+++ /dev/null
-/*
- * Copyright (C) 2008-2009 Avionic Design GmbH
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <linux/fs.h>
-#include <linux/gfp.h>
-#include <linux/io.h>
-#include <linux/miscdevice.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/types.h>
-#include <linux/uaccess.h>
-#include <linux/watchdog.h>
-
-#define WATCHDOG_NAME "adx-wdt"
-
-/* register offsets */
-#define ADX_WDT_CONTROL 0x00
-#define ADX_WDT_CONTROL_ENABLE (1 << 0)
-#define ADX_WDT_CONTROL_nRESET (1 << 1)
-#define ADX_WDT_TIMEOUT 0x08
-
-static struct platform_device *adx_wdt_dev;
-static unsigned long driver_open;
-
-#define WDT_STATE_STOP 0
-#define WDT_STATE_START 1
-
-struct adx_wdt {
- void __iomem *base;
- unsigned long timeout;
- unsigned int state;
- unsigned int wake;
- spinlock_t lock;
-};
-
-static const struct watchdog_info adx_wdt_info = {
- .identity = "Avionic Design Xanthos Watchdog",
- .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
-};
-
-static void adx_wdt_start_locked(struct adx_wdt *wdt)
-{
- u32 ctrl;
-
- ctrl = readl(wdt->base + ADX_WDT_CONTROL);
- ctrl |= ADX_WDT_CONTROL_ENABLE;
- writel(ctrl, wdt->base + ADX_WDT_CONTROL);
- wdt->state = WDT_STATE_START;
-}
-
-static void adx_wdt_start(struct adx_wdt *wdt)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&wdt->lock, flags);
- adx_wdt_start_locked(wdt);
- spin_unlock_irqrestore(&wdt->lock, flags);
-}
-
-static void adx_wdt_stop_locked(struct adx_wdt *wdt)
-{
- u32 ctrl;
-
- ctrl = readl(wdt->base + ADX_WDT_CONTROL);
- ctrl &= ~ADX_WDT_CONTROL_ENABLE;
- writel(ctrl, wdt->base + ADX_WDT_CONTROL);
- wdt->state = WDT_STATE_STOP;
-}
-
-static void adx_wdt_stop(struct adx_wdt *wdt)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&wdt->lock, flags);
- adx_wdt_stop_locked(wdt);
- spin_unlock_irqrestore(&wdt->lock, flags);
-}
-
-static void adx_wdt_set_timeout(struct adx_wdt *wdt, unsigned long seconds)
-{
- unsigned long timeout = seconds * 1000;
- unsigned long flags;
- unsigned int state;
-
- spin_lock_irqsave(&wdt->lock, flags);
- state = wdt->state;
- adx_wdt_stop_locked(wdt);
- writel(timeout, wdt->base + ADX_WDT_TIMEOUT);
-
- if (state == WDT_STATE_START)
- adx_wdt_start_locked(wdt);
-
- wdt->timeout = timeout;
- spin_unlock_irqrestore(&wdt->lock, flags);
-}
-
-static void adx_wdt_get_timeout(struct adx_wdt *wdt, unsigned long *seconds)
-{
- *seconds = wdt->timeout / 1000;
-}
-
-static void adx_wdt_keepalive(struct adx_wdt *wdt)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&wdt->lock, flags);
- writel(wdt->timeout, wdt->base + ADX_WDT_TIMEOUT);
- spin_unlock_irqrestore(&wdt->lock, flags);
-}
-
-static int adx_wdt_open(struct inode *inode, struct file *file)
-{
- struct adx_wdt *wdt = platform_get_drvdata(adx_wdt_dev);
-
- if (test_and_set_bit(0, &driver_open))
- return -EBUSY;
-
- file->private_data = wdt;
- adx_wdt_set_timeout(wdt, 30);
- adx_wdt_start(wdt);
-
- return nonseekable_open(inode, file);
-}
-
-static int adx_wdt_release(struct inode *inode, struct file *file)
-{
- struct adx_wdt *wdt = file->private_data;
-
- adx_wdt_stop(wdt);
- clear_bit(0, &driver_open);
-
- return 0;
-}
-
-static long adx_wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
- struct adx_wdt *wdt = file->private_data;
- void __user *argp = (void __user *)arg;
- unsigned long __user *p = argp;
- unsigned long seconds = 0;
- unsigned int options;
- long ret = -EINVAL;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- if (copy_to_user(argp, &adx_wdt_info, sizeof(adx_wdt_info)))
- return -EFAULT;
- else
- return 0;
-
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- return put_user(0, p);
-
- case WDIOC_KEEPALIVE:
- adx_wdt_keepalive(wdt);
- return 0;
-
- case WDIOC_SETTIMEOUT:
- if (get_user(seconds, p))
- return -EFAULT;
-
- adx_wdt_set_timeout(wdt, seconds);
-
- /* fallthrough */
- case WDIOC_GETTIMEOUT:
- adx_wdt_get_timeout(wdt, &seconds);
- return put_user(seconds, p);
