[Patch v1 6/7] DA9055 Watchdog driver

[Patch v1 6/7] DA9055 Watchdog driver

[Ashish Jangam]

This is the Watchdog patch for the DA9055 PMIC. This patch has got
dependency on the DA9055 MFD core.

This patch is functionally tested on SMDK6410

Signed-off-by: David Dajun Chen <dchen@diasemi.com>
Signed-off-by: Ashish Jangam <ashish.jangam@kpitcummins.com>
---
 drivers/watchdog/Kconfig      |   10 ++
 drivers/watchdog/Makefile     |    1 +
 drivers/watchdog/da9055_wdt.c |  227 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 238 insertions(+), 0 deletions(-)
 create mode 100644 drivers/watchdog/da9055_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 53d7571..eb51bf2 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -76,6 +76,16 @@ config DA9052_WATCHDOG
           Alternatively say M to compile the driver as a module,
           which will be called da9052_wdt.
 
+config DA9055_WATCHDOG
+	tristate "Dialog Semiconductor DA9055 Watchdog"
+	depends on MFD_DA9055
+	help
+	  If you say yes here you get support for watchdog on the Dialog
+	  Semiconductor DA9055 PMIC.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called da9055_wdt.
+
 config WM831X_WATCHDOG
 	tristate "WM831x watchdog"
 	depends on MFD_WM831X
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 572b39b..97bbdb3 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -164,6 +164,7 @@ obj-$(CONFIG_XEN_WDT) += xen_wdt.o
 
