[PATCH v7 0/2] Add watchdog driver for Sunplus SP7021 SoC

[PATCH v7 0/2] Add watchdog driver for Sunplus SP7021 SoC

[Xiantao Hu]

This is a patch series for watchdog driver for Sunplus SP7021 SoC.

Sunplus SP7021 is an ARM Cortex A7 (4 cores) based SoC. It integrates
many peripherals (ex: UART, I2C, SPI, SDIO, eMMC, USB, SD card and
etc.) into a single chip. It is designed for industrial control.

Refer to:
https://sunplus-tibbo.atlassian.net/wiki/spaces/doc/overview
https://tibbo.com/store/plus1.html

Xiantao Hu (2):
  dt-bindings: watchdog: Add watchdog yaml file for Sunplus SP7021
  watchdog: Add watchdog driver for Sunplus SP7021

 .../bindings/watchdog/sunplus,sp7021-wdt.yaml |  47 ++++
 MAINTAINERS                                   |   7 +
 drivers/watchdog/Kconfig                      |  11 +
 drivers/watchdog/Makefile                     |   1 +
 drivers/watchdog/sunplus_wdt.c                | 220 ++++++++++++++++++
 5 files changed, 286 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
 create mode 100644 drivers/watchdog/sunplus_wdt.c

-- 
2.33.1

[PATCH v7 1/2] dt-bindings: watchdog: Add watchdog yaml file for Sunplus SP7021

[Xiantao Hu]

This adds the documentation for the devicetree bindings of the Sunplus
SP7021 watchdog driver, found from SP7021 SoCs and newer.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Xiantao Hu <xt.hu@cqplus1.com>
---
 .../bindings/watchdog/sunplus,sp7021-wdt.yaml | 47 +++++++++++++++++++
 MAINTAINERS                                   |  6 +++
 2 files changed, 53 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml

diff --git a/Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml b/Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
new file mode 100644
index 000000000..9a9bfe150
--- /dev/null
+++ b/Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
@@ -0,0 +1,47 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) Sunplus Co., Ltd. 2021
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/watchdog/sunplus,sp7021-wdt.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Sunplus SoCs Watchdog Device Tree Bindings
+
+maintainers:
+  - XianTao Hu <xt.hu@cqplus1.com>
+
+allOf:
+  - $ref: watchdog.yaml#
+
+properties:
+  compatible:
+    const: sunplus,sp7021-wdt
+
+  reg:
+    items:
+      - description: watchdog registers regions
+      - description: miscellaneous control registers regions
+
+  clocks:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - resets
+
+additionalProperties: false
+
+examples:
+  - |
+    watchdog: watchdog@9c000630 {
+        compatible = "sunplus,sp7021-wdt";
+        reg = <0x9c000630 0x08>, <0x9C000274 0x04>;
+        clocks = <&clkc 0x24>;
+        resets = <&rstc 0x14>;
+    };
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index fb18ce716..fe6cc971c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -18242,6 +18242,12 @@ L:	netdev@vger.kernel.org
 S:	Maintained
 F:	drivers/net/ethernet/dlink/sundance.c
 
+SUNPLUS WATCHDOG DRIVER
+M:	Xiantao Hu <xt.hu@cqplus1.com>
+L:	linux-watchdog@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
+
 SUPERH
 M:	Yoshinori Sato <ysato@users.sourceforge.jp>
 M:	Rich Felker <dalias@libc.org>
-- 
2.33.1

[PATCH v7 2/2] watchdog: Add watchdog driver for Sunplus SP7021

[Xiantao Hu]

Sunplus SP7021 requires watchdog timer support.
Add watchdog driver to enable this.

Signed-off-by: Xiantao Hu <xt.hu@cqplus1.com>
---
Changes in v7:
 - Addressed all comments from Mr. Guenter Roeck.
   Fix sp_wdt_ping() and add comment to explain the calculation.

