| 1 | /* |
| 2 | * Video for Linux Two |
| 3 | * |
| 4 | * A generic video device interface for the LINUX operating system |
| 5 | * using a set of device structures/vectors for low level operations. |
| 6 | * |
| 7 | * This file replaces the videodev.c file that comes with the |
| 8 | * regular kernel distribution. |
| 9 | * |
| 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. |
| 14 | * |
| 15 | * Author: Bill Dirks <bill@thedirks.org> |
| 16 | * based on code by Alan Cox, <alan@cymru.net> |
| 17 | * |
| 18 | */ |
| 19 | |
| 20 | /* |
| 21 | * Video capture interface for Linux |
| 22 | * |
| 23 | * A generic video device interface for the LINUX operating system |
| 24 | * using a set of device structures/vectors for low level operations. |
| 25 | * |
| 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. |
| 30 | * |
| 31 | * Author: Alan Cox, <alan@lxorguk.ukuu.org.uk> |
| 32 | * |
| 33 | * Fixes: |
| 34 | */ |
| 35 | |
| 36 | /* |
| 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) |
| 45 | */ |
| 46 | |
| 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/pgtable.h> |
| 59 | #include <asm/io.h> |
| 60 | #include <asm/div64.h> |
| 61 | #include <media/v4l2-common.h> |
| 62 | #include <media/v4l2-device.h> |
| 63 | #include <media/v4l2-ctrls.h> |
| 64 | |
| 65 | #include <linux/videodev2.h> |
| 66 | |
| 67 | MODULE_AUTHOR("Bill Dirks, Justin Schoeman, Gerd Knorr"); |
| 68 | MODULE_DESCRIPTION("misc helper functions for v4l2 device drivers"); |
| 69 | MODULE_LICENSE("GPL"); |
| 70 | |
| 71 | /* |
| 72 | * |
| 73 | * V 4 L 2 D R I V E R H E L P E R A P I |
| 74 | * |
| 75 | */ |
| 76 | |
| 77 | /* |
| 78 | * Video Standard Operations (contributed by Michael Schimek) |
| 79 | */ |
| 80 | |
| 81 | /* Helper functions for control handling */ |
| 82 | |
| 83 | /* Check for correctness of the ctrl's value based on the data from |
| 84 | struct v4l2_queryctrl and the available menu items. Note that |
| 85 | menu_items may be NULL, in that case it is ignored. */ |
| 86 | int v4l2_ctrl_check(struct v4l2_ext_control *ctrl, struct v4l2_queryctrl *qctrl, |
| 87 | const char * const *menu_items) |
| 88 | { |
| 89 | if (qctrl->flags & V4L2_CTRL_FLAG_DISABLED) |
| 90 | return -EINVAL; |
| 91 | if (qctrl->flags & V4L2_CTRL_FLAG_GRABBED) |
| 92 | return -EBUSY; |
| 93 | if (qctrl->type == V4L2_CTRL_TYPE_STRING) |
| 94 | return 0; |
| 95 | if (qctrl->type == V4L2_CTRL_TYPE_BUTTON || |
| 96 | qctrl->type == V4L2_CTRL_TYPE_INTEGER64 || |
| 97 | qctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS) |
| 98 | return 0; |
| 99 | if (ctrl->value < qctrl->minimum || ctrl->value > qctrl->maximum) |
| 100 | return -ERANGE; |
| 101 | if (qctrl->type == V4L2_CTRL_TYPE_MENU && menu_items != NULL) { |
| 102 | if (menu_items[ctrl->value] == NULL || |
| 103 | menu_items[ctrl->value][0] == '\0') |
| 104 | return -EINVAL; |
| 105 | } |
| 106 | if (qctrl->type == V4L2_CTRL_TYPE_BITMASK && |
| 107 | (ctrl->value & ~qctrl->maximum)) |
| 108 | return -ERANGE; |
| 109 | return 0; |
| 110 | } |
| 111 | EXPORT_SYMBOL(v4l2_ctrl_check); |
| 112 | |
| 113 | /* Fill in a struct v4l2_queryctrl */ |
| 114 | int v4l2_ctrl_query_fill(struct v4l2_queryctrl *qctrl, s32 _min, s32 _max, s32 _step, s32 _def) |
| 115 | { |
