linux_dsm_epyc7002/drivers/media/v4l2-core/v4l2-async.c
Sakari Ailus 24def9b586 media: v4l: async: Register sub-devices before calling bound callback
Register the sub-device before calling the notifier's bound callback.
Doing this the other way around is problematic as the struct v4l2_device
has not assigned for the sub-device yet and may be required by the bound
callback.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-10-31 13:53:18 -04:00

369 lines
8.0 KiB
C

/*
* V4L2 asynchronous subdevice registration API
*
* Copyright (C) 2012-2013, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
*
* 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/device.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <media/v4l2-async.h>
#include <media/v4l2-device.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-subdev.h>
static int v4l2_async_notifier_call_bound(struct v4l2_async_notifier *n,
struct v4l2_subdev *subdev,
struct v4l2_async_subdev *asd)
{
if (!n->ops || !n->ops->bound)
return 0;
return n->ops->bound(n, subdev, asd);
}
static void v4l2_async_notifier_call_unbind(struct v4l2_async_notifier *n,
struct v4l2_subdev *subdev,
struct v4l2_async_subdev *asd)
{
if (!n->ops || !n->ops->unbind)
return;
n->ops->unbind(n, subdev, asd);
}
static int v4l2_async_notifier_call_complete(struct v4l2_async_notifier *n)
{
if (!n->ops || !n->ops->complete)
return 0;
return n->ops->complete(n);
}
static bool match_i2c(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd)
{
#if IS_ENABLED(CONFIG_I2C)
struct i2c_client *client = i2c_verify_client(sd->dev);
return client &&
asd->match.i2c.adapter_id == client->adapter->nr &&
asd->match.i2c.address == client->addr;
#else
return false;
#endif
}
static bool match_devname(struct v4l2_subdev *sd,
struct v4l2_async_subdev *asd)
{
return !strcmp(asd->match.device_name.name, dev_name(sd->dev));
}
static bool match_fwnode(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd)
{
return sd->fwnode == asd->match.fwnode.fwnode;
}
static bool match_custom(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd)
{
if (!asd->match.custom.match)
/* Match always */
return true;
return asd->match.custom.match(sd->dev, asd);
}
static LIST_HEAD(subdev_list);
static LIST_HEAD(notifier_list);
static DEFINE_MUTEX(list_lock);
static struct v4l2_async_subdev *v4l2_async_find_match(
struct v4l2_async_notifier *notifier, struct v4l2_subdev *sd)
{
bool (*match)(struct v4l2_subdev *, struct v4l2_async_subdev *);
struct v4l2_async_subdev *asd;
list_for_each_entry(asd, &notifier->waiting, list) {
/* bus_type has been verified valid before */
switch (asd->match_type) {
case V4L2_ASYNC_MATCH_CUSTOM:
match = match_custom;
break;
case V4L2_ASYNC_MATCH_DEVNAME:
match = match_devname;
break;
case V4L2_ASYNC_MATCH_I2C:
match = match_i2c;
break;
case V4L2_ASYNC_MATCH_FWNODE:
match = match_fwnode;
break;
default:
/* Cannot happen, unless someone breaks us */
WARN_ON(true);
return NULL;
}
/* match cannot be NULL here */
if (match(sd, asd))
return asd;
}
return NULL;
}
static int v4l2_async_match_notify(struct v4l2_async_notifier *notifier,
struct v4l2_subdev *sd,
struct v4l2_async_subdev *asd)
{
int ret;
ret = v4l2_device_register_subdev(notifier->v4l2_dev, sd);
if (ret < 0)
return ret;
ret = v4l2_async_notifier_call_bound(notifier, sd, asd);
if (ret < 0) {
v4l2_device_unregister_subdev(sd);
return ret;
}
/* Remove from the waiting list */
list_del(&asd->list);
sd->asd = asd;
sd->notifier = notifier;
/* Move from the global subdevice list to notifier's done */
list_move(&sd->async_list, &notifier->done);
return 0;
}
static void v4l2_async_cleanup(struct v4l2_subdev *sd)
{
v4l2_device_unregister_subdev(sd);
/* Subdevice driver will reprobe and put the subdev back onto the list */
list_del_init(&sd->async_list);
sd->asd = NULL;
}
static void v4l2_async_notifier_unbind_all_subdevs(
struct v4l2_async_notifier *notifier)
{
struct v4l2_subdev *sd, *tmp;
