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

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

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

const static struct soc_camera_data_format*
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;
}

static int soc_camera_try_fmt_cap(struct file *file, void *priv,
				  struct v4l2_format *f)
{
	struct soc_camera_file *icf = file->private_data;
	struct soc_camera_device *icd = icf->icd;
	struct soc_camera_host *ici =
		to_soc_camera_host(icd->dev.parent);
	enum v4l2_field field;
	const struct soc_camera_data_format *fmt;
	int ret;

	WARN_ON(priv != file->private_data);

	fmt = format_by_fourcc(icd, f->fmt.pix.pixelformat);
	if (!fmt) {
		dev_dbg(&icd->dev, "invalid format 0x%08x\n",
			f->fmt.pix.pixelformat);
		return -EINVAL;
	}

	dev_dbg(&icd->dev, "fmt: 0x%08x\n", fmt->fourcc);

	field = f->fmt.pix.field;

	if (field == V4L2_FIELD_ANY) {
		field = V4L2_FIELD_NONE;
	} else if (V4L2_FIELD_NONE != field) {
		dev_err(&icd->dev, "Field type invalid.\n");
		return -EINVAL;
	}

	/* test physical bus parameters */
	ret = ici->ops->try_bus_param(icd, f->fmt.pix.pixelformat);
	if (ret)
		return ret;

	/* limit format to hardware capabilities */
	ret = ici->ops->try_fmt_cap(icd, f);

	/* calculate missing fields */
	f->fmt.pix.field = field;
	f->fmt.pix.bytesperline =
		(f->fmt.pix.width * fmt->depth) >> 3;
	f->fmt.pix.sizeimage =
		f->fmt.pix.height * f->fmt.pix.bytesperline;

	return ret;
}

static int soc_camera_enum_input(struct file *file, void *priv,
				 struct v4l2_input *inp)
{
	if (inp->index != 0)
		return -EINVAL;

	inp->type = V4L2_INPUT_TYPE_CAMERA;
	inp->std = V4L2_STD_UNKNOWN;
	strcpy(inp->name, "Camera");

	return 0;
}

static int soc_camera_g_input(struct file *file, void *priv, unsigned int *i)
{
	*i = 0;

	return 0;
}

static int soc_camera_s_input(struct file *file, void *priv, unsigned int i)
{
	if (i > 0)
		return -EINVAL;

	return 0;
}

static int soc_camera_s_std(struct file *file, void *priv, v4l2_std_id *a)
{
	return 0;
}

static int soc_camera_reqbufs(struct file *file, void *priv,
			      struct v4l2_requestbuffers *p)
{
	int ret;
	struct soc_camera_file *icf = file->private_data;
	struct soc_camera_device *icd = icf->icd;
	struct soc_camera_host