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-rw-r--r--extras/recipes-kernel/linux/linux-omap/media/0008-media-Media-device-node-support.patch500
1 files changed, 500 insertions, 0 deletions
diff --git a/extras/recipes-kernel/linux/linux-omap/media/0008-media-Media-device-node-support.patch b/extras/recipes-kernel/linux/linux-omap/media/0008-media-Media-device-node-support.patch
new file mode 100644
index 00000000..fd8b4952
--- /dev/null
+++ b/extras/recipes-kernel/linux/linux-omap/media/0008-media-Media-device-node-support.patch
@@ -0,0 +1,500 @@
1From 27c789f3ae1d24212355d10857efb2d406d0fedd Mon Sep 17 00:00:00 2001
2From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
3Date: Wed, 9 Dec 2009 12:39:56 +0100
4Subject: [PATCH 08/43] media: Media device node support
5
6The media_devnode structure provides support for registering and
7unregistering character devices using a dynamic major number. Reference
8counting is handled internally, making device drivers easier to write
9without having to solve the open/disconnect race condition issue over
10and over again.
11
12The code is based on video/v4l2-dev.c.
13
14Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
15---
16 drivers/media/Kconfig | 13 ++
17 drivers/media/Makefile | 10 +-
18 drivers/media/media-devnode.c | 321 +++++++++++++++++++++++++++++++++++++++++
19 include/media/media-devnode.h | 97 +++++++++++++
20 4 files changed, 439 insertions(+), 2 deletions(-)
21 create mode 100644 drivers/media/media-devnode.c
22 create mode 100644 include/media/media-devnode.h
23
24diff --git a/drivers/media/Kconfig b/drivers/media/Kconfig
25index a28541b..6b946e6 100644
26--- a/drivers/media/Kconfig
27+++ b/drivers/media/Kconfig
28@@ -14,6 +14,19 @@ if MEDIA_SUPPORT
29 comment "Multimedia core support"
30
31 #
32+# Media controller
33+#
34+
35+config MEDIA_CONTROLLER
36+ bool "Media Controller API (EXPERIMENTAL)"
37+ depends on EXPERIMENTAL
38+ ---help---
39+ Enable the media controller API used to query media devices internal
40+ topology and configure it dynamically.
41+
42+ This API is mostly used by camera interfaces in embedded platforms.
43+
44+#
45 # V4L core and enabled API's
46 #
47
48diff --git a/drivers/media/Makefile b/drivers/media/Makefile
49index 499b081..3a08991 100644
50--- a/drivers/media/Makefile
51+++ b/drivers/media/Makefile
52@@ -2,7 +2,13 @@
53 # Makefile for the kernel multimedia device drivers.
54 #
55
56+media-objs := media-devnode.o
57+
58+ifeq ($(CONFIG_MEDIA_CONTROLLER),y)
59+ obj-$(CONFIG_MEDIA_SUPPORT) += media.o
60+endif
61+
62 obj-y += common/ IR/ video/
63
64-obj-$(CONFIG_VIDEO_DEV) += radio/
65-obj-$(CONFIG_DVB_CORE) += dvb/
66+obj-$(CONFIG_VIDEO_DEV) += radio/
67+obj-$(CONFIG_DVB_CORE) += dvb/
68diff --git a/drivers/media/media-devnode.c b/drivers/media/media-devnode.c
69new file mode 100644
70index 0000000..7804b70
71--- /dev/null
72+++ b/drivers/media/media-devnode.c
73@@ -0,0 +1,321 @@
74+/*
75+ * Media device node
76+ *
77+ * Copyright (C) 2010 Nokia Corporation
78+ *
79+ * Based on drivers/media/video/v4l2_dev.c code authored by
80+ * Mauro Carvalho Chehab <mchehab@infradead.org> (version 2)
81+ * Alan Cox, <alan@lxorguk.ukuu.org.uk> (version 1)
82+ *
83+ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
84+ * Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
85+ *
86+ * This program is free software; you can redistribute it and/or modify
87+ * it under the terms of the GNU General Public License version 2 as
88+ * published by the Free Software Foundation.
89+ *
90+ * This program is distributed in the hope that it will be useful,
91+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
92+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
93+ * GNU General Public License for more details.
94+ *
95+ * You should have received a copy of the GNU General Public License
96+ * along with this program; if not, write to the Free Software
97+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
98+ *
99+ * --
100+ *
101+ * Generic media device node infrastructure to register and unregister
102+ * character devices using a dynamic major number and proper reference
103+ * counting.
