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-rw-r--r--recipes/linux/linux-omap-2.6.37/media/0008-media-Media-device-node-support.patch500
1 files changed, 500 insertions, 0 deletions
diff --git a/recipes/linux/linux-omap-2.6.37/media/0008-media-Media-device-node-support.patch b/recipes/linux/linux-omap-2.6.37/media/0008-media-Media-device-node-support.patch
new file mode 100644
index 0000000000..fd8b4952d6
--- /dev/null
+++ b/recipes/linux/linux-omap-2.6.37/media/0008-media-Media-device-node-support.patch
@@ -0,0 +1,500 @@
+From 27c789f3ae1d24212355d10857efb2d406d0fedd Mon Sep 17 00:00:00 2001
+From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+Date: Wed, 9 Dec 2009 12:39:56 +0100
+Subject: [PATCH 08/43] media: Media device node support
+
+The media_devnode structure provides support for registering and
+unregistering character devices using a dynamic major number. Reference
+counting is handled internally, making device drivers easier to write
+without having to solve the open/disconnect race condition issue over
+and over again.
+
+The code is based on video/v4l2-dev.c.
+
+Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+---
+ drivers/media/Kconfig | 13 ++
+ drivers/media/Makefile | 10 +-
+ drivers/media/media-devnode.c | 321 +++++++++++++++++++++++++++++++++++++++++
+ include/media/media-devnode.h | 97 +++++++++++++
+ 4 files changed, 439 insertions(+), 2 deletions(-)
+ create mode 100644 drivers/media/media-devnode.c
+ create mode 100644 include/media/media-devnode.h
+
+diff --git a/drivers/media/Kconfig b/drivers/media/Kconfig
+index a28541b..6b946e6 100644
+--- a/drivers/media/Kconfig
++++ b/drivers/media/Kconfig
+@@ -14,6 +14,19 @@ if MEDIA_SUPPORT
+ comment "Multimedia core support"
+
+ #
++# Media controller
++#
++
++config MEDIA_CONTROLLER
++ bool "Media Controller API (EXPERIMENTAL)"
++ depends on EXPERIMENTAL
++ ---help---
++ Enable the media controller API used to query media devices internal
++ topology and configure it dynamically.
++
++ This API is mostly used by camera interfaces in embedded platforms.
++
++#
+ # V4L core and enabled API's
+ #
+
+diff --git a/drivers/media/Makefile b/drivers/media/Makefile
+index 499b081..3a08991 100644
+--- a/drivers/media/Makefile
++++ b/drivers/media/Makefile
+@@ -2,7 +2,13 @@
+ # Makefile for the kernel multimedia device drivers.
+ #
+
++media-objs := media-devnode.o
++
++ifeq ($(CONFIG_MEDIA_CONTROLLER),y)
++ obj-$(CONFIG_MEDIA_SUPPORT) += media.o
++endif
++
+ obj-y += common/ IR/ video/
+
+-obj-$(CONFIG_VIDEO_DEV) += radio/
+-obj-$(CONFIG_DVB_CORE) += dvb/
++obj-$(CONFIG_VIDEO_DEV) += radio/
++obj-$(CONFIG_DVB_CORE) += dvb/
+diff --git a/drivers/media/media-devnode.c b/drivers/media/media-devnode.c
+new file mode 100644
+index 0000000..7804b70
+--- /dev/null
++++ b/drivers/media/media-devnode.c
+@@ -0,0 +1,321 @@
++/*
++ * Media device node
++ *
++ * Copyright (C) 2010 Nokia Corporation
++ *
++ * Based on drivers/media/video/v4l2_dev.c code authored by
++ * Mauro Carvalho Chehab <mchehab@infradead.org> (version 2)
++ * Alan Cox, <alan@lxorguk.ukuu.org.uk> (version 1)
++ *
++ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
++ * Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
++ *
++ * 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.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public License
++ * along with this program; if not, write to the Free Software
++ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
++ *
++ * --
++ *
++ * Generic media device node infrastructure to register and unregister
++ * character devices using a dynamic major number and proper reference
++ * counting.
