diff options
Diffstat (limited to 'drivers/watchdog')
| -rw-r--r-- | drivers/watchdog/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/watchdog/Makefile | 1 | ||||
| -rw-r--r-- | drivers/watchdog/twl4030_wdt.c | 272 |
3 files changed, 280 insertions, 0 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 631599b7e6a..c4c2206d6f3 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -250,6 +250,13 @@ config COH901327_WATCHDOG This watchdog is used to reset the system and thus cannot be compiled as a module. +config TWL4030_WATCHDOG + tristate "TWL4030 Watchdog" + depends on TWL4030_CORE + help + Support for TI TWL4030 watchdog. Say 'Y' here to enable the + watchdog timer support for TWL4030 chips. + # AVR32 Architecture config AT32AP700X_WDT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index c3a22d3d549..2c54c04858b 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -28,6 +28,7 @@ obj-$(CONFIG_USBPCWATCHDOG) += pcwd_usb.o obj-$(CONFIG_AT91RM9200_WATCHDOG) += at91rm9200_wdt.o obj-$(CONFIG_AT91SAM9X_WATCHDOG) += at91sam9_wdt.o obj-$(CONFIG_OMAP_WATCHDOG) += omap_wdt.o +obj-$(CONFIG_TWL4030_WATCHDOG) += twl4030_wdt.o obj-$(CONFIG_21285_WATCHDOG) += wdt285.o obj-$(CONFIG_977_WATCHDOG) += wdt977.o obj-$(CONFIG_IXP2000_WATCHDOG) += ixp2000_wdt.o diff --git a/drivers/watchdog/twl4030_wdt.c b/drivers/watchdog/twl4030_wdt.c new file mode 100644 index 00000000000..cb46556f297 --- /dev/null +++ b/drivers/watchdog/twl4030_wdt.c @@ -0,0 +1,272 @@ +/* + * Copyright (C) Nokia Corporation + * + * Written by Timo Kokkonen <timo.t.kokkonen at nokia.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 + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/watchdog.h> +#include <linux/platform_device.h> +#include <linux/miscdevice.h> +#include <linux/uaccess.h> +#include <linux/i2c/twl4030.h> + +#define TWL4030_WATCHDOG_CFG_REG_OFFS 0x3 + +#define TWL4030_WDT_STATE_OPEN 0x1 +#define TWL4030_WDT_STATE_ACTIVE 0x8 + +static struct platform_device *twl4030_wdt_dev; + +struct twl4030_wdt { + struct miscdevice miscdev; + int timer_margin; + unsigned long state; +}; + +static int nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, int, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " + "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +static int twl4030_wdt_write(unsigned char val) +{ + return twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, val, + TWL4030_WATCHDOG_CFG_REG_OFFS); +} + +static int twl4030_wdt_enable(struct twl4030_wdt *wdt) +{ + return twl4030_wdt_write(wdt->timer_margin + 1); +} + +static int twl4030_wdt_disable(struct twl4030_wdt *wdt) +{ + return twl4030_wdt_write(0); +} + +static int twl4030_wdt_set_timeout(struct twl4030_wdt *wdt, int timeout) +{ + if (timeout < 0 || timeout > 30) { + dev_warn(wdt->miscdev.parent, + "Timeout can only be in the range [0-30] seconds"); + return -EINVAL; + } + wdt->timer_margin = timeout; + return twl4030_wdt_enable(wdt); +} + +static ssize_t twl4030_wdt_write_fop(struct file *file, + const char __user *data, size_t len, loff_t *ppos) +{ + struct twl4030_wdt *wdt = file->private_data; + + if (len) + twl4030_wdt_enable(wdt); + + return len; +} + +static long twl4030_wdt_ioctl(struct file *file, + unsigned int cmd, unsigned long arg) +{ + void __user *argp = (void __user *)arg; + int __user *p = argp; + int new_margin; + struct twl4030_wdt *wdt = file->private_data; + + static const struct watchdog_info twl4030_wd_ident = { + .identity = "TWL4030 Watchdog", + .options = WDIOF_SETTIMEOUT, + .firmware_version = 0, + }; + + switch (cmd) { + case WDIOC_GETSUPPORT: + return copy_to_user(argp, &twl4030_wd_ident, + sizeof(twl4030_wd_ident)) ? -EFAULT : 0; + + case WDIOC_GETSTATUS: + case WDIOC_GETBOOTSTATUS: + return