[PATCH v4] watchdog: Add DA906x PMIC watchdog driver.

[PATCH v4] watchdog: Add DA906x PMIC watchdog driver.

[Markus Pargmann]

From: Krystian Garbaciak <krystian.garbaciak@diasemi.com>

This driver supports the watchdog device inside the DA906x PMIC.

Signed-off-by: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
---

Notes:
    Changes in v4:
     - Fixed indentation
     - Fixed lock without unlock
     - Check for parent device and device driver data in probe(). If not present,
       this is an invalid prober initialization, return -EINVAL.
    
    Changes in v3:
     - Cleanup error handling for timeout selection and setting
     - Fix race condition due to late wdt drvdata setup
     - Remove static struct watchdog_device. It is not initialized in the probe
       function
     - Use WATCHDOG_NOWAYOUT_INIT_STATUS for the status
     - Remove 0 shift using DA9063_TWDSCALE_SHIFT

 drivers/watchdog/Kconfig      |   7 ++
 drivers/watchdog/Makefile     |   1 +
 drivers/watchdog/da9063_wdt.c | 231 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 239 insertions(+)
 create mode 100644 drivers/watchdog/da9063_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index c845527b503a..8d5c9b33552a 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -87,6 +87,13 @@ config DA9055_WATCHDOG
 	  This driver can also be built as a module.  If so, the module
 	  will be called da9055_wdt.
 
