = 0; j < pmx->regs_size[i] / 4; j++)
+			writel(*pg_data++, regs++);
+	}
+	return 0;
+}
+
 int tegra_pinctrl_probe(struct platform_device *pdev,
 			const struct tegra_pinctrl_soc_data *soc_data)
 {
-	struct tegra_pmx *pmx;
 	struct resource *res;
-	int i;
+	struct tegra_pmx *pmx;
+	int i, pg_data_size = 0;
 
 	pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
 	if (!pmx) {
@@ -725,6 +758,7 @@ int tegra_pinctrl_probe(struct platform_device *pdev,
 		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
 		if (!res)
 			break;
+		pg_data_size += resource_size(res);
 	}
 	pmx->nbanks = i;
 
@@ -735,6 +769,21 @@ int tegra_pinctrl_probe(struct platform_device *pdev,
 		return -ENODEV;
 	}
 
+if (IS_ENABLED(CONFIG_PM_SLEEP))
+	pmx->regs_size = devm_kzalloc(&pdev->dev,
+				pmx->nbanks * sizeof(*(pmx->regs_size)),
+				GFP_KERNEL);
+	if (!pmx->regs_size) {
+		dev_err(&pdev->dev, "Can't alloc regs pointer\n");
+		return -ENODEV;
+	}
+
+	pmx->pg_data = devm_kzalloc(&pdev->dev, pg_data_size, GFP_KERNEL);
+	if (!pmx->pg_data) {
+		dev_err(&pdev->dev, "Can't alloc pingroup data pointer\n");
+		return -ENODEV;
+	}
+
 	for (i = 0; i < pmx->nbanks; i++) {
 		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
 		if (!res) {
@@ -756,6 +805,9 @@ int tegra_pinctrl_probe(struct platform_device *pdev,
 			dev_err(&pdev->dev, "Couldn't ioremap regs %d\n", i);
 			return -ENODEV;
 		}
+
+if (IS_ENABLED(CONFIG_PM_SLEEP))
+		pmx->regs_size[i] = resource_size(res);
 	}
 
 	pmx->pctl = pinctrl_register(&tegra_pinctrl_desc, &pdev->dev, pmx);
diff --git a/drivers/pinctrl/pinctrl-tegra.h b/drivers/pinctrl/pinctrl-tegra.h
index 817f706..71616c7 100644
--- a/drivers/pinctrl/pinctrl-tegra.h
+++ b/drivers/pinctrl/pinctrl-tegra.h
@@ -202,5 +202,6 @@ struct tegra_pinctrl_soc_data {
 int tegra_pinctrl_probe(struct platform_device *pdev,
 			const struct tegra_pinctrl_soc_data *soc_data);
 int tegra_pinctrl_remove(struct platform_device *pdev);
-
+int pinctrl_suspend(struct device *dev);
+int pinctrl_resume(struct device *dev);
 #endif
diff --git a/drivers/pinctrl/pinctrl-tegra114.c b/drivers/pinctrl/pinctrl-tegra114.c
index 622c485..9641588 100644
--- a/drivers/pinctrl/pinctrl-tegra114.c
+++ b/drivers/pinctrl/pinctrl-tegra114.c
@@ -2752,10 +2752,13 @@ static struct of_device_id tegra114_pinctrl_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, tegra114_pinctrl_of_match);
 
+static SIMPLE_DEV_PM_OPS(pinctrl_dev_pm_ops, pinctrl_suspend, pinctrl_resume);
+
 static struct platform_driver tegra114_pinctrl_driver = {
 	.driver = {
 		.name = "tegra114-pinctrl",
 		.owner = THIS_MODULE,
+		.pm = &pinctrl_dev_pm_ops,
 		.of_match_table = tegra114_pinctrl_of_match,
 	},
 	.probe = tegra114_pinctrl_probe,
diff --git a/drivers/pinctrl/pinctrl-tegra20.c b/drivers/pinctrl/pinctrl-tegra20.c
index fcfb7d0..ea45ad5 100644
--- a/drivers/pinctrl/pinctrl-tegra20.c
+++ b/drivers/pinctrl/pinctrl-tegra20.c
@@ -2872,10 +2872,13 @@ static struct of_device_id tegra20_pinctrl_of_match[] = {
 	{ },
 };
 
