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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 snprintf(codec->name, sizeof(codec->name),
120 "%s[%d]", codec->name, h->attached);
121 codec->master_data = master;
122 res = codec->setup(codec);
123 if (res == 0) {
124 dprintk(3, "videocodec_attach '%s'\n",
125 codec->name);
126 ptr = kzalloc(sizeof(struct attached_list), GFP_KERNEL);
127 if (!ptr) {
128 dprintk(1,
129 KERN_ERR
130 "videocodec_attach: no memory\n");
131 goto out_kfree;
132 }
133 ptr->codec = codec;
134
135 a = h->list;
136 if (!a) {
137 h->list = ptr;
138 dprintk(4,
139 "videocodec: first element\n");
140 } else {
141 while (a->next)
142 a = a->next;
143 a->next = ptr;
144 dprintk(4,
145 "videocodec: in after '%s'\n",
146 h->codec->name);
147 }
148
149 h->attached += 1;
150 return codec;
151 } else {
152 kfree(codec);
153 }
154 }
155 h = h->next;
156 }
157
158 dprintk(1, KERN_ERR "videocodec_attach: no codec found!\n");
159 return NULL;
160
161 out_module_put:
162 module_put(h->codec->owner);
163 out_kfree:
164 kfree(codec);
165 return NULL;
166}
167
168int
169videocodec_detach (struct videocodec *codec)
170{
171 struct codec_list *h = codeclist_top;
172 struct attached_list *a, *prev;
173 int res;
174
175 if (!codec) {
176 dprintk(1, KERN_ERR "videocodec_detach: no data\n");
177 return -EINVAL;
178 }
179
180 dprintk(2,
181 "videocodec_detach: '%s', type: %x, flags %lx, magic %lx\n",
182 codec->name, codec->type, codec->flags, codec->magic);
183
184 if (!h) {
185 dprintk(1,
186 KERN_ERR "videocodec_detach: no device left...\n");
187 return -ENXIO;
188 }
189
190 while (h) {
191 a = h->list;
192 prev = NULL;
193 while (a) {
194 if (codec == a->codec) {
195 res = a->codec->unset(a->codec);
196 if (res >= 0) {
197 dprintk(3,
198 "videocodec_detach: '%s'\n",
199 a->codec->name);
200 a->codec->master_data = NULL;
201 } else {
202 dprintk(1,
203 KERN_ERR
204 "videocodec_detach: '%s'\n",
205 a->codec->name);
206 a->codec->master_data = NULL;
207 }
208 if (prev == NULL) {
209 h->list = a->next;
210 dprintk(4,
211 "videocodec: delete first\n");
212 } else {
213 prev->next = a->next;
214 dprintk(4,
215 "videocodec: delete middle\n");
216 }
217 module_put(a->codec->owner);
218 kfree(a->codec);
219 kfree(a);
220 h->attached -= 1;
221 return 0;
222 }
223 prev = a;
224 a = a->next;
225 }
226 h = h->next;
227 }
228
229 dprintk(1, KERN_ERR "videocodec_detach: given codec not found!\n");
230 return -EINVAL;
231}
232
233int
234videocodec_register (const struct videocodec *codec)
235{
236 struct codec_list *ptr, *h = codeclist_top;
237
238 if (!codec) {
239 dprintk(1, KERN_ERR "videocodec_register: no data!\n");
240 return -EINVAL;
241 }
242
243 dprintk(2,
244 "videocodec: register '%s', type: %x, flags %lx, magic %lx\n",
245 codec->name, codec->type, codec->flags, codec->magic);
246
247 ptr = kzalloc(sizeof(struct codec_list), GFP_KERNEL);
248 if (!ptr) {
249 dprintk(1, KERN_ERR "videocodec_register: no memory\n");
250 return -ENOMEM;
251 }
252 ptr->codec = codec;
253
254 if (!h) {
255 codeclist_top = ptr;
256 dprintk(4, "videocodec: hooked in as first element\n");
257 } else {
258 while (h->next)
259 h = h->next;
260 h->next = ptr;
261 dprintk(4, "videocodec: hooked in after '%s'\n",
262 h->codec->name);
263 }
264
265 return 0;
266}
267
268int
269videocodec_unregister (const struct videocodec *codec)
270{
271 struct codec_list *prev = NULL, *h = codeclist_top;
272
273 if (!codec) {
274 dprintk(1, KERN_ERR "videocodec_unregister: no data!\n");
275 return -EINVAL;
276 }
277
278 dprintk(2,
279 "videocodec: unregister '%s', type: %x, flags %lx, magic %lx\n",
280 codec->name, codec->type, codec->flags, codec->magic);
281
282 if (!h) {
283 dprintk(1,
284 KERN_ERR
285 "videocodec_unregister: no device left...\n");
286 return -ENXIO;
287 }
288
289 while (h) {
290 if (codec == h->codec) {
291 if (h->attached) {
292 dprintk(1,
293 KERN_ERR
294 "videocodec: '%s' is used\n",
295 h->codec->name);
296 return -EBUSY;
297 }
298 dprintk(3, "videocodec: unregister '%s' is ok.\n",
299 h->codec->name);
300 if (prev == NULL) {
301 codeclist_top = h->next;
302 dprintk(4,
303 "videocodec: delete first element\n");
304 } else {
305 prev->next = h->next;
306 dprintk(4,
307 "videocodec: delete middle element\n");
308 }
309 kfree(h);
310 return 0;
311 }
312 prev = h;
313 h = h->next;
314 }
315
316 dprintk(1,
317 KERN_ERR
318 "videocodec_unregister: given codec not found!\n");
319 return -EINVAL;
320}
321
322#ifdef CONFIG_PROC_FS
323static int proc_videocodecs_show(struct seq_file *m, void *v)
324{
325 struct codec_list *h = codeclist_top;
326 struct attached_list *a;
327
328 seq_printf(m, "<S>lave or attached <M>aster name type flags magic ");
329 seq_printf(m, "(connected as)\n");
330
331 h = codeclist_top;
332 while (h) {
333 seq_printf(m, "S %32s %04x %08lx %08lx (TEMPLATE)\n",
334 h->codec->name, h->codec->type,
335 h->codec->flags, h->codec->magic);
336 a = h->list;
337 while (a) {
338 seq_printf(m, "M %32s %04x %08lx %08lx (%s)\n",
339 a->codec->master_data->name,
340 a->codec->master_data->type,
341 a->codec->master_data->flags,
342 a->codec->master_data->magic,
343 a->codec->name);
344 a = a->next;
345 }
346 h = h->next;
347 }
348
349 return 0;
350}
351
352static int proc_videocodecs_open(struct inode *inode, struct file *file)
353{
354 return single_open(file, proc_videocodecs_show, NULL);
355}
356
357static const struct file_operations videocodecs_proc_fops = {
358 .owner = THIS_MODULE,
359 .open = proc_videocodecs_open,
360 .read = seq_read,
361 .llseek = seq_lseek,
362 .release = single_release,
363};
364#endif
365
366
367
368
369static int __init
370videocodec_init (void)
371{
372#ifdef CONFIG_PROC_FS
373 static struct proc_dir_entry *videocodec_proc_entry;
374#endif
375
376 printk(KERN_INFO "Linux video codec intermediate layer: %s\n",
377 VIDEOCODEC_VERSION);
378
379#ifdef CONFIG_PROC_FS
380 videocodec_proc_entry = proc_create("videocodecs", 0, NULL, &videocodecs_proc_fops);
381 if (!videocodec_proc_entry) {
382 dprintk(1, KERN_ERR "videocodec: can't init procfs.\n");
383 }
384#endif
385 return 0;
386}
387
388static void __exit
389videocodec_exit (void)
390{
391#ifdef CONFIG_PROC_FS
392 remove_proc_entry("videocodecs", NULL);
393#endif
394}
395
396EXPORT_SYMBOL(videocodec_attach);
397EXPORT_SYMBOL(videocodec_detach);
398EXPORT_SYMBOL(videocodec_register);
399EXPORT_SYMBOL(videocodec_unregister);
400
401module_init(videocodec_init);
402module_exit(videocodec_exit);
403
404MODULE_AUTHOR("Wolfgang Scherr <scherr@net4you.at>");
405MODULE_DESCRIPTION("Intermediate API module for video codecs "
406 VIDEOCODEC_VERSION);
407MODULE_LICENSE("GPL");
408
