V4L/DVB: [v5,2/2] v4l: Add a mem-to-mem videobuf framework test device

This is a virtual device driver for testing the memory-to-memory framework.

This virtual device uses in-memory buffers for both its source and destination.
It is capable of multi-instance, multi-buffer-per-transaction operation
(via the mem2mem framework).

[mchehab@redhat.com: use videobuf_queue_to_vaddr instead of the removed videobuf_queue_to_vmalloc]
Signed-off-by: Pawel Osciak <p.osciak@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Vaibhav Hiremath <hvaibhav@ti.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

3 files changed, 1064 insertions, 0 deletions

diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
index f8cbd4adebfd..16decdd6e28c 100644
--- a/drivers/media/video/Kconfig
+++ b/drivers/media/video/Kconfig
@@ -1135,3 +1135,17 @@ menuconfig V4L_MEM2MEM_DRIVERS
           use system memory for both source and destination buffers, as opposed
           to capture and output drivers, which use memory buffers for just
           one of those.
+
+if V4L_MEM2MEM_DRIVERS
+
+config VIDEO_MEM2MEM_TESTDEV
+        tristate "Virtual test device for mem2mem framework"
+        depends on VIDEO_DEV && VIDEO_V4L2
+        select VIDEOBUF_VMALLOC
+        select V4L2_MEM2MEM_DEV
+        default n
+        ---help---
+          This is a virtual test device for the memory-to-memory driver
+          framework.
+
+endif # V4L_MEM2MEM_DRIVERS
diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile
index b57be2f542e8..a688a0f43879 100644
--- a/drivers/media/video/Makefile
+++ b/drivers/media/video/Makefile
@@ -151,6 +151,7 @@ obj-$(CONFIG_VIDEO_IVTV) += ivtv/
 obj-$(CONFIG_VIDEO_CX18) += cx18/
 
 obj-$(CONFIG_VIDEO_VIVI) += vivi.o
+obj-$(CONFIG_VIDEO_MEM2MEM_TESTDEV) += mem2mem_testdev.o
 obj-$(CONFIG_VIDEO_CX23885) += cx23885/
 
 obj-$(CONFIG_VIDEO_AK881X)              += ak881x.o
diff --git a/drivers/media/video/mem2mem_testdev.c b/drivers/media/video/mem2mem_testdev.c
new file mode 100644
index 000000000000..baf211b9f6ce
--- /dev/null
+++ b/drivers/media/video/mem2mem_testdev.c
@@ -0,0 +1,1049 @@
+/*
+ * A virtual v4l2-mem2mem example device.
+ *
+ * This is a virtual device driver for testing mem-to-mem videobuf framework.
+ * It simulates a device that uses memory buffers for both source and
+ * destination, processes the data and issues an "irq" (simulated by a timer).
+ * The device is capable of multi-instance, multi-buffer-per-transaction
+ * operation (via the mem2mem framework).
+ *
+ * Copyright (c) 2009-2010 Samsung Electronics Co., Ltd.
+ * Pawel Osciak, <p.osciak@samsung.com>
+ * Marek Szyprowski, <m.szyprowski@samsung.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
+ */
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/version.h>
+#include <linux/timer.h>
+#include <linux/sched.h>
+
+#include <linux/platform_device.h>
+#include <media/v4l2-mem2mem.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf-vmalloc.h>
+
+#define MEM2MEM_TEST_MODULE_NAME "mem2mem-testdev"
+
+MODULE_DESCRIPTION("Virtual device for mem2mem framework testing");
+MODULE_AUTHOR("Pawel Osciak, <p.osciak@samsung.com>");
+MODULE_LICENSE("GPL");
+
+
+#define MIN_W 32
+#define MIN_H 32
+#define MAX_W 640
+#define MAX_H 480
+#define DIM_ALIGN_MASK 0x08 /* 8-alignment for dimensions */
+
+/* Flags that indicate a format can be used for capture/output */
+#define MEM2MEM_CAPTURE (1 << 0)
+#define MEM2MEM_OUTPUT  (1 << 1)
+
+#define MEM2MEM_NAME            "m2m-testdev"
+
+/* Per queue */
+#define MEM2MEM_DEF_NUM_BUFS    VIDEO_MAX_FRAME
+/* In bytes, per queue */
+#define MEM2MEM_VID_MEM_LIMIT   (16 * 1024 * 1024)
+
+/* Default transaction time in msec */
+#define MEM2MEM_DEF_TRANSTIME   1000
+/* Default number of buffers per transaction */
+#define MEM2MEM_DEF_TRANSLEN    1
+#define MEM2MEM_COLOR_STEP      (0xff >> 4)
+#define MEM2MEM_NUM_TILES       8
+
+#define dprintk(dev, fmt, arg...) \
+        v4l2_dbg(1, 1, &dev->v4l2_dev, "%s: " fmt, __func__, ## arg)
+
+
+void m2mtest_dev_release(struct device *dev)
+{}
+
+static struct platform_device m2mtest_pdev = {
+        .name           = MEM2MEM_NAME,
+        .dev.release    = m2mtest_dev_release,
+};
+
