[PATCHv3 0/2] iio: adc: exynos_adc: Support Exynos3250 ADC

[PATCHv3 0/2] iio: adc: exynos_adc: Support Exynos3250 ADC

[Chanwoo Choi]

This patchset support Exynos3250 ADC (Analog Digital Converter) because
Exynos3250 has additional special clock for ADC IP.

Changes from v2:
- Check return value of clock function to deal with error exception
- Fix minor coding style to improve readability

Changes from v1:
- Add new "samsung,exynos-adc-v3" compatible to support Exynos3250 ADC
- Add a patch about DT binding documentation

Chanwoo Choi (2):
  iio: adc: exynos_adc: Control special clock of ADC to support Exynos3250 ADC
  iio: devicetree: Add DT binding documentation for Exynos3250 ADC

 .../devicetree/bindings/arm/samsung/exynos-adc.txt | 20 +++++
 drivers/iio/adc/exynos_adc.c                       | 86 ++++++++++++++++++----
 2 files changed, 93 insertions(+), 13 deletions(-)

-- 
1.8.0

[PATCHv3 1/2] iio: adc: exynos_adc: Control special clock of ADC to support Exynos3250 ADC

[Chanwoo Choi]

This patch control special clock for ADC in Exynos series's FSYS block.
If special clock of ADC is registerd on clock list of common clk framework,
Exynos ADC drvier have to control this clock.

Exynos3250/Exynos4/Exynos5 has 'adc' clock as following:
- 'adc' clock: bus clock for ADC

Exynos3250 has additional 'sclk_tsadc' clock as following:
- 'sclk_tsadc' clock: special clock for ADC which provide clock to internal ADC

Exynos 4210/4212/4412 and Exynos5250/5420 has not included 'sclk_tsadc' clock
in FSYS_BLK. But, Exynos3250 based on Cortex-A7 has only included 'sclk_tsadc'
clock in FSYS_BLK.

Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Naveen Krishna Chatradhi
Cc: linux-iio@vger.kernel.org
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 drivers/iio/adc/exynos_adc.c | 86 +++++++++++++++++++++++++++++++++++++-------
 1 file changed, 73 insertions(+), 13 deletions(-)

diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
index d25b262..486771e 100644
--- a/drivers/iio/adc/exynos_adc.c
+++ b/drivers/iio/adc/exynos_adc.c
@@ -40,8 +40,9 @@
 #include <linux/iio/driver.h>
 
 enum adc_version {
-	ADC_V1,
-	ADC_V2
+	ADC_V1 = 0x1,
+	ADC_V2 = 0x2,
+	ADC_V3 = (ADC_V1 | ADC_V2),
 };
 
 /* EXYNOS4412/5250 ADC_V1 registers definitions */
@@ -85,9 +86,11 @@ enum adc_version {
 #define EXYNOS_ADC_TIMEOUT	(msecs_to_jiffies(1000))
 
 struct exynos_adc {
+	struct device		*dev;
 	void __iomem		*regs;
 	void __iomem		*enable_reg;
 	struct clk		*clk;
+	struct clk		*sclk;
 	unsigned int		irq;
 	struct regulator	*vdd;
 
@@ -100,6 +103,7 @@ struct exynos_adc {
 static const struct of_device_id exynos_adc_match[] = {
 	{ .compatible = "samsung,exynos-adc-v1", .data = (void *)ADC_V1 },
 	{ .compatible = "samsung,exynos-adc-v2", .data = (void *)ADC_V2 },
+	{ .compatible = "samsung,exynos-adc-v3", .data = (void *)ADC_V3 },
 	{},
 };
 MODULE_DEVICE_TABLE(of, exynos_adc_match);
@@ -128,7 +132,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
 	mutex_lock(&indio_dev->mlock);
 
 	/* Select the channel to be used and Trigger conversion */
-	if (info->version == ADC_V2) {
+	if (info->version >= ADC_V2) {
 		con2 = readl(ADC_V2_CON2(info->regs));
 		con2 &= ~ADC_V2_CON2_ACH_MASK;
 		con2 |= ADC_V2_CON2_ACH_SEL(chan->address);
@@ -165,7 +169,7 @@ static irqreturn_t exynos_adc_isr(int irq, void *dev_id)
 	info->value = readl(ADC_V1_DATX(info->regs)) &
 						ADC_DATX_MASK;
 	/* clear irq */
-	if (info->version == ADC_V2)
+	if (info->version >= ADC_V2)
 		writel(1, ADC_V2_INT_ST(info->regs));
 	else
 		writel(1, ADC_V1_INTCLR(info->regs));
@@ -226,11 +230,43 @@ static int exynos_adc_remove_devices(struct device *dev, void *c)
 	return 0;
 }
 