| 116 | const char *name; |
| 117 | s64 min = _min; |
| 118 | s64 max = _max; |
| 119 | u64 step = _step; |
| 120 | s64 def = _def; |
| 121 | |
| 122 | v4l2_ctrl_fill(qctrl->id, &name, &qctrl->type, |
| 123 | &min, &max, &step, &def, &qctrl->flags); |
| 124 | |
| 125 | if (name == NULL) |
| 126 | return -EINVAL; |
| 127 | |
| 128 | qctrl->minimum = min; |
| 129 | qctrl->maximum = max; |
| 130 | qctrl->step = step; |
| 131 | qctrl->default_value = def; |
| 132 | qctrl->reserved[0] = qctrl->reserved[1] = 0; |
| 133 | strlcpy(qctrl->name, name, sizeof(qctrl->name)); |
| 134 | return 0; |
| 135 | } |
| 136 | EXPORT_SYMBOL(v4l2_ctrl_query_fill); |
| 137 | |
| 138 | /* Fill in a struct v4l2_querymenu based on the struct v4l2_queryctrl and |
| 139 | the menu. The qctrl pointer may be NULL, in which case it is ignored. |
| 140 | If menu_items is NULL, then the menu items are retrieved using |
| 141 | v4l2_ctrl_get_menu. */ |
| 142 | int v4l2_ctrl_query_menu(struct v4l2_querymenu *qmenu, struct v4l2_queryctrl *qctrl, |
| 143 | const char * const *menu_items) |
| 144 | { |
| 145 | int i; |
| 146 | |
| 147 | qmenu->reserved = 0; |
| 148 | if (menu_items == NULL) |
| 149 | menu_items = v4l2_ctrl_get_menu(qmenu->id); |
| 150 | if (menu_items == NULL || |
| 151 | (qctrl && (qmenu->index < qctrl->minimum || qmenu->index > qctrl->maximum))) |
| 152 | return -EINVAL; |
| 153 | for (i = 0; i < qmenu->index && menu_items[i]; i++) ; |
| 154 | if (menu_items[i] == NULL || menu_items[i][0] == '\0') |
| 155 | return -EINVAL; |
| 156 | strlcpy(qmenu->name, menu_items[qmenu->index], sizeof(qmenu->name)); |
| 157 | return 0; |
| 158 | } |
| 159 | EXPORT_SYMBOL(v4l2_ctrl_query_menu); |
| 160 | |
| 161 | /* Fill in a struct v4l2_querymenu based on the specified array of valid |
| 162 | menu items (terminated by V4L2_CTRL_MENU_IDS_END). |
| 163 | Use this if there are 'holes' in the list of valid menu items. */ |
| 164 | int v4l2_ctrl_query_menu_valid_items(struct v4l2_querymenu *qmenu, const u32 *ids) |
| 165 | { |
| 166 | const char * const *menu_items = v4l2_ctrl_get_menu(qmenu->id); |
| 167 | |
| 168 | qmenu->reserved = 0; |
| 169 | if (menu_items == NULL || ids == NULL) |
| 170 | return -EINVAL; |
| 171 | while (*ids != V4L2_CTRL_MENU_IDS_END) { |
| 172 | if (*ids++ == qmenu->index) { |
| 173 | strlcpy(qmenu->name, menu_items[qmenu->index], |
| 174 | sizeof(qmenu->name)); |
| 175 | return 0; |
| 176 | } |
| 177 | } |
| 178 | return -EINVAL; |
| 179 | } |
| 180 | EXPORT_SYMBOL(v4l2_ctrl_query_menu_valid_items); |
| 181 | |
| 182 | /* ctrl_classes points to an array of u32 pointers, the last element is |
| 183 | a NULL pointer. Each u32 array is a 0-terminated array of control IDs. |
| 184 | Each array must be sorted low to high and belong to the same control |
| 185 | class. The array of u32 pointers must also be sorted, from low class IDs |
| 186 | to high class IDs. |
| 187 | |
| 188 | This function returns the first ID that follows after the given ID. |
| 189 | When no more controls are available 0 is returned. */ |
| 190 | u32 v4l2_ctrl_next(const u32 * const * ctrl_classes, u32 id) |
| 191 | { |
| 192 | u32 ctrl_class = V4L2_CTRL_ID2CLASS(id); |
| 193 | const u32 *pctrl; |
| 194 | |
| 195 | if (ctrl_classes == NULL) |
