From b1fa888e0124763e5bafda074874fc7ac0f2f23f Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 24 May 2010 10:55:59 +0900 Subject: [PATCH] watchdog: shwdt: Kill off mmap stub and superfluous comments. The wdt mmaping thing was a special-cased hack that nothing in the wild depends on, so just kill it off. While at it, sanitize the superfluous comments in preparation for a driver rewrite and overhauled interface. Signed-off-by: Paul Mundt --- drivers/watchdog/Kconfig | 8 --- drivers/watchdog/shwdt.c | 138 +-------------------------------------- 2 files changed, 2 insertions(+), 144 deletions(-) diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index b87ba23442d2..8828d8ffd353 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -948,14 +948,6 @@ config SH_WDT To compile this driver as a module, choose M here: the module will be called shwdt. -config SH_WDT_MMAP - bool "Allow mmap of SH WDT" - default n - depends on SH_WDT - help - If you say Y here, user applications will be able to mmap the - WDT/CPG registers. - # SPARC Architecture # SPARC64 Architecture diff --git a/drivers/watchdog/shwdt.c b/drivers/watchdog/shwdt.c index a03f84e5ee1f..bee1f5865825 100644 --- a/drivers/watchdog/shwdt.c +++ b/drivers/watchdog/shwdt.c @@ -1,9 +1,9 @@ /* - * drivers/char/watchdog/shwdt.c + * drivers/watchdog/shwdt.c * * Watchdog driver for integrated watchdog in the SuperH processors. * - * Copyright (C) 2001, 2002, 2003 Paul Mundt + * Copyright (C) 2001 - 2010 Paul Mundt * * 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 @@ -76,14 +76,8 @@ static DEFINE_SPINLOCK(shwdt_lock); #define WATCHDOG_HEARTBEAT 30 /* 30 sec default heartbeat */ static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */ - static int nowayout = WATCHDOG_NOWAYOUT; -/** - * sh_wdt_start - Start the Watchdog - * - * Starts the watchdog. - */ static void sh_wdt_start(void) { __u8 csr; @@ -114,15 +108,6 @@ static void sh_wdt_start(void) sh_wdt_write_csr(csr); #ifdef CONFIG_CPU_SH2 - /* - * Whoever came up with the RSTCSR semantics must've been smoking - * some of the good stuff, since in addition to the WTCSR/WTCNT write - * brain-damage, it's managed to fuck things up one step further.. - * - * If we need to clear the WOVF bit, the upper byte has to be 0xa5.. - * but if we want to touch RSTE or RSTS, the upper byte has to be - * 0x5a.. - */ csr = sh_wdt_read_rstcsr(); csr &= ~RSTCSR_RSTS; sh_wdt_write_rstcsr(csr); @@ -130,10 +115,6 @@ static void sh_wdt_start(void) spin_unlock_irqrestore(&shwdt_lock, flags); } -/** - * sh_wdt_stop - Stop the Watchdog - * Stops the watchdog. - */ static void sh_wdt_stop(void) { __u8 csr; @@ -149,10 +130,6 @@ static void sh_wdt_stop(void) spin_unlock_irqrestore(&shwdt_lock, flags); } -/** - * sh_wdt_keepalive - Keep the Userspace Watchdog Alive - * The Userspace watchdog got a KeepAlive: schedule the next heartbeat. - */ static inline void sh_wdt_keepalive(void) { unsigned long flags; @@ -162,10 +139,6 @@ static inline void sh_wdt_keepalive(void) spin_unlock_irqrestore(&shwdt_lock, flags); } -/** - * sh_wdt_set_heartbeat - Set the Userspace Watchdog heartbeat - * Set the Userspace Watchdog heartbeat - */ static int sh_wdt_set_heartbeat(int t) { unsigned long flags; @@ -179,12 +152,6 @@ static int sh_wdt_set_heartbeat(int t) return 0; } -/** - * sh_wdt_ping - Ping the Watchdog - * @data: Unused - * - * Clears overflow bit, resets timer counter. - */ static void sh_wdt_ping(unsigned long data) { unsigned long flags; @@ -206,13 +173,6 @@ static void sh_wdt_ping(unsigned long data) spin_unlock_irqrestore(&shwdt_lock, flags); } -/** - * sh_wdt_open - Open the Device - * @inode: inode of device - * @file: file handle of device - * - * Watchdog device is opened and started. - */ static int sh_wdt_open(struct inode *inode, struct file *file) { if (test_and_set_bit(0, &shwdt_is_open)) @@ -225,13 +185,6 @@ static int sh_wdt_open(struct inode *inode, struct file *file) return nonseekable_open(inode, file); } -/** - * sh_wdt_close - Close the Device - * @inode: inode of device - * @file: file handle of device - * - * Watchdog device is closed and stopped. - */ static int sh_wdt_close(struct inode *inode, struct file *file) { if (shwdt_expect_close == 42) { @@ -248,15 +201,6 @@ static int sh_wdt_close(struct inode *inode, struct file *file) return 0; } -/** - * sh_wdt_write - Write to Device - * @file: file handle of device - * @buf: buffer to write - * @count: length of buffer - * @ppos: offset - * - * Pings the watchdog on write. - */ static ssize_t sh_wdt_write(struct file *file, const char *buf, size_t count, loff_t *ppos) { @@ -280,64 +224,6 @@ static ssize_t sh_wdt_write(struct file *file, const char *buf, return count; } -/** - * sh_wdt_mmap - map WDT/CPG registers into userspace - * @file: file structure for the device - * @vma: VMA to map the registers into - * - * A simple mmap() implementation for the corner cases where the counter - * needs to be mapped in userspace directly. Due to the relatively small - * size of the area, neighbouring registers not necessarily tied to the - * CPG will also be accessible through the register page, so this remains - * configurable for users that really know what they're doing. - * - * Additionaly, the register page maps in the CPG register base relative - * to the nearest page-aligned boundary, which requires that userspace do - * the appropriate CPU subtype math for calculating the page offset for - * the counter value. - */ -static int sh_wdt_mmap(struct file *file, struct vm_area_struct *vma) -{ - int ret = -ENOSYS; - -#ifdef CONFIG_SH_WDT_MMAP - unsigned long addr; - - /* Only support the simple cases where we map in a register page. */ - if (((vma->vm_end - vma->vm_start) != PAGE_SIZE) || vma->vm_pgoff) - return -EINVAL; - - /* - * Pick WTCNT as the start, it's usually the first register after the - * FRQCR, and neither one are generally page-aligned out of the box. - */ - addr = WTCNT & ~(PAGE_SIZE - 1); - - vma->vm_flags |= VM_IO; - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - - if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT, - PAGE_SIZE, vma->vm_page_prot)) { - printk(KERN_ERR PFX "%s: io_remap_pfn_range failed\n", - __func__); - return -EAGAIN; - } - - ret = 0; -#endif - - return ret; -} - -/** - * sh_wdt_ioctl - Query Device - * @file: file handle of device - * @cmd: watchdog command - * @arg: argument - * - * Query basic information from the device or ping it, as outlined by the - * watchdog API. - */ static long sh_wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -386,15 +272,6 @@ static long sh_wdt_ioctl(struct file *file, unsigned int cmd, return 0; } -/** - * sh_wdt_notify_sys - Notifier Handler - * @this: notifier block - * @code: notifier event - * @unused: unused - * - * Handles specific events, such as turning off the watchdog during a - * shutdown event. - */ static int sh_wdt_notify_sys(struct notifier_block *this, unsigned long code, void *unused) { @@ -411,7 +288,6 @@ static const struct file_operations sh_wdt_fops = { .unlocked_ioctl = sh_wdt_ioctl, .open = sh_wdt_open, .release = sh_wdt_close, - .mmap = sh_wdt_mmap, }; static const struct watchdog_info sh_wdt_info = { @@ -431,11 +307,6 @@ static struct miscdevice sh_wdt_miscdev = { .fops = &sh_wdt_fops, }; -/** - * sh_wdt_init - Initialize module - * Registers the device and notifier handler. Actual device - * initialization is handled by sh_wdt_open(). - */ static int __init sh_wdt_init(void) { int rc; @@ -477,11 +348,6 @@ static int __init sh_wdt_init(void) return 0; } -/** - * sh_wdt_exit - Deinitialize module - * Unregisters the device and notifier handler. Actual device - * deinitialization is handled by sh_wdt_close(). - */ static void __exit sh_wdt_exit(void) { misc_deregister(&sh_wdt_miscdev); -- 2.34.1