[WATCHDOG] pnx4008: add watchdog support

Add watchdog support for Philips PNX4008 ARM board inlined.

Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

3 files changed, 365 insertions, 0 deletions

diff --git a/drivers/char/watchdog/Kconfig b/drivers/char/watchdog/Kconfig
index 77ab7e0..06f3fa2 100644
--- a/drivers/char/watchdog/Kconfig
+++ b/drivers/char/watchdog/Kconfig
@@ -172,6 +172,17 @@ config OMAP_WATCHDOG
 	  Support for TI OMAP1610/OMAP1710/OMAP2420 watchdog.  Say 'Y' here to
 	  enable the OMAP1610/OMAP1710 watchdog timer.
 
+config PNX4008_WATCHDOG
+	tristate "PNX4008 Watchdog"
+	depends on WATCHDOG && ARCH_PNX4008
+	help
+	  Say Y here if to include support for the watchdog timer
+	  in the PNX4008 processor.
+	  This driver can be built as a module by choosing M. The module
+	  will be called pnx4008_wdt.
+
+	  Say N if you are unsure.
+
 # X86 (i386 + ia64 + x86_64) Architecture
 
 config ACQUIRE_WDT
diff --git a/drivers/char/watchdog/Makefile b/drivers/char/watchdog/Makefile
index 5099f8b..6ffca7c 100644
--- a/drivers/char/watchdog/Makefile
+++ b/drivers/char/watchdog/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_S3C2410_WATCHDOG) += s3c2410_wdt.o
 obj-$(CONFIG_SA1100_WATCHDOG) += sa1100_wdt.o
 obj-$(CONFIG_MPCORE_WATCHDOG) += mpcore_wdt.o
 obj-$(CONFIG_EP93XX_WATCHDOG) += ep93xx_wdt.o
+obj-$(CONFIG_PNX4008_WATCHDOG) += pnx4008_wdt.o
 