list_for_each_entry_safe(sd, tmp, &notifier->done, async_list) {
v4l2_async_notifier_call_unbind(notifier, sd, sd->asd);
v4l2_async_cleanup(sd);
list_move(&sd->async_list, &subdev_list);
}
}
int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
struct v4l2_async_notifier *notifier)
{
struct v4l2_subdev *sd, *tmp;
struct v4l2_async_subdev *asd;
int ret;
int i;
if (!v4l2_dev || !notifier->num_subdevs ||
notifier->num_subdevs > V4L2_MAX_SUBDEVS)
return -EINVAL;
notifier->v4l2_dev = v4l2_dev;
INIT_LIST_HEAD(&notifier->waiting);
INIT_LIST_HEAD(&notifier->done);
for (i = 0; i < notifier->num_subdevs; i++) {
asd = notifier->subdevs[i];
switch (asd->match_type) {
case V4L2_ASYNC_MATCH_CUSTOM:
case V4L2_ASYNC_MATCH_DEVNAME:
case V4L2_ASYNC_MATCH_I2C:
case V4L2_ASYNC_MATCH_FWNODE:
break;
default:
dev_err(notifier->v4l2_dev ? notifier->v4l2_dev->dev : NULL,
"Invalid match type %u on %p\n",
asd->match_type, asd);
return -EINVAL;
}
list_add_tail(&asd->list, &notifier->waiting);
}
mutex_lock(&list_lock);
list_for_each_entry_safe(sd, tmp, &subdev_list, async_list) {
int ret;
asd = v4l2_async_find_match(notifier, sd);
if (!asd)
continue;
ret = v4l2_async_match_notify(notifier, sd, asd);
if (ret < 0) {
mutex_unlock(&list_lock);
return ret;
}
}
if (list_empty(&notifier->waiting)) {
ret = v4l2_async_notifier_call_complete(notifier);
if (ret)
goto err_complete;
}
/* Keep also completed notifiers on the list */
list_add(&notifier->list, &notifier_list);
mutex_unlock(&list_lock);
return 0;
err_complete:
v4l2_async_notifier_unbind_all_subdevs(notifier);
mutex_unlock(&list_lock);
return ret;
}
EXPORT_SYMBOL(v4l2_async_notifier_register);
void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier)
{
if (!notifier->v4l2_dev)
return;
mutex_lock(&list_lock);
list_del(&notifier->list);
v4l2_async_notifier_unbind_all_subdevs(notifier);
mutex_unlock(&list_lock);
notifier->v4l2_dev = NULL;
}
EXPORT_SYMBOL(v4l2_async_notifier_unregister);
void v4l2_async_notifier_cleanup(struct v4l2_async_notifier *notifier)
{
unsigned int i;
if (!notifier->max_subdevs)
return;
for (i = 0; i < notifier->num_subdevs; i++) {
struct v4l2_async_subdev *asd = notifier->subdevs[i];
switch (asd->match_type) {
case V4L2_ASYNC_MATCH_FWNODE:
fwnode_handle_put(asd->match.fwnode.fwnode);
break;
default:
WARN_ON_ONCE(true);
break;
}
kfree(asd);
}
notifier->max_subdevs = 0;
notifier->num_subdevs = 0;
kvfree(notifier->subdevs);
notifier->subdevs = NULL;
}
EXPORT_SYMBOL_GPL(v4l2_async_notifier_cleanup);
int v4l2_async_register_subdev(struct v4l2_subdev *sd)
{
struct v4l2_async_notifier *notifier;
int ret;
/*
* No reference taken. The reference is held by the device
* (struct v4l2_subdev.dev), and async sub-device does not
* exist independently of the device at any point of time.
*/
if (!sd->fwnode && sd->dev)
sd->fwnode = dev_fwnode(sd->dev);
mutex_lock(&list_lock);
INIT_LIST_HEAD(&sd->async_list);
list_for_each_entry(notifier, &notifier_list, list) {
struct v4l2_async_subdev *asd = v4l2_async_find_match(notifier,
sd);
int ret;
if (!asd)
continue;
ret = v4l2_async_match_notify(notifier, sd, asd);
if (ret)
goto err_unlock;
if (!list_empty(&notifier->waiting))
goto out_unlock;
ret = v4l2_async_notifier_call_complete(notifier);
if (ret)
goto err_cleanup;
goto out_unlock;
}
/* None matched, wait for hot-plugging */
list_add(&sd->async_list, &subdev_list);
out_unlock:
mutex_unlock(&list_lock);
return 0;
err_cleanup:
v4l2_async_notifier_call_unbind(notifier, sd, sd->asd);
v4l2_async_cleanup(sd);
err_unlock:
mutex_unlock(&list_lock);
return ret;
}
EXPORT_SYMBOL(v4l2_async_register_subdev);
void v4l2_async_unregister_subdev(struct v4l2_subdev *sd)
{
mutex_lock(&list_lock);
if (sd->asd) {
struct v4l2_async_notifier *notifier = sd->notifier;
list_add(&sd->asd->list, &notifier->waiting);
v4l2_async_notifier_call_unbind(notifier, sd, sd->asd);
}
v4l2_async_cleanup(sd);
mutex_unlock(&list_lock);
}
EXPORT_SYMBOL(v4l2_async_unregister_subdev);