 # Architecture Independent
 obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
+obj-$(CONFIG_DA9055_WATCHDOG) += da9055_wdt.o
 obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
 obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
 obj-$(CONFIG_MAX63XX_WATCHDOG) += max63xx_wdt.o
diff --git a/drivers/watchdog/da9055_wdt.c b/drivers/watchdog/da9055_wdt.c
new file mode 100644
index 0000000..4cb8689
--- /dev/null
+++ b/drivers/watchdog/da9055_wdt.c
@@ -0,0 +1,227 @@
+/*
+ * System monitoring driver for DA9055 PMICs.
+ *
+ * Copyright(c) 2012 Dialog Semiconductor Ltd.
+ *
+ * Author: David Dajun Chen <dchen@diasemi.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+#include <linux/watchdog.h>
+#include <linux/delay.h>
+
+#include <linux/mfd/da9055/core.h>
+#include <linux/mfd/da9055/reg.h>
+
+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) ")");
+
+#define DA9055_DEF_TIMEOUT	4
+#define DA9055_TWDMIN		256
+
+struct da9055_wdt_data {
+	struct watchdog_device wdt;
+	struct da9055 *da9055;
+	struct kref kref;
+};
+
+static const struct {
+	u8 reg_val;
+	int user_time;  /* In seconds */
+} da9055_wdt_maps[] = {
+	{ 0, 0 },
+	{ 1, 2 },
+	{ 2, 4 },
+	{ 3, 8 },
+	{ 4, 16 },
+	{ 5, 32 },
+	{ 5, 33 },  /* Actual time  32.768s so included both 32s and 33s */
+	{ 6, 65 },
+	{ 6, 66 },  /* Actual time 65.536s so include both, 65s and 66s */
+	{ 7, 131 },
+};
+
+static int da9055_wdt_set_timeout(struct watchdog_device *wdt_dev,
+				  unsigned int timeout)
+{
+	struct da9055_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
+	struct da9055 *da9055 = driver_data->da9055;
+	int ret, i;
+
+	for (i = 0; i < ARRAY_SIZE(da9055_wdt_maps); i++)
+		if (da9055_wdt_maps[i].user_time == timeout)
+			break;
+
+	if (i == ARRAY_SIZE(da9055_wdt_maps))
+		ret = -EINVAL;
+	else
+		ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B,
+					DA9055_TWDSCALE_MASK,
+					da9055_wdt_maps[i].reg_val <<
+					DA9055_TWDSCALE_SHIFT);
+	if (ret < 0)
+		dev_err(da9055->dev,
+			"Failed to update timescale bit, %d\n", ret);
+
+	wdt_dev->timeout = timeout;
+
+	return ret;
+}
+
+static int da9055_wdt_ping(struct watchdog_device *wdt_dev)
+{
+	struct da9055_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
+	struct da9055 *da9055 = driver_data->da9055;
+	int ret;
+
+	/*
+	 * We have a minimum time for watchdog window called TWDMIN. A write
+	 * to the watchdog before this elapsed time will cause an error.
+	 */
+	mdelay(DA9055_TWDMIN);
+
+	/* Reset the watchdog timer */
+	ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_E,
+				DA9055_WATCHDOG_MASK, 1);
+
+	return ret;
+}
+
+static void da9055_wdt_release_resources(struct kref *r)
+{
+	struct da9055_wdt_data *driver_data =
+		container_of(r, struct da9055_wdt_data, kref);
+
+	kfree(driver_data);
+}
+
+static void da9055_wdt_ref(struct watchdog_device *wdt_dev)
+{
+	struct da9055_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
