linux/drivers/watchdog/omap_wdt.c

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/*
* omap_wdt.c
*
* Watchdog driver for the TI OMAP 16xx & 24xx/34xx 32KHz (non-secure) watchdog
*
* Author: MontaVista Software, Inc.
* <gdavis@mvista.com> or <source@mvista.com>
*
* 2003 (c) MontaVista Software, Inc. This file is licensed under the
* terms of the GNU General Public License version 2. This program is
* licensed "as is" without any warranty of any kind, whether express
* or implied.
*
* History:
*
* 20030527: George G. Davis <gdavis@mvista.com>
* Initially based on linux-2.4.19-rmk7-pxa1/drivers/char/sa1100_wdt.c
* (c) Copyright 2000 Oleg Drokin <green@crimea.edu>
* Based on SoftDog driver by Alan Cox <alan@lxorguk.ukuu.org.uk>
*
* Copyright (c) 2004 Texas Instruments.
* 1. Modified to support OMAP1610 32-KHz watchdog timer
* 2. Ported to 2.6 kernel
*
* Copyright (c) 2005 David Brownell
* Use the driver model and standard identifiers; handle bigger timeouts.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/moduleparam.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <linux/uaccess.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <mach/hardware.h>
ARM: OMAP: Split plat/hardware.h, use local soc.h for omap2+ As the plat and mach includes need to disappear for single zImage work, we need to remove plat/hardware.h. Do this by splitting plat/hardware.h into omap1 and omap2+ specific files. The old plat/hardware.h already has omap1 only defines, so it gets moved to mach/hardware.h for omap1. For omap2+, we use the local soc.h that for now just includes the related SoC headers to keep this patch more readable. Note that the local soc.h still includes plat/cpu.h that can be dealt with in later patches. Let's also include plat/serial.h from common.h for all the board-*.c files. This allows making the include files local later on without patching these files again. Note that only minimal changes are done in this patch for the drivers/watchdog/omap_wdt.c driver to keep things compiling. Further patches are needed to eventually remove cpu_is_omap usage in the drivers. Also only minimal changes are done to sound/soc/omap/* to remove the unneeded includes and to define OMAP44XX_MCPDM_L3_BASE locally so there's no need to include omap44xx.h. While at it, also sort some of the includes in the standard way. Cc: linux-watchdog@vger.kernel.org Cc: alsa-devel@alsa-project.org Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> Cc: Jarkko Nikula <jarkko.nikula@bitmer.com> Cc: Liam Girdwood <lrg@ti.com> Acked-by: Wim Van Sebroeck <wim@iguana.be> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-09-01 01:59:07 +08:00
#include <plat/cpu.h>
#include <plat/prcm.h>
#include "omap_wdt.h"
static struct platform_device *omap_wdt_dev;
static unsigned timer_margin;
module_param(timer_margin, uint, 0);
MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)");
static unsigned int wdt_trgr_pattern = 0x1234;
static DEFINE_SPINLOCK(wdt_lock);
struct omap_wdt_dev {
void __iomem *base; /* physical */
struct device *dev;
int omap_wdt_users;
struct resource *mem;
struct miscdevice omap_wdt_miscdev;
};
static void omap_wdt_ping(struct omap_wdt_dev *wdev)
{
void __iomem *base = wdev->base;
/* wait for posted write to complete */
while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08)
cpu_relax();
wdt_trgr_pattern = ~wdt_trgr_pattern;
__raw_writel(wdt_trgr_pattern, (base + OMAP_WATCHDOG_TGR));
/* wait for posted write to complete */
while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08)
cpu_relax();
/* reloaded WCRR from WLDR */
}
static void omap_wdt_enable(struct omap_wdt_dev *wdev)
{
void __iomem *base = wdev->base;
/* Sequence to enable the watchdog */
__raw_writel(0xBBBB, base + OMAP_WATCHDOG_SPR);
while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x10)
cpu_relax();
__raw_writel(0x4444, base + OMAP_WATCHDOG_SPR);
while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x10)
cpu_relax();
}
