path: root/drivers/media/video/soc_camera.c

/*
 * camera image capture (abstract) bus driver
 *
 * Copyright (C) 2008, Guennadi Liakhovetski <kernel@pengutronix.de>
 *
 * This driver provides an interface between platform-specific camera
 * busses and camera devices. It should be used if the camera is
 * connected not over a "proper" bus like PCI or USB, but over a
 * special bus, like, for example, the Quick Capture interface on PXA270
 * SoCs. Later it should also be used for i.MX31 SoCs from Freescale.
 * It can handle multiple cameras and / or multiple busses, which can
 * be used, e.g., in stereo-vision applications.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/device.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/vmalloc.h>

#include <media/soc_camera.h>
#include <media/v4l2-common.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-ioctl.h>
#include <media/videobuf-core.h>

/* Default to VGA resolution */
#define DEFAULT_WIDTH	640
#define DEFAULT_HEIGHT	480

static LIST_HEAD(hosts);
static LIST_HEAD(devices);
static DEFINE_MUTEX(list_lock);

const struct soc_camera_data_format *soc_camera_format_by_fourcc(
	struct soc_camera_device *icd, unsigned int fourcc)
{
	unsigned int i;

	for (i = 0; i < icd->num_formats; i++)
		if (icd->formats[i].fourcc == fourcc)
			return icd->formats + i;
	return NULL;
}
EXPORT_SYMBOL(soc_camera_format_by_fourcc);

const struct soc_camera_format_xlate *soc_camera_xlate_by_fourcc(
	struct soc_camera_device *icd, unsigned int fourcc)
{
	unsigned int i;

	for (i = 0; i < icd->num_user_formats; i++)
		if (icd->user_formats[i].host_fmt->fourcc == fourcc)
			return icd->user_formats + i;
	return NULL;
}
EXPORT_SYMBOL(soc_camera_xlate_by_fourcc);

/**
 * soc_camera_apply_sensor_flags() - apply platform SOCAM_SENSOR_INVERT_* flags
 * @icl:	camera platform parameters
 * @flags:	flags to be inverted according to platform configuration
 * @return:	resulting flags
 */
unsigned long soc_camera_apply_sensor_flags(struct soc_camera_link *icl,
					    unsigned long flags)
{
	unsigned long f;

	/* If only one of the two polarities is supported, switch to the opposite */
	if (icl->flags & SOCAM_SENSOR_INVERT_HSYNC) {
		f = flags & (SOCAM_HSYNC_ACTIVE_HIGH | SOCAM_HSYNC_ACTIVE_LOW);
		if (f == SOCAM_HSYNC_ACTIVE_HIGH || f == SOCAM_HSYNC_ACTIVE_LOW)
			flags ^= SOCAM_HSYNC_ACTIVE_HIGH | SOCAM_HSYNC_ACTIVE_LOW;
	}

	if (icl->flags & SOCAM_SENSOR_INVERT_VSYNC) {
		f = flags & (SOCAM_VSYNC_ACTIVE_HIGH | SOCAM_VSYNC_ACTIVE_LOW);
		if (f == SOCAM_VSYNC_ACTIVE_HIGH || f == SOCAM_VSYNC_ACTIVE_LOW)
			flags ^= SOCAM_VSYNC_ACTIVE_HIGH | SOCAM_VSYNC_ACTIVE_LOW;
	}

	if (icl->flags & SOCAM_SENSOR_INVERT_PCLK) {
		f = flags & (SOCAM_PCLK_SAMPLE_RISING | SOCAM_PCLK_SAMPLE_FA