put_user(0, p); + + case WDIOC_KEEPALIVE: + twl4030_wdt_enable(wdt); + break; + + case WDIOC_SETTIMEOUT: + if (get_user(new_margin, p)) + return -EFAULT; + if (twl4030_wdt_set_timeout(wdt, new_margin)) + return -EINVAL; + return put_user(wdt->timer_margin, p); + + case WDIOC_GETTIMEOUT: + return put_user(wdt->timer_margin, p); + + default: + return -ENOTTY; + } + + return 0; +} + +static int twl4030_wdt_open(struct inode *inode, struct file *file) +{ + struct twl4030_wdt *wdt = platform_get_drvdata(twl4030_wdt_dev); + + /* /dev/watchdog can only be opened once */ + if (test_and_set_bit(0, &wdt->state)) + return -EBUSY; + + wdt->state |= TWL4030_WDT_STATE_ACTIVE; + file->private_data = (void *) wdt; + + twl4030_wdt_enable(wdt); + return nonseekable_open(inode, file); +} + +static int twl4030_wdt_release(struct inode *inode, struct file *file) +{ + struct twl4030_wdt *wdt = file->private_data; + if (nowayout) { + dev_alert(wdt->miscdev.parent, + "Unexpected close, watchdog still running!\n"); + twl4030_wdt_enable(wdt); + } else { + if (twl4030_wdt_disable(wdt)) + return -EFAULT; + wdt->state &= ~TWL4030_WDT_STATE_ACTIVE; + } + + clear_bit(0, &wdt->state); + return 0; +} + +static const struct file_operations twl4030_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .open = twl4030_wdt_open, + .release = twl4030_wdt_release, + .unlocked_ioctl = twl4030_wdt_ioctl, + .write = twl4030_wdt_write_fop, +}; + +static int __devinit twl4030_wdt_probe(struct platform_device *pdev) +{ + int ret = 0; + struct twl4030_wdt *wdt; + + wdt = kzalloc(sizeof(struct twl4030_wdt), GFP_KERNEL); + if (!wdt) + return -ENOMEM; + + wdt->state = 0; + wdt->timer_margin = 30; + wdt->miscdev.parent = &pdev->dev; + wdt->miscdev.fops = &twl4030_wdt_fops; + wdt->miscdev.minor = WATCHDOG_MINOR; + wdt->miscdev.name = "watchdog"; + + platform_set_drvdata(pdev, wdt); + + twl4030_wdt_dev = pdev; + + ret = misc_register(&wdt->miscdev); + if (ret) { + dev_err(wdt->miscdev.parent, + "Failed to register misc device\n"); + platform_set_drvdata(pdev, NULL); + kfree(wdt); + twl4030_wdt_dev = NULL; + return ret; + } + return 0; +} + +static int __devexit twl4030_wdt_remove(struct platform_device *pdev) +{ + struct twl4030_wdt *wdt = platform_get_drvdata(pdev); + + if (wdt->state & TWL4030_WDT_STATE_ACTIVE) + if (twl4030_wdt_disable(wdt)) + return -EFAULT; + + wdt->state &= ~TWL4030_WDT_STATE_ACTIVE; + misc_deregister(&wdt->miscdev); + + platform_set_drvdata(pdev, NULL); + kfree(wdt); + twl4030_wdt_dev = NULL; + + return 0; +} + +#ifdef CONFIG_PM +static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct twl4030_wdt *wdt = platform_get_drvdata(pdev); + if (wdt->state & TWL4030_WDT_STATE_ACTIVE) + return twl4030_wdt_disable(wdt); + + return 0; +} + +static int twl4030_wdt_resume(struct platform_device *pdev) +{ + struct twl4030_wdt *wdt = platform_get_drvdata(pdev); + if (wdt->state & TWL4030_WDT_STATE_ACTIVE) + return twl4030_wdt_enable(wdt); + + return 0; +} +#else +#define twl4030_wdt_suspend NULL +#define twl4030_wdt_resume NULL +#endif + +static struct platform_driver twl4030_wdt_driver = { + .probe = twl4030_wdt_probe, + .remove = __devexit_p(twl4030_wdt_remove), + .suspend = twl4030_wdt_suspend, + .resume = twl4030_wdt_resume, + .driver = { + .owner = THIS_MODULE, + .name = "twl4030_wdt", + }, +}; + +static int __devinit twl4030_wdt_init(void) +{ + return platform_driver_register(&twl4030_wdt_driver); +} +module_init(twl4030_wdt_init); + +static void __devexit twl4030_wdt_exit(void) +{ + platform_driver_unregister(&twl4030_wdt_driver); +} +module_exit(twl4030_wdt_exit); + +MODULE_AUTHOR("Nokia Corporation"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); +MODULE_ALIAS("platform:twl4030_wdt"); + |