++ */
++
++#include <linux/errno.h>
++#include <linux/init.h>
++#include <linux/module.h>
++#include <linux/kernel.h>
++#include <linux/kmod.h>
++#include <linux/slab.h>
++#include <linux/mm.h>
++#include <linux/smp_lock.h>
++#include <linux/string.h>
++#include <linux/types.h>
++#include <linux/uaccess.h>
++#include <asm/system.h>
++
++#include <media/media-devnode.h>
++
++#define MEDIA_NUM_DEVICES 256
++#define MEDIA_NAME "media"
++
++static dev_t media_dev_t;
++
++/*
++ * Active devices
++ */
++static DEFINE_MUTEX(media_devnode_lock);
++static DECLARE_BITMAP(media_devnode_nums, MEDIA_NUM_DEVICES);
++
++/* Called when the last user of the media device exits. */
++static void media_devnode_release(struct device *cd)
++{
++ struct media_devnode *mdev = to_media_devnode(cd);
++
++ mutex_lock(&media_devnode_lock);
++
++ /* Delete the cdev on this minor as well */
++ cdev_del(&mdev->cdev);
++
++ /* Mark device node number as free */
++ clear_bit(mdev->minor, media_devnode_nums);
++
++ mutex_unlock(&media_devnode_lock);
++
++ /* Release media_devnode and perform other cleanups as needed. */
++ if (mdev->release)
++ mdev->release(mdev);
++}
++
++static struct bus_type media_bus_type = {
++ .name = MEDIA_NAME,
++};
++
++static ssize_t media_read(struct file *filp, char __user *buf,
++ size_t sz, loff_t *off)
++{
++ struct media_devnode *mdev = media_devnode_data(filp);
++
++ if (!mdev->fops->read)
++ return -EINVAL;
++ if (!media_devnode_is_registered(mdev))
++ return -EIO;
++ return mdev->fops->read(filp, buf, sz, off);
++}
++
++static ssize_t media_write(struct file *filp, const char __user *buf,
++ size_t sz, loff_t *off)
++{
++ struct media_devnode *mdev = media_devnode_data(filp);
++
++ if (!mdev->fops->write)
++ return -EINVAL;
++ if (!media_devnode_is_registered(mdev))
++ return -EIO;
++ return mdev->fops->write(filp, buf, sz, off);
++}
++
++static unsigned int media_poll(struct file *filp,
++ struct poll_table_struct *poll)
++{
++ struct media_devnode *mdev = media_devnode_data(filp);
++
++ if (!media_devnode_is_registered(mdev))
++ return POLLERR | POLLHUP;
++ if (!mdev->fops->poll)
++ return DEFAULT_POLLMASK;
++ return mdev->fops->poll(filp, poll);
++}
++
++static long media_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
++{
++ struct media_devnode *mdev = media_devnode_data(filp);
++
++ if (!mdev->fops->ioctl)
++ return -ENOTTY;
++
++ if (!media_devnode_is_registered(mdev))
++ return -EIO;
++
++ return mdev->fops->ioctl(filp, cmd, arg);
++}
++
++/* Override for the open function */
++static int media_open(struct inode *inode, struct file *filp)
++{
++ struct media_devnode *mdev;
++ int ret;
++
++ /* Check if the media device is available. This needs to be done with
++ * the media_devnode_lock held to prevent an open/unregister race:
++ * without the lock, the device could be unregistered and freed between
++ * the media_devnode_is_registered() and get_device() calls, leading to
++ * a crash.
