[PATCH 1/3] i2c: tegra: Support DVC controller in device tree

[PATCH 1/3] i2c: tegra: Support DVC controller in device tree

[Stephen Warren]

One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller)
block. This block is identical to the rest of the I2C blocks, except that
it only supports master mode, it has registers moved around, and it needs
some extra init to get it into I2C mode.  The register moves are handled
by i2c_readl and i2c_writel

This patch adds a new compatible value for controllers of this "DVC"
type; I figured that this approach was reasonable, as opposed to adding
an is-dvc property under the existing compatible value, since the HW
truly is different.

Signed-off-by: Stephen Warren <swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
Ben, it'd probably be simplest if you could ack this patch, and we
could take it through the Tegra tree.

 drivers/i2c/busses/i2c-tegra.c |   37 +++++++++++++++++++++++++------------
 1 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 46b6500..c264e8c 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -26,6 +26,7 @@
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/i2c-tegra.h>
+#include <linux/of_device.h>
 #include <linux/of_i2c.h>
 #include <linux/module.h>
 
@@ -558,6 +559,18 @@ static const struct i2c_algorithm tegra_i2c_algo = {
 	.functionality	= tegra_i2c_func,
 };
 
+#if defined(CONFIG_OF)
+/* Match table for of_platform binding */
+static const struct of_device_id tegra_i2c_of_match[] __devinitconst = {
+	{ .compatible = "nvidia,tegra20-i2c",     .data = (void *)0},
+	{ .compatible = "nvidia,tegra20-i2c-dvc", .data = (void *)1},
+	{},
+};
+MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
+#else
+#define tegra_i2c_of_match NULL
+#endif
+
 static int tegra_i2c_probe(struct platform_device *pdev)
 {
 	struct tegra_i2c_dev *i2c_dev;
@@ -636,7 +649,18 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 			i2c_dev->bus_clk_rate = be32_to_cpup(prop);
 	}
 
-	if (pdev->id == 3)
+#if defined(CONFIG_OF)
+	if (pdev->dev.of_node) {
+		const struct of_device_id *match;
+
+		match = of_match_device(tegra_i2c_of_match, &pdev->dev);
+		if (!match)
+			return -EINVAL;
+
+		i2c_dev->is_dvc = match->data;
+	}
+#endif
+	else if (pdev->id == 3)
 		i2c_dev->is_dvc = 1;
 	init_completion(&i2c_dev->msg_complete);
 
@@ -738,17 +762,6 @@ static int tegra_i2c_resume(struct platform_device *pdev)
 }
 #endif
 
-#if defined(CONFIG_OF)
-/* Match table for of_platform binding */
-static const struct of_device_id tegra_i2c_of_match[] __devinitconst = {
-	{ .compatible = "nvidia,tegra20-i2c", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
-#else
-#define tegra_i2c_of_match NULL
-#endif
-
 static struct platform_driver tegra_i2c_driver = {
 	.probe   = tegra_i2c_probe,
 	.remove  = tegra_i2c_remove,
-- 
1.7.5.4

[PATCH 2/3] arm/dt: tegra: Use new compatible value for DVC I2C controller

[Stephen Warren]

Update the device tree to indicate which I2C controller is the DVC
controller. AUXDATA needs to be updated too, since the compatible
value changed.

Signed-off-by: Stephen Warren <swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
It'd be best to apply this to the same tree as the previous patch. If
that doesn't happen, the DVC I2C driver won't be instantiated due to
the compatible value not being supported. In practice, this isn't an
issue though, since nothing uses the DVC I2C controller yet.

