Add linux-next specific files for 20110831
[linux-2.6/next.git] / drivers / media / video / v4l2-common.c
blob5c6100fb4072120072d0301ca366ddbb8bf5ed93
1 /*
2 * Video for Linux Two
4 * A generic video device interface for the LINUX operating system
5 * using a set of device structures/vectors for low level operations.
7 * This file replaces the videodev.c file that comes with the
8 * regular kernel distribution.
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
15 * Author: Bill Dirks <bill@thedirks.org>
16 * based on code by Alan Cox, <alan@cymru.net>
21 * Video capture interface for Linux
23 * A generic video device interface for the LINUX operating system
24 * using a set of device structures/vectors for low level operations.
26 * This program is free software; you can redistribute it and/or
27 * modify it under the terms of the GNU General Public License
28 * as published by the Free Software Foundation; either version
29 * 2 of the License, or (at your option) any later version.
31 * Author: Alan Cox, <alan@lxorguk.ukuu.org.uk>
33 * Fixes:
37 * Video4linux 1/2 integration by Justin Schoeman
38 * <justin@suntiger.ee.up.ac.za>
39 * 2.4 PROCFS support ported from 2.4 kernels by
40 * Iñaki García Etxebarria <garetxe@euskalnet.net>
41 * Makefile fix by "W. Michael Petullo" <mike@flyn.org>
42 * 2.4 devfs support ported from 2.4 kernels by
43 * Dan Merillat <dan@merillat.org>
44 * Added Gerd Knorrs v4l1 enhancements (Justin Schoeman)
47 #include <linux/module.h>
48 #include <linux/types.h>
49 #include <linux/kernel.h>
50 #include <linux/mm.h>
51 #include <linux/string.h>
52 #include <linux/errno.h>
53 #include <linux/i2c.h>
54 #if defined(CONFIG_SPI)
55 #include <linux/spi/spi.h>
56 #endif
57 #include <asm/uaccess.h>
58 #include <asm/system.h>
59 #include <asm/pgtable.h>
60 #include <asm/io.h>
61 #include <asm/div64.h>
62 #include <media/v4l2-common.h>
63 #include <media/v4l2-device.h>
64 #include <media/v4l2-ctrls.h>
65 #include <media/v4l2-chip-ident.h>
67 #include <linux/videodev2.h>
69 MODULE_AUTHOR("Bill Dirks, Justin Schoeman, Gerd Knorr");
70 MODULE_DESCRIPTION("misc helper functions for v4l2 device drivers");
71 MODULE_LICENSE("GPL");
75 * V 4 L 2 D R I V E R H E L P E R A P I
80 * Video Standard Operations (contributed by Michael Schimek)
83 /* Helper functions for control handling */
85 /* Check for correctness of the ctrl's value based on the data from
86 struct v4l2_queryctrl and the available menu items. Note that
87 menu_items may be NULL, in that case it is ignored. */
88 int v4l2_ctrl_check(struct v4l2_ext_control *ctrl, struct v4l2_queryctrl *qctrl,
89 const char * const *menu_items)
91 if (qctrl->flags & V4L2_CTRL_FLAG_DISABLED)
92 return -EINVAL;
93 if (qctrl->flags & V4L2_CTRL_FLAG_GRABBED)
94 return -EBUSY;
95 if (qctrl->type == V4L2_CTRL_TYPE_STRING)
96 return 0;
97 if (qctrl->type == V4L2_CTRL_TYPE_BUTTON ||
98 qctrl->type == V4L2_CTRL_TYPE_INTEGER64 ||
99 qctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS)
100 return 0;
101 if (ctrl->value < qctrl->minimum || ctrl->value > qctrl->maximum)
102 return -ERANGE;
103 if (qctrl->type == V4L2_CTRL_TYPE_MENU && menu_items != NULL) {
104 if (menu_items[ctrl->value] == NULL ||
105 menu_items[ctrl->value][0] == '\0')
106 return -EINVAL;
108 if (qctrl->type == V4L2_CTRL_TYPE_BITMASK &&
109 (ctrl->value & ~qctrl->maximum))
110 return -ERANGE;
111 return 0;
113 EXPORT_SYMBOL(v4l2_ctrl_check);
115 /* Fill in a struct v4l2_queryctrl */
116 int v4l2_ctrl_query_fill(struct v4l2_queryctrl *qctrl, s32 min, s32 max, s32 step, s32 def)
118 const char *name;
120 v4l2_ctrl_fill(qctrl->id, &name, &qctrl->type,
121 &min, &max, &step, &def, &qctrl->flags);
123 if (name == NULL)
124 return -EINVAL;
126 qctrl->minimum = min;
127 qctrl->maximum = max;
128 qctrl->step = step;
129 qctrl->default_value = def;
130 qctrl->reserved[0] = qctrl->reserved[1] = 0;
131 strlcpy(qctrl->name, name, sizeof(qctrl->name));
132 return 0;
134 EXPORT_SYMBOL(v4l2_ctrl_query_fill);
136 /* Fill in a struct v4l2_querymenu based on the struct v4l2_queryctrl and
137 the menu. The qctrl pointer may be NULL, in which case it is ignored.
138 If menu_items is NULL, then the menu items are retrieved using
139 v4l2_ctrl_get_menu. */
140 int v4l2_ctrl_query_menu(struct v4l2_querymenu *qmenu, struct v4l2_queryctrl *qctrl,
141 const char * const *menu_items)
143 int i;
145 qmenu->reserved = 0;
146 if (menu_items == NULL)
147 menu_items = v4l2_ctrl_get_menu(qmenu->id);
148 if (menu_items == NULL ||
149 (qctrl && (qmenu->index < qctrl->minimum || qmenu->index > qctrl->maximum)))
150 return -EINVAL;
151 for (i = 0; i < qmenu->index && menu_items[i]; i++) ;
152 if (menu_items[i] == NULL || menu_items[i][0] == '\0')
153 return -EINVAL;
154 strlcpy(qmenu->name, menu_items[qmenu->index], sizeof(qmenu->name));
155 return 0;
157 EXPORT_SYMBOL(v4l2_ctrl_query_menu);
159 /* Fill in a struct v4l2_querymenu based on the specified array of valid
160 menu items (terminated by V4L2_CTRL_MENU_IDS_END).
161 Use this if there are 'holes' in the list of valid menu items. */
162 int v4l2_ctrl_query_menu_valid_items(struct v4l2_querymenu *qmenu, const u32 *ids)
164 const char * const *menu_items = v4l2_ctrl_get_menu(qmenu->id);
166 qmenu->reserved = 0;
167 if (menu_items == NULL || ids == NULL)
168 return -EINVAL;
169 while (*ids != V4L2_CTRL_MENU_IDS_END) {
170 if (*ids++ == qmenu->index) {
171 strlcpy(qmenu->name, menu_items[qmenu->index],
172 sizeof(qmenu->name));
173 return 0;
176 return -EINVAL;
178 EXPORT_SYMBOL(v4l2_ctrl_query_menu_valid_items);
180 /* ctrl_classes points to an array of u32 pointers, the last element is
181 a NULL pointer. Each u32 array is a 0-terminated array of control IDs.
182 Each array must be sorted low to high and belong to the same control
183 class. The array of u32 pointers must also be sorted, from low class IDs
184 to high class IDs.