+config DA9063_WATCHDOG
+	tristate "Dialog DA9063 Watchdog"
+	depends on MFD_DA9063
+	select WATCHDOG_CORE
+	help
+	  Support for the watchdog in the DA9063 PMIC.
+
 config GPIO_WATCHDOG
 	tristate "Watchdog device controlled through GPIO-line"
 	depends on OF_GPIO
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 7b8a91ed20e7..ce4a7632d863 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -172,6 +172,7 @@ 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_DA9063_WATCHDOG) += da9063_wdt.o
 obj-$(CONFIG_GPIO_WATCHDOG)	+= gpio_wdt.o
 obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
 obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
diff --git a/drivers/watchdog/da9063_wdt.c b/drivers/watchdog/da9063_wdt.c
new file mode 100644
index 000000000000..a2d46bc55805
--- /dev/null
+++ b/drivers/watchdog/da9063_wdt.c
@@ -0,0 +1,231 @@
+/*
+ * Watchdog driver for DA9063 PMICs.
+ *
+ * Copyright(c) 2012 Dialog Semiconductor Ltd.
+ *
+ * Author: Mariusz Wojtasik <mariusz.wojtasik@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/kernel.h>
+#include <linux/module.h>
+#include <linux/watchdog.h>
+#include <linux/platform_device.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/mfd/da9063/registers.h>
+#include <linux/mfd/da9063/core.h>
+#include <linux/regmap.h>
+
+/*
+ * Watchdog selector to timeout in seconds.
+ *   0: WDT disabled;
+ *   others: timeout = 2048 ms * 2^(TWDSCALE-1).
+ */
+static const int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
+#define DA9063_TWDSCALE_DISABLE		0
+#define DA9063_TWDSCALE_MIN		1
+#define DA9063_TWDSCALE_MAX		(ARRAY_SIZE(wdt_timeout) - 1)
+#define DA9063_WDT_MIN_TIMEOUT		wdt_timeout[DA9063_TWDSCALE_MIN]
+#define DA9063_WDT_MAX_TIMEOUT		wdt_timeout[DA9063_TWDSCALE_MAX]
+#define DA9063_WDG_TIMEOUT		wdt_timeout[3]
+
+struct da9063_watchdog {
+	struct da9063 *da9063;
+	struct watchdog_device wdtdev;
+	struct mutex lock;
+};
+
+static int da9063_wdt_timeout_to_sel(int secs)
+{
+	int i;
+
+	for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
+		if (wdt_timeout[i] >= secs)
+			return i;
+	}
+
+	return -EINVAL;
+}
+
+static int da9063_wdt_disable(struct da9063 *da9063)
+{
+	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
+			DA9063_TWDSCALE_MASK,
+			DA9063_TWDSCALE_DISABLE);
+}
+
+static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
+{
+	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
+			DA9063_TWDSCALE_MASK, regval);
+}
+
+static int _da9063_wdt_kick(struct da9063 *da9063)
+{
+	return regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
+			DA9063_WATCHDOG);
+}
+
+static int da9063_wdt_start(struct watchdog_device *wdd)
+{
+	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
+	unsigned int selector;
+	int ret;
+
+	selector = da9063_wdt_timeout_to_sel(wdt->wdtdev.timeout);
+	if (selector < 0) {
+		dev_err(wdt->da9063->dev, "Timeout out of range (timeout=%d)\n",
+				wdt->wdtdev.timeout);
+		return selector;
+	}
+
+	mutex_lock(&wdt->lock);
+	ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
+	if (ret) {
+		dev_err(wdt->da9063->dev, "Watchdog failed to start (err = %d)\n",
+				ret);
+	}
+	mutex_unlock(&wdt->lock);
+
+	return ret;
+}
+
+static int da9063_wdt_stop(struct watchdog_device *wdd)
+{
+	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
+	int ret;
+
+	mutex_lock(&wdt->lock);
+	ret = da9063_wdt_disable(wdt->da9063);
+	if (ret)
+		dev_alert(wdt->da9063->dev, "Watchdog failed to stop (err = %d)\n",
+				ret);
+	mutex_unlock(&wdt->lock);
+
+	return ret;
+}
+
+static int da9063_wdt_ping(struct watchdog_device *wdd)
+{
+	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
+	int ret;
+
+	mutex_lock(&wdt->lock);
+	ret = _da9063_wdt_kick(wdt->da9063);
+	if (ret)
+		dev_alert(wdt->da9063->dev, "Failed to ping the watchdog (err = %d)\n",
+				ret);
+	mutex_unlock(&wdt->lock);
+
+	return ret;
+}
+
+static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
+		unsigned int timeout)
+{
+	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
+	unsigned int selector;
+	int ret;
+
+	selector = da9063_wdt_timeout_to_sel(timeout);
+	if (selector < 0) {
+		dev_err(wdt->da9063->dev, "Unsupported watchdog timeout, should be between 2 and 131\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&wdt->lock);
+
+	ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
+	if (ret)
+		dev_err(wdt->da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
+				ret);
+	else
+		wdd->timeout = wdt_timeout[selector];
+
+	mutex_unlock(&wdt->lock);
+
+	return ret;
+}
+
+static const struct watchdog_info da9063_watchdog_info = {
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+	.identity = "DA9063 Watchdog",
+};
+
+static const struct watchdog_ops da9063_watchdog_ops = {
+	.owner = THIS_MODULE,
+	.start = da9063_wdt_start,
+	.stop = da9063_wdt_stop,
+	.ping = da9063_wdt_ping,
+	.set_timeout = da9063_wdt_set_timeout,
+};
+
+static int da9063_wdt_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct da9063 *da9063;
+	struct da9063_watchdog *wdt;
+
+	if (!pdev->dev.parent)
+		return -EINVAL;
+
+	da9063 = dev_get_drvdata(pdev->dev.parent);
+	if (!da9063)
+		return -EINVAL;
+
+	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
+	if (!wdt)
+		return -ENOMEM;
+
+	wdt->da9063 = da9063;
+	mutex_init(&wdt->lock);
+
+	wdt->wdtdev.info = &da9063_watchdog_info;
+	wdt->wdtdev.ops = &da9063_watchdog_ops;
+	wdt->wdtdev.min_timeout = DA9063_WDT_MIN_TIMEOUT;
+	wdt->wdtdev.max_timeout = DA9063_WDT_MAX_TIMEOUT;
+	wdt->wdtdev.timeout = DA9063_WDG_TIMEOUT;
+
+	wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
+
+	watchdog_set_drvdata(&wdt->wdtdev, wdt);
+	dev_set_drvdata(&pdev->dev, wdt);
+
+	ret = watchdog_register_device(&wdt->wdtdev);
+	if (ret) {
+		dev_err(da9063->dev, "da9063-watchdog registration failed (err = %d)",
+				ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int da9063_wdt_remove(struct platform_device *pdev)
+{
+	struct da9063_watchdog *wdt = dev_get_drvdata(&pdev->dev);
+
+	watchdog_unregister_device(&wdt->wdtdev);
+
+	return 0;
+}
+
+static struct platform_driver da9063_wdt_driver = {
+	.probe = da9063_wdt_probe,
+	.remove = da9063_wdt_remove,
+	.driver = {
+		.name = DA9063_DRVNAME_WATCHDOG,
+	},
+};
+module_platform_driver(da9063_wdt_driver);
+
+MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>");
+MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);
-- 
2.0.1

[v4] watchdog: Add DA906x PMIC watchdog driver.

[Guenter Roeck]

On Sat, Aug 16, 2014 at 02:35:45PM +0200, Markus Pargmann wrote:
> From: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
> 
> This driver supports the watchdog device inside the DA906x PMIC.
> 
> Signed-off-by: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
> Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
> Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
> 
> ---
> Notes:
>     Changes in v4:
>      - Fixed indentation
>      - Fixed lock without unlock
>      - Check for parent device and device driver data in probe(). If not present,
>        this is an invalid prober initialization, return -EINVAL.
>     
>     Changes in v3:
>      - Cleanup error handling for timeout selection and setting
>      - Fix race condition due to late wdt drvdata setup
>      - Remove static struct watchdog_device. It is not initialized in the probe
>        function
>      - Use WATCHDOG_NOWAYOUT_INIT_STATUS for the status
>      - Remove 0 shift using DA9063_TWDSCALE_SHIFT
> 
>  drivers/watchdog/Kconfig      |   7 ++
>  drivers/watchdog/Makefile     |   1 +
>  drivers/watchdog/da9063_wdt.c | 231 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 239 insertions(+)
>  create mode 100644 drivers/watchdog/da9063_wdt.c
> 
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index c845527b503a..8d5c9b33552a 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -87,6 +87,13 @@ config DA9055_WATCHDOG
>  	  This driver can also be built as a module.  If so, the module
>  	  will be called da9055_wdt.
>  
> +config DA9063_WATCHDOG
> +	tristate "Dialog DA9063 Watchdog"
> +	depends on MFD_DA9063
> +	select WATCHDOG_CORE
> +	help
> +	  Support for the watchdog in the DA9063 PMIC.
> +
Please add a note such as above, listing the module name.

>  config GPIO_WATCHDOG
>  	tristate "Watchdog device controlled through GPIO-line"
>  	depends on OF_GPIO
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 7b8a91ed20e7..ce4a7632d863 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -172,6 +172,7 @@ 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_DA9063_WATCHDOG) += da9063_wdt.o
>  obj-$(CONFIG_GPIO_WATCHDOG)	+= gpio_wdt.o
>  obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
>  obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
> diff --git a/drivers/watchdog/da9063_wdt.c b/drivers/watchdog/da9063_wdt.c
> new file mode 100644
> index 000000000000..a2d46bc55805
> --- /dev/null
> +++ b/drivers/watchdog/da9063_wdt.c
> @@ -0,0 +1,231 @@
> +/*
> + * Watchdog driver for DA9063 PMICs.
> + *
> + * Copyright(c) 2012 Dialog Semiconductor Ltd.
> + *
> + * Author: Mariusz Wojtasik <mariusz.wojtasik@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/kernel.h>
> +#include <linux/module.h>
> +#include <linux/watchdog.h>
> +#include <linux/platform_device.h>
> +#include <linux/uaccess.h>
> +#include <linux/slab.h>
> +#include <linux/delay.h>
> +#include <linux/mfd/da9063/registers.h>
> +#include <linux/mfd/da9063/core.h>
> +#include <linux/regmap.h>
> +
> +/*
> + * Watchdog selector to timeout in seconds.
> + *   0: WDT disabled;
> + *   others: timeout = 2048 ms * 2^(TWDSCALE-1).
> + */
> +static const int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
> +#define DA9063_TWDSCALE_DISABLE		0
> +#define DA9063_TWDSCALE_MIN		1
> +#define DA9063_TWDSCALE_MAX		(ARRAY_SIZE(wdt_timeout) - 1)
> +#define DA9063_WDT_MIN_TIMEOUT		wdt_timeout[DA9063_TWDSCALE_MIN]
> +#define DA9063_WDT_MAX_TIMEOUT		wdt_timeout[DA9063_TWDSCALE_MAX]
> +#define DA9063_WDG_TIMEOUT		wdt_timeout[3]
> +
> +struct da9063_watchdog {
> +	struct da9063 *da9063;
> +	struct watchdog_device wdtdev;
> +	struct mutex lock;
> +};
> +
> +static int da9063_wdt_timeout_to_sel(int secs)
> +{
> +	int i;
> +
> +	for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {

When building with W=1, gcc complains about this line. Would be great if you can
have a look and fix it.

> +		if (wdt_timeout[i] >= secs)
> +			return i;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int da9063_wdt_disable(struct da9063 *da9063)
> +{
> +	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
> +			DA9063_TWDSCALE_MASK,
> +			DA9063_TWDSCALE_DISABLE);
> +}
> +
> +static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
> +{
> +	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
> +			DA9063_TWDSCALE_MASK, regval);
> +}
> +
> +static int _da9063_wdt_kick(struct da9063 *da9063)
> +{
> +	return regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
> +			DA9063_WATCHDOG);
> +}
> +
> +static int da9063_wdt_start(struct watchdog_device *wdd)
> +{
> +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> +	unsigned int selector;
> +	int ret;
> +
> +	selector = da9063_wdt_timeout_to_sel(wdt->wdtdev.timeout);
> +	if (selector < 0) {

selector has to be an int for this to work. Building the driver with W=1 reports
it, btw.

> +		dev_err(wdt->da9063->dev, "Timeout out of range (timeout=%d)\n",
> +				wdt->wdtdev.timeout);
> +		return selector;
> +	}
> +
> +	mutex_lock(&wdt->lock);
> +	ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
> +	if (ret) {
> +		dev_err(wdt->da9063->dev, "Watchdog failed to start (err = %d)\n",
> +				ret);
> +	}
> +	mutex_unlock(&wdt->lock);
> +
> +	return ret;
> +}
> +
> +static int da9063_wdt_stop(struct watchdog_device *wdd)
> +{
> +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> +	int ret;
> +
> +	mutex_lock(&wdt->lock);
> +	ret = da9063_wdt_disable(wdt->da9063);
> +	if (ret)
> +		dev_alert(wdt->da9063->dev, "Watchdog failed to stop (err = %d)\n",
> +				ret);

You have a number of places where the continuation line _on purpose_
does not align to te opening '('. I would understand it if your indentation
rules were in any way consistent, but I don't see that either.
Ok, I can see that you dislike the rule that continuation lines should be
aligned to '(', but to misalign even when the '(' matches a tab position doesn't
really make any sense.

> +	mutex_unlock(&wdt->lock);
> +
> +	return ret;
> +}
> +
> +static int da9063_wdt_ping(struct watchdog_device *wdd)
> +{
> +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> +	int ret;
> +
> +	mutex_lock(&wdt->lock);
> +	ret = _da9063_wdt_kick(wdt->da9063);
> +	if (ret)
> +		dev_alert(wdt->da9063->dev, "Failed to ping the watchdog (err = %d)\n",
> +				ret);
> +	mutex_unlock(&wdt->lock);
> +
> +	return ret;
> +}
> +
> +static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
> +		unsigned int timeout)
> +{
> +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> +	unsigned int selector;
> +	int ret;
> +
> +	selector = da9063_wdt_timeout_to_sel(timeout);
> +	if (selector < 0) {

selector must be an int for this to work.

> +		dev_err(wdt->da9063->dev, "Unsupported watchdog timeout, should be between 2 and 131\n");

Please use a continuation line here.

> +		return -EINVAL;
> +	}
> +
> +	mutex_lock(&wdt->lock);
> +
> +	ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
> +	if (ret)
> +		dev_err(wdt->da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
> +				ret);
> +	else
> +		wdd->timeout = wdt_timeout[selector];
> +
> +	mutex_unlock(&wdt->lock);
> +
> +	return ret;
> +}
> +
> +static const struct watchdog_info da9063_watchdog_info = {
> +	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
> +	.identity = "DA9063 Watchdog",
> +};
> +
> +static const struct watchdog_ops da9063_watchdog_ops = {
> +	.owner = THIS_MODULE,
> +	.start = da9063_wdt_start,
> +	.stop = da9063_wdt_stop,
> +	.ping = da9063_wdt_ping,
> +	.set_timeout = da9063_wdt_set_timeout,
> +};
> +
> +static int da9063_wdt_probe(struct platform_device *pdev)
> +{
> +	int ret;
> +	struct da9063 *da9063;
> +	struct da9063_watchdog *wdt;
> +
> +	if (!pdev->dev.parent)
> +		return -EINVAL;
> +
> +	da9063 = dev_get_drvdata(pdev->dev.parent);
> +	if (!da9063)
> +		return -EINVAL;
> +
> +	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
> +	if (!wdt)
> +		return -ENOMEM;
> +
> +	wdt->da9063 = da9063;
> +	mutex_init(&wdt->lock);
> +
> +	wdt->wdtdev.info = &da9063_watchdog_info;
> +	wdt->wdtdev.ops = &da9063_watchdog_ops;
> +	wdt->wdtdev.min_timeout = DA9063_WDT_MIN_TIMEOUT;
> +	wdt->wdtdev.max_timeout = DA9063_WDT_MAX_TIMEOUT;
> +	wdt->wdtdev.timeout = DA9063_WDG_TIMEOUT;
> +
> +	wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
> +
> +	watchdog_set_drvdata(&wdt->wdtdev, wdt);
> +	dev_set_drvdata(&pdev->dev, wdt);
> +
> +	ret = watchdog_register_device(&wdt->wdtdev);
> +	if (ret) {
> +		dev_err(da9063->dev, "da9063-watchdog registration failed (err = %d)",
> +				ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int da9063_wdt_remove(struct platform_device *pdev)
> +{
> +	struct da9063_watchdog *wdt = dev_get_drvdata(&pdev->dev);
> +
> +	watchdog_unregister_device(&wdt->wdtdev);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver da9063_wdt_driver = {
> +	.probe = da9063_wdt_probe,
> +	.remove = da9063_wdt_remove,
> +	.driver = {
> +		.name = DA9063_DRVNAME_WATCHDOG,
> +	},
> +};
> +module_platform_driver(da9063_wdt_driver);
> +
> +MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>");
> +MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);

[v4] watchdog: Add DA906x PMIC watchdog driver.

[Markus Pargmann]

Hi,

On Wed, Aug 20, 2014 at 07:43:22AM -0700, Guenter Roeck wrote:
> On Sat, Aug 16, 2014 at 02:35:45PM +0200, Markus Pargmann wrote:
> > From: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
> > 
> > This driver supports the watchdog device inside the DA906x PMIC.
> > 
> > Signed-off-by: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
> > Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
> > Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
> > 
> > ---
> > Notes:
> >     Changes in v4:
> >      - Fixed indentation
> >      - Fixed lock without unlock
> >      - Check for parent device and device driver data in probe(). If not present,
> >        this is an invalid prober initialization, return -EINVAL.
> >     
> >     Changes in v3:
> >      - Cleanup error handling for timeout selection and setting
> >      - Fix race condition due to late wdt drvdata setup
> >      - Remove static struct watchdog_device. It is not initialized in the probe
> >        function
> >      - Use WATCHDOG_NOWAYOUT_INIT_STATUS for the status
> >      - Remove 0 shift using DA9063_TWDSCALE_SHIFT
> > 
> >  drivers/watchdog/Kconfig      |   7 ++
> >  drivers/watchdog/Makefile     |   1 +
> >  drivers/watchdog/da9063_wdt.c | 231 ++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 239 insertions(+)
> >  create mode 100644 drivers/watchdog/da9063_wdt.c
> > 
> > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> > index c845527b503a..8d5c9b33552a 100644
> > --- a/drivers/watchdog/Kconfig
> > +++ b/drivers/watchdog/Kconfig
> > @@ -87,6 +87,13 @@ config DA9055_WATCHDOG
> >  	  This driver can also be built as a module.  If so, the module
> >  	  will be called da9055_wdt.
> >  
> > +config DA9063_WATCHDOG
> > +	tristate "Dialog DA9063 Watchdog"
> > +	depends on MFD_DA9063
> > +	select WATCHDOG_CORE
> > +	help
> > +	  Support for the watchdog in the DA9063 PMIC.
> > +
> Please add a note such as above, listing the module name.

Added such a note.

> 
> >  config GPIO_WATCHDOG
> >  	tristate "Watchdog device controlled through GPIO-line"
> >  	depends on OF_GPIO
> > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> > index 7b8a91ed20e7..ce4a7632d863 100644
> > --- a/drivers/watchdog/Makefile
> > +++ b/drivers/watchdog/Makefile
> > @@ -172,6 +172,7 @@ 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_DA9063_WATCHDOG) += da9063_wdt.o
> >  obj-$(CONFIG_GPIO_WATCHDOG)	+= gpio_wdt.o
> >  obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
> >  obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
> > diff --git a/drivers/watchdog/da9063_wdt.c b/drivers/watchdog/da9063_wdt.c
> > new file mode 100644
> > index 000000000000..a2d46bc55805
> > --- /dev/null
> > +++ b/drivers/watchdog/da9063_wdt.c
> > @@ -0,0 +1,231 @@
> > +/*
> > + * Watchdog driver for DA9063 PMICs.
> > + *
> > + * Copyright(c) 2012 Dialog Semiconductor Ltd.
> > + *
> > + * Author: Mariusz Wojtasik <mariusz.wojtasik@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/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/watchdog.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/uaccess.h>
> > +#include <linux/slab.h>
> > +#include <linux/delay.h>
> > +#include <linux/mfd/da9063/registers.h>
> > +#include <linux/mfd/da9063/core.h>
> > +#include <linux/regmap.h>
> > +
> > +/*
> > + * Watchdog selector to timeout in seconds.
> > + *   0: WDT disabled;
> > + *   others: timeout = 2048 ms * 2^(TWDSCALE-1).
> > + */
> > +static const int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
> > +#define DA9063_TWDSCALE_DISABLE		0
> > +#define DA9063_TWDSCALE_MIN		1
> > +#define DA9063_TWDSCALE_MAX		(ARRAY_SIZE(wdt_timeout) - 1)
> > +#define DA9063_WDT_MIN_TIMEOUT		wdt_timeout[DA9063_TWDSCALE_MIN]
> > +#define DA9063_WDT_MAX_TIMEOUT		wdt_timeout[DA9063_TWDSCALE_MAX]
> > +#define DA9063_WDG_TIMEOUT		wdt_timeout[3]
> > +
> > +struct da9063_watchdog {
> > +	struct da9063 *da9063;
> > +	struct watchdog_device wdtdev;
> > +	struct mutex lock;
> > +};
> > +
> > +static int da9063_wdt_timeout_to_sel(int secs)
> > +{
> > +	int i;
> > +
> > +	for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
> 
> When building with W=1, gcc complains about this line. Would be great if you can
> have a look and fix it.

I just compiled with W=1, it doesn't complain here about this line.
Could you give me the warning?

> 
> > +		if (wdt_timeout[i] >= secs)
> > +			return i;
> > +	}
> > +
> > +	return -EINVAL;
> > +}
> > +
> > +static int da9063_wdt_disable(struct da9063 *da9063)
> > +{
> > +	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
> > +			DA9063_TWDSCALE_MASK,
> > +			DA9063_TWDSCALE_DISABLE);
> > +}
> > +
> > +static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
> > +{
> > +	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
> > +			DA9063_TWDSCALE_MASK, regval);
> > +}
> > +
> > +static int _da9063_wdt_kick(struct da9063 *da9063)
> > +{
> > +	return regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
> > +			DA9063_WATCHDOG);
> > +}
> > +
> > +static int da9063_wdt_start(struct watchdog_device *wdd)
> > +{
> > +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> > +	unsigned int selector;
> > +	int ret;
> > +
> > +	selector = da9063_wdt_timeout_to_sel(wdt->wdtdev.timeout);
> > +	if (selector < 0) {
> 
> selector has to be an int for this to work. Building the driver with W=1 reports
> it, btw.

Yes, thanks, I changed both selector variables to int.

> 
> > +		dev_err(wdt->da9063->dev, "Timeout out of range (timeout=%d)\n",
> > +				wdt->wdtdev.timeout);
> > +		return selector;
> > +	}
> > +
> > +	mutex_lock(&wdt->lock);
> > +	ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
> > +	if (ret) {
> > +		dev_err(wdt->da9063->dev, "Watchdog failed to start (err = %d)\n",
> > +				ret);
> > +	}
> > +	mutex_unlock(&wdt->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int da9063_wdt_stop(struct watchdog_device *wdd)
> > +{
> > +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> > +	int ret;
> > +
> > +	mutex_lock(&wdt->lock);
> > +	ret = da9063_wdt_disable(wdt->da9063);
> > +	if (ret)
> > +		dev_alert(wdt->da9063->dev, "Watchdog failed to stop (err = %d)\n",
> > +				ret);
> 
> You have a number of places where the continuation line _on purpose_
> does not align to te opening '('. I would understand it if your indentation
> rules were in any way consistent, but I don't see that either.
> Ok, I can see that you dislike the rule that continuation lines should be
> aligned to '(', but to misalign even when the '(' matches a tab position doesn't
> really make any sense.

My indentation rules are consistent, otherwise I made a mistake. I
always indent two tabs after an opening bracket when breaking long
lines. Also I can't find any specific rules about how to break long
lines in the coding style document.

> 
> > +	mutex_unlock(&wdt->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int da9063_wdt_ping(struct watchdog_device *wdd)
> > +{
> > +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> > +	int ret;
> > +
> > +	mutex_lock(&wdt->lock);
> > +	ret = _da9063_wdt_kick(wdt->da9063);
> > +	if (ret)
> > +		dev_alert(wdt->da9063->dev, "Failed to ping the watchdog (err = %d)\n",
> > +				ret);
> > +	mutex_unlock(&wdt->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
> > +		unsigned int timeout)
> > +{
> > +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> > +	unsigned int selector;
> > +	int ret;
> > +
> > +	selector = da9063_wdt_timeout_to_sel(timeout);
> > +	if (selector < 0) {
> 
> selector must be an int for this to work.
> 
> > +		dev_err(wdt->da9063->dev, "Unsupported watchdog timeout, should be between 2 and 131\n");
> 
> Please use a continuation line here.

Ok.

Thank you,

Markus

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
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[v4] watchdog: Add DA906x PMIC watchdog driver.