 # X86 (i386 + ia64 + x86_64) Architecture
 obj-$(CONFIG_ACQUIRE_WDT) += acquirewdt.o
diff --git a/drivers/char/watchdog/pnx4008_wdt.c b/drivers/char/watchdog/pnx4008_wdt.c
new file mode 100644
index 0000000..7ae2d08
--- /dev/null
+++ b/drivers/char/watchdog/pnx4008_wdt.c
@@ -0,0 +1,353 @@
+/*
+ * drivers/char/watchdog/pnx4008_wdt.c
+ *
+ * Watchdog driver for PNX4008 board
+ *
+ * Authors: Dmitry Chigirev <source@mvista.com>,
+ * 	    Vitaly Wool <vitalywool@gmail.com>
+ * Based on sa1100 driver,
+ * Copyright (C) 2000 Oleg Drokin <green@crimea.edu>
+ *
+ * 2005-2006 (c) MontaVista Software, Inc. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/ioport.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+
+#include <asm/hardware.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+
+#define MODULE_NAME "PNX4008-WDT: "
+
+/* WatchDog Timer - Chapter 23 Page 207 */
+
+#define DEFAULT_HEARTBEAT 19
+#define MAX_HEARTBEAT     60
+
+/* Watchdog timer register set definition */
+#define WDTIM_INT(p)     ((p) + 0x0)
+#define WDTIM_CTRL(p)    ((p) + 0x4)
+#define WDTIM_COUNTER(p) ((p) + 0x8)
+#define WDTIM_MCTRL(p)   ((p) + 0xC)
+#define WDTIM_MATCH0(p)  ((p) + 0x10)
+#define WDTIM_EMR(p)     ((p) + 0x14)
+#define WDTIM_PULSE(p)   ((p) + 0x18)
+#define WDTIM_RES(p)     ((p) + 0x1C)
+
+/* WDTIM_INT bit definitions */
+#define MATCH_INT      1
+
+/* WDTIM_CTRL bit definitions */
+#define COUNT_ENAB     1
+#define RESET_COUNT    (1<<1)
+#define DEBUG_EN       (1<<2)
+
+/* WDTIM_MCTRL bit definitions */
+#define MR0_INT        1
+#undef  RESET_COUNT0
+#define RESET_COUNT0   (1<<2)
+#define STOP_COUNT0    (1<<2)
+#define M_RES1         (1<<3)
+#define M_RES2         (1<<4)
+#define RESFRC1        (1<<5)
+#define RESFRC2        (1<<6)
+
+/* WDTIM_EMR bit definitions */
+#define EXT_MATCH0      1
+#define MATCH_OUTPUT_HIGH (2<<4)	/*a MATCH_CTRL setting */
+
+/* WDTIM_RES bit definitions */
+#define WDOG_RESET      1	/* read only */
+
+#define WDOG_COUNTER_RATE 13000000	/*the counter clock is 13 MHz fixed */
+
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+static int nowayout = 1;
+#else
+static int nowayout = 0;
+#endif
+static int heartbeat = DEFAULT_HEARTBEAT;
+
+static unsigned long wdt_status;
+#define WDT_IN_USE        0
+#define WDT_OK_TO_CLOSE   1
+#define WDT_REGION_INITED 2
+#define WDT_DEVICE_INITED 3
+
+static unsigned long boot_status;
+
+static struct resource	*wdt_mem;
+static void __iomem	*wdt_base;
+struct clk		*wdt_clk;
+
+static void wdt_enable(void)
+{
+	if (wdt_clk)
+		clk_set_rate(wdt_clk, 1);
+
+	/* stop counter, initiate counter reset */
+	__raw_writel(RESET_COUNT, WDTIM_CTRL(wdt_base));
+	/*wait for reset to complete. 100% guarantee event */
+	while (__raw_readl(WDTIM_COUNTER(wdt_base)));
+	/* internal and external reset, stop after that */
+	__raw_writel(M_RES2 | STOP_COUNT0 | RESET_COUNT0,
+		WDTIM_MCTRL(wdt_base));
+	/* configure match output */
+	__raw_writel(MATCH_OUTPUT_HIGH, WDTIM_EMR(wdt_base));
+	/* clear interrupt, just in case */
+	__raw_writel(MATCH_INT, WDTIM_INT(wdt_base));
+	/* the longest pulse period 65541/(13*10^6) seconds ~ 5 ms. */
+	__raw_writel(0xFFFF, WDTIM_PULSE(wdt_base));
+	__raw_writel(heartbeat * WDOG_COUNTER_RATE, WDTIM_MATCH0(wdt_base));
+	/*enable counter, stop when debugger active */
+	__raw_writel(COUNT_ENAB | DEBUG_EN, WDTIM_CTRL(wdt_base));
+}
+
+static void wdt_disable(void)
+{
+	__raw_writel(0, WDTIM_CTRL(wdt_base));	/*stop counter */
+	if (wdt_clk)
+		clk_set_rate(wdt_clk, 0);
+}
+
+static int pnx4008_wdt_open(struct inode *inode, struct file *file)
+{
+	if (test_and_set_bit(WDT_IN_USE, &wdt_status))
+		return -EBUSY;
+
+	clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
+
+	wdt_enable();
+
+	return nonseekable_open(inode, file);
+}
+
+static ssize_t
+pnx4008_wdt_write(struct file *file, const char *data, size_t len,
+		  loff_t * ppos)
+{
+	/*  Can't seek (pwrite) on this device  */
+	if (ppos != &file->f_pos)
+		return -ESPIPE;
+
+	if (len) {
+		if (!nowayout) {
+			size_t i;
+
+			clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
+
+			for (i = 0; i != len; i++) {
+				char c;
+
+				if (get_user(c, data + i))
+					return -EFAULT;
+				if (c == 'V')
+					set_bit(WDT_OK_TO_CLOSE, &wdt_status);
+			}
+		}
+		wdt_enable();
+	}
+
+	return len;
+}
+
