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26#define VIDEOCODEC_VERSION "v0.2"
27
28#include <linux/kernel.h>
29#include <linux/module.h>
30#include <linux/init.h>
31#include <linux/types.h>
32#include <linux/slab.h>
33
34
35
36#ifdef CONFIG_PROC_FS
37#include <linux/proc_fs.h>
38#include <linux/seq_file.h>
39#include <linux/uaccess.h>
40#endif
41
42#include "videocodec.h"
43
44static int debug;
45module_param(debug, int, 0);
46MODULE_PARM_DESC(debug, "Debug level (0-4)");
47
48#define dprintk(num, format, args...) \
49 do { \
50 if (debug >= num) \
51 printk(format, ##args); \
52 } while (0)
53
54struct attached_list {
55 struct videocodec *codec;
56 struct attached_list *next;
57};
58
59struct codec_list {
60 const struct videocodec *codec;
61 int attached;
62 struct attached_list *list;
63 struct codec_list *next;
64};
65
66static struct codec_list *codeclist_top = NULL;
67
68
69
70
71
72struct videocodec *
73videocodec_attach (struct videocodec_master *master)
74{
75 struct codec_list *h = codeclist_top;
76 struct attached_list *a, *ptr;
77 struct videocodec *codec;
78 int res;
79
80 if (!master) {
81 dprintk(1, KERN_ERR "videocodec_attach: no data\n");
82 return NULL;
83 }
84
85 dprintk(2,
86 "videocodec_attach: '%s', flags %lx, magic %lx\n",
87 master->name, master->flags, master->magic);
88
89 if (!h) {
90 dprintk(1,
91 KERN_ERR
92 "videocodec_attach: no device available\n");
93 return NULL;
94 }
95
96 while (h) {
97
98
99 if ((master->flags & h->codec->flags) == master->flags) {
100 dprintk(4, "videocodec_attach: try '%s'\n",
101 h->codec->name);
102
103 if (!try_module_get(h->codec->owner))
104 return NULL;
105
106 codec = kmemdup(h->codec, sizeof(struct videocodec),
107 GFP_KERNEL);
108 if (!codec) {
109 dprintk(1,
110 KERN_ERR
111 "videocodec_attach: no mem\n");
112 goto out_module_put;
113 }
114
115 res = strlen(codec->name);
116 snprintf(codec->name + res, sizeof(codec->name) - res,
117 "[%d]", h->attached);
118 codec->master_data = master;
119 res = codec->setup(codec);
120 if (res == 0) {
121 dprintk(3, "videocodec_attach '%s'\n",
122 codec->name);
123 ptr = kzalloc(sizeof(struct attached_list), GFP_KERNEL);
124 if (!ptr) {
125 dprintk(1,
126 KERN_ERR
127 "videocodec_attach: no memory\n");
128 goto out_kfree;
129 }
130 ptr->codec = codec;
131
132 a = h->list;
133 if (!a) {
134 h->list = ptr;
135 dprintk(4,
136 "videocodec: first element\n");
137 } else {
138 while (a->next)
139 a = a->next;
140 a->next = ptr;
141 dprintk(4,
142 "videocodec: in after '%s'\n",
143 h->codec->name);
144 }
145
146 h->attached += 1;
147 return codec;
148 } else {
149 kfree(codec);
150 }
151 }
152 h = h->next;
153 }
154
155 dprintk(1, KERN_ERR "videocodec_attach: no codec found!\n");
156 return NULL;
157
158 out_module_put:
159 module_put(h->codec->owner);
160 out_kfree:
161 kfree(codec);
162 return NULL;
163}
164
165int
166videocodec_detach (struct videocodec *codec)
167{
168 struct codec_list *h = codeclist_top;
169 struct attached_list *a, *prev;
170 int res;
171
172 if (!codec) {
173 dprintk(1, KERN_ERR "videocodec_detach: no data\n");
174 return -EINVAL;
175 }
176
177 dprintk(2,
178 "videocodec_detach: '%s', type: %x, flags %lx, magic %lx\n",
179 codec->name, codec->type, codec->flags, codec->magic);
180
181 if (!h) {
182 dprintk(1,
183 KERN_ERR "videocodec_detach: no device left...\n");
184 return -ENXIO;
185 }
186
187 while (h) {
188 a = h->list;
189 prev = NULL;
190 while (a) {
191 if (codec == a->codec) {
192 res = a->codec->unset(a->codec);
193 if (res >= 0) {
194 dprintk(3,
195 "videocodec_detach: '%s'\n",
196 a->codec->name);
197 a->codec->master_data = NULL;
198 } else {
199 dprintk(1,
200 KERN_ERR
201 "videocodec_detach: '%s'\n",
202 a->codec->name);
203 a->codec->master_data = NULL;
204 }
205 if (prev == NULL) {
206 h->list = a->next;
207 dprintk(4,
208 "videocodec: delete first\n");
209 } else {
210 prev->next = a->next;
211 dprintk(4,
212 "videocodec: delete middle\n");
213 }
214 module_put(a->codec->owner);
215 kfree(a->codec);
216 kfree(a);