This relies on 0d4f747 "arm/tegra: convert tegra20 to GIC devicetree
binding" for context.

 arch/arm/boot/dts/tegra20.dtsi |    2 +-
 arch/arm/mach-tegra/board-dt.c |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/tegra20.dtsi b/arch/arm/boot/dts/tegra20.dtsi
index 660c8ad..3da7afd 100644
--- a/arch/arm/boot/dts/tegra20.dtsi
+++ b/arch/arm/boot/dts/tegra20.dtsi
@@ -39,7 +39,7 @@
 	i2c@7000d000 {
 		#address-cells = <1>;
 		#size-cells = <0>;
-		compatible = "nvidia,tegra20-i2c";
+		compatible = "nvidia,tegra20-i2c-dvc";
 		reg = <0x7000D000 0x200>;
 		interrupts = < 0 53 0x04 >;
 	};
diff --git a/arch/arm/mach-tegra/board-dt.c b/arch/arm/mach-tegra/board-dt.c
index b44633b..9abc89d 100644
--- a/arch/arm/mach-tegra/board-dt.c
+++ b/arch/arm/mach-tegra/board-dt.c
@@ -74,7 +74,7 @@ struct of_dev_auxdata tegra20_auxdata_lookup[] __initdata = {
 	OF_DEV_AUXDATA("nvidia,tegra20-i2c", TEGRA_I2C_BASE, "tegra-i2c.0", NULL),
 	OF_DEV_AUXDATA("nvidia,tegra20-i2c", TEGRA_I2C2_BASE, "tegra-i2c.1", NULL),
 	OF_DEV_AUXDATA("nvidia,tegra20-i2c", TEGRA_I2C3_BASE, "tegra-i2c.2", NULL),
-	OF_DEV_AUXDATA("nvidia,tegra20-i2c", TEGRA_DVC_BASE, "tegra-i2c.3", NULL),
+	OF_DEV_AUXDATA("nvidia,tegra20-i2c-dvc", TEGRA_DVC_BASE, "tegra-i2c.3", NULL),
 	OF_DEV_AUXDATA("nvidia,tegra20-i2s", TEGRA_I2S1_BASE, "tegra-i2s.0", NULL),
 	OF_DEV_AUXDATA("nvidia,tegra20-i2s", TEGRA_I2S2_BASE, "tegra-i2s.1", NULL),
 	OF_DEV_AUXDATA("nvidia,tegra20-das", TEGRA_APB_MISC_DAS_BASE, "tegra-das", NULL),
-- 
1.7.5.4

[PATCH 3/3] arm/dt: Add ADT7461 to Seaboard

[Stephen Warren]

The ADT7461 is a temperature monitoring IC. One is present on the DVC
I2C bus on Seaboard.

Signed-off-by: Stephen Warren <swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
For this to be useful, the previous two patches are required. Without
them, all the I2C transactions to this device will time out and spew
errors, but other device shouldn't be affected.

 arch/arm/boot/dts/tegra-seaboard.dts |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/arch/arm/boot/dts/tegra-seaboard.dts b/arch/arm/boot/dts/tegra-seaboard.dts
index 3cfbd04..b55a02e 100644
--- a/arch/arm/boot/dts/tegra-seaboard.dts
+++ b/arch/arm/boot/dts/tegra-seaboard.dts
@@ -25,6 +25,11 @@
 
 	i2c@7000d000 {
 		clock-frequency = <400000>;
+
+		adt7461@4c {
+			compatible = "adt7461";
+			reg = <0x4c>;
+		};
 	};
 
 	serial@70006000 {
-- 
1.7.5.4

Re: [PATCH 1/3] i2c: tegra: Support DVC controller in device tree

[Olof Johansson]