+static SIMPLE_DEV_PM_OPS(pinctrl_dev_pm_ops, pinctrl_suspend, pinctrl_resume);
+
 static struct platform_driver tegra20_pinctrl_driver = {
 	.driver = {
 		.name = "tegra20-pinctrl",
 		.owner = THIS_MODULE,
+		.pm = &pinctrl_dev_pm_ops,
 		.of_match_table = tegra20_pinctrl_of_match,
 	},
 	.probe = tegra20_pinctrl_probe,
diff --git a/drivers/pinctrl/pinctrl-tegra30.c b/drivers/pinctrl/pinctrl-tegra30.c
index 2300deb..11899d4 100644
--- a/drivers/pinctrl/pinctrl-tegra30.c
+++ b/drivers/pinctrl/pinctrl-tegra30.c
@@ -3736,6 +3736,8 @@ static struct of_device_id tegra30_pinctrl_of_match[] = {
 	{ },
 };
 
+static SIMPLE_DEV_PM_OPS(pinctrl_dev_pm_ops, pinctrl_suspend, pinctrl_resume);
+
 static struct platform_driver tegra30_pinctrl_driver = {
 	.driver = {
 		.name = "tegra30-pinctrl",
-- 
1.8.1.5

[PATCH 2/2] ARM: DT: tegra: pinctrl suspend resume hook

[Bibek Basu]

Make pinmux as the first node of tegra DT
so as to achieve pinctrl as last device to suspend and
first device to resume.

Signed-off-by: Bibek Basu <bbasu-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
 arch/arm/boot/dts/tegra114.dtsi | 12 ++++++------
 arch/arm/boot/dts/tegra20.dtsi  | 16 ++++++++--------
 arch/arm/boot/dts/tegra30.dtsi  | 13 +++++++------
 3 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/arch/arm/boot/dts/tegra114.dtsi b/arch/arm/boot/dts/tegra114.dtsi
index a58a761..36596ae 100644
--- a/arch/arm/boot/dts/tegra114.dtsi
+++ b/arch/arm/boot/dts/tegra114.dtsi
@@ -11,6 +11,12 @@
 		serial3 = &uartd;
 	};
 
+	pinmux: pinmux {
+		compatible = "nvidia,tegra114-pinmux";
+		reg = <0x70000868 0x148		/* Pad control registers */
+		       0x70003000 0x40c>;	/* Mux registers */
+	};
+
 	host1x {
 		compatible = "nvidia,tegra114-host1x", "simple-bus";
 		reg = <0x50000000 0x00028000>;
@@ -165,12 +171,6 @@
 		interrupt-controller;
 	};
 
-	pinmux: pinmux {
-		compatible = "nvidia,tegra114-pinmux";
-		reg = <0x70000868 0x148		/* Pad control registers */
-		       0x70003000 0x40c>;	/* Mux registers */
-	};
-
 	/*
 	 * There are two serial driver i.e. 8250 based simple serial
 	 * driver and APB DMA based serial driver for higher baudrate
diff --git a/arch/arm/boot/dts/tegra20.dtsi b/arch/arm/boot/dts/tegra20.dtsi
index a5a9615..6d8a663 100644
--- a/arch/arm/boot/dts/tegra20.dtsi
+++ b/arch/arm/boot/dts/tegra20.dtsi
@@ -12,6 +12,14 @@
 		serial4 = &uarte;
 	};
 
+	pinmux: pinmux {
+		compatible = "nvidia,tegra20-pinmux";
+		reg = <0x70000014 0x10   /* Tri-state registers */
+		       0x70000080 0x20   /* Mux registers */
+		       0x700000a0 0x14   /* Pull-up/down registers */
+		       0x70000868 0xa8>; /* Pad control registers */
+	};
+
 	host1x {
 		compatible = "nvidia,tegra20-host1x", "simple-bus";
 		reg = <0x50000000 0x00024000>;
@@ -196,14 +204,6 @@
 		interrupt-controller;
 	};
 