+static int exynos_adc_enable_clock(struct exynos_adc *info, bool enable)
+{
+	int ret;
+
+	if (enable) {
+		ret = clk_prepare_enable(info->clk);
+		if (ret) {
+			dev_err(info->dev, "failed to enable adc clock\n");
+			return ret;
+		}
+		if (info->version == ADC_V3) {
+			ret = clk_prepare_enable(info->sclk);
+			if (ret) {
+				dev_err(info->dev,
+					"failed to enable sclk_tsadc clock\n");
+				goto err;
+			}
+		}
+
+	} else {
+		if (info->version == ADC_V3)
+			clk_disable_unprepare(info->sclk);
+		clk_disable_unprepare(info->clk);
+	}
+
+	return 0;
+err:
+	clk_disable_unprepare(info->clk);
+
+	return ret;
+}
+
 static void exynos_adc_hw_init(struct exynos_adc *info)
 {
 	u32 con1, con2;
 
-	if (info->version == ADC_V2) {
+	if (info->version >= ADC_V2) {
 		con1 = ADC_V2_CON1_SOFT_RESET;
 		writel(con1, ADC_V2_CON1(info->regs));
 
@@ -287,6 +323,7 @@ static int exynos_adc_probe(struct platform_device *pdev)
 	}
 
 	info->irq = irq;
+	info->dev = &pdev->dev;
 
 	init_completion(&info->completion);
 
@@ -300,6 +337,8 @@ static int exynos_adc_probe(struct platform_device *pdev)
 
 	writel(1, info->enable_reg);
 
+	info->version = exynos_adc_get_version(pdev);
+
 	info->clk = devm_clk_get(&pdev->dev, "adc");
 	if (IS_ERR(info->clk)) {
 		dev_err(&pdev->dev, "failed getting clock, err = %ld\n",
@@ -308,6 +347,16 @@ static int exynos_adc_probe(struct platform_device *pdev)
 		goto err_irq;
 	}
 
+	if (info->version == ADC_V3) {
+		info->sclk = devm_clk_get(&pdev->dev, "sclk_tsadc");
+		if (IS_ERR(info->sclk)) {
+			ret = PTR_ERR(info->sclk);
+			dev_warn(&pdev->dev,
+				"failed getting sclk clock, err = %d\n", ret);
+			goto err_irq;
+		}
+	}
+
 	info->vdd = devm_regulator_get(&pdev->dev, "vdd");
 	if (IS_ERR(info->vdd)) {
 		dev_err(&pdev->dev, "failed getting regulator, err = %ld\n",
@@ -316,8 +365,6 @@ static int exynos_adc_probe(struct platform_device *pdev)
 		goto err_irq;
 	}
 
-	info->version = exynos_adc_get_version(pdev);
-
 	platform_set_drvdata(pdev, indio_dev);
 
 	indio_dev->name = dev_name(&pdev->dev);
@@ -340,7 +387,11 @@ static int exynos_adc_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_iio_dev;
 
-	clk_prepare_enable(info->clk);
+	ret = exynos_adc_enable_clock(info, true);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable clock\n");
+		goto err_regulator;
+	}
 
 	exynos_adc_hw_init(info);
 
@@ -355,8 +406,9 @@ static int exynos_adc_probe(struct platform_device *pdev)
 err_of_populate:
 	device_for_each_child(&pdev->dev, NULL,
 				exynos_adc_remove_devices);
+	exynos_adc_enable_clock(info, false);
+err_regulator:
 	regulator_disable(info->vdd);
-	clk_disable_unprepare(info->clk);
 err_iio_dev:
 	iio_device_unregister(indio_dev);
 err_irq:
@@ -372,7 +424,7 @@ static int exynos_adc_remove(struct platform_device *pdev)
 	device_for_each_child(&pdev->dev, NULL,
 				exynos_adc_remove_devices);
 	regulator_disable(info->vdd);
-	clk_disable_unprepare(info->clk);
+	exynos_adc_enable_clock(info, false);
 	writel(0, info->enable_reg);
 	iio_device_unregister(indio_dev);
 	free_irq(info->irq, info);
@@ -387,7 +439,7 @@ static int exynos_adc_suspend(struct device *dev)
 	struct exynos_adc *info = iio_priv(indio_dev);
 	u32 con;
 
