[PATCH V3 0/3] add iwdg2 support for stm32mp157c

[PATCH V3 0/3] add iwdg2 support for stm32mp157c

[Ludovic Barre]

From: Ludovic Barre <ludovic.barre@st.com>

This patch series updates stm32_iwdg driver to manage config
by compatible. stm32mp1 config requires a pclk clock.

v3:
-remove stm32_iwdg_config structure, just assign the
 boolean directly to .dat

Ludovic Barre (3):
  watchdog: stm32: add pclk feature for stm32mp1
  ARM: dts: stm32: add iwdg2 support for stm32mp157c
  ARM: dts: stm32: add iwdg2 support for stm32mp157c-ed1

 .../devicetree/bindings/watchdog/st,stm32-iwdg.txt |  21 +++-
 arch/arm/boot/dts/stm32mp157c-ed1.dts              |   5 +
 arch/arm/boot/dts/stm32mp157c.dtsi                 |   8 ++
 drivers/watchdog/stm32_iwdg.c                      | 116 +++++++++++++--------
 4 files changed, 104 insertions(+), 46 deletions(-)

-- 
2.7.4

[PATCH V3 1/3] watchdog: stm32: add pclk feature for stm32mp1

[Ludovic Barre]

From: Ludovic Barre <ludovic.barre@st.com>

This patch adds config data to manage specific properties by
compatible. Adds stm32mp1 config which requires pclk clock.

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
---
 .../devicetree/bindings/watchdog/st,stm32-iwdg.txt |  21 +++-
 drivers/watchdog/stm32_iwdg.c                      | 116 +++++++++++++--------
 2 files changed, 91 insertions(+), 46 deletions(-)

diff --git a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
index cc13b10a..f07f6d89 100644
--- a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
+++ b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
@@ -2,18 +2,31 @@ STM32 Independent WatchDoG (IWDG)
 ---------------------------------
 
 Required properties:
-- compatible: "st,stm32-iwdg"
-- reg: physical base address and length of the registers set for the device
-- clocks: must contain a single entry describing the clock input
+- compatible: Should be either "st,stm32-iwdg" or "st,stm32mp1-iwdg"
+- reg: Physical base address and length of the registers set for the device
+- clocks: Reference to the clock entry lsi. Additional pclk clock entry
+  is required only for st,stm32mp1-iwdg.
+- clock-names: Name of the clocks used.
+  "lsi" for st,stm32-iwdg
+  "pclk", "lsi" for st,stm32mp1-iwdg
 
 Optional Properties:
 - timeout-sec: Watchdog timeout value in seconds.
 
-Example:
+Examples:
 
 iwdg: watchdog@40003000 {
 	compatible = "st,stm32-iwdg";
 	reg = <0x40003000 0x400>;
 	clocks = <&clk_lsi>;
+	clock-names = "lsi";
+	timeout-sec = <32>;
+};
+
+iwdg: iwdg@5a002000 {
+	compatible = "st,stm32mp1-iwdg";
+	reg = <0x5a002000 0x400>;
+	clocks = <&rcc IWDG2>, <&clk_lsi>;
+	clock-names = "pclk", "lsi";
 	timeout-sec = <32>;
 };
diff --git a/drivers/watchdog/stm32_iwdg.c b/drivers/watchdog/stm32_iwdg.c
index c97ad56..e00e3b3 100644
--- a/drivers/watchdog/stm32_iwdg.c
+++ b/drivers/watchdog/stm32_iwdg.c
@@ -11,12 +11,13 @@
 
 #include <linux/clk.h>
 #include <linux/delay.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/watchdog.h>
 
@@ -54,11 +55,15 @@
 #define TIMEOUT_US	100000
 #define SLEEP_US	1000
 
+#define HAS_PCLK	true
+
 struct stm32_iwdg {
 	struct watchdog_device	wdd;
 	void __iomem		*regs;
-	struct clk		*clk;
+	struct clk		*clk_lsi;
+	struct clk		*clk_pclk;
 	unsigned int		rate;
+	bool			has_pclk;
 };
 
 static inline u32 reg_read(void __iomem *base, u32 reg)
@@ -133,6 +138,44 @@ static int stm32_iwdg_set_timeout(struct watchdog_device *wdd,
 	return 0;
 }
 
