OMAP3: PM: decouple PER and CORE context save and restore

[linux-ginger.git] / drivers / media / video / sh_mobile_ceu_camera.c

/*
 * 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 <kernel@pengutronix.de>
 *
 * 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/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/version.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/videodev2.h>
#include <linux/pm_runtime.h>

#include <media/v4l2-common.h>
#include <media/v4l2-dev.h>
#include <media/soc_camera.h>
#include <media/sh_mobile_ceu.h>
#include <media/videobuf-dma-contig.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 videobuf_buffer vb; /* v4l buffer must be first */
        const struct soc_camera_data_format *fmt;
};

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

        unsigned int irq;
        void __iomem *base;
        unsigned long video_limit;

        /* lock used to protect videobuf */
        spinlock_t lock;
        struct list_head capture;
        struct videobuf_buffer *active;

        struct sh_mobile_ceu_info *pdata;

        u32 cflcr;

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

struct sh_mobile_ceu_cam {
        struct v4l2_rect ceu_rect;
        unsigned int cam_width;
        unsigned int cam_height;
        const struct soc_camera_data_format *extra_fmt;
        const struct soc_camera_data_format *camera_fmt;
};

static unsigned long make_bus_param(struct sh_mobile_ceu_dev *pcdev)
{
        unsigned long flags;

        flags = SOCAM_MASTER |
                SOCAM_PCLK_SAMPLE_RISING |
                SOCAM_HSYNC_ACTIVE_HIGH |
                SOCAM_HSYNC_ACTIVE_LOW |
                SOCAM_VSYNC_ACTIVE_HIGH |
                SOCAM_VSYNC_ACTIVE_LOW |
                SOCAM_DATA_ACTIVE_HIGH;

        if (pcdev->pdata->flags & SH_CEU_FLAG_USE_8BIT_BUS)
                flags |= SOCAM_DATAWIDTH_8;

        if (pcdev->pdata->flags & SH_CEU_FLAG_USE_16BIT_BUS)
                flags |= SOCAM_DATAWIDTH_16;

        if (flags & SOCAM_DATAWIDTH_MASK)
                return flags;

        return 0;
}

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);
}

/*
 *  Videobuf operations
 */
static int sh_mobile_ceu_videobuf_setup(struct videobuf_queue *vq,
                                        unsigned int *count,
                                        unsigned int *size)
{
        struct soc_camera_device *icd = vq->priv_data;
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;
        int bytes_per_pixel = (icd->current_fmt->depth + 7) >> 3;

        *size = PAGE_ALIGN(icd->user_width * icd->user_height *
                           bytes_per_pixel);

        if (0 == *count)
                *count = 2;

        if (pcdev->video_limit) {
                while (*size * *count > pcdev->video_limit)
                        (*count)--;
        }

        dev_dbg(icd->dev.parent, "count=%d, size=%d\n", *count, *size);

        return 0;
}

static void free_buffer(struct videobuf_queue *vq,
                        struct sh_mobile_ceu_buffer *buf)
{
        struct soc_camera_device *icd = vq->priv_data;
        struct device *dev = icd->dev.parent;

        dev_dbg(dev, "%s (vb=0x%p) 0x%08lx %zd\n", __func__,
                &buf->vb, buf->vb.baddr, buf->vb.bsize);

        if (in_interrupt())
                BUG();

        videobuf_waiton(&buf->vb, 0, 0);
        videobuf_dma_contig_free(vq, &buf->vb);
        dev_dbg(dev, "%s freed\n", __func__);
        buf->vb.state = VIDEOBUF_NEEDS_INIT;
}

#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_CAPCR_CTNCP (1 << 16) /* continuous capture mode (if set) */


static void 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;