217 h->attached -= 1;
218 return 0;
219 }
220 prev = a;
221 a = a->next;
222 }
223 h = h->next;
224 }
225
226 dprintk(1, KERN_ERR "videocodec_detach: given codec not found!\n");
227 return -EINVAL;
228}
229
230int
231videocodec_register (const struct videocodec *codec)
232{
233 struct codec_list *ptr, *h = codeclist_top;
234
235 if (!codec) {
236 dprintk(1, KERN_ERR "videocodec_register: no data!\n");
237 return -EINVAL;
238 }
239
240 dprintk(2,
241 "videocodec: register '%s', type: %x, flags %lx, magic %lx\n",
242 codec->name, codec->type, codec->flags, codec->magic);
243
244 ptr = kzalloc(sizeof(struct codec_list), GFP_KERNEL);
245 if (!ptr) {
246 dprintk(1, KERN_ERR "videocodec_register: no memory\n");
247 return -ENOMEM;
248 }
249 ptr->codec = codec;
250
251 if (!h) {
252 codeclist_top = ptr;
253 dprintk(4, "videocodec: hooked in as first element\n");
254 } else {
255 while (h->next)
256 h = h->next;
257 h->next = ptr;
258 dprintk(4, "videocodec: hooked in after '%s'\n",
259 h->codec->name);
260 }
261
262 return 0;
263}
264
265int
266videocodec_unregister (const struct videocodec *codec)
267{
268 struct codec_list *prev = NULL, *h = codeclist_top;
269
270 if (!codec) {
271 dprintk(1, KERN_ERR "videocodec_unregister: no data!\n");
272 return -EINVAL;
273 }
274
275 dprintk(2,
276 "videocodec: unregister '%s', type: %x, flags %lx, magic %lx\n",
277 codec->name, codec->type, codec->flags, codec->magic);
278
279 if (!h) {
280 dprintk(1,
281 KERN_ERR
282 "videocodec_unregister: no device left...\n");
283 return -ENXIO;
284 }
285
286 while (h) {
287 if (codec == h->codec) {
288 if (h->attached) {
289 dprintk(1,
290 KERN_ERR
291 "videocodec: '%s' is used\n",
292 h->codec->name);
293 return -EBUSY;
294 }
295 dprintk(3, "videocodec: unregister '%s' is ok.\n",
296 h->codec->name);
297 if (prev == NULL) {
298 codeclist_top = h->next;
299 dprintk(4,
300 "videocodec: delete first element\n");
301 } else {
302 prev->next = h->next;
303 dprintk(4,
304 "videocodec: delete middle element\n");
305 }
306 kfree(h);
307 return 0;
308 }
309 prev = h;
310 h = h->next;
311 }
312
313 dprintk(1,
314 KERN_ERR
315 "videocodec_unregister: given codec not found!\n");
316 return -EINVAL;
317}
318
319#ifdef CONFIG_PROC_FS
320static int proc_videocodecs_show(struct seq_file *m, void *v)
321{
322 struct codec_list *h = codeclist_top;
323 struct attached_list *a;
324
325 seq_printf(m, "<S>lave or attached <M>aster name type flags magic ");
326 seq_printf(m, "(connected as)\n");
327
328 while (h) {
329 seq_printf(m, "S %32s %04x %08lx %08lx (TEMPLATE)\n",
330 h->codec->name, h->codec->type,
331 h->codec->flags, h->codec->magic);
332 a = h->list;
333 while (a) {
334 seq_printf(m, "M %32s %04x %08lx %08lx (%s)\n",
335 a->codec->master_data->name,
336 a->codec->master_data->type,
337 a->codec->master_data->flags,
338 a->codec->master_data->magic,
339 a->codec->name);
340 a = a->next;
341 }
342 h = h->next;
343 }
344
345 return 0;
346}
347#endif
348
349
350
351
352static int __init
353videocodec_init (void)
354{
355#ifdef CONFIG_PROC_FS
356 static struct proc_dir_entry *videocodec_proc_entry;
357#endif
358
359 printk(KERN_INFO "Linux video codec intermediate layer: %s\n",
360 VIDEOCODEC_VERSION);
361
362#ifdef CONFIG_PROC_FS
363 videocodec_proc_entry = proc_create_single("videocodecs", 0, NULL,
364 proc_videocodecs_show);
365 if (!videocodec_proc_entry) {
366 dprintk(1, KERN_ERR "videocodec: can't init procfs.\n");
367 }
368#endif
369 return 0;
370}
371
372static void __exit
373videocodec_exit (void)
374{
375#ifdef CONFIG_PROC_FS
376 remove_proc_entry("videocodecs", NULL);
377#endif
378}
379
380EXPORT_SYMBOL(videocodec_attach);
381EXPORT_SYMBOL(videocodec_detach);
382EXPORT_SYMBOL(videocodec_register);
383EXPORT_SYMBOL(videocodec_unregister);
384
385module_init(videocodec_init);
386module_exit(videocodec_exit);
387
388MODULE_AUTHOR("Wolfgang Scherr <scherr@net4you.at>");
389MODULE_DESCRIPTION("Intermediate API module for video codecs "
390 VIDEOCODEC_VERSION);
391MODULE_LICENSE("GPL");
392