104+ */
105+
106+#include <linux/errno.h>
107+#include <linux/init.h>
108+#include <linux/module.h>
109+#include <linux/kernel.h>
110+#include <linux/kmod.h>
111+#include <linux/slab.h>
112+#include <linux/mm.h>
113+#include <linux/smp_lock.h>
114+#include <linux/string.h>
115+#include <linux/types.h>
116+#include <linux/uaccess.h>
117+#include <asm/system.h>
118+
119+#include <media/media-devnode.h>
120+
121+#define MEDIA_NUM_DEVICES 256
122+#define MEDIA_NAME "media"
123+
124+static dev_t media_dev_t;
125+
126+/*
127+ * Active devices
128+ */
129+static DEFINE_MUTEX(media_devnode_lock);
130+static DECLARE_BITMAP(media_devnode_nums, MEDIA_NUM_DEVICES);
131+
132+/* Called when the last user of the media device exits. */
133+static void media_devnode_release(struct device *cd)
134+{
135+ struct media_devnode *mdev = to_media_devnode(cd);
136+
137+ mutex_lock(&media_devnode_lock);
138+
139+ /* Delete the cdev on this minor as well */
140+ cdev_del(&mdev->cdev);
141+
142+ /* Mark device node number as free */
143+ clear_bit(mdev->minor, media_devnode_nums);
144+
145+ mutex_unlock(&media_devnode_lock);
146+
147+ /* Release media_devnode and perform other cleanups as needed. */
148+ if (mdev->release)
149+ mdev->release(mdev);
150+}
151+
152+static struct bus_type media_bus_type = {
153+ .name = MEDIA_NAME,
154+};
155+
156+static ssize_t media_read(struct file *filp, char __user *buf,
157+ size_t sz, loff_t *off)
158+{
159+ struct media_devnode *mdev = media_devnode_data(filp);
160+
161+ if (!mdev->fops->read)
162+ return -EINVAL;
163+ if (!media_devnode_is_registered(mdev))
164+ return -EIO;
165+ return mdev->fops->read(filp, buf, sz, off);
166+}
167+
168+static ssize_t media_write(struct file *filp, const char __user *buf,
169+ size_t sz, loff_t *off)
170+{
171+ struct media_devnode *mdev = media_devnode_data(filp);
172+
173+ if (!mdev->fops->write)
174+ return -EINVAL;
175+ if (!media_devnode_is_registered(mdev))
176+ return -EIO;
177+ return mdev->fops->write(filp, buf, sz, off);
178+}
179+
180+static unsigned int media_poll(struct file *filp,
181+ struct poll_table_struct *poll)
182+{
183+ struct media_devnode *mdev = media_devnode_data(filp);
184+
185+ if (!media_devnode_is_registered(mdev))
186+ return POLLERR | POLLHUP;
187+ if (!mdev->fops->poll)
188+ return DEFAULT_POLLMASK;
189+ return mdev->fops->poll(filp, poll);
190+}
191+
192+static long media_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
193+{
194+ struct media_devnode *mdev = media_devnode_data(filp);
195+
196+ if (!mdev->fops->ioctl)
197+ return -ENOTTY;
198+
199+ if (!media_devnode_is_registered(mdev))
200+ return -EIO;
201+
202+ return mdev->fops->ioctl(filp, cmd, arg);
203+}
204+
205+/* Override for the open function */
206+static int media_open(struct inode *inode, struct file *filp)
207+{
208+ struct media_devnode *mdev;
209+ int ret;
210+
211+ /* Check if the media device is available. This needs to be done with
212+ * the media_devnode_lock held to prevent an open/unregister race:
213+ * without the lock, the device could be unregistered and freed between
214+ * the media_devnode_is_registered() and get_device() calls, leading to
215+ * a crash.
