android_kernel_xiaomi_sm8350/drivers/rtc/class.c

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/*
* RTC subsystem, base class
*
* Copyright (C) 2005 Tower Technologies
* Author: Alessandro Zummo <a.zummo@towertech.it>
*
* class skeleton from drivers/hwmon/hwmon.c
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/kdev_t.h>
#include <linux/idr.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 04:04:11 -04:00
#include <linux/slab.h>
#include "rtc-core.h"
static DEFINE_IDR(rtc_idr);
static DEFINE_MUTEX(idr_lock);
struct class *rtc_class;
static void rtc_device_release(struct device *dev)
{
struct rtc_device *rtc = to_rtc_device(dev);
mutex_lock(&idr_lock);
idr_remove(&rtc_idr, rtc->id);
mutex_unlock(&idr_lock);
kfree(rtc);
}
#if defined(CONFIG_PM) && defined(CONFIG_RTC_HCTOSYS_DEVICE)
/*
* On suspend(), measure the delta between one RTC and the
* system's wall clock; restore it on resume().
*/
static struct timespec delta;
static time_t oldtime;
static int rtc_suspend(struct device *dev, pm_message_t mesg)
{
struct rtc_device *rtc = to_rtc_device(dev);
struct rtc_time tm;
struct timespec ts = current_kernel_time();
if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
return 0;
rtc_read_time(rtc, &tm);
rtc_tm_to_time(&tm, &oldtime);
/* RTC precision is 1 second; adjust delta for avg 1/2 sec err */
set_normalized_timespec(&delta,
ts.tv_sec - oldtime,
ts.tv_nsec - (NSEC_PER_SEC >> 1));
return 0;
}
static int rtc_resume(struct device *dev)
{
struct rtc_device *rtc = to_rtc_device(dev);
struct rtc_time tm;
time_t newtime;
struct timespec time;
if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
return 0;
rtc_read_time(rtc, &tm);
if (rtc_valid_tm(&tm) != 0) {
pr_debug("%s: bogus resume time\n", dev_name(&rtc->dev));
return 0;
}
rtc_tm_to_time(&tm, &newtime);
if (newtime <= oldtime) {
if (newtime < oldtime)
pr_debug("%s: time travel!\n", dev_name(&rtc->dev));
return 0;
}
/* restore wall clock using delta against this RTC;
* adjust again for avg 1/2 second RTC sampling error
*/
set_normalized_timespec(&time,
newtime + delta.tv_sec,
(NSEC_PER_SEC >> 1) + delta.tv_nsec);
do_settimeofday(&time);
return 0;
}
#else
#define rtc_suspend NULL
#define rtc_resume NULL
#endif
/**
* rtc_device_register - register w/ RTC class
* @dev: the device to register
*
* rtc_device_unregister() must be called when the class device is no
* longer needed.
*
* Returns the pointer to the new struct class device.
*/
struct rtc_device *rtc_device_register(const char *name, struct device *dev,
const struct rtc_class_ops *ops,
struct module *owner)
{
struct rtc_device *rtc;
int id, err;
if (idr_pre_get(&rtc_idr, GFP_KERNEL) == 0) {
err = -ENOMEM;
goto exit;
}
mutex_lock(&idr_lock);
err = idr_get_new(&rtc_idr, NULL, &id);
mutex_unlock(&idr_lock);
if (err < 0)
goto exit;
id = id & MAX_ID_MASK;
rtc = kzalloc(sizeof(struct rtc_device), GFP_KERNEL);
if (rtc == NULL) {
err = -ENOMEM;
goto exit_idr;
}
rtc->id = id;
rtc->ops = ops;
rtc->owner = owner;
rtc->max_user_freq = 64;
rtc->dev.parent = dev;
rtc->dev.class = rtc_class;
rtc->dev.release = rtc_device_release;
mutex_init(&rtc->ops_lock);
spin_lock_init(&rtc->irq_lock);
spin_lock_init(&rtc->irq_task_lock);
init_waitqueue_head(&rtc->irq_queue);
strlcpy(rtc->name, name, RTC_DEVICE_NAME_SIZE);
dev_set_name(&rtc->dev, "rtc%d", id);
rtc_dev_prepare(rtc);
err = device_register(&rtc->dev);
if (err) {
put_device(&rtc->dev);
goto exit_kfree;
}
rtc_dev_add_device(rtc);
rtc_sysfs_add_device(rtc);
rtc_proc_add_device(rtc);
dev_info(dev, "rtc core: registered %s as %s\n",
rtc->name, dev_name(&rtc->dev));
return rtc;
exit_kfree:
kfree(rtc);
exit_idr:
mutex_lock(&idr_lock);
idr_remove(&rtc_idr, id);
mutex_unlock(&idr_lock);
exit:
dev_err(dev, "rtc core: unable to register %s, err = %d\n",
name, err);
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(rtc_device_register);
/**
* rtc_device_unregister - removes the previously registered RTC class device
*
* @rtc: the RTC class device to destroy
*/
void rtc_device_unregister(struct rtc_device *rtc)
{
if (get_device(&rtc->dev) != NULL) {
mutex_lock(&rtc->ops_lock);
/* remove innards of this RTC, then disable it, before
* letting any rtc_class_open() users access it again
*/
rtc_sysfs_del_device(rtc);
rtc_dev_del_device(rtc);
rtc_proc_del_device(rtc);
device_unregister(&rtc->dev);
rtc->ops = NULL;
mutex_unlock(&rtc->ops_lock);
put_device(&rtc->dev);
}
}
EXPORT_SYMBOL_GPL(rtc_device_unregister);
static int __init rtc_init(void)
{
rtc_class = class_create(THIS_MODULE, "rtc");
if (IS_ERR(rtc_class)) {
printk(KERN_ERR "%s: couldn't create class\n", __FILE__);
return PTR_ERR(rtc_class);
}
rtc_class->suspend = rtc_suspend;
rtc_class->resume = rtc_resume;
rtc_dev_init();
rtc_sysfs_init(rtc_class);
return 0;
}
static void __exit rtc_exit(void)
{
rtc_dev_exit();
class_destroy(rtc_class);
idr_destroy(&rtc_idr);
}
subsys_initcall(rtc_init);
module_exit(rtc_exit);
MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("RTC class support");
MODULE_LICENSE("GPL");