-	pinmux: pinmux {
-		compatible = "nvidia,tegra20-pinmux";
-		reg = <0x70000014 0x10   /* Tri-state registers */
-		       0x70000080 0x20   /* Mux registers */
-		       0x700000a0 0x14   /* Pull-up/down registers */
-		       0x70000868 0xa8>; /* Pad control registers */
-	};
-
 	das {
 		compatible = "nvidia,tegra20-das";
 		reg = <0x70000c00 0x80>;
diff --git a/arch/arm/boot/dts/tegra30.dtsi b/arch/arm/boot/dts/tegra30.dtsi
index 9f33086..b4b79f0 100644
--- a/arch/arm/boot/dts/tegra30.dtsi
+++ b/arch/arm/boot/dts/tegra30.dtsi
@@ -12,6 +12,13 @@
 		serial4 = &uarte;
 	};
 
+	pinmux: pinmux {
+		compatible = "nvidia,tegra30-pinmux";
+		reg = <0x70000868 0xd4    /* Pad control registers */
+		       0x70003000 0x3e4>; /* Mux registers */
+	};
+
+
 	host1x {
 		compatible = "nvidia,tegra30-host1x", "simple-bus";
 		reg = <0x50000000 0x00024000>;
@@ -216,12 +223,6 @@
 		interrupt-controller;
 	};
 
-	pinmux: pinmux {
-		compatible = "nvidia,tegra30-pinmux";
-		reg = <0x70000868 0xd4    /* Pad control registers */
-		       0x70003000 0x3e4>; /* Mux registers */
-	};
-
 	/*
 	 * There are two serial driver i.e. 8250 based simple serial
 	 * driver and APB DMA based serial driver for higher baudrate
-- 
1.8.1.5

Re: [PATCH 1/2] pinctrl: tegra: add suspend-resume support

[Thierry Reding]

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> diff --git a/drivers/pinctrl/pinctrl-tegra.c b/drivers/pinctrl/pinctrl-tegra.c
[...]
> @@ -41,6 +42,8 @@ struct tegra_pmx {
>  
>  	int nbanks;
>  	void __iomem **regs;
> +	int *regs_size;

Perhaps this should be unsigned int *. The values stored in this array
will never be negative, right?

>  int tegra_pinctrl_probe(struct platform_device *pdev,
>  			const struct tegra_pinctrl_soc_data *soc_data)
>  {
> -	struct tegra_pmx *pmx;
>  	struct resource *res;
> -	int i;
> +	struct tegra_pmx *pmx;
> +	int i, pg_data_size = 0;

There's a needless move of the pmx variable declaration here.

> @@ -735,6 +769,21 @@ int tegra_pinctrl_probe(struct platform_device *pdev,
>  		return -ENODEV;
>  	}
>  
> +if (IS_ENABLED(CONFIG_PM_SLEEP))
> +	pmx->regs_size = devm_kzalloc(&pdev->dev,
> +				pmx->nbanks * sizeof(*(pmx->regs_size)),
> +				GFP_KERNEL);
> +	if (!pmx->regs_size) {
> +		dev_err(&pdev->dev, "Can't alloc regs pointer\n");
> +		return -ENODEV;
> +	}
> +
> +	pmx->pg_data = devm_kzalloc(&pdev->dev, pg_data_size, GFP_KERNEL);
> +	if (!pmx->pg_data) {
> +		dev_err(&pdev->dev, "Can't alloc pingroup data pointer\n");
> +		return -ENODEV;
> +	}

I don't think this works the way you expect it to. The line

	if (IS_ENABLED(CONFIG_PM_SLEEP))

is a standard conditional and therefore needs to be properly indented
and use { and } to delimit the block.

> @@ -756,6 +805,9 @@ int tegra_pinctrl_probe(struct platform_device *pdev,
>  			dev_err(&pdev->dev, "Couldn't ioremap regs %d\n", i);
>  			return -ENODEV;
>  		}
> +
> +if (IS_ENABLED(CONFIG_PM_SLEEP))
> +		pmx->regs_size[i] = resource_size(res);

In this case it will actually work as expected, but the if () should be
properly indented.

Thierry

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Re: [PATCH 2/2] ARM: DT: tegra: pinctrl suspend resume hook

[Thierry Reding]

[-- Attachment #1: Type: text/plain, Size: 4489 bytes --]

On Tue, Apr 23, 2013 at 11:39:02PM +0530, Bibek Basu wrote:
> Make pinmux as the first node of tegra DT
> so as to achieve pinctrl as last device to suspend and
> first device to resume.

I don't think this is a good idea. For one it encodes Linux specific
implementation details within the device tree. Furthermore I seem to
remember that the device tree makes no guarantees that the order of
nodes in the blob is the same as the order in the DTS.

That said I don't have a good alternative. Perhaps one solution would be
to use suspend_late() and resume_early() for the pinmux driver since
they will be called after and before the suspend() and resume()
callbacks of all other devices, respectively. Other than that I wasn't
able to find anything about forcing a particular order during suspend
and resume.

Cc'ing Rafael and the linux-pm mailing list, maybe somebody among them
knows a proper solution.

Thierry

> 
> Signed-off-by: Bibek Basu <bbasu@nvidia.com>
> ---
>  arch/arm/boot/dts/tegra114.dtsi | 12 ++++++------
>  arch/arm/boot/dts/tegra20.dtsi  | 16 ++++++++--------
>  arch/arm/boot/dts/tegra30.dtsi  | 13 +++++++------
>  3 files changed, 21 insertions(+), 20 deletions(-)
> 
> diff --git a/arch/arm/boot/dts/tegra114.dtsi b/arch/arm/boot/dts/tegra114.dtsi
> index a58a761..36596ae 100644
> --- a/arch/arm/boot/dts/tegra114.dtsi
> +++ b/arch/arm/boot/dts/tegra114.dtsi
> @@ -11,6 +11,12 @@
>  		serial3 = &uartd;
>  	};
>  
> +	pinmux: pinmux {
> +		compatible = "nvidia,tegra114-pinmux";
> +		reg = <0x70000868 0x148		/* Pad control registers */
> +		       0x70003000 0x40c>;	/* Mux registers */
> +	};
> +
>  	host1x {
>  		compatible = "nvidia,tegra114-host1x", "simple-bus";
>  		reg = <0x50000000 0x00028000>;
> @@ -165,12 +171,6 @@
>  		interrupt-controller;
>  	};
>  
> -	pinmux: pinmux {
> -		compatible = "nvidia,tegra114-pinmux";
> -		reg = <0x70000868 0x148		/* Pad control registers */
> -		       0x70003000 0x40c>;	/* Mux registers */
> -	};
> -
>  	/*
>  	 * There are two serial driver i.e. 8250 based simple serial
>  	 * driver and APB DMA based serial driver for higher baudrate
> diff --git a/arch/arm/boot/dts/tegra20.dtsi b/arch/arm/boot/dts/tegra20.dtsi
> index a5a9615..6d8a663 100644
> --- a/arch/arm/boot/dts/tegra20.dtsi
> +++ b/arch/arm/boot/dts/tegra20.dtsi
> @@ -12,6 +12,14 @@
>  		serial4 = &uarte;
>  	};
>  
> +	pinmux: pinmux {
> +		compatible = "nvidia,tegra20-pinmux";
> +		reg = <0x70000014 0x10   /* Tri-state registers */
> +		       0x70000080 0x20   /* Mux registers */
> +		       0x700000a0 0x14   /* Pull-up/down registers */
> +		       0x70000868 0xa8>; /* Pad control registers */
> +	};
> +
>  	host1x {
>  		compatible = "nvidia,tegra20-host1x", "simple-bus";
>  		reg = <0x50000000 0x00024000>;
> @@ -196,14 +204,6 @@
>  		interrupt-controller;
>  	};
>  
> -	pinmux: pinmux {
> -		compatible = "nvidia,tegra20-pinmux";
> -		reg = <0x70000014 0x10   /* Tri-state registers */
> -		       0x70000080 0x20   /* Mux registers */
> -		       0x700000a0 0x14   /* Pull-up/down registers */
> -		       0x70000868 0xa8>; /* Pad control registers */
> -	};
> -
>  	das {
>  		compatible = "nvidia,tegra20-das";
>  		reg = <0x70000c00 0x80>;
> diff --git a/arch/arm/boot/dts/tegra30.dtsi b/arch/arm/boot/dts/tegra30.dtsi
> index 9f33086..b4b79f0 100644
> --- a/arch/arm/boot/dts/tegra30.dtsi
> +++ b/arch/arm/boot/dts/tegra30.dtsi
> @@ -12,6 +12,13 @@
>  		serial4 = &uarte;
>  	};
>  
> +	pinmux: pinmux {
> +		compatible = "nvidia,tegra30-pinmux";
> +		reg = <0x70000868 0xd4    /* Pad control registers */
> +		       0x70003000 0x3e4>; /* Mux registers */
> +	};
> +
> +
>  	host1x {
>  		compatible = "nvidia,tegra30-host1x", "simple-bus";
>  		reg = <0x50000000 0x00024000>;
> @@ -216,12 +223,6 @@
>  		interrupt-controller;
>  	};
>  
> -	pinmux: pinmux {
> -		compatible = "nvidia,tegra30-pinmux";
> -		reg = <0x70000868 0xd4    /* Pad control registers */
> -		       0x70003000 0x3e4>; /* Mux registers */
> -	};
> -
>  	/*
>  	 * There are two serial driver i.e. 8250 based simple serial
>  	 * driver and APB DMA based serial driver for higher baudrate
> -- 
> 1.8.1.5
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-tegra" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> 

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RE: [PATCH 1/2] pinctrl: tegra: add suspend-resume support

[Bibek Basu]

> -----Original Message-----
> From: Thierry Reding [mailto:thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org]
> Sent: Wednesday, April 24, 2013 12:14 AM
> To: Bibek Basu
> Cc: linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org; swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org; linux-
> tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; Pritesh Raithatha
> Subject: Re: [PATCH 1/2] pinctrl: tegra: add suspend-resume support
> 
> * PGP Signed by an unknown key
> 
> > diff --git a/drivers/pinctrl/pinctrl-tegra.c
> > b/drivers/pinctrl/pinctrl-tegra.c
> [...]
> > @@ -41,6 +42,8 @@ struct tegra_pmx {
> >
> >  	int nbanks;
> >  	void __iomem **regs;
> > +	int *regs_size;
> 
> Perhaps this should be unsigned int *. The values stored in this array will
> never be negative, right?
Agree. 
> 
> >  int tegra_pinctrl_probe(struct platform_device *pdev,
> >  			const struct tegra_pinctrl_soc_data *soc_data)  {
> > -	struct tegra_pmx *pmx;
> >  	struct resource *res;
> > -	int i;
> > +	struct tegra_pmx *pmx;
> > +	int i, pg_data_size = 0;
> 
> There's a needless move of the pmx variable declaration here.
Agree
> 
> > @@ -735,6 +769,21 @@ int tegra_pinctrl_probe(struct platform_device
> *pdev,
> >  		return -ENODEV;
> >  	}
> >
> > +if (IS_ENABLED(CONFIG_PM_SLEEP))
> > +	pmx->regs_size = devm_kzalloc(&pdev->dev,
> > +				pmx->nbanks * sizeof(*(pmx->regs_size)),
> > +				GFP_KERNEL);
> > +	if (!pmx->regs_size) {
> > +		dev_err(&pdev->dev, "Can't alloc regs pointer\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	pmx->pg_data = devm_kzalloc(&pdev->dev, pg_data_size,
> GFP_KERNEL);
> > +	if (!pmx->pg_data) {
> > +		dev_err(&pdev->dev, "Can't alloc pingroup data pointer\n");
> > +		return -ENODEV;
> > +	}
> 
> I don't think this works the way you expect it to. The line
> 
> 	if (IS_ENABLED(CONFIG_PM_SLEEP))
> 
> is a standard conditional and therefore needs to be properly indented and
> use { and } to delimit the block.
> 
My Bad. Will fix
> > @@ -756,6 +805,9 @@ int tegra_pinctrl_probe(struct platform_device
> *pdev,
> >  			dev_err(&pdev->dev, "Couldn't ioremap regs %d\n",
> i);
> >  			return -ENODEV;
> >  		}
> > +
> > +if (IS_ENABLED(CONFIG_PM_SLEEP))
> > +		pmx->regs_size[i] = resource_size(res);
> 
> In this case it will actually work as expected, but the if () should be properly
> indented.
> 
> Thierry
> 
Thanks for the review
Bibek
> * Unknown Key
> * 0x7F3EB3A1

RE: [PATCH 2/2] ARM: DT: tegra: pinctrl suspend resume hook

[Bibek Basu]

