diff mbox

watchdog: Add DA906x PMIC watchdog driver.

Message ID 1407832283-26444-1-git-send-email-mpa@pengutronix.de (mailing list archive)
State New, archived
Headers show

Commit Message

Markus Pargmann Aug. 12, 2014, 8:31 a.m. UTC
From: Krystian Garbaciak <krystian.garbaciak@diasemi.com>

This driver supports watchdog device inside 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>
---
 drivers/watchdog/Kconfig             |   7 ++
 drivers/watchdog/Makefile            |   1 +
 drivers/watchdog/da9063_wdt.c        | 229 +++++++++++++++++++++++++++++++++++
 include/linux/mfd/da9063/registers.h |   1 +
 4 files changed, 238 insertions(+)
 create mode 100644 drivers/watchdog/da9063_wdt.c
diff mbox

Patch

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..cd32de6c5e9d
--- /dev/null
+++ b/drivers/watchdog/da9063_wdt.c
@@ -0,0 +1,229 @@ 
+/*
+ * Watchdog driver for DA9063 PMICs.
+ *
+ * Copyright(c) 2012 Dialog Semiconductor Ltd.
+ *
+ * Author: Mariusz Wojtasik <mariusz.garbaciak@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>
+
+#define	DA9063_SUPPORTED_TIMEOUTS_STR		"2, 4, 8, 16, 32, 65, 131"
+
+/* 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 0;
+}
+
+static int _da9063_wdt_disable(struct da9063 *da9063)
+{
+	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
+			DA9063_TWDSCALE_MASK,
+			DA9063_TWDSCALE_DISABLE << DA9063_TWDSCALE_SHIFT);
+}
+
+static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
+{
+	if (regval < DA9063_TWDSCALE_MIN || regval > DA9063_TWDSCALE_MAX)
+		return -EINVAL;
+
+	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
+			DA9063_TWDSCALE_MASK, regval << DA9063_TWDSCALE_SHIFT);
+}
+
+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 = 0;
+
+	mutex_lock(&wdt->lock);
+	selector = _da9063_wdt_timeout_to_sel(wdt->wdtdev->timeout);
+	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 = 0;
+
+	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 = 0;
+
+	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 (select from: "
+				DA9063_SUPPORTED_TIMEOUTS_STR ")\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 struct watchdog_info da9063_watchdog_info = {
+	.options	= WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+	.identity	= "DA9063 Watchdog",
+};
+
+static 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 struct watchdog_device da9063_watchdog_device = {
+	.info	= &da9063_watchdog_info,
+	.ops	= &da9063_watchdog_ops,
+};
+
+static int da9063_wdt_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct da9063 *da9063 = dev_get_drvdata(pdev->dev.parent);
+	struct da9063_watchdog *wdt;
+
+	if (!da9063)
+		return -EPROBE_DEFER;
+
+	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
+	if (!wdt)
+		return -ENOMEM;
+
+	wdt->da9063 = da9063;
+	wdt->wdtdev = &da9063_watchdog_device;
+	mutex_init(&wdt->lock);
+
+	if (IS_ENABLED(CONFIG_WATCHDOG_NOWAYOUT))
+		set_bit(WDOG_NO_WAY_OUT, &wdt->wdtdev->status);
+
+	wdt->wdtdev->min_timeout = DA9063_WDT_MIN_TIMEOUT;
+	wdt->wdtdev->max_timeout = DA9063_WDT_MAX_TIMEOUT;
+	wdt->wdtdev->timeout = DA9063_WDG_TIMEOUT;
+
+	ret = watchdog_register_device(wdt->wdtdev);
+	if (ret) {
+		dev_err(da9063->dev, "da9063-watchdog registration failed (err = %d)",
+				ret);
+		return ret;
+	}
+
+	watchdog_set_drvdata(wdt->wdtdev, wdt);
+
+	return 0;
+}
+
+static int da9063_wdt_remove(struct platform_device *pdev)
+{
+	watchdog_unregister_device(&da9063_watchdog_device);
+
+	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.garbaciak@diasemi.com>");
+MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);
diff --git a/include/linux/mfd/da9063/registers.h b/include/linux/mfd/da9063/registers.h
index 09a85c699da1..cc73f5d76cc8 100644
--- a/include/linux/mfd/da9063/registers.h
+++ b/include/linux/mfd/da9063/registers.h
@@ -431,6 +431,7 @@ 
 
 /* DA9063_REG_CONTROL_D (addr=0x11) */
 #define	DA9063_TWDSCALE_MASK			0x07
+#define DA9063_TWDSCALE_SHIFT			0x00
 #define	DA9063_BLINK_FRQ_MASK			0x38
 #define		DA9063_BLINK_FRQ_OFF		0x00
 #define		DA9063_BLINK_FRQ_1S0		0x08