* [PATCH 2/2] [v2] powerpc/watchdog: allow the e500 watchdog driver to be compiled as a module
2010-09-20 16:23 [PATCH 1/2] [v2] powerpc: export ppc_proc_freq and ppc_tb_freq as GPL symbols Timur Tabi
@ 2010-09-20 16:23 ` Timur Tabi
2010-10-07 6:00 ` Kumar Gala
2010-09-20 19:30 ` [PATCH 1/2] [v2] powerpc: export ppc_proc_freq and ppc_tb_freq as GPL symbols Josh Boyer
2010-10-07 5:59 ` Kumar Gala
2 siblings, 1 reply; 5+ messages in thread
From: Timur Tabi @ 2010-09-20 16:23 UTC (permalink / raw)
To: benh, linuxppc-dev, kumar.gala, linux-watchdog, jwboyer
Register the __init and __exit functions in the PowerPC e500 watchdog driver
as module entry/exit functions, and modify the Kconfig entry.
Add a .release method for the PowerPC e500 watchdog driver, so that the
watchdog is disabled when the driver is closed.
Loosely based on original code from Jiang Yutang <b14898@freescale.com>.
Signed-off-by: Timur Tabi <timur@freescale.com>
---
This patch requires:
powerpc: export ppc_proc_freq and ppc_tb_freq as GPL symbols
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 24efd8e..a6812eb 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 3d49671..a989998 100644
--- a/drivers/watchdog/booke_wdt.c
+++ b/drivers/watchdog/booke_wdt.c
@@ -4,7 +4,7 @@
* Author: Matthew McClintock
* Maintainer: Kumar Gala <galak@kernel.crashing.org>
*
- * 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");
--
1.7.2.3
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH 1/2] [v2] powerpc: export ppc_proc_freq and ppc_tb_freq as GPL symbols
2010-09-20 16:23 [PATCH 1/2] [v2] powerpc: export ppc_proc_freq and ppc_tb_freq as GPL symbols Timur Tabi
2010-09-20 16:23 ` [PATCH 2/2] [v2] powerpc/watchdog: allow the e500 watchdog driver to be compiled as a module Timur Tabi
@ 2010-09-20 19:30 ` Josh Boyer
2010-10-07 5:59 ` Kumar Gala
2 siblings, 0 replies; 5+ messages in thread
From: Josh Boyer @ 2010-09-20 19:30 UTC (permalink / raw)
To: Timur Tabi; +Cc: kumar.gala, linux-watchdog, linuxppc-dev
On Mon, Sep 20, 2010 at 11:23:41AM -0500, Timur Tabi wrote:
>Export the global variable 'ppc_tb_freq', so that modules (like the Book-E
>watchdog driver) can use it. To maintain consistency, ppc_proc_freq is changed
>to a GPL-only export. This is okay, because any module that needs this symbol
>should be an actual Linux driver, which must be GPL-licensed.
>
>Signed-off-by: Timur Tabi <timur@freescale.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
>---
>
>This export is necessary for the Book-E watchdog driver to be compiled as a
>module.
>
> arch/powerpc/kernel/time.c | 3 ++-
> 1 files changed, 2 insertions(+), 1 deletions(-)
>
>diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
>index 8533b3b..0c0c241 100644
>--- a/arch/powerpc/kernel/time.c
>+++ b/arch/powerpc/kernel/time.c
>@@ -161,8 +161,9 @@ extern struct timezone sys_tz;
> static long timezone_offset;
>
> unsigned long ppc_proc_freq;
>-EXPORT_SYMBOL(ppc_proc_freq);
>+EXPORT_SYMBOL_GPL(ppc_proc_freq);
> unsigned long ppc_tb_freq;
>+EXPORT_SYMBOL_GPL(ppc_tb_freq);
>
> static DEFINE_PER_CPU(u64, last_jiffy);
>
>--
>1.7.2.3
>
>
>_______________________________________________
>Linuxppc-dev mailing list
>Linuxppc-dev@lists.ozlabs.org
>https://lists.ozlabs.org/listinfo/linuxppc-dev
^ permalink raw reply [flat|nested] 5+ messages in thread