static void omap_wdt_disable(struct omap_wdt_dev *wdev)
{
void __iomem *base = wdev->base;
/* sequence required to disable watchdog */
__raw_writel(0xAAAA, base + OMAP_WATCHDOG_SPR); /* TIMER_MODE */
while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x10)
cpu_relax();
__raw_writel(0x5555, base + OMAP_WATCHDOG_SPR); /* TIMER_MODE */
while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x10)
cpu_relax();
}
static void omap_wdt_adjust_timeout(unsigned new_timeout)
{
if (new_timeout < TIMER_MARGIN_MIN)
new_timeout = TIMER_MARGIN_DEFAULT;
if (new_timeout > TIMER_MARGIN_MAX)
new_timeout = TIMER_MARGIN_MAX;
timer_margin = new_timeout;
}
static void omap_wdt_set_timeout(struct omap_wdt_dev *wdev)
{
u32 pre_margin = GET_WLDR_VAL(timer_margin);
void __iomem *base = wdev->base;
/* just count up at 32 KHz */
while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x04)
cpu_relax();
__raw_writel(pre_margin, base + OMAP_WATCHDOG_LDR);
while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x04)
cpu_relax();
}
/*
* Allow only one task to hold it open
*/
static int omap_wdt_open(struct inode *inode, struct file *file)
{
struct omap_wdt_dev *wdev = platform_get_drvdata(omap_wdt_dev);
void __iomem *base = wdev->base;
if (test_and_set_bit(1, (unsigned long *)&(wdev->omap_wdt_users)))
return -EBUSY;
pm_runtime_get_sync(wdev->dev);
/* initialize prescaler */
while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
cpu_relax();
__raw_writel((1 << 5) | (PTV << 2), base + OMAP_WATCHDOG_CNTRL);
while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
cpu_relax();
file->private_data = (void *) wdev;
omap_wdt_set_timeout(wdev);
omap_wdt_ping(wdev); /* trigger loading of new timeout value */
omap_wdt_enable(wdev);
return nonseekable_open(inode, file);
}
static int omap_wdt_release(struct inode *inode, struct file *file)
{
struct omap_wdt_dev *wdev = file->private_data;
/*
* Shut off the timer unless NOWAYOUT is defined.
*/
#ifndef CONFIG_WATCHDOG_NOWAYOUT
omap_wdt_disable(wdev);
pm_runtime_put_sync(wdev->dev);
#else
pr_crit("Unexpected close, not stopping!\n");
#endif
wdev->omap_wdt_users = 0;
return 0;
}
static ssize_t omap_wdt_write(struct file *file, const char __user *data,
size_t len, loff_t *ppos)
{
struct omap_wdt_dev *wdev = file->private_data;
/* Refresh LOAD_TIME. */
if (len) {
spin_lock(&wdt_lock);
omap_wdt_ping(wdev);
spin_unlock(&wdt_lock);
}
return len;
}
static long omap_wdt_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
struct omap_wdt_dev *wdev;
int new_margin;
static const struct watchdog_info ident = {
.identity = "OMAP Watchdog",
.options = WDIOF_SETTIMEOUT,
.firmware_version = 0,
};
wdev = file->private_data;
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user((struct watchdog_info __user *)arg, &ident,
sizeof(ident));
case WDIOC_GETSTATUS:
return put_user(0, (int __user *)arg);
case WDIOC_GETBOOTSTATUS:
ARM: OMAP: Split plat/hardware.h, use local soc.h for omap2+ As the plat and mach includes need to disappear for single zImage work, we need to remove plat/hardware.h. Do this by splitting plat/hardware.h into omap1 and omap2+ specific files. The old plat/hardware.h already has omap1 only defines, so it gets moved to mach/hardware.h for omap1. For omap2+, we use the local soc.h that for now just includes the related SoC headers to keep this patch more readable. Note that the local soc.h still includes plat/cpu.h that can be dealt with in later patches. Let's also include plat/serial.h from common.h for all the board-*.c files. This allows making the include files local later on without patching these files again. Note that only minimal changes are done in this patch for the drivers/watchdog/omap_wdt.c driver to keep things compiling. Further patches are needed to eventually remove cpu_is_omap usage in the drivers. Also only minimal changes are done to sound/soc/omap/* to remove the unneeded includes and to define OMAP44XX_MCPDM_L3_BASE locally so there's no need to include omap44xx.h. While at it, also sort some of the includes in the standard way. Cc: linux-watchdog@vger.kernel.org Cc: alsa-devel@alsa-project.org Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> Cc: Jarkko Nikula <jarkko.nikula@bitmer.com> Cc: Liam Girdwood <lrg@ti.com> Acked-by: Wim Van Sebroeck <wim@iguana.be> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-09-01 01:59:07 +08:00