| 196 | return 0; |
| 197 | |
| 198 | /* if no query is desired, then check if the ID is part of ctrl_classes */ |
| 199 | if ((id & V4L2_CTRL_FLAG_NEXT_CTRL) == 0) { |
| 200 | /* find class */ |
| 201 | while (*ctrl_classes && V4L2_CTRL_ID2CLASS(**ctrl_classes) != ctrl_class) |
| 202 | ctrl_classes++; |
| 203 | if (*ctrl_classes == NULL) |
| 204 | return 0; |
| 205 | pctrl = *ctrl_classes; |
| 206 | /* find control ID */ |
| 207 | while (*pctrl && *pctrl != id) pctrl++; |
| 208 | return *pctrl ? id : 0; |
| 209 | } |
| 210 | id &= V4L2_CTRL_ID_MASK; |
| 211 | id++; /* select next control */ |
| 212 | /* find first class that matches (or is greater than) the class of |
| 213 | the ID */ |
| 214 | while (*ctrl_classes && V4L2_CTRL_ID2CLASS(**ctrl_classes) < ctrl_class) |
| 215 | ctrl_classes++; |
| 216 | /* no more classes */ |
| 217 | if (*ctrl_classes == NULL) |
| 218 | return 0; |
| 219 | pctrl = *ctrl_classes; |
| 220 | /* find first ctrl within the class that is >= ID */ |
| 221 | while (*pctrl && *pctrl < id) pctrl++; |
| 222 | if (*pctrl) |
| 223 | return *pctrl; |
| 224 | /* we are at the end of the controls of the current class. */ |
| 225 | /* continue with next class if available */ |
| 226 | ctrl_classes++; |
| 227 | if (*ctrl_classes == NULL) |
| 228 | return 0; |
| 229 | return **ctrl_classes; |
| 230 | } |
| 231 | EXPORT_SYMBOL(v4l2_ctrl_next); |
| 232 | |
| 233 | /* I2C Helper functions */ |
| 234 | |
| 235 | #if IS_ENABLED(CONFIG_I2C) |
| 236 | |
| 237 | void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client, |
| 238 | const struct v4l2_subdev_ops *ops) |
| 239 | { |
| 240 | v4l2_subdev_init(sd, ops); |
| 241 | sd->flags |= V4L2_SUBDEV_FL_IS_I2C; |
| 242 | /* the owner is the same as the i2c_client's driver owner */ |
| 243 | sd->owner = client->dev.driver->owner; |
| 244 | sd->dev = &client->dev; |
| 245 | /* i2c_client and v4l2_subdev point to one another */ |
| 246 | v4l2_set_subdevdata(sd, client); |
| 247 | i2c_set_clientdata(client, sd); |
| 248 | /* initialize name */ |
| 249 | snprintf(sd->name, sizeof(sd->name), "%s %d-%04x", |
| 250 | client->dev.driver->name, i2c_adapter_id(client->adapter), |
| 251 | client->addr); |
| 252 | } |
| 253 | EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init); |
| 254 | |
| 255 | /* Load an i2c sub-device. */ |
| 256 | struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev, |
| 257 | struct i2c_adapter *adapter, struct i2c_board_info *info, |
| 258 | const unsigned short *probe_addrs) |
| 259 | { |
| 260 | struct v4l2_subdev *sd = NULL; |
| 261 | struct i2c_client *client; |
| 262 | |
| 263 | BUG_ON(!v4l2_dev); |
| 264 | |
| 265 | request_module(I2C_MODULE_PREFIX "%s", info->type); |
| 266 | |
| 267 | /* Create the i2c client */ |
| 268 | if (info->addr == 0 && probe_addrs) |
| 269 | client = i2c_new_probed_device(adapter, info, probe_addrs, |
| 270 | NULL); |
| 271 | else |
| 272 | client = i2c_new_device(adapter, info); |
| 273 | |
| 274 | /* Note: by loading the module first we are certain that c->driver |
| 275 | will be set if the driver was found. If the module was not loaded |
| 276 | first, then the i2c core tries to delay-load the module for us, |
| 277 | and then c->driver is still NULL until the module is finally |
| 278 | loaded. This delay-load mechanism doesn't work if other drivers |
| 279 | want to use the i2c device, so explicitly loading the module |
| 280 | is the best alternative. */ |
| 281 | if (client == NULL || client->dev.driver == NULL) |
| 282 | goto error; |
| 283 | |
| 284 | /* Lock the module so we can safely get the v4l2_subdev pointer */ |
| 285 | if (!try_module_get(client->dev.driver->owner)) |
| 286 | goto error; |
| 287 | sd = i2c_get_clientdata(client); |
| 288 | |
| 289 | /* Register with the v4l2_device which increases the module's |
| 290 | use count as well. */ |
| 291 | if (v4l2_device_register_subdev(v4l2_dev, sd)) |
| 292 | sd = NULL; |
| 293 | /* Decrease the module use count to match the first try_module_get. */ |
| 294 | module_put(client->dev.driver->owner); |
| 295 | |
| 296 | error: |
| 297 | /* If we have a client but no subdev, then something went wrong and |
| 298 | we must unregister the client. */ |
| 299 | if (client && sd == NULL) |
| 300 | i2c_unregister_device(client); |
| 301 | return sd; |
| 302 | } |
| 303 | EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_board); |
| 304 | |
| 305 | struct v4l2_subdev *v4l2_i2c_new_subdev(struct v4l2_device *v4l2_dev, |
| 306 | struct i2c_adapter *adapter, const char *client_type, |
| 307 | u8 addr, const unsigned short *probe_addrs) |
| 308 | { |
| 309 | struct i2c_board_info info; |
| 310 | |
| 311 | /* Setup the i2c board info with the device type and |
| 312 | the device address. */ |
| 313 | memset(&info, 0, sizeof(info)); |
| 314 | strlcpy(info.type, client_type, sizeof(info.type)); |
| 315 | info.addr = addr; |
| 316 | |
| 317 | return v4l2_i2c_new_subdev_board(v4l2_dev, adapter, &info, probe_addrs); |
| 318 | } |
| 319 | EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev); |
| 320 | |
| 321 | /* Return i2c client address of v4l2_subdev. */ |
| 322 | unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd) |
| 323 | { |
| 324 | struct i2c_client *client = v4l2_get_subdevdata(sd); |
| 325 | |
| 326 | return client ? client->addr : I2C_CLIENT_END; |
| 327 | } |
| 328 | EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_addr); |
| 329 | |
| 330 | /* Return a list of I2C tuner addresses to probe. Use only if the tuner |
| 331 | addresses are unknown. */ |
| 332 | const unsigned short *v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type) |
| 333 | { |
| 334 | static const unsigned short radio_addrs[] = { |
| 335 | #if IS_ENABLED(CONFIG_MEDIA_TUNER_TEA5761) |
| 336 | 0x10, |
| 337 | #endif |
| 338 | 0x60, |
| 339 | I2C_CLIENT_END |
| 340 | }; |
| 341 | static const unsigned short demod_addrs[] = { |
| 342 | 0x42, 0x43, 0x4a, 0x4b, |
| 343 | I2C_CLIENT_END |
| 344 | }; |
| 345 | static const unsigned short tv_addrs[] = { |
| 346 | 0x42, 0x43, 0x4a, 0x4b, /* tda8290 */ |
| 347 | 0x60, 0x61, 0x62, 0x63, 0x64, |
| 348 | I2C_CLIENT_END |
| 349 | }; |
| 350 | |
| 351 | switch (type) { |
| 352 | case ADDRS_RADIO: |
| 353 | return radio_addrs; |
| 354 | case ADDRS_DEMOD: |
| 355 | return demod_addrs; |
| 356 | case ADDRS_TV: |
| 357 | return tv_addrs; |
| 358 | case ADDRS_TV_WITH_DEMOD: |
| 359 | return tv_addrs + 4; |
| 360 | } |
| 361 | return NULL; |
| 362 | } |
| 363 | EXPORT_SYMBOL_GPL(v4l2_i2c_tuner_addrs); |
| 364 | |
| 365 | #endif /* defined(CONFIG_I2C) */ |
| 366 | |
| 367 | #if defined(CONFIG_SPI) |
| 368 | |
| 369 | /* Load an spi sub-device. */ |
| 370 | |
| 371 | void v4l2_spi_subdev_init(struct v4l2_subdev *sd, struct spi_device *spi, |
| 372 | const struct v4l2_subdev_ops *ops) |
| 373 | { |
| 374 | v4l2_subdev_init(sd, ops); |
| 375 | sd->flags |= V4L2_SUBDEV_FL_IS_SPI; |
| 376 | /* the owner is the same as the spi_device's driver owner */ |
| 377 | sd->owner = spi->dev.driver->owner; |
| 378 | sd->dev = &spi->dev; |
| 379 | /* spi_device and v4l2_subdev point to one another */ |
| 380 | v4l2_set_subdevdata(sd, spi); |
| 381 | spi_set_drvdata(spi, sd); |
| 382 | /* initialize name */ |
| 383 | strlcpy(sd->name, spi->dev.driver->name, sizeof(sd->name)); |
| 384 | } |
| 385 | EXPORT_SYMBOL_GPL(v4l2_spi_subdev_init); |
| 386 | |
| 387 | struct v4l2_subdev *v4l2_spi_new_subdev(struct v4l2_device *v4l2_dev, |
| 388 | struct spi_master *master, struct spi_board_info *info) |
| 389 | { |
| 390 | struct v4l2_subdev *sd = NULL; |
| 391 | struct spi_device *spi = NULL; |
| 392 | |
| 393 | BUG_ON(!v4l2_dev); |
| 394 | |
| 395 | if (info->modalias[0]) |
| 396 | request_module(info->modalias); |
| 397 | |
| 398 | spi = spi_new_device(master, info); |
| 399 | |
| 400 | if (spi == NULL || spi->dev.driver == NULL) |
| 401 | goto error; |
| 402 | |
| 403 | if (!try_module_get(spi->dev.driver->owner)) |
| 404 | goto error; |
| 405 | |
| 406 | sd = spi_get_drvdata(spi); |
| 407 | |
| 408 | /* Register with the v4l2_device which increases the module's |
| 409 | use count as well. */ |
| 410 | if (v4l2_device_register_subdev(v4l2_dev, sd)) |
| 411 | sd = NULL; |
| 412 | |
| 413 | /* Decrease the module use count to match the first try_module_get. */ |
| 414 | module_put(spi->dev.driver->owner); |
| 415 | |
| 416 | error: |
| 417 | /* If we have a client but no subdev, then something went wrong and |
| 418 | we must unregister the client. */ |
| 419 | if (spi && sd == NULL) |
| 420 | spi_unregister_device(spi); |
| 421 | |
| 422 | return sd; |
| 423 | } |
| 424 | EXPORT_SYMBOL_GPL(v4l2_spi_new_subdev); |
| 425 | |
| 426 | #endif /* defined(CONFIG_SPI) */ |
| 427 | |
| 428 | /* Clamp x to be between min and max, aligned to a multiple of 2^align. min |
| 429 | * and max don't have to be aligned, but there must be at least one valid |
| 430 | * value. E.g., min=17,max=31,align=4 is not allowed as there are no multiples |
| 431 | * of 16 between 17 and 31. */ |
| 432 | static unsigned int clamp_align(unsigned int x, unsigned int min, |
| 433 | unsigned int max, unsigned int align) |
| 434 | { |
| 435 | /* Bits that must be zero to be aligned */ |
| 436 | unsigned int mask = ~((1 << align) - 1); |
| 437 | |
| 438 | /* Round to nearest aligned value */ |
| 439 | if (align) |
| 440 | x = (x + (1 << (align - 1))) & mask; |
| 441 | |
| 442 | /* Clamp to aligned value of min and max */ |
| 443 | if (x < min) |
| 444 | x = (min + ~mask) & mask; |
| 445 | else if (x > max) |
| 446 | x = max & mask; |
| 447 | |
| 448 | return x; |
| 449 | } |
| 450 | |
| 451 | /* Bound an image to have a width between wmin and wmax, and height between |
| 452 | * hmin and hmax, inclusive. Additionally, the width will be a multiple of |
