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Diffstat (limited to 'drivers/char/watchdog/s3c2410_wdt.c')
-rw-r--r--drivers/char/watchdog/s3c2410_wdt.c563
1 files changed, 0 insertions, 563 deletions
diff --git a/drivers/char/watchdog/s3c2410_wdt.c b/drivers/char/watchdog/s3c2410_wdt.c
deleted file mode 100644
index 5d1c15f83d23..000000000000
--- a/drivers/char/watchdog/s3c2410_wdt.c
+++ /dev/null
@@ -1,563 +0,0 @@
-/* linux/drivers/char/watchdog/s3c2410_wdt.c
- *
- * Copyright (c) 2004 Simtec Electronics
- * Ben Dooks <ben@simtec.co.uk>
- *
- * S3C2410 Watchdog Timer Support
- *
- * Based on, softdog.c by Alan Cox,
- * (c) Copyright 1996 Alan Cox <alan@redhat.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
- *
- * Changelog:
- * 05-Oct-2004 BJD Added semaphore init to stop crashes on open
- * Fixed tmr_count / wdt_count confusion
- * Added configurable debug
- *
- * 11-Jan-2005 BJD Fixed divide-by-2 in timeout code
- *
- * 25-Jan-2005 DA Added suspend/resume support
- * Replaced reboot notifier with .shutdown method
- *
- * 10-Mar-2005 LCVR Changed S3C2410_VA to S3C24XX_VA
-*/
-
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/types.h>
-#include <linux/timer.h>
-#include <linux/miscdevice.h>
-#include <linux/watchdog.h>
-#include <linux/fs.h>
-#include <linux/init.h>
-#include <linux/platform_device.h>
-#include <linux/interrupt.h>
-#include <linux/clk.h>
-
-#include <asm/uaccess.h>
-#include <asm/io.h>
-
-#include <asm/arch/map.h>
-
-#undef S3C_VA_WATCHDOG
-#define S3C_VA_WATCHDOG (0)
-
-#include <asm/plat-s3c/regs-watchdog.h>
-
-#define PFX "s3c2410-wdt: "
-
-#define CONFIG_S3C2410_WATCHDOG_ATBOOT (0)
-#define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME (15)
-
-static int nowayout = WATCHDOG_NOWAYOUT;
-static int tmr_margin = CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME;
-static int tmr_atboot = CONFIG_S3C2410_WATCHDOG_ATBOOT;
-static int soft_noboot = 0;
-static int debug = 0;
-
-module_param(tmr_margin, int, 0);
-module_param(tmr_atboot, int, 0);
-module_param(nowayout, int, 0);
-module_param(soft_noboot, int, 0);
-module_param(debug, int, 0);
-
-MODULE_PARM_DESC(tmr_margin, "Watchdog tmr_margin in seconds. default=" __MODULE_STRING(CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME) ")");
-
-MODULE_PARM_DESC(tmr_atboot, "Watchdog is started at boot time if set to 1, default=" __MODULE_STRING(CONFIG_S3C2410_WATCHDOG_ATBOOT));
-
-MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
-
-MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, 0 to reboot (default depends on ONLY_TESTING)");
-
-MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug, (default 0)");
-
-
-typedef enum close_state {
- CLOSE_STATE_NOT,
- CLOSE_STATE_ALLOW=0x4021
-} close_state_t;
-
-static DECLARE_MUTEX(open_lock);
-
-static struct device *wdt_dev; /* platform device attached to */
-static struct resource *wdt_mem;
-static struct resource *wdt_irq;
-static struct clk *wdt_clock;
-static void __iomem *wdt_base;
-static unsigned int wdt_count;
-static close_state_t allow_close;
-
-/* watchdog control routines */
-
-#define DBG(msg...) do { \
- if (debug) \
- printk(KERN_INFO msg); \
- } while(0)
-
-/* functions */
-
-static int s3c2410wdt_keepalive(void)
-{
- writel(wdt_count, wdt_base + S3C2410_WTCNT);
- return 0;
-}
-
-static int s3c2410wdt_stop(void)
-{
- unsigned long wtcon;
-
- wtcon = readl(wdt_base + S3C2410_WTCON);
- wtcon &= ~(S3C2410_WTCON_ENABLE | S3C2410_WTCON_RSTEN);
- writel(wtcon, wdt_base + S3C2410_WTCON);
-
- return 0;
-}
-
-static int s3c2410wdt_start(void)
-{
- unsigned long wtcon;
-
- s3c2410wdt_stop();
-
- wtcon = readl(wdt_base + S3C2410_WTCON);
- wtcon |= S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128;
-
- if (soft_noboot) {
- wtcon |= S3C2410_WTCON_INTEN;
- wtcon &= ~S3C2410_WTCON_RSTEN;
- } else {
- wtcon &= ~S3C2410_WTCON_INTEN;
- wtcon |= S3C2410_WTCON_RSTEN;
- }
-
- DBG("%s: wdt_count=0x%08x, wtcon=%08lx\n",
- __FUNCTION__, wdt_count, wtcon);
-
- writel(wdt_count, wdt_base + S3C2410_WTDAT);
- writel(wdt_count, wdt_base + S3C2410_WTCNT);
- writel(wtcon, wdt_base + S3C2410_WTCON);
-
- return 0;
-}
-
-static int s3c2410wdt_set_heartbeat(int timeout)
-{
- unsigned int freq = clk_get_rate(wdt_clock);
- unsigned int count;
- unsigned int divisor = 1;
- unsigned long wtcon;
-
- if (timeout < 1)
- return -EINVAL;
-
- freq /= 128;
- count = timeout * freq;
-
- DBG("%s: count=%d, timeout=%d, freq=%d\n",
- __FUNCTION__, count, timeout, freq);
-
- /* if the count is bigger than the watchdog register,
- then work out what we need to do (and if) we can
- actually make this value
- */
-
- if (count >= 0x10000) {
- for (divisor = 1; divisor <= 0x100; divisor++) {
- if ((count / divisor) < 0x10000)
- break;
- }
-
- if ((count / divisor) >= 0x10000) {
- dev_err(wdt_dev, "timeout %d too big\n", timeout);
- return -EINVAL;
- }
- }
-
- tmr_margin = timeout;
-
- DBG("%s: timeout=%d, divisor=%d, count=%d (%08x)\n",
- __FUNCTION__, timeout, divisor, count, count/divisor);
-
- count /= divisor;
- wdt_count = count;
-
- /* update the pre-scaler */
- wtcon = readl(wdt_base + S3C2410_WTCON);
- wtcon &= ~S3C2410_WTCON_PRESCALE_MASK;
- wtcon |= S3C2410_WTCON_PRESCALE(divisor-1);
-
- writel(count, wdt_base + S3C2410_WTDAT);
- writel(wtcon, wdt_base + S3C2410_WTCON);
-
- return 0;
-}
-
-/*
- * /dev/watchdog handling
- */
-
-static int s3c2410wdt_open(struct inode *inode, struct file *file)
-{
- if(down_trylock(&open_lock))
- return -EBUSY;
-
- if (nowayout)
- __module_get(THIS_MODULE);
-
- allow_close = CLOSE_STATE_NOT;
-
- /* start the timer */
- s3c2410wdt_start();
- return nonseekable_open(inode, file);
-}
-
-static int s3c2410wdt_release(struct inode *inode, struct file *file)
-{
- /*
- * Shut off the timer.
- * Lock it in if it's a module and we set nowayout
- */
-
- if (allow_close == CLOSE_STATE_ALLOW) {
- s3c2410wdt_stop();
- } else {
- dev_err(wdt_dev, "Unexpected close, not stopping watchdog\n");
- s3c2410wdt_keepalive();
- }
-
- allow_close = CLOSE_STATE_NOT;
- up(&open_lock);
- return 0;
-}
-
-static ssize_t s3c2410wdt_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
-{
- /*
- * Refresh the timer.
- */
- if(len) {
- if (!nowayout) {
- size_t i;
-
- /* In case it was set long ago */
- allow_close = CLOSE_STATE_NOT;
-
- for (i = 0; i != len; i++) {
- char c;
-
- if (get_user(c, data + i))
- return -EFAULT;
- if (c == 'V')
- allow_close = CLOSE_STATE_ALLOW;
- }
- }
-
- s3c2410wdt_keepalive();
- }
- return len;
-}
-
-#define OPTIONS WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE
-
-static struct watchdog_info s3c2410_wdt_ident = {
- .options = OPTIONS,
- .firmware_version = 0,
- .identity = "S3C2410 Watchdog",
-};
-
-
-static int s3c2410wdt_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- void __user *argp = (void __user *)arg;
- int __user *p = argp;
- int new_margin;
-
- switch (cmd) {
- default:
- return -ENOTTY;
-
- case WDIOC_GETSUPPORT:
- return copy_to_user(argp, &s3c2410_wdt_ident,
- sizeof(s3c2410_wdt_ident)) ? -EFAULT : 0;
-
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- return put_user(0, p);
-
- case WDIOC_KEEPALIVE:
- s3c2410wdt_keepalive();
- return 0;
-
- case WDIOC_SETTIMEOUT:
- if (get_user(new_margin, p))
- return -EFAULT;
-
- if (s3c2410wdt_set_heartbeat(new_margin))
- return -EINVAL;
-
- s3c2410wdt_keepalive();
- return put_user(tmr_margin, p);
-
- case WDIOC_GETTIMEOUT:
- return put_user(tmr_margin, p);
- }
-}
-
-/* kernel interface */
-
-static const struct file_operations s3c2410wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = s3c2410wdt_write,
- .ioctl = s3c2410wdt_ioctl,
- .open = s3c2410wdt_open,
- .release = s3c2410wdt_release,
-};
-
-static struct miscdevice s3c2410wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &s3c2410wdt_fops,
-};
-
-/* interrupt handler code */
-
-static irqreturn_t s3c2410wdt_irq(int irqno, void *param)
-{
- dev_info(wdt_dev, "watchdog timer expired (irq)\n");
-
- s3c2410wdt_keepalive();
- return IRQ_HANDLED;
-}
-/* device interface */
-
-static int s3c2410wdt_probe(struct platform_device *pdev)
-{
- struct resource *res;
- struct device *dev;
- unsigned int wtcon;
- int started = 0;
- int ret;
- int size;
-
- DBG("%s: probe=%p\n", __FUNCTION__, pdev);
-
- dev = &pdev->dev;
- wdt_dev = &pdev->dev;
-
- /* get the memory region for the watchdog timer */
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (res == NULL) {
- dev_err(dev, "no memory resource specified\n");
- return -ENOENT;
- }
-
- size = (res->end-res->start)+1;
- wdt_mem = request_mem_region(res->start, size, pdev->name);
- if (wdt_mem == NULL) {
- dev_err(dev, "failed to get memory region\n");
- ret = -ENOENT;
- goto err_req;
- }
-
- wdt_base = ioremap(res->start, size);
- if (wdt_base == 0) {
- dev_err(dev, "failed to ioremap() region\n");
- ret = -EINVAL;
- goto err_req;
- }
-
- DBG("probe: mapped wdt_base=%p\n", wdt_base);
-
- wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
- if (wdt_irq == NULL) {
- dev_err(dev, "no irq resource specified\n");
- ret = -ENOENT;
- goto err_map;
- }
-
- ret = request_irq(wdt_irq->start, s3c2410wdt_irq, 0, pdev->name, pdev);
- if (ret != 0) {
- dev_err(dev, "failed to install irq (%d)\n", ret);
- goto err_map;
- }
-
- wdt_clock = clk_get(&pdev->dev, "watchdog");
- if (IS_ERR(wdt_clock)) {
- dev_err(dev, "failed to find watchdog clock source\n");
- ret = PTR_ERR(wdt_clock);
- goto err_irq;
- }
-
- clk_enable(wdt_clock);
-
- /* see if we can actually set the requested timer margin, and if
- * not, try the default value */
-
- if (s3c2410wdt_set_heartbeat(tmr_margin)) {
- started = s3c2410wdt_set_heartbeat(CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME);
