sh_mobile_ceu_camera.c

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/*
 * V4L2 Driver for SuperH Mobile CEU interface
 *
 * Copyright (C) 2008 Magnus Damm
 *
 * Based on V4L2 Driver for PXA camera host - "pxa_camera.c",
 *
 * Copyright (C) 2006, Sascha Hauer, Pengutronix
 * Copyright (C) 2008, Guennadi Liakhovetski <[email protected]>
 *
 * 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/init.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/moduleparam.h>
#include <linux/time.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/videodev2.h>
#include <linux/pm_runtime.h>
#include <linux/sched.h>

#include <media/v4l2-common.h>
#include <media/v4l2-dev.h>
#include <media/soc_camera.h>
#include <media/sh_mobile_ceu.h>
#include <media/sh_mobile_csi2.h>
#include <media/videobuf2-dma-contig.h>
#include <media/v4l2-mediabus.h>
#include <media/soc_mediabus.h>

/* register offsets for sh7722 / sh7723 */

#define CAPSR  0x00 /* Capture start register */
#define CAPCR  0x04 /* Capture control register */
#define CAMCR  0x08 /* Capture interface control register */
#define CMCYR  0x0c /* Capture interface cycle  register */
#define CAMOR  0x10 /* Capture interface offset register */
#define CAPWR  0x14 /* Capture interface width register */
#define CAIFR  0x18 /* Capture interface input format register */
#define CSTCR  0x20 /* Camera strobe control register (<= sh7722) */
#define CSECR  0x24 /* Camera strobe emission count register (<= sh7722) */
#define CRCNTR 0x28 /* CEU register control register */
#define CRCMPR 0x2c /* CEU register forcible control register */
#define CFLCR  0x30 /* Capture filter control register */
#define CFSZR  0x34 /* Capture filter size clip register */
#define CDWDR  0x38 /* Capture destination width register */
#define CDAYR  0x3c /* Capture data address Y register */
#define CDACR  0x40 /* Capture data address C register */
#define CDBYR  0x44 /* Capture data bottom-field address Y register */
#define CDBCR  0x48 /* Capture data bottom-field address C register */
#define CBDSR  0x4c /* Capture bundle destination size register */
#define CFWCR  0x5c /* Firewall operation control register */
#define CLFCR  0x60 /* Capture low-pass filter control register */
#define CDOCR  0x64 /* Capture data output control register */
#define CDDCR  0x68 /* Capture data complexity level register */
#define CDDAR  0x6c /* Capture data complexity level address register */
#define CEIER  0x70 /* Capture event interrupt enable register */
#define CETCR  0x74 /* Capture event flag clear register */
#define CSTSR  0x7c /* Capture status register */
#define CSRTR  0x80 /* Capture software reset register */
#define CDSSR  0x84 /* Capture data size register */
#define CDAYR2 0x90 /* Capture data address Y register 2 */
#define CDACR2 0x94 /* Capture data address C register 2 */
#define CDBYR2 0x98 /* Capture data bottom-field address Y register 2 */
#define CDBCR2 0x9c /* Capture data bottom-field address C register 2 */

#undef DEBUG_GEOMETRY
#ifdef DEBUG_GEOMETRY
#define dev_geo dev_info
#else
#define dev_geo dev_dbg
#endif

/* per video frame buffer */
struct sh_mobile_ceu_buffer {
    struct vb2_buffer vb; /* v4l buffer must be first */
    struct list_head queue;
};

struct sh_mobile_ceu_dev {
    struct soc_camera_host ici;
    struct soc_camera_device *icd;
    struct platform_device *csi2_pdev;

    unsigned int irq;
    void __iomem *base;
    size_t video_limit;
    size_t buf_total;

    spinlock_t lock;        /* Protects video buffer lists */
    struct list_head capture;
    struct vb2_buffer *active;
    struct vb2_alloc_ctx *alloc_ctx;

    struct sh_mobile_ceu_info *pdata;
    struct completion complete;

    u32 cflcr;

    /* static max sizes either from platform data or default */
    int max_width;
    int max_height;

    enum v4l2_field field;
    int sequence;

    unsigned int image_mode:1;
    unsigned int is_16bit:1;
    unsigned int frozen:1;
};

struct sh_mobile_ceu_cam {
    /* CEU offsets within the camera output, before the CEU scaler */
    unsigned int ceu_left;
    unsigned int ceu_top;
    /* Client output, as seen by the CEU */
    unsigned int width;
    unsigned int height;
    /*
     * User window from S_CROP / G_CROP, produced by client cropping and
     * scaling, CEU scaling and CEU cropping, mapped back onto the client
     * input window
     */
    struct v4l2_rect subrect;
    /* Camera cropping rectangle */
    struct v4l2_rect rect;
    const struct soc_mbus_pixelfmt *extra_fmt;
    enum v4l2_mbus_pixelcode code;
};

static struct sh_mobile_ceu_buffer *to_ceu_vb(struct vb2_buffer *vb)
{
    return container_of(vb, struct sh_mobile_ceu_buffer, vb);
}

static void ceu_write(struct sh_mobile_ceu_dev *priv,
              unsigned long reg_offs, u32 data)
{
    iowrite32(data, priv->base + reg_offs);
}

static u32 ceu_read(struct sh_mobile_ceu_dev *priv, unsigned long reg_offs)
{
    return ioread32(priv->base + reg_offs);
}

static int sh_mobile_ceu_soft_reset(struct sh_mobile_ceu_dev *pcdev)
{
    int i, success = 0;
    struct soc_camera_device *icd = pcdev->icd;

    ceu_write(pcdev, CAPSR, 1 << 16); /* reset */

    /* wait CSTSR.CPTON bit */
    for (i = 0; i < 1000; i++) {
        if (!(ceu_read(pcdev, CSTSR) & 1)) {
            success++;
            break;
        }
        udelay(1);
    }

    /* wait CAPSR.CPKIL bit */
    for (i = 0; i < 1000; i++) {
        if (!(ceu_read(pcdev, CAPSR) & (1 << 16))) {
            success++;
            break;
        }
        udelay(1);
    }


    if (2 != success) {
        dev_warn(icd->pdev, "soft reset time out\n");
        return -EIO;
    }

    return 0;
}

/*
 *  Videobuf operations
 */

/*
 * .queue_setup() is called to check, whether the driver can accept the
 *        requested number of buffers and to fill in plane sizes
 *        for the current frame format if required
 */
static int sh_mobile_ceu_videobuf_setup(struct vb2_queue *vq,
            const struct v4l2_format *fmt,
            unsigned int *count, unsigned int *num_planes,
            unsigned int sizes[], void *alloc_ctxs[])
{
    struct soc_camera_device *icd = container_of(vq, struct soc_camera_device, vb2_vidq);
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;

    if (fmt) {
        const struct soc_camera_format_xlate *xlate = soc_camera_xlate_by_fourcc(icd,
                                fmt->fmt.pix.pixelformat);
        unsigned int bytes_per_line;
        int ret;

        if (!xlate)
            return -EINVAL;

        ret = soc_mbus_bytes_per_line(fmt->fmt.pix.width,
                          xlate->host_fmt);
        if (ret < 0)
            return ret;

        bytes_per_line = max_t(u32, fmt->fmt.pix.bytesperline, ret);

        ret = soc_mbus_image_size(xlate->host_fmt, bytes_per_line,
                      fmt->fmt.pix.height);
        if (ret < 0)
            return ret;

        sizes[0] = max_t(u32, fmt->fmt.pix.sizeimage, ret);
    } else {
        /* Called from VIDIOC_REQBUFS or in compatibility mode */
        sizes[0] = icd->sizeimage;
    }

    alloc_ctxs[0] = pcdev->alloc_ctx;

    if (!vq->num_buffers)
        pcdev->sequence = 0;

    if (!*count)
        *count = 2;

    /* If *num_planes != 0, we have already verified *count. */
    if (pcdev->video_limit && !*num_planes) {
        size_t size = PAGE_ALIGN(sizes[0]) * *count;

        if (size + pcdev->buf_total > pcdev->video_limit)
            *count = (pcdev->video_limit - pcdev->buf_total) /
                PAGE_ALIGN(sizes[0]);
    }

    *num_planes = 1;

    dev_dbg(icd->parent, "count=%d, size=%u\n", *count, sizes[0]);

    return 0;
}

#define CEU_CETCR_MAGIC 0x0317f313 /* acknowledge magical interrupt sources */
#define CEU_CETCR_IGRW (1 << 4) /* prohibited register access interrupt bit */
#define CEU_CEIER_CPEIE (1 << 0) /* one-frame capture end interrupt */
#define CEU_CEIER_VBP   (1 << 20) /* vbp error */
#define CEU_CAPCR_CTNCP (1 << 16) /* continuous capture mode (if set) */
#define CEU_CEIER_MASK (CEU_CEIER_CPEIE | CEU_CEIER_VBP)


/*
 * return value doesn't reflex the success/failure to queue the new buffer,
 * but rather the status of the previous buffer.
 */
static int sh_mobile_ceu_capture(struct sh_mobile_ceu_dev *pcdev)
{
    struct soc_camera_device *icd = pcdev->icd;
    dma_addr_t phys_addr_top, phys_addr_bottom;
    unsigned long top1, top2;
    unsigned long bottom1, bottom2;
    u32 status;
    bool planar;
    int ret = 0;

    /*
     * The hardware is _very_ picky about this sequence. Especially
     * the CEU_CETCR_MAGIC value. It seems like we need to acknowledge
     * several not-so-well documented interrupt sources in CETCR.
     */
    ceu_write(pcdev, CEIER, ceu_read(pcdev, CEIER) & ~CEU_CEIER_MASK);
    status = ceu_read(pcdev, CETCR);
    ceu_write(pcdev, CETCR, ~status & CEU_CETCR_MAGIC);
    if (!pcdev->frozen)
        ceu_write(pcdev, CEIER, ceu_read(pcdev, CEIER) | CEU_CEIER_MASK);
    ceu_write(pcdev, CAPCR, ceu_read(pcdev, CAPCR) & ~CEU_CAPCR_CTNCP);
    ceu_write(pcdev, CETCR, CEU_CETCR_MAGIC ^ CEU_CETCR_IGRW);