        /* 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_CPEIE);
        ceu_write(pcdev, CETCR, ~ceu_read(pcdev, CETCR) & CEU_CETCR_MAGIC);
        ceu_write(pcdev, CEIER, ceu_read(pcdev, CEIER) | CEU_CEIER_CPEIE);
        ceu_write(pcdev, CAPCR, ceu_read(pcdev, CAPCR) & ~CEU_CAPCR_CTNCP);
        ceu_write(pcdev, CETCR, CEU_CETCR_MAGIC ^ CEU_CETCR_IGRW);

        if (!pcdev->active)
                return;

        phys_addr_top = videobuf_to_dma_contig(pcdev->active);
        ceu_write(pcdev, CDAYR, phys_addr_top);
        if (pcdev->is_interlaced) {
                phys_addr_bottom = phys_addr_top + icd->user_width;
                ceu_write(pcdev, CDBYR, phys_addr_bottom);
        }

        switch (icd->current_fmt->fourcc) {
        case V4L2_PIX_FMT_NV12:
        case V4L2_PIX_FMT_NV21:
        case V4L2_PIX_FMT_NV16:
        case V4L2_PIX_FMT_NV61:
                phys_addr_top += icd->user_width *
                        icd->user_height;
                ceu_write(pcdev, CDACR, phys_addr_top);
                if (pcdev->is_interlaced) {
                        phys_addr_bottom = phys_addr_top +
                                icd->user_width;
                        ceu_write(pcdev, CDBCR, phys_addr_bottom);
                }
        }

        pcdev->active->state = VIDEOBUF_ACTIVE;
        ceu_write(pcdev, CAPSR, 0x1); /* start capture */
}

static int sh_mobile_ceu_videobuf_prepare(struct videobuf_queue *vq,
                                          struct videobuf_buffer *vb,
                                          enum v4l2_field field)
{
        struct soc_camera_device *icd = vq->priv_data;
        struct sh_mobile_ceu_buffer *buf;
        int ret;

        buf = container_of(vb, struct sh_mobile_ceu_buffer, vb);

        dev_dbg(icd->dev.parent, "%s (vb=0x%p) 0x%08lx %zd\n", __func__,
                vb, vb->baddr, vb->bsize);

        /* Added list head initialization on alloc */
        WARN_ON(!list_empty(&vb->queue));

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

        BUG_ON(NULL == icd->current_fmt);

        if (buf->fmt    != icd->current_fmt ||
            vb->width   != icd->user_width ||
            vb->height  != icd->user_height ||
            vb->field   != field) {
                buf->fmt        = icd->current_fmt;
                vb->width       = icd->user_width;
                vb->height      = icd->user_height;
                vb->field       = field;
                vb->state       = VIDEOBUF_NEEDS_INIT;
        }

        vb->size = vb->width * vb->height * ((buf->fmt->depth + 7) >> 3);
        if (0 != vb->baddr && vb->bsize < vb->size) {
                ret = -EINVAL;
                goto out;
        }

        if (vb->state == VIDEOBUF_NEEDS_INIT) {
                ret = videobuf_iolock(vq, vb, NULL);
                if (ret)
                        goto fail;
                vb->state = VIDEOBUF_PREPARED;
        }

        return 0;
fail:
        free_buffer(vq, buf);
out:
        return ret;
}

/* Called under spinlock_irqsave(&pcdev->lock, ...) */
static void sh_mobile_ceu_videobuf_queue(struct videobuf_queue *vq,
                                         struct videobuf_buffer *vb)
{
        struct soc_camera_device *icd = vq->priv_data;
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;

        dev_dbg(icd->dev.parent, "%s (vb=0x%p) 0x%08lx %zd\n", __func__,
                vb, vb->baddr, vb->bsize);

        vb->state = VIDEOBUF_QUEUED;
        list_add_tail(&vb->queue, &pcdev->capture);

        if (!pcdev->active) {
                pcdev->active = vb;
                sh_mobile_ceu_capture(pcdev);
        }
}

static void sh_mobile_ceu_videobuf_release(struct videobuf_queue *vq,
                                           struct videobuf_buffer *vb)
{
        struct soc_camera_device *icd = vq->priv_data;
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;
        unsigned long flags;

        spin_lock_irqsave(&pcdev->lock, flags);