-
- if (started == 0) {
- dev_info(dev,"tmr_margin value out of range, default %d used\n",
- CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME);
- } else {
- dev_info(dev, "default timer value is out of range, cannot start\n");
- }
- }
-
- ret = misc_register(&s3c2410wdt_miscdev);
- if (ret) {
- dev_err(dev, "cannot register miscdev on minor=%d (%d)\n",
- WATCHDOG_MINOR, ret);
- goto err_clk;
- }
-
- if (tmr_atboot && started == 0) {
- dev_info(dev, "starting watchdog timer\n");
- s3c2410wdt_start();
- } else if (!tmr_atboot) {
- /* if we're not enabling the watchdog, then ensure it is
- * disabled if it has been left running from the bootloader
- * or other source */
-
- s3c2410wdt_stop();
- }
-
- /* print out a statement of readiness */
-
- wtcon = readl(wdt_base + S3C2410_WTCON);
-
- dev_info(dev, "watchdog %sactive, reset %sabled, irq %sabled\n",
- (wtcon & S3C2410_WTCON_ENABLE) ? "" : "in",
- (wtcon & S3C2410_WTCON_RSTEN) ? "" : "dis",
- (wtcon & S3C2410_WTCON_INTEN) ? "" : "en");
-
- return 0;
-
- err_clk:
- clk_disable(wdt_clock);
- clk_put(wdt_clock);
-
- err_irq:
- free_irq(wdt_irq->start, pdev);
-
- err_map:
- iounmap(wdt_base);
-
- err_req:
- release_resource(wdt_mem);
- kfree(wdt_mem);
-
- return ret;
-}
-
-static int s3c2410wdt_remove(struct platform_device *dev)
-{
- release_resource(wdt_mem);
- kfree(wdt_mem);
- wdt_mem = NULL;
-
- free_irq(wdt_irq->start, dev);
- wdt_irq = NULL;
-
- clk_disable(wdt_clock);
- clk_put(wdt_clock);
- wdt_clock = NULL;
-
- iounmap(wdt_base);
- misc_deregister(&s3c2410wdt_miscdev);
- return 0;
-}
-
-static void s3c2410wdt_shutdown(struct platform_device *dev)
-{
- s3c2410wdt_stop();
-}
-
-#ifdef CONFIG_PM
-
-static unsigned long wtcon_save;
-static unsigned long wtdat_save;
-
-static int s3c2410wdt_suspend(struct platform_device *dev, pm_message_t state)
-{
- /* Save watchdog state, and turn it off. */
- wtcon_save = readl(wdt_base + S3C2410_WTCON);
- wtdat_save = readl(wdt_base + S3C2410_WTDAT);
-
- /* Note that WTCNT doesn't need to be saved. */
- s3c2410wdt_stop();
-
- return 0;
-}
-
-static int s3c2410wdt_resume(struct platform_device *dev)
-{
- /* Restore watchdog state. */
-
- writel(wtdat_save, wdt_base + S3C2410_WTDAT);
- writel(wtdat_save, wdt_base + S3C2410_WTCNT); /* Reset count */
- writel(wtcon_save, wdt_base + S3C2410_WTCON);
-
- printk(KERN_INFO PFX "watchdog %sabled\n",
- (wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis");
-
- return 0;
-}
-
-#else
-#define s3c2410wdt_suspend NULL
-#define s3c2410wdt_resume NULL
-#endif /* CONFIG_PM */
-
-
-static struct platform_driver s3c2410wdt_driver = {
- .probe = s3c2410wdt_probe,
- .remove = s3c2410wdt_remove,
- .shutdown = s3c2410wdt_shutdown,
- .suspend = s3c2410wdt_suspend,
- .resume = s3c2410wdt_resume,
- .driver = {
- .owner = THIS_MODULE,
- .name = "s3c2410-wdt",
- },
-};
-
-
-static char banner[] __initdata = KERN_INFO "S3C2410 Watchdog Timer, (c) 2004 Simtec Electronics\n";
-
-static int __init watchdog_init(void)
-{
- printk(banner);
- return platform_driver_register(&s3c2410wdt_driver);
-}
-
-static void __exit watchdog_exit(void)
-{
- platform_driver_unregister(&s3c2410wdt_driver);
-}
-
-module_init(watchdog_init);
-module_exit(watchdog_exit);
-
-MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>, "
- "Dimitry Andric <dimitry.andric@tomtom.com>");
-MODULE_DESCRIPTION("S3C2410 Watchdog Device Driver");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);