s390/ptrace: get rid of long longs in psw_bits
[linux/fpc-iii.git] / drivers / media / v4l2-core / v4l2-common.c
blob5b808500e7e79166c4c2868a8c37d737209eb263
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/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>
65 #include <linux/videodev2.h>
67 MODULE_AUTHOR("Bill Dirks, Justin Schoeman, Gerd Knorr");
68 MODULE_DESCRIPTION("misc helper functions for v4l2 device drivers");
69 MODULE_LICENSE("GPL");
73 * V 4 L 2 D R I V E R H E L P E R A P I
78 * Video Standard Operations (contributed by Michael Schimek)
81 /* Helper functions for control handling */
83 /* Fill in a struct v4l2_queryctrl */
84 int v4l2_ctrl_query_fill(struct v4l2_queryctrl *qctrl, s32 _min, s32 _max, s32 _step, s32 _def)
86 const char *name;
87 s64 min = _min;
88 s64 max = _max;
89 u64 step = _step;
90 s64 def = _def;
92 v4l2_ctrl_fill(qctrl->id, &name, &qctrl->type,
93 &min, &max, &step, &def, &qctrl->flags);
95 if (name == NULL)
96 return -EINVAL;
98 qctrl->minimum = min;
99 qctrl->maximum = max;
100 qctrl->step = step;
101 qctrl->default_value = def;
102 qctrl->reserved[0] = qctrl->reserved[1] = 0;
103 strlcpy(qctrl->name, name, sizeof(qctrl->name));
104 return 0;
106 EXPORT_SYMBOL(v4l2_ctrl_query_fill);
108 /* I2C Helper functions */
110 #if IS_ENABLED(CONFIG_I2C)
112 void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client,
113 const struct v4l2_subdev_ops *ops)
115 v4l2_subdev_init(sd, ops);
116 sd->flags |= V4L2_SUBDEV_FL_IS_I2C;
117 /* the owner is the same as the i2c_client's driver owner */
118 sd->owner = client->dev.driver->owner;
119 sd->dev = &client->dev;
120 /* i2c_client and v4l2_subdev point to one another */
121 v4l2_set_subdevdata(sd, client);
122 i2c_set_clientdata(client, sd);
123 /* initialize name */
124 snprintf(sd->name, sizeof(sd->name), "%s %d-%04x",
125 client->dev.driver->name, i2c_adapter_id(client->adapter),
126 client->addr);
128 EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init);
130 /* Load an i2c sub-device. */
131 struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev,
132 struct i2c_adapter *adapter, struct i2c_board_info *info,
133 const unsigned short *probe_addrs)
135 struct v4l2_subdev *sd = NULL;
136 struct i2c_client *client;
138 BUG_ON(!v4l2_dev);
140 request_module(I2C_MODULE_PREFIX "%s", info->type);
142 /* Create the i2c client */
143 if (info->addr == 0 && probe_addrs)
144 client = i2c_new_probed_device(adapter, info, probe_addrs,
145 NULL);
146 else
147 client = i2c_new_device(adapter, info);
149 /* Note: by loading the module first we are certain that c->driver
150 will be set if the driver was found. If the module was not loaded
151 first, then the i2c core tries to delay-load the module for us,
152 and then c->driver is still NULL until the module is finally
153 loaded. This delay-load mechanism doesn't work if other drivers
154 want to use the i2c device, so explicitly loading the module
155 is the best alternative. */
156 if (client == NULL || client->dev.driver == NULL)
157 goto error;
159 /* Lock the module so we can safely get the v4l2_subdev pointer */
160 if (!try_module_get(client->dev.driver->owner))
161 goto error;
162 sd = i2c_get_clientdata(client);
164 /* Register with the v4l2_device which increases the module's
165 use count as well. */
166 if (v4l2_device_register_subdev(v4l2_dev, sd))
167 sd = NULL;
168 /* Decrease the module use count to match the first try_module_get. */
169 module_put(client->dev.driver->owner);
171 error:
172 /* If we have a client but no subdev, then something went wrong and
173 we must unregister the client. */
174 if (client && sd == NULL)
175 i2c_unregister_device(client);
176 return sd;
178 EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_board);
180 struct v4l2_subdev *v4l2_i2c_new_subdev(struct v4l2_device *v4l2_dev,
181 struct i2c_adapter *adapter, const char *client_type,
182 u8 addr, const unsigned short *probe_addrs)
184 struct i2c_board_info info;
186 /* Setup the i2c board info with the device type and
187 the device address. */
188 memset(&info, 0, sizeof(info));
