watchdog: Add DA9063 PMIC watchdog driver.
This driver supports the watchdog device inside the DA9063 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>
Acked-by: Steve Twiss <stwiss.opensource@diasemi.com>
Tested-by: Steve Twiss <stwiss.opensource@diasemi.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
diff --git a/drivers/watchdog/da9063_wdt.c b/drivers/watchdog/da9063_wdt.c
new file mode 100644
index 0000000..2cd6b2c
--- /dev/null
+++ b/drivers/watchdog/da9063_wdt.c
@@ -0,0 +1,191 @@
+/*
+ * 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 unsigned 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;
+};
+
+static unsigned int da9063_wdt_timeout_to_sel(unsigned int secs)
+{
+ unsigned int i;
+
+ for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
+ if (wdt_timeout[i] >= secs)
+ return i;
+ }
+
+ return DA9063_TWDSCALE_MAX;
+}
+
+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_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);
+ ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
+ if (ret)
+ dev_err(wdt->da9063->dev, "Watchdog failed to start (err = %d)\n",
+ ret);
+
+ return ret;
+}
+
+static int da9063_wdt_stop(struct watchdog_device *wdd)
+{
+ struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
+ int ret;
+
+ ret = regmap_update_bits(wdt->da9063->regmap, DA9063_REG_CONTROL_D,
+ DA9063_TWDSCALE_MASK, DA9063_TWDSCALE_DISABLE);
+ if (ret)
+ dev_alert(wdt->da9063->dev, "Watchdog failed to stop (err = %d)\n",
+ ret);
+
+ return ret;
+}
+
+static int da9063_wdt_ping(struct watchdog_device *wdd)
+{
+ struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
+ int ret;
+
+ ret = regmap_write(wdt->da9063->regmap, DA9063_REG_CONTROL_F,
+ DA9063_WATCHDOG);
+ if (ret)
+ dev_alert(wdt->da9063->dev, "Failed to ping the watchdog (err = %d)\n",
+ ret);
+
+ 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);
+ 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];
+
+ 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;
+
+ 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);
+
+ return ret;
+}
+
+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);