+struct m2mtest_fmt {
+        char    *name;
+        u32     fourcc;
+        int     depth;
+        /* Types the format can be used for */
+        u32     types;
+};
+
+static struct m2mtest_fmt formats[] = {
+        {
+                .name   = "RGB565 (BE)",
+                .fourcc = V4L2_PIX_FMT_RGB565X, /* rrrrrggg gggbbbbb */
+                .depth  = 16,
+                /* Both capture and output format */
+                .types  = MEM2MEM_CAPTURE | MEM2MEM_OUTPUT,
+        },
+        {
+                .name   = "4:2:2, packed, YUYV",
+                .fourcc = V4L2_PIX_FMT_YUYV,
+                .depth  = 16,
+                /* Output-only format */
+                .types  = MEM2MEM_OUTPUT,
+        },
+};
+
+/* Per-queue, driver-specific private data */
+struct m2mtest_q_data {
+        unsigned int            width;
+        unsigned int            height;
+        unsigned int            sizeimage;
+        struct m2mtest_fmt      *fmt;
+};
+
+enum {
+        V4L2_M2M_SRC = 0,
+        V4L2_M2M_DST = 1,
+};
+
+/* Source and destination queue data */
+static struct m2mtest_q_data q_data[2];
+
+static struct m2mtest_q_data *get_q_data(enum v4l2_buf_type type)
+{
+        switch (type) {
+        case V4L2_BUF_TYPE_VIDEO_OUTPUT:
+                return &q_data[V4L2_M2M_SRC];
+        case V4L2_BUF_TYPE_VIDEO_CAPTURE:
+                return &q_data[V4L2_M2M_DST];
+        default:
+                BUG();
+        }
+        return NULL;
+}
+
+#define V4L2_CID_TRANS_TIME_MSEC        V4L2_CID_PRIVATE_BASE
+#define V4L2_CID_TRANS_NUM_BUFS         (V4L2_CID_PRIVATE_BASE + 1)
+
+static struct v4l2_queryctrl m2mtest_ctrls[] = {
+        {
+                .id             = V4L2_CID_TRANS_TIME_MSEC,
+                .type           = V4L2_CTRL_TYPE_INTEGER,
+                .name           = "Transaction time (msec)",
+                .minimum        = 1,
+                .maximum        = 10000,
+                .step           = 100,
+                .default_value  = 1000,
+                .flags          = 0,
+        }, {
+                .id             = V4L2_CID_TRANS_NUM_BUFS,
+                .type           = V4L2_CTRL_TYPE_INTEGER,
+                .name           = "Buffers per transaction",
+                .minimum        = 1,
+                .maximum        = MEM2MEM_DEF_NUM_BUFS,
+                .step           = 1,
+                .default_value  = 1,
+                .flags          = 0,
+        },
+};
+
+#define NUM_FORMATS ARRAY_SIZE(formats)
+
+static struct m2mtest_fmt *find_format(struct v4l2_format *f)
+{
+        struct m2mtest_fmt *fmt;
+        unsigned int k;
+
+        for (k = 0; k < NUM_FORMATS; k++) {
+                fmt = &formats[k];
+                if (fmt->fourcc == f->fmt.pix.pixelformat)
+                        break;
+        }
+
+        if (k == NUM_FORMATS)
+                return NULL;
+
+        return &formats[k];
+}
+
+struct m2mtest_dev {
+        struct v4l2_device      v4l2_dev;
+        struct video_device     *vfd;
+
+        atomic_t                num_inst;
+        struct mutex            dev_mutex;
+        spinlock_t              irqlock;
+
+        struct timer_list       timer;
+
+        struct v4l2_m2m_dev     *m2m_dev;
+};
+
+struct m2mtest_ctx {
+        struct m2mtest_dev      *dev;
+
+        /* Processed buffers in this transaction */
+        u8                      num_processed;
+
+        /* Transaction length (i.e. how many buffers per transaction) */
+        u32                     translen;
+        /* Transaction time (i.e. simulated processing time) in milliseconds */
+        u32                     transtime;
+
+        /* Abort requested by m2m */
+        int                     aborting;
+
+        struct v4l2_m2m_ctx     *m2m_ctx;
+};
+
+struct m2mtest_buffer {
+        /* vb must be first! */
+        struct videobuf_buffer  vb;
+};
+
+static struct v4l2_queryctrl *get_ctrl(int id)
+{
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(m2mtest_ctrls); ++i) {
+                if (id == m2mtest_ctrls[i].id)
+                        return &m2mtest_ctrls[i];
+        }
+
+        return NULL;
+}
+
+static int device_process(struct m2mtest_ctx *ctx,