189 strlcpy(info.type, client_type, sizeof(info.type));
190 info.addr = addr;
192 return v4l2_i2c_new_subdev_board(v4l2_dev, adapter, &info, probe_addrs);
194 EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev);
196 /* Return i2c client address of v4l2_subdev. */
197 unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd)
199 struct i2c_client *client = v4l2_get_subdevdata(sd);
201 return client ? client->addr : I2C_CLIENT_END;
203 EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_addr);
205 /* Return a list of I2C tuner addresses to probe. Use only if the tuner
206 addresses are unknown. */
207 const unsigned short *v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type)
209 static const unsigned short radio_addrs[] = {
210 #if IS_ENABLED(CONFIG_MEDIA_TUNER_TEA5761)
211 0x10,
212 #endif
213 0x60,
214 I2C_CLIENT_END
216 static const unsigned short demod_addrs[] = {
217 0x42, 0x43, 0x4a, 0x4b,
218 I2C_CLIENT_END
220 static const unsigned short tv_addrs[] = {
221 0x42, 0x43, 0x4a, 0x4b, /* tda8290 */
222 0x60, 0x61, 0x62, 0x63, 0x64,
223 I2C_CLIENT_END
226 switch (type) {
227 case ADDRS_RADIO:
228 return radio_addrs;
229 case ADDRS_DEMOD:
230 return demod_addrs;
231 case ADDRS_TV:
232 return tv_addrs;
233 case ADDRS_TV_WITH_DEMOD:
234 return tv_addrs + 4;
236 return NULL;
238 EXPORT_SYMBOL_GPL(v4l2_i2c_tuner_addrs);
240 #endif /* defined(CONFIG_I2C) */
242 #if defined(CONFIG_SPI)
244 /* Load an spi sub-device. */
246 void v4l2_spi_subdev_init(struct v4l2_subdev *sd, struct spi_device *spi,
247 const struct v4l2_subdev_ops *ops)
249 v4l2_subdev_init(sd, ops);
250 sd->flags |= V4L2_SUBDEV_FL_IS_SPI;
251 /* the owner is the same as the spi_device's driver owner */
252 sd->owner = spi->dev.driver->owner;
253 sd->dev = &spi->dev;
254 /* spi_device and v4l2_subdev point to one another */
255 v4l2_set_subdevdata(sd, spi);
256 spi_set_drvdata(spi, sd);
257 /* initialize name */
258 strlcpy(sd->name, spi->dev.driver->name, sizeof(sd->name));
260 EXPORT_SYMBOL_GPL(v4l2_spi_subdev_init);
262 struct v4l2_subdev *v4l2_spi_new_subdev(struct v4l2_device *v4l2_dev,
263 struct spi_master *master, struct spi_board_info *info)
265 struct v4l2_subdev *sd = NULL;
266 struct spi_device *spi = NULL;
268 BUG_ON(!v4l2_dev);
270 if (info->modalias[0])
271 request_module(info->modalias);
273 spi = spi_new_device(master, info);
275 if (spi == NULL || spi->dev.driver == NULL)
276 goto error;
278 if (!try_module_get(spi->dev.driver->owner))
279 goto error;
281 sd = spi_get_drvdata(spi);
283 /* Register with the v4l2_device which increases the module's
284 use count as well. */
285 if (v4l2_device_register_subdev(v4l2_dev, sd))
286 sd = NULL;
288 /* Decrease the module use count to match the first try_module_get. */
289 module_put(spi->dev.driver->owner);
291 error:
292 /* If we have a client but no subdev, then something went wrong and
293 we must unregister the client. */
294 if (spi && sd == NULL)
295 spi_unregister_device(spi);
297 return sd;
299 EXPORT_SYMBOL_GPL(v4l2_spi_new_subdev);
301 #endif /* defined(CONFIG_SPI) */
303 /* Clamp x to be between min and max, aligned to a multiple of 2^align. min
304 * and max don't have to be aligned, but there must be at least one valid
305 * value. E.g., min=17,max=31,align=4 is not allowed as there are no multiples
306 * of 16 between 17 and 31. */
307 static unsigned int clamp_align(unsigned int x, unsigned int min,
308 unsigned int max, unsigned int align)
310 /* Bits that must be zero to be aligned */
311 unsigned int mask = ~((1 << align) - 1);
313 /* Clamp to aligned min and max */
314 x = clamp(x, (min + ~mask) & mask, max & mask);
316 /* Round to nearest aligned value */
317 if (align)
318 x = (x + (1 << (align - 1))) & mask;
320 return x;
323 /* Bound an image to have a width between wmin and wmax, and height between
324 * hmin and hmax, inclusive. Additionally, the width will be a multiple of
325 * 2^walign, the height will be a multiple of 2^halign, and the overall size
326 * (width*height) will be a multiple of 2^salign. The image may be shrunk
327 * or enlarged to fit the alignment constraints.