++ */
++ mutex_lock(&media_devnode_lock);
++ mdev = container_of(inode->i_cdev, struct media_devnode, cdev);
++ /* return ENXIO if the media device has been removed
++ already or if it is not registered anymore. */
++ if (!media_devnode_is_registered(mdev)) {
++ mutex_unlock(&media_devnode_lock);
++ return -ENXIO;
++ }
++ /* and increase the device refcount */
++ get_device(&mdev->dev);
++ mutex_unlock(&media_devnode_lock);
++
++ filp->private_data = mdev;
++
++ if (mdev->fops->open) {
++ ret = mdev->fops->open(filp);
++ if (ret) {
++ put_device(&mdev->dev);
++ return ret;
++ }
++ }
++
++ return 0;
++}
++
++/* Override for the release function */
++static int media_release(struct inode *inode, struct file *filp)
++{
++ struct media_devnode *mdev = media_devnode_data(filp);
++ int ret = 0;
++
++ if (mdev->fops->release)
++ mdev->fops->release(filp);
++
++ /* decrease the refcount unconditionally since the release()
++ return value is ignored. */
++ put_device(&mdev->dev);
++ filp->private_data = NULL;
++ return ret;
++}
++
++static const struct file_operations media_devnode_fops = {
++ .owner = THIS_MODULE,
++ .read = media_read,
++ .write = media_write,
++ .open = media_open,
++ .unlocked_ioctl = media_ioctl,
++ .release = media_release,
++ .poll = media_poll,
++ .llseek = no_llseek,
++};
++
++/**
++ * media_devnode_register - register a media device node
++ * @mdev: media device node structure we want to register
++ *
++ * The registration code assigns minor numbers and registers the new device node
++ * with the kernel. An error is returned if no free minor number can be found,
++ * or if the registration of the device node fails.
++ *
++ * Zero is returned on success.
++ *
++ * Note that if the media_devnode_register call fails, the release() callback of
++ * the media_devnode structure is *not* called, so the caller is responsible for
++ * freeing any data.
++ */
++int __must_check media_devnode_register(struct media_devnode *mdev)
++{
++ int minor;
++ int ret;
++
++ /* Part 1: Find a free minor number */
++ mutex_lock(&media_devnode_lock);
++ minor = find_next_zero_bit(media_devnode_nums, 0, MEDIA_NUM_DEVICES);
++ if (minor == MEDIA_NUM_DEVICES) {
++ mutex_unlock(&media_devnode_lock);
++ printk(KERN_ERR "could not get a free minor\n");
++ return -ENFILE;
++ }
++
++ set_bit(mdev->minor, media_devnode_nums);
++ mutex_unlock(&media_devnode_lock);
++
++ mdev->minor = minor;
++
++ /* Part 2: Initialize and register the character device */
++ cdev_init(&mdev->cdev, &media_devnode_fops);
++ mdev->cdev.owner = mdev->fops->owner;
++
++ ret = cdev_add(&mdev->cdev, MKDEV(MAJOR(media_dev_t), mdev->minor), 1);
++ if (ret < 0) {
++ printk(KERN_ERR "%s: cdev_add failed\n", __func__);
++ goto error;
++ }
++
++ /* Part 3: Register the media device */
++ mdev->dev.bus = &media_bus_type;
++ mdev->dev.devt = MKDEV(MAJOR(media_dev_t), mdev->minor);
++ mdev->dev.release = media_devnode_release;
++ if (mdev->parent)
++ mdev->dev.parent = mdev->parent;
++ dev_set_name(&mdev->dev, "media%d", mdev->minor);
++ ret = device_register(&mdev->dev);
++ if (ret < 0) {
++ printk(KERN_ERR "%s: device_register failed\n", __func__);
++ goto error;
++ }
++
++ /* Part 4: Activate this minor. The char device can now be used. */
++ set_bit(MEDIA_FLAG_REGISTERED, &mdev->flags);
++
++ return 0;
++
++error:
++ cdev_del(&mdev->cdev);
++ clear_bit(mdev->minor, media_devnode_nums);
++ return ret;
++}
++
++/**
++ * media_devnode_unregister - unregister a media device node
++ * @mdev: the device node to unregister
++ *
++ * This unregisters the passed device. Future open calls will be met with
++ * errors.
++ *
++ * This function can safely be called if the device node has never been
++ * registered or has already been unregistered.