-	if (info->version == ADC_V2) {
+	if (info->version >= ADC_V2) {
 		con = readl(ADC_V2_CON1(info->regs));
 		con &= ~ADC_CON_EN_START;
 		writel(con, ADC_V2_CON1(info->regs));
@@ -397,7 +449,7 @@ static int exynos_adc_suspend(struct device *dev)
 		writel(con, ADC_V1_CON(info->regs));
 	}
 
-	clk_disable_unprepare(info->clk);
+	exynos_adc_enable_clock(info, false);
 	writel(0, info->enable_reg);
 	regulator_disable(info->vdd);
 
@@ -415,11 +467,19 @@ static int exynos_adc_resume(struct device *dev)
 		return ret;
 
 	writel(1, info->enable_reg);
-	clk_prepare_enable(info->clk);
+	ret = exynos_adc_enable_clock(info, true);
+	if (ret) {
+		dev_err(dev, "failed to enable clock\n");
+		goto err;
+	}
 
 	exynos_adc_hw_init(info);
 
 	return 0;
+err:
+	regulator_disable(info->vdd);
+
+	return ret;
 }
 #endif
 
-- 
1.8.0

[PATCHv3 2/2] iio: devicetree: Add DT binding documentation for Exynos3250 ADC

[Chanwoo Choi]

This patch add DT binding documentation for Exynos3250 ADC IP. Exynos3250 has
special clock ('sclk_tsadc') for ADC which provide clock to internal ADC.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 .../devicetree/bindings/arm/samsung/exynos-adc.txt   | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
index 5d49f2b..7532ec3 100644
--- a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
+++ b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
@@ -14,6 +14,8 @@ Required properties:
 				for exynos4412/5250 controllers.
 			Must be "samsung,exynos-adc-v2" for
 				future controllers.
+			Must be "samsung,exynos-adc-v3" for
+				for exynos3250 controllers.
 - reg:			Contains ADC register address range (base address and
 			length) and the address of the phy enable register.
 - interrupts: 		Contains the interrupt information for the timer. The
@@ -21,7 +23,11 @@ Required properties:
 			the Samsung device uses.
 - #io-channel-cells = <1>; As ADC has multiple outputs
 - clocks		From common clock binding: handle to adc clock.
+			From common clock binding: handle to sclk_tsadc clock
+			if using Exynos3250.
 - clock-names		From common clock binding: Shall be "adc".
+			From common clock binding: Shall be "sclk_tsadc"
+			if using Exynos3250.
 - vdd-supply		VDD input supply.
 
 Note: child nodes can be added for auto probing from device tree.
@@ -41,6 +47,20 @@ adc: adc@12D10000 {
 	vdd-supply = <&buck5_reg>;
 };
 
+If Exynos3250 uses ADC,
+adc: adc@126C0000 {
+	compatible = "samsung,exynos-adc-v3";
+	reg = <0x126C0000 0x100>, <0x10020718 0x4>;
+	interrupts = <0 137 0>;
+	#io-channel-cells = <1>;
+	io-channel-ranges;
+
+	clock-names = "adc", "sclk_tsadc";
+	clocks = <&cmu CLK_TSADC>, <&cmu CLK_SCLK_TSADC>;
+
+	vdd-supply = <&buck5_reg>;
+};
+
 
 Example: Adding child nodes in dts file
 
-- 
1.8.0

Re: [PATCHv3 1/2] iio: adc: exynos_adc: Control special clock of ADC to support Exynos3250 ADC

[Tomasz Figa]

Hi Chanwoo,

On 16.04.2014 12:11, Chanwoo Choi wrote:
> This patch control special clock for ADC in Exynos series's FSYS block.
> If special clock of ADC is registerd on clock list of common clk framework,
> Exynos ADC drvier have to control this clock.
>
> Exynos3250/Exynos4/Exynos5 has 'adc' clock as following:
> - 'adc' clock: bus clock for ADC
>
> Exynos3250 has additional 'sclk_tsadc' clock as following:
> - 'sclk_tsadc' clock: special clock for ADC which provide clock to internal ADC
>
> Exynos 4210/4212/4412 and Exynos5250/5420 has not included 'sclk_tsadc' clock
> in FSYS_BLK. But, Exynos3250 based on Cortex-A7 has only included 'sclk_tsadc'
> clock in FSYS_BLK.
>
> Cc: Jonathan Cameron <jic23@kernel.org>
> Cc: Kukjin Kim <kgene.kim@samsung.com>
> Cc: Naveen Krishna Chatradhi
> Cc: linux-iio@vger.kernel.org
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> ---
>   drivers/iio/adc/exynos_adc.c | 86 +++++++++++++++++++++++++++++++++++++-------
>   1 file changed, 73 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
> index d25b262..486771e 100644
> --- a/drivers/iio/adc/exynos_adc.c
> +++ b/drivers/iio/adc/exynos_adc.c
> @@ -40,8 +40,9 @@
>   #include <linux/iio/driver.h>
>
>   enum adc_version {
> -	ADC_V1,
> -	ADC_V2
> +	ADC_V1 = 0x1,
> +	ADC_V2 = 0x2,
> +	ADC_V3 = (ADC_V1 | ADC_V2),

I don't think Exynos3250 has really a V3 of the ADC block. It looks like 
a V2, just with different integration details. This approach is 
confusing and will create problems if real V3 shows up.

In general, using a version enum and a lot of ifs for particular 
versions in the code is rather a bad practice, especially when multiple 
versions happen to require the same quirks.

Instead, a variant struct should be introduced with bitfields for 
particular quirks and/or register offsets and/or function pointers. Let 
me show example solutions inline with your changes below.

>   };
>
>   /* EXYNOS4412/5250 ADC_V1 registers definitions */
> @@ -85,9 +86,11 @@ enum adc_version {
>   #define EXYNOS_ADC_TIMEOUT	(msecs_to_jiffies(1000))
>
>   struct exynos_adc {
> +	struct device		*dev;
>   	void __iomem		*regs;
>   	void __iomem		*enable_reg;
>   	struct clk		*clk;
> +	struct clk		*sclk;
>   	unsigned int		irq;
>   	struct regulator	*vdd;
>
> @@ -100,6 +103,7 @@ struct exynos_adc {
>   static const struct of_device_id exynos_adc_match[] = {
>   	{ .compatible = "samsung,exynos-adc-v1", .data = (void *)ADC_V1 },
>   	{ .compatible = "samsung,exynos-adc-v2", .data = (void *)ADC_V2 },
> +	{ .compatible = "samsung,exynos-adc-v3", .data = (void *)ADC_V3 },
>   	{},
>   };
>   MODULE_DEVICE_TABLE(of, exynos_adc_match);
> @@ -128,7 +132,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
>   	mutex_lock(&indio_dev->mlock);
>
>   	/* Select the channel to be used and Trigger conversion */
> -	if (info->version == ADC_V2) {
> +	if (info->version >= ADC_V2) {
>   		con2 = readl(ADC_V2_CON2(info->regs));
>   		con2 &= ~ADC_V2_CON2_ACH_MASK;
>   		con2 |= ADC_V2_CON2_ACH_SEL(chan->address);

This function should be split into exynos_adc_v1_read_raw() and 
exynos_adc_v2_read_raw(). Then a function pointer for int 
(*read_raw)(...) should be added to the variant struct I mentioned 
above. Then the generic part of existing exynos_read_raw() would just 
call variant->read_raw().

> @@ -165,7 +169,7 @@ static irqreturn_t exynos_adc_isr(int irq, void *dev_id)
>   	info->value = readl(ADC_V1_DATX(info->regs)) &
>   						ADC_DATX_MASK;
>   	/* clear irq */
> -	if (info->version == ADC_V2)
> +	if (info->version >= ADC_V2)
>   		writel(1, ADC_V2_INT_ST(info->regs));
>   	else
>   		writel(1, ADC_V1_INTCLR(info->regs));

void (*clear_irq)().