| 453 | * 2^walign, the height will be a multiple of 2^halign, and the overall size |
| 454 | * (width*height) will be a multiple of 2^salign. The image may be shrunk |
| 455 | * or enlarged to fit the alignment constraints. |
| 456 | * |
| 457 | * The width or height maximum must not be smaller than the corresponding |
| 458 | * minimum. The alignments must not be so high there are no possible image |
| 459 | * sizes within the allowed bounds. wmin and hmin must be at least 1 |
| 460 | * (don't use 0). If you don't care about a certain alignment, specify 0, |
| 461 | * as 2^0 is 1 and one byte alignment is equivalent to no alignment. If |
| 462 | * you only want to adjust downward, specify a maximum that's the same as |
| 463 | * the initial value. |
| 464 | */ |
| 465 | void v4l_bound_align_image(u32 *w, unsigned int wmin, unsigned int wmax, |
| 466 | unsigned int walign, |
| 467 | u32 *h, unsigned int hmin, unsigned int hmax, |
| 468 | unsigned int halign, unsigned int salign) |
| 469 | { |
| 470 | *w = clamp_align(*w, wmin, wmax, walign); |
| 471 | *h = clamp_align(*h, hmin, hmax, halign); |
| 472 | |
| 473 | /* Usually we don't need to align the size and are done now. */ |
| 474 | if (!salign) |
| 475 | return; |
| 476 | |
| 477 | /* How much alignment do we have? */ |
| 478 | walign = __ffs(*w); |
| 479 | halign = __ffs(*h); |
| 480 | /* Enough to satisfy the image alignment? */ |
| 481 | if (walign + halign < salign) { |
| 482 | /* Max walign where there is still a valid width */ |
| 483 | unsigned int wmaxa = __fls(wmax ^ (wmin - 1)); |
| 484 | /* Max halign where there is still a valid height */ |
| 485 | unsigned int hmaxa = __fls(hmax ^ (hmin - 1)); |
| 486 | |
| 487 | /* up the smaller alignment until we have enough */ |
| 488 | do { |
| 489 | if (halign >= hmaxa || |
| 490 | (walign <= halign && walign < wmaxa)) { |
| 491 | *w = clamp_align(*w, wmin, wmax, walign + 1); |
| 492 | walign = __ffs(*w); |
| 493 | } else { |
| 494 | *h = clamp_align(*h, hmin, hmax, halign + 1); |
| 495 | halign = __ffs(*h); |
| 496 | } |
| 497 | } while (halign + walign < salign); |
| 498 | } |
| 499 | } |
| 500 | EXPORT_SYMBOL_GPL(v4l_bound_align_image); |
| 501 | |
| 502 | const struct v4l2_frmsize_discrete *v4l2_find_nearest_format( |
| 503 | const struct v4l2_discrete_probe *probe, |
| 504 | s32 width, s32 height) |
| 505 | { |
| 506 | int i; |
| 507 | u32 error, min_error = UINT_MAX; |
| 508 | const struct v4l2_frmsize_discrete *size, *best = NULL; |
| 509 | |
| 510 | if (!probe) |
| 511 | return best; |
| 512 | |
| 513 | for (i = 0, size = probe->sizes; i < probe->num_sizes; i++, size++) { |
| 514 | error = abs(size->width - width) + abs(size->height - height); |
| 515 | if (error < min_error) { |
| 516 | min_error = error; |
| 517 | best = size; |
| 518 | } |
| 519 | if (!error) |
| 520 | break; |
| 521 | } |
| 522 | |
| 523 | return best; |
| 524 | } |
| 525 | EXPORT_SYMBOL_GPL(v4l2_find_nearest_format); |
| 526 | |
| 527 | void v4l2_get_timestamp(struct timeval *tv) |
| 528 | { |
| 529 | struct timespec ts; |
| 530 | |
| 531 | ktime_get_ts(&ts); |
| 532 | tv->tv_sec = ts.tv_sec; |
| 533 | tv->tv_usec = ts.tv_nsec / NSEC_PER_USEC; |
| 534 | } |
| 535 | EXPORT_SYMBOL_GPL(v4l2_get_timestamp); |