/*
* 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