++ */
++void media_devnode_unregister(struct media_devnode *mdev)
++{
++ /* Check if mdev was ever registered at all */
++ if (!media_devnode_is_registered(mdev))
++ return;
++
++ mutex_lock(&media_devnode_lock);
++ clear_bit(MEDIA_FLAG_REGISTERED, &mdev->flags);
++ mutex_unlock(&media_devnode_lock);
++ device_unregister(&mdev->dev);
++}
++
++/*
++ * Initialise media for linux
++ */
++static int __init media_devnode_init(void)
++{
++ int ret;
++
++ printk(KERN_INFO "Linux media interface: v0.10\n");
++ ret = alloc_chrdev_region(&media_dev_t, 0, MEDIA_NUM_DEVICES,
++ MEDIA_NAME);
++ if (ret < 0) {
++ printk(KERN_WARNING "media: unable to allocate major\n");
++ return ret;
++ }
++
++ ret = bus_register(&media_bus_type);
++ if (ret < 0) {
++ unregister_chrdev_region(media_dev_t, MEDIA_NUM_DEVICES);
++ printk(KERN_WARNING "media: bus_register failed\n");
++ return -EIO;
++ }
++
++ return 0;
++}
++
++static void __exit media_devnode_exit(void)
++{
++ bus_unregister(&media_bus_type);
++ unregister_chrdev_region(media_dev_t, MEDIA_NUM_DEVICES);
++}
++
++module_init(media_devnode_init)
++module_exit(media_devnode_exit)
++
++MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
++MODULE_DESCRIPTION("Device node registration for media drivers");
++MODULE_LICENSE("GPL");
+diff --git a/include/media/media-devnode.h b/include/media/media-devnode.h
+new file mode 100644
+index 0000000..01cd034
+--- /dev/null
++++ b/include/media/media-devnode.h
+@@ -0,0 +1,97 @@
++/*
++ * Media device node
++ *
++ * Copyright (C) 2010 Nokia Corporation
++ *
++ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
++ * Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
++ *
++ * 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.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public License
++ * along with this program; if not, write to the Free Software
++ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
++ *
++ * --
++ *
++ * Common functions for media-related drivers to register and unregister media
++ * device nodes.
++ */
++
++#ifndef _MEDIA_DEVNODE_H
++#define _MEDIA_DEVNODE_H
++
++#include <linux/poll.h>
++#include <linux/fs.h>
++#include <linux/device.h>
++#include <linux/cdev.h>
++
++/*
++ * Flag to mark the media_devnode struct as registered. Drivers must not touch
++ * this flag directly, it will be set and cleared by media_devnode_register and
++ * media_devnode_unregister.
++ */
++#define MEDIA_FLAG_REGISTERED 0
++
++struct media_file_operations {
++ struct module *owner;
++ ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
++ ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
++ unsigned int (*poll) (struct file *, struct poll_table_struct *);
++ long (*ioctl) (struct file *, unsigned int, unsigned long);
++ int (*open) (struct file *);
++ int (*release) (struct file *);
++};
++
++/**
++ * struct media_devnode - Media device node
++ * @parent: parent device
++ * @minor: device node minor number
++ * @flags: flags, combination of the MEDIA_FLAG_* constants
++ *
++ * This structure represents a media-related device node.
++ *
++ * The @parent is a physical device. It must be set by core or device drivers
++ * before registering the node.
++ */
++struct media_devnode {
++ /* device ops */
++ const struct media_file_operations *fops;
++
++ /* sysfs */
++ struct device dev; /* media device */
++ struct cdev cdev; /* character device */
++ struct device *parent; /* device parent */
++
++ /* device info */
++ int minor;
++ unsigned long flags; /* Use bitops to access flags */
++
++ /* callbacks */
++ void (*release)(struct media_devnode *mdev);
++};
++
++/* dev to media_devnode */
++#define to_media_devnode(cd) container_of(cd, struct media_devnode, dev)
++
++int __must_check media_devnode_register(struct media_devnode *mdev);
++void media_devnode_unregister(struct media_devnode *mdev);
++
++static inline struct media_devnode *media_devnode_data(struct file *filp)
++{
++ return filp->private_data;
++}
++
++static inline int media_devnode_is_registered(struct media_devnode *mdev)
++{
++ return test_bit(MEDIA_FLAG_REGISTERED, &mdev->flags);
++}
++
++#endif /* _MEDIA_DEVNODE_H */
+--
+1.6.6.1
+
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