[Guenter Roeck]

On Thu, Aug 21, 2014 at 08:15:25AM +0200, Markus Pargmann wrote:
> Hi,
> 
...
> > > +static int da9063_wdt_timeout_to_sel(int secs)
> > > +{
> > > +	int i;
> > > +
> > > +	for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
> > 
> > When building with W=1, gcc complains about this line. Would be great if you can
> > have a look and fix it.
> 
> I just compiled with W=1, it doesn't complain here about this line.
> Could you give me the warning?
> 
drivers/watchdog/da9063_wdt.c: In function 'da9063_wdt_timeout_to_sel':
drivers/watchdog/da9063_wdt.c:48:34: warning: comparison between signed and
unsigned integer expressions [-Wsign-compare]

This is with arm-poky-linux-gnueabi-gcc (GCC) 4.7.2.

> > > +static int da9063_wdt_stop(struct watchdog_device *wdd)
> > > +{
> > > +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> > > +	int ret;
> > > +
> > > +	mutex_lock(&wdt->lock);
> > > +	ret = da9063_wdt_disable(wdt->da9063);
> > > +	if (ret)
> > > +		dev_alert(wdt->da9063->dev, "Watchdog failed to stop (err = %d)\n",
> > > +				ret);
> > 
> > You have a number of places where the continuation line _on purpose_
> > does not align to te opening '('. I would understand it if your indentation
> > rules were in any way consistent, but I don't see that either.
> > Ok, I can see that you dislike the rule that continuation lines should be
> > aligned to '(', but to misalign even when the '(' matches a tab position doesn't
> > really make any sense.
> 
> My indentation rules are consistent, otherwise I made a mistake. I
> always indent two tabs after an opening bracket when breaking long
> lines. Also I can't find any specific rules about how to break long
> lines in the coding style document.
> 
Hmm, I thought this was an official CodingStyle rule. Guess it is just a
checkpatch rule. Oh well.

Guenter

[PATCH v4] watchdog: Add DA906x PMIC watchdog driver.

[Opensource [Steve Twiss]]

On 16 August 2014 13:36, Markus Pargmann [mailto:mpa at pengutronix.de] wrote:

> Subject: [PATCH v4] watchdog: Add DA906x PMIC watchdog driver.

Hi Markus,

> 
> From: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
> 
> This driver supports the watchdog device inside the DA906x PMIC.
> 

There is only DA9063 , in this case there is no "x". Thanks.

[...]

> +
> +/*
> + * Watchdog selector to timeout in seconds.
> + *   0: WDT disabled;
> + *   others: timeout = 2048 ms * 2^(TWDSCALE-1).
> + */
> +static const int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };

This table is just an approximation of the real times provided by the PMIC. 

The first three bits in the CONTROL_D register at 0x11 define a scaling value
for the nominal maximum time TWDMAX. The 7 values specifying the timeout
of the watchdog are:

001 = 1 = 1x = 2048ms 
010 = 2 = 2x = 4096ms
011 = 3 = 4x = 8192ms
100 = 4 = 8x = 16384ms
101 = 5 = 16x = 32768ms
110 = 6 = 32x = 65536ms
111 = 7 = 64x = 131072ms

 [...]

> +
> +static int da9063_wdt_disable(struct da9063 *da9063)
> +{
> +	return regmap_update_bits(da9063->regmap,
> DA9063_REG_CONTROL_D,
> +			DA9063_TWDSCALE_MASK,
> +			DA9063_TWDSCALE_DISABLE);
> +}
> +
> +static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int
> regval)
> +{
> +	return regmap_update_bits(da9063->regmap,
> DA9063_REG_CONTROL_D,
> +			DA9063_TWDSCALE_MASK, regval);
> +}
> +
> +static int _da9063_wdt_kick(struct da9063 *da9063)
> +{
> +	return regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
> +			DA9063_WATCHDOG);
> +}
> +

The _da9063_wdt_kick() and da9063_wdt_disable() functions are only used once
throughout the code -- in the watchdog_ops functions da9063_wdt_ping() and
da9063_wdt_stop() respectively. 
Since these are just simple regmap calls, could they be added at those places
directly and therefore remove the function calls?

[...]

> +static int da9063_wdt_start(struct watchdog_device *wdd)
> +{
> +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> +	unsigned int selector;
> +	int ret;
> +
> +	selector = da9063_wdt_timeout_to_sel(wdt->wdtdev.timeout);
> +	if (selector < 0) {

Unsigned if < 0

 [...]