 MAINTAINERS                    |   1 +
 drivers/watchdog/Kconfig       |  11 ++
 drivers/watchdog/Makefile      |   1 +
 drivers/watchdog/sunplus_wdt.c | 220 +++++++++++++++++++++++++++++++++
 4 files changed, 233 insertions(+)
 create mode 100644 drivers/watchdog/sunplus_wdt.c

diff --git a/MAINTAINERS b/MAINTAINERS
index fe6cc971c..a1b3d76e2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -18247,6 +18247,7 @@ M:	Xiantao Hu <xt.hu@cqplus1.com>
 L:	linux-watchdog@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
+F:	drivers/watchdog/sunplus_wdt.c
 
 SUPERH
 M:	Yoshinori Sato <ysato@users.sourceforge.jp>
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 9d222ba17..d3dbe8695 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -976,6 +976,17 @@ config MSC313E_WATCHDOG
 	  To compile this driver as a module, choose M here: the
 	  module will be called msc313e_wdt.
 
+config SUNPLUS_WATCHDOG
+	tristate "Sunplus watchdog support"
+	depends on ARCH_SUNPLUS || COMPILE_TEST
+	select WATCHDOG_CORE
+	help
+	  Say Y here to include support for the watchdog timer
+	  in Sunplus SoCs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called sunplus_wdt.
+
 # X86 (i386 + ia64 + x86_64) Architecture
 
 config ACQUIRE_WDT
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 2ee970641..0fa548ee6 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -93,6 +93,7 @@ obj-$(CONFIG_PM8916_WATCHDOG) += pm8916_wdt.o
 obj-$(CONFIG_ARM_SMC_WATCHDOG) += arm_smc_wdt.o
 obj-$(CONFIG_VISCONTI_WATCHDOG) += visconti_wdt.o
 obj-$(CONFIG_MSC313E_WATCHDOG) += msc313e_wdt.o
+obj-$(CONFIG_SUNPLUS_WATCHDOG) += sunplus_wdt.o
 