+static struct watchdog_info ident = {
+	.options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE |
+	    WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+	.identity = "PNX4008 Watchdog",
+};
+
+static int
+pnx4008_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+		  unsigned long arg)
+{
+	int ret = -ENOIOCTLCMD;
+	int time;
+
+	switch (cmd) {
+	case WDIOC_GETSUPPORT:
+		ret = copy_to_user((struct watchdog_info *)arg, &ident,
+				   sizeof(ident)) ? -EFAULT : 0;
+		break;
+
+	case WDIOC_GETSTATUS:
+		ret = put_user(0, (int *)arg);
+		break;
+
+	case WDIOC_GETBOOTSTATUS:
+		ret = put_user(boot_status, (int *)arg);
+		break;
+
+	case WDIOC_SETTIMEOUT:
+		ret = get_user(time, (int *)arg);
+		if (ret)
+			break;
+
+		if (time <= 0 || time > MAX_HEARTBEAT) {
+			ret = -EINVAL;
+			break;
+		}
+
+		heartbeat = time;
+		wdt_enable();
+		/* Fall through */
+
+	case WDIOC_GETTIMEOUT:
+		ret = put_user(heartbeat, (int *)arg);
+		break;
+
+	case WDIOC_KEEPALIVE:
+		wdt_enable();
+		ret = 0;
+		break;
+	}
+	return ret;
+}
+
+static int pnx4008_wdt_release(struct inode *inode, struct file *file)
+{
+	if (!test_bit(WDT_OK_TO_CLOSE, &wdt_status))
+		printk(KERN_WARNING "WATCHDOG: Device closed unexpectdly\n");
+
+	wdt_disable();
+	clear_bit(WDT_IN_USE, &wdt_status);
+	clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
+
+	return 0;
+}
+
+static struct file_operations pnx4008_wdt_fops = {
+	.owner = THIS_MODULE,
+	.llseek = no_llseek,
+	.write = pnx4008_wdt_write,
+	.ioctl = pnx4008_wdt_ioctl,
+	.open = pnx4008_wdt_open,
+	.release = pnx4008_wdt_release,
+};
+
+static struct miscdevice pnx4008_wdt_miscdev = {
+	.minor = WATCHDOG_MINOR,
+	.name = "watchdog",
+	.fops = &pnx4008_wdt_fops,
+};
+
+static int pnx4008_wdt_probe(struct platform_device *pdev)
+{
+	int ret = 0, size;
+	struct resource *res;
+
+	if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT)
+		heartbeat = DEFAULT_HEARTBEAT;
+
+	printk(KERN_INFO MODULE_NAME
+		"PNX4008 Watchdog Timer: heartbeat %d sec\n", heartbeat);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res == NULL) {
+		printk(KERN_INFO MODULE_NAME
+			"failed to get memory region resouce\n");
+		return -ENOENT;
+	}
+
+	size = res->end - res->start + 1;
+	wdt_mem = request_mem_region(res->start, size, pdev->name);
+
+	if (wdt_mem == NULL) {
+		printk(KERN_INFO MODULE_NAME "failed to get memory region\n");
+		return -ENOENT;
+	}
+	wdt_base = (void __iomem *)IO_ADDRESS(res->start);
+
+	wdt_clk = clk_get(&pdev->dev, "wdt_ck");
+	if (!wdt_clk) {
+		release_resource(wdt_mem);
+		kfree(wdt_mem);
+		goto out;
+	} else
+		clk_set_rate(wdt_clk, 1);
+
+	ret = misc_register(&pnx4008_wdt_miscdev);
+	if (ret < 0) {
+		printk(KERN_ERR MODULE_NAME "cannot register misc device\n");
+		release_resource(wdt_mem);
+		kfree(wdt_mem);
+		clk_set_rate(wdt_clk, 0);
+	} else {
+		boot_status = (__raw_readl(WDTIM_RES(wdt_base)) & WDOG_RESET) ?
+		    WDIOF_CARDRESET : 0;
+		wdt_disable();		/*disable for now */
+		set_bit(WDT_DEVICE_INITED, &wdt_status);
+	}
+
+out:
+	return ret;
+}
+
+static int pnx4008_wdt_remove(struct platform_device *pdev)
+{
+	if (wdt_mem) {
+		release_resource(wdt_mem);
+		kfree(wdt_mem);
+		wdt_mem = NULL;
+	}
+	if (wdt_clk) {
+		clk_set_rate(wdt_clk, 0);
+		clk_put(wdt_clk);
+		wdt_clk = NULL;
+	}
+	misc_deregister(&pnx4008_wdt_miscdev);
+	return 0;
+}
+
+static struct platform_driver platform_wdt_driver = {
+	.driver = {
+		.name = "watchdog",
+	},
+	.probe = pnx4008_wdt_probe,
+	.remove = pnx4008_wdt_remove,
+};
+
+static int __init pnx4008_wdt_init(void)
+{
+	return platform_driver_register(&platform_wdt_driver);
+}
+
+static void __exit pnx4008_wdt_exit(void)
+{
+	return platform_driver_unregister(&platform_wdt_driver);
+}
+
+module_init(pnx4008_wdt_init);
+module_exit(pnx4008_wdt_exit);
+
+MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>");
+MODULE_DESCRIPTION("PNX4008 Watchdog Driver");
+
+module_param(heartbeat, int, 0);
+MODULE_PARM_DESC(heartbeat,
+		 "Watchdog heartbeat period in seconds from 1 to "
+		 __MODULE_STRING(MAX_HEARTBEAT) ", default "
+		 __MODULE_STRING(DEFAULT_HEARTBEAT));
+
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout,
+		 "Set to 1 to keep watchdog running after device release");
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);