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

        if ((vb->state == VIDEOBUF_ACTIVE || vb->state == VIDEOBUF_QUEUED) &&
            !list_empty(&vb->queue)) {
                vb->state = VIDEOBUF_ERROR;
                list_del_init(&vb->queue);
        }

        spin_unlock_irqrestore(&pcdev->lock, flags);

        free_buffer(vq, container_of(vb, struct sh_mobile_ceu_buffer, vb));
}

static struct videobuf_queue_ops sh_mobile_ceu_videobuf_ops = {
        .buf_setup      = sh_mobile_ceu_videobuf_setup,
        .buf_prepare    = sh_mobile_ceu_videobuf_prepare,
        .buf_queue      = sh_mobile_ceu_videobuf_queue,
        .buf_release    = sh_mobile_ceu_videobuf_release,
};

static irqreturn_t sh_mobile_ceu_irq(int irq, void *data)
{
        struct sh_mobile_ceu_dev *pcdev = data;
        struct videobuf_buffer *vb;
        unsigned long flags;

        spin_lock_irqsave(&pcdev->lock, flags);

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

        list_del_init(&vb->queue);

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

        sh_mobile_ceu_capture(pcdev);

        vb->state = VIDEOBUF_DONE;
        do_gettimeofday(&vb->ts);
        vb->field_count++;
        wake_up(&vb->done);

out:
        spin_unlock_irqrestore(&pcdev->lock, flags);

        return IRQ_HANDLED;
}

/* 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->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;

        if (pcdev->icd)
                return -EBUSY;

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

        pm_runtime_get_sync(ici->v4l2_dev.dev);

        ceu_write(pcdev, CAPSR, 1 << 16); /* reset */
        while (ceu_read(pcdev, CSTSR) & 1)
                msleep(1);

        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->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;
        unsigned long flags;

        BUG_ON(icd != pcdev->icd);

        /* disable capture, disable interrupts */
        ceu_write(pcdev, CEIER, 0);
        ceu_write(pcdev, CAPSR, 1 << 16); /* reset */

        /* make sure active buffer is canceled */
        spin_lock_irqsave(&pcdev->lock, flags);
        if (pcdev->active) {
                list_del(&pcdev->active->queue);
                pcdev->active->state = VIDEOBUF_ERROR;
                wake_up_all(&pcdev->active->done);
                pcdev->active = NULL;
        }
        spin_unlock_irqrestore(&pcdev->lock, flags);

        pm_runtime_put_sync(ici->v4l2_dev.dev);

        dev_info(icd->dev.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,
                                   unsigned int out_width,
                                   unsigned int out_height)
{
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        struct sh_mobile_ceu_cam *cam = icd->host_priv;
        struct v4l2_rect *rect = &cam->ceu_rect;
        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_dbg(icd->dev.parent, "Crop %ux%u@%u:%u\n",
                rect->width, rect->height, rect->left, rect->top);

        left_offset     = rect->left;
        top_offset      = rect->top;

        if (pcdev->image_mode) {
                in_width = rect->width;
                if (!pcdev->is_16bit) {
                        in_width *= 2;
                        left_offset *= 2;
                }
                width = cdwdr_width = out_width;
        } else {
                unsigned int w_factor = (icd->current_fmt->depth + 7) >> 3;

                width = out_width * w_factor / 2;

                if (!pcdev->is_16bit)
                        w_factor *= 2;

                in_width = rect->width * w_factor / 2;
                left_offset = left_offset * w_factor / 2;

                cdwdr_width = width * 2;
        }

        height = out_height;
        in_height = rect->height;
        if (pcdev->is_interlaced) {
                height /= 2;
                in_height /= 2;
                top_offset /= 2;
                cdwdr_width *= 2;
        }

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

        dev_geo(icd->dev.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);
        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);
}

static int sh_mobile_ceu_set_bus_param(struct soc_camera_device *icd,
                                       __u32 pixfmt)
{
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;
        int ret;
        unsigned long camera_flags, common_flags, value;
        int yuv_lineskip;
        struct sh_mobile_ceu_cam *cam = icd->host_priv;
        u32 capsr = capture_save_reset(pcdev);

        camera_flags = icd->ops->query_bus_param(icd);
        common_flags = soc_camera_bus_param_compatible(camera_flags,
                                                       make_bus_param(pcdev));
        if (!common_flags)
                return -EINVAL;

        ret = icd->ops->set_bus_param(icd, common_flags);
        if (ret < 0)
                return ret;

        switch (common_flags & SOCAM_DATAWIDTH_MASK) {
        case SOCAM_DATAWIDTH_8:
                pcdev->is_16bit = 0;
                break;
        case SOCAM_DATAWIDTH_16:
                pcdev->is_16bit = 1;
                break;
        default:
                return -EINVAL;
        }

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

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

        switch (icd->current_fmt->fourcc) {
        case V4L2_PIX_FMT_NV12:
        case V4L2_PIX_FMT_NV21:
                yuv_lineskip = 1; /* skip for NV12/21, no skip for NV16/61 */
                /* fall-through */
        case V4L2_PIX_FMT_NV16:
        case V4L2_PIX_FMT_NV61:
                switch (cam->camera_fmt->fourcc) {
                case V4L2_PIX_FMT_UYVY:
                        value = 0x00000000; /* Cb0, Y0, Cr0, Y1 */
                        break;
                case V4L2_PIX_FMT_VYUY:
                        value = 0x00000100; /* Cr0, Y0, Cb0, Y1 */
                        break;
                case V4L2_PIX_FMT_YUYV:
                        value = 0x00000200; /* Y0, Cb0, Y1, Cr0 */
                        break;
                case V4L2_PIX_FMT_YVYU:
                        value = 0x00000300; /* Y0, Cr0, Y1, Cb0 */
                        break;
                default:
                        BUG();
                }
        }

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

        value |= common_flags & SOCAM_VSYNC_ACTIVE_LOW ? 1 << 1 : 0;
        value |= common_flags & SOCAM_HSYNC_ACTIVE_LOW ? 1 << 0 : 0;
        value |= pcdev->is_16bit ? 1 << 12 : 0;
        ceu_write(pcdev, CAMCR, value);

        ceu_write(pcdev, CAPCR, 0x00300000);
        ceu_write(pcdev, CAIFR, pcdev->is_interlaced ? 0x101 : 0);

        sh_mobile_ceu_set_rect(icd, icd->user_width, icd->user_height);
        mdelay(1);

        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 = 0x00000017;
        if (yuv_lineskip)
                value &= ~0x00000010; /* convert 4:2:2 -> 4:2:0 */

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

        dev_dbg(icd->dev.parent, "S_FMT successful for %c%c%c%c %ux%u\n",
                pixfmt & 0xff, (pixfmt >> 8) & 0xff,
                (pixfmt >> 16) & 0xff, (pixfmt >> 24) & 0xff,
                icd->user_width, icd->user_height);

        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)
{
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;
        unsigned long camera_flags, common_flags;

        camera_flags = icd->ops->query_bus_param(icd);
        common_flags = soc_camera_bus_param_compatible(camera_flags,
                                                       make_bus_param(pcdev));
        if (!common_flags)
                return -EINVAL;

        return 0;
}

static const struct soc_camera_data_format sh_mobile_ceu_formats[] = {
        {
                .name           = "NV12",
                .depth          = 12,
                .fourcc         = V4L2_PIX_FMT_NV12,
                .colorspace     = V4L2_COLORSPACE_JPEG,
        },
        {
                .name           = "NV21",
                .depth          = 12,
                .fourcc         = V4L2_PIX_FMT_NV21,
                .colorspace     = V4L2_COLORSPACE_JPEG,
        },
        {
                .name           = "NV16",
                .depth          = 16,
                .fourcc         = