diff options
Diffstat (limited to 'drivers/watchdog/nuc900_wdt.c')
-rw-r--r-- | drivers/watchdog/nuc900_wdt.c | 302 |
1 files changed, 0 insertions, 302 deletions
diff --git a/drivers/watchdog/nuc900_wdt.c b/drivers/watchdog/nuc900_wdt.c deleted file mode 100644 index db124cebe838..000000000000 --- a/drivers/watchdog/nuc900_wdt.c +++ /dev/null @@ -1,302 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (c) 2009 Nuvoton technology corporation. - * - * Wan ZongShun <mcuos.com@gmail.com> - */ - -#include <linux/bitops.h> -#include <linux/errno.h> -#include <linux/fs.h> -#include <linux/io.h> -#include <linux/clk.h> -#include <linux/kernel.h> -#include <linux/miscdevice.h> -#include <linux/module.h> -#include <linux/moduleparam.h> -#include <linux/platform_device.h> -#include <linux/slab.h> -#include <linux/interrupt.h> -#include <linux/types.h> -#include <linux/watchdog.h> -#include <linux/uaccess.h> - -#define REG_WTCR 0x1c -#define WTCLK (0x01 << 10) -#define WTE (0x01 << 7) /*wdt enable*/ -#define WTIS (0x03 << 4) -#define WTIF (0x01 << 3) -#define WTRF (0x01 << 2) -#define WTRE (0x01 << 1) -#define WTR (0x01 << 0) -/* - * The watchdog time interval can be calculated via following formula: - * WTIS real time interval (formula) - * 0x00 ((2^ 14 ) * ((external crystal freq) / 256))seconds - * 0x01 ((2^ 16 ) * ((external crystal freq) / 256))seconds - * 0x02 ((2^ 18 ) * ((external crystal freq) / 256))seconds - * 0x03 ((2^ 20 ) * ((external crystal freq) / 256))seconds - * - * The external crystal freq is 15Mhz in the nuc900 evaluation board. - * So 0x00 = +-0.28 seconds, 0x01 = +-1.12 seconds, 0x02 = +-4.48 seconds, - * 0x03 = +- 16.92 seconds.. - */ -#define WDT_HW_TIMEOUT 0x02 -#define WDT_TIMEOUT (HZ/2) -#define WDT_HEARTBEAT 15 - -static int heartbeat = WDT_HEARTBEAT; -module_param(heartbeat, int, 0); -MODULE_PARM_DESC(heartbeat, "Watchdog heartbeats in seconds. " - "(default = " __MODULE_STRING(WDT_HEARTBEAT) ")"); - -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) ")"); - -struct nuc900_wdt { - struct clk *wdt_clock; - struct platform_device *pdev; - void __iomem *wdt_base; - char expect_close; - struct timer_list timer; - spinlock_t wdt_lock; - unsigned long next_heartbeat; -}; - -static unsigned long nuc900wdt_busy; -static struct nuc900_wdt *nuc900_wdt; - -static inline void nuc900_wdt_keepalive(void) -{ - unsigned int val; - - spin_lock(&nuc900_wdt->wdt_lock); - - val = __raw_readl(nuc900_wdt->wdt_base + REG_WTCR); - val |= (WTR | WTIF); - __raw_writel(val, nuc900_wdt->wdt_base + REG_WTCR); - - spin_unlock(&nuc900_wdt->wdt_lock); -} - -static inline void nuc900_wdt_start(void) -{ - unsigned int val; - - spin_lock(&nuc900_wdt->wdt_lock); - - val = __raw_readl(nuc900_wdt->wdt_base + REG_WTCR); - val |= (WTRE | WTE | WTR | WTCLK | WTIF); - val &= ~WTIS; - val |= (WDT_HW_TIMEOUT << 0x04); - __raw_writel(val, nuc900_wdt->wdt_base + REG_WTCR); - - spin_unlock(&nuc900_wdt->wdt_lock); - - nuc900_wdt->next_heartbeat = jiffies + heartbeat * HZ; - mod_timer(&nuc900_wdt->timer, jiffies + WDT_TIMEOUT); -} - -static inline void nuc900_wdt_stop(void) -{ - unsigned int val; - - del_timer(&nuc900_wdt->timer); - - spin_lock(&nuc900_wdt->wdt_lock); - - val = __raw_readl(nuc900_wdt->wdt_base + REG_WTCR); - val &= ~WTE; - __raw_writel(val, nuc900_wdt->wdt_base + REG_WTCR); - - spin_unlock(&nuc900_wdt->wdt_lock); -} - -static inline void nuc900_wdt_ping(void) -{ - nuc900_wdt->next_heartbeat = jiffies + heartbeat * HZ; -} - -static int nuc900_wdt_open(struct inode *inode, struct file *file) -{ - - if (test_and_set_bit(0, &nuc900wdt_busy)) - return -EBUSY; - - nuc900_wdt_start(); - - return stream_open(inode, file); -} - -static int nuc900_wdt_close(struct inode *inode, struct file *file) -{ - if (nuc900_wdt->expect_close == 42) - nuc900_wdt_stop(); - else { - dev_crit(&nuc900_wdt->pdev->dev, - "Unexpected close, not stopping watchdog!