> @@ -226,11 +230,43 @@ static int exynos_adc_remove_devices(struct device *dev, void *c)
>   	return 0;
>   }
>
> +static int exynos_adc_enable_clock(struct exynos_adc *info, bool enable)
> +{
> +	int ret;
> +
> +	if (enable) {
> +		ret = clk_prepare_enable(info->clk);
> +		if (ret) {
> +			dev_err(info->dev, "failed to enable adc clock\n");
> +			return ret;
> +		}
> +		if (info->version == ADC_V3) {

Here, a bitfield bool needs_sclk:1; in the variant struct would be 
sufficient.

> +			ret = clk_prepare_enable(info->sclk);
> +			if (ret) {
> +				dev_err(info->dev,
> +					"failed to enable sclk_tsadc clock\n");
> +				goto err;
> +			}
> +		}
> +
> +	} else {
> +		if (info->version == ADC_V3)
> +			clk_disable_unprepare(info->sclk);
> +		clk_disable_unprepare(info->clk);
> +	}
> +
> +	return 0;
> +err:
> +	clk_disable_unprepare(info->clk);
> +
> +	return ret;
> +}

Ugh. Please split this into exynos_adc_enable_clock() and 
exynos_adc_disable_clock().

> +
>   static void exynos_adc_hw_init(struct exynos_adc *info)
>   {
>   	u32 con1, con2;
>
> -	if (info->version == ADC_V2) {
> +	if (info->version >= ADC_V2) {
>   		con1 = ADC_V2_CON1_SOFT_RESET;
>   		writel(con1, ADC_V2_CON1(info->regs));
>

This function should be completely split into v1_hw_init() and 
v2_hw_init() and the code calling currently exynos_adc_hw_init() could 
call variant->hw_init() directly.

> @@ -287,6 +323,7 @@ static int exynos_adc_probe(struct platform_device *pdev)
>   	}
>
>   	info->irq = irq;
> +	info->dev = &pdev->dev;
>
>   	init_completion(&info->completion);
>
> @@ -300,6 +337,8 @@ static int exynos_adc_probe(struct platform_device *pdev)
>
>   	writel(1, info->enable_reg);
>
> +	info->version = exynos_adc_get_version(pdev);
> +

Instead of getting version, here a pointer to variant struct could be 
retrieved.

>   	info->clk = devm_clk_get(&pdev->dev, "adc");
>   	if (IS_ERR(info->clk)) {
>   		dev_err(&pdev->dev, "failed getting clock, err = %ld\n",
> @@ -308,6 +347,16 @@ static int exynos_adc_probe(struct platform_device *pdev)
>   		goto err_irq;
>   	}
>
> +	if (info->version == ADC_V3) {

if (info->variant->needs_sclk) {

> +		info->sclk = devm_clk_get(&pdev->dev, "sclk_tsadc");
> +		if (IS_ERR(info->sclk)) {
> +			ret = PTR_ERR(info->sclk);
> +			dev_warn(&pdev->dev,
> +				"failed getting sclk clock, err = %d\n", ret);
> +			goto err_irq;
> +		}
> +	}
> +

etc., etc.

Best regards,
Tomasz

Re: [PATCHv3 2/2] iio: devicetree: Add DT binding documentation for Exynos3250 ADC

[Tomasz Figa]

Hi Chanwoo,

On 16.04.2014 12:11, Chanwoo Choi wrote:
> This patch add DT binding documentation for Exynos3250 ADC IP. Exynos3250 has
> special clock ('sclk_tsadc') for ADC which provide clock to internal ADC.
>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Pawel Moll <pawel.moll@arm.com>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
> Cc: Kumar Gala <galak@codeaurora.org>
> Cc: Randy Dunlap <rdunlap@infradead.org>
> Cc: Kukjin Kim <kgene.kim@samsung.com>
> Cc: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
> Cc: Tomasz Figa <t.figa@samsung.com>
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> ---
>   .../devicetree/bindings/arm/samsung/exynos-adc.txt   | 20 ++++++++++++++++++++
>   1 file changed, 20 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
> index 5d49f2b..7532ec3 100644
> --- a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
> +++ b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
> @@ -14,6 +14,8 @@ Required properties:
>   				for exynos4412/5250 controllers.
>   			Must be "samsung,exynos-adc-v2" for
>   				future controllers.
> +			Must be "samsung,exynos-adc-v3" for
> +				for exynos3250 controllers.