+                          struct m2mtest_buffer *in_buf,
+                          struct m2mtest_buffer *out_buf)
+{
+        struct m2mtest_dev *dev = ctx->dev;
+        u8 *p_in, *p_out;
+        int x, y, t, w;
+        int tile_w, bytes_left;
+        struct videobuf_queue *src_q;
+        struct videobuf_queue *dst_q;
+
+        src_q = v4l2_m2m_get_src_vq(ctx->m2m_ctx);
+        dst_q = v4l2_m2m_get_dst_vq(ctx->m2m_ctx);
+        p_in = videobuf_queue_to_vaddr(src_q, &in_buf->vb);
+        p_out = videobuf_queue_to_vaddr(dst_q, &out_buf->vb);
+        if (!p_in || !p_out) {
+                v4l2_err(&dev->v4l2_dev,
+                         "Acquiring kernel pointers to buffers failed\n");
+                return -EFAULT;
+        }
+
+        if (in_buf->vb.size < out_buf->vb.size) {
+                v4l2_err(&dev->v4l2_dev, "Output buffer is too small\n");
+                return -EINVAL;
+        }
+
+        tile_w = (in_buf->vb.width * (q_data[V4L2_M2M_DST].fmt->depth >> 3))
+                / MEM2MEM_NUM_TILES;
+        bytes_left = in_buf->vb.bytesperline - tile_w * MEM2MEM_NUM_TILES;
+        w = 0;
+
+        for (y = 0; y < in_buf->vb.height; ++y) {
+                for (t = 0; t < MEM2MEM_NUM_TILES; ++t) {
+                        if (w & 0x1) {
+                                for (x = 0; x < tile_w; ++x)
+                                        *p_out++ = *p_in++ + MEM2MEM_COLOR_STEP;
+                        } else {
+                                for (x = 0; x < tile_w; ++x)
+                                        *p_out++ = *p_in++ - MEM2MEM_COLOR_STEP;
+                        }
+                        ++w;
+                }
+                p_in += bytes_left;
+                p_out += bytes_left;
+        }
+
+        return 0;
+}
+
+static void schedule_irq(struct m2mtest_dev *dev, int msec_timeout)
+{
+        dprintk(dev, "Scheduling a simulated irq\n");
+        mod_timer(&dev->timer, jiffies + msecs_to_jiffies(msec_timeout));
+}
+
+/*
+ * mem2mem callbacks
+ */
+
+/**
+ * job_ready() - check whether an instance is ready to be scheduled to run
+ */
+static int job_ready(void *priv)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        if (v4l2_m2m_num_src_bufs_ready(ctx->m2m_ctx) < ctx->translen
+            || v4l2_m2m_num_dst_bufs_ready(ctx->m2m_ctx) < ctx->translen) {
+                dprintk(ctx->dev, "Not enough buffers available\n");
+                return 0;
+        }
+
+        return 1;
+}
+
+static void job_abort(void *priv)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        /* Will cancel the transaction in the next interrupt handler */
+        ctx->aborting = 1;
+}
+
+/* device_run() - prepares and starts the device
+ *
+ * This simulates all the immediate preparations required before starting
+ * a device. This will be called by the framework when it decides to schedule
+ * a particular instance.
+ */
+static void device_run(void *priv)
+{
+        struct m2mtest_ctx *ctx = priv;
+        struct m2mtest_dev *dev = ctx->dev;
+        struct m2mtest_buffer *src_buf, *dst_buf;
+
+        src_buf = v4l2_m2m_next_src_buf(ctx->m2m_ctx);
+        dst_buf = v4l2_m2m_next_dst_buf(ctx->m2m_ctx);
+
+        device_process(ctx, src_buf, dst_buf);
+
+        /* Run a timer, which simulates a hardware irq  */
+        schedule_irq(dev, ctx->transtime);
+}
+
+
+static void device_isr(unsigned long priv)
+{
+        struct m2mtest_dev *m2mtest_dev = (struct m2mtest_dev *)priv;
+        struct m2mtest_ctx *curr_ctx;
+        struct m2mtest_buffer *src_buf, *dst_buf;
+        unsigned long flags;
+
+        curr_ctx = v4l2_m2m_get_curr_priv(m2mtest_dev->m2m_dev);
+
+        if (NULL == curr_ctx) {
+                printk(KERN_ERR
+                        "Instance released before the end of transaction\n");
+                return;
+        }
+
+        src_buf = v4l2_m2m_src_buf_remove(curr_ctx->m2m_ctx);
+        dst_buf = v4l2_m2m_dst_buf_remove(curr_ctx->m2m_ctx);
+        curr_ctx->num_processed++;
+
+        if (curr_ctx->num_processed == curr_ctx->translen
+            || curr_ctx->aborting) {
+                dprintk(curr_ctx->dev, "Finishing transaction\n");
+                curr_ctx->num_processed = 0;
+                spin_lock_irqsave(&m2mtest_dev->irqlock, flags);
+                src_buf->vb.state = dst_buf->vb.state = VIDEOBUF_DONE;
+                wake_up(&src_buf->vb.done);
+                wake_up(&dst_buf->vb.done);
+                spin_unlock_irqrestore(&m2mtest_dev->irqlock, flags);
+                v4l2_m2m_job_finish(m2mtest_dev->m2m_dev, curr_ctx->m2m_ctx);
+        } else {
+                spin_lock_irqsave(&m2mtest_dev->irqlock, flags);
+                src_buf->vb.state = dst_buf->vb.state = VIDEOBUF_DONE;
+                wake_up(&src_buf->vb.done);
+                wake_up(&dst_buf->vb.done);
+                spin_unlock_irqrestore(&m2mtest_dev->irqlock, flags);
+                device_run(curr_ctx);
+        }
+}
+
+
+/*
+ * video ioctls
+ */
+static int vidioc_querycap(struct file *file, void *priv,
+                           struct v4l2_capability *cap)
+{
+        strncpy(cap->driver, MEM2MEM_NAME, sizeof(cap->driver) - 1);
+        strncpy(cap->card, MEM2MEM_NAME, sizeof(cap->card) - 1);
+        cap->bus_info[0] = 0;
+        cap->version = KERNEL_VERSION(0, 1, 0);
+        cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT
+                          | V4L2_CAP_STREAMING;
+
+        return 0;
+}
+
+static int enum_fmt(struct v4l2_fmtdesc *f, u32 type)
+{
+        int i, num;
+        struct m2mtest_fmt *fmt;
+
+        num = 0;
+
+        for (i = 0; i < NUM_FORMATS; ++i) {
+                if (formats[i].types & type) {
+                        /* index-th format of type type found ? */
+                        if (num == f->index)
+                                break;
+                        /* Correct type but haven't reached our index yet,
+                         * just increment per-type index */
+                        ++num;
+                }
+        }
+
+        if (i < NUM_FORMATS) {
+                /* Format found */
+                fmt = &formats[i];
+                strncpy(f->description, fmt->name, sizeof(f->description) - 1);
+                f->pixelformat = fmt->fourcc;
+                return 0;
+        }
+
+        /* Format not found */
+        return -EINVAL;
+}
+
+static int vidioc_enum_fmt_vid_cap(struct file *file, void *priv,
+                                   struct v4l2_fmtdesc *f)
+{
+        return enum_fmt(f, MEM2MEM_CAPTURE);
+}
+
+static int vidioc_enum_fmt_vid_out(struct file *file, void *priv,
+                                   struct v4l2_fmtdesc *f)
+{
+        return enum_fmt(f, MEM2MEM_OUTPUT);
+}
+
+static int vidioc_g_fmt(struct m2mtest_ctx *ctx, struct v4l2_format *f)
+{
+        struct videobuf_queue *vq;
+        struct m2mtest_q_data *q_data;
+
+        vq = v4l2_m2m_get_vq(ctx->m2m_ctx, f->type);
+        if (!vq)
+                return -EINVAL;
+
+        q_data = get_q_data(f->type);
+
+        f->fmt.pix.width        = q_data->width;
+        f->fmt.pix.height       = q_data->height;
+        f->fmt.pix.field        = vq->field;
+        f->fmt.pix.pixelformat  = q_data->fmt->fourcc;
+        f->fmt.pix.bytesperline = (q_data->width * q_data->fmt->depth) >> 3;
+        f->fmt.pix.sizeimage    = q_data->sizeimage;
+
+        return 0;
+}
+
+static int vidioc_g_fmt_vid_out(struct file *file, void *priv,
+                                struct v4l2_format *f)
+{
+        return vidioc_g_fmt(priv, f);
+}
+
+static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
+                                struct v4l2_format *f)
+{
+        return vidioc_g_fmt(priv, f);
+}
+
+static int vidioc_try_fmt(struct v4l2_format *f, struct m2mtest_fmt *fmt)
+{
+        enum v4l2_field field;
+
+        field = f->fmt.pix.field;
+
+        if (field == V4L2_FIELD_ANY)
+                field = V4L2_FIELD_NONE;
+        else if (V4L2_FIELD_NONE != field)
+                return -EINVAL;
+
+        /* V4L2 specification suggests the driver corrects the format struct
+         * if any of the dimensions is unsupported */
+        f->fmt.pix.field = field;
+
+        if (f->fmt.pix.height < MIN_H)
+                f->fmt.pix.height = MIN_H;
+        else if (f->fmt.pix.height > MAX_H)
+                f->fmt.pix.height = MAX_H;
+
+        if (f->fmt.pix.width < MIN_W)
+                f->fmt.pix.width = MIN_W;
+        else if (f->fmt.pix.width > MAX_W)
+                f->fmt.pix.width = MAX_W;
+
+        f->fmt.pix.width &= ~DIM_ALIGN_MASK;
+        f->fmt.pix.bytesperline = (f->fmt.pix.width * fmt->depth) >> 3;
+        f->fmt.pix.sizeimage = f->fmt.pix.height * f->fmt.pix.bytesperline;
+
+        return 0;
+}
+
+static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
+                                  struct v4l2_format *f)
+{
+        struct m2mtest_fmt *fmt;
+        struct m2mtest_ctx *ctx = priv;
+
+        fmt = find_format(f);
+        if (!fmt || !(fmt->types & MEM2MEM_CAPTURE)) {
+                v4l2_err(&ctx->dev->v4l2_dev,
+                         "Fourcc format (0x%08x) invalid.\n",
+                         f->fmt.pix.pixelformat);
+                return -EINVAL;
+        }
+
+        return vidioc_try_fmt(f, fmt);
+}
+
+static int vidioc_try_fmt_vid_out(struct file *file, void *priv,
+                                  struct v4l2_format *f)
+{
+        struct m2mtest_fmt *fmt;
+        struct m2mtest_ctx *ctx = priv;
+
+        fmt = find_format(f);
+        if (!fmt || !(fmt->types & MEM2MEM_OUTPUT)) {
+                v4l2_err(&ctx->dev->v4l2_dev,
+                         "Fourcc format (0x%08x) invalid.\n",
+                         f->fmt.pix.pixelformat);
+                return -EINVAL;
+        }
+
+        return vidioc_try_fmt(f, fmt);
+}
+
+static int vidioc_s_fmt(struct m2mtest_ctx *ctx, struct v4l2_format *f)
+{
+        struct m2mtest_q_data *q_data;
+        struct videobuf_queue *vq;
+        int ret = 0;
+
+        vq = v4l2_m2m_get_vq(ctx->m2m_ctx, f->type);
+        if (!vq)
+                return -EINVAL;
+
+        q_data = get_q_data(f->type);
+        if (!q_data)
+                return -EINVAL;
+
+        mutex_lock(&vq->vb_lock);
+
+        if (videobuf_queue_is_busy(vq)) {
+                v4l2_err(&ctx->dev->v4l2_dev, "%s queue busy\n", __func__);
+                ret = -EBUSY;
+                goto out;
+        }
+
+        q_data->fmt             = find_format(f);
+        q_data->width           = f->fmt.pix.width;
+        q_data->height          = f->fmt.pix.height;
+        q_data->sizeimage       = q_data->width * q_data->height
+                                * q_data->fmt->depth >> 3;
+        vq->field               = f->fmt.pix.field;
+
+        dprintk(ctx->dev,
+                "Setting format for type %d, wxh: %dx%d, fmt: %d\n",
+                f->type, q_data->width, q_data->height, q_data->fmt->fourcc);
+
+out:
+        mutex_unlock(&vq->vb_lock);
+        return ret;
+}
+
+static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
+                                struct v4l2_format *f)
+{
+        int ret;
+
+        ret = vidioc_try_fmt_vid_cap(file, priv, f);
+        if (ret)
+                return ret;
+
+        return vidioc_s_fmt(priv, f);
+}
+
+static int vidioc_s_fmt_vid_out(struct file *file, void *priv,
+                                struct v4l2_format *f)
+{
+        int ret;
+
+        ret = vidioc_try_fmt_vid_out(file, priv, f);
+        if (ret)
+                return ret;
+
+        return vidioc_s_fmt(priv, f);
+}
+
+static int vidioc_reqbufs(struct file *file, void *priv,
+                          struct v4l2_requestbuffers *reqbufs)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        return v4l2_m2m_reqbufs(file, ctx->m2m_ctx, reqbufs);
+}
+
+static int vidioc_querybuf(struct file *file, void *priv,
+                           struct v4l2_buffer *buf)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        return v4l2_m2m_querybuf(file, ctx->m2m_ctx, buf);
+}
+
+static int vidioc_qbuf(struct file *file, void *priv, struct v4l2_buffer *buf)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        return v4l2_m2m_qbuf(file, ctx->m2m_ctx, buf);
+}
+
+static int vidioc_dqbuf(struct file *file, void *priv, struct v4l2_buffer *buf)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        return v4l2_m2m_dqbuf(file, ctx->m2m_ctx, buf);
+}
+
+static int vidioc_streamon(struct file *file, void *priv,
