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path: root/drivers/media/video/videocodec.c
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Diffstat (limited to 'drivers/media/video/videocodec.c')
-rw-r--r--drivers/media/video/videocodec.c490
1 files changed, 490 insertions, 0 deletions
diff --git a/drivers/media/video/videocodec.c b/drivers/media/video/videocodec.c
new file mode 100644
index 00000000000..c9d5f1a873c
--- /dev/null
+++ b/drivers/media/video/videocodec.c
@@ -0,0 +1,490 @@
+/*
+ * VIDEO MOTION CODECs internal API for video devices
+ *
+ * Interface for MJPEG (and maybe later MPEG/WAVELETS) codec's
+ * bound to a master device.
+ *
+ * (c) 2002 Wolfgang Scherr <scherr@net4you.at>
+ *
+ * $Id: videocodec.c,v 1.1.2.8 2003/03/29 07:16:04 rbultje Exp $
+ *
+ * ------------------------------------------------------------------------
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * ------------------------------------------------------------------------
+ */
+
+#define VIDEOCODEC_VERSION "v0.2"
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+
+// kernel config is here (procfs flag)
+#include <linux/config.h>
+
+#ifdef CONFIG_PROC_FS
+#include <linux/proc_fs.h>
+#include <asm/uaccess.h>
+#endif
+
+#include "videocodec.h"
+
+static int debug = 0;
+module_param(debug, int, 0);
+MODULE_PARM_DESC(debug, "Debug level (0-4)");
+
+#define dprintk(num, format, args...) \
+ do { \
+ if (debug >= num) \
+ printk(format, ##args); \
+ } while (0)
+
+struct attached_list {
+ struct videocodec *codec;
+ struct attached_list *next;
+};
+
+struct codec_list {
+ const struct videocodec *codec;
+ int attached;
+ struct attached_list *list;
+ struct codec_list *next;
+};
+
+static struct codec_list *codeclist_top = NULL;
+
+/* ================================================= */
+/* function prototypes of the master/slave interface */
+/* ================================================= */
+
+struct videocodec *
+videocodec_attach (struct videocodec_master *master)
+{
+ struct codec_list *h = codeclist_top;
+ struct attached_list *a, *ptr;
+ struct videocodec *codec;
+ int res;
+
+ if (!master) {
+ dprintk(1, KERN_ERR "videocodec_attach: no data\n");
+ return NULL;
+ }
+
+ dprintk(2,
+ "videocodec_attach: '%s', type: %x, flags %lx, magic %lx\n",
+ master->name, master->type, master->flags, master->magic);
+
+ if (!h) {
+ dprintk(1,
+ KERN_ERR
+ "videocodec_attach: no device available\n");
+ return NULL;
+ }
+
+ while (h) {
+ // attach only if the slave has at least the flags
+ // expected by the master
+ if ((master->flags & h->codec->flags) == master->flags) {
+ dprintk(4, "videocodec_attach: try '%s'\n",
+ h->codec->name);
+
+ if (!try_module_get(h->codec->owner))
+ return NULL;
+
+ codec =
+ kmalloc(sizeof(struct videocodec), GFP_KERNEL);
+ if (!codec) {
+ dprintk(1,
+ KERN_ERR
+ "videocodec_attach: no mem\n");
+ goto out_module_put;
+ }
+ memcpy(codec, h->codec, sizeof(struct videocodec));
+
+ snprintf(codec->name, sizeof(codec->name),
+ "%s[%d]", codec->name, h->attached);
+ codec->master_data = master;
+ res = codec->setup(codec);
+ if (res == 0) {
+ dprintk(3, "videocodec_attach '%s'\n",
+ codec->name);
+ ptr = (struct attached_list *)
+ kmalloc(sizeof(struct attached_list),
+ GFP_KERNEL);
+ if (!ptr) {
+ dprintk(1,
+ KERN_ERR
+ "videocodec_attach: no memory\n");
+ goto out_kfree;
+ }
+ memset(ptr, 0,
+ sizeof(struct attached_list));
+ ptr->codec = codec;
+
+ a = h->list;
+ if (!a) {
+ h->list = ptr;
+ dprintk(4,
+ "videocodec: first element\n");
+ } else {
+ while (a->next)
+ a = a->next; // find end
+ a->next = ptr;
+ dprintk(4,
+ "videocodec: in after '%s'\n",
+ h->codec->name);
+ }
+
+ h->attached += 1;