+
+	kref_get(&driver_data->kref);
+}
+
+static void da9055_wdt_unref(struct watchdog_device *wdt_dev)
+{
+	struct da9055_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
+
+	kref_put(&driver_data->kref, da9055_wdt_release_resources);
+}
+
+static int da9055_wdt_start(struct watchdog_device *wdt_dev)
+{
+	return da9055_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
+}
+
+static int da9055_wdt_stop(struct watchdog_device *wdt_dev)
+{
+	return da9055_wdt_set_timeout(wdt_dev, 0);
+}
+
+static struct watchdog_info da9055_wdt_info = {
+	.options	= WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+	.identity	= "DA9055 Watchdog",
+};
+
+static const struct watchdog_ops da9055_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = da9055_wdt_start,
+	.stop = da9055_wdt_stop,
+	.ping = da9055_wdt_ping,
+	.set_timeout = da9055_wdt_set_timeout,
+	.ref = da9055_wdt_ref,
+	.unref = da9055_wdt_unref,
+};
+
+static int __devinit da9055_wdt_probe(struct platform_device *pdev)
+{
+	struct da9055 *da9055 = dev_get_drvdata(pdev->dev.parent);
+	struct da9055_wdt_data *driver_data;
+	struct watchdog_device *da9055_wdt;
+	int ret;
+
+	driver_data = devm_kzalloc(&pdev->dev, sizeof(*driver_data),
+				   GFP_KERNEL);
+	if (!driver_data) {
+		dev_err(da9055->dev, "Failed to allocate watchdog device\n");
+		return -ENOMEM;
+	}
+
+	driver_data->da9055 = da9055;
+
+	da9055_wdt = &driver_data->wdt;
+
+	da9055_wdt->timeout = DA9055_DEF_TIMEOUT;
+	da9055_wdt->info = &da9055_wdt_info;
+	da9055_wdt->ops = &da9055_wdt_ops;
+	watchdog_set_nowayout(da9055_wdt, nowayout);
+	watchdog_set_drvdata(da9055_wdt, driver_data);
+
+	kref_init(&driver_data->kref);
+
+	ret = da9055_wdt_stop(da9055_wdt);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to stop watchdog, %d\n", ret);
+		goto err;
+	}
+
+	dev_set_drvdata(&pdev->dev, driver_data);
+
+	ret = watchdog_register_device(&driver_data->wdt);
+	if (ret != 0)
+		dev_err(da9055->dev, "watchdog_register_device() failed: %d\n",
+			ret);
+
+err:
+	return ret;
+}
+
+static int __devexit da9055_wdt_remove(struct platform_device *pdev)
+{
+	struct da9055_wdt_data *driver_data = dev_get_drvdata(&pdev->dev);
+
+	watchdog_unregister_device(&driver_data->wdt);
+	kref_put(&driver_data->kref, da9055_wdt_release_resources);
+
+	return 0;
+}
+
+static struct platform_driver da9055_wdt_driver = {
+	.probe = da9055_wdt_probe,
+	.remove = __devexit_p(da9055_wdt_remove),
+	.driver = {
+		.name	= "da9055-watchdog",
+	},
+};
+
+static int __init da9055_wdt_init(void)
+{
+	return platform_driver_register(&da9055_wdt_driver);
+}
+module_init(da9055_wdt_init);
+
+static void __exit da9055_wdt_exit(void)
+{
+	platform_driver_unregister(&da9055_wdt_driver);
+}
+module_exit(da9055_wdt_exit);
+
+MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
+MODULE_DESCRIPTION("DA9055 watchdog");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:da9055-watchdog");
-- 
1.7.0.4