+                           enum v4l2_buf_type type)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        return v4l2_m2m_streamon(file, ctx->m2m_ctx, type);
+}
+
+static int vidioc_streamoff(struct file *file, void *priv,
+                            enum v4l2_buf_type type)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        return v4l2_m2m_streamoff(file, ctx->m2m_ctx, type);
+}
+
+static int vidioc_queryctrl(struct file *file, void *priv,
+                            struct v4l2_queryctrl *qc)
+{
+        struct v4l2_queryctrl *c;
+
+        c = get_ctrl(qc->id);
+        if (!c)
+                return -EINVAL;
+
+        *qc = *c;
+        return 0;
+}
+
+static int vidioc_g_ctrl(struct file *file, void *priv,
+                         struct v4l2_control *ctrl)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        switch (ctrl->id) {
+        case V4L2_CID_TRANS_TIME_MSEC:
+                ctrl->value = ctx->transtime;
+                break;
+
+        case V4L2_CID_TRANS_NUM_BUFS:
+                ctrl->value = ctx->translen;
+                break;
+
+        default:
+                v4l2_err(&ctx->dev->v4l2_dev, "Invalid control\n");
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+static int check_ctrl_val(struct m2mtest_ctx *ctx, struct v4l2_control *ctrl)
+{
+        struct v4l2_queryctrl *c;
+
+        c = get_ctrl(ctrl->id);
+        if (!c)
+                return -EINVAL;
+
+        if (ctrl->value < c->minimum || ctrl->value > c->maximum) {
+                v4l2_err(&ctx->dev->v4l2_dev, "Value out of range\n");
+                return -ERANGE;
+        }
+
+        return 0;
+}
+
+static int vidioc_s_ctrl(struct file *file, void *priv,
+                         struct v4l2_control *ctrl)
+{
+        struct m2mtest_ctx *ctx = priv;
+        int ret = 0;
+
+        ret = check_ctrl_val(ctx, ctrl);
+        if (ret != 0)
+                return ret;
+
+        switch (ctrl->id) {
+        case V4L2_CID_TRANS_TIME_MSEC:
+                ctx->transtime = ctrl->value;
+                break;
+
+        case V4L2_CID_TRANS_NUM_BUFS:
+                ctx->translen = ctrl->value;
+                break;
+
+        default:
+                v4l2_err(&ctx->dev->v4l2_dev, "Invalid control\n");
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+
+static const struct v4l2_ioctl_ops m2mtest_ioctl_ops = {
+        .vidioc_querycap        = vidioc_querycap,
+
+        .vidioc_enum_fmt_vid_cap = vidioc_enum_fmt_vid_cap,
+        .vidioc_g_fmt_vid_cap   = vidioc_g_fmt_vid_cap,
+        .vidioc_try_fmt_vid_cap = vidioc_try_fmt_vid_cap,
+        .vidioc_s_fmt_vid_cap   = vidioc_s_fmt_vid_cap,
+
+        .vidioc_enum_fmt_vid_out = vidioc_enum_fmt_vid_out,
+        .vidioc_g_fmt_vid_out   = vidioc_g_fmt_vid_out,
+        .vidioc_try_fmt_vid_out = vidioc_try_fmt_vid_out,
+        .vidioc_s_fmt_vid_out   = vidioc_s_fmt_vid_out,
+
+        .vidioc_reqbufs         = vidioc_reqbufs,
+        .vidioc_querybuf        = vidioc_querybuf,
+
+        .vidioc_qbuf            = vidioc_qbuf,
+        .vidioc_dqbuf           = vidioc_dqbuf,
+
+        .vidioc_streamon        = vidioc_streamon,
+        .vidioc_streamoff       = vidioc_streamoff,
+
+        .vidioc_queryctrl       = vidioc_queryctrl,
+        .vidioc_g_ctrl          = vidioc_g_ctrl,
+        .vidioc_s_ctrl          = vidioc_s_ctrl,
+};
+
+
+/*
+ * Queue operations
+ */
+
+static void m2mtest_buf_release(struct videobuf_queue *vq,
+                                struct videobuf_buffer *vb)
+{
+        struct m2mtest_ctx *ctx = vq->priv_data;
+
+        dprintk(ctx->dev, "type: %d, index: %d, state: %d\n",
+                vq->type, vb->i, vb->state);
+
+        videobuf_vmalloc_free(vb);
+        vb->state = VIDEOBUF_NEEDS_INIT;
+}
+
+static int m2mtest_buf_setup(struct videobuf_queue *vq, unsigned int *count,
+                          unsigned int *size)
+{
+        struct m2mtest_ctx *ctx = vq->priv_data;
+        struct m2mtest_q_data *q_data;
+
+        q_data = get_q_data(vq->type);
+
+        *size = q_data->width * q_data->height * q_data->fmt->depth >> 3;
+        dprintk(ctx->dev, "size:%d, w/h %d/%d, depth: %d\n",
+                *size, q_data->width, q_data->height, q_data->fmt->depth);
+
+        if (0 == *count)
+                *count = MEM2MEM_DEF_NUM_BUFS;
+
+        while (*size * *count > MEM2MEM_VID_MEM_LIMIT)
+                (*count)--;
+
+        v4l2_info(&ctx->dev->v4l2_dev,
+                  "%d buffers of size %d set up.\n", *count, *size);
+
+        return 0;
+}
+
+static int m2mtest_buf_prepare(struct videobuf_queue *vq,
+                               struct videobuf_buffer *vb,
+                               enum v4l2_field field)
+{
+        struct m2mtest_ctx *ctx = vq->priv_data;
+        struct m2mtest_q_data *q_data;
+        int ret;
+
+        dprintk(ctx->dev, "type: %d, index: %d, state: %d\n",
+                vq->type, vb->i, vb->state);
+
+        q_data = get_q_data(vq->type);
+
+        if (vb->baddr) {
+                /* User-provided buffer */
+                if (vb->bsize < q_data->sizeimage) {
+                        /* Buffer too small to fit a frame */
+                        v4l2_err(&ctx->dev->v4l2_dev,
+                                 "User-provided buffer too small\n");
+                        return -EINVAL;
+                }
+        } else if (vb->state != VIDEOBUF_NEEDS_INIT
+                        && vb->bsize < q_data->sizeimage) {
+                /* We provide the buffer, but it's already been initialized
+                 * and is too small */
+                return -EINVAL;
+        }
+
+        vb->width       = q_data->width;
+        vb->height      = q_data->height;
+        vb->bytesperline = (q_data->width * q_data->fmt->depth) >> 3;
+        vb->size        = q_data->sizeimage;
+        vb->field       = field;
+
+        if (VIDEOBUF_NEEDS_INIT == vb->state) {
+                ret = videobuf_iolock(vq, vb, NULL);
+                if (ret) {
+                        v4l2_err(&ctx->dev->v4l2_dev,
+                                 "Iolock failed\n");
+                        goto fail;
+                }
+        }
+
+        vb->state = VIDEOBUF_PREPARED;
+
+        return 0;
+fail:
+        m2mtest_buf_release(vq, vb);
+        return ret;
+}
+
+static void m2mtest_buf_queue(struct videobuf_queue *vq,
+                           struct videobuf_buffer *vb)
+{
+        struct m2mtest_ctx *ctx = vq->priv_data;
+
+        v4l2_m2m_buf_queue(ctx->m2m_ctx, vq, vb);
+}
+
+static struct videobuf_queue_ops m2mtest_qops = {
+        .buf_setup      = m2mtest_buf_setup,
+        .buf_prepare    = m2mtest_buf_prepare,
+        .buf_queue      = m2mtest_buf_queue,
+        .buf_release    = m2mtest_buf_release,
+};
+
+static void queue_init(void *priv, struct videobuf_queue *vq,
+                       enum v4l2_buf_type type)
+{
+        struct m2mtest_ctx *ctx = priv;
+
+        videobuf_queue_vmalloc_init(vq, &m2mtest_qops, ctx->dev->v4l2_dev.dev,
+                                    &ctx->dev->irqlock, type, V4L2_FIELD_NONE,
+                                    sizeof(struct m2mtest_buffer), priv);
+}
+
+
+/*
+ * File operations
+ */
+static int m2mtest_open(struct file *file)
+{
+        struct m2mtest_dev *dev = video_drvdata(file);
+        struct m2mtest_ctx *ctx = NULL;
+
+        ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
+        if (!ctx)
+                return -ENOMEM;
+
+        file->private_data = ctx;
+        ctx->dev = dev;
+        ctx->translen = MEM2MEM_DEF_TRANSLEN;
+        ctx->transtime = MEM2MEM_DEF_TRANSTIME;
+        ctx->num_processed = 0;
+
+        ctx->m2m_ctx = v4l2_m2m_ctx_init(ctx, dev->m2m_dev, queue_init);
+        if (IS_ERR(ctx->m2m_ctx)) {
+                kfree(ctx);
+                return PTR_ERR(ctx->m2m_ctx);
+        }
+
+        atomic_inc(&dev->num_inst);
+
+        dprintk(dev, "Created instance %p, m2m_ctx: %p\n", ctx, ctx->m2m_ctx);
+
+        return 0;
+}
+
+static int m2mtest_release(struct file *file)
+{
+        struct m2mtest_dev *dev = video_drvdata(file);
+        struct m2mtest_ctx *ctx = file->private_data;
+
+        dprintk(dev, "Releasing instance %p\n", ctx);
+
+        v4l2_m2m_ctx_release(ctx->m2m_ctx);
+        kfree(ctx);
+
+        atomic_dec(&dev->num_inst);
+
+        return 0;
+}
+
+static unsigned int m2mtest_poll(struct file *file,