> -----Original Message-----
> From: Thierry Reding [mailto:thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org]
> Sent: Saturday, April 27, 2013 1:19 AM
> To: Bibek Basu
> Cc: Rafael J. Wysocki; linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org; swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org;
> linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; linux-
> pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> Subject: Re: [PATCH 2/2] ARM: DT: tegra: pinctrl suspend resume hook
> 
> * PGP Signed by an unknown key
> 
> On Tue, Apr 23, 2013 at 11:39:02PM +0530, Bibek Basu wrote:
> > Make pinmux as the first node of tegra DT so as to achieve pinctrl as
> > last device to suspend and first device to resume.
> 
> I don't think this is a good idea. For one it encodes Linux specific
> implementation details within the device tree. Furthermore I seem to
> remember that the device tree makes no guarantees that the order of nodes
> in the blob is the same as the order in the DTS.
> 
> That said I don't have a good alternative. Perhaps one solution would be to
> use suspend_late() and resume_early() for the pinmux driver since they will
> be called after and before the suspend() and resume() callbacks of all other
> devices, respectively. Other than that I wasn't able to find anything about
> forcing a particular order during suspend and resume.
> 
> Cc'ing Rafael and the linux-pm mailing list, maybe somebody among them
> knows a proper solution.
> 
Stephen actually suggested me earlier to add dummy pinmux state on all dependent devices node. And that will make sure that dependency of driver prevails.
I tried that but I was not getting the desired result.
Can anyone tell me correct syntax for adding dummy state?

Regards
Bibek

> Thierry
> 
> >
> > Signed-off-by: Bibek Basu <bbasu-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> > ---
> >  arch/arm/boot/dts/tegra114.dtsi | 12 ++++++------
> > arch/arm/boot/dts/tegra20.dtsi  | 16 ++++++++--------
> > arch/arm/boot/dts/tegra30.dtsi  | 13 +++++++------
> >  3 files changed, 21 insertions(+), 20 deletions(-)
> >
> > diff --git a/arch/arm/boot/dts/tegra114.dtsi
> > b/arch/arm/boot/dts/tegra114.dtsi index a58a761..36596ae 100644
> > --- a/arch/arm/boot/dts/tegra114.dtsi
> > +++ b/arch/arm/boot/dts/tegra114.dtsi
> > @@ -11,6 +11,12 @@
> >  		serial3 = &uartd;
> >  	};
> >
> > +	pinmux: pinmux {
> > +		compatible = "nvidia,tegra114-pinmux";
> > +		reg = <0x70000868 0x148		/* Pad control
> registers */
> > +		       0x70003000 0x40c>;	/* Mux registers */
> > +	};
> > +
> >  	host1x {
> >  		compatible = "nvidia,tegra114-host1x", "simple-bus";
> >  		reg = <0x50000000 0x00028000>;
> > @@ -165,12 +171,6 @@
> >  		interrupt-controller;
> >  	};
> >
> > -	pinmux: pinmux {
> > -		compatible = "nvidia,tegra114-pinmux";
> > -		reg = <0x70000868 0x148		/* Pad control
> registers */
> > -		       0x70003000 0x40c>;	/* Mux registers */
> > -	};
> > -
> >  	/*
> >  	 * There are two serial driver i.e. 8250 based simple serial
> >  	 * driver and APB DMA based serial driver for higher baudrate diff
> > --git a/arch/arm/boot/dts/tegra20.dtsi
> > b/arch/arm/boot/dts/tegra20.dtsi index a5a9615..6d8a663 100644
> > --- a/arch/arm/boot/dts/tegra20.dtsi
> > +++ b/arch/arm/boot/dts/tegra20.dtsi
> > @@ -12,6 +12,14 @@
> >  		serial4 = &uarte;
> >  	};
> >
> > +	pinmux: pinmux {
> > +		compatible = "nvidia,tegra20-pinmux";
> > +		reg = <0x70000014 0x10   /* Tri-state registers */
> > +		       0x70000080 0x20   /* Mux registers */
> > +		       0x700000a0 0x14   /* Pull-up/down registers */
> > +		       0x70000868 0xa8>; /* Pad control registers */
> > +	};
> > +
> >  	host1x {
> >  		compatible = "nvidia,tegra20-host1x", "simple-bus";
> >  		reg = <0x50000000 0x00024000>;
> > @@ -196,14 +204,6 @@
> >  		interrupt-controller;
> >  	};
> >
> > -	pinmux: pinmux {
> > -		compatible = "nvidia,tegra20-pinmux";
> > -		reg = <0x70000014 0x10   /* Tri-state registers */
> > -		       0x70000080 0x20   /* Mux registers */
> > -		       0x700000a0 0x14   /* Pull-up/down registers */
> > -		       0x70000868 0xa8>; /* Pad control registers */
> > -	};
> > -
> >  	das {
> >  		compatible = "nvidia,tegra20-das";
> >  		reg = <0x70000c00 0x80>;
> > diff --git a/arch/arm/boot/dts/tegra30.dtsi
> > b/arch/arm/boot/dts/tegra30.dtsi index 9f33086..b4b79f0 100644
> > --- a/arch/arm/boot/dts/tegra30.dtsi
> > +++ b/arch/arm/boot/dts/tegra30.dtsi
> > @@ -12,6 +12,13 @@
> >  		serial4 = &uarte;
> >  	};
> >
> > +	pinmux: pinmux {
> > +		compatible = "nvidia,tegra30-pinmux";
> > +		reg = <0x70000868 0xd4    /* Pad control registers */
> > +		       0x70003000 0x3e4>; /* Mux registers */
> > +	};
> > +
> > +
> >  	host1x {
> >  		compatible = "nvidia,tegra30-host1x", "simple-bus";
> >  		reg = <0x50000000 0x00024000>;
> > @@ -216,12 +223,6 @@
> >  		interrupt-controller;
> >  	};
> >
> > -	pinmux: pinmux {
> > -		compatible = "nvidia,tegra30-pinmux";
> > -		reg = <0x70000868 0xd4    /* Pad control registers */
> > -		       0x70003000 0x3e4>; /* Mux registers */
> > -	};
> > -
> >  	/*
> >  	 * There are two serial driver i.e. 8250 based simple serial
> >  	 * driver and APB DMA based serial driver for higher baudrate
> > --
> > 1.8.1.5
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-tegra"
> > in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More
> majordomo
> > info at  http://vger.kernel.org/majordomo-info.html
> >
> >
> 
> * Unknown Key
> * 0x7F3EB3A1

