diff mbox

[V7,3/3] watchdog: s3c2410_wdt: add device tree support and use syscon regmap interface to configure pmu register

Message ID 1384173897-16106-4-git-send-email-l.krishna@samsung.com
State Superseded, archived
Headers show

Commit Message

Leela Krishna Amudala Nov. 11, 2013, 12:44 p.m. UTC 
Add device tree support and use syscon regmap interface to configure
AUTOMATIC_WDT_RESET_DISABLE and MASK_WDT_RESET_REQUEST registers of PMU
to mask/unmask enable/disable of watchdog in probe and s2r scenarios.

Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com>
---
 .../devicetree/bindings/watchdog/samsung-wdt.txt   |   21 ++-
 drivers/watchdog/Kconfig                           |    1 +
 drivers/watchdog/s3c2410_wdt.c                     |  154 +++++++++++++++++++-
 3 files changed, 167 insertions(+), 9 deletions(-)

Comments

Tomasz Figa Nov. 11, 2013, 1:23 p.m. UTC | #1 
Hi Leela,

Thanks for addressing my comments for previous version. However now this
won't even build when CONFIG_OF is disabled. See my comments inline.

On Monday 11 of November 2013 18:14:57 Leela Krishna Amudala wrote:
> Add device tree support and use syscon regmap interface to configure
> AUTOMATIC_WDT_RESET_DISABLE and MASK_WDT_RESET_REQUEST registers of PMU
> to mask/unmask enable/disable of watchdog in probe and s2r scenarios.
> 
> Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com>
> ---
>  .../devicetree/bindings/watchdog/samsung-wdt.txt   |   21 ++-
>  drivers/watchdog/Kconfig                           |    1 +
>  drivers/watchdog/s3c2410_wdt.c                     |  154 +++++++++++++++++++-
>  3 files changed, 167 insertions(+), 9 deletions(-)
[snip]
> diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
> index 23aad7c..b57ccae 100644
> --- a/drivers/watchdog/s3c2410_wdt.c
> +++ b/drivers/watchdog/s3c2410_wdt.c
[snip]
> @@ -94,8 +107,56 @@ struct s3c2410_wdt {
>  	unsigned long		wtdat_save;
>  	struct watchdog_device	wdt_device;
>  	struct notifier_block	freq_transition;
> +	struct s3c2410_wdt_variant *pmu_config;
> +	struct regmap *pmureg;
> +};
> +
> +#ifdef CONFIG_OF
> +static const struct s3c2410_wdt_variant pmu_config_s3c2410 = {
> +	.quirks = 0
> +};
> +
> +static const struct s3c2410_wdt_variant pmu_config_5250  = {
> +	.disable_reg = WDT_DISABLE_REG_OFFSET,
> +	.mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
> +	.mask_bit = 20,
> +	.quirks = QUIRK_NEEDS_PMU_CONFIG
>  };
>  
> +static const struct s3c2410_wdt_variant pmu_config_5420 = {
> +	.disable_reg = WDT_DISABLE_REG_OFFSET,
> +	.mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
> +	.mask_bit = 0,
> +	.quirks = QUIRK_NEEDS_PMU_CONFIG
> +};

The three variant data structs above are under #ifdef CONFIG_OF, while
they are always needed for the platform match table.

However, since Exynos supports only DT-based device instantation,
I would move only the basic pmu_config_s3c2410 out of the ifdef and
limit the platform match table only to this single variant.

> +
> +static const struct of_device_id s3c2410_wdt_match[] = {
> +	{ .compatible = "samsung,s3c2410-wdt",
> +	  .data = &pmu_config_s3c2410 },
> +	{ .compatible = "samsung,exynos5250-wdt",
> +	  .data = &pmu_config_5250 },
> +	{ .compatible = "samsung,exynos5420-wdt",
> +	  .data = &pmu_config_5420 },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
> +#endif
> +
> +static const struct platform_device_id s3c_wdt_driver_ids[] = {

nit: For consistency with other names in this file, what about
calling this s3c2410_wdt_ids[] instead?