Hi,

On Sat, Dec 17, 2011 at 10:28:19PM -0700, Stephen Warren wrote:
> One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller)
> block. This block is identical to the rest of the I2C blocks, except that
> it only supports master mode, it has registers moved around, and it needs
> some extra init to get it into I2C mode.  The register moves are handled
> by i2c_readl and i2c_writel
> 
> This patch adds a new compatible value for controllers of this "DVC"
> type; I figured that this approach was reasonable, as opposed to adding
> an is-dvc property under the existing compatible value, since the HW
> truly is different.
> 
> Signed-off-by: Stephen Warren <swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> ---
> Ben, it'd probably be simplest if you could ack this patch, and we
> could take it through the Tegra tree.
> 
>  drivers/i2c/busses/i2c-tegra.c |   37 +++++++++++++++++++++++++------------
>  1 files changed, 25 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
> index 46b6500..c264e8c 100644
> --- a/drivers/i2c/busses/i2c-tegra.c
> +++ b/drivers/i2c/busses/i2c-tegra.c
> @@ -26,6 +26,7 @@
>  #include <linux/delay.h>
>  #include <linux/slab.h>
>  #include <linux/i2c-tegra.h>
> +#include <linux/of_device.h>
>  #include <linux/of_i2c.h>
>  #include <linux/module.h>
>  
> @@ -558,6 +559,18 @@ static const struct i2c_algorithm tegra_i2c_algo = {
>  	.functionality	= tegra_i2c_func,
>  };
>  
> +#if defined(CONFIG_OF)
> +/* Match table for of_platform binding */
> +static const struct of_device_id tegra_i2c_of_match[] __devinitconst = {
> +	{ .compatible = "nvidia,tegra20-i2c",     .data = (void *)0},
> +	{ .compatible = "nvidia,tegra20-i2c-dvc", .data = (void *)1},
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
> +#else
> +#define tegra_i2c_of_match NULL
> +#endif
> +
>  static int tegra_i2c_probe(struct platform_device *pdev)
>  {
>  	struct tegra_i2c_dev *i2c_dev;
> @@ -636,7 +649,18 @@ static int tegra_i2c_probe(struct platform_device *pdev)
>  			i2c_dev->bus_clk_rate = be32_to_cpup(prop);
>  	}
>  
> -	if (pdev->id == 3)
> +#if defined(CONFIG_OF)
> +	if (pdev->dev.of_node) {
> +		const struct of_device_id *match;
> +
> +		match = of_match_device(tegra_i2c_of_match, &pdev->dev);
> +		if (!match)
> +			return -EINVAL;
> +
> +		i2c_dev->is_dvc = match->data;

I would rather see a:

		i2c_dev->is_dvc = of_device_is_compatible(pdev->dev.of_node,
						"nvidia,tegra20-i2c-dvc");

...instead of passing a flag through the match data.


-Olof

Re: [PATCH 1/3] i2c: tegra: Support DVC controller in device tree

[Thierry Reding]

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* Stephen Warren wrote:
[...]
> @@ -636,7 +649,18 @@ static int tegra_i2c_probe(struct platform_device *pdev)
>  			i2c_dev->bus_clk_rate = be32_to_cpup(prop);
>  	}
>  
> -	if (pdev->id == 3)
> +#if defined(CONFIG_OF)
> +	if (pdev->dev.of_node) {
> +		const struct of_device_id *match;
> +
> +		match = of_match_device(tegra_i2c_of_match, &pdev->dev);
> +		if (!match)
> +			return -EINVAL;
> +
> +		i2c_dev->is_dvc = match->data;
> +	}
> +#endif
> +	else if (pdev->id == 3)

Shouldn't the "else" move into the CONFIG_OF branch?

Thierry

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Re: [PATCH 1/3] i2c: tegra: Support DVC controller in device tree

[Thierry Reding]

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* Thierry Reding wrote:
> * Stephen Warren wrote:
> [...]
> > @@ -636,7 +649,18 @@ static int tegra_i2c_probe(struct platform_device *pdev)
> >  			i2c_dev->bus_clk_rate = be32_to_cpup(prop);
> >  	}
> >  
> > -	if (pdev->id == 3)
> > +#if defined(CONFIG_OF)
> > +	if (pdev->dev.of_node) {
> > +		const struct of_device_id *match;
> > +
> > +		match = of_match_device(tegra_i2c_of_match, &pdev->dev);
> > +		if (!match)
> > +			return -EINVAL;
> > +
> > +		i2c_dev->is_dvc = match->data;
> > +	}
> > +#endif
> > +	else if (pdev->id == 3)
> 
> Shouldn't the "else" move into the CONFIG_OF branch?

Okay, I hadn't seen v2. Please ignore.

Thierry

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