Re: [PATCH 2/2] ARM: DT: tegra: pinctrl suspend resume hook

[Stephen Warren]

On 04/28/2013 07:42 AM, Bibek Basu wrote:
>> -----Original Message-----
>> From: Thierry Reding [mailto:thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org]
>> Sent: Saturday, April 27, 2013 1:19 AM
>> To: Bibek Basu
>> Cc: Rafael J. Wysocki; linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org; swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org;
>> linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; linux-
>> pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>> Subject: Re: [PATCH 2/2] ARM: DT: tegra: pinctrl suspend resume hook
>>
>> * PGP Signed by an unknown key
>>
>> On Tue, Apr 23, 2013 at 11:39:02PM +0530, Bibek Basu wrote:
>>> Make pinmux as the first node of tegra DT so as to achieve pinctrl as
>>> last device to suspend and first device to resume.
>>
>> I don't think this is a good idea. For one it encodes Linux specific
>> implementation details within the device tree. Furthermore I seem to
>> remember that the device tree makes no guarantees that the order of nodes
>> in the blob is the same as the order in the DTS.
>>
>> That said I don't have a good alternative. Perhaps one solution would be to
>> use suspend_late() and resume_early() for the pinmux driver since they will
>> be called after and before the suspend() and resume() callbacks of all other
>> devices, respectively. Other than that I wasn't able to find anything about
>> forcing a particular order during suspend and resume.
>>
>> Cc'ing Rafael and the linux-pm mailing list, maybe somebody among them
>> knows a proper solution.
>
> Stephen actually suggested me earlier to add dummy pinmux state on all dependent devices node. And that will make sure that dependency of driver prevails.
> I tried that but I was not getting the desired result.
> Can anyone tell me correct syntax for adding dummy state?

I agree with Thierry that this patch is not the correct approach.

A dummy pinctrl state would look something like the following in each
affected device node:

                pinctrl-names = "default";
                pinctrl-0 = <>;