/* * Video for Linux Two * * A generic video device interface for the LINUX operating system * using a set of device structures/vectors for low level operations. * * This file replaces the videodev.c file that comes with the * regular kernel distribution. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Author: Bill Dirks * based on code by Alan Cox, * */ /* * Video capture interface for Linux * * A generic video device interface for the LINUX operating system * using a set of device structures/vectors for low level operations. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Author: Alan Cox, * * Fixes: */ /* * Video4linux 1/2 integration by Justin Schoeman * * 2.4 PROCFS support ported from 2.4 kernels by * Iñaki García Etxebarria * Makefile fix by "W. Michael Petullo" * 2.4 devfs support ported from 2.4 kernels by * Dan Merillat * Added Gerd Knorrs v4l1 enhancements (Justin Schoeman) */ #include #include #include #include #include #include #include #if defined(CONFIG_SPI) #include #endif #include #include #include #include #include #include #include #include MODULE_AUTHOR("Bill Dirks, Justin Schoeman, Gerd Knorr"); MODULE_DESCRIPTION("misc helper functions for v4l2 device drivers"); MODULE_LICENSE("GPL"); /* * * V 4 L 2 D R I V E R H E L P E R A P I * */ /* * Video Standard Operations (contributed by Michael Schimek) */ /* Helper functions for control handling */ /* Fill in a struct v4l2_queryctrl */ int v4l2_ctrl_query_fill(struct v4l2_queryctrl *qctrl, s32 _min, s32 _max, s32 _step, s32 _def) { const char *name; s64 min = _min; s64 max = _max; u64 step = _step; s64 def = _def; v4l2_ctrl_fill(qctrl->id, &name, &qctrl->type, &min, &max, &step, &def, &qctrl->flags); if (name == NULL) return -EINVAL; qctrl->minimum = min; qctrl->maximum = max; qctrl->step = step; qctrl->default_value = def; qctrl->reserved[0] = qctrl->reserved[1] = 0; strlcpy(qctrl->name, name, sizeof(qctrl->name)); return 0; } EXPORT_SYMBOL(v4l2_ctrl_query_fill); /* I2C Helper functions */ #if IS_ENABLED(CONFIG_I2C) void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client, const struct v4l2_subdev_ops *ops) { v4l2_subdev_init(sd, ops); sd->flags |= V4L2_SUBDEV_FL_IS_I2C; /* the owner is the same as the i2c_client's driver owner */ sd->owner = client->dev.driver->owner; sd->dev = &client->dev; /* i2c_client and v4l2_subdev point to one another */ v4l2_set_subdevdata(sd, client); i2c_set_clientdata(client, sd); /* initialize name */ snprintf(sd->name, sizeof(sd->name), "%s %d-%04x", client->dev.driver->name, i2c_adapter_id(client->adapter), client->addr); } EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_init); /* Load an i2c sub-device. */ struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev, struct i2c_adapter *adapter, struct i2c_board_info *info, const unsigned short *probe_addrs) { struct v4l2_subdev *sd = NULL; struct i2c_client *client; BUG_ON(!v4l2_dev); request_module(I2C_MODULE_PREFIX "%s", info->type); /* Create the i2c client */ if (info->addr == 0 && probe_addrs) client = i2c_new_probed_device(adapter, info, probe_addrs, NULL); else client = i2c_new_device(adapter, info); /* Note: by loading the module first we are certain that c->driver will be set if the driver was found. If the module was not loaded first, then the i2c core tries to delay-load the module for us, and then c->driver is still NULL until the module is finally loaded. This delay-load mechanism doesn't work if other drivers want to use the i2c device, so explicitly loading the module is the best alternative. */ if (client == NULL || client->dev.driver == NULL) goto error; /* Lock the module so we can safely get the v4l2_subdev pointer */ if (!try_module_get(client->dev.driver->owner)) goto error; sd = i2c_get_clientdata(client); /* Register with the v4l2_device which increases the module's use count as well. */ if (v4l2_device_register_subdev(v4l2_dev, sd)) sd = NULL; /* Decrease the module use count to match the first try_module_get. */ module_put(client->dev.driver->owner); error: /* If we have a client but no subdev, then something went wrong and we must unregister the client. */ if (client && sd == NULL) i2c_unregister_device(client); return sd; } EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_board); struct v4l2_subdev *v4l2_i2c_new_subdev(struct v4l2_device *v4l2_dev, struct i2c_adapter *adapter, const char *client_type, u8 addr, const unsigned short *probe_addrs) { struct i2c_board_info info; /* Setup the i2c board info with the device type and the device address. */ memset(&info, 0, sizeof(info)); strlcpy(info.type, client_type, sizeof(info.type)); info.addr = addr; return v4l2_i2c_new_subdev_board(v4l2_dev, adapter, &info, probe_addrs); } EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev); /* Return i2c client address of v4l2_subdev. */ unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd) { struct i2c_client *client = v4l2_get_subdevdata(sd); return client ? client->addr : I2C_CLIENT_END; } EXPORT_SYMBOL_GPL(v4l2_i2c_subdev_addr); /* Return a list of I2C tuner addresses to probe. Use only if the tuner addresses are unknown. */ const unsigned short *v4l2_i2c_tuner_addrs(enum v4l2_i2c_tuner_type type) { static const unsigned short radio_addrs[] = { #if IS_ENABLED(CONFIG_MEDIA_TUNER_TEA5761) 0x10, #endif 0x60, I2C_CLIENT_END }; static const unsigned short demod_addrs[] = { 0x42, 0x43, 0x4a, 0x4b, I2C_CLIENT_END }; static const unsigned short tv_addrs[] = { 0x42, 0x43, 0x4a, 0x4b, /* tda8290 */ 0x60, 0x61, 0x62, 0x63, 0x64, I2C_CLIENT_END }; switch (type) { case ADDRS_RADIO: return radio_addrs; case ADDRS_DEMOD: return demod_addrs; case ADDRS_TV: return tv_addrs; case ADDRS_TV_WITH_DEMOD: return tv_addrs + 4; } return NULL; } EXPORT_SYMBOL_GPL(v4l2_i2c_tuner_addrs); #endif /* defined(CONFIG_I2C) */ #if defined(CONFIG_SPI) /* Load an spi sub-device. */ void v4l2_spi_subdev_init(struct v4l2_subdev *sd, struct spi_device *spi, const struct v4l2_subdev_ops *ops) { v4l2_subdev_init(sd, ops); sd->flags |= V4L2_SUBDEV_FL_IS_SPI; /* the owner is the same as the spi_device's driver owner */ sd->owner = spi->dev.driver->owner; sd->dev = &spi->dev; /* spi_device and v4l2_subdev point to one another */ v4l2_set_subdevdata(sd, spi); spi_set_drvdata(spi, sd); /* initialize name */ strlcpy(sd->name, spi->dev.driver->name, sizeof(sd->name)); } EXPORT_SYMBOL_GPL(v4l2_spi_subdev_init); struct v4l2_subdev *v4l2_spi_new_subdev(struct v4l2_device *v4l2_dev, struct spi_master *master, struct spi_board_info *info) { struct v4l2_subdev *sd = NULL; struct spi_device *spi = NULL; BUG_ON(!v4l2_dev); if (info->modalias[0]) request_module(info->modalias); spi = spi_new_device(master, info); if (spi == NULL || spi->dev.driver == NULL) goto error; if (!try_module_get(spi->dev.driver->owner)) goto error; sd = spi_get_drvdata(spi); /* Register with the v4l2_device which increases the module's use count as well. */ if (v4l2_device_register_subdev(v4l2_dev, sd)) sd = NULL; /* Decrease the module use count to match the first try_module_get. */ module_put(spi->dev.driver->owner); error: /* If we have a client but no subdev, then something went wrong and we must unregister the client. */ if (!sd) spi_unregister_device(spi); return sd; } EXPORT_SYMBOL_GPL(v4l2_spi_new_subdev); #endif /* defined(CONFIG_SPI) */ /* Clamp x to be between min and max, aligned to a multiple of 2^align. min * and max don't have to be aligned, but there must be at least one valid * value. E.g., min=17,max=31,align=4 is not allowed as there are no multiples * of 16 between 17 and 31. */ static unsigned int clamp_align(unsigned int x, unsigned int min, unsigned int max, unsigned int align) { /* Bits that must be zero to be aligned */ unsigned int mask = ~((1 << align) - 1); /* Clamp to aligned min and max */ x = clamp(x, (min + ~mask) & mask, max & mask); /* Round to nearest aligned value */ if (align) x = (x + (1 << (align - 1))) & mask; return x; } void v4l_bound_align_image(u32 *w, unsigned int wmin, unsigned int wmax, unsigned int walign, u32 *h, unsigned int hmin, unsigned int hmax, unsigned int halign, unsigned int salign) { *w = clamp_align(*w, wmin, wmax, walign); *h = clamp_align(*h, hmin, hmax, halign); /* Usually we don't need to align the size and are done now. */ if (!salign) return; /* How much alignment do we have? */ walign = __ffs(*w); halign = __ffs(*h); /* Enough to satisfy the image alignment? */ if (walign + halign < salign) { /* Max walign where there is still a valid width */ unsigned int wmaxa = __fls(wmax ^ (wmin - 1)); /* Max halign where there is still a valid height */ unsigned int hmaxa = __fls(hmax ^ (hmin - 1)); /* up the smaller alignment until we have enough */ do { if (halign >= hmaxa || (walign <= halign && walign < wmaxa)) { *w = clamp_align(*w, wmin, wmax, walign + 1); walign = __ffs(*w); } else { *h = clamp_align(*h, hmin, hmax, halign + 1); halign = __ffs(*h); } } while (halign + walign < salign); } } EXPORT_SYMBOL_GPL(v4l_bound_align_image); const struct v4l2_frmsize_discrete * v4l2_find_nearest_format(const struct v4l2_frmsize_discrete *sizes, size_t num_sizes, s32 width, s32 height) { int i; u32 error, min_error = UINT_MAX; const struct v4l2_frmsize_discrete *size, *best = NULL; if (!sizes) return NULL; for (i = 0, size = sizes; i < num_sizes; i++, size++) { error = abs(size->width - width) + abs(size->height - height); if (error < min_error) { min_error = error; best = size; } if (!error) break; } return best; } EXPORT_SYMBOL_GPL(v4l2_find_nearest_format); void v4l2_get_timestamp(struct timeval *tv) { struct timespec ts; ktime_get_ts(&ts); tv->tv_sec = ts.tv_sec; tv->tv_usec = ts.tv_nsec / NSEC_PER_USEC; } EXPORT_SYMBOL_GPL(v4l2_get_timestamp);