186 This function returns the first ID that follows after the given ID.
187 When no more controls are available 0 is returned. */
188 u32 v4l2_ctrl_next(const u32 * const * ctrl_classes, u32 id)
190 u32 ctrl_class = V4L2_CTRL_ID2CLASS(id);
191 const u32 *pctrl;
193 if (ctrl_classes == NULL)
194 return 0;
196 /* if no query is desired, then check if the ID is part of ctrl_classes */
197 if ((id & V4L2_CTRL_FLAG_NEXT_CTRL) == 0) {
198 /* find class */
199 while (*ctrl_classes && V4L2_CTRL_ID2CLASS(**ctrl_classes) != ctrl_class)
200 ctrl_classes++;
201 if (*ctrl_classes == NULL)
202 return 0;
203 pctrl = *ctrl_classes;
204 /* find control ID */
205 while (*pctrl && *pctrl != id) pctrl++;
206 return *pctrl ? id : 0;
208 id &= V4L2_CTRL_ID_MASK;
209 id++; /* select next control */
210 /* find first class that matches (or is greater than) the class of
211 the ID */
212 while (*ctrl_classes && V4L2_CTRL_ID2CLASS(**ctrl_classes) < ctrl_class)
213 ctrl_classes++;
214 /* no more classes */
215 if (*ctrl_classes == NULL)
216 return 0;
217 pctrl = *ctrl_classes;
218 /* find first ctrl within the class that is >= ID */
219 while (*pctrl && *pctrl < id) pctrl++;
220 if (*pctrl)
221 return *pctrl;
222 /* we are at the end of the controls of the current class. */
223 /* continue with next class if available */
224 ctrl_classes++;
225 if (*ctrl_classes == NULL)
226 return 0;
227 return **ctrl_classes;
229 EXPORT_SYMBOL(v4l2_ctrl_next);
231 int v4l2_chip_match_host(const struct v4l2_dbg_match *match)
233 switch (match->type) {
234 case V4L2_CHIP_MATCH_HOST:
235 return match->addr == 0;
236 default:
237 return 0;
240 EXPORT_SYMBOL(v4l2_chip_match_host);
242 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
243 int v4l2_chip_match_i2c_client(struct i2c_client *c, const struct v4l2_dbg_match *match)
245 int len;
247 if (c == NULL || match == NULL)
248 return 0;
250 switch (match->type) {
251 case V4L2_CHIP_MATCH_I2C_DRIVER:
252 if (c->driver == NULL || c->driver->driver.name == NULL)
253 return 0;
254 len = strlen(c->driver->driver.name);
255 /* legacy drivers have a ' suffix, don't try to match that */
256 if (len && c->driver->driver.name[len - 1] == '\'')
257 len--;
258 return len && !strncmp(c->driver->driver.name, match->name, len);
259 case V4L2_CHIP_MATCH_I2C_ADDR:
260 return c->addr == match->addr;
261 default:
262 return 0;
265 EXPORT_SYMBOL(v4l2_chip_match_i2c_client);
267 int v4l2_chip_ident_i2c_client(struct i2c_client *c, struct v4l2_dbg_chip_ident *chip,
268 u32 ident, u32 revision)
270 if (!v4l2_chip_match_i2c_client(c, &chip->match))
271 return 0;
272 if (chip->ident == V4L2_IDENT_NONE) {
273 chip->ident = ident;
274 chip->revision = revision;
276 else {
277 chip->ident = V4L2_IDENT_AMBIGUOUS;
278 chip->revision = 0;
280 return 0;
282 EXPORT_SYMBOL(v4l2_chip_ident_i2c_client);
284 /* ----------------------------------------------------------------- */
286 /* I2C Helper functions */
289 void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client,
290 const struct v4l2_subdev_ops *ops)
292 v4l2_subdev_init(sd, ops);
293 sd->flags |= V4L2_SUBDEV_FL_IS_I2C;
294 /* the owner is the same as the i2c_client's driver owner */
295 sd->owner = client->driver->driver.owner;
296 /* i2c_client and v4l2_subdev point to one another */
297 v4l2_set_subdevdata(sd, client);
298 i2c_set_clientdata(client, sd);
299 /* initialize name */
300 snprintf(sd->name, sizeof(sd->name), "%s %d-%04x",
