--- /dev/null
+/*
+ * 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);
projects / linux-2.6 / commitdiff