Re: [Patch v1 6/7] DA9055 Watchdog driver

[Ashish Jangam]

Any update on this patch?
On Fri, 2012-09-14 at 19:03 +0530, Ashish Jangam wrote:
> This is the Watchdog patch for the DA9055 PMIC. This patch has got
> dependency on the DA9055 MFD core.
> 
> This patch is functionally tested on SMDK6410
> 
> Signed-off-by: David Dajun Chen <dchen@diasemi.com>
> Signed-off-by: Ashish Jangam <ashish.jangam@kpitcummins.com>
> ---
>  drivers/watchdog/Kconfig      |   10 ++
>  drivers/watchdog/Makefile     |    1 +
>  drivers/watchdog/da9055_wdt.c |  227 +++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 238 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/watchdog/da9055_wdt.c
> 
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 53d7571..eb51bf2 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -76,6 +76,16 @@ config DA9052_WATCHDOG
>            Alternatively say M to compile the driver as a module,
>            which will be called da9052_wdt.
>  
> +config DA9055_WATCHDOG
> +	tristate "Dialog Semiconductor DA9055 Watchdog"
> +	depends on MFD_DA9055
> +	help
> +	  If you say yes here you get support for watchdog on the Dialog
> +	  Semiconductor DA9055 PMIC.
> +
> +	  This driver can also be built as a module.  If so, the module
> +	  will be called da9055_wdt.
> +
>  config WM831X_WATCHDOG
>  	tristate "WM831x watchdog"
>  	depends on MFD_WM831X
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 572b39b..97bbdb3 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -164,6 +164,7 @@ obj-$(CONFIG_XEN_WDT) += xen_wdt.o
>  
>  # Architecture Independent
>  obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
> +obj-$(CONFIG_DA9055_WATCHDOG) += da9055_wdt.o
>  obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
>  obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
>  obj-$(CONFIG_MAX63XX_WATCHDOG) += max63xx_wdt.o
> diff --git a/drivers/watchdog/da9055_wdt.c b/drivers/watchdog/da9055_wdt.c
> new file mode 100644
> index 0000000..4cb8689
> --- /dev/null
> +++ b/drivers/watchdog/da9055_wdt.c
> @@ -0,0 +1,227 @@
> +/*
> + * System monitoring driver for DA9055 PMICs.
> + *
> + * Copyright(c) 2012 Dialog Semiconductor Ltd.
> + *
> + * Author: David Dajun Chen <dchen@diasemi.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/types.h>
> +#include <linux/kernel.h>
> +#include <linux/slab.h>
> +#include <linux/platform_device.h>
> +#include <linux/watchdog.h>
> +#include <linux/watchdog.h>
> +#include <linux/delay.h>
> +
> +#include <linux/mfd/da9055/core.h>
> +#include <linux/mfd/da9055/reg.h>
> +
> +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) ")");
> +
> +#define DA9055_DEF_TIMEOUT	4
> +#define DA9055_TWDMIN		256
> +
> +struct da9055_wdt_data {
> +	struct watchdog_device wdt;
> +	struct da9055 *da9055;
> +	struct kref kref;
> +};
> +
> +static const struct {
> +	u8 reg_val;
> +	int user_time;  /* In seconds */
> +} da9055_wdt_maps[] = {
> +	{ 0, 0 },
> +	{ 1, 2 },
> +	{ 2, 4 },
> +	{ 3, 8 },
> +	{ 4, 16 },
> +	{ 5, 32 },
> +	{ 5, 33 },  /* Actual time  32.768s so included both 32s and 33s */
> +	{ 6, 65 },
> +	{ 6, 66 },  /* Actual time 65.536s so include both, 65s and 66s */
> +	{ 7, 131 },
> +};
> +
> +static int da9055_wdt_set_timeout(struct watchdog_device *wdt_dev,
> +				  unsigned int timeout)
> +{
> +	struct da9055_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
> +	struct da9055 *da9055 = driver_data->da9055;
> +	int ret, i;
> +
> +	for (i = 0; i < ARRAY_SIZE(da9055_wdt_maps); i++)
> +		if (da9055_wdt_maps[i].user_time == timeout)
> +			break;
> +
> +	if (i == ARRAY_SIZE(da9055_wdt_maps))
> +		ret = -EINVAL;
> +	else
> +		ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B,
> +					DA9055_TWDSCALE_MASK,
> +					da9055_wdt_maps[i].reg_val <<
> +					DA9055_TWDSCALE_SHIFT);
> +	if (ret < 0)
> +		dev_err(da9055->dev,
> +			"Failed to update timescale bit, %d\n", ret);
> +
> +	wdt_dev->timeout = timeout;
> +
> +	return ret;
> +}
> +
> +static int da9055_wdt_ping(struct watchdog_device *wdt_dev)
> +{
> +	struct da9055_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
> +	struct da9055 *da9055 = driver_data->da9055;
> +	int ret;
> +
> +	/*
> +	 * We have a minimum time for watchdog window called TWDMIN. A write
> +	 * to the watchdog before this elapsed time will cause an error.
> +	 */
> +	mdelay(DA9055_TWDMIN);
> +
> +	/* Reset the watchdog timer */