+                                 struct poll_table_struct *wait)
+{
+        struct m2mtest_ctx *ctx = (struct m2mtest_ctx *)file->private_data;
+
+        return v4l2_m2m_poll(file, ctx->m2m_ctx, wait);
+}
+
+static int m2mtest_mmap(struct file *file, struct vm_area_struct *vma)
+{
+        struct m2mtest_ctx *ctx = (struct m2mtest_ctx *)file->private_data;
+
+        return v4l2_m2m_mmap(file, ctx->m2m_ctx, vma);
+}
+
+static const struct v4l2_file_operations m2mtest_fops = {
+        .owner          = THIS_MODULE,
+        .open           = m2mtest_open,
+        .release        = m2mtest_release,
+        .poll           = m2mtest_poll,
+        .ioctl          = video_ioctl2,
+        .mmap           = m2mtest_mmap,
+};
+
+static struct video_device m2mtest_videodev = {
+        .name           = MEM2MEM_NAME,
+        .fops           = &m2mtest_fops,
+        .ioctl_ops      = &m2mtest_ioctl_ops,
+        .minor          = -1,
+        .release        = video_device_release,
+};
+
+static struct v4l2_m2m_ops m2m_ops = {
+        .device_run     = device_run,
+        .job_ready      = job_ready,
+        .job_abort      = job_abort,
+};
+
+static int m2mtest_probe(struct platform_device *pdev)
+{
+        struct m2mtest_dev *dev;
+        struct video_device *vfd;
+        int ret;
+
+        dev = kzalloc(sizeof *dev, GFP_KERNEL);
+        if (!dev)
+                return -ENOMEM;
+
+        spin_lock_init(&dev->irqlock);
+
+        ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
+        if (ret)
+                goto free_dev;
+
+        atomic_set(&dev->num_inst, 0);
+        mutex_init(&dev->dev_mutex);
+
+        vfd = video_device_alloc();
+        if (!vfd) {
+                v4l2_err(&dev->v4l2_dev, "Failed to allocate video device\n");
+                ret = -ENOMEM;
+                goto unreg_dev;
+        }
+
+        *vfd = m2mtest_videodev;
+
+        ret = video_register_device(vfd, VFL_TYPE_GRABBER, 0);
+        if (ret) {
+                v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
+                goto rel_vdev;
+        }
+
+        video_set_drvdata(vfd, dev);
+        snprintf(vfd->name, sizeof(vfd->name), "%s", m2mtest_videodev.name);
+        dev->vfd = vfd;
+        v4l2_info(&dev->v4l2_dev, MEM2MEM_TEST_MODULE_NAME
+                        "Device registered as /dev/video%d\n", vfd->num);
+
+        setup_timer(&dev->timer, device_isr, (long)dev);
+        platform_set_drvdata(pdev, dev);
+
+        dev->m2m_dev = v4l2_m2m_init(&m2m_ops);
+        if (IS_ERR(dev->m2m_dev)) {
+                v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem device\n");
+                ret = PTR_ERR(dev->m2m_dev);
+                goto err_m2m;
+        }
+
+        return 0;
+
+err_m2m:
+        video_unregister_device(dev->vfd);
+rel_vdev:
+        video_device_release(vfd);
+unreg_dev:
+        v4l2_device_unregister(&dev->v4l2_dev);
+free_dev:
+        kfree(dev);
+
+        return ret;
+}
+
+static int m2mtest_remove(struct platform_device *pdev)
+{
+        struct m2mtest_dev *dev =
+                (struct m2mtest_dev *)platform_get_drvdata(pdev);
+
+        v4l2_info(&dev->v4l2_dev, "Removing " MEM2MEM_TEST_MODULE_NAME);
+        v4l2_m2m_release(dev->m2m_dev);
+        del_timer_sync(&dev->timer);
+        video_unregister_device(dev->vfd);
+        v4l2_device_unregister(&dev->v4l2_dev);
+        kfree(dev);
+
+        return 0;
+}
+
+static struct platform_driver m2mtest_pdrv = {
+        .probe          = m2mtest_probe,
+        .remove         = m2mtest_remove,
+        .driver         = {
+                .name   = MEM2MEM_NAME,
+                .owner  = THIS_MODULE,
+        },
+};
+
+static void __exit m2mtest_exit(void)
+{
+        platform_driver_unregister(&m2mtest_pdrv);
+        platform_device_unregister(&m2mtest_pdev);
+}
+
+static int __init m2mtest_init(void)
+{
+        int ret;
+
+        ret = platform_device_register(&m2mtest_pdev);
+        if (ret)
+                return ret;
+
+        ret = platform_driver_register(&m2mtest_pdrv);
+        if (ret)
+                platform_device_unregister(&m2mtest_pdev);
+
+        return 0;
+}
+
+module_init(m2mtest_init);
+module_exit(m2mtest_exit);
+