    /*
     * When a VBP interrupt occurs, a capture end interrupt does not occur
     * and the image of that frame is not captured correctly. So, soft reset
     * is needed here.
     */
    if (status & CEU_CEIER_VBP) {
        sh_mobile_ceu_soft_reset(pcdev);
        ret = -EIO;
    }

    if (pcdev->frozen) {
        complete(&pcdev->complete);
        return ret;
    }

    if (!pcdev->active)
        return ret;

    if (V4L2_FIELD_INTERLACED_BT == pcdev->field) {
        top1    = CDBYR;
        top2    = CDBCR;
        bottom1 = CDAYR;
        bottom2 = CDACR;
    } else {
        top1    = CDAYR;
        top2    = CDACR;
        bottom1 = CDBYR;
        bottom2 = CDBCR;
    }

    phys_addr_top = vb2_dma_contig_plane_dma_addr(pcdev->active, 0);

    switch (icd->current_fmt->host_fmt->fourcc) {
    case V4L2_PIX_FMT_NV12:
    case V4L2_PIX_FMT_NV21:
    case V4L2_PIX_FMT_NV16:
    case V4L2_PIX_FMT_NV61:
        planar = true;
        break;
    default:
        planar = false;
    }

    ceu_write(pcdev, top1, phys_addr_top);
    if (V4L2_FIELD_NONE != pcdev->field) {
        phys_addr_bottom = phys_addr_top + icd->bytesperline;
        ceu_write(pcdev, bottom1, phys_addr_bottom);
    }

    if (planar) {
        phys_addr_top += icd->bytesperline * icd->user_height;
        ceu_write(pcdev, top2, phys_addr_top);
        if (V4L2_FIELD_NONE != pcdev->field) {
            phys_addr_bottom = phys_addr_top + icd->bytesperline;
            ceu_write(pcdev, bottom2, phys_addr_bottom);
        }
    }

    ceu_write(pcdev, CAPSR, 0x1); /* start capture */

    return ret;
}

static int sh_mobile_ceu_videobuf_prepare(struct vb2_buffer *vb)
{
    struct sh_mobile_ceu_buffer *buf = to_ceu_vb(vb);

    /* Added list head initialization on alloc */
    WARN(!list_empty(&buf->queue), "Buffer %p on queue!\n", vb);

    return 0;
}

static void sh_mobile_ceu_videobuf_queue(struct vb2_buffer *vb)
{
    struct soc_camera_device *icd = container_of(vb->vb2_queue, struct soc_camera_device, vb2_vidq);
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    struct sh_mobile_ceu_buffer *buf = to_ceu_vb(vb);
    unsigned long size;

    size = icd->sizeimage;

    if (vb2_plane_size(vb, 0) < size) {
        dev_err(icd->parent, "Buffer #%d too small (%lu < %lu)\n",
            vb->v4l2_buf.index, vb2_plane_size(vb, 0), size);
        goto error;
    }

    vb2_set_plane_payload(vb, 0, size);

    dev_dbg(icd->parent, "%s (vb=0x%p) 0x%p %lu\n", __func__,
        vb, vb2_plane_vaddr(vb, 0), vb2_get_plane_payload(vb, 0));

#ifdef DEBUG
    /*
     * This can be useful if you want to see if we actually fill
     * the buffer with something
     */
    if (vb2_plane_vaddr(vb, 0))
        memset(vb2_plane_vaddr(vb, 0), 0xaa, vb2_get_plane_payload(vb, 0));
#endif

    spin_lock_irq(&pcdev->lock);
    list_add_tail(&buf->queue, &pcdev->capture);

    if (!pcdev->active) {
        /*
         * Because there were no active buffer at this moment,
         * we are not interested in the return value of
         * sh_mobile_ceu_capture here.
         */
        pcdev->active = vb;
        sh_mobile_ceu_capture(pcdev);
    }
    spin_unlock_irq(&pcdev->lock);

    return;

error:
    vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
}

static void sh_mobile_ceu_videobuf_release(struct vb2_buffer *vb)
{
    struct soc_camera_device *icd = container_of(vb->vb2_queue, struct soc_camera_device, vb2_vidq);
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_buffer *buf = to_ceu_vb(vb);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;

    spin_lock_irq(&pcdev->lock);

    if (pcdev->active == vb) {
        /* disable capture (release DMA buffer), reset */
        ceu_write(pcdev, CAPSR, 1 << 16);
        pcdev->active = NULL;
    }

    /*
     * Doesn't hurt also if the list is empty, but it hurts, if queuing the
     * buffer failed, and .buf_init() hasn't been called
     */
    if (buf->queue.next)
        list_del_init(&buf->queue);

    pcdev->buf_total -= PAGE_ALIGN(vb2_plane_size(vb, 0));
    dev_dbg(icd->parent, "%s() %zu bytes buffers\n", __func__,
        pcdev->buf_total);

    spin_unlock_irq(&pcdev->lock);
}

static int sh_mobile_ceu_videobuf_init(struct vb2_buffer *vb)
{
    struct soc_camera_device *icd = container_of(vb->vb2_queue, struct soc_camera_device, vb2_vidq);
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;

    pcdev->buf_total += PAGE_ALIGN(vb2_plane_size(vb, 0));
    dev_dbg(icd->parent, "%s() %zu bytes buffers\n", __func__,
        pcdev->buf_total);

    /* This is for locking debugging only */
    INIT_LIST_HEAD(&to_ceu_vb(vb)->queue);
    return 0;
}

static int sh_mobile_ceu_stop_streaming(struct vb2_queue *q)
{
    struct soc_camera_device *icd = container_of(q, struct soc_camera_device, vb2_vidq);
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    struct list_head *buf_head, *tmp;

    spin_lock_irq(&pcdev->lock);

    pcdev->active = NULL;

    list_for_each_safe(buf_head, tmp, &pcdev->capture)
        list_del_init(buf_head);

    spin_unlock_irq(&pcdev->lock);

    return sh_mobile_ceu_soft_reset(pcdev);
}

static struct vb2_ops sh_mobile_ceu_videobuf_ops = {
    .queue_setup    = sh_mobile_ceu_videobuf_setup,
    .buf_prepare    = sh_mobile_ceu_videobuf_prepare,
    .buf_queue  = sh_mobile_ceu_videobuf_queue,
    .buf_cleanup    = sh_mobile_ceu_videobuf_release,
    .buf_init   = sh_mobile_ceu_videobuf_init,
    .wait_prepare   = soc_camera_unlock,
    .wait_finish    = soc_camera_lock,
    .stop_streaming = sh_mobile_ceu_stop_streaming,
};

static irqreturn_t sh_mobile_ceu_irq(int irq, void *data)
{
    struct sh_mobile_ceu_dev *pcdev = data;
    struct vb2_buffer *vb;
    int ret;

    spin_lock(&pcdev->lock);

    vb = pcdev->active;
    if (!vb)
        /* Stale interrupt from a released buffer */
        goto out;

    list_del_init(&to_ceu_vb(vb)->queue);

    if (!list_empty(&pcdev->capture))
        pcdev->active = &list_entry(pcdev->capture.next,
                        struct sh_mobile_ceu_buffer, queue)->vb;
    else
        pcdev->active = NULL;

    ret = sh_mobile_ceu_capture(pcdev);
    do_gettimeofday(&vb->v4l2_buf.timestamp);
    if (!ret) {
        vb->v4l2_buf.field = pcdev->field;
        vb->v4l2_buf.sequence = pcdev->sequence++;
    }
    vb2_buffer_done(vb, ret < 0 ? VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);

out:
    spin_unlock(&pcdev->lock);

    return IRQ_HANDLED;
}

static struct v4l2_subdev *find_csi2(struct sh_mobile_ceu_dev *pcdev)
{
    struct v4l2_subdev *sd;

    if (!pcdev->csi2_pdev)
        return NULL;

    v4l2_device_for_each_subdev(sd, &pcdev->ici.v4l2_dev)
        if (&pcdev->csi2_pdev->dev == v4l2_get_subdevdata(sd))
            return sd;

    return NULL;
}

/* Called with .video_lock held */
static int sh_mobile_ceu_add_device(struct soc_camera_device *icd)
{
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    struct v4l2_subdev *csi2_sd;
    int ret;

    if (pcdev->icd)
        return -EBUSY;

    dev_info(icd->parent,
         "SuperH Mobile CEU driver attached to camera %d\n",
         icd->devnum);

    pm_runtime_get_sync(ici->v4l2_dev.dev);

    pcdev->buf_total = 0;

    ret = sh_mobile_ceu_soft_reset(pcdev);

    csi2_sd = find_csi2(pcdev);
    if (csi2_sd) {
        csi2_sd->grp_id = soc_camera_grp_id(icd);
        v4l2_set_subdev_hostdata(csi2_sd, icd);
    }

    ret = v4l2_subdev_call(csi2_sd, core, s_power, 1);
    if (ret < 0 && ret != -ENOIOCTLCMD && ret != -ENODEV) {
        pm_runtime_put_sync(ici->v4l2_dev.dev);
        return ret;
    }

    /*
     * -ENODEV is special: either csi2_sd == NULL or the CSI-2 driver
     * has not found this soc-camera device among its clients
     */
    if (ret == -ENODEV && csi2_sd)
        csi2_sd->grp_id = 0;
    pcdev->icd = icd;

    return 0;
}

/* Called with .video_lock held */
static void sh_mobile_ceu_remove_device(struct soc_camera_device *icd)
{
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    struct v4l2_subdev *csi2_sd = find_csi2(pcdev);

    BUG_ON(icd != pcdev->icd);

    v4l2_subdev_call(csi2_sd, core, s_power, 0);
    if (csi2_sd)
        csi2_sd->grp_id = 0;
    /* disable capture, disable interrupts */
    ceu_write(pcdev, CEIER, 0);
    sh_mobile_ceu_soft_reset(pcdev);

    /* make sure active buffer is canceled */
    spin_lock_irq(&pcdev->lock);
    if (pcdev->active) {
        list_del_init(&to_ceu_vb(pcdev->active)->queue);
        vb2_buffer_done(pcdev->active, VB2_BUF_STATE_ERROR);
        pcdev->active = NULL;
    }
    spin_unlock_irq(&pcdev->lock);

    pm_runtime_put_sync(ici->v4l2_dev.dev);

    dev_info(icd->parent,
         "SuperH Mobile CEU driver detached from camera %d\n",
         icd->devnum);

    pcdev->icd = NULL;
}

/*
 * See chapter 29.4.12 "Capture Filter Control Register (CFLCR)"
 * in SH7722 Hardware Manual
 */
static unsigned int size_dst(unsigned int src, unsigned int scale)
{
    unsigned int mant_pre = scale >> 12;
    if (!src || !scale)
        return src;
    return ((mant_pre + 2 * (src - 1)) / (2 * mant_pre) - 1) *
        mant_pre * 4096 / scale + 1;
}

static u16 calc_scale(unsigned int src, unsigned int *dst)
{
    u16 scale;

    if (src == *dst)
        return 0;

    scale = (src * 4096 / *dst) & ~7;

    while (scale > 4096 && size_dst(src, scale) < *dst)
        scale -= 8;

    *dst = size_dst(src, scale);

    return scale;
}

/* rect is guaranteed to not exceed the scaled camera rectangle */
static void sh_mobile_ceu_set_rect(struct soc_camera_device *icd)
{
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_cam *cam = icd->host_priv;
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    unsigned int height, width, cdwdr_width, in_width, in_height;
    unsigned int left_offset, top_offset;
    u32 camor;

    dev_geo(icd->parent, "Crop %ux%u@%u:%u\n",
        icd->user_width, icd->user_height, cam->ceu_left, cam->ceu_top);

    left_offset = cam->ceu_left;
    top_offset  = cam->ceu_top;

    WARN_ON(icd->user_width & 3 || icd->user_height & 3);

    width = icd->user_width;

    if (pcdev->image_mode) {
        in_width = cam->width;
        if (!pcdev->is_16bit) {
            in_width *= 2;
            left_offset *= 2;
        }
    } else {
        unsigned int w_factor;

        switch (icd->current_fmt->host_fmt->packing) {
        case SOC_MBUS_PACKING_2X8_PADHI:
            w_factor = 2;
            break;
        default:
            w_factor = 1;
        }

        in_width = cam->width * w_factor;
        left_offset *= w_factor;
    }

    cdwdr_width = icd->bytesperline;

    height = icd->user_height;
    in_height = cam->height;
    if (V4L2_FIELD_NONE != pcdev->field) {
        height = (height / 2) & ~3;
        in_height /= 2;
        top_offset /= 2;
        cdwdr_width *= 2;
    }

    /* CSI2 special configuration */
    if (pcdev->pdata->csi2) {
        in_width = ((in_width - 2) * 2);
        left_offset *= 2;
    }

    /* Set CAMOR, CAPWR, CFSZR, take care of CDWDR */
    camor = left_offset | (top_offset << 16);

    dev_geo(icd->parent,
        "CAMOR 0x%x, CAPWR 0x%x, CFSZR 0x%x, CDWDR 0x%x\n", camor,
        (in_height << 16) | in_width, (height << 16) | width,
        cdwdr_width);

    ceu_write(pcdev, CAMOR, camor);
    ceu_write(pcdev, CAPWR, (in_height << 16) | in_width);
    /* CFSZR clipping is applied _after_ the scaling filter (CFLCR) */
    ceu_write(pcdev, CFSZR, (height << 16) | width);
    ceu_write(pcdev, CDWDR, cdwdr_width);
}

static u32 capture_save_reset(struct sh_mobile_ceu_dev *pcdev)
{
    u32 capsr = ceu_read(pcdev, CAPSR);
    ceu_write(pcdev, CAPSR, 1 << 16); /* reset, stop capture */
    return capsr;
}

static void capture_restore(struct sh_mobile_ceu_dev *pcdev, u32 capsr)
{
    unsigned long timeout = jiffies + 10 * HZ;

    /*
     * Wait until the end of the current frame. It can take a long time,
     * but if it has been aborted by a CAPSR reset, it shoule exit sooner.
     */
    while ((ceu_read(pcdev, CSTSR) & 1) && time_before(jiffies, timeout))
        msleep(1);

    if (time_after(jiffies, timeout)) {
        dev_err(pcdev->ici.v4l2_dev.dev,
            "Timeout waiting for frame end! Interface problem?\n");
        return;
    }

    /* Wait until reset clears, this shall not hang... */
    while (ceu_read(pcdev, CAPSR) & (1 << 16))
        udelay(10);

    /* Anything to restore? */
    if (capsr & ~(1 << 16))
        ceu_write(pcdev, CAPSR, capsr);
}

/* Find the bus subdevice driver, e.g., CSI2 */
static struct v4l2_subdev *find_bus_subdev(struct sh_mobile_ceu_dev *pcdev,
                       struct soc_camera_device *icd)
{
    if (pcdev->csi2_pdev) {
        struct v4l2_subdev *csi2_sd = find_csi2(pcdev);
        if (csi2_sd && csi2_sd->grp_id == soc_camera_grp_id(icd))
            return csi2_sd;
    }

    return soc_camera_to_subdev(icd);
}

#define CEU_BUS_FLAGS (V4L2_MBUS_MASTER |   \
        V4L2_MBUS_PCLK_SAMPLE_RISING |  \
        V4L2_MBUS_HSYNC_ACTIVE_HIGH |   \
        V4L2_MBUS_HSYNC_ACTIVE_LOW |    \
        V4L2_MBUS_VSYNC_ACTIVE_HIGH |   \
        V4L2_MBUS_VSYNC_ACTIVE_LOW |    \
        V4L2_MBUS_DATA_ACTIVE_HIGH)

/* Capture is not running, no interrupts, no locking needed */
static int sh_mobile_ceu_set_bus_param(struct soc_camera_device *icd)
{
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    struct v4l2_subdev *sd = find_bus_subdev(pcdev, icd);
    struct sh_mobile_ceu_cam *cam = icd->host_priv;
    struct v4l2_mbus_config cfg = {.type = V4L2_MBUS_PARALLEL,};
    unsigned long value, common_flags = CEU_BUS_FLAGS;
    u32 capsr = capture_save_reset(pcdev);
    unsigned int yuv_lineskip;
    int ret;

    /*
     * If the client doesn't implement g_mbus_config, we just use our
     * platform data
     */
    ret = v4l2_subdev_call(sd, video, g_mbus_config, &cfg);
    if (!ret) {
        common_flags = soc_mbus_config_compatible(&cfg,
                              common_flags);
        if (!common_flags)
            return -EINVAL;
    } else if (ret != -ENOIOCTLCMD) {
        return ret;
    }

    /* Make choises, based on platform preferences */
    if ((common_flags & V4L2_MBUS_HSYNC_ACTIVE_HIGH) &&
        (common_flags & V4L2_MBUS_HSYNC_ACTIVE_LOW)) {
        if (pcdev->pdata->flags & SH_CEU_FLAG_HSYNC_LOW)
            common_flags &= ~V4L2_MBUS_HSYNC_ACTIVE_HIGH;
        else
            common_flags &= ~V4L2_MBUS_HSYNC_ACTIVE_LOW;
    }

    if ((common_flags & V4L2_MBUS_VSYNC_ACTIVE_HIGH) &&
        (common_flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)) {
        if (pcdev->pdata->flags & SH_CEU_FLAG_VSYNC_LOW)
            common_flags &= ~V4L2_MBUS_VSYNC_ACTIVE_HIGH;
        else
            common_flags &= ~V4L2_MBUS_VSYNC_ACTIVE_LOW;
    }

    cfg.flags = common_flags;
    ret = v4l2_subdev_call(sd, video, s_mbus_config, &cfg);
    if (ret < 0 && ret != -ENOIOCTLCMD)
        return ret;

    if (icd->current_fmt->host_fmt->bits_per_sample > 8)
        pcdev->is_16bit = 1;
    else
        pcdev->is_16bit = 0;

    ceu_write(pcdev, CRCNTR, 0);
    ceu_write(pcdev, CRCMPR, 0);

    value = 0x00000010; /* data fetch by default */
    yuv_lineskip = 0x10;

    switch (icd->current_fmt->host_fmt->fourcc) {
    case V4L2_PIX_FMT_NV12:
    case V4L2_PIX_FMT_NV21:
        /* convert 4:2:2 -> 4:2:0 */
        yuv_lineskip = 0; /* skip for NV12/21, no skip for NV16/61 */
        /* fall-through */
    case V4L2_PIX_FMT_NV16:
    case V4L2_PIX_FMT_NV61:
        switch (cam->code) {
        case V4L2_MBUS_FMT_UYVY8_2X8:
            value = 0x00000000; /* Cb0, Y0, Cr0, Y1 */
            break;
        case V4L2_MBUS_FMT_VYUY8_2X8:
            value = 0x00000100; /* Cr0, Y0, Cb0, Y1 */
            break;
        case V4L2_MBUS_FMT_YUYV8_2X8:
            value = 0x00000200; /* Y0, Cb0, Y1, Cr0 */
            break;
        case V4L2_MBUS_FMT_YVYU8_2X8:
            value = 0x00000300; /* Y0, Cr0, Y1, Cb0 */
            break;
        default:
            BUG();
        }
    }

    if (icd->current_fmt->host_fmt->fourcc == V4L2_PIX_FMT_NV21 ||
        icd->current_fmt->host_fmt->fourcc == V4L2_PIX_FMT_NV61)
        value ^= 0x00000100; /* swap U, V to change from NV1x->NVx1 */

    value |= common_flags & V4L2_MBUS_VSYNC_ACTIVE_LOW ? 1 << 1 : 0;
    value |= common_flags & V4L2_MBUS_HSYNC_ACTIVE_LOW ? 1 << 0 : 0;

    if (pcdev->pdata->csi2) /* CSI2 mode */
        value |= 3 << 12;
    else if (pcdev->is_16bit)
        value |= 1 << 12;
    else if (pcdev->pdata->flags & SH_CEU_FLAG_LOWER_8BIT)
        value |= 2 << 12;

    ceu_write(pcdev, CAMCR, value);

    ceu_write(pcdev, CAPCR, 0x00300000);

    switch (pcdev->field) {
    case V4L2_FIELD_INTERLACED_TB:
        value = 0x101;
        break;
    case V4L2_FIELD_INTERLACED_BT:
        value = 0x102;
        break;
    default:
        value = 0;
        break;
    }
    ceu_write(pcdev, CAIFR, value);

    sh_mobile_ceu_set_rect(icd);
    mdelay(1);

    dev_geo(icd->parent, "CFLCR 0x%x\n", pcdev->cflcr);
    ceu_write(pcdev, CFLCR, pcdev->cflcr);

    /*
     * A few words about byte order (observed in Big Endian mode)
     *
     * In data fetch mode bytes are received in chunks of 8 bytes.
     * D0, D1, D2, D3, D4, D5, D6, D7 (D0 received first)
     *
     * The data is however by default written to memory in reverse order:
     * D7, D6, D5, D4, D3, D2, D1, D0 (D7 written to lowest byte)
     *
     * The lowest three bits of CDOCR allows us to do swapping,
     * using 7 we swap the data bytes to match the incoming order:
     * D0, D1, D2, D3, D4, D5, D6, D7
     */
    value = 0x00000007 | yuv_lineskip;

    ceu_write(pcdev, CDOCR, value);
    ceu_write(pcdev, CFWCR, 0); /* keep "datafetch firewall" disabled */

    capture_restore(pcdev, capsr);

    /* not in bundle mode: skip CBDSR, CDAYR2, CDACR2, CDBYR2, CDBCR2 */
    return 0;
}

static int sh_mobile_ceu_try_bus_param(struct soc_camera_device *icd,
                       unsigned char buswidth)
{
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    struct v4l2_subdev *sd = find_bus_subdev(pcdev, icd);
    unsigned long common_flags = CEU_BUS_FLAGS;
    struct v4l2_mbus_config cfg = {.type = V4L2_MBUS_PARALLEL,};
    int ret;

    ret = v4l2_subdev_call(sd, video, g_mbus_config, &cfg);
    if (!ret)
        common_flags = soc_mbus_config_compatible(&cfg,
                              common_flags);
    else if (ret != -ENOIOCTLCMD)
        return ret;

    if (!common_flags || buswidth > 16)
        return -EINVAL;

    return 0;
}

static const struct soc_mbus_pixelfmt sh_mobile_ceu_formats[] = {
    {
        .fourcc         = V4L2_PIX_FMT_NV12,
        .name           = "NV12",
        .bits_per_sample    = 8,
        .packing        = SOC_MBUS_PACKING_1_5X8,
        .order          = SOC_MBUS_ORDER_LE,
        .layout         = SOC_MBUS_LAYOUT_PLANAR_2Y_C,
    }, {
        .fourcc         = V4L2_PIX_FMT_NV21,
        .name           = "NV21",
        .bits_per_sample    = 8,
        .packing        = SOC_MBUS_PACKING_1_5X8,
        .order          = SOC_MBUS_ORDER_LE,
        .layout         = SOC_MBUS_LAYOUT_PLANAR_2Y_C,
    }, {
        .fourcc         = V4L2_PIX_FMT_NV16,
        .name           = "NV16",
        .bits_per_sample    = 8,
        .packing        = SOC_MBUS_PACKING_2X8_PADHI,
        .order          = SOC_MBUS_ORDER_LE,
        .layout         = SOC_MBUS_LAYOUT_PLANAR_Y_C,
    }, {
        .fourcc         = V4L2_PIX_FMT_NV61,
        .name           = "NV61",
        .bits_per_sample    = 8,
        .packing        = SOC_MBUS_PACKING_2X8_PADHI,
        .order          = SOC_MBUS_ORDER_LE,
        .layout         = SOC_MBUS_LAYOUT_PLANAR_Y_C,
    },
};

/* This will be corrected as we get more formats */
static bool sh_mobile_ceu_packing_supported(const struct soc_mbus_pixelfmt *fmt)
{
    return  fmt->packing == SOC_MBUS_PACKING_NONE ||
        (fmt->bits_per_sample == 8 &&
         fmt->packing == SOC_MBUS_PACKING_1_5X8) ||
        (fmt->bits_per_sample == 8 &&
         fmt->packing == SOC_MBUS_PACKING_2X8_PADHI) ||
        (fmt->bits_per_sample > 8 &&
         fmt->packing == SOC_MBUS_PACKING_EXTEND16);
}

static int client_g_rect(struct v4l2_subdev *sd, struct v4l2_rect *rect);

static struct soc_camera_device *ctrl_to_icd(struct v4l2_ctrl *ctrl)
{
    return container_of(ctrl->handler, struct soc_camera_device,
                            ctrl_handler);
}

static int sh_mobile_ceu_s_ctrl(struct v4l2_ctrl *ctrl)
{
    struct soc_camera_device *icd = ctrl_to_icd(ctrl);
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;

    switch (ctrl->id) {
    case V4L2_CID_SHARPNESS:
        switch (icd->current_fmt->host_fmt->fourcc) {
        case V4L2_PIX_FMT_NV12:
        case V4L2_PIX_FMT_NV21:
        case V4L2_PIX_FMT_NV16:
        case V4L2_PIX_FMT_NV61:
            ceu_write(pcdev, CLFCR, !ctrl->val);
            return 0;
        }
        break;
    }

    return -EINVAL;
}

static const struct v4l2_ctrl_ops sh_mobile_ceu_ctrl_ops = {
    .s_ctrl = sh_mobile_ceu_s_ctrl,
};

static int sh_mobile_ceu_get_formats(struct soc_camera_device *icd, unsigned int idx,
                     struct soc_camera_format_xlate *xlate)
{
    struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
    struct device *dev = icd->parent;
    struct soc_camera_host *ici = to_soc_camera_host(dev);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    int ret, k, n;
    int formats = 0;
    struct sh_mobile_ceu_cam *cam;
    enum v4l2_mbus_pixelcode code;
    const struct soc_mbus_pixelfmt *fmt;

    ret = v4l2_subdev_call(sd, video, enum_mbus_fmt, idx, &code);
    if (ret < 0)
        /* No more formats */
        return 0;

    fmt = soc_mbus_get_fmtdesc(code);
    if (!fmt) {
        dev_warn(dev, "unsupported format code #%u: %d\n", idx, code);
        return 0;
    }

    if (!pcdev->pdata->csi2) {
        /* Are there any restrictions in the CSI-2 case? */
        ret = sh_mobile_ceu_try_bus_param(icd, fmt->bits_per_sample);
        if (ret < 0)
            return 0;
    }

    if (!icd->host_priv) {
        struct v4l2_mbus_framefmt mf;
        struct v4l2_rect rect;
        int shift = 0;

        /* Add our control */
        v4l2_ctrl_new_std(&icd->ctrl_handler, &sh_mobile_ceu_ctrl_ops,
                  V4L2_CID_SHARPNESS, 0, 1, 1, 0);
        if (icd->ctrl_handler.error)
            return icd->ctrl_handler.error;

        /* FIXME: subwindow is lost between close / open */

        /* Cache current client geometry */
        ret = client_g_rect(sd, &rect);
        if (ret < 0)
            return ret;

        /* First time */
        ret = v4l2_subdev_call(sd, video, g_mbus_fmt, &mf);
        if (ret < 0)
            return ret;

        /*
         * All currently existing CEU implementations support 2560x1920
         * or larger frames. If the sensor is proposing too big a frame,
         * don't bother with possibly supportred by the CEU larger
         * sizes, just try VGA multiples. If needed, this can be
         * adjusted in the future.
         */
        while ((mf.width > pcdev->max_width ||
            mf.height > pcdev->max_height) && shift < 4) {
            /* Try 2560x1920, 1280x960, 640x480, 320x240 */
            mf.width    = 2560 >> shift;
            mf.height   = 1920 >> shift;
            ret = v4l2_device_call_until_err(sd->v4l2_dev,
                    soc_camera_grp_id(icd), video,
                    s_mbus_fmt, &mf);
            if (ret < 0)
                return ret;
            shift++;
        }

        if (shift == 4) {
            dev_err(dev, "Failed to configure the client below %ux%x\n",
                mf.width, mf.height);
            return -EIO;
        }

        dev_geo(dev, "camera fmt %ux%u\n", mf.width, mf.height);

        cam = kzalloc(sizeof(*cam), GFP_KERNEL);
        if (!cam)
            return -ENOMEM;

        /* We are called with current camera crop, initialise subrect with it */
        cam->rect   = rect;
        cam->subrect    = rect;

        cam->width  = mf.width;
        cam->height = mf.height;

        icd->host_priv = cam;
    } else {
        cam = icd->host_priv;
    }

    /* Beginning of a pass */
    if (!idx)
        cam->extra_fmt = NULL;

    switch (code) {
    case V4L2_MBUS_FMT_UYVY8_2X8:
    case V4L2_MBUS_FMT_VYUY8_2X8:
    case V4L2_MBUS_FMT_YUYV8_2X8:
    case V4L2_MBUS_FMT_YVYU8_2X8:
        if (cam->extra_fmt)
            break;

        /*
         * Our case is simple so far: for any of the above four camera
         * formats we add all our four synthesized NV* formats, so,
         * just marking the device with a single flag suffices. If
         * the format generation rules are more complex, you would have
         * to actually hang your already added / counted formats onto
         * the host_priv pointer and check whether the format you're
         * going to add now is already there.
         */
        cam->extra_fmt = sh_mobile_ceu_formats;

        n = ARRAY_SIZE(sh_mobile_ceu_formats);
        formats += n;
        for (k = 0; xlate && k < n; k++) {
            xlate->host_fmt = &sh_mobile_ceu_formats[k];
            xlate->code = code;
            xlate++;
            dev_dbg(dev, "Providing format %s using code %d\n",
                sh_mobile_ceu_formats[k].name, code);
        }
        break;
    default:
        if (!sh_mobile_ceu_packing_supported(fmt))
            return 0;
    }