> +	ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_E,
> +				DA9055_WATCHDOG_MASK, 1);
> +
> +	return ret;
> +}
> +
> +static void da9055_wdt_release_resources(struct kref *r)
> +{
> +	struct da9055_wdt_data *driver_data =
> +		container_of(r, struct da9055_wdt_data, kref);
> +
> +	kfree(driver_data);
> +}
> +
> +static void da9055_wdt_ref(struct watchdog_device *wdt_dev)
> +{
> +	struct da9055_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
> +
> +	kref_get(&driver_data->kref);
> +}
> +
> +static void da9055_wdt_unref(struct watchdog_device *wdt_dev)
> +{
> +	struct da9055_wdt_data *driver_data = watchdog_get_drvdata(wdt_dev);
> +
> +	kref_put(&driver_data->kref, da9055_wdt_release_resources);
> +}
> +
> +static int da9055_wdt_start(struct watchdog_device *wdt_dev)
> +{
> +	return da9055_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
> +}
> +
> +static int da9055_wdt_stop(struct watchdog_device *wdt_dev)
> +{
> +	return da9055_wdt_set_timeout(wdt_dev, 0);
> +}
> +
> +static struct watchdog_info da9055_wdt_info = {
> +	.options	= WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
> +	.identity	= "DA9055 Watchdog",
> +};
> +
> +static const struct watchdog_ops da9055_wdt_ops = {
> +	.owner = THIS_MODULE,
> +	.start = da9055_wdt_start,
> +	.stop = da9055_wdt_stop,
> +	.ping = da9055_wdt_ping,
> +	.set_timeout = da9055_wdt_set_timeout,
> +	.ref = da9055_wdt_ref,
> +	.unref = da9055_wdt_unref,
> +};
> +
> +static int __devinit da9055_wdt_probe(struct platform_device *pdev)
> +{
> +	struct da9055 *da9055 = dev_get_drvdata(pdev->dev.parent);
> +	struct da9055_wdt_data *driver_data;
> +	struct watchdog_device *da9055_wdt;
> +	int ret;
> +
> +	driver_data = devm_kzalloc(&pdev->dev, sizeof(*driver_data),
> +				   GFP_KERNEL);
> +	if (!driver_data) {
> +		dev_err(da9055->dev, "Failed to allocate watchdog device\n");
> +		return -ENOMEM;
> +	}
> +
> +	driver_data->da9055 = da9055;
> +
> +	da9055_wdt = &driver_data->wdt;
> +
> +	da9055_wdt->timeout = DA9055_DEF_TIMEOUT;
> +	da9055_wdt->info = &da9055_wdt_info;
> +	da9055_wdt->ops = &da9055_wdt_ops;
> +	watchdog_set_nowayout(da9055_wdt, nowayout);
> +	watchdog_set_drvdata(da9055_wdt, driver_data);
> +
> +	kref_init(&driver_data->kref);
> +
> +	ret = da9055_wdt_stop(da9055_wdt);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "Failed to stop watchdog, %d\n", ret);
> +		goto err;
> +	}
> +
> +	dev_set_drvdata(&pdev->dev, driver_data);
> +
> +	ret = watchdog_register_device(&driver_data->wdt);
> +	if (ret != 0)
> +		dev_err(da9055->dev, "watchdog_register_device() failed: %d\n",
> +			ret);
> +
> +err:
> +	return ret;
> +}
> +
> +static int __devexit da9055_wdt_remove(struct platform_device *pdev)
> +{
> +	struct da9055_wdt_data *driver_data = dev_get_drvdata(&pdev->dev);
> +
> +	watchdog_unregister_device(&driver_data->wdt);
> +	kref_put(&driver_data->kref, da9055_wdt_release_resources);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver da9055_wdt_driver = {
> +	.probe = da9055_wdt_probe,
> +	.remove = __devexit_p(da9055_wdt_remove),
> +	.driver = {
> +		.name	= "da9055-watchdog",
> +	},
> +};
> +
> +static int __init da9055_wdt_init(void)
> +{
> +	return platform_driver_register(&da9055_wdt_driver);
> +}
> +module_init(da9055_wdt_init);
> +
> +static void __exit da9055_wdt_exit(void)
> +{
> +	platform_driver_unregister(&da9055_wdt_driver);
> +}
> +module_exit(da9055_wdt_exit);
> +
> +MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
> +MODULE_DESCRIPTION("DA9055 watchdog");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:da9055-watchdog");

Re: [Patch v1 6/7] DA9055 Watchdog driver

[Wim Van Sebroeck]

Hi Ashish

> Any update on this patch?
> On Fri, 2012-09-14 at 19:03 +0530, Ashish Jangam wrote:
> > This is the Watchdog patch for the DA9055 PMIC. This patch has got
> > dependency on the DA9055 MFD core.
> > 
> > This patch is functionally tested on SMDK6410
> > 
> > Signed-off-by: David Dajun Chen <dchen@diasemi.com>
> > Signed-off-by: Ashish Jangam <ashish.jangam@kpitcummins.com>
> > ---
> >  drivers/watchdog/Kconfig      |   10 ++
> >  drivers/watchdog/Makefile     |    1 +
> >  drivers/watchdog/da9055_wdt.c |  227 +++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 238 insertions(+), 0 deletions(-)
> >  create mode 100644 drivers/watchdog/da9055_wdt.c

I'll review it tomorrow- or wednesday-evening. My first impression is that it looks OK.

Kind regards,
Wim.