--- /dev/null +++ b/drivers/watchdog/ar2315-wtd.c @@ -0,0 +1,209 @@ +/* + * 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 + * + * Copyright (C) 2008 John Crispin + * Based on EP93xx and ifxmips wdt driver + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_NAME "ar2315-wdt" + +#define CLOCK_RATE 40000000 +#define HEARTBEAT(x) (x < 1 || x > 90 ? 20 : x) + +#define WDT_REG_TIMER 0x00 +#define WDT_REG_CTRL 0x04 + +#define WDT_CTRL_ACT_NONE 0x00000000 /* No action */ +#define WDT_CTRL_ACT_NMI 0x00000001 /* NMI on watchdog */ +#define WDT_CTRL_ACT_RESET 0x00000002 /* reset on watchdog */ + +static int wdt_timeout = 20; +static int started; +static int in_use; +static void __iomem *wdt_base; + +static inline void ar2315_wdt_wr(unsigned reg, u32 val) +{ + iowrite32(val, wdt_base + reg); +} + +static void +ar2315_wdt_enable(void) +{ + ar2315_wdt_wr(WDT_REG_TIMER, wdt_timeout * CLOCK_RATE); +} + +static ssize_t +ar2315_wdt_write(struct file *file, const char __user *data, size_t len, + loff_t *ppos) +{ + if (len) + ar2315_wdt_enable(); + return len; +} + +static int +ar2315_wdt_open(struct inode *inode, struct file *file) +{ + if (in_use) + return -EBUSY; + ar2315_wdt_enable(); + in_use = started = 1; + return nonseekable_open(inode, file); +} + +static int +ar2315_wdt_release(struct inode *inode, struct file *file) +{ + in_use = 0; + return 0; +} + +static irqreturn_t +ar2315_wdt_interrupt(int irq, void *dev) +{ + struct platform_device *pdev = (struct platform_device *)dev; + + if (started) { + dev_crit(&pdev->dev, "watchdog expired, rebooting system\n"); + emergency_restart(); + } else { + ar2315_wdt_wr(WDT_REG_CTRL, 0); + ar2315_wdt_wr(WDT_REG_TIMER, 0); + } + return IRQ_HANDLED; +} + +static struct watchdog_info ident = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, + .identity = "ar2315 Watchdog", +}; + +static long +ar2315_wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + int new_wdt_timeout; + int ret = -ENOIOCTLCMD; + + switch (cmd) { + case WDIOC_GETSUPPORT: + ret = copy_to_user((void __user *)arg, &ident, sizeof(ident)) ? + -EFAULT : 0; + break; + case WDIOC_KEEPALIVE: + ar2315_wdt_enable(); + ret = 0; + break; + case WDIOC_SETTIMEOUT: + ret = get_user(new_wdt_timeout, (int __user *)arg); + if (ret) + break; + wdt_timeout = HEARTBEAT(new_wdt_timeout); + ar2315_wdt_enable(); + break; + case WDIOC_GETTIMEOUT: + ret = put_user(wdt_timeout, (int __user *)arg); + break; + } + return ret; +} + +static const struct file_operations ar2315_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = ar2315_wdt_write, + .unlocked_ioctl = ar2315_wdt_ioctl, + .open = ar2315_wdt_open, + .release = ar2315_wdt_release, +}; + +static struct miscdevice ar2315_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &ar2315_wdt_fops, +}; + +static int +ar2315_wdt_probe(struct platform_device *dev) +{ + struct resource *mem_res, *irq_res; + int ret = 0; + + if (wdt_base) + return -EBUSY; + + irq_res = platform_get_resource(dev, IORESOURCE_IRQ, 0); + if (!irq_res) { + dev_err(&dev->dev, "no IRQ resource\n"); + return -ENOENT; + } + + mem_res = platform_get_resource(dev, IORESOURCE_MEM, 0); + wdt_base = devm_ioremap_resource(&dev->dev, mem_res); + if (IS_ERR(wdt_base)) + return PTR_ERR(wdt_base); + + ret = devm_request_irq(&dev->dev, irq_res->start, ar2315_wdt_interrupt, + IRQF_DISABLED, DRIVER_NAME, dev); + if (ret) { + dev_err(&dev->dev, "failed to register inetrrupt\n"); + goto out; + } + + ret = misc_register(&ar2315_wdt_miscdev); + if (ret) + dev_err(&dev->dev, "failed to register miscdev\n"); + +out: + return ret; +} + +static int +ar2315_wdt_remove(struct platform_device *dev) +{ + misc_deregister(&ar2315_wdt_miscdev); + return 0; +} + +static struct platform_driver ar2315_wdt_driver = { + .probe = ar2315_wdt_probe, + .remove = ar2315_wdt_remove, + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, +}; + +module_platform_driver(ar2315_wdt_driver); + +MODULE_DESCRIPTION("Atheros AR2315 hardware watchdog driver"); +MODULE_AUTHOR("John Crispin "); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRIVER_NAME); --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1113,6 +1113,13 @@ config LANTIQ_WDT help Hardware driver for the Lantiq SoC Watchdog Timer. +config AR2315_WDT + tristate "Atheros AR2315+ WiSoCs Watchdog Timer" + depends on ATHEROS_AR231X + help + Hardware driver for the built-in watchdog timer on the Atheros + AR2315/AR2316 WiSoCs. + # PARISC Architecture # POWERPC Architecture --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -131,6 +131,7 @@ obj-$(CONFIG_GPIO_WDT) += gpio_wdt.o obj-$(CONFIG_PNX833X_WDT) += pnx833x_wdt.o obj-$(CONFIG_SIBYTE_WDOG) += sb_wdog.o obj-$(CONFIG_AR7_WDT) += ar7_wdt.o +obj-$(CONFIG_AR2315_WDT) += ar2315-wtd.o obj-$(CONFIG_TXX9_WDT) += txx9wdt.o obj-$(CONFIG_OCTEON_WDT) += octeon-wdt.o octeon-wdt-y := octeon-wdt-main.o octeon-wdt-nmi.o