From fbdd7144ceadd578bc2a875af1dabd67e80ba0d0 Mon Sep 17 00:00:00 2001 From: Timur Tabi Date: Mon, 20 Sep 2010 11:23:42 -0500 Subject: [PATCH] powerpc/watchdog: Allow the Book-E driver to be compiled as a module Register the __init and __exit functions in the PowerPC Book-E Watchdog driver as module entry/exit functions, and modify the Kconfig entry. Add a .release method for the PowerPC Book-E Watchdog driver, so that the watchdog is disabled when the driver is closed. Loosely based on original code from Jiang Yutang . Signed-off-by: Timur Tabi Signed-off-by: Kumar Gala --- drivers/watchdog/Kconfig | 5 ++++- drivers/watchdog/booke_wdt.c | 39 ++++++++++++++++++++++++++++++++++-- 2 files changed, 41 insertions(+), 3 deletions(-) diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 24efd8ea41bb..a6812eb31fa1 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -957,9 +957,12 @@ config PIKA_WDT the Warp platform. config BOOKE_WDT - bool "PowerPC Book-E Watchdog Timer" + tristate "PowerPC Book-E Watchdog Timer" depends on BOOKE || 4xx ---help--- + Watchdog driver for PowerPC Book-E chips, such as the Freescale + MPC85xx SOCs and the IBM PowerPC 440. + Please see Documentation/watchdog/watchdog-api.txt for more information. diff --git a/drivers/watchdog/booke_wdt.c b/drivers/watchdog/booke_wdt.c index 3d49671cdf5a..a9899981fd97 100644 --- a/drivers/watchdog/booke_wdt.c +++ b/drivers/watchdog/booke_wdt.c @@ -4,7 +4,7 @@ * Author: Matthew McClintock * Maintainer: Kumar Gala * - * Copyright 2005, 2008 Freescale Semiconductor Inc. + * Copyright 2005, 2008, 2010 Freescale Semiconductor Inc. * * 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 @@ -114,6 +114,27 @@ static void __booke_wdt_enable(void *data) mtspr(SPRN_TCR, val); } +/** + * booke_wdt_disable - disable the watchdog on the given CPU + * + * This function is called on each CPU. It disables the watchdog on that CPU. + * + * TCR[WRC] cannot be changed once it has been set to non-zero, but we can + * effectively disable the watchdog by setting its period to the maximum value. + */ +static void __booke_wdt_disable(void *data) +{ + u32 val; + + val = mfspr(SPRN_TCR); + val &= ~(TCR_WIE | WDTP_MASK); + mtspr(SPRN_TCR, val); + + /* clear status to make sure nothing is pending */ + __booke_wdt_ping(NULL); + +} + static ssize_t booke_wdt_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { @@ -193,12 +214,21 @@ static int booke_wdt_open(struct inode *inode, struct file *file) return nonseekable_open(inode, file); } +static int booke_wdt_release(struct inode *inode, struct file *file) +{ + on_each_cpu(__booke_wdt_disable, NULL, 0); + booke_wdt_enabled = 0; + + return 0; +} + static const struct file_operations booke_wdt_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .write = booke_wdt_write, .unlocked_ioctl = booke_wdt_ioctl, .open = booke_wdt_open, + .release = booke_wdt_release, }; static struct miscdevice booke_wdt_miscdev = { @@ -237,4 +267,9 @@ static int __init booke_wdt_init(void) return ret; } -device_initcall(booke_wdt_init); + +module_init(booke_wdt_init); +module_exit(booke_wdt_exit); + +MODULE_DESCRIPTION("PowerPC Book-E watchdog driver"); +MODULE_LICENSE("GPL");