    /* Generic pass-through */
    formats++;
    if (xlate) {
        xlate->host_fmt = fmt;
        xlate->code = code;
        xlate++;
        dev_dbg(dev, "Providing format %s in pass-through mode\n",
            fmt->name);
    }

    return formats;
}

static void sh_mobile_ceu_put_formats(struct soc_camera_device *icd)
{
    kfree(icd->host_priv);
    icd->host_priv = NULL;
}

/* Check if any dimension of r1 is smaller than respective one of r2 */
static bool is_smaller(const struct v4l2_rect *r1, const struct v4l2_rect *r2)
{
    return r1->width < r2->width || r1->height < r2->height;
}

/* Check if r1 fails to cover r2 */
static bool is_inside(const struct v4l2_rect *r1, const struct v4l2_rect *r2)
{
    return r1->left > r2->left || r1->top > r2->top ||
        r1->left + r1->width < r2->left + r2->width ||
        r1->top + r1->height < r2->top + r2->height;
}

static unsigned int scale_down(unsigned int size, unsigned int scale)
{
    return (size * 4096 + scale / 2) / scale;
}

static unsigned int calc_generic_scale(unsigned int input, unsigned int output)
{
    return (input * 4096 + output / 2) / output;
}

/* Get and store current client crop */
static int client_g_rect(struct v4l2_subdev *sd, struct v4l2_rect *rect)
{
    struct v4l2_crop crop;
    struct v4l2_cropcap cap;
    int ret;

    crop.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

    ret = v4l2_subdev_call(sd, video, g_crop, &crop);
    if (!ret) {
        *rect = crop.c;
        return ret;
    }

    /* Camera driver doesn't support .g_crop(), assume default rectangle */
    cap.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

    ret = v4l2_subdev_call(sd, video, cropcap, &cap);
    if (!ret)
        *rect = cap.defrect;

    return ret;
}

/* Client crop has changed, update our sub-rectangle to remain within the area */
static void update_subrect(struct sh_mobile_ceu_cam *cam)
{
    struct v4l2_rect *rect = &cam->rect, *subrect = &cam->subrect;

    if (rect->width < subrect->width)
        subrect->width = rect->width;

    if (rect->height < subrect->height)
        subrect->height = rect->height;

    if (rect->left > subrect->left)
        subrect->left = rect->left;
    else if (rect->left + rect->width >
         subrect->left + subrect->width)
        subrect->left = rect->left + rect->width -
            subrect->width;

    if (rect->top > subrect->top)
        subrect->top = rect->top;
    else if (rect->top + rect->height >
         subrect->top + subrect->height)
        subrect->top = rect->top + rect->height -
            subrect->height;
}

/*
 * The common for both scaling and cropping iterative approach is:
 * 1. try if the client can produce exactly what requested by the user
 * 2. if (1) failed, try to double the client image until we get one big enough
 * 3. if (2) failed, try to request the maximum image
 */
static int client_s_crop(struct soc_camera_device *icd, struct v4l2_crop *crop,
             struct v4l2_crop *cam_crop)
{
    struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
    struct v4l2_rect *rect = &crop->c, *cam_rect = &cam_crop->c;
    struct device *dev = sd->v4l2_dev->dev;
    struct sh_mobile_ceu_cam *cam = icd->host_priv;
    struct v4l2_cropcap cap;
    int ret;
    unsigned int width, height;

    v4l2_subdev_call(sd, video, s_crop, crop);
    ret = client_g_rect(sd, cam_rect);
    if (ret < 0)
        return ret;

    /*
     * Now cam_crop contains the current camera input rectangle, and it must
     * be within camera cropcap bounds
     */
    if (!memcmp(rect, cam_rect, sizeof(*rect))) {
        /* Even if camera S_CROP failed, but camera rectangle matches */
        dev_dbg(dev, "Camera S_CROP successful for %dx%d@%d:%d\n",
            rect->width, rect->height, rect->left, rect->top);
        cam->rect = *cam_rect;
        return 0;
    }

    /* Try to fix cropping, that camera hasn't managed to set */
    dev_geo(dev, "Fix camera S_CROP for %dx%d@%d:%d to %dx%d@%d:%d\n",
        cam_rect->width, cam_rect->height,
        cam_rect->left, cam_rect->top,
        rect->width, rect->height, rect->left, rect->top);

    /* We need sensor maximum rectangle */
    ret = v4l2_subdev_call(sd, video, cropcap, &cap);
    if (ret < 0)
        return ret;

    /* Put user requested rectangle within sensor bounds */
    soc_camera_limit_side(&rect->left, &rect->width, cap.bounds.left, 2,
                  cap.bounds.width);
    soc_camera_limit_side(&rect->top, &rect->height, cap.bounds.top, 4,
                  cap.bounds.height);

    /*
     * Popular special case - some cameras can only handle fixed sizes like
     * QVGA, VGA,... Take care to avoid infinite loop.
     */
    width = max(cam_rect->width, 2);
    height = max(cam_rect->height, 2);

    /*
     * Loop as long as sensor is not covering the requested rectangle and
     * is still within its bounds
     */
    while (!ret && (is_smaller(cam_rect, rect) ||
            is_inside(cam_rect, rect)) &&
           (cap.bounds.width > width || cap.bounds.height > height)) {

        width *= 2;
        height *= 2;

        cam_rect->width = width;
        cam_rect->height = height;

        /*
         * We do not know what capabilities the camera has to set up
         * left and top borders. We could try to be smarter in iterating
         * them, e.g., if camera current left is to the right of the
         * target left, set it to the middle point between the current
         * left and minimum left. But that would add too much
         * complexity: we would have to iterate each border separately.
         * Instead we just drop to the left and top bounds.
         */
        if (cam_rect->left > rect->left)
            cam_rect->left = cap.bounds.left;

        if (cam_rect->left + cam_rect->width < rect->left + rect->width)
            cam_rect->width = rect->left + rect->width -
                cam_rect->left;

        if (cam_rect->top > rect->top)
            cam_rect->top = cap.bounds.top;

        if (cam_rect->top + cam_rect->height < rect->top + rect->height)
            cam_rect->height = rect->top + rect->height -
                cam_rect->top;

        v4l2_subdev_call(sd, video, s_crop, cam_crop);
        ret = client_g_rect(sd, cam_rect);
        dev_geo(dev, "Camera S_CROP %d for %dx%d@%d:%d\n", ret,
            cam_rect->width, cam_rect->height,
            cam_rect->left, cam_rect->top);
    }

    /* S_CROP must not modify the rectangle */
    if (is_smaller(cam_rect, rect) || is_inside(cam_rect, rect)) {
        /*
         * The camera failed to configure a suitable cropping,
         * we cannot use the current rectangle, set to max
         */
        *cam_rect = cap.bounds;
        v4l2_subdev_call(sd, video, s_crop, cam_crop);
        ret = client_g_rect(sd, cam_rect);
        dev_geo(dev, "Camera S_CROP %d for max %dx%d@%d:%d\n", ret,
            cam_rect->width, cam_rect->height,
            cam_rect->left, cam_rect->top);
    }

    if (!ret) {
        cam->rect = *cam_rect;
        update_subrect(cam);
    }

    return ret;
}

/* Iterative s_mbus_fmt, also updates cached client crop on success */
static int client_s_fmt(struct soc_camera_device *icd,
            struct v4l2_mbus_framefmt *mf, bool ceu_can_scale)
{
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    struct sh_mobile_ceu_cam *cam = icd->host_priv;
    struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
    struct device *dev = icd->parent;
    unsigned int width = mf->width, height = mf->height, tmp_w, tmp_h;
    unsigned int max_width, max_height;
    struct v4l2_cropcap cap;
    bool ceu_1to1;
    int ret;

    ret = v4l2_device_call_until_err(sd->v4l2_dev,
                     soc_camera_grp_id(icd), video,
                     s_mbus_fmt, mf);
    if (ret < 0)
        return ret;

    dev_geo(dev, "camera scaled to %ux%u\n", mf->width, mf->height);

    if (width == mf->width && height == mf->height) {
        /* Perfect! The client has done it all. */
        ceu_1to1 = true;
        goto update_cache;
    }

    ceu_1to1 = false;
    if (!ceu_can_scale)
        goto update_cache;

    cap.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

    ret = v4l2_subdev_call(sd, video, cropcap, &cap);
    if (ret < 0)
        return ret;

    max_width = min(cap.bounds.width, pcdev->max_width);
    max_height = min(cap.bounds.height, pcdev->max_height);

    /* Camera set a format, but geometry is not precise, try to improve */
    tmp_w = mf->width;
    tmp_h = mf->height;

    /* width <= max_width && height <= max_height - guaranteed by try_fmt */
    while ((width > tmp_w || height > tmp_h) &&
           tmp_w < max_width && tmp_h < max_height) {
        tmp_w = min(2 * tmp_w, max_width);
        tmp_h = min(2 * tmp_h, max_height);
        mf->width = tmp_w;
        mf->height = tmp_h;
        ret = v4l2_device_call_until_err(sd->v4l2_dev,
                    soc_camera_grp_id(icd), video,
                    s_mbus_fmt, mf);
        dev_geo(dev, "Camera scaled to %ux%u\n",
            mf->width, mf->height);
        if (ret < 0) {
            /* This shouldn't happen */
            dev_err(dev, "Client failed to set format: %d\n", ret);
            return ret;
        }
    }

update_cache:
    /* Update cache */
    ret = client_g_rect(sd, &cam->rect);
    if (ret < 0)
        return ret;

    if (ceu_1to1)
        cam->subrect = cam->rect;
    else
        update_subrect(cam);

    return 0;
}

static int client_scale(struct soc_camera_device *icd,
            struct v4l2_mbus_framefmt *mf,
            unsigned int *width, unsigned int *height,
            bool ceu_can_scale)
{
    struct sh_mobile_ceu_cam *cam = icd->host_priv;
    struct device *dev = icd->parent;
    struct v4l2_mbus_framefmt mf_tmp = *mf;
    unsigned int scale_h, scale_v;
    int ret;

    /*
     * 5. Apply iterative camera S_FMT for camera user window (also updates
     *    client crop cache and the imaginary sub-rectangle).
     */
    ret = client_s_fmt(icd, &mf_tmp, ceu_can_scale);
    if (ret < 0)
        return ret;

    dev_geo(dev, "5: camera scaled to %ux%u\n",
        mf_tmp.width, mf_tmp.height);

    /* 6. Retrieve camera output window (g_fmt) */

    /* unneeded - it is already in "mf_tmp" */

    /* 7. Calculate new client scales. */
    scale_h = calc_generic_scale(cam->rect.width, mf_tmp.width);
    scale_v = calc_generic_scale(cam->rect.height, mf_tmp.height);

    mf->width   = mf_tmp.width;
    mf->height  = mf_tmp.height;
    mf->colorspace  = mf_tmp.colorspace;

    /*
     * 8. Calculate new CEU crop - apply camera scales to previously
     *    updated "effective" crop.
     */
    *width = scale_down(cam->subrect.width, scale_h);
    *height = scale_down(cam->subrect.height, scale_v);

    dev_geo(dev, "8: new client sub-window %ux%u\n", *width, *height);

    return 0;
}

/*
 * CEU can scale and crop, but we don't want to waste bandwidth and kill the
 * framerate by always requesting the maximum image from the client. See
 * Documentation/video4linux/sh_mobile_ceu_camera.txt for a description of
 * scaling and cropping algorithms and for the meaning of referenced here steps.
 */
static int sh_mobile_ceu_set_crop(struct soc_camera_device *icd,
                  const struct v4l2_crop *a)
{
    struct v4l2_crop a_writable = *a;
    const struct v4l2_rect *rect = &a_writable.c;
    struct device *dev = icd->parent;
    struct soc_camera_host *ici = to_soc_camera_host(dev);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    struct v4l2_crop cam_crop;
    struct sh_mobile_ceu_cam *cam = icd->host_priv;
    struct v4l2_rect *cam_rect = &cam_crop.c;
    struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
    struct v4l2_mbus_framefmt mf;
    unsigned int scale_cam_h, scale_cam_v, scale_ceu_h, scale_ceu_v,
        out_width, out_height;
    int interm_width, interm_height;
    u32 capsr, cflcr;
    int ret;

    dev_geo(dev, "S_CROP(%ux%u@%u:%u)\n", rect->width, rect->height,
        rect->left, rect->top);

    /* During camera cropping its output window can change too, stop CEU */
    capsr = capture_save_reset(pcdev);
    dev_dbg(dev, "CAPSR 0x%x, CFLCR 0x%x\n", capsr, pcdev->cflcr);

    /*
     * 1. - 2. Apply iterative camera S_CROP for new input window, read back
     * actual camera rectangle.
     */
    ret = client_s_crop(icd, &a_writable, &cam_crop);
    if (ret < 0)
        return ret;

    dev_geo(dev, "1-2: camera cropped to %ux%u@%u:%u\n",
        cam_rect->width, cam_rect->height,
        cam_rect->left, cam_rect->top);

    /* On success cam_crop contains current camera crop */

    /* 3. Retrieve camera output window */
    ret = v4l2_subdev_call(sd, video, g_mbus_fmt, &mf);
    if (ret < 0)
        return ret;

    if (mf.width > pcdev->max_width || mf.height > pcdev->max_height)
        return -EINVAL;

    /* 4. Calculate camera scales */
    scale_cam_h = calc_generic_scale(cam_rect->width, mf.width);
    scale_cam_v = calc_generic_scale(cam_rect->height, mf.height);

    /* Calculate intermediate window */
    interm_width    = scale_down(rect->width, scale_cam_h);
    interm_height   = scale_down(rect->height, scale_cam_v);

    if (interm_width < icd->user_width) {
        u32 new_scale_h;

        new_scale_h = calc_generic_scale(rect->width, icd->user_width);

        mf.width = scale_down(cam_rect->width, new_scale_h);
    }

    if (interm_height < icd->user_height) {
        u32 new_scale_v;

        new_scale_v = calc_generic_scale(rect->height, icd->user_height);

        mf.height = scale_down(cam_rect->height, new_scale_v);
    }

    if (interm_width < icd->user_width || interm_height < icd->user_height) {
        ret = v4l2_device_call_until_err(sd->v4l2_dev,
                    soc_camera_grp_id(icd), video,
                    s_mbus_fmt, &mf);
        if (ret < 0)
            return ret;

        dev_geo(dev, "New camera output %ux%u\n", mf.width, mf.height);
        scale_cam_h = calc_generic_scale(cam_rect->width, mf.width);
        scale_cam_v = calc_generic_scale(cam_rect->height, mf.height);
        interm_width    = scale_down(rect->width, scale_cam_h);
        interm_height   = scale_down(rect->height, scale_cam_v);
    }

    /* Cache camera output window */
    cam->width  = mf.width;
    cam->height = mf.height;

    if (pcdev->image_mode) {
        out_width   = min(interm_width, icd->user_width);
        out_height  = min(interm_height, icd->user_height);
    } else {
        out_width   = interm_width;
        out_height  = interm_height;
    }

    /*
     * 5. Calculate CEU scales from camera scales from results of (5) and
     *    the user window
     */
    scale_ceu_h = calc_scale(interm_width, &out_width);
    scale_ceu_v = calc_scale(interm_height, &out_height);

    dev_geo(dev, "5: CEU scales %u:%u\n", scale_ceu_h, scale_ceu_v);

    /* Apply CEU scales. */
    cflcr = scale_ceu_h | (scale_ceu_v << 16);
    if (cflcr != pcdev->cflcr) {
        pcdev->cflcr = cflcr;
        ceu_write(pcdev, CFLCR, cflcr);
    }

    icd->user_width  = out_width & ~3;
    icd->user_height = out_height & ~3;
    /* Offsets are applied at the CEU scaling filter input */
    cam->ceu_left    = scale_down(rect->left - cam_rect->left, scale_cam_h) & ~1;
    cam->ceu_top     = scale_down(rect->top - cam_rect->top, scale_cam_v) & ~1;

    /* 6. Use CEU cropping to crop to the new window. */
    sh_mobile_ceu_set_rect(icd);

    cam->subrect = *rect;

    dev_geo(dev, "6: CEU cropped to %ux%u@%u:%u\n",
        icd->user_width, icd->user_height,
        cam->ceu_left, cam->ceu_top);

    /* Restore capture. The CE bit can be cleared by the hardware */
    if (pcdev->active)
        capsr |= 1;
    capture_restore(pcdev, capsr);

    /* Even if only camera cropping succeeded */
    return ret;
}

static int sh_mobile_ceu_get_crop(struct soc_camera_device *icd,
                  struct v4l2_crop *a)
{
    struct sh_mobile_ceu_cam *cam = icd->host_priv;

    a->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
    a->c = cam->subrect;

    return 0;
}

/*
 * Calculate real client output window by applying new scales to the current
 * client crop. New scales are calculated from the requested output format and
 * CEU crop, mapped backed onto the client input (subrect).
 */
static void calculate_client_output(struct soc_camera_device *icd,
        const struct v4l2_pix_format *pix, struct v4l2_mbus_framefmt *mf)
{
    struct sh_mobile_ceu_cam *cam = icd->host_priv;
    struct device *dev = icd->parent;
    struct v4l2_rect *cam_subrect = &cam->subrect;
    unsigned int scale_v, scale_h;

    if (cam_subrect->width == cam->rect.width &&
        cam_subrect->height == cam->rect.height) {
        /* No sub-cropping */
        mf->width   = pix->width;
        mf->height  = pix->height;
        return;
    }

    /* 1.-2. Current camera scales and subwin - cached. */

    dev_geo(dev, "2: subwin %ux%u@%u:%u\n",
        cam_subrect->width, cam_subrect->height,
        cam_subrect->left, cam_subrect->top);

    /*
     * 3. Calculate new combined scales from input sub-window to requested
     *    user window.
     */

    /*
     * TODO: CEU cannot scale images larger than VGA to smaller than SubQCIF
     * (128x96) or larger than VGA
     */
    scale_h = calc_generic_scale(cam_subrect->width, pix->width);
    scale_v = calc_generic_scale(cam_subrect->height, pix->height);

    dev_geo(dev, "3: scales %u:%u\n", scale_h, scale_v);

    /*
     * 4. Calculate desired client output window by applying combined scales
     *    to client (real) input window.
     */
    mf->width   = scale_down(cam->rect.width, scale_h);
    mf->height  = scale_down(cam->rect.height, scale_v);
}

/* Similar to set_crop multistage iterative algorithm */
static int sh_mobile_ceu_set_fmt(struct soc_camera_device *icd,
                 struct v4l2_format *f)
{
    struct device *dev = icd->parent;
    struct soc_camera_host *ici = to_soc_camera_host(dev);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    struct sh_mobile_ceu_cam *cam = icd->host_priv;
    struct v4l2_pix_format *pix = &f->fmt.pix;
    struct v4l2_mbus_framefmt mf;
    __u32 pixfmt = pix->pixelformat;
    const struct soc_camera_format_xlate *xlate;
    /* Keep Compiler Happy */
    unsigned int ceu_sub_width = 0, ceu_sub_height = 0;
    u16 scale_v, scale_h;
    int ret;
    bool image_mode;
    enum v4l2_field field;

    switch (pix->field) {
    default:
        pix->field = V4L2_FIELD_NONE;
        /* fall-through */
    case V4L2_FIELD_INTERLACED_TB:
    case V4L2_FIELD_INTERLACED_BT:
    case V4L2_FIELD_NONE:
        field = pix->field;
        break;
    case V4L2_FIELD_INTERLACED:
        field = V4L2_FIELD_INTERLACED_TB;
        break;
    }

    xlate = soc_camera_xlate_by_fourcc(icd, pixfmt);
    if (!xlate) {
        dev_warn(dev, "Format %x not found\n", pixfmt);
        return -EINVAL;
    }