 # X86 (i386 + ia64 + x86_64) Architecture
 obj-$(CONFIG_ACQUIRE_WDT) += acquirewdt.o
diff --git a/drivers/watchdog/sunplus_wdt.c b/drivers/watchdog/sunplus_wdt.c
new file mode 100644
index 000000000..e2d8c532b
--- /dev/null
+++ b/drivers/watchdog/sunplus_wdt.c
@@ -0,0 +1,220 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * sunplus Watchdog Driver
+ *
+ * Copyright (C) 2021 Sunplus Technology Co., Ltd.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/watchdog.h>
+
+#define WDT_CTRL		0x00
+#define WDT_CNT			0x04
+
+#define WDT_STOP		0x3877
+#define WDT_RESUME		0x4A4B
+#define WDT_CLRIRQ		0x7482
+#define WDT_UNLOCK		0xAB00
+#define WDT_LOCK		0xAB01
+#define WDT_CONMAX		0xDEAF
+
+/* TIMEOUT_MAX = ffff0/90kHz =11.65, so longer than 11 seconds will time out. */
+#define SP_WDT_MAX_TIMEOUT	11U
+#define SP_WDT_DEFAULT_TIMEOUT	10
+
+#define STC_CLK			90000
+
+#define DEVICE_NAME		"sunplus-wdt"
+
+static unsigned int timeout;
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds");
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+			__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+struct sp_wdt_priv {
+	struct watchdog_device wdev;
+	void __iomem *base;
+	struct clk *clk;
+	struct reset_control *rstc;
+};
+
+static int sp_wdt_restart(struct watchdog_device *wdev,
+			  unsigned long action, void *data)
+{
+	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
+	void __iomem *base = priv->base;
+
+	writel(WDT_STOP, base + WDT_CTRL);
+	writel(WDT_UNLOCK, base + WDT_CTRL);
+	writel(0x0001, base + WDT_CNT);
+	writel(WDT_LOCK, base + WDT_CTRL);
+	writel(WDT_RESUME, base + WDT_CTRL);
+
+	return 0;
+}
+
+static int sp_wdt_ping(struct watchdog_device *wdev)
+{
+	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
+	void __iomem *base = priv->base;
+	u32 count;
+
+	if (wdev->timeout > SP_WDT_MAX_TIMEOUT) {
+		/* WDT_CONMAX sets the count to the maximum (down-counting). */
+		writel(WDT_CONMAX, base + WDT_CTRL);
+	} else {
+		writel(WDT_UNLOCK, base + WDT_CTRL);
+		/*
+		 * Watchdog timer is a 20-bit down-counting based on STC_CLK.
+		 * This register bits[16:0] is from bit[19:4] of the watchdog
+		 * timer counter.
+		 */
+		count = (wdev->timeout * STC_CLK) >> 4;
+		writel(count, base + WDT_CNT);
+		writel(WDT_LOCK, base + WDT_CTRL);
+	}
+
+	return 0;
+}
+
+static int sp_wdt_stop(struct watchdog_device *wdev)
+{
+	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
+	void __iomem *base = priv->base;
+
+	writel(WDT_STOP, base + WDT_CTRL);
+
+	return 0;
+}
+
+static int sp_wdt_start(struct watchdog_device *wdev)
+{
+	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
+	void __iomem *base = priv->base;
+
+	writel(WDT_RESUME, base + WDT_CTRL);
+
+	return 0;
+}
+
+static unsigned int sp_wdt_get_timeleft(struct watchdog_device *wdev)
+{
+	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
+	void __iomem *base = priv->base;
+	u32 val;
+
+	val = readl(base + WDT_CNT);
+	val &= 0xffff;
+	val = val << 4;
+
+	return val;
+}
+
+static const struct watchdog_info sp_wdt_info = {
+	.identity	= DEVICE_NAME,
+	.options	= WDIOF_SETTIMEOUT |
+			  WDIOF_MAGICCLOSE |
+			  WDIOF_KEEPALIVEPING,
+};
+
+static const struct watchdog_ops sp_wdt_ops = {
+	.owner		= THIS_MODULE,
+	.start		= sp_wdt_start,
+	.stop		= sp_wdt_stop,
+	.ping		= sp_wdt_ping,
+	.get_timeleft	= sp_wdt_get_timeleft,
+	.restart	= sp_wdt_restart,
+};
+
+static void sp_clk_disable_unprepare(void *data)
+{
+	clk_disable_unprepare(data);
+}
+
+static void sp_reset_control_assert(void *data)
+{
+	reset_control_assert(data);
+}
+
+static int sp_wdt_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct sp_wdt_priv *priv;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(priv->clk))
+		return dev_err_probe(dev, PTR_ERR(priv->clk), "Failed to get clock\n");
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to enable clock\n");
+
+	ret = devm_add_action_or_reset(dev, sp_clk_disable_unprepare, priv->clk);
+	if (ret)
+		return ret;
+
+	/* The timer and watchdog shared the STC reset */
+	priv->rstc = devm_reset_control_get_shared(dev, NULL);
+	if (IS_ERR(priv->rstc))
+		return dev_err_probe(dev, PTR_ERR(priv->rstc), "Failed to get reset\n");
+
+	reset_control_deassert(priv->rstc);
+
+	ret = devm_add_action_or_reset(dev, sp_reset_control_assert, priv->rstc);
+	if (ret)
+		return ret;
+
+	priv->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	priv->wdev.info = &sp_wdt_info;
+	priv->wdev.ops = &sp_wdt_ops;
+	priv->wdev.timeout = SP_WDT_DEFAULT_TIMEOUT;
+	priv->wdev.max_hw_heartbeat_ms = SP_WDT_MAX_TIMEOUT * 1000;
+	priv->wdev.min_timeout = 1;
+	priv->wdev.parent = dev;
+
+	watchdog_set_drvdata(&priv->wdev, priv);
+	watchdog_init_timeout(&priv->wdev, timeout, dev);
+	watchdog_set_nowayout(&priv->wdev, nowayout);
+	watchdog_stop_on_reboot(&priv->wdev);
+	watchdog_set_restart_priority(&priv->wdev, 128);
+
+	return devm_watchdog_register_device(dev, &priv->wdev);
+}
+
+static const struct of_device_id sp_wdt_of_match[] = {
+	{.compatible = "sunplus,sp7021-wdt", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, sp_wdt_of_match);
+
+static struct platform_driver sp_wdt_driver = {
+	.probe = sp_wdt_probe,
+	.driver = {
+		   .name = DEVICE_NAME,
+		   .of_match_table = sp_wdt_of_match,
+	},
+};
+
+module_platform_driver(sp_wdt_driver);
+
+MODULE_AUTHOR("Xiantao Hu <xt.hu@cqplus1.com>");
+MODULE_DESCRIPTION("Sunplus Watchdog Timer Driver");
+MODULE_LICENSE("GPL");
-- 
2.33.1

