[PATCH] ARM: OMAP: Watchdog

Teach the OMAP watchdog driver about the driver model, including
defining a shutdown method (to stop the timer before kexec etc)
and suspend/resume methods (for system sleep states).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap1/devices.c

@@ -194,6 +194,39 @@ static void __init omap_init_mmc(void)
 static inline void omap_init_mmc(void) {}
 #endif
 
+#if	defined(CONFIG_OMAP16XX_WATCHDOG) || defined(CONFIG_OMAP16XX_WATCHDOG_MODULE)
+
+#define	OMAP_WDT_BASE		0xfffeb000
+
+static struct resource wdt_resources[] = {
+	{
+		.start		= OMAP_WDT_BASE,
+		.end		= OMAP_WDT_BASE + 0x4f,
+		.flags		= IORESOURCE_MEM,
+	},
+};
+
+static struct platform_device omap_wdt_device = {
+	.name	   = "omap1610_wdt",
+	.id	     = -1,
+	.dev = {
+		.release	= omap_nop_release,
+	},
+	.num_resources	= ARRAY_SIZE(wdt_resources),
+	.resource	= wdt_resources,
+};
+
+static void omap_init_wdt(void)
+{
+	(void) platform_device_register(&omap_wdt_device);
+}
+#else
+static inline void omap_init_wdt(void) {}
+#endif
+
+
+/*-------------------------------------------------------------------------*/
+
 /*
  * This gets called after board-specific INIT_MACHINE, and initializes most
  * on-chip peripherals accessible on this board (except for few like USB):
@@ -219,6 +252,7 @@ static int __init omap_init_devices(void)
 	omap_init_i2c();
 	omap_init_irda();
 	omap_init_mmc();
+	omap_init_wdt();
 
 	return 0;
 }

drivers/char/watchdog/omap1610_wdt.c

@@ -21,6 +21,9 @@
  * Copyright (c) 2004 Texas Instruments.
  *	1. Modified to support OMAP1610 32-KHz watchdog timer
  *	2. Ported to 2.6 kernel
+ *
+ * Copyright (c) 2005 David Brownell
+ *	Use the driver model and standard identifiers; handle bigger timeouts.
  */
 
 #include <linux/module.h>
@@ -35,6 +38,7 @@
 #include <linux/smp_lock.h>
 #include <linux/init.h>
 #include <linux/err.h>
+#include <linux/device.h>
 #include <linux/moduleparam.h>
 
 #include <asm/io.h>
@@ -212,12 +216,24 @@ static struct miscdevice omap_wdt_miscdev = {
 };
 
 static int __init
-omap_wdt_init(void)
+omap1610_wdt_probe(struct device *dev)
 {
-	int ret;
+	struct platform_device	*pdev = to_platform_device(dev);
+	struct resource		*res, *mem;
+	int			ret;
+
+	/* reserve static register mappings */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENOENT;
+	mem = request_mem_region(res->start, res->end - res->start + 1,
+				pdev->name);
+	if (mem == NULL)
+		return -EBUSY;
+	dev_set_drvdata(dev, mem);
 
 	omap_wdt_users = 0;
-	armwdt_ck = clk_get(NULL, "armwdt_ck");
+	armwdt_ck = clk_get(dev, "armwdt_ck");
 	if (IS_ERR(armwdt_ck)) {
 		ret = PTR_ERR(armwdt_ck);
 		armwdt_ck = NULL;
@@ -227,6 +243,7 @@ omap_wdt_init(void)
 	omap_wdt_disable();
 	omap_wdt_adjust_timeout(timer_margin);
 
+	omap_wdt_miscdev.dev = dev;
 	ret = misc_register(&omap_wdt_miscdev);
 	if (ret)
 		goto fail;
@@ -240,16 +257,74 @@ omap_wdt_init(void)
 fail:
 	if (armwdt_ck)
 		clk_put(armwdt_ck);
+	release_resource(mem);
 	return ret;
 }
 
+static void
+omap1610_wdt_shutdown(struct device *dev)
+{
+	omap_wdt_disable();
+}
+
 static void __exit
-omap_wdt_exit(void)
+omap1610_wdt_remove(struct device *dev)
 {
+	struct resource *mem = dev_get_drvdata(dev);
 	misc_deregister(&omap_wdt_miscdev);
+	release_resource(mem);
 	clk_put(armwdt_ck);
 }
 
+#ifdef	CONFIG_PM
+
+/* REVISIT ... not clear this is the best way to handle system suspend; and
+ * it's very inappropriate for selective device suspend (e.g. suspending this
+ * through sysfs rather than by stopping the watchdog daemon).  Also, this
+ * may not play well enough with NOWAYOUT...
+ */
+
+static int omap1610_wdt_suspend(struct device *dev, pm_message_t mesg, u32 level)
+{
+	if (level == SUSPEND_POWER_DOWN && omap_wdt_users)
+		omap_wdt_disable();
+	return 0;
+}
+
+static int omap1610_wdt_resume(struct device *dev, u32 level)
+{
+	if (level == RESUME_POWER_ON && omap_wdt_users) {
+		omap_wdt_enable();
+		omap_wdt_ping();
+	}
+	return 0;
+}
+
+#else
+#define	omap1610_wdt_suspend	NULL
+#define	omap1610_wdt_resume	NULL
+#endif
+
+static struct device_driver omap1610_wdt_driver = {
+	.name		= "omap1610_wdt",
+	.bus		= &platform_bus_type,
+	.probe		= omap1610_wdt_probe,
+	.shutdown	= omap1610_wdt_shutdown,
+	.remove		= __exit_p(omap1610_wdt_remove),
+	.suspend	= omap1610_wdt_suspend,
+	.resume		= omap1610_wdt_resume,
+};
+
+static int __init omap_wdt_init(void)
+{
+	return driver_register(&omap1610_wdt_driver);
+}
+
+static void __exit omap_wdt_exit(void)
+{
+	driver_unregister(&omap1610_wdt_driver);
+}
+
 module_init(omap_wdt_init);
 module_exit(omap_wdt_exit);