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30#define VIDEOCODEC_VERSION "v0.2"
31
32#include <linux/kernel.h>
33#include <linux/module.h>
34#include <linux/init.h>
35#include <linux/types.h>
36#include <linux/slab.h>
37
38
39
40#ifdef CONFIG_PROC_FS
41#include <linux/proc_fs.h>
42#include <linux/seq_file.h>
43#include <asm/uaccess.h>
44#endif
45
46#include "videocodec.h"
47
48static int debug;
49module_param(debug, int, 0);
50MODULE_PARM_DESC(debug, "Debug level (0-4)");
51
52#define dprintk(num, format, args...) \
53 do { \
54 if (debug >= num) \
55 printk(format, ##args); \
56 } while (0)
57
58struct attached_list {
59 struct videocodec *codec;
60 struct attached_list *next;
61};
62
63struct codec_list {
64 const struct videocodec *codec;
65 int attached;
66 struct attached_list *list;
67 struct codec_list *next;
68};
69
70static struct codec_list *codeclist_top = NULL;
71
72
73
74
75
76struct videocodec *
77videocodec_attach (struct videocodec_master *master)
78{
79 struct codec_list *h = codeclist_top;
80 struct attached_list *a, *ptr;
81 struct videocodec *codec;
82 int res;
83
84 if (!master) {
85 dprintk(1, KERN_ERR "videocodec_attach: no data\n");
86 return NULL;
87 }
88
89 dprintk(2,
90 "videocodec_attach: '%s', flags %lx, magic %lx\n",
91 master->name, master->flags, master->magic);
92
93 if (!h) {
94 dprintk(1,
95 KERN_ERR
96 "videocodec_attach: no device available\n");
97 return NULL;
98 }
99
100 while (h) {
101
102
103 if ((master->flags & h->codec->flags) == master->flags) {
104 dprintk(4, "videocodec_attach: try '%s'\n",
105 h->codec->name);
106
107 if (!try_module_get(h->codec->owner))
108 return NULL;
109
110 codec = kmemdup(h->codec, sizeof(struct videocodec),
111 GFP_KERNEL);
112 if (!codec) {
113 dprintk(1,
114 KERN_ERR
115 "videocodec_attach: no mem\n");
116 goto out_module_put;
117 }
118
119 res = strlen(codec->name);
120 snprintf(codec->name + res, sizeof(codec->name) - res,
121 "[%d]", h->attached);
122 codec->master_data = master;
123 res = codec->setup(codec);
124 if (res == 0) {
125 dprintk(3, "videocodec_attach '%s'\n",
126 codec->name);
127 ptr = kzalloc(sizeof(struct attached_list), GFP_KERNEL);
128 if (!ptr) {
129 dprintk(1,
130 KERN_ERR
131 "videocodec_attach: no memory\n");
132 goto out_kfree;
133 }
134 ptr->codec = codec;
135
136 a = h->list;
137 if (!a) {
138 h->list = ptr;
139 dprintk(4,
140 "videocodec: first element\n");
141 } else {
142 while (a->next)
143 a = a->next;
144 a->next = ptr;
145 dprintk(4,
146 "videocodec: in after '%s'\n",
147 h->codec->name);
148 }
149
150 h->attached += 1;
151 return codec;
152 } else {
153 kfree(codec);
154 }
155 }
156 h = h->next;
157 }
158
159 dprintk(1, KERN_ERR "videocodec_attach: no codec found!\n");
160 return NULL;
161
162 out_module_put:
163 module_put(h->codec->owner);
164 out_kfree:
165 kfree(codec);
166 return NULL;
167}
168
169int
170videocodec_detach (struct videocodec *codec)
171{
172 struct codec_list *h = codeclist_top;
173 struct attached_list *a, *prev;
174 int res;
175
176 if (!codec) {
177 dprintk(1, KERN_ERR "videocodec_detach: no data\n");
178 return -EINVAL;
179 }
180
181 dprintk(2,
182 "videocodec_detach: '%s', type: %x, flags %lx, magic %lx\n",
183 codec->name, codec->type, codec->flags, codec->magic);
184
185 if (!h) {
186 dprintk(1,
187 KERN_ERR "videocodec_detach: no device left...\n");
188 return -ENXIO;
189 }
190
191 while (h) {
192 a = h->list;
193 prev = NULL;
194 while (a) {
195 if (codec == a->codec) {
196 res = a->codec->unset(a->codec);
197 if (res >= 0) {
198 dprintk(3,
199 "videocodec_detach: '%s'\n",
200 a->codec->name);
201 a->codec->master_data = NULL;
202 } else {
203 dprintk(1,
204 KERN_ERR
205 "videocodec_detach: '%s'\n",
206 a->codec->name);
207 a->codec->master_data = NULL;
208 }
209 if (prev == NULL) {
210 h->list = a->next;
211 dprintk(4,
212 "videocodec: delete first\n");
213 } else {
214 prev->next = a->next;
215 dprintk(4,
216 "videocodec: delete middle\n");
217 }
218 module_put(a->codec->owner);
219 kfree(a->codec);
220 kfree(a);
221 h->attached -= 1;
222 return 0;
223 }
224 prev = a;
225 a = a->next;
226 }
227 h = h->next;
228 }
229
230 dprintk(1, KERN_ERR "videocodec_detach: given codec not found!\n");