Re: [PATCH v7 2/2] watchdog: Add watchdog driver for Sunplus SP7021

[Guenter Roeck]

On Fri, Mar 04, 2022 at 04:12:09PM +0800, Xiantao Hu wrote:
> Sunplus SP7021 requires watchdog timer support.
> Add watchdog driver to enable this.
> 
> Signed-off-by: Xiantao Hu <xt.hu@cqplus1.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
> Changes in v7:
>  - Addressed all comments from Mr. Guenter Roeck.
>    Fix sp_wdt_ping() and add comment to explain the calculation.
> 
>  MAINTAINERS                    |   1 +
>  drivers/watchdog/Kconfig       |  11 ++
>  drivers/watchdog/Makefile      |   1 +
>  drivers/watchdog/sunplus_wdt.c | 220 +++++++++++++++++++++++++++++++++
>  4 files changed, 233 insertions(+)
>  create mode 100644 drivers/watchdog/sunplus_wdt.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index fe6cc971c..a1b3d76e2 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -18247,6 +18247,7 @@ M:	Xiantao Hu <xt.hu@cqplus1.com>
>  L:	linux-watchdog@vger.kernel.org
>  S:	Maintained
>  F:	Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
> +F:	drivers/watchdog/sunplus_wdt.c
>  
>  SUPERH
>  M:	Yoshinori Sato <ysato@users.sourceforge.jp>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 9d222ba17..d3dbe8695 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -976,6 +976,17 @@ config MSC313E_WATCHDOG
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called msc313e_wdt.
>  
> +config SUNPLUS_WATCHDOG
> +	tristate "Sunplus watchdog support"
> +	depends on ARCH_SUNPLUS || COMPILE_TEST
> +	select WATCHDOG_CORE
> +	help
> +	  Say Y here to include support for the watchdog timer
> +	  in Sunplus SoCs.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called sunplus_wdt.
> +
>  # X86 (i386 + ia64 + x86_64) Architecture
>  
>  config ACQUIRE_WDT
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 2ee970641..0fa548ee6 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -93,6 +93,7 @@ obj-$(CONFIG_PM8916_WATCHDOG) += pm8916_wdt.o
>  obj-$(CONFIG_ARM_SMC_WATCHDOG) += arm_smc_wdt.o
>  obj-$(CONFIG_VISCONTI_WATCHDOG) += visconti_wdt.o
>  obj-$(CONFIG_MSC313E_WATCHDOG) += msc313e_wdt.o
> +obj-$(CONFIG_SUNPLUS_WATCHDOG) += sunplus_wdt.o
>  
>  # X86 (i386 + ia64 + x86_64) Architecture
>  obj-$(CONFIG_ACQUIRE_WDT) += acquirewdt.o
> diff --git a/drivers/watchdog/sunplus_wdt.c b/drivers/watchdog/sunplus_wdt.c
> new file mode 100644
> index 000000000..e2d8c532b
> --- /dev/null
> +++ b/drivers/watchdog/sunplus_wdt.c
> @@ -0,0 +1,220 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * sunplus Watchdog Driver
> + *
> + * Copyright (C) 2021 Sunplus Technology Co., Ltd.
> + *
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/platform_device.h>
> +#include <linux/reset.h>
> +#include <linux/watchdog.h>
> +
> +#define WDT_CTRL		0x00
> +#define WDT_CNT			0x04
> +
> +#define WDT_STOP		0x3877
> +#define WDT_RESUME		0x4A4B
> +#define WDT_CLRIRQ		0x7482
> +#define WDT_UNLOCK		0xAB00
> +#define WDT_LOCK		0xAB01
> +#define WDT_CONMAX		0xDEAF
> +
> +/* TIMEOUT_MAX = ffff0/90kHz =11.65, so longer than 11 seconds will time out. */
> +#define SP_WDT_MAX_TIMEOUT	11U
> +#define SP_WDT_DEFAULT_TIMEOUT	10
> +
> +#define STC_CLK			90000
> +
> +#define DEVICE_NAME		"sunplus-wdt"
> +
> +static unsigned int timeout;
> +module_param(timeout, int, 0);
> +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds");
> +
> +static bool nowayout = WATCHDOG_NOWAYOUT;
> +module_param(nowayout, bool, 0);
> +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
> +			__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
> +
> +struct sp_wdt_priv {
> +	struct watchdog_device wdev;
> +	void __iomem *base;
> +	struct clk *clk;
> +	struct reset_control *rstc;
> +};
> +
> +static int sp_wdt_restart(struct watchdog_device *wdev,
> +			  unsigned long action, void *data)
> +{
> +	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
> +	void __iomem *base = priv->base;
> +
> +	writel(WDT_STOP, base + WDT_CTRL);
> +	writel(WDT_UNLOCK, base + WDT_CTRL);
> +	writel(0x0001, base + WDT_CNT);
> +	writel(WDT_LOCK, base + WDT_CTRL);
> +	writel(WDT_RESUME, base + WDT_CTRL);
> +
> +	return 0;
> +}
> +