> +	{
> +		.name = "s3c2410-wdt",
> +		.driver_data = (unsigned long)&pmu_config_s3c2410,
> +	}, {
> +		.name = "exynos5250-wdt",
> +		.driver_data = (unsigned long)&pmu_config_5250,
> +	}, {
> +		.name = "exynos5420-wdt",
> +		.driver_data = (unsigned long)&pmu_config_5420,
> +	},

So, generally, you don't need the two Exynos variants above in this array.

Otherwise, the patch is fine.

Best regards,
Tomasz

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Leela Krishna Amudala Nov. 12, 2013, 6 a.m. UTC | #2 
Hi Tomasz,

Thanks for reviewing the patch

On Mon, Nov 11, 2013 at 6:53 PM, Tomasz Figa <tomasz.figa@gmail.com> wrote:
> Hi Leela,
>
> Thanks for addressing my comments for previous version. However now this
> won't even build when CONFIG_OF is disabled. See my comments inline.
>

Yes, you are right, I didn't compile it disabling CONFIG_OF

> On Monday 11 of November 2013 18:14:57 Leela Krishna Amudala wrote:
>> Add device tree support and use syscon regmap interface to configure
>> AUTOMATIC_WDT_RESET_DISABLE and MASK_WDT_RESET_REQUEST registers of PMU
>> to mask/unmask enable/disable of watchdog in probe and s2r scenarios.
>>
>> Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com>
>> ---
>>  .../devicetree/bindings/watchdog/samsung-wdt.txt   |   21 ++-
>>  drivers/watchdog/Kconfig                           |    1 +
>>  drivers/watchdog/s3c2410_wdt.c                     |  154 +++++++++++++++++++-
>>  3 files changed, 167 insertions(+), 9 deletions(-)
> [snip]
>> diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
>> index 23aad7c..b57ccae 100644
>> --- a/drivers/watchdog/s3c2410_wdt.c
>> +++ b/drivers/watchdog/s3c2410_wdt.c
> [snip]
>> @@ -94,8 +107,56 @@ struct s3c2410_wdt {
>>       unsigned long           wtdat_save;
>>       struct watchdog_device  wdt_device;
>>       struct notifier_block   freq_transition;
>> +     struct s3c2410_wdt_variant *pmu_config;
>> +     struct regmap *pmureg;
>> +};
>> +
>> +#ifdef CONFIG_OF
>> +static const struct s3c2410_wdt_variant pmu_config_s3c2410 = {
>> +     .quirks = 0
>> +};
>> +
>> +static const struct s3c2410_wdt_variant pmu_config_5250  = {
>> +     .disable_reg = WDT_DISABLE_REG_OFFSET,
>> +     .mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
>> +     .mask_bit = 20,
>> +     .quirks = QUIRK_NEEDS_PMU_CONFIG
>>  };
>>
>> +static const struct s3c2410_wdt_variant pmu_config_5420 = {
>> +     .disable_reg = WDT_DISABLE_REG_OFFSET,
>> +     .mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
>> +     .mask_bit = 0,
>> +     .quirks = QUIRK_NEEDS_PMU_CONFIG
>> +};
>
> The three variant data structs above are under #ifdef CONFIG_OF, while
> they are always needed for the platform match table.
>
> However, since Exynos supports only DT-based device instantation,
> I would move only the basic pmu_config_s3c2410 out of the ifdef and
> limit the platform match table only to this single variant.
>

Okay, Taken care

>> +
>> +static const struct of_device_id s3c2410_wdt_match[] = {
>> +     { .compatible = "samsung,s3c2410-wdt",
>> +       .data = &pmu_config_s3c2410 },
>> +     { .compatible = "samsung,exynos5250-wdt",
>> +       .data = &pmu_config_5250 },
>> +     { .compatible = "samsung,exynos5420-wdt",
>> +       .data = &pmu_config_5420 },
>> +     {},
>> +};
>> +MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
>> +#endif
>> +
>> +static const struct platform_device_id s3c_wdt_driver_ids[] = {
>
> nit: For consistency with other names in this file, what about
> calling this s3c2410_wdt_ids[] instead?
>

Okay, modified

>> +     {
>> +             .name = "s3c2410-wdt",
>> +             .driver_data = (unsigned long)&pmu_config_s3c2410,
>> +     }, {
>> +             .name = "exynos5250-wdt",
>> +             .driver_data = (unsigned long)&pmu_config_5250,
>> +     }, {
>> +             .name = "exynos5420-wdt",
>> +             .driver_data = (unsigned long)&pmu_config_5420,
>> +     },
>
> So, generally, you don't need the two Exynos variants above in this array.
>

Yes, removed from the array

Best Wishes,
Leela Krishna

> Otherwise, the patch is fine.
>
> Best regards,
> Tomasz
>
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diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
index 2aa486c..5dea363 100644
--- a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
@@ -5,10 +5,29 @@  after a preset amount of time during which the WDT reset event has not
 occurred.
 
 Required properties:
-- compatible : should be "samsung,s3c2410-wdt"
+- compatible : should be one among the following
+	(a) "samsung,s3c2410-wdt" for Exynos4 and previous SoCs
+	(b) "samsung,exynos5250-wdt" for Exynos5250
+	(c) "samsung,exynos5420-wdt" for Exynos5420
+
 - reg : base physical address of the controller and length of memory mapped
 	region.
 - interrupts : interrupt number to the cpu.
+- samsung,syscon-phandle : reference to syscon node (This property required only
+	in case of compatible being "samsung,exynos5250-wdt" or "samsung,exynos5420-wdt".
+	In case of Exynos5250 and 5420 this property points to syscon node holding the PMU
+	base address)
 
 Optional properties:
 - timeout-sec : contains the watchdog timeout in seconds.
+
+Example:
+
+watchdog@101D0000 {
+	compatible = "samsung,exynos5250-wdt";
+	reg = <0x101D0000 0x100>;
+	interrupts = <0 42 0>;
+	clocks = <&clock 336>;
+	clock-names = "watchdog";
+	samsung,syscon-phandle = <&pmu_sys_reg>;
+};
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index d1d53f3..0d272ae 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -188,6 +188,7 @@  config S3C2410_WATCHDOG
 	tristate "S3C2410 Watchdog"
 	depends on HAVE_S3C2410_WATCHDOG
 	select WATCHDOG_CORE
+	select MFD_SYSCON if ARCH_EXYNOS5
 	help
 	  Watchdog timer block in the Samsung SoCs. This will reboot
 	  the system when the timer expires with the watchdog enabled.
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index 23aad7c..b57ccae 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -41,6 +41,8 @@ 
 #include <linux/slab.h>
 #include <linux/err.h>
 #include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
 
 #define S3C2410_WTCON		0x00
 #define S3C2410_WTDAT		0x04
@@ -61,6 +63,10 @@ 
 #define CONFIG_S3C2410_WATCHDOG_ATBOOT		(0)
 #define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME	(15)
 
+#define WDT_DISABLE_REG_OFFSET		0x0408
+#define WDT_MASK_RESET_REG_OFFSET	0x040c
+#define QUIRK_NEEDS_PMU_CONFIG		(1 << 0)
+
 static bool nowayout	= WATCHDOG_NOWAYOUT;
 static int tmr_margin;
 static int tmr_atboot	= CONFIG_S3C2410_WATCHDOG_ATBOOT;
@@ -84,6 +90,13 @@  MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, "
 			"0 to reboot (default 0)");
 MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug (default 0)");
 
+struct s3c2410_wdt_variant {
+	int disable_reg;
+	int mask_reset_reg;
+	int mask_bit;
+	u32 quirks;
+};
+
 struct s3c2410_wdt {
 	struct device		*dev;
 	struct clk		*clock;
@@ -94,8 +107,56 @@  struct s3c2410_wdt {
 	unsigned long		wtdat_save;
 	struct watchdog_device	wdt_device;
 	struct notifier_block	freq_transition;
+	struct s3c2410_wdt_variant *pmu_config;
+	struct regmap *pmureg;
+};
+
+#ifdef CONFIG_OF
+static const struct s3c2410_wdt_variant pmu_config_s3c2410 = {
+	.quirks = 0
+};
+
+static const struct s3c2410_wdt_variant pmu_config_5250  = {
+	.disable_reg = WDT_DISABLE_REG_OFFSET,
+	.mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
+	.mask_bit = 20,
+	.quirks = QUIRK_NEEDS_PMU_CONFIG
 };
 
+static const struct s3c2410_wdt_variant pmu_config_5420 = {
+	.disable_reg = WDT_DISABLE_REG_OFFSET,
+	.mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
+	.mask_bit = 0,
+	.quirks = QUIRK_NEEDS_PMU_CONFIG
+};
+
+static const struct of_device_id s3c2410_wdt_match[] = {
+	{ .compatible = "samsung,s3c2410-wdt",
+	  .data = &pmu_config_s3c2410 },
+	{ .compatible = "samsung,exynos5250-wdt",
+	  .data = &pmu_config_5250 },
+	{ .compatible = "samsung,exynos5420-wdt",
+	  .data = &pmu_config_5420 },
+	{},
+};
+MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
+#endif
+
+static const struct platform_device_id s3c_wdt_driver_ids[] = {
+	{
+		.name = "s3c2410-wdt",
+		.driver_data = (unsigned long)&pmu_config_s3c2410,
+	}, {
+		.name = "exynos5250-wdt",
+		.driver_data = (unsigned long)&pmu_config_5250,
+	}, {
+		.name = "exynos5420-wdt",
+		.driver_data = (unsigned long)&pmu_config_5420,
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(platform, s3c_wdt_driver_ids);
+
 /* watchdog control routines */
 
 #define DBG(fmt, ...)					\
@@ -111,6 +172,30 @@  static inline struct s3c2410_wdt *freq_to_wdt(struct notifier_block *nb)
 	return container_of(nb, struct s3c2410_wdt, freq_transition);
 }
 
+static int s3c2410wdt_mask_and_disable_reset(struct s3c2410_wdt *wdt, bool mask)
+{
+	int ret;
+	u32 mask_val = 1 << wdt->pmu_config->mask_bit;
+	u32 val = 0;
+
+	if (mask)
+		val = mask_val;
+
+	ret = regmap_update_bits(wdt->pmureg,
+			wdt->pmu_config->disable_reg,
+			mask_val, val);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_update_bits(wdt->pmureg,
+			wdt->pmu_config->mask_reset_reg,
+			mask_val, val);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
 static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
 {
 	struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
@@ -332,6 +417,20 @@  static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt)
 }
 #endif
 
+/* s3c2410_get_wdt_driver_data */
+static inline struct s3c2410_wdt_variant *
+get_wdt_drv_data(struct platform_device *pdev)
+{
+	if (pdev->dev.of_node) {
+		const struct of_device_id *match;
+		match = of_match_node(s3c2410_wdt_match, pdev->dev.of_node);
+		return (struct s3c2410_wdt_variant *)match->data;
+	} else {
+		return (struct s3c2410_wdt_variant *)
+			platform_get_device_id(pdev)->driver_data;
+	}
+}
+
 static int s3c2410wdt_probe(struct platform_device *pdev)
 {
 	struct device *dev;
@@ -354,6 +453,16 @@  static int s3c2410wdt_probe(struct platform_device *pdev)
 	spin_lock_init(&wdt->lock);
 	wdt->wdt_device = s3c2410_wdd;
 
+	wdt->pmu_config = get_wdt_drv_data(pdev);
+	if (wdt->pmu_config->quirks & QUIRK_NEEDS_PMU_CONFIG) {
+		wdt->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node,
+							"samsung,syscon-phandle");
+		if (IS_ERR(wdt->pmureg)) {
+			dev_err(dev, "syscon regmap lookup failed.\n");
+			return PTR_ERR(wdt->pmureg);
+		}
+	}
+
 	wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (wdt_irq == NULL) {
 		dev_err(dev, "no irq resource specified\n");
@@ -444,6 +553,14 @@  static int s3c2410wdt_probe(struct platform_device *pdev)
 		 (wtcon & S3C2410_WTCON_RSTEN) ? "en" : "dis",
 		 (wtcon & S3C2410_WTCON_INTEN) ? "en" : "dis");
 
+	if (wdt->pmu_config->quirks & QUIRK_NEEDS_PMU_CONFIG) {
+		ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
+		if (ret < 0) {
+			dev_warn(wdt->dev, "failed to update pmu register");
+			goto err_cpufreq;
+		}
+	}
+
 	return 0;
 
  err_cpufreq:
@@ -459,8 +576,15 @@  static int s3c2410wdt_probe(struct platform_device *pdev)
 
 static int s3c2410wdt_remove(struct platform_device *dev)
 {
+	int ret;
 	struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
 
+	if (wdt->pmu_config->quirks & QUIRK_NEEDS_PMU_CONFIG) {
+		ret = s3c2410wdt_mask_and_disable_reset(wdt, true);
+		if (ret < 0)
+			dev_warn(wdt->dev, "failed to update pmu register");
+	}
+
 	watchdog_unregister_device(&wdt->wdt_device);
 
 	s3c2410wdt_cpufreq_deregister(wdt);
@@ -473,8 +597,15 @@  static int s3c2410wdt_remove(struct platform_device *dev)
 
 static void s3c2410wdt_shutdown(struct platform_device *dev)
 {
+	int ret;
 	struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
 
+	if (wdt->pmu_config->quirks & QUIRK_NEEDS_PMU_CONFIG) {
+		ret = s3c2410wdt_mask_and_disable_reset(wdt, true);
+		if (ret < 0)
+			dev_warn(wdt->dev, "failed to update pmu register");
+	}
+
 	s3c2410wdt_stop(&wdt->wdt_device);
 }
 
@@ -482,12 +613,19 @@  static void s3c2410wdt_shutdown(struct platform_device *dev)
 
 static int s3c2410wdt_suspend(struct device *dev)
 {
+	int ret;
 	struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
 
 	/* Save watchdog state, and turn it off. */
 	wdt->wtcon_save = readl(wdt->reg_base + S3C2410_WTCON);
 	wdt->wtdat_save = readl(wdt->reg_base + S3C2410_WTDAT);
 
+	if (wdt->pmu_config->quirks & QUIRK_NEEDS_PMU_CONFIG) {
+		ret = s3c2410wdt_mask_and_disable_reset(wdt, true);
+		if (ret < 0)
+			dev_warn(wdt->dev, "failed to update pmu register");
+	}
+
 	/* Note that WTCNT doesn't need to be saved. */
 	s3c2410wdt_stop(&wdt->wdt_device);
 
@@ -496,6 +634,7 @@  static int s3c2410wdt_suspend(struct device *dev)
 
 static int s3c2410wdt_resume(struct device *dev)
 {
+	int ret;
 	struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
 
 	/* Restore watchdog state. */
@@ -503,6 +642,12 @@  static int s3c2410wdt_resume(struct device *dev)
 	writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTCNT);/* Reset count */
 	writel(wdt->wtcon_save, wdt->reg_base + S3C2410_WTCON);
 
+	if (wdt->pmu_config->quirks & QUIRK_NEEDS_PMU_CONFIG) {
+		ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
+		if (ret < 0)
+			dev_warn(wdt->dev, "failed to update pmu register");
+	}
+
 	dev_info(dev, "watchdog %sabled\n",
 		(wdt->wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis");
 
@@ -513,18 +658,11 @@  static int s3c2410wdt_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(s3c2410wdt_pm_ops, s3c2410wdt_suspend,
 			s3c2410wdt_resume);
 
-#ifdef CONFIG_OF
-static const struct of_device_id s3c2410_wdt_match[] = {
-	{ .compatible = "samsung,s3c2410-wdt" },
-	{},
-};
-MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
-#endif
-
 static struct platform_driver s3c2410wdt_driver = {
 	.probe		= s3c2410wdt_probe,
 	.remove		= s3c2410wdt_remove,
 	.shutdown	= s3c2410wdt_shutdown,
+	.id_table	= s3c_wdt_driver_ids,
 	.driver		= {
 		.owner	= THIS_MODULE,
 		.name	= "s3c2410-wdt",