p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

rtc: class: reimplement devm_rtc_device_register 

Implement devm_rtc_device_register using devm_rtc_allocate_device and
__rtc_register_device so there is only one path left to register rtc
devices.

Also mark it as deprecated so new drivers will hopefully use
devm_rtc_allocate_device and rtc_register_device that are less race prone
and allow avoiding the 2038, 2070, 2100 and 2106 bugs properly.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Alexandre Belloni 2018-12-18 22:15:58 +01:00
parent 9a03201170
commit a269441493
1 changed files with 36 additions and 121 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

157
drivers/rtc/class.c
View File

@ -277,82 +277,6 @@ static void rtc_device_get_offset(struct rtc_device *rtc)
rtc->offset_secs = 0;
}
/**
* 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.
*/
static 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;
struct rtc_wkalrm alrm;
int id, err;
id = rtc_device_get_id(dev);
if (id < 0) {
err = id;
goto exit;
}
rtc = rtc_allocate_device();
if (!rtc) {
err = -ENOMEM;
goto exit_ida;
}
rtc->id = id;
rtc->ops = ops;
rtc->owner = owner;
rtc->dev.parent = dev;
dev_set_name(&rtc->dev, "rtc%d", id);
rtc_device_get_offset(rtc);
/* Check to see if there is an ALARM already set in hw */
err = __rtc_read_alarm(rtc, &alrm);
if (!err && !rtc_valid_tm(&alrm.time))
rtc_initialize_alarm(rtc, &alrm);
rtc_dev_prepare(rtc);
err = cdev_device_add(&rtc->char_dev, &rtc->dev);
if (err) {
dev_warn(&rtc->dev, "%s: failed to add char device %d:%d\n",
name, MAJOR(rtc->dev.devt), rtc->id);
/* This will free both memory and the ID */
put_device(&rtc->dev);
goto exit;
} else {
dev_dbg(&rtc->dev, "%s: dev (%d:%d)\n", name,
MAJOR(rtc->dev.devt), rtc->id);
}
rtc_proc_add_device(rtc);
dev_info(dev, "rtc core: registered %s as %s\n",
name, dev_name(&rtc->dev));
return rtc;
exit_ida:
ida_simple_remove(&rtc_ida, id);
exit:
dev_err(dev, "rtc core: unable to register %s, err = %d\n",
name, err);
return ERR_PTR(err);
}
/**
* rtc_device_unregister - removes the previously registered RTC class device
*
@ -372,51 +296,6 @@ static void rtc_device_unregister(struct rtc_device *rtc)
put_device(&rtc->dev);
}
static void devm_rtc_device_release(struct device *dev, void *res)
{
struct rtc_device *rtc = *(struct rtc_device **)res;
rtc_nvmem_unregister(rtc);
rtc_device_unregister(rtc);
}
/**
* devm_rtc_device_register - resource managed rtc_device_register()
* @dev: the device to register
* @name: the name of the device
* @ops: the rtc operations structure
* @owner: the module owner
*
* @return a struct rtc on success, or an ERR_PTR on error
*
* Managed rtc_device_register(). The rtc_device returned from this function
* are automatically freed on driver detach. See rtc_device_register()
* for more information.
*/
struct rtc_device *devm_rtc_device_register(struct device *dev,
const char *name,
const struct rtc_class_ops *ops,
struct module *owner)
{
struct rtc_device **ptr, *rtc;
ptr = devres_alloc(devm_rtc_device_release, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
rtc = rtc_device_register(name, dev, ops, owner);
if (!IS_ERR(rtc)) {
*ptr = rtc;
devres_add(dev, ptr);
} else {
devres_free(ptr);
}
return rtc;
}
EXPORT_SYMBOL_GPL(devm_rtc_device_register);
static void devm_rtc_release_device(struct device *dev, void *res)
{
struct rtc_device *rtc = *(struct rtc_device **)res;
@ -503,6 +382,42 @@ int __rtc_register_device(struct module *owner, struct rtc_device *rtc)
}
EXPORT_SYMBOL_GPL(__rtc_register_device);
/**
* devm_rtc_device_register - resource managed rtc_device_register()
* @dev: the device to register
* @name: the name of the device (unused)
* @ops: the rtc operations structure
* @owner: the module owner
*
* @return a struct rtc on success, or an ERR_PTR on error
*
* Managed rtc_device_register(). The rtc_device returned from this function
* are automatically freed on driver detach.
* This function is deprecated, use devm_rtc_allocate_device and
* rtc_register_device instead
*/
struct rtc_device *devm_rtc_device_register(struct device *dev,
const char *name,
const struct rtc_class_ops *ops,
struct module *owner)
{
struct rtc_device *rtc;
int err;
rtc = devm_rtc_allocate_device(dev);
if (IS_ERR(rtc))
return rtc;
rtc->ops = ops;
err = __rtc_register_device(owner, rtc);
if (err)
return ERR_PTR(err);
return rtc;
}
EXPORT_SYMBOL_GPL(devm_rtc_device_register);
static int __init rtc_init(void)
{
rtc_class = class_create(THIS_MODULE, "rtc");