216+ */
217+ mutex_lock(&media_devnode_lock);
218+ mdev = container_of(inode->i_cdev, struct media_devnode, cdev);
219+ /* return ENXIO if the media device has been removed
220+ already or if it is not registered anymore. */
221+ if (!media_devnode_is_registered(mdev)) {
222+ mutex_unlock(&media_devnode_lock);
223+ return -ENXIO;
224+ }
225+ /* and increase the device refcount */
226+ get_device(&mdev->dev);
227+ mutex_unlock(&media_devnode_lock);
228+
229+ filp->private_data = mdev;
230+
231+ if (mdev->fops->open) {
232+ ret = mdev->fops->open(filp);
233+ if (ret) {
234+ put_device(&mdev->dev);
235+ return ret;
236+ }
237+ }
238+
239+ return 0;
240+}
241+
242+/* Override for the release function */
243+static int media_release(struct inode *inode, struct file *filp)
244+{
245+ struct media_devnode *mdev = media_devnode_data(filp);
246+ int ret = 0;
247+
248+ if (mdev->fops->release)
249+ mdev->fops->release(filp);
250+
251+ /* decrease the refcount unconditionally since the release()
252+ return value is ignored. */
253+ put_device(&mdev->dev);
254+ filp->private_data = NULL;
255+ return ret;
256+}
257+
258+static const struct file_operations media_devnode_fops = {
259+ .owner = THIS_MODULE,
260+ .read = media_read,
261+ .write = media_write,
262+ .open = media_open,
263+ .unlocked_ioctl = media_ioctl,
264+ .release = media_release,
265+ .poll = media_poll,
266+ .llseek = no_llseek,
267+};
268+
269+/**
270+ * media_devnode_register - register a media device node
271+ * @mdev: media device node structure we want to register
272+ *
273+ * The registration code assigns minor numbers and registers the new device node
274+ * with the kernel. An error is returned if no free minor number can be found,
275+ * or if the registration of the device node fails.
276+ *
277+ * Zero is returned on success.
278+ *
279+ * Note that if the media_devnode_register call fails, the release() callback of
280+ * the media_devnode structure is *not* called, so the caller is responsible for
281+ * freeing any data.
282+ */
283+int __must_check media_devnode_register(struct media_devnode *mdev)
284+{
285+ int minor;
286+ int ret;
287+
288+ /* Part 1: Find a free minor number */
289+ mutex_lock(&media_devnode_lock);
290+ minor = find_next_zero_bit(media_devnode_nums, 0, MEDIA_NUM_DEVICES);
291+ if (minor == MEDIA_NUM_DEVICES) {
292+ mutex_unlock(&media_devnode_lock);
293+ printk(KERN_ERR "could not get a free minor\n");
294+ return -ENFILE;
295+ }
296+
297+ set_bit(mdev->minor, media_devnode_nums);
298+ mutex_unlock(&media_devnode_lock);
299+
300+ mdev->minor = minor;
301+
302+ /* Part 2: Initialize and register the character device */
303+ cdev_init(&mdev->cdev, &media_devnode_fops);
304+ mdev->cdev.owner = mdev->fops->owner;
305+
306+ ret = cdev_add(&mdev->cdev, MKDEV(MAJOR(media_dev_t), mdev->minor), 1);
307+ if (ret < 0) {
308+ printk(KERN_ERR "%s: cdev_add failed\n", __func__);
309+ goto error;
310+ }
311+
312+ /* Part 3: Register the media device */
313+ mdev->dev.bus = &media_bus_type;
314+ mdev->dev.devt = MKDEV(MAJOR(media_dev_t), mdev->minor);
315+ mdev->dev.release = media_devnode_release;
316+ if (mdev->parent)
317+ mdev->dev.parent = mdev->parent;
318+ dev_set_name(&mdev->dev, "media%d", mdev->minor);
319+ ret = device_register(&mdev->dev);
320+ if (ret < 0) {
321+ printk(KERN_ERR "%s: device_register failed\n", __func__);
322+ goto error;
323+ }
324+
325+ /* Part 4: Activate this minor. The char device can now be used. */
326+ set_bit(MEDIA_FLAG_REGISTERED, &mdev->flags);
327+
328+ return 0;
329+
330+error:
331+ cdev_del(&mdev->cdev);
332+ clear_bit(mdev->minor, media_devnode_nums);
333+ return ret;
334+}
335+
336+/**
337+ * media_devnode_unregister - unregister a media device node
338+ * @mdev: the device node to unregister
339+ *
340+ * This unregisters the passed device. Future open calls will be met with
341+ * errors.
342+ *
343+ * This function can safely be called if the device node has never been
344+ * registered or has already been unregistered.