231 return -EINVAL;
232}
233
234int
235videocodec_register (const struct videocodec *codec)
236{
237 struct codec_list *ptr, *h = codeclist_top;
238
239 if (!codec) {
240 dprintk(1, KERN_ERR "videocodec_register: no data!\n");
241 return -EINVAL;
242 }
243
244 dprintk(2,
245 "videocodec: register '%s', type: %x, flags %lx, magic %lx\n",
246 codec->name, codec->type, codec->flags, codec->magic);
247
248 ptr = kzalloc(sizeof(struct codec_list), GFP_KERNEL);
249 if (!ptr) {
250 dprintk(1, KERN_ERR "videocodec_register: no memory\n");
251 return -ENOMEM;
252 }
253 ptr->codec = codec;
254
255 if (!h) {
256 codeclist_top = ptr;
257 dprintk(4, "videocodec: hooked in as first element\n");
258 } else {
259 while (h->next)
260 h = h->next;
261 h->next = ptr;
262 dprintk(4, "videocodec: hooked in after '%s'\n",
263 h->codec->name);
264 }
265
266 return 0;
267}
268
269int
270videocodec_unregister (const struct videocodec *codec)
271{
272 struct codec_list *prev = NULL, *h = codeclist_top;
273
274 if (!codec) {
275 dprintk(1, KERN_ERR "videocodec_unregister: no data!\n");
276 return -EINVAL;
277 }
278
279 dprintk(2,
280 "videocodec: unregister '%s', type: %x, flags %lx, magic %lx\n",
281 codec->name, codec->type, codec->flags, codec->magic);
282
283 if (!h) {
284 dprintk(1,
285 KERN_ERR
286 "videocodec_unregister: no device left...\n");
287 return -ENXIO;
288 }
289
290 while (h) {
291 if (codec == h->codec) {
292 if (h->attached) {
293 dprintk(1,
294 KERN_ERR
295 "videocodec: '%s' is used\n",
296 h->codec->name);
297 return -EBUSY;
298 }
299 dprintk(3, "videocodec: unregister '%s' is ok.\n",
300 h->codec->name);
301 if (prev == NULL) {
302 codeclist_top = h->next;
303 dprintk(4,
304 "videocodec: delete first element\n");
305 } else {
306 prev->next = h->next;
307 dprintk(4,
308 "videocodec: delete middle element\n");
309 }
310 kfree(h);
311 return 0;
312 }
313 prev = h;
314 h = h->next;
315 }
316
317 dprintk(1,
318 KERN_ERR
319 "videocodec_unregister: given codec not found!\n");
320 return -EINVAL;
321}
322
323#ifdef CONFIG_PROC_FS
324static int proc_videocodecs_show(struct seq_file *m, void *v)
325{
326 struct codec_list *h = codeclist_top;
327 struct attached_list *a;
328
329 seq_printf(m, "<S>lave or attached <M>aster name type flags magic ");
330 seq_printf(m, "(connected as)\n");
331
332 h = codeclist_top;
333 while (h) {
334 seq_printf(m, "S %32s %04x %08lx %08lx (TEMPLATE)\n",
335 h->codec->name, h->codec->type,
336 h->codec->flags, h->codec->magic);
337 a = h->list;
338 while (a) {
339 seq_printf(m, "M %32s %04x %08lx %08lx (%s)\n",
340 a->codec->master_data->name,
341 a->codec->master_data->type,
342 a->codec->master_data->flags,
343 a->codec->master_data->magic,
344 a->codec->name);
345 a = a->next;
346 }
347 h = h->next;
348 }
349
350 return 0;
351}
352
353static int proc_videocodecs_open(struct inode *inode, struct file *file)
354{
355 return single_open(file, proc_videocodecs_show, NULL);
356}
357
358static const struct file_operations videocodecs_proc_fops = {
359 .owner = THIS_MODULE,
360 .open = proc_videocodecs_open,
361 .read = seq_read,
362 .llseek = seq_lseek,
363 .release = single_release,
364};
365#endif
366
367
368
369
370static int __init
371videocodec_init (void)
372{
373#ifdef CONFIG_PROC_FS
374 static struct proc_dir_entry *videocodec_proc_entry;
375#endif
376
377 printk(KERN_INFO "Linux video codec intermediate layer: %s\n",
378 VIDEOCODEC_VERSION);
379
380#ifdef CONFIG_PROC_FS
381 videocodec_proc_entry = proc_create("videocodecs", 0, NULL, &videocodecs_proc_fops);
382 if (!videocodec_proc_entry) {
383 dprintk(1, KERN_ERR "videocodec: can't init procfs.\n");
384 }
385#endif
386 return 0;
387}
388
389static void __exit
390videocodec_exit (void)
391{
392#ifdef CONFIG_PROC_FS
393 remove_proc_entry("videocodecs", NULL);
394#endif
395}
396
397EXPORT_SYMBOL(videocodec_attach);
398EXPORT_SYMBOL(videocodec_detach);
399EXPORT_SYMBOL(videocodec_register);
400EXPORT_SYMBOL(videocodec_unregister);
401
402module_init(videocodec_init);
403module_exit(videocodec_exit);
404
405MODULE_AUTHOR("Wolfgang Scherr <scherr@net4you.at>");
406MODULE_DESCRIPTION("Intermediate API module for video codecs "
407 VIDEOCODEC_VERSION);
408MODULE_LICENSE("GPL");
409