+ return codec;
+ } else {
+ kfree(codec);
+ }
+ }
+ h = h->next;
+ }
+
+ dprintk(1, KERN_ERR "videocodec_attach: no codec found!\n");
+ return NULL;
+
+ out_module_put:
+ module_put(h->codec->owner);
+ out_kfree:
+ kfree(codec);
+ return NULL;
+}
+
+int
+videocodec_detach (struct videocodec *codec)
+{
+ struct codec_list *h = codeclist_top;
+ struct attached_list *a, *prev;
+ int res;
+
+ if (!codec) {
+ dprintk(1, KERN_ERR "videocodec_detach: no data\n");
+ return -EINVAL;
+ }
+
+ dprintk(2,
+ "videocodec_detach: '%s', type: %x, flags %lx, magic %lx\n",
+ codec->name, codec->type, codec->flags, codec->magic);
+
+ if (!h) {
+ dprintk(1,
+ KERN_ERR "videocodec_detach: no device left...\n");
+ return -ENXIO;
+ }
+
+ while (h) {
+ a = h->list;
+ prev = NULL;
+ while (a) {
+ if (codec == a->codec) {
+ res = a->codec->unset(a->codec);
+ if (res >= 0) {
+ dprintk(3,
+ "videocodec_detach: '%s'\n",
+ a->codec->name);
+ a->codec->master_data = NULL;
+ } else {
+ dprintk(1,
+ KERN_ERR
+ "videocodec_detach: '%s'\n",
+ a->codec->name);
+ a->codec->master_data = NULL;
+ }
+ if (prev == NULL) {
+ h->list = a->next;
+ dprintk(4,
+ "videocodec: delete first\n");
+ } else {
+ prev->next = a->next;
+ dprintk(4,
+ "videocodec: delete middle\n");
+ }
+ module_put(a->codec->owner);
+ kfree(a->codec);
+ kfree(a);
+ h->attached -= 1;
+ return 0;
+ }
+ prev = a;
+ a = a->next;
+ }
+ h = h->next;
+ }
+
+ dprintk(1, KERN_ERR "videocodec_detach: given codec not found!\n");
+ return -EINVAL;
+}
+
+int
+videocodec_register (const struct videocodec *codec)
+{
+ struct codec_list *ptr, *h = codeclist_top;
+
+ if (!codec) {
+ dprintk(1, KERN_ERR "videocodec_register: no data!\n");
+ return -EINVAL;
+ }
+
+ dprintk(2,
+ "videocodec: register '%s', type: %x, flags %lx, magic %lx\n",
+ codec->name, codec->type, codec->flags, codec->magic);
+
+ ptr =
+ (struct codec_list *) kmalloc(sizeof(struct codec_list),
+ GFP_KERNEL);
+ if (!ptr) {
+ dprintk(1, KERN_ERR "videocodec_register: no memory\n");
+ return -ENOMEM;
+ }
+ memset(ptr, 0, sizeof(struct codec_list));
+ ptr->codec = codec;
+
+ if (!h) {
+ codeclist_top = ptr;
+ dprintk(4, "videocodec: hooked in as first element\n");
+ } else {
+ while (h->next)
+ h = h->next; // find the end
+ h->next = ptr;
+ dprintk(4, "videocodec: hooked in after '%s'\n",
+ h->codec->name);
+ }
+
+ return 0;
+}
+
+int
+videocodec_unregister (const struct videocodec *codec)
+{
+ struct codec_list *prev = NULL, *h = codeclist_top;
+
+ if (!codec) {
+ dprintk(1, KERN_ERR "videocodec_unregister: no data!\n");
+ return -EINVAL;
+ }
+
+ dprintk(2,
+ "videocodec: unregister '%s', type: %x, flags %lx, magic %lx\n",
+ codec->name, codec->type, codec->flags, codec->magic);
+
+ if (!h) {
+ dprintk(1,
+ KERN_ERR
+ "videocodec_unregister: no device left...\n");
+ return -ENXIO;
+ }
+
+ while (h) {
+ if (codec == h->codec) {
+ if (h->attached) {
+ dprintk(1,
+ KERN_ERR
+ "videocodec: '%s' is used\n",
+ h->codec->name);
+ return -EBUSY;
+ }
+ dprintk(3, "videocodec: unregister '%s' is ok.\n",
+ h->codec->name);
+ if (prev == NULL) {
+ codeclist_top = h->next;
+ dprintk(4,
+ "videocodec: delete first element\n");
+ } else {
+ prev->next = h->next;
+ dprintk(4,
+ "videocodec: delete middle element\n");
+ }
+ kfree(h);
+ return 0;
+ }
+ prev = h;
+ h = h->next;
+ }
+
+ dprintk(1,
+ KERN_ERR
+ "videocodec_unregister: given codec not found!\n");
+ return -EINVAL;
+}
+
+#ifdef CONFIG_PROC_FS
+/* ============ */
+/* procfs stuff */
+/* ============ */
+
+static char *videocodec_buf = NULL;
+static int videocodec_bufsize = 0;
+
+static int
+videocodec_build_table (void)
+{
+ struct codec_list *h = codeclist_top;
+ struct attached_list *a;
+ int i = 0, size;
+
+ // sum up amount of slaves plus their attached masters
+ while (h) {
+ i += h->attached + 1;
+ h = h->next;
+ }
+#define LINESIZE 100
+ size = LINESIZE * (i + 1);
+
+ dprintk(3, "videocodec_build table: %d entries, %d bytes\n", i,
+ size);
+
+ if (videocodec_buf)
+ kfree(videocodec_buf);
+ videocodec_buf = (char *) kmalloc(size, GFP_KERNEL);
+
+ i = 0;
+ i += scnprintf(videocodec_buf + i, size - 1,
+ "<S>lave or attached <M>aster name type flags magic ");
+ i += scnprintf(videocodec_buf + i, size -i - 1, "(connected as)\n");
+
+ h = codeclist_top;
+ while (h) {
+ if (i > (size - LINESIZE))
+ break; // security check
+ i += scnprintf(videocodec_buf + i, size -i -1,
+ "S %32s %04x %08lx %08lx (TEMPLATE)\n",
+ h->codec->name, h->codec->type,
+ h->codec->flags, h->codec->magic);
+ a = h->list;
+ while (a) {
+ if (i > (size - LINESIZE))
+ break; // security check
+ i += scnprintf(videocodec_buf + i, size -i -1,
+ "M %32s %04x %08lx %08lx (%s)\n",
+ a->codec->master_data->name,
+ a->codec->master_data->type,
+ a->codec->master_data->flags,
+ a->codec->master_data->magic,
+ a->codec->name);
+ a = a->next;
+ }
+ h = h->next;
+ }
+
+ return i;
+}
+
+//The definition:
+//typedef int (read_proc_t)(char *page, char **start, off_t off,
+// int count, int *eof, void *data);
+
+static int
+videocodec_info (char *buffer,
+ char **buffer_location,
+ off_t offset,
+ int buffer_length,
+ int *eof,
+ void *data)
+{
+ int size;
+
+ dprintk(3, "videocodec_info: offset: %ld, len %d / size %d\n",
+ offset, buffer_length, videocodec_bufsize);
+
+ if (offset == 0) {
+ videocodec_bufsize = videocodec_build_table();
+ }
+ if ((offset < 0) || (offset >= videocodec_bufsize)) {
+ dprintk(4,
+ "videocodec_info: call delivers no result, return 0\n");
+ *eof = 1;
+ return 0;
+ }
+
+ if (buffer_length < (videocodec_bufsize - offset)) {
+ dprintk(4, "videocodec_info: %ld needed, %d got\n",
+ videocodec_bufsize - offset, buffer_length);
+ size = buffer_length;
+ } else {
+ dprintk(4, "videocodec_info: last reading of %ld bytes\n",
+ videocodec_bufsize - offset);
+ size = videocodec_bufsize - offset;
+ *eof = 1;
+ }
+
+ memcpy(buffer, videocodec_buf + offset, size);
+ /* doesn't work... */
+ /* copy_to_user(buffer, videocodec_buf+offset, size); */
+ /* *buffer_location = videocodec_buf+offset; */
+
+ return size;
+}
+#endif
+
+/* ===================== */
+/* hook in driver module */
+/* ===================== */
+static int __init
+videocodec_init (void)
+{
+#ifdef CONFIG_PROC_FS
+ static struct proc_dir_entry *videocodec_proc_entry;
+#endif
+
+ printk(KERN_INFO "Linux video codec intermediate layer: %s\n",
+ VIDEOCODEC_VERSION);
+
+#ifdef CONFIG_PROC_FS
+ videocodec_buf = NULL;
+ videocodec_bufsize = 0;
+
+ videocodec_proc_entry = create_proc_entry("videocodecs", 0, NULL);
+ if (videocodec_proc_entry) {
+ videocodec_proc_entry->read_proc = videocodec_info;
+ videocodec_proc_entry->write_proc = NULL;
+ videocodec_proc_entry->data = NULL;
+ videocodec_proc_entry->owner = THIS_MODULE;
+ } else {
+ dprintk(1, KERN_ERR "videocodec: can't init procfs.\n");
+ }
+#endif
+ return 0;
+}
+
+static void __exit
+videocodec_exit (void)
+{
+#ifdef CONFIG_PROC_FS
+ remove_proc_entry("videocodecs", NULL);
+ if (videocodec_buf)
+ kfree(videocodec_buf);
+#endif
+}
+
+EXPORT_SYMBOL(videocodec_attach);
+EXPORT_SYMBOL(videocodec_detach);
+EXPORT_SYMBOL(videocodec_register);
+EXPORT_SYMBOL(videocodec_unregister);
+
+module_init(videocodec_init);
+module_exit(videocodec_exit);
+
+MODULE_AUTHOR("Wolfgang Scherr <scherr@net4you.at>");
+MODULE_DESCRIPTION("Intermediate API module for video codecs "
+ VIDEOCODEC_VERSION);
+MODULE_LICENSE("GPL");
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