diff options
Diffstat (limited to 'drivers/watchdog/of_xilinx_wdt.c')
| -rw-r--r-- | drivers/watchdog/of_xilinx_wdt.c | 204 |
1 files changed, 32 insertions, 172 deletions
diff --git a/drivers/watchdog/of_xilinx_wdt.c b/drivers/watchdog/of_xilinx_wdt.c index 19fa92d01f5d..0e6c188f55ae 100644 --- a/drivers/watchdog/of_xilinx_wdt.c +++ b/drivers/watchdog/of_xilinx_wdt.c @@ -1,6 +1,7 @@ /* * Watchdog Device Driver for Xilinx axi/xps_timebase_wdt * + * (C) Copyright 2013 - 2014 Xilinx, Inc. * (C) Copyright 2011 (Alejandro Cabrera <aldaya@gmail.com>) * * This program is free software; you can redistribute it and/or @@ -14,12 +15,9 @@ #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> -#include <linux/fs.h> -#include <linux/miscdevice.h> #include <linux/ioport.h> #include <linux/watchdog.h> #include <linux/io.h> -#include <linux/uaccess.h> #include <linux/of.h> #include <linux/of_device.h> #include <linux/of_address.h> @@ -47,22 +45,18 @@ struct xwdt_device { struct resource res; void __iomem *base; - u32 nowayout; u32 wdt_interval; - u32 boot_status; }; static struct xwdt_device xdev; static u32 timeout; static u32 control_status_reg; -static u8 expect_close; static u8 no_timeout; -static unsigned long driver_open; static DEFINE_SPINLOCK(spinlock); -static void xwdt_start(void) +static int xilinx_wdt_start(struct watchdog_device *wdd) { spin_lock(&spinlock); @@ -76,9 +70,11 @@ static void xwdt_start(void) iowrite32(XWT_CSRX_EWDT2_MASK, xdev.base + XWT_TWCSR1_OFFSET); spin_unlock(&spinlock); + + return 0; } -static void xwdt_stop(void) +static int xilinx_wdt_stop(struct watchdog_device *wdd) { spin_lock(&spinlock); @@ -91,9 +87,11 @@ static void xwdt_stop(void) spin_unlock(&spinlock); pr_info("Stopped!\n"); + + return 0; } -static void xwdt_keepalive(void) +static int xilinx_wdt_keepalive(struct watchdog_device *wdd) { spin_lock(&spinlock); @@ -102,23 +100,28 @@ static void xwdt_keepalive(void) iowrite32(control_status_reg, xdev.base + XWT_TWCSR0_OFFSET); spin_unlock(&spinlock); -} -static void xwdt_get_status(int *status) -{ - int new_status; + return 0; +} - spin_lock(&spinlock); +static const struct watchdog_info xilinx_wdt_ident = { + .options = WDIOF_MAGICCLOSE | + WDIOF_KEEPALIVEPING, + .firmware_version = 1, + .identity = WATCHDOG_NAME, +}; - control_status_reg = ioread32(xdev.base + XWT_TWCSR0_OFFSET); - new_status = ((control_status_reg & - (XWT_CSR0_WRS_MASK | XWT_CSR0_WDS_MASK)) != 0); - spin_unlock(&spinlock); +static const struct watchdog_ops xilinx_wdt_ops = { + .owner = THIS_MODULE, + .start = xilinx_wdt_start, + .stop = xilinx_wdt_stop, + .ping = xilinx_wdt_keepalive, +}; - *status = 0; - if (new_status & 1) - *status |= WDIOF_CARDRESET; -} +static struct watchdog_device xilinx_wdt_wdd = { + .info = &xilinx_wdt_ident, + .ops = &xilinx_wdt_ops, +}; static u32 xwdt_selftest(void) { @@ -145,139 +148,6 @@ static u32 xwdt_selftest(void) return XWT_TIMER_FAILED; } -static int xwdt_open(struct inode *inode, struct file *file) -{ - /* Only one process can handle the wdt at a time */ - if (test_and_set_bit(0, &driver_open)) - return -EBUSY; - - /* Make sure that the module are always loaded...*/ - if (xdev.nowayout) - __module_get(THIS_MODULE); - - xwdt_start(); - pr_info("Started...\n"); - - return nonseekable_open(inode, file); -} - -static int xwdt_release(struct inode *inode, struct file *file) -{ - if (expect_close == 42) { - xwdt_stop(); - } else { - pr_crit("Unexpected close, not stopping watchdog!