-
- case WDIOC_SETOPTIONS:
- if (copy_from_user(&options, argp, sizeof(options)))
- return -EFAULT;
-
- if (options & WDIOS_DISABLECARD) {
- adx_wdt_stop(wdt);
- ret = 0;
- }
-
- if (options & WDIOS_ENABLECARD) {
- adx_wdt_start(wdt);
- ret = 0;
- }
-
- return ret;
-
- default:
- break;
- }
-
- return -ENOTTY;
-}
-
-static ssize_t adx_wdt_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
-{
- struct adx_wdt *wdt = file->private_data;
-
- if (len)
- adx_wdt_keepalive(wdt);
-
- return len;
-}
-
-static const struct file_operations adx_wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .open = adx_wdt_open,
- .release = adx_wdt_release,
- .unlocked_ioctl = adx_wdt_ioctl,
- .write = adx_wdt_write,
-};
-
-static struct miscdevice adx_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &adx_wdt_fops,
-};
-
-static int __devinit adx_wdt_probe(struct platform_device *pdev)
-{
- struct resource *res;
- struct adx_wdt *wdt;
- int ret = 0;
- u32 ctrl;
-
- wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
- if (!wdt) {
- dev_err(&pdev->dev, "cannot allocate WDT structure\n");
- return -ENOMEM;
- }
-
- spin_lock_init(&wdt->lock);
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res) {
- dev_err(&pdev->dev, "cannot obtain I/O memory region\n");
- return -ENXIO;
- }
-
- res = devm_request_mem_region(&pdev->dev, res->start,
- resource_size(res), res->name);
- if (!res) {
- dev_err(&pdev->dev, "cannot request I/O memory region\n");
- return -ENXIO;
- }
-
- wdt->base = devm_ioremap_nocache(&pdev->dev, res->start,
- resource_size(res));
- if (!wdt->base) {
- dev_err(&pdev->dev, "cannot remap I/O memory region\n");
- return -ENXIO;
- }
-
- /* disable watchdog and reboot on timeout */
- ctrl = readl(wdt->base + ADX_WDT_CONTROL);
- ctrl &= ~ADX_WDT_CONTROL_ENABLE;
- ctrl &= ~ADX_WDT_CONTROL_nRESET;
- writel(ctrl, wdt->base + ADX_WDT_CONTROL);
-
- platform_set_drvdata(pdev, wdt);
- adx_wdt_dev = pdev;
-
- ret = misc_register(&adx_wdt_miscdev);
- if (ret) {
- dev_err(&pdev->dev, "cannot register miscdev on minor %d "
- "(err=%d)\n", WATCHDOG_MINOR, ret);
- return ret;
- }
-
- return 0;
-}
-
-static int __devexit adx_wdt_remove(struct platform_device *pdev)
-{
- struct adx_wdt *wdt = platform_get_drvdata(pdev);
-
- misc_deregister(&adx_wdt_miscdev);
- adx_wdt_stop(wdt);
- platform_set_drvdata(pdev, NULL);
-
- return 0;
-}
-
-static void adx_wdt_shutdown(struct platform_device *pdev)
-{
- struct adx_wdt *wdt = platform_get_drvdata(pdev);
- adx_wdt_stop(wdt);
-}
-
-#ifdef CONFIG_PM
-static int adx_wdt_suspend(struct device *dev)
-{
- struct platform_device *pdev = to_platform_device(dev);
- struct adx_wdt *wdt = platform_get_drvdata(pdev);
-
- wdt->wake = (wdt->state == WDT_STATE_START) ? 1 : 0;
- adx_wdt_stop(wdt);
-
- return 0;
-}
-
-static int adx_wdt_resume(struct device *dev)
-{
- struct platform_device *pdev = to_platform_device(dev);
- struct adx_wdt *wdt = platform_get_drvdata(pdev);
-
- if (wdt->wake)
- adx_wdt_start(wdt);
-
- return 0;
-}
-
-static const struct dev_pm_ops adx_wdt_pm_ops = {
- .suspend = adx_wdt_suspend,
- .resume = adx_wdt_resume,
-};
-
-# define ADX_WDT_PM_OPS (&adx_wdt_pm_ops)
-#else
-# define ADX_WDT_PM_OPS NULL
-#endif
-
-static struct platform_driver adx_wdt_driver = {
- .probe = adx_wdt_probe,
- .remove = __devexit_p(adx_wdt_remove),
- .shutdown = adx_wdt_shutdown,
- .driver = {
- .name = WATCHDOG_NAME,
- .owner = THIS_MODULE,
- .pm = ADX_WDT_PM_OPS,
- },
-};
-
-static int __init adx_wdt_init(void)
-{
- return platform_driver_register(&adx_wdt_driver);
-}
-
-static void __exit adx_wdt_exit(void)
-{
- platform_driver_unregister(&adx_wdt_driver);
-}
-
-module_init(adx_wdt_init);
-module_exit(adx_wdt_exit);
-
-MODULE_DESCRIPTION("Avionic Design Xanthos Watchdog Driver");
-MODULE_LICENSE("GPL v2");
-MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
git.openpandora.org / pandora-kernel.git / commitdiff