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path: root/drivers/watchdog/twl4030_wdt.c
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Diffstat (limited to 'drivers/watchdog/twl4030_wdt.c')
-rw-r--r--drivers/watchdog/twl4030_wdt.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/drivers/watchdog/twl4030_wdt.c b/drivers/watchdog/twl4030_wdt.c
new file mode 100644
index 000000000..2c1db6fa9
--- /dev/null
+++ b/drivers/watchdog/twl4030_wdt.c
@@ -0,0 +1,153 @@
+/*
+ * Copyright (C) Nokia Corporation
+ *
+ * Written by Timo Kokkonen <timo.t.kokkonen at nokia.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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/watchdog.h>
+#include <linux/platform_device.h>
+#include <linux/i2c/twl.h>
+
+#define TWL4030_WATCHDOG_CFG_REG_OFFS 0x3
+
+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) ")");
+
+static int twl4030_wdt_write(unsigned char val)
+{
+ return twl_i2c_write_u8(TWL_MODULE_PM_RECEIVER, val,
+ TWL4030_WATCHDOG_CFG_REG_OFFS);
+}
+
+static int twl4030_wdt_start(struct watchdog_device *wdt)
+{
+ return twl4030_wdt_write(wdt->timeout + 1);
+}
+
+static int twl4030_wdt_stop(struct watchdog_device *wdt)
+{
+ return twl4030_wdt_write(0);
+}
+
+static int twl4030_wdt_set_timeout(struct watchdog_device *wdt,
+ unsigned int timeout)
+{
+ wdt->timeout = timeout;
+ return 0;
+}
+
+static const struct watchdog_info twl4030_wdt_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
+ .identity = "TWL4030 Watchdog",
+};
+
+static const struct watchdog_ops twl4030_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = twl4030_wdt_start,
+ .stop = twl4030_wdt_stop,
+ .set_timeout = twl4030_wdt_set_timeout,
+};
+
+static int twl4030_wdt_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct watchdog_device *wdt;
+
+ wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
+ if (!wdt)
+ return -ENOMEM;
+
+ wdt->info = &twl4030_wdt_info;
+ wdt->ops = &twl4030_wdt_ops;
+ wdt->status = 0;
+ wdt->timeout = 30;
+ wdt->min_timeout = 1;
+ wdt->max_timeout = 30;
+
+ watchdog_set_nowayout(wdt, nowayout);
+ platform_set_drvdata(pdev, wdt);
+
+ twl4030_wdt_stop(wdt);
+
+ ret = watchdog_register_device(wdt);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int twl4030_wdt_remove(struct platform_device *pdev)
+{
+ struct watchdog_device *wdt = platform_get_drvdata(pdev);
+
+ watchdog_unregister_device(wdt);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct watchdog_device *wdt = platform_get_drvdata(pdev);
+ if (watchdog_active(wdt))
+ return twl4030_wdt_stop(wdt);
+
+ return 0;
+}
+
+static int twl4030_wdt_resume(struct platform_device *pdev)
+{
+ struct watchdog_device *wdt = platform_get_drvdata(pdev);
+ if (watchdog_active(wdt))
+ return twl4030_wdt_start(wdt);
+
+ return 0;
+}
+#else
+#define twl4030_wdt_suspend NULL
+#define twl4030_wdt_resume NULL
+#endif
+
+static const struct of_device_id twl_wdt_of_match[] = {
+ { .compatible = "ti,twl4030-wdt", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, twl_wdt_of_match);
+
+static struct platform_driver twl4030_wdt_driver = {
+ .probe = twl4030_wdt_probe,
+ .remove = twl4030_wdt_remove,
+ .suspend = twl4030_wdt_suspend,
+ .resume = twl4030_wdt_resume,
+ .driver = {
+ .name = "twl4030_wdt",
+ .of_match_table = twl_wdt_of_match,
+ },
+};
+
+module_platform_driver(twl4030_wdt_driver);
+
+MODULE_AUTHOR("Nokia Corporation");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:twl4030_wdt");
+