diff options
Diffstat (limited to 'drivers/media/v4l2-core/v4l2-common.c')
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-common.c | 981 |
1 files changed, 981 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c new file mode 100644 index 000000000000..f995dd31151d --- /dev/null +++ b/drivers/media/v4l2-core/v4l2-common.c @@ -0,0 +1,981 @@ +/* + * 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 <bill@thedirks.org> + * based on code by Alan Cox, <alan@cymru.net> + * + */ + +/* + * 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, <alan@lxorguk.ukuu.org.uk> + * + * Fixes: + */ + +/* + * Video4linux 1/2 integration by Justin Schoeman + * <justin@suntiger.ee.up.ac.za> + * 2.4 PROCFS support ported from 2.4 kernels by + * Iñaki García Etxebarria <garetxe@euskalnet.net> + * Makefile fix by "W. Michael Petullo" <mike@flyn.org> + * 2.4 devfs support ported from 2.4 kernels by + * Dan Merillat <dan@merillat.org> + * Added Gerd Knorrs v4l1 enhancements (Justin Schoeman) + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#if defined(CONFIG_SPI) +#include <linux/spi/spi.h> +#endif +#include <asm/uaccess.h> +#include <asm/pgtable.h> +#include <asm/io.h> +#include <asm/div64.h> +#include <media/v4l2-common.h> +#include <media/v4l2-device.h> +#include <media/v4l2-ctrls.h> +#include <media/v4l2-chip-ident.h> + +#include <linux/videodev2.h> + +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 */ + +/* Check for correctness of the ctrl's value based on the data from + struct v4l2_queryctrl and the available menu items. Note that + menu_items may be NULL, in that case it is ignored. */ +int v4l2_ctrl_check(struct v4l2_ext_control *ctrl, struct v4l2_queryctrl *qctrl, + const char * const *menu_items) +{ + if (qctrl->flags & V4L2_CTRL_FLAG_DISABLED) + return -EINVAL; + if (qctrl->flags & V4L2_CTRL_FLAG_GRABBED) + return -EBUSY; + if (qctrl->type == V4L2_CTRL_TYPE_STRING) + return 0; + if (qctrl->type == V4L2_CTRL_TYPE_BUTTON || + qctrl->type == V4L2_CTRL_TYPE_INTEGER64 || + qctrl->type == V4L2_CTRL_TYPE_CTRL_CLASS) + return 0; + if (ctrl->value < qctrl->minimum || ctrl->value > qctrl->maximum) + return -ERANGE; + if (qctrl->type == V4L2_CTRL_TYPE_MENU && menu_items != NULL) { + if (menu_items[ctrl->value] == NULL || + menu_items[ctrl->value][0] == '\0') + return -EINVAL; + } + if (qctrl->type == V4L2_CTRL_TYPE_BITMASK && + (ctrl->value & ~qctrl->maximum)) + return -ERANGE; + return 0; +} +EXPORT_SYMBOL(v4l2_ctrl_check); + +/* 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; + + 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); + +/* Fill in a struct v4l2_querymenu based on the struct v4l2_queryctrl and + the menu. The qctrl pointer may be NULL, in which case it is ignored. + If menu_items is NULL, then the menu items are retrieved using + v4l2_ctrl_get_menu. */ +int v4l2_ctrl_query_menu(struct v4l2_querymenu *qmenu, struct v4l2_queryctrl *qctrl, + const char * const *menu_items) +{ + int i; + + qmenu->reserved = 0; + if (menu_items == NULL) + menu_items = v4l2_ctrl_get_menu(qmenu->id); + if (menu_items == NULL || + (qctrl && (qmenu->index < qctrl->minimum || qmenu->index > qctrl->maximum))) + return -EINVAL; + for (i = 0; i < qmenu->index && menu_items[i]; i++) ; + if (menu_items[i] == NULL || menu_items[i][0] == '\0') + return -EINVAL; + strlcpy(qmenu->name, menu_items[qmenu->index], sizeof(qmenu->name)); + return 0; +} +EXPORT_SYMBOL(v4l2_ctrl_query_menu); + +/* Fill in a struct v4l2_querymenu based on the specified array of valid + menu items (terminated by V4L2_CTRL_MENU_IDS_END). + Use this if there are 'holes' in the list of valid menu items. */ +int v4l2_ctrl_query_menu_valid_items(struct v4l2_querymenu *qmenu, const u32 *ids) +{ + const char * const *menu_items = v4l2_ctrl_get_menu(qmenu->id); + + qmenu->reserved = 0; + if (menu_items == NULL || ids == NULL) + return -EINVAL; + while (*ids != V4L2_CTRL_MENU_IDS_END) { + if (*ids++ == qmenu->index) { + strlcpy(qmenu->name, menu_items[qmenu->index], + sizeof(qmenu->name)); + return 0; + } + } + return -EINVAL; +} +EXPORT_SYMBOL(v4l2_ctrl_query_menu_valid_items); + +/* ctrl_classes points to an array of u32 pointers, the last element is + a NULL pointer. Each u32 array is a 0-terminated array of control IDs. + Each array must be sorted low to high and belong to the same control + class. The array of u32 pointers must also be sorted, from low class IDs + to high class IDs. + + This function returns the first ID that follows after the given ID. + When no more controls are available 0 is returned. */ +u32 v4l2_ctrl_next(const u32 * const * ctrl_classes, u32 id) +{ + u32 ctrl_class = V4L2_CTRL_ID2CLASS(id); + const u32 *pctrl; + + if (ctrl_classes == NULL) + return 0; + + /* if no query is desired, then check if the ID is part of ctrl_classes */ + if ((id & V4L2_CTRL_FLAG_NEXT_CTRL) == 0) { + /* find class */ + while (*ctrl_classes && V4L2_CTRL_ID2CLASS(**ctrl_classes) != ctrl_class) + ctrl_classes++; + if (*ctrl_classes == NULL) + return 0; + pctrl = *ctrl_classes; + /* find control ID */ + while (*pctrl && *pctrl != id) pctrl++; + return *pctrl ? id : 0; + } + id &= V4L2_CTRL_ID_MASK; + id++; /* select next control */ + /* find first class that matches (or is greater than) the class of + the ID */ + while (*ctrl_classes && V4L2_CTRL_ID2CLASS(**ctrl_classes) < ctrl_class) + ctrl_classes++; + /* no more classes */ + if (*ctrl_classes == NULL) + return 0; + pctrl = *ctrl_classes; + /* find first ctrl within the class that is >= ID */ + while (*pctrl && *pctrl < id) pctrl++; + if (*pctrl) + return *pctrl; + /* we are at the end of the controls of the current class. */ + /* continue with next class if available */ + ctrl_classes++; + if (*ctrl_classes == NULL) + return 0; + return **ctrl_classes; +} +EXPORT_SYMBOL(v4l2_ctrl_next); + +int v4l2_chip_match_host(const struct v4l2_dbg_match *match) +{ + switch (match->type) { + case V4L2_CHIP_MATCH_HOST: + return match->addr == 0; + default: + return 0; + } +} +EXPORT_SYMBOL(v4l2_chip_match_host); + +#if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE)) +int v4l2_chip_match_i2c_client(struct i2c_client *c, const struct v4l2_dbg_match *match) +{ + int len; + + if (c == NULL || match == NULL) + return 0; + + switch (match->type) { + case V4L2_CHIP_MATCH_I2C_DRIVER: + if (c->driver == NULL || c->driver->driver.name == NULL) + return 0; + len = strlen(c->driver->driver.name); + /* legacy drivers have a ' suffix, don't try to match that */ + if (len && c->driver->driver.name[len - 1] == '\'') + len--; + return len && !strncmp(c->driver->driver.name, match->name, len); + case V4L2_CHIP_MATCH_I2C_ADDR: + return c->addr == match->addr; + default: + return 0; + } +} +EXPORT_SYMBOL(v4l2_chip_match_i2c_client); + +int v4l2_chip_ident_i2c_client(struct i2c_client *c, struct v4l2_dbg_chip_ident *chip, + u32 ident, u32 revision) +{ + if (!v4l2_chip_match_i2c_client(c, &chip->match)) + return 0; + if (chip->ident == V4L2_IDENT_NONE) { + chip->ident = ident; + chip->revision = revision; + } + else { + chip->ident = V4L2_IDENT_AMBIGUOUS; + chip->revision = 0; + } + return 0; +} +EXPORT_SYMBOL(v4l2_chip_ident_i2c_client); + +/* ----------------------------------------------------------------- */ + +/* I2C Helper functions */ + + +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->driver->driver.owner; + /* 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->driver->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->driver == NULL) + goto error; + + /* Lock the module so we can safely get the v4l2_subdev pointer */ + if (!try_module_get(client->driver->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->driver->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 defined(CONFIG_MEDIA_TUNER_TEA5761) || defined(CONFIG_MEDIA_TUNER_TEA5761_MODULE) + 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; + /* 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 (spi && sd == NULL) + 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); + + /* Round to nearest aligned value */ + if (align) + x = (x + (1 << (align - 1))) & mask; + + /* Clamp to aligned value of min and max */ + if (x < min) + x = (min + ~mask) & mask; + else if (x > max) + x = max & mask; + + return x; +} + +/* Bound an image to have a width between wmin and wmax, and height between + * hmin and hmax, inclusive. Additionally, the width will be a multiple of + * 2^walign, the height will be a multiple of 2^halign, and the overall size + * (width*height) will be a multiple of 2^salign. The image may be shrunk + * or enlarged to fit the alignment constraints. + * + * The width or height maximum must not be smaller than the corresponding + * minimum. The alignments must not be so high there are no possible image + * sizes within the allowed bounds. wmin and hmin must be at least 1 + * (don't use 0). If you don't care about a certain alignment, specify 0, + * as 2^0 is 1 and one byte alignment is equivalent to no alignment. If + * you only want to adjust downward, specify a maximum that's the same as + * the initial value. + */ +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); + +/** + * v4l_fill_dv_preset_info - fill description of a digital video preset + * @preset - preset value + * @info - pointer to struct v4l2_dv_enum_preset + * + * drivers can use this helper function to fill description of dv preset + * in info. + */ +int v4l_fill_dv_preset_info(u32 preset, struct v4l2_dv_enum_preset *info) +{ + static const struct v4l2_dv_preset_info { + u16 width; + u16 height; + const char *name; + } dv_presets[] = { + { 0, 0, "Invalid" }, /* V4L2_DV_INVALID */ + { 720, 480, "480p@59.94" }, /* V4L2_DV_480P59_94 */ + { 720, 576, "576p@50" }, /* V4L2_DV_576P50 */ + { 1280, 720, "720p@24" }, /* V4L2_DV_720P24 */ + { 1280, 720, "720p@25" }, /* V4L2_DV_720P25 */ + { 1280, 720, "720p@30" }, /* V4L2_DV_720P30 */ + { 1280, 720, "720p@50" }, /* V4L2_DV_720P50 */ + { 1280, 720, "720p@59.94" }, /* V4L2_DV_720P59_94 */ + { 1280, 720, "720p@60" }, /* V4L2_DV_720P60 */ + { 1920, 1080, "1080i@29.97" }, /* V4L2_DV_1080I29_97 */ + { 1920, 1080, "1080i@30" }, /* V4L2_DV_1080I30 */ + { 1920, 1080, "1080i@25" }, /* V4L2_DV_1080I25 */ + { 1920, 1080, "1080i@50" }, /* V4L2_DV_1080I50 */ + { 1920, 1080, "1080i@60" }, /* V4L2_DV_1080I60 */ + { 1920, 1080, "1080p@24" }, /* V4L2_DV_1080P24 */ + { 1920, 1080, "1080p@25" }, /* V4L2_DV_1080P25 */ + { 1920, 1080, "1080p@30" }, /* V4L2_DV_1080P30 */ + { 1920, 1080, "1080p@50" }, /* V4L2_DV_1080P50 */ + { 1920, 1080, "1080p@60" }, /* V4L2_DV_1080P60 */ + }; + + if (info == NULL || preset >= ARRAY_SIZE(dv_presets)) + return -EINVAL; + + info->preset = preset; + info->width = dv_presets[preset].width; + info->height = dv_presets[preset].height; + strlcpy(info->name, dv_presets[preset].name, sizeof(info->name)); + return 0; +} +EXPORT_SYMBOL_GPL(v4l_fill_dv_preset_info); + +/** + * v4l_match_dv_timings - check if two timings match + * @t1 - compare this v4l2_dv_timings struct... + * @t2 - with this struct. + * @pclock_delta - the allowed pixelclock deviation. + * + * Compare t1 with t2 with a given margin of error for the pixelclock. + */ +bool v4l_match_dv_timings(const struct v4l2_dv_timings *t1, + const struct v4l2_dv_timings *t2, + unsigned pclock_delta) +{ + if (t1->type != t2->type || t1->type != V4L2_DV_BT_656_1120) + return false; + if (t1->bt.width == t2->bt.width && + t1->bt.height == t2->bt.height && + t1->bt.interlaced == t2->bt.interlaced && + t1->bt.polarities == t2->bt.polarities && + t1->bt.pixelclock >= t2->bt.pixelclock - pclock_delta && + t1->bt.pixelclock <= t2->bt.pixelclock + pclock_delta && + t1->bt.hfrontporch == t2->bt.hfrontporch && + t1->bt.vfrontporch == t2->bt.vfrontporch && + t1->bt.vsync == t2->bt.vsync && + t1->bt.vbackporch == t2->bt.vbackporch && + (!t1->bt.interlaced || + (t1->bt.il_vfrontporch == t2->bt.il_vfrontporch && + t1->bt.il_vsync == t2->bt.il_vsync && + t1->bt.il_vbackporch == t2->bt.il_vbackporch))) + return true; + return false; +} +EXPORT_SYMBOL_GPL(v4l_match_dv_timings); + +/* + * CVT defines + * Based on Coordinated Video Timings Standard + * version 1.1 September 10, 2003 + */ + +#define CVT_PXL_CLK_GRAN 250000 /* pixel clock granularity */ + +/* Normal blanking */ +#define CVT_MIN_V_BPORCH 7 /* lines */ +#define CVT_MIN_V_PORCH_RND 3 /* lines */ +#define CVT_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */ + +/* Normal blanking for CVT uses GTF to calculate horizontal blanking */ +#define CVT_CELL_GRAN 8 /* character cell granularity */ +#define CVT_M 600 /* blanking formula gradient */ +#define CVT_C 40 /* blanking formula offset */ +#define CVT_K 128 /* blanking formula scaling factor */ +#define CVT_J 20 /* blanking formula scaling factor */ +#define CVT_C_PRIME (((CVT_C - CVT_J) * CVT_K / 256) + CVT_J) +#define CVT_M_PRIME (CVT_K * CVT_M / 256) + +/* Reduced Blanking */ +#define CVT_RB_MIN_V_BPORCH 7 /* lines */ +#define CVT_RB_V_FPORCH 3 /* lines */ +#define CVT_RB_MIN_V_BLANK 460 /* us */ +#define CVT_RB_H_SYNC 32 /* pixels */ +#define CVT_RB_H_BPORCH 80 /* pixels */ +#define CVT_RB_H_BLANK 160 /* pixels */ + +/** v4l2_detect_cvt - detect if the given timings follow the CVT standard + * @frame_height - the total height of the frame (including blanking) in lines. + * @hfreq - the horizontal frequency in Hz. + * @vsync - the height of the vertical sync in lines. + * @polarities - the horizontal and vertical polarities (same as struct + * v4l2_bt_timings polarities). + * @fmt - the resulting timings. + * + * This function will attempt to detect if the given values correspond to a + * valid CVT format. If so, then it will return true, and fmt will be filled + * in with the found CVT timings. + */ +bool v4l2_detect_cvt(unsigned frame_height, unsigned hfreq, unsigned vsync, + u32 polarities, struct v4l2_dv_timings *fmt) +{ + int v_fp, v_bp, h_fp, h_bp, hsync; + int frame_width, image_height, image_width; + bool reduced_blanking; + unsigned pix_clk; + + if (vsync < 4 || vsync > 7) + return false; + + if (polarities == V4L2_DV_VSYNC_POS_POL) + reduced_blanking = false; + else if (polarities == V4L2_DV_HSYNC_POS_POL) + reduced_blanking = true; + else + return false; + + /* Vertical */ + if (reduced_blanking) { + v_fp = CVT_RB_V_FPORCH; + v_bp = (CVT_RB_MIN_V_BLANK * hfreq + 999999) / 1000000; + v_bp -= vsync + v_fp; + + if (v_bp < CVT_RB_MIN_V_BPORCH) + v_bp = CVT_RB_MIN_V_BPORCH; + } else { + v_fp = CVT_MIN_V_PORCH_RND; + v_bp = (CVT_MIN_VSYNC_BP * hfreq + 999999) / 1000000 - vsync; + + if (v_bp < CVT_MIN_V_BPORCH) + v_bp = CVT_MIN_V_BPORCH; + } + image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1; + + /* Aspect ratio based on vsync */ + switch (vsync) { + case 4: + image_width = (image_height * 4) / 3; + break; + case 5: + image_width = (image_height * 16) / 9; + break; + case 6: + image_width = (image_height * 16) / 10; + break; + case 7: + /* special case */ + if (image_height == 1024) + image_width = (image_height * 5) / 4; + else if (image_height == 768) + image_width = (image_height * 15) / 9; + else + return false; + break; + default: + return false; + } + + image_width = image_width & ~7; + + /* Horizontal */ + if (reduced_blanking) { + pix_clk = (image_width + CVT_RB_H_BLANK) * hfreq; + pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN; + + h_bp = CVT_RB_H_BPORCH; + hsync = CVT_RB_H_SYNC; + h_fp = CVT_RB_H_BLANK - h_bp - hsync; + + frame_width = image_width + CVT_RB_H_BLANK; + } else { + int h_blank; + unsigned ideal_duty_cycle = CVT_C_PRIME - (CVT_M_PRIME * 1000) / hfreq; + + h_blank = (image_width * ideal_duty_cycle + (100 - ideal_duty_cycle) / 2) / + (100 - ideal_duty_cycle); + h_blank = h_blank - h_blank % (2 * CVT_CELL_GRAN); + + if (h_blank * 100 / image_width < 20) { + h_blank = image_width / 5; + h_blank = (h_blank + 0x7) & ~0x7; + } + + pix_clk = (image_width + h_blank) * hfreq; + pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN; + + h_bp = h_blank / 2; + frame_width = image_width + h_blank; + + hsync = (frame_width * 8 + 50) / 100; + hsync = hsync - hsync % CVT_CELL_GRAN; + h_fp = h_blank - hsync - h_bp; + } + + fmt->bt.polarities = polarities; + fmt->bt.width = image_width; + fmt->bt.height = image_height; + fmt->bt.hfrontporch = h_fp; + fmt->bt.vfrontporch = v_fp; + fmt->bt.hsync = hsync; + fmt->bt.vsync = vsync; + fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync; + fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync; + fmt->bt.pixelclock = pix_clk; + fmt->bt.standards = V4L2_DV_BT_STD_CVT; + if (reduced_blanking) + fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING; + return true; +} +EXPORT_SYMBOL_GPL(v4l2_detect_cvt); + +/* + * GTF defines + * Based on Generalized Timing Formula Standard + * Version 1.1 September 2, 1999 + */ + +#define GTF_PXL_CLK_GRAN 250000 /* pixel clock granularity */ + +#define GTF_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */ +#define GTF_V_FP 1 /* vertical front porch (lines) */ +#define GTF_CELL_GRAN 8 /* character cell granularity */ + +/* Default */ +#define GTF_D_M 600 /* blanking formula gradient */ +#define GTF_D_C 40 /* blanking formula offset */ +#define GTF_D_K 128 /* blanking formula scaling factor */ +#define GTF_D_J 20 /* blanking formula scaling factor */ +#define GTF_D_C_PRIME ((((GTF_D_C - GTF_D_J) * GTF_D_K) / 256) + GTF_D_J) +#define GTF_D_M_PRIME ((GTF_D_K * GTF_D_M) / 256) + +/* Secondary */ +#define GTF_S_M 3600 /* blanking formula gradient */ +#define GTF_S_C 40 /* blanking formula offset */ +#define GTF_S_K 128 /* blanking formula scaling factor */ +#define GTF_S_J 35 /* blanking formula scaling factor */ +#define GTF_S_C_PRIME ((((GTF_S_C - GTF_S_J) * GTF_S_K) / 256) + GTF_S_J) +#define GTF_S_M_PRIME ((GTF_S_K * GTF_S_M) / 256) + +/** v4l2_detect_gtf - detect if the given timings follow the GTF standard + * @frame_height - the total height of the frame (including blanking) in lines. + * @hfreq - the horizontal frequency in Hz. + * @vsync - the height of the vertical sync in lines. + * @polarities - the horizontal and vertical polarities (same as struct + * v4l2_bt_timings polarities). + * @aspect - preferred aspect ratio. GTF has no method of determining the + * aspect ratio in order to derive the image width from the + * image height, so it has to be passed explicitly. Usually + * the native screen aspect ratio is used for this. If it + * is not filled in correctly, then 16:9 will be assumed. + * @fmt - the resulting timings. + * + * This function will attempt to detect if the given values correspond to a + * valid GTF format. If so, then it will return true, and fmt will be filled + * in with the found GTF timings. + */ +bool v4l2_detect_gtf(unsigned frame_height, + unsigned hfreq, + unsigned vsync, + u32 polarities, + struct v4l2_fract aspect, + struct v4l2_dv_timings *fmt) +{ + int pix_clk; + int v_fp, v_bp, h_fp, h_bp, hsync; + int frame_width, image_height, image_width; + bool default_gtf; + int h_blank; + + if (vsync != 3) + return false; + + if (polarities == V4L2_DV_VSYNC_POS_POL) + default_gtf = true; + else if (polarities == V4L2_DV_HSYNC_POS_POL) + default_gtf = false; + else + return false; + + /* Vertical */ + v_fp = GTF_V_FP; + v_bp = (GTF_MIN_VSYNC_BP * hfreq + 999999) / 1000000 - vsync; + image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1; + + if (aspect.numerator == 0 || aspect.denominator == 0) { + aspect.numerator = 16; + aspect.denominator = 9; + } + image_width = ((image_height * aspect.numerator) / aspect.denominator); + + /* Horizontal */ + if (default_gtf) + h_blank = ((image_width * GTF_D_C_PRIME * hfreq) - + (image_width * GTF_D_M_PRIME * 1000) + + (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000) / 2) / + (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000); + else + h_blank = ((image_width * GTF_S_C_PRIME * hfreq) - + (image_width * GTF_S_M_PRIME * 1000) + + (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000) / 2) / + (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000); + + h_blank = h_blank - h_blank % (2 * GTF_CELL_GRAN); + frame_width = image_width + h_blank; + + pix_clk = (image_width + h_blank) * hfreq; + pix_clk = pix_clk / GTF_PXL_CLK_GRAN * GTF_PXL_CLK_GRAN; + + hsync = (frame_width * 8 + 50) / 100; + hsync = hsync - hsync % GTF_CELL_GRAN; + + h_fp = h_blank / 2 - hsync; + h_bp = h_blank / 2; + + fmt->bt.polarities = polarities; + fmt->bt.width = image_width; + fmt->bt.height = image_height; + fmt->bt.hfrontporch = h_fp; + fmt->bt.vfrontporch = v_fp; + fmt->bt.hsync = hsync; + fmt->bt.vsync = vsync; + fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync; + fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync; + fmt->bt.pixelclock = pix_clk; + fmt->bt.standards = V4L2_DV_BT_STD_GTF; + if (!default_gtf) + fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING; + return true; +} +EXPORT_SYMBOL_GPL(v4l2_detect_gtf); + +/** v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes + * 0x15 and 0x16 from the EDID. + * @hor_landscape - byte 0x15 from the EDID. + * @vert_portrait - byte 0x16 from the EDID. + * + * Determines the aspect ratio from the EDID. + * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2: + * "Horizontal and Vertical Screen Size or Aspect Ratio" + */ +struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait) +{ + struct v4l2_fract aspect = { 16, 9 }; + u32 tmp; + u8 ratio; + + /* Nothing filled in, fallback to 16:9 */ + if (!hor_landscape && !vert_portrait) + return aspect; + /* Both filled in, so they are interpreted as the screen size in cm */ + if (hor_landscape && vert_portrait) { + aspect.numerator = hor_landscape; + aspect.denominator = vert_portrait; + return aspect; + } + /* Only one is filled in, so interpret them as a ratio: + (val + 99) / 100 */ + ratio = hor_landscape | vert_portrait; + /* Change some rounded values into the exact aspect ratio */ + if (ratio == 79) { + aspect.numerator = 16; + aspect.denominator = 9; + } else if (ratio == 34) { + aspect.numerator = 4; + aspect.numerator = 3; + } else if (ratio == 68) { + aspect.numerator = 15; + aspect.numerator = 9; + } else { + aspect.numerator = hor_landscape + 99; + aspect.denominator = 100; + } + if (hor_landscape) + return aspect; + /* The aspect ratio is for portrait, so swap numerator and denominator */ + tmp = aspect.denominator; + aspect.denominator = aspect.numerator; + aspect.numerator = tmp; + return aspect; +} +EXPORT_SYMBOL_GPL(v4l2_calc_aspect_ratio); + +const struct v4l2_frmsize_discrete *v4l2_find_nearest_format( + const struct v4l2_discrete_probe *probe, + s32 width, s32 height) +{ + int i; + u32 error, min_error = UINT_MAX; + const struct v4l2_frmsize_discrete *size, *best = NULL; + + if (!probe) + return best; + + for (i = 0, size = probe->sizes; i < probe->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); |