> +static int sp_wdt_ping(struct watchdog_device *wdev)
> +{
> +	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
> +	void __iomem *base = priv->base;
> +	u32 count;
> +
> +	if (wdev->timeout > SP_WDT_MAX_TIMEOUT) {
> +		/* WDT_CONMAX sets the count to the maximum (down-counting). */
> +		writel(WDT_CONMAX, base + WDT_CTRL);
> +	} else {
> +		writel(WDT_UNLOCK, base + WDT_CTRL);
> +		/*
> +		 * Watchdog timer is a 20-bit down-counting based on STC_CLK.
> +		 * This register bits[16:0] is from bit[19:4] of the watchdog
> +		 * timer counter.
> +		 */
> +		count = (wdev->timeout * STC_CLK) >> 4;
> +		writel(count, base + WDT_CNT);
> +		writel(WDT_LOCK, base + WDT_CTRL);
> +	}
> +
> +	return 0;
> +}
> +
> +static int sp_wdt_stop(struct watchdog_device *wdev)
> +{
> +	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
> +	void __iomem *base = priv->base;
> +
> +	writel(WDT_STOP, base + WDT_CTRL);
> +
> +	return 0;
> +}
> +
> +static int sp_wdt_start(struct watchdog_device *wdev)
> +{
> +	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
> +	void __iomem *base = priv->base;
> +
> +	writel(WDT_RESUME, base + WDT_CTRL);
> +
> +	return 0;
> +}
> +
> +static unsigned int sp_wdt_get_timeleft(struct watchdog_device *wdev)
> +{
> +	struct sp_wdt_priv *priv = watchdog_get_drvdata(wdev);
> +	void __iomem *base = priv->base;
> +	u32 val;
> +
> +	val = readl(base + WDT_CNT);
> +	val &= 0xffff;
> +	val = val << 4;
> +
> +	return val;
> +}
> +
> +static const struct watchdog_info sp_wdt_info = {
> +	.identity	= DEVICE_NAME,
> +	.options	= WDIOF_SETTIMEOUT |
> +			  WDIOF_MAGICCLOSE |
> +			  WDIOF_KEEPALIVEPING,
> +};
> +
> +static const struct watchdog_ops sp_wdt_ops = {
> +	.owner		= THIS_MODULE,
> +	.start		= sp_wdt_start,
> +	.stop		= sp_wdt_stop,
> +	.ping		= sp_wdt_ping,
> +	.get_timeleft	= sp_wdt_get_timeleft,
> +	.restart	= sp_wdt_restart,
> +};
> +
> +static void sp_clk_disable_unprepare(void *data)
> +{
> +	clk_disable_unprepare(data);
> +}
> +
> +static void sp_reset_control_assert(void *data)
> +{
> +	reset_control_assert(data);
> +}
> +
> +static int sp_wdt_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct sp_wdt_priv *priv;
> +	int ret;
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->clk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(priv->clk))
> +		return dev_err_probe(dev, PTR_ERR(priv->clk), "Failed to get clock\n");
> +
> +	ret = clk_prepare_enable(priv->clk);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to enable clock\n");
> +
> +	ret = devm_add_action_or_reset(dev, sp_clk_disable_unprepare, priv->clk);
> +	if (ret)
> +		return ret;
> +
> +	/* The timer and watchdog shared the STC reset */
> +	priv->rstc = devm_reset_control_get_shared(dev, NULL);
> +	if (IS_ERR(priv->rstc))
> +		return dev_err_probe(dev, PTR_ERR(priv->rstc), "Failed to get reset\n");
> +
> +	reset_control_deassert(priv->rstc);
> +
> +	ret = devm_add_action_or_reset(dev, sp_reset_control_assert, priv->rstc);
> +	if (ret)
> +		return ret;
> +
> +	priv->base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	priv->wdev.info = &sp_wdt_info;
> +	priv->wdev.ops = &sp_wdt_ops;
> +	priv->wdev.timeout = SP_WDT_DEFAULT_TIMEOUT;
> +	priv->wdev.max_hw_heartbeat_ms = SP_WDT_MAX_TIMEOUT * 1000;
> +	priv->wdev.min_timeout = 1;
> +	priv->wdev.parent = dev;
> +
> +	watchdog_set_drvdata(&priv->wdev, priv);
> +	watchdog_init_timeout(&priv->wdev, timeout, dev);
> +	watchdog_set_nowayout(&priv->wdev, nowayout);
> +	watchdog_stop_on_reboot(&priv->wdev);
> +	watchdog_set_restart_priority(&priv->wdev, 128);
> +
> +	return devm_watchdog_register_device(dev, &priv->wdev);
> +}
> +
> +static const struct of_device_id sp_wdt_of_match[] = {
> +	{.compatible = "sunplus,sp7021-wdt", },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, sp_wdt_of_match);
> +
> +static struct platform_driver sp_wdt_driver = {
> +	.probe = sp_wdt_probe,
> +	.driver = {
> +		   .name = DEVICE_NAME,
> +		   .of_match_table = sp_wdt_of_match,
> +	},
> +};
> +
> +module_platform_driver(sp_wdt_driver);
> +
> +MODULE_AUTHOR("Xiantao Hu <xt.hu@cqplus1.com>");
> +MODULE_DESCRIPTION("Sunplus Watchdog Timer Driver");
> +MODULE_LICENSE("GPL");