345+ */
346+void media_devnode_unregister(struct media_devnode *mdev)
347+{
348+ /* Check if mdev was ever registered at all */
349+ if (!media_devnode_is_registered(mdev))
350+ return;
351+
352+ mutex_lock(&media_devnode_lock);
353+ clear_bit(MEDIA_FLAG_REGISTERED, &mdev->flags);
354+ mutex_unlock(&media_devnode_lock);
355+ device_unregister(&mdev->dev);
356+}
357+
358+/*
359+ * Initialise media for linux
360+ */
361+static int __init media_devnode_init(void)
362+{
363+ int ret;
364+
365+ printk(KERN_INFO "Linux media interface: v0.10\n");
366+ ret = alloc_chrdev_region(&media_dev_t, 0, MEDIA_NUM_DEVICES,
367+ MEDIA_NAME);
368+ if (ret < 0) {
369+ printk(KERN_WARNING "media: unable to allocate major\n");
370+ return ret;
371+ }
372+
373+ ret = bus_register(&media_bus_type);
374+ if (ret < 0) {
375+ unregister_chrdev_region(media_dev_t, MEDIA_NUM_DEVICES);
376+ printk(KERN_WARNING "media: bus_register failed\n");
377+ return -EIO;
378+ }
379+
380+ return 0;
381+}
382+
383+static void __exit media_devnode_exit(void)
384+{
385+ bus_unregister(&media_bus_type);
386+ unregister_chrdev_region(media_dev_t, MEDIA_NUM_DEVICES);
387+}
388+
389+module_init(media_devnode_init)
390+module_exit(media_devnode_exit)
391+
392+MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
393+MODULE_DESCRIPTION("Device node registration for media drivers");
394+MODULE_LICENSE("GPL");
395diff --git a/include/media/media-devnode.h b/include/media/media-devnode.h
396new file mode 100644
397index 0000000..01cd034
398--- /dev/null
399+++ b/include/media/media-devnode.h
400@@ -0,0 +1,97 @@
401+/*
402+ * Media device node
403+ *
404+ * Copyright (C) 2010 Nokia Corporation
405+ *
406+ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
407+ * Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
408+ *
409+ * This program is free software; you can redistribute it and/or modify
410+ * it under the terms of the GNU General Public License version 2 as
411+ * published by the Free Software Foundation.
412+ *
413+ * This program is distributed in the hope that it will be useful,
414+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
415+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
416+ * GNU General Public License for more details.
417+ *
418+ * You should have received a copy of the GNU General Public License
419+ * along with this program; if not, write to the Free Software
420+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
421+ *
422+ * --
423+ *
424+ * Common functions for media-related drivers to register and unregister media
425+ * device nodes.
426+ */
427+
428+#ifndef _MEDIA_DEVNODE_H
429+#define _MEDIA_DEVNODE_H
430+
431+#include <linux/poll.h>
432+#include <linux/fs.h>
433+#include <linux/device.h>
434+#include <linux/cdev.h>
435+
436+/*
437+ * Flag to mark the media_devnode struct as registered. Drivers must not touch
438+ * this flag directly, it will be set and cleared by media_devnode_register and
439+ * media_devnode_unregister.
440+ */
441+#define MEDIA_FLAG_REGISTERED 0
442+
443+struct media_file_operations {
444+ struct module *owner;
445+ ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
446+ ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
447+ unsigned int (*poll) (struct file *, struct poll_table_struct *);
448+ long (*ioctl) (struct file *, unsigned int, unsigned long);
449+ int (*open) (struct file *);
450+ int (*release) (struct file *);
451+};
452+
453+/**
454+ * struct media_devnode - Media device node
455+ * @parent: parent device
456+ * @minor: device node minor number
457+ * @flags: flags, combination of the MEDIA_FLAG_* constants
458+ *
459+ * This structure represents a media-related device node.
460+ *
461+ * The @parent is a physical device. It must be set by core or device drivers
462+ * before registering the node.
463+ */
464+struct media_devnode {
465+ /* device ops */
466+ const struct media_file_operations *fops;
467+
468+ /* sysfs */
469+ struct device dev; /* media device */
470+ struct cdev cdev; /* character device */
471+ struct device *parent; /* device parent */
472+
473+ /* device info */
474+ int minor;
475+ unsigned long flags; /* Use bitops to access flags */
476+
477+ /* callbacks */
478+ void (*release)(struct media_devnode *mdev);
479+};
480+
481+/* dev to media_devnode */
482+#define to_media_devnode(cd) container_of(cd, struct media_devnode, dev)
483+
484+int __must_check media_devnode_register(struct media_devnode *mdev);
485+void media_devnode_unregister(struct media_devnode *mdev);
486+
487+static inline struct media_devnode *media_devnode_data(struct file *filp)
488+{
489+ return filp->private_data;
490+}
491+
492+static inline int media_devnode_is_registered(struct media_devnode *mdev)
493+{
494+ return test_bit(MEDIA_FLAG_REGISTERED, &mdev->flags);
495+}
496+
497+#endif /* _MEDIA_DEVNODE_H */
498--
4991.6.6.1
500
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