I don't think adc-v3 is correct here. It looks like a normal V2 with 
additional special clock input. Possibly "samsung,exynos3250-adc-v2" or 
"samsung,exynos-adc-v2-sclk" would be better choices.

>   - reg:			Contains ADC register address range (base address and
>   			length) and the address of the phy enable register.
>   - interrupts: 		Contains the interrupt information for the timer. The
> @@ -21,7 +23,11 @@ Required properties:
>   			the Samsung device uses.
>   - #io-channel-cells = <1>; As ADC has multiple outputs
>   - clocks		From common clock binding: handle to adc clock.
> +			From common clock binding: handle to sclk_tsadc clock
> +			if using Exynos3250.
>   - clock-names		From common clock binding: Shall be "adc".
> +			From common clock binding: Shall be "sclk_tsadc"
> +			if using Exynos3250.
>   - vdd-supply		VDD input supply.
>
>   Note: child nodes can be added for auto probing from device tree.
> @@ -41,6 +47,20 @@ adc: adc@12D10000 {
>   	vdd-supply = <&buck5_reg>;
>   };
>
> +If Exynos3250 uses ADC,

Please keep proper formatting:

Example: Node for ADC of Exynos3250 with additional special clock

Best regards,
Tomasz

Re: [PATCHv3 2/2] iio: devicetree: Add DT binding documentation for Exynos3250 ADC

[Chanwoo Choi]

Hi Tomasz,

On 04/16/2014 08:49 PM, Tomasz Figa wrote:
> Hi Chanwoo,
> 
> On 16.04.2014 12:11, Chanwoo Choi wrote:
>> This patch add DT binding documentation for Exynos3250 ADC IP. Exynos3250 has
>> special clock ('sclk_tsadc') for ADC which provide clock to internal ADC.
>>
>> Cc: Rob Herring <robh+dt@kernel.org>
>> Cc: Pawel Moll <pawel.moll@arm.com>
>> Cc: Mark Rutland <mark.rutland@arm.com>
>> Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
>> Cc: Kumar Gala <galak@codeaurora.org>
>> Cc: Randy Dunlap <rdunlap@infradead.org>
>> Cc: Kukjin Kim <kgene.kim@samsung.com>
>> Cc: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
>> Cc: Tomasz Figa <t.figa@samsung.com>
>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
>> ---
>>   .../devicetree/bindings/arm/samsung/exynos-adc.txt   | 20 ++++++++++++++++++++
>>   1 file changed, 20 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
>> index 5d49f2b..7532ec3 100644
>> --- a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
>> +++ b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
>> @@ -14,6 +14,8 @@ Required properties:
>>                   for exynos4412/5250 controllers.
>>               Must be "samsung,exynos-adc-v2" for
>>                   future controllers.
>> +            Must be "samsung,exynos-adc-v3" for
>> +                for exynos3250 controllers.
> 
> I don't think adc-v3 is correct here. It looks like a normal V2 with additional special clock input. Possibly "samsung,exynos3250-adc-v2" or "samsung,exynos-adc-v2-sclk" would be better choices.

OK, I'll fix it with following compatible
- "samsung,exynos-adc-v2-sclk"

> 
>>   - reg:            Contains ADC register address range (base address and
>>               length) and the address of the phy enable register.
>>   - interrupts:         Contains the interrupt information for the timer. The
>> @@ -21,7 +23,11 @@ Required properties:
>>               the Samsung device uses.
>>   - #io-channel-cells = <1>; As ADC has multiple outputs
>>   - clocks        From common clock binding: handle to adc clock.
>> +            From common clock binding: handle to sclk_tsadc clock
>> +            if using Exynos3250.
>>   - clock-names        From common clock binding: Shall be "adc".
>> +            From common clock binding: Shall be "sclk_tsadc"
>> +            if using Exynos3250.
>>   - vdd-supply        VDD input supply.
>>
>>   Note: child nodes can be added for auto probing from device tree.
>> @@ -41,6 +47,20 @@ adc: adc@12D10000 {
>>       vdd-supply = <&buck5_reg>;
>>   };
>>
>> +If Exynos3250 uses ADC,
> 
> Please keep proper formatting:
> 
> Example: Node for ADC of Exynos3250 with additional special clock

Thanks, I'll fix it.

Best regards,
Chanwoo Choi