Re: [PATCH v7 1/2] dt-bindings: watchdog: Add watchdog yaml file for Sunplus SP7021

[Krzysztof Kozlowski]

On Fri, Mar 04, 2022 at 04:12:08PM +0800, Xiantao Hu wrote:
> This adds the documentation for the devicetree bindings of the Sunplus
> SP7021 watchdog driver, found from SP7021 SoCs and newer.
> 
> Reviewed-by: Rob Herring <robh@kernel.org>
> Signed-off-by: Xiantao Hu <xt.hu@cqplus1.com>
> ---
>  .../bindings/watchdog/sunplus,sp7021-wdt.yaml | 47 +++++++++++++++++++
>  MAINTAINERS                                   |  6 +++
>  2 files changed, 53 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml

Please use scripts/get_maintainer.pl on recent kernel (newest mainline or
recent linux-next) to get the list of people to CC.

> 
> diff --git a/Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml b/Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
> new file mode 100644
> index 000000000..9a9bfe150
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
> @@ -0,0 +1,47 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) Sunplus Co., Ltd. 2021
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/watchdog/sunplus,sp7021-wdt.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Sunplus SoCs Watchdog Device Tree Bindings

s/Device Tree Bindings//

> +
> +maintainers:
> +  - XianTao Hu <xt.hu@cqplus1.com>
> +
> +allOf:
> +  - $ref: watchdog.yaml#
> +
> +properties:
> +  compatible:
> +    const: sunplus,sp7021-wdt
> +
> +  reg:
> +    items:
> +      - description: watchdog registers regions
> +      - description: miscellaneous control registers regions
> +
> +  clocks:
> +    maxItems: 1
> +
> +  resets:
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - resets
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    watchdog: watchdog@9c000630 {
> +        compatible = "sunplus,sp7021-wdt";
> +        reg = <0x9c000630 0x08>, <0x9C000274 0x04>;

lowercase hex (Second reg)

Can be fixed while applying, so in such case:
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>

Best regards,
Krzysztof

RE: [PATCH v7 1/2] dt-bindings: watchdog: Add watchdog yaml file for Sunplus SP7021

[xt.hu[胡先韬]]

Dear Krzysztof
	Thanks for your review.

> -----Original Message-----
> From: Krzysztof Kozlowski [mailto:krzk@kernel.org]
> Sent: Monday, March 21, 2022 7:10 PM
> To: xt.hu[胡先韬] <xt.hu@cqplus1.com>
> Cc: wim@linux-watchdog.org; p.zabel@pengutronix.de; linux-kernel@vger.kernel.org;
> linux-watchdog@vger.kernel.org; linux@roeck-us.net; robh+dt@kernel.org; devicetree@vger.kernel.org;
> Wells Lu 呂芳騰 <wells.lu@sunplus.com>; qinjian[覃健] <qinjian@cqplus1.com>; Rob Herring
> <robh@kernel.org>
> Subject: Re: [PATCH v7 1/2] dt-bindings: watchdog: Add watchdog yaml file for Sunplus SP7021
> 
> On Fri, Mar 04, 2022 at 04:12:08PM +0800, Xiantao Hu wrote:
> > This adds the documentation for the devicetree bindings of the Sunplus
> > SP7021 watchdog driver, found from SP7021 SoCs and newer.
> >
> > Reviewed-by: Rob Herring <robh@kernel.org>
> > Signed-off-by: Xiantao Hu <xt.hu@cqplus1.com>
> > ---
> >  .../bindings/watchdog/sunplus,sp7021-wdt.yaml | 47 +++++++++++++++++++
> >  MAINTAINERS                                   |  6 +++
> >  2 files changed, 53 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
> 
> Please use scripts/get_maintainer.pl on recent kernel (newest mainline or
> recent linux-next) to get the list of people to CC.
> 

I will do it in the next patch.

> >
> > diff --git a/Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
> b/Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
> > new file mode 100644
> > index 000000000..9a9bfe150
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/watchdog/sunplus,sp7021-wdt.yaml
> > @@ -0,0 +1,47 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +# Copyright (C) Sunplus Co., Ltd. 2021
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/watchdog/sunplus,sp7021-wdt.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Sunplus SoCs Watchdog Device Tree Bindings
> 
> s/Device Tree Bindings//
> 

I will drop the string "Device Tree Bindings".

> > +
> > +maintainers:
> > +  - XianTao Hu <xt.hu@cqplus1.com>
> > +
> > +allOf:
> > +  - $ref: watchdog.yaml#
> > +
> > +properties:
> > +  compatible:
> > +    const: sunplus,sp7021-wdt
> > +
> > +  reg:
> > +    items:
> > +      - description: watchdog registers regions
> > +      - description: miscellaneous control registers regions
> > +
> > +  clocks:
> > +    maxItems: 1
> > +
> > +  resets:
> > +    maxItems: 1
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - clocks
> > +  - resets
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    watchdog: watchdog@9c000630 {
> > +        compatible = "sunplus,sp7021-wdt";
> > +        reg = <0x9c000630 0x08>, <0x9C000274 0x04>;
> 
> lowercase hex (Second reg)
> 

I just realized the driver don't use second reg anymore. I will drop it and 
modify the description of reg.

> Can be fixed while applying, so in such case:
> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
> 

I got it.

Best regards,
Xian-tao
> Best regards,
> Krzysztof