\n"); - xwdt_keepalive(); - } - - clear_bit(0, &driver_open); - expect_close = 0; - return 0; -} - -/* - * xwdt_write: - * @file: file handle to the watchdog - * @buf: buffer to write (unused as data does not matter here - * @count: count of bytes - * @ppos: pointer to the position to write. No seeks allowed - * - * A write to a watchdog device is defined as a keepalive signal. Any - * write of data will do, as we don't define content meaning. - */ -static ssize_t xwdt_write(struct file *file, const char __user *buf, - size_t len, loff_t *ppos) -{ - if (len) { - if (!xdev.nowayout) { - size_t i; - - /* In case it was set long ago */ - expect_close = 0; - - for (i = 0; i != len; i++) { - char c; - - if (get_user(c, buf + i)) - return -EFAULT; - if (c == 'V') - expect_close = 42; - } - } - xwdt_keepalive(); - } - return len; -} - -static const struct watchdog_info ident = { - .options = WDIOF_MAGICCLOSE | - WDIOF_KEEPALIVEPING, - .firmware_version = 1, - .identity = WATCHDOG_NAME, -}; - -/* - * xwdt_ioctl: - * @file: file handle to the device - * @cmd: watchdog command - * @arg: argument pointer - * - * The watchdog API defines a common set of functions for all watchdogs - * according to their available features. - */ -static long xwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) -{ - int status; - - union { - struct watchdog_info __user *ident; - int __user *i; - } uarg; - - uarg.i = (int __user *)arg; - - switch (cmd) { - case WDIOC_GETSUPPORT: - return copy_to_user(uarg.ident, &ident, - sizeof(ident)) ? -EFAULT : 0; - - case WDIOC_GETBOOTSTATUS: - return put_user(xdev.boot_status, uarg.i); - - case WDIOC_GETSTATUS: - xwdt_get_status(&status); - return put_user(status, uarg.i); - - case WDIOC_KEEPALIVE: - xwdt_keepalive(); - return 0; - - case WDIOC_GETTIMEOUT: - if (no_timeout) - return -ENOTTY; - else - return put_user(timeout, uarg.i); - - default: - return -ENOTTY; - } -} - -static const struct file_operations xwdt_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .write = xwdt_write, - .open = xwdt_open, - .release = xwdt_release, - .unlocked_ioctl = xwdt_ioctl, -}; - -static struct miscdevice xwdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &xwdt_fops, -}; - static int xwdt_probe(struct platform_device *pdev) { int rc; @@ -313,7 +183,7 @@ static int xwdt_probe(struct platform_device *pdev) "xlnx,wdt-enable-once", NULL); if (tmptr == NULL) { pr_warn("Parameter \"xlnx,wdt-enable-once\" not found in device tree!\n"); - xdev.nowayout = WATCHDOG_NOWAYOUT; + watchdog_set_nowayout(&xilinx_wdt_wdd, true); } /* @@ -343,24 +213,14 @@ static int xwdt_probe(struct platform_device *pdev) goto unmap_io; } - xwdt_get_status(&xdev.boot_status); - - rc = misc_register(&xwdt_miscdev); + rc = watchdog_register_device(&xilinx_wdt_wdd); if (rc) { - pr_err("cannot register miscdev on minor=%d (err=%d)\n", - xwdt_miscdev.minor, rc); + pr_err("cannot register watchdog (err=%d)\n", rc); goto unmap_io; } - if (no_timeout) - pr_info("driver loaded (timeout=? sec, nowayout=%d)\n", - xdev.nowayout); - else - pr_info("driver loaded (timeout=%d sec, nowayout=%d)\n", - timeout, xdev.nowayout); - - expect_close = 0; - clear_bit(0, &driver_open); + dev_info(&pdev->dev, "Xilinx Watchdog Timer at %p with timeout %ds\n", + xdev.base, timeout); return 0; @@ -374,7 +234,7 @@ err_out: static int xwdt_remove(struct platform_device *dev) { - misc_deregister(&xwdt_miscdev); + watchdog_unregister_device(&xilinx_wdt_wdd); iounmap(xdev.base); release_mem_region(xdev.res.start, resource_size(&xdev.res)); |