329 * The width or height maximum must not be smaller than the corresponding
330 * minimum. The alignments must not be so high there are no possible image
331 * sizes within the allowed bounds. wmin and hmin must be at least 1
332 * (don't use 0). If you don't care about a certain alignment, specify 0,
333 * as 2^0 is 1 and one byte alignment is equivalent to no alignment. If
334 * you only want to adjust downward, specify a maximum that's the same as
335 * the initial value.
337 void v4l_bound_align_image(u32 *w, unsigned int wmin, unsigned int wmax,
338 unsigned int walign,
339 u32 *h, unsigned int hmin, unsigned int hmax,
340 unsigned int halign, unsigned int salign)
342 *w = clamp_align(*w, wmin, wmax, walign);
343 *h = clamp_align(*h, hmin, hmax, halign);
345 /* Usually we don't need to align the size and are done now. */
346 if (!salign)
347 return;
349 /* How much alignment do we have? */
350 walign = __ffs(*w);
351 halign = __ffs(*h);
352 /* Enough to satisfy the image alignment? */
353 if (walign + halign < salign) {
354 /* Max walign where there is still a valid width */
355 unsigned int wmaxa = __fls(wmax ^ (wmin - 1));
356 /* Max halign where there is still a valid height */
357 unsigned int hmaxa = __fls(hmax ^ (hmin - 1));
359 /* up the smaller alignment until we have enough */
360 do {
361 if (halign >= hmaxa ||
362 (walign <= halign && walign < wmaxa)) {
363 *w = clamp_align(*w, wmin, wmax, walign + 1);
364 walign = __ffs(*w);
365 } else {
366 *h = clamp_align(*h, hmin, hmax, halign + 1);
367 halign = __ffs(*h);
369 } while (halign + walign < salign);
372 EXPORT_SYMBOL_GPL(v4l_bound_align_image);
374 const struct v4l2_frmsize_discrete *v4l2_find_nearest_format(
375 const struct v4l2_discrete_probe *probe,
376 s32 width, s32 height)
378 int i;
379 u32 error, min_error = UINT_MAX;
380 const struct v4l2_frmsize_discrete *size, *best = NULL;
382 if (!probe)
383 return best;
385 for (i = 0, size = probe->sizes; i < probe->num_sizes; i++, size++) {
386 error = abs(size->width - width) + abs(size->height - height);
387 if (error < min_error) {
388 min_error = error;
389 best = size;
391 if (!error)
392 break;
395 return best;
397 EXPORT_SYMBOL_GPL(v4l2_find_nearest_format);
399 void v4l2_get_timestamp(struct timeval *tv)
401 struct timespec ts;
403 ktime_get_ts(&ts);
404 tv->tv_sec = ts.tv_sec;
405 tv->tv_usec = ts.tv_nsec / NSEC_PER_USEC;
407 EXPORT_SYMBOL_GPL(v4l2_get_timestamp);