[media] v4l: omap4iss: Add support for OMAP4 camera interface - Resizer

This adds a very simplistic driver to utilize the CSI2A interface inside
the ISS subsystem in OMAP4, and dump the data to memory.
Check Documentation/video4linux/omap4_camera.txt for details.
This commit adds resizer support.
[Port the driver to v3.12-rc3, including the following changes
- Don't include plat/ headers
- Don't use cpu_is_omap44xx() macro
- Don't depend on EXPERIMENTAL
- Fix s_crop operation prototype
- Update link_notify prototype
- Rename media_entity_remote_source to media_entity_remote_pad]
Signed-off-by: Sergio Aguirre <sergio.a.aguirre@gmail.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/media/omap4iss/iss_resizer.h

+/*
+ * TI OMAP4 ISS V4L2 Driver - ISP RESIZER module
+ *
+ * Copyright (C) 2012 Texas Instruments, Inc.
+ *
+ * Author: Sergio Aguirre <sergio.a.aguirre@gmail.com>
+ *
+ * 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.
+ */
+
+#ifndef OMAP4_ISS_RESIZER_H
+#define OMAP4_ISS_RESIZER_H
+
+#include "iss_video.h"
+
+enum resizer_input_entity {
+	RESIZER_INPUT_NONE,
+	RESIZER_INPUT_IPIPE,
+	RESIZER_INPUT_IPIPEIF
+};
+
+#define RESIZER_OUTPUT_MEMORY		(1 << 0)
+
+/* Sink and source RESIZER pads */
+#define RESIZER_PAD_SINK			0
+#define RESIZER_PAD_SOURCE_MEM			1
+#define RESIZER_PADS_NUM			2
+
+/*
+ * struct iss_resizer_device - Structure for the RESIZER module to store its own
+ *			    information
+ * @subdev: V4L2 subdevice
+ * @pads: Sink and source media entity pads
+ * @formats: Active video formats
+ * @input: Active input
+ * @output: Active outputs
+ * @video_out: Output video node
+ * @error: A hardware error occurred during capture
+ * @state: Streaming state
+ * @wait: Wait queue used to stop the module
+ * @stopping: Stopping state
+ */
+struct iss_resizer_device {
+	struct v4l2_subdev subdev;
+	struct media_pad pads[RESIZER_PADS_NUM];
+	struct v4l2_mbus_framefmt formats[RESIZER_PADS_NUM];
+
+	enum resizer_input_entity input;
+	unsigned int output;
+	struct iss_video video_out;
+	unsigned int error;
+
+	enum iss_pipeline_stream_state state;
+	wait_queue_head_t wait;
+	atomic_t stopping;
+};
+
+struct iss_device;
+
+int omap4iss_resizer_init(struct iss_device *iss);
+void omap4iss_resizer_cleanup(struct iss_device *iss);
+int omap4iss_resizer_register_entities(struct iss_resizer_device *resizer,
+	struct v4l2_device *vdev);
+void omap4iss_resizer_unregister_entities(struct iss_resizer_device *resizer);
+
+int omap4iss_resizer_busy(struct iss_resizer_device *resizer);
+void omap4iss_resizer_isr(struct iss_resizer_device *resizer, u32 events);
+void omap4iss_resizer_restore_context(struct iss_device *iss);
+void omap4iss_resizer_max_rate(struct iss_resizer_device *resizer,
+	unsigned int *max_rate);
+
+#endif	/* OMAP4_ISS_RESIZER_H */