> +static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
> +		unsigned int timeout)
> +{
> +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> +	unsigned int selector;
> +	int ret;
> +
> +	selector = da9063_wdt_timeout_to_sel(timeout);
> +	if (selector < 0) {

And again

Regards,
Steve

[v4] watchdog: Add DA906x PMIC watchdog driver.

[Markus Pargmann]

Hi,

On Thu, Aug 21, 2014 at 07:19:59AM -0700, Guenter Roeck wrote:
> On Thu, Aug 21, 2014 at 08:15:25AM +0200, Markus Pargmann wrote:
> > Hi,
> > 
> ...
> > > > +static int da9063_wdt_timeout_to_sel(int secs)
> > > > +{
> > > > +	int i;
> > > > +
> > > > +	for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
> > > 
> > > When building with W=1, gcc complains about this line. Would be great if you can
> > > have a look and fix it.
> > 
> > I just compiled with W=1, it doesn't complain here about this line.
> > Could you give me the warning?
> > 
> drivers/watchdog/da9063_wdt.c: In function 'da9063_wdt_timeout_to_sel':
> drivers/watchdog/da9063_wdt.c:48:34: warning: comparison between signed and
> unsigned integer expressions [-Wsign-compare]
> 
> This is with arm-poky-linux-gnueabi-gcc (GCC) 4.7.2.

Thanks, I am using gcc 4.8.3. I replaced the used 'int' type by 'unsigend
int', that should fix it.

Best regards,

Markus

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
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[PATCH v4] watchdog: Add DA906x PMIC watchdog driver.

[Markus Pargmann]

Hi Steve,

On Fri, Aug 22, 2014 at 03:47:48PM +0000, Opensource [Steve Twiss] wrote:
> On 16 August 2014 13:36, Markus Pargmann [mailto:mpa at pengutronix.de] wrote:
> 
> > Subject: [PATCH v4] watchdog: Add DA906x PMIC watchdog driver.
> 
> Hi Markus,
> 
> > 
> > From: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
> > 
> > This driver supports the watchdog device inside the DA906x PMIC.
> > 
> 
> There is only DA9063 , in this case there is no "x". Thanks.

Thanks, fixed in the commit message.

> 
> [...]
> 
> > +
> > +/*
> > + * Watchdog selector to timeout in seconds.
> > + *   0: WDT disabled;
> > + *   others: timeout = 2048 ms * 2^(TWDSCALE-1).
> > + */
> > +static const int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
> 
> This table is just an approximation of the real times provided by the PMIC. 
> 
> The first three bits in the CONTROL_D register at 0x11 define a scaling value
> for the nominal maximum time TWDMAX. The 7 values specifying the timeout
> of the watchdog are:
> 
> 001 = 1 = 1x = 2048ms 
> 010 = 2 = 2x = 4096ms
> 011 = 3 = 4x = 8192ms
> 100 = 4 = 8x = 16384ms
> 101 = 5 = 16x = 32768ms
> 110 = 6 = 32x = 65536ms
> 111 = 7 = 64x = 131072ms

Thanks. So the 7 values are good approximations for the real values
right?

> 
>  [...]
> 
> > +
> > +static int da9063_wdt_disable(struct da9063 *da9063)
> > +{
> > +	return regmap_update_bits(da9063->regmap,
> > DA9063_REG_CONTROL_D,
> > +			DA9063_TWDSCALE_MASK,
> > +			DA9063_TWDSCALE_DISABLE);
> > +}
> > +
> > +static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int
> > regval)
> > +{
> > +	return regmap_update_bits(da9063->regmap,
> > DA9063_REG_CONTROL_D,
> > +			DA9063_TWDSCALE_MASK, regval);
> > +}
> > +
> > +static int _da9063_wdt_kick(struct da9063 *da9063)
> > +{
> > +	return regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
> > +			DA9063_WATCHDOG);
> > +}
> > +
> 
> The _da9063_wdt_kick() and da9063_wdt_disable() functions are only used once
> throughout the code -- in the watchdog_ops functions da9063_wdt_ping() and
> da9063_wdt_stop() respectively. 
> Since these are just simple regmap calls, could they be added at those places
> directly and therefore remove the function calls?

Thanks, I removed those functions and included the regmap function calls
directly as they are already well described by the functions from which
they are called.

> 
> [...]
> 
> > +static int da9063_wdt_start(struct watchdog_device *wdd)
> > +{
> > +	struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> > +	unsigned int selector;
> > +	int ret;
> > +
> > +	selector = da9063_wdt_timeout_to_sel(wdt->wdtdev.timeout);
> > +	if (selector < 0) {
> 
> Unsigned if < 0

That was already fixed for the next version.

Thanks,

Markus

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
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