\n"); - nuc900_wdt_ping(); - } - - nuc900_wdt->expect_close = 0; - clear_bit(0, &nuc900wdt_busy); - return 0; -} - -static const struct watchdog_info nuc900_wdt_info = { - .identity = "nuc900 watchdog", - .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | - WDIOF_MAGICCLOSE, -}; - -static long nuc900_wdt_ioctl(struct file *file, - unsigned int cmd, unsigned long arg) -{ - void __user *argp = (void __user *)arg; - int __user *p = argp; - int new_value; - - switch (cmd) { - case WDIOC_GETSUPPORT: - return copy_to_user(argp, &nuc900_wdt_info, - sizeof(nuc900_wdt_info)) ? -EFAULT : 0; - case WDIOC_GETSTATUS: - case WDIOC_GETBOOTSTATUS: - return put_user(0, p); - - case WDIOC_KEEPALIVE: - nuc900_wdt_ping(); - return 0; - - case WDIOC_SETTIMEOUT: - if (get_user(new_value, p)) - return -EFAULT; - - heartbeat = new_value; - nuc900_wdt_ping(); - - return put_user(new_value, p); - case WDIOC_GETTIMEOUT: - return put_user(heartbeat, p); - default: - return -ENOTTY; - } -} - -static ssize_t nuc900_wdt_write(struct file *file, const char __user *data, - size_t len, loff_t *ppos) -{ - if (!len) - return 0; - - /* Scan for magic character */ - if (!nowayout) { - size_t i; - - nuc900_wdt->expect_close = 0; - - for (i = 0; i < len; i++) { - char c; - if (get_user(c, data + i)) - return -EFAULT; - if (c == 'V') { - nuc900_wdt->expect_close = 42; - break; - } - } - } - - nuc900_wdt_ping(); - return len; -} - -static void nuc900_wdt_timer_ping(struct timer_list *unused) -{ - if (time_before(jiffies, nuc900_wdt->next_heartbeat)) { - nuc900_wdt_keepalive(); - mod_timer(&nuc900_wdt->timer, jiffies + WDT_TIMEOUT); - } else - dev_warn(&nuc900_wdt->pdev->dev, "Will reset the machine !\n"); -} - -static const struct file_operations nuc900wdt_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .unlocked_ioctl = nuc900_wdt_ioctl, - .open = nuc900_wdt_open, - .release = nuc900_wdt_close, - .write = nuc900_wdt_write, -}; - -static struct miscdevice nuc900wdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &nuc900wdt_fops, -}; - -static int nuc900wdt_probe(struct platform_device *pdev) -{ - int ret = 0; - - nuc900_wdt = devm_kzalloc(&pdev->dev, sizeof(*nuc900_wdt), - GFP_KERNEL); - if (!nuc900_wdt) - return -ENOMEM; - - nuc900_wdt->pdev = pdev; - - spin_lock_init(&nuc900_wdt->wdt_lock); - - nuc900_wdt->wdt_base = devm_platform_ioremap_resource(pdev, 0); - if (IS_ERR(nuc900_wdt->wdt_base)) - return PTR_ERR(nuc900_wdt->wdt_base); - - nuc900_wdt->wdt_clock = devm_clk_get(&pdev->dev, NULL); - if (IS_ERR(nuc900_wdt->wdt_clock)) { - dev_err(&pdev->dev, "failed to find watchdog clock source\n"); - return PTR_ERR(nuc900_wdt->wdt_clock); - } - - clk_enable(nuc900_wdt->wdt_clock); - - timer_setup(&nuc900_wdt->timer, nuc900_wdt_timer_ping, 0); - - ret = misc_register(&nuc900wdt_miscdev); - if (ret) { - dev_err(&pdev->dev, "err register miscdev on minor=%d (%d)\n", - WATCHDOG_MINOR, ret); - goto err_clk; - } - - return 0; - -err_clk: - clk_disable(nuc900_wdt->wdt_clock); - return ret; -} - -static int nuc900wdt_remove(struct platform_device *pdev) -{ - misc_deregister(&nuc900wdt_miscdev); - - clk_disable(nuc900_wdt->wdt_clock); - - return 0; -} - -static struct platform_driver nuc900wdt_driver = { - .probe = nuc900wdt_probe, - .remove = nuc900wdt_remove, - .driver = { - .name = "nuc900-wdt", - }, -}; - -module_platform_driver(nuc900wdt_driver); - -MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>"); -MODULE_DESCRIPTION("Watchdog driver for NUC900"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS("platform:nuc900-wdt"); |