301 client->driver->driver.name, i2c_adapter_id(client->adapter),
302 client->addr);
304 EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init);
308 /* Load an i2c sub-device. */
309 struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev,
310 struct i2c_adapter *adapter, struct i2c_board_info *info,
311 const unsigned short *probe_addrs)
313 struct v4l2_subdev *sd = NULL;
314 struct i2c_client *client;
316 BUG_ON(!v4l2_dev);
318 request_module(I2C_MODULE_PREFIX "%s", info->type);
320 /* Create the i2c client */
321 if (info->addr == 0 && probe_addrs)
322 client = i2c_new_probed_device(adapter, info, probe_addrs,
323 NULL);
324 else
325 client = i2c_new_device(adapter, info);
327 /* Note: by loading the module first we are certain that c->driver
328 will be set if the driver was found. If the module was not loaded
329 first, then the i2c core tries to delay-load the module for us,
330 and then c->driver is still NULL until the module is finally
331 loaded. This delay-load mechanism doesn't work if other drivers
332 want to use the i2c device, so explicitly loading the module
333 is the best alternative. */
334 if (client == NULL || client->driver == NULL)
335 goto error;
337 /* Lock the module so we can safely get the v4l2_subdev pointer */
338 if (!try_module_get(client->driver->driver.owner))
339 goto error;
340 sd = i2c_get_clientdata(client);
342 /* Register with the v4l2_device which increases the module's
343 use count as well. */
344 if (v4l2_device_register_subdev(v4l2_dev, sd))
345 sd = NULL;
346 /* Decrease the module use count to match the first try_module_get. */
347 module_put(client->driver->driver.owner);
349 error:
350 /* If we have a client but no subdev, then something went wrong and
351 we must unregister the client. */
352 if (client && sd == NULL)
353 i2c_unregister_device(client);
354 return sd;
356 EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_board);
358 struct v4l2_subdev *v4l2_i2c_new_subdev(struct v4l2_device *v4l2_dev,
359 struct i2c_adapter *adapter, const char *client_type,
360 u8 addr, const unsigned short *probe_addrs)
362 struct i2c_board_info info;
364 /* Setup the i2c board info with the device type and
365 the device address. */
366 memset(&info, 0, sizeof(info));
367 strlcpy(info.type, client_type, sizeof(info.type));
368 info.addr = addr;
370 return v4l2_i2c_new_subdev_board(v4l2_dev, adapter, &info, probe_addrs);
372 EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev);
374 /* Return i2c client address of v4l2_subdev. */
375 unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd)
377 struct i2c_client *client = v4l2_get_subdevdata(sd);
379 return client ? client->addr : I2C_CLIENT_END;
381 EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_addr);
383 /* Return a list of I2C tuner addresses to probe. Use only if the tuner
384 addresses are unknown. */
385 const unsigned short *v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type)
387 static const unsigned short radio_addrs[] = {
388 #if defined(CONFIG_MEDIA_TUNER_TEA5761) || defined(CONFIG_MEDIA_TUNER_TEA5761_MODULE)
389 0x10,
390 #endif
391 0x60,
392 I2C_CLIENT_END
394 static const unsigned short demod_addrs[] = {
395 0x42, 0x43, 0x4a, 0x4b,
396 I2C_CLIENT_END
398 static const unsigned short tv_addrs[] = {
399 0x42, 0x43, 0x4a, 0x4b, /* tda8290 */
400 0x60, 0x61, 0x62, 0x63, 0x64,
401 I2C_CLIENT_END
404 switch (type) {
405 case ADDRS_RADIO:
406 return radio_addrs;
407 case ADDRS_DEMOD:
408 return demod_addrs;
409 case ADDRS_TV:
410 return tv_addrs;
411 case ADDRS_TV_WITH_DEMOD:
412 return tv_addrs + 4;
414 return NULL;
416 EXPORT_SYMBOL_GPL(v4l2_i2c_tuner_addrs);
418 #endif /* defined(CONFIG_I2C) */
420 #if defined(CONFIG_SPI)
422 /* Load a spi sub-device. */
424 void v4l2_spi_subdev_init(struct v4l2_subdev *sd, struct spi_device *spi,
425 const struct v4l2_subdev_ops *ops)
427 v4l2_subdev_init(sd, ops);
428 sd->flags |= V4L2_SUBDEV_FL_IS_SPI;
429 /* the owner is the same as the spi_device's driver owner */
430 sd->owner = spi->dev.driver->owner;
431 /* spi_device and v4l2_subdev point to one another */
432 v4l2_set_subdevdata(sd, spi);
433 spi_set_drvdata(spi, sd);
434 /* initialize name */
435 strlcpy(sd->name, spi->dev.driver->name, sizeof(sd->name));
437 EXPORT_SYMBOL_GPL(v4l2_spi_subdev_init);
439 struct v4l2_subdev *v4l2_spi_new_subdev(struct v4l2_device *v4l2_dev,
440 struct spi_master *master, struct spi_board_info *info)
442 struct v4l2_subdev *sd = NULL;
443 struct spi_device *spi = NULL;
445 BUG_ON(!v4l2_dev);
447 if (info->modalias)
448 request_module(info->modalias);
450 spi = spi_new_device(master, info);
452 if (spi == NULL || spi->dev.driver == NULL)
453 goto error;
455 if (!try_module_get(spi->dev.driver->owner))
456 goto error;
458 sd = spi_get_drvdata(spi);
460 /* Register with the v4l2_device which increases the module's
461 use count as well. */
462 if (v4l2_device_register_subdev(v4l2_dev, sd))
463 sd = NULL;
465 /* Decrease the module use count to match the first try_module_get. */
466 module_put(spi->dev.driver->owner);
468 error:
469 /* If we have a client but no subdev, then something went wrong and
470 we must unregister the client. */
471 if (spi && sd == NULL)
472 spi_unregister_device(spi);
474 return sd;
476 EXPORT_SYMBOL_GPL(v4l2_spi_new_subdev);
478 #endif /* defined(CONFIG_SPI) */
480 /* Clamp x to be between min and max, aligned to a multiple of 2^align. min
481 * and max don't have to be aligned, but there must be at least one valid
482 * value. E.g., min=17,max=31,align=4 is not allowed as there are no multiples
483 * of 16 between 17 and 31. */
484 static unsigned int clamp_align(unsigned int x, unsigned int min,
485 unsigned int max, unsigned int align)
487 /* Bits that must be zero to be aligned */
488 unsigned int mask = ~((1 << align) - 1);
490 /* Round to nearest aligned value */
491 if (align)
492 x = (x + (1 << (align - 1))) & mask;
494 /* Clamp to aligned value of min and max */
495 if (x < min)
496 x = (min + ~mask) & mask;
497 else if (x > max)
498 x = max & mask;
500 return x;
503 /* Bound an image to have a width between wmin and wmax, and height between
504 * hmin and hmax, inclusive. Additionally, the width will be a multiple of
505 * 2^walign, the height will be a multiple of 2^halign, and the overall size
506 * (width*height) will be a multiple of 2^salign. The image may be shrunk
507 * or enlarged to fit the alignment constraints.
509 * The width or height maximum must not be smaller than the corresponding
510 * minimum. The alignments must not be so high there are no possible image
511 * sizes within the allowed bounds. wmin and hmin must be at least 1
512 * (don't use 0). If you don't care about a certain alignment, specify 0,
513 * as 2^0 is 1 and one byte alignment is equivalent to no alignment. If
514 * you only want to adjust downward, specify a maximum that's the same as
515 * the initial value.
517 void v4l_bound_align_image(u32 *w, unsigned int wmin, unsigned int wmax,
518 unsigned int walign,
519 u32 *h, unsigned int hmin, unsigned int hmax,
520 unsigned int halign, unsigned int salign)
522 *w = clamp_align(*w, wmin, wmax, walign);
523 *h = clamp_align(*h, hmin, hmax, halign);
525 /* Usually we don't need to align the size and are done now. */
526 if (!salign)
527 return;
529 /* How much alignment do we have? */
530 walign = __ffs(*w);
531 halign = __ffs(*h);
532 /* Enough to satisfy the image alignment? */
533 if (walign + halign < salign) {
534 /* Max walign where there is still a valid width */
535 unsigned int wmaxa = __fls(wmax ^ (wmin - 1));
536 /* Max halign where there is still a valid height */
537 unsigned int hmaxa = __fls(hmax ^ (hmin - 1));
539 /* up the smaller alignment until we have enough */
540 do {
541 if (halign >= hmaxa ||
542 (walign <= halign && walign < wmaxa)) {
543 *w = clamp_align(*w, wmin, wmax, walign + 1);
544 walign = __ffs(*w);
545 } else {
546 *h = clamp_align(*h, hmin, hmax, halign + 1);
547 halign = __ffs(*h);
549 } while (halign + walign < salign);
552 EXPORT_SYMBOL_GPL(v4l_bound_align_image);
555 * v4l_fill_dv_preset_info - fill description of a digital video preset
556 * @preset - preset value
557 * @info - pointer to struct v4l2_dv_enum_preset
559 * drivers can use this helper function to fill description of dv preset
560 * in info.
562 int v4l_fill_dv_preset_info(u32 preset, struct v4l2_dv_enum_preset *info)
564 static const struct v4l2_dv_preset_info {
565 u16 width;
566 u16 height;
567 const char *name;
568 } dv_presets[] = {
569 { 0, 0, "Invalid" }, /* V4L2_DV_INVALID */
570 { 720, 480, "480p@59.94" }, /* V4L2_DV_480P59_94 */
571 { 720, 576, "576p@50" }, /* V4L2_DV_576P50 */
572 { 1280, 720, "720p@24" }, /* V4L2_DV_720P24 */
573 { 1280, 720, "720p@25" }, /* V4L2_DV_720P25 */
574 { 1280, 720, "720p@30" }, /* V4L2_DV_720P30 */
575 { 1280, 720, "720p@50" }, /* V4L2_DV_720P50 */
576 { 1280, 720, "720p@59.94" }, /* V4L2_DV_720P59_94 */
577 { 1280, 720, "720p@60" }, /* V4L2_DV_720P60 */
578 { 1920, 1080, "1080i@29.97" }, /* V4L2_DV_1080I29_97 */
579 { 1920, 1080, "1080i@30" }, /* V4L2_DV_1080I30 */
580 { 1920, 1080, "1080i@25" }, /* V4L2_DV_1080I25 */
581 { 1920, 1080, "1080i@50" }, /* V4L2_DV_1080I50 */
582 { 1920, 1080, "1080i@60" }, /* V4L2_DV_1080I60 */
583 { 1920, 1080, "1080p@24" }, /* V4L2_DV_1080P24 */
584 { 1920, 1080, "1080p@25" }, /* V4L2_DV_1080P25 */
585 { 1920, 1080, "1080p@30" }, /* V4L2_DV_1080P30 */
586 { 1920, 1080, "1080p@50" }, /* V4L2_DV_1080P50 */
587 { 1920, 1080, "1080p@60" }, /* V4L2_DV_1080P60 */
590 if (info == NULL || preset >= ARRAY_SIZE(dv_presets))
591 return -EINVAL;
593 info->preset = preset;
594 info->width = dv_presets[preset].width;
595 info->height = dv_presets[preset].height;
596 strlcpy(info->name, dv_presets[preset].name, sizeof(info->name));
597 return 0;
599 EXPORT_SYMBOL_GPL(v4l_fill_dv_preset_info);
601 const struct v4l2_frmsize_discrete *v4l2_find_nearest_format(
602 const struct v4l2_discrete_probe *probe,
603 s32 width, s32 height)
605 int i;
606 u32 error, min_error = UINT_MAX;
607 const struct v4l2_frmsize_discrete *size, *best = NULL;
609 if (!probe)
610 return best;
612 for (i = 0, size = probe->sizes; i < probe->num_sizes; i++, size++) {
613 error = abs(size->width - width) + abs(size->height - height);
614 if (error < min_error) {
615 min_error = error;
616 best = size;
618 if (!error)
619 break;
622 return best;
624 EXPORT_SYMBOL_GPL(v4l2_find_nearest_format);