    /* 1.-4. Calculate desired client output geometry */
    calculate_client_output(icd, pix, &mf);
    mf.field    = pix->field;
    mf.colorspace   = pix->colorspace;
    mf.code     = xlate->code;

    switch (pixfmt) {
    case V4L2_PIX_FMT_NV12:
    case V4L2_PIX_FMT_NV21:
    case V4L2_PIX_FMT_NV16:
    case V4L2_PIX_FMT_NV61:
        image_mode = true;
        break;
    default:
        image_mode = false;
    }

    dev_geo(dev, "S_FMT(pix=0x%x, fld 0x%x, code 0x%x, %ux%u)\n", pixfmt, mf.field, mf.code,
        pix->width, pix->height);

    dev_geo(dev, "4: request camera output %ux%u\n", mf.width, mf.height);

    /* 5. - 9. */
    ret = client_scale(icd, &mf, &ceu_sub_width, &ceu_sub_height,
               image_mode && V4L2_FIELD_NONE == field);

    dev_geo(dev, "5-9: client scale return %d\n", ret);

    /* Done with the camera. Now see if we can improve the result */

    dev_geo(dev, "fmt %ux%u, requested %ux%u\n",
        mf.width, mf.height, pix->width, pix->height);
    if (ret < 0)
        return ret;

    if (mf.code != xlate->code)
        return -EINVAL;

    /* 9. Prepare CEU crop */
    cam->width = mf.width;
    cam->height = mf.height;

    /* 10. Use CEU scaling to scale to the requested user window. */

    /* We cannot scale up */
    if (pix->width > ceu_sub_width)
        ceu_sub_width = pix->width;

    if (pix->height > ceu_sub_height)
        ceu_sub_height = pix->height;

    pix->colorspace = mf.colorspace;

    if (image_mode) {
        /* Scale pix->{width x height} down to width x height */
        scale_h     = calc_scale(ceu_sub_width, &pix->width);
        scale_v     = calc_scale(ceu_sub_height, &pix->height);
    } else {
        pix->width  = ceu_sub_width;
        pix->height = ceu_sub_height;
        scale_h     = 0;
        scale_v     = 0;
    }

    pcdev->cflcr = scale_h | (scale_v << 16);

    /*
     * We have calculated CFLCR, the actual configuration will be performed
     * in sh_mobile_ceu_set_bus_param()
     */

    dev_geo(dev, "10: W: %u : 0x%x = %u, H: %u : 0x%x = %u\n",
        ceu_sub_width, scale_h, pix->width,
        ceu_sub_height, scale_v, pix->height);

    cam->code       = xlate->code;
    icd->current_fmt    = xlate;

    pcdev->field = field;
    pcdev->image_mode = image_mode;

    /* CFSZR requirement */
    pix->width  &= ~3;
    pix->height &= ~3;

    return 0;
}

#define CEU_CHDW_MAX    8188U   /* Maximum line stride */

static int sh_mobile_ceu_try_fmt(struct soc_camera_device *icd,
                 struct v4l2_format *f)
{
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    const struct soc_camera_format_xlate *xlate;
    struct v4l2_pix_format *pix = &f->fmt.pix;
    struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
    struct v4l2_mbus_framefmt mf;
    __u32 pixfmt = pix->pixelformat;
    int width, height;
    int ret;

    dev_geo(icd->parent, "TRY_FMT(pix=0x%x, %ux%u)\n",
         pixfmt, pix->width, pix->height);

    xlate = soc_camera_xlate_by_fourcc(icd, pixfmt);
    if (!xlate) {
        xlate = icd->current_fmt;
        dev_dbg(icd->parent, "Format %x not found, keeping %x\n",
            pixfmt, xlate->host_fmt->fourcc);
        pixfmt = xlate->host_fmt->fourcc;
        pix->pixelformat = pixfmt;
        pix->colorspace = icd->colorspace;
    }

    /* FIXME: calculate using depth and bus width */

    /* CFSZR requires height and width to be 4-pixel aligned */
    v4l_bound_align_image(&pix->width, 2, pcdev->max_width, 2,
                  &pix->height, 4, pcdev->max_height, 2, 0);

    width = pix->width;
    height = pix->height;

    /* limit to sensor capabilities */
    mf.width    = pix->width;
    mf.height   = pix->height;
    mf.field    = pix->field;
    mf.code     = xlate->code;
    mf.colorspace   = pix->colorspace;

    ret = v4l2_device_call_until_err(sd->v4l2_dev, soc_camera_grp_id(icd),
                     video, try_mbus_fmt, &mf);
    if (ret < 0)
        return ret;

    pix->width  = mf.width;
    pix->height = mf.height;
    pix->field  = mf.field;
    pix->colorspace = mf.colorspace;

    switch (pixfmt) {
    case V4L2_PIX_FMT_NV12:
    case V4L2_PIX_FMT_NV21:
    case V4L2_PIX_FMT_NV16:
    case V4L2_PIX_FMT_NV61:
        /* FIXME: check against rect_max after converting soc-camera */
        /* We can scale precisely, need a bigger image from camera */
        if (pix->width < width || pix->height < height) {
            /*
             * We presume, the sensor behaves sanely, i.e., if
             * requested a bigger rectangle, it will not return a
             * smaller one.
             */
            mf.width = pcdev->max_width;
            mf.height = pcdev->max_height;
            ret = v4l2_device_call_until_err(sd->v4l2_dev,
                    soc_camera_grp_id(icd), video,
                    try_mbus_fmt, &mf);
            if (ret < 0) {
                /* Shouldn't actually happen... */
                dev_err(icd->parent,
                    "FIXME: client try_fmt() = %d\n", ret);
                return ret;
            }
        }
        /* We will scale exactly */
        if (mf.width > width)
            pix->width = width;
        if (mf.height > height)
            pix->height = height;

        pix->bytesperline = max(pix->bytesperline, pix->width);
        pix->bytesperline = min(pix->bytesperline, CEU_CHDW_MAX);
        pix->bytesperline &= ~3;
        break;

    default:
        /* Configurable stride isn't supported in pass-through mode. */
        pix->bytesperline  = 0;
    }

    pix->width  &= ~3;
    pix->height &= ~3;
    pix->sizeimage  = 0;

    dev_geo(icd->parent, "%s(): return %d, fmt 0x%x, %ux%u\n",
        __func__, ret, pix->pixelformat, pix->width, pix->height);

    return ret;
}

static int sh_mobile_ceu_set_livecrop(struct soc_camera_device *icd,
                      const struct v4l2_crop *a)
{
    struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
    struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
    struct sh_mobile_ceu_dev *pcdev = ici->priv;
    u32 out_width = icd->user_width, out_height = icd->user_height;
    int ret;

    /* Freeze queue */
    pcdev->frozen = 1;
    /* Wait for frame */
    ret = wait_for_completion_interruptible(&pcdev->complete);
    /* Stop the client */
    ret = v4l2_subdev_call(sd, video, s_stream, 0);
    if (ret < 0)
        dev_warn(icd->parent,
             "Client failed to stop the stream: %d\n", ret);
    else
        /* Do the crop, if it fails, there's nothing more we can do */
        sh_mobile_ceu_set_crop(icd, a);

    dev_geo(icd->parent, "Output after crop: %ux%u\n", icd->user_width, icd->user_height);

    if (icd->user_width != out_width || icd->user_height != out_height) {
        struct v4l2_format f = {
            .type   = V4L2_BUF_TYPE_VIDEO_CAPTURE,
            .fmt.pix    = {
                .width      = out_width,
                .height     = out_height,
                .pixelformat    = icd->current_fmt->host_fmt->fourcc,
                .field      = pcdev->field,
                .colorspace = icd->colorspace,
            },
        };
        ret = sh_mobile_ceu_set_fmt(icd, &f);
        if (!ret && (out_width != f.fmt.pix.width ||
                 out_height != f.fmt.pix.height))
            ret = -EINVAL;
        if (!ret) {
            icd->user_width     = out_width & ~3;
            icd->user_height    = out_height & ~3;
            ret = sh_mobile_ceu_set_bus_param(icd);
        }
    }

    /* Thaw the queue */
    pcdev->frozen = 0;
    spin_lock_irq(&pcdev->lock);
    sh_mobile_ceu_capture(pcdev);
    spin_unlock_irq(&pcdev->lock);
    /* Start the client */
    ret = v4l2_subdev_call(sd, video, s_stream, 1);
    return ret;
}

static unsigned int sh_mobile_ceu_poll(struct file *file, poll_table *pt)
{
    struct soc_camera_device *icd = file->private_data;

    return vb2_poll(&icd->vb2_vidq, file, pt);
}

static int sh_mobile_ceu_querycap(struct soc_camera_host *ici,
                  struct v4l2_capability *cap)
{
    strlcpy(cap->card, "SuperH_Mobile_CEU", sizeof(cap->card));
    cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
    return 0;
}

static int sh_mobile_ceu_init_videobuf(struct vb2_queue *q,
                       struct soc_camera_device *icd)
{
    q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
    q->io_modes = VB2_MMAP | VB2_USERPTR;
    q->drv_priv = icd;
    q->ops = &sh_mobile_ceu_videobuf_ops;
    q->mem_ops = &vb2_dma_contig_memops;
    q->buf_struct_size = sizeof(struct sh_mobile_ceu_buffer);

    return vb2_queue_init(q);
}

static struct soc_camera_host_ops sh_mobile_ceu_host_ops = {
    .owner      = THIS_MODULE,
    .add        = sh_mobile_ceu_add_device,
    .remove     = sh_mobile_ceu_remove_device,
    .get_formats    = sh_mobile_ceu_get_formats,
    .put_formats    = sh_mobile_ceu_put_formats,
    .get_crop   = sh_mobile_ceu_get_crop,
    .set_crop   = sh_mobile_ceu_set_crop,
    .set_livecrop   = sh_mobile_ceu_set_livecrop,
    .set_fmt    = sh_mobile_ceu_set_fmt,
    .try_fmt    = sh_mobile_ceu_try_fmt,
    .poll       = sh_mobile_ceu_poll,
    .querycap   = sh_mobile_ceu_querycap,
    .set_bus_param  = sh_mobile_ceu_set_bus_param,
    .init_videobuf2 = sh_mobile_ceu_init_videobuf,
};

struct bus_wait {
    struct notifier_block   notifier;
    struct completion   completion;
    struct device       *dev;
};

static int bus_notify(struct notifier_block *nb,
              unsigned long action, void *data)
{
    struct device *dev = data;
    struct bus_wait *wait = container_of(nb, struct bus_wait, notifier);

    if (wait->dev != dev)
        return NOTIFY_DONE;

    switch (action) {
    case BUS_NOTIFY_UNBOUND_DRIVER:
        /* Protect from module unloading */
        wait_for_completion(&wait->completion);
        return NOTIFY_OK;
    }
    return NOTIFY_DONE;
}

static int __devinit sh_mobile_ceu_probe(struct platform_device *pdev)
{
    struct sh_mobile_ceu_dev *pcdev;
    struct resource *res;
    void __iomem *base;
    unsigned int irq;
    int err = 0;
    struct bus_wait wait = {
        .completion = COMPLETION_INITIALIZER_ONSTACK(wait.completion),
        .notifier.notifier_call = bus_notify,
    };
    struct sh_mobile_ceu_companion *csi2;

    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    irq = platform_get_irq(pdev, 0);
    if (!res || (int)irq <= 0) {
        dev_err(&pdev->dev, "Not enough CEU platform resources.\n");
        err = -ENODEV;
        goto exit;
    }

    pcdev = kzalloc(sizeof(*pcdev), GFP_KERNEL);
    if (!pcdev) {
        dev_err(&pdev->dev, "Could not allocate pcdev\n");
        err = -ENOMEM;
        goto exit;
    }

    INIT_LIST_HEAD(&pcdev->capture);
    spin_lock_init(&pcdev->lock);
    init_completion(&pcdev->complete);

    pcdev->pdata = pdev->dev.platform_data;
    if (!pcdev->pdata) {
        err = -EINVAL;
        dev_err(&pdev->dev, "CEU platform data not set.\n");
        goto exit_kfree;
    }

    pcdev->max_width = pcdev->pdata->max_width ? : 2560;
    pcdev->max_height = pcdev->pdata->max_height ? : 1920;

    base = ioremap_nocache(res->start, resource_size(res));
    if (!base) {
        err = -ENXIO;
        dev_err(&pdev->dev, "Unable to ioremap CEU registers.\n");
        goto exit_kfree;
    }

    pcdev->irq = irq;
    pcdev->base = base;
    pcdev->video_limit = 0; /* only enabled if second resource exists */

    res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
    if (res) {
        err = dma_declare_coherent_memory(&pdev->dev, res->start,
                          res->start,
                          resource_size(res),
                          DMA_MEMORY_MAP |
                          DMA_MEMORY_EXCLUSIVE);
        if (!err) {
            dev_err(&pdev->dev, "Unable to declare CEU memory.\n");
            err = -ENXIO;
            goto exit_iounmap;
        }

        pcdev->video_limit = resource_size(res);
    }

    /* request irq */
    err = request_irq(pcdev->irq, sh_mobile_ceu_irq, IRQF_DISABLED,
              dev_name(&pdev->dev), pcdev);
    if (err) {
        dev_err(&pdev->dev, "Unable to register CEU interrupt.\n");
        goto exit_release_mem;
    }

    pm_suspend_ignore_children(&pdev->dev, true);
    pm_runtime_enable(&pdev->dev);
    pm_runtime_resume(&pdev->dev);

    pcdev->ici.priv = pcdev;
    pcdev->ici.v4l2_dev.dev = &pdev->dev;
    pcdev->ici.nr = pdev->id;
    pcdev->ici.drv_name = dev_name(&pdev->dev);
    pcdev->ici.ops = &sh_mobile_ceu_host_ops;
    pcdev->ici.capabilities = SOCAM_HOST_CAP_STRIDE;

    pcdev->alloc_ctx = vb2_dma_contig_init_ctx(&pdev->dev);
    if (IS_ERR(pcdev->alloc_ctx)) {
        err = PTR_ERR(pcdev->alloc_ctx);
        goto exit_free_clk;
    }

    err = soc_camera_host_register(&pcdev->ici);
    if (err)
        goto exit_free_ctx;

    /* CSI2 interfacing */
    csi2 = pcdev->pdata->csi2;
    if (csi2) {
        struct platform_device *csi2_pdev =
            platform_device_alloc("sh-mobile-csi2", csi2->id);
        struct sh_csi2_pdata *csi2_pdata = csi2->platform_data;

        if (!csi2_pdev) {
            err = -ENOMEM;
            goto exit_host_unregister;
        }

        pcdev->csi2_pdev        = csi2_pdev;

        err = platform_device_add_data(csi2_pdev, csi2_pdata, sizeof(*csi2_pdata));
        if (err < 0)
            goto exit_pdev_put;

        csi2_pdata          = csi2_pdev->dev.platform_data;
        csi2_pdata->v4l2_dev        = &pcdev->ici.v4l2_dev;

        csi2_pdev->resource     = csi2->resource;
        csi2_pdev->num_resources    = csi2->num_resources;

        err = platform_device_add(csi2_pdev);
        if (err < 0)
            goto exit_pdev_put;

        wait.dev = &csi2_pdev->dev;

        err = bus_register_notifier(&platform_bus_type, &wait.notifier);
        if (err < 0)
            goto exit_pdev_unregister;

        /*
         * From this point the driver module will not unload, until
         * we complete the completion.
         */

        if (!csi2_pdev->dev.driver) {
            complete(&wait.completion);
            /* Either too late, or probing failed */
            bus_unregister_notifier(&platform_bus_type, &wait.notifier);
            err = -ENXIO;
            goto exit_pdev_unregister;
        }

        /*
         * The module is still loaded, in the worst case it is hanging
         * in device release on our completion. So, _now_ dereferencing
         * the "owner" is safe!
         */

        err = try_module_get(csi2_pdev->dev.driver->owner);

        /* Let notifier complete, if it has been locked */
        complete(&wait.completion);
        bus_unregister_notifier(&platform_bus_type, &wait.notifier);
        if (!err) {
            err = -ENODEV;
            goto exit_pdev_unregister;
        }
    }

    return 0;

exit_pdev_unregister:
    platform_device_del(pcdev->csi2_pdev);
exit_pdev_put:
    pcdev->csi2_pdev->resource = NULL;
    platform_device_put(pcdev->csi2_pdev);
exit_host_unregister:
    soc_camera_host_unregister(&pcdev->ici);
exit_free_ctx:
    vb2_dma_contig_cleanup_ctx(pcdev->alloc_ctx);
exit_free_clk:
    pm_runtime_disable(&pdev->dev);
    free_irq(pcdev->irq, pcdev);
exit_release_mem:
    if (platform_get_resource(pdev, IORESOURCE_MEM, 1))
        dma_release_declared_memory(&pdev->dev);
exit_iounmap:
    iounmap(base);
exit_kfree:
    kfree(pcdev);
exit:
    return err;
}

static int __devexit sh_mobile_ceu_remove(struct platform_device *pdev)
{
    struct soc_camera_host *soc_host = to_soc_camera_host(&pdev->dev);
    struct sh_mobile_ceu_dev *pcdev = container_of(soc_host,
                    struct sh_mobile_ceu_dev, ici);
    struct platform_device *csi2_pdev = pcdev->csi2_pdev;

    soc_camera_host_unregister(soc_host);
    pm_runtime_disable(&pdev->dev);
    free_irq(pcdev->irq, pcdev);
    if (platform_get_resource(pdev, IORESOURCE_MEM, 1))
        dma_release_declared_memory(&pdev->dev);
    iounmap(pcdev->base);
    vb2_dma_contig_cleanup_ctx(pcdev->alloc_ctx);
    if (csi2_pdev && csi2_pdev->dev.driver) {
        struct module *csi2_drv = csi2_pdev->dev.driver->owner;
        platform_device_del(csi2_pdev);
        csi2_pdev->resource = NULL;
        platform_device_put(csi2_pdev);
        module_put(csi2_drv);
    }
    kfree(pcdev);

    return 0;
}

static int sh_mobile_ceu_runtime_nop(struct device *dev)
{
    /* Runtime PM callback shared between ->runtime_suspend()
     * and ->runtime_resume(). Simply returns success.
     *
     * This driver re-initializes all registers after
     * pm_runtime_get_sync() anyway so there is no need
     * to save and restore registers here.
     */
    return 0;
}

static const struct dev_pm_ops sh_mobile_ceu_dev_pm_ops = {
    .runtime_suspend = sh_mobile_ceu_runtime_nop,
    .runtime_resume = sh_mobile_ceu_runtime_nop,
};

static struct platform_driver sh_mobile_ceu_driver = {
    .driver     = {
        .name   = "sh_mobile_ceu",
        .pm = &sh_mobile_ceu_dev_pm_ops,
    },
    .probe      = sh_mobile_ceu_probe,
    .remove     = __devexit_p(sh_mobile_ceu_remove),
};

static int __init sh_mobile_ceu_init(void)
{
    /* Whatever return code */
    request_module("sh_mobile_csi2");
    return platform_driver_register(&sh_mobile_ceu_driver);
}

static void __exit sh_mobile_ceu_exit(void)
{
    platform_driver_unregister(&sh_mobile_ceu_driver);
}

module_init(sh_mobile_ceu_init);
module_exit(sh_mobile_ceu_exit);

MODULE_DESCRIPTION("SuperH Mobile CEU driver");
MODULE_AUTHOR("Magnus Damm");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.0.6");
MODULE_ALIAS("platform:sh_mobile_ceu");