+static int stm32_iwdg_clk_init(struct platform_device *pdev,
+			       struct stm32_iwdg *wdt)
+{
+	u32 ret;
+
+	wdt->clk_lsi = devm_clk_get(&pdev->dev, "lsi");
+	if (IS_ERR(wdt->clk_lsi)) {
+		dev_err(&pdev->dev, "Unable to get lsi clock\n");
+		return PTR_ERR(wdt->clk_lsi);
+	}
+
+	/* optional peripheral clock */
+	if (wdt->has_pclk) {
+		wdt->clk_pclk = devm_clk_get(&pdev->dev, "pclk");
+		if (IS_ERR(wdt->clk_pclk)) {
+			dev_err(&pdev->dev, "Unable to get pclk clock\n");
+			return PTR_ERR(wdt->clk_pclk);
+		}
+
+		ret = clk_prepare_enable(wdt->clk_pclk);
+		if (ret) {
+			dev_err(&pdev->dev, "Unable to prepare pclk clock\n");
+			return ret;
+		}
+	}
+
+	ret = clk_prepare_enable(wdt->clk_lsi);
+	if (ret) {
+		dev_err(&pdev->dev, "Unable to prepare lsi clock\n");
+		clk_disable_unprepare(wdt->clk_pclk);
+		return ret;
+	}
+
+	wdt->rate = clk_get_rate(wdt->clk_lsi);
+
+	return 0;
+}
+
 static const struct watchdog_info stm32_iwdg_info = {
 	.options	= WDIOF_SETTIMEOUT |
 			  WDIOF_MAGICCLOSE |
@@ -147,49 +190,42 @@ static const struct watchdog_ops stm32_iwdg_ops = {
 	.set_timeout	= stm32_iwdg_set_timeout,
 };
 
+static const struct of_device_id stm32_iwdg_of_match[] = {
+	{ .compatible = "st,stm32-iwdg", .data = (void *)!HAS_PCLK },
+	{ .compatible = "st,stm32mp1-iwdg", .data = (void *)HAS_PCLK },
+	{ /* end node */ }
+};
+MODULE_DEVICE_TABLE(of, stm32_iwdg_of_match);
+
 static int stm32_iwdg_probe(struct platform_device *pdev)
 {
 	struct watchdog_device *wdd;
+	const struct of_device_id *match;
 	struct stm32_iwdg *wdt;
 	struct resource *res;
-	void __iomem *regs;
-	struct clk *clk;
 	int ret;
 
+	match = of_match_device(stm32_iwdg_of_match, &pdev->dev);
+	if (!match)
+		return -ENODEV;
+
+	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
+	if (!wdt)
+		return -ENOMEM;
+
+	wdt->has_pclk = match->data;
+
 	/* This is the timer base. */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	regs = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(regs)) {
+	wdt->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(wdt->regs)) {
 		dev_err(&pdev->dev, "Could not get resource\n");
-		return PTR_ERR(regs);
+		return PTR_ERR(wdt->regs);
 	}
 
-	clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(clk)) {
-		dev_err(&pdev->dev, "Unable to get clock\n");
-		return PTR_ERR(clk);
-	}
-
-	ret = clk_prepare_enable(clk);
-	if (ret) {
-		dev_err(&pdev->dev, "Unable to prepare clock %p\n", clk);
+	ret = stm32_iwdg_clk_init(pdev, wdt);
+	if (ret)
 		return ret;
-	}
-
-	/*
-	 * Allocate our watchdog driver data, which has the
-	 * struct watchdog_device nested within it.
-	 */
-	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
-	if (!wdt) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
-	/* Initialize struct stm32_iwdg. */
-	wdt->regs = regs;
-	wdt->clk = clk;
-	wdt->rate = clk_get_rate(clk);
 
 	/* Initialize struct watchdog_device. */
 	wdd = &wdt->wdd;
@@ -217,7 +253,8 @@ static int stm32_iwdg_probe(struct platform_device *pdev)
 
 	return 0;
 err:
-	clk_disable_unprepare(clk);
+	clk_disable_unprepare(wdt->clk_lsi);
+	clk_disable_unprepare(wdt->clk_pclk);
 
 	return ret;
 }
@@ -227,23 +264,18 @@ static int stm32_iwdg_remove(struct platform_device *pdev)
 	struct stm32_iwdg *wdt = platform_get_drvdata(pdev);
 
 	watchdog_unregister_device(&wdt->wdd);
-	clk_disable_unprepare(wdt->clk);
+	clk_disable_unprepare(wdt->clk_lsi);
+	clk_disable_unprepare(wdt->clk_pclk);
 
 	return 0;
 }
 
-static const struct of_device_id stm32_iwdg_of_match[] = {
-	{ .compatible = "st,stm32-iwdg" },
-	{ /* end node */ }
-};
-MODULE_DEVICE_TABLE(of, stm32_iwdg_of_match);
-
 static struct platform_driver stm32_iwdg_driver = {
 	.probe		= stm32_iwdg_probe,
 	.remove		= stm32_iwdg_remove,
 	.driver = {
 		.name	= "iwdg",
-		.of_match_table = stm32_iwdg_of_match,
+		.of_match_table = of_match_ptr(stm32_iwdg_of_match),
 	},
 };
 module_platform_driver(stm32_iwdg_driver);
-- 
2.7.4

[PATCH V3 2/3] ARM: dts: stm32: add iwdg2 support for stm32mp157c

[Ludovic Barre]

From: Ludovic Barre <ludovic.barre@st.com>

This patch adds independent watchdog support for stm32mp157c.

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
---
 arch/arm/boot/dts/stm32mp157c.dtsi | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm/boot/dts/stm32mp157c.dtsi b/arch/arm/boot/dts/stm32mp157c.dtsi
index 7d17538..95cc166 100644
--- a/arch/arm/boot/dts/stm32mp157c.dtsi
+++ b/arch/arm/boot/dts/stm32mp157c.dtsi
@@ -784,6 +784,14 @@
 			status = "disabled";
 		};
 
+		iwdg2: watchdog@5a002000 {
+			compatible = "st,stm32mp1-iwdg";
+			reg = <0x5a002000 0x400>;
+			clocks = <&rcc IWDG2>, <&rcc CK_LSI>;
+			clock-names = "pclk", "lsi";
+			status = "disabled";
+		};
+
 		usbphyc: usbphyc@5a006000 {
 			#address-cells = <1>;
 			#size-cells = <0>;
-- 
2.7.4

[PATCH V3 3/3] ARM: dts: stm32: add iwdg2 support for stm32mp157c-ed1

[Ludovic Barre]

From: Ludovic Barre <ludovic.barre@st.com>

This patch activates independent watchdog support for
stm32mp157c board.

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
---
 arch/arm/boot/dts/stm32mp157c-ed1.dts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/stm32mp157c-ed1.dts b/arch/arm/boot/dts/stm32mp157c-ed1.dts
index ae33653..8af263a 100644
--- a/arch/arm/boot/dts/stm32mp157c-ed1.dts
+++ b/arch/arm/boot/dts/stm32mp157c-ed1.dts
@@ -68,6 +68,11 @@
 	status = "okay";
 };
 
+&iwdg2 {
+	timeout-sec = <32>;
+	status = "okay";
+};
+
 &uart4 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart4_pins_a>;
-- 
2.7.4

Re: [PATCH V3 1/3] watchdog: stm32: add pclk feature for stm32mp1

[Rob Herring]

On Wed, Jun 20, 2018 at 03:51:36PM +0200, Ludovic Barre wrote:
> From: Ludovic Barre <ludovic.barre@st.com>
> 
> This patch adds config data to manage specific properties by
> compatible. Adds stm32mp1 config which requires pclk clock.
> 
> Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
> ---
>  .../devicetree/bindings/watchdog/st,stm32-iwdg.txt |  21 +++-

Please split bindings to separate patch.

>  drivers/watchdog/stm32_iwdg.c                      | 116 +++++++++++++--------
>  2 files changed, 91 insertions(+), 46 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
> index cc13b10a..f07f6d89 100644
> --- a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
> +++ b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
> @@ -2,18 +2,31 @@ STM32 Independent WatchDoG (IWDG)
>  ---------------------------------
>  
>  Required properties:
> -- compatible: "st,stm32-iwdg"
> -- reg: physical base address and length of the registers set for the device
> -- clocks: must contain a single entry describing the clock input
> +- compatible: Should be either "st,stm32-iwdg" or "st,stm32mp1-iwdg"

Please format one per line.

> +- reg: Physical base address and length of the registers set for the device
> +- clocks: Reference to the clock entry lsi. Additional pclk clock entry
> +  is required only for st,stm32mp1-iwdg.
> +- clock-names: Name of the clocks used.
> +  "lsi" for st,stm32-iwdg
> +  "pclk", "lsi" for st,stm32mp1-iwdg

Put lsi 1st so it is always index 0.

>  
>  Optional Properties:
>  - timeout-sec: Watchdog timeout value in seconds.
>  
> -Example:
> +Examples:
>  
>  iwdg: watchdog@40003000 {
>  	compatible = "st,stm32-iwdg";
>  	reg = <0x40003000 0x400>;
>  	clocks = <&clk_lsi>;
> +	clock-names = "lsi";
> +	timeout-sec = <32>;
> +};
> +
> +iwdg: iwdg@5a002000 {

watchdog@...

Do we really need 2 example just to show 2 clocks?

> +	compatible = "st,stm32mp1-iwdg";
> +	reg = <0x5a002000 0x400>;
> +	clocks = <&rcc IWDG2>, <&clk_lsi>;
> +	clock-names = "pclk", "lsi";
>  	timeout-sec = <32>;
>  };

Re: [PATCH V3 1/3] watchdog: stm32: add pclk feature for stm32mp1

[Ludovic BARRE]

On 06/20/2018 09:14 PM, Rob Herring wrote:
> On Wed, Jun 20, 2018 at 03:51:36PM +0200, Ludovic Barre wrote:
>> From: Ludovic Barre <ludovic.barre@st.com>
>>
>> This patch adds config data to manage specific properties by
>> compatible. Adds stm32mp1 config which requires pclk clock.
>>
>> Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
>> ---
>>   .../devicetree/bindings/watchdog/st,stm32-iwdg.txt |  21 +++-
> 
> Please split bindings to separate patch.

OK

> 
>>   drivers/watchdog/stm32_iwdg.c                      | 116 +++++++++++++--------
>>   2 files changed, 91 insertions(+), 46 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
>> index cc13b10a..f07f6d89 100644
>> --- a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
>> +++ b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
>> @@ -2,18 +2,31 @@ STM32 Independent WatchDoG (IWDG)
>>   ---------------------------------
>>   
>>   Required properties:
>> -- compatible: "st,stm32-iwdg"
>> -- reg: physical base address and length of the registers set for the device
>> -- clocks: must contain a single entry describing the clock input
>> +- compatible: Should be either "st,stm32-iwdg" or "st,stm32mp1-iwdg"
> 
> Please format one per line.

OK

> 
>> +- reg: Physical base address and length of the registers set for the device
>> +- clocks: Reference to the clock entry lsi. Additional pclk clock entry
>> +  is required only for st,stm32mp1-iwdg.
>> +- clock-names: Name of the clocks used.
>> +  "lsi" for st,stm32-iwdg
>> +  "pclk", "lsi" for st,stm32mp1-iwdg
> 
> Put lsi 1st so it is always index 0.

OK

> 
>>   
>>   Optional Properties:
>>   - timeout-sec: Watchdog timeout value in seconds.
>>   
>> -Example:
>> +Examples:
>>   
>>   iwdg: watchdog@40003000 {
>>   	compatible = "st,stm32-iwdg";
>>   	reg = <0x40003000 0x400>;
>>   	clocks = <&clk_lsi>;
>> +	clock-names = "lsi";
>> +	timeout-sec = <32>;
>> +};
>> +
>> +iwdg: iwdg@5a002000 {
> 
> watchdog@...

sorry, I forget this occurrence.

> 
> Do we really need 2 example just to show 2 clocks?

No, I could keep only one

> 
>> +	compatible = "st,stm32mp1-iwdg";
>> +	reg = <0x5a002000 0x400>;
>> +	clocks = <&rcc IWDG2>, <&clk_lsi>;
>> +	clock-names = "pclk", "lsi";
>>   	timeout-sec = <32>;
>>   };