#ifdef CONFIG_ARCH_OMAP1
if (cpu_is_omap16xx())
return put_user(__raw_readw(ARM_SYSST),
(int __user *)arg);
ARM: OMAP: Split plat/hardware.h, use local soc.h for omap2+ As the plat and mach includes need to disappear for single zImage work, we need to remove plat/hardware.h. Do this by splitting plat/hardware.h into omap1 and omap2+ specific files. The old plat/hardware.h already has omap1 only defines, so it gets moved to mach/hardware.h for omap1. For omap2+, we use the local soc.h that for now just includes the related SoC headers to keep this patch more readable. Note that the local soc.h still includes plat/cpu.h that can be dealt with in later patches. Let's also include plat/serial.h from common.h for all the board-*.c files. This allows making the include files local later on without patching these files again. Note that only minimal changes are done in this patch for the drivers/watchdog/omap_wdt.c driver to keep things compiling. Further patches are needed to eventually remove cpu_is_omap usage in the drivers. Also only minimal changes are done to sound/soc/omap/* to remove the unneeded includes and to define OMAP44XX_MCPDM_L3_BASE locally so there's no need to include omap44xx.h. While at it, also sort some of the includes in the standard way. Cc: linux-watchdog@vger.kernel.org Cc: alsa-devel@alsa-project.org Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> Cc: Jarkko Nikula <jarkko.nikula@bitmer.com> Cc: Liam Girdwood <lrg@ti.com> Acked-by: Wim Van Sebroeck <wim@iguana.be> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-09-01 01:59:07 +08:00
#endif
#ifdef CONFIG_ARCH_OMAP2PLUS
if (cpu_is_omap24xx())
return put_user(omap_prcm_get_reset_sources(),
(int __user *)arg);
ARM: OMAP: Split plat/hardware.h, use local soc.h for omap2+ As the plat and mach includes need to disappear for single zImage work, we need to remove plat/hardware.h. Do this by splitting plat/hardware.h into omap1 and omap2+ specific files. The old plat/hardware.h already has omap1 only defines, so it gets moved to mach/hardware.h for omap1. For omap2+, we use the local soc.h that for now just includes the related SoC headers to keep this patch more readable. Note that the local soc.h still includes plat/cpu.h that can be dealt with in later patches. Let's also include plat/serial.h from common.h for all the board-*.c files. This allows making the include files local later on without patching these files again. Note that only minimal changes are done in this patch for the drivers/watchdog/omap_wdt.c driver to keep things compiling. Further patches are needed to eventually remove cpu_is_omap usage in the drivers. Also only minimal changes are done to sound/soc/omap/* to remove the unneeded includes and to define OMAP44XX_MCPDM_L3_BASE locally so there's no need to include omap44xx.h. While at it, also sort some of the includes in the standard way. Cc: linux-watchdog@vger.kernel.org Cc: alsa-devel@alsa-project.org Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> Cc: Jarkko Nikula <jarkko.nikula@bitmer.com> Cc: Liam Girdwood <lrg@ti.com> Acked-by: Wim Van Sebroeck <wim@iguana.be> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-09-01 01:59:07 +08:00
#endif
return put_user(0, (int __user *)arg);
case WDIOC_KEEPALIVE:
spin_lock(&wdt_lock);
omap_wdt_ping(wdev);
spin_unlock(&wdt_lock);
return 0;
case WDIOC_SETTIMEOUT:
if (get_user(new_margin, (int __user *)arg))
return -EFAULT;
omap_wdt_adjust_timeout(new_margin);
spin_lock(&wdt_lock);
omap_wdt_disable(wdev);
omap_wdt_set_timeout(wdev);
omap_wdt_enable(wdev);
omap_wdt_ping(wdev);
spin_unlock(&wdt_lock);
/* Fall */
case WDIOC_GETTIMEOUT:
return put_user(timer_margin, (int __user *)arg);
default:
return -ENOTTY;
}
}
static const struct file_operations omap_wdt_fops = {
.owner = THIS_MODULE,
.write = omap_wdt_write,
.unlocked_ioctl = omap_wdt_ioctl,
.open = omap_wdt_open,
.release = omap_wdt_release,
llseek: automatically add .llseek fop All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-16 00:52:59 +08:00
.llseek = no_llseek,
};
static int __devinit omap_wdt_probe(struct platform_device *pdev)
{
struct resource *res, *mem;
struct omap_wdt_dev *wdev;
int ret;
/* reserve static register mappings */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
ret = -ENOENT;
goto err_get_resource;
}
if (omap_wdt_dev) {
ret = -EBUSY;
goto err_busy;
}
mem = request_mem_region(res->start, resource_size(res), pdev->name);
if (!mem) {
ret = -EBUSY;
goto err_busy;
}
wdev = kzalloc(sizeof(struct omap_wdt_dev), GFP_KERNEL);
if (!wdev) {
ret = -ENOMEM;
goto err_kzalloc;
}
wdev->omap_wdt_users = 0;
wdev->mem = mem;
wdev->dev = &pdev->dev;
wdev->base = ioremap(res->start, resource_size(res));
if (!wdev->base) {
ret = -ENOMEM;
goto err_ioremap;
}
platform_set_drvdata(pdev, wdev);
pm_runtime_enable(wdev->dev);
pm_runtime_get_sync(wdev->dev);
omap_wdt_disable(wdev);
omap_wdt_adjust_timeout(timer_margin);
wdev->omap_wdt_miscdev.parent = &pdev->dev;
wdev->omap_wdt_miscdev.minor = WATCHDOG_MINOR;
wdev->omap_wdt_miscdev.name = "watchdog";
wdev->omap_wdt_miscdev.fops = &omap_wdt_fops;
ret = misc_register(&(wdev->omap_wdt_miscdev));
if (ret)
goto err_misc;
pr_info("OMAP Watchdog Timer Rev 0x%02x: initial timeout %d sec\n",
__raw_readl(wdev->base + OMAP_WATCHDOG_REV) & 0xFF,
timer_margin);
pm_runtime_put_sync(wdev->dev);
omap_wdt_dev = pdev;
return 0;
err_misc:
pm_runtime_disable(wdev->dev);
platform_set_drvdata(pdev, NULL);
iounmap(wdev->base);
err_ioremap:
wdev->base = NULL;
kfree(wdev);
err_kzalloc:
release_mem_region(res->start, resource_size(res));
err_busy:
err_get_resource:
return ret;
}
static void omap_wdt_shutdown(struct platform_device *pdev)
{
struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
if (wdev->omap_wdt_users) {
omap_wdt_disable(wdev);
pm_runtime_put_sync(wdev->dev);
}
}
static int __devexit omap_wdt_remove(struct platform_device *pdev)
{
struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
pm_runtime_disable(wdev->dev);
if (!res)
return -ENOENT;
misc_deregister(&(wdev->omap_wdt_miscdev));
release_mem_region(res->start, resource_size(res));
platform_set_drvdata(pdev, NULL);
iounmap(wdev->base);
kfree(wdev);
omap_wdt_dev = NULL;
return 0;
}
#ifdef CONFIG_PM
/* REVISIT ... not clear this is the best way to handle system suspend; and
* it's very inappropriate for selective device suspend (e.g. suspending this
* through sysfs rather than by stopping the watchdog daemon). Also, this
* may not play well enough with NOWAYOUT...
*/
static int omap_wdt_suspend(struct platform_device *pdev, pm_message_t state)
{
struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
if (wdev->omap_wdt_users) {
omap_wdt_disable(wdev);
pm_runtime_put_sync(wdev->dev);
}
return 0;
}
static int omap_wdt_resume(struct platform_device *pdev)
{
struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
if (wdev->omap_wdt_users) {
pm_runtime_get_sync(wdev->dev);
omap_wdt_enable(wdev);
omap_wdt_ping(wdev);
}
return 0;
}
#else
#define omap_wdt_suspend NULL
#define omap_wdt_resume NULL
#endif
static const struct of_device_id omap_wdt_of_match[] = {
{ .compatible = "ti,omap3-wdt", },
{},
};
MODULE_DEVICE_TABLE(of, omap_wdt_of_match);
static struct platform_driver omap_wdt_driver = {
.probe = omap_wdt_probe,
.remove = __devexit_p(omap_wdt_remove),
.shutdown = omap_wdt_shutdown,
.suspend = omap_wdt_suspend,
.resume = omap_wdt_resume,
.driver = {
.owner = THIS_MODULE,
.name = "omap_wdt",
.of_match_table = omap_wdt_of_match,
},
};
module_platform_driver(omap_wdt_driver);
MODULE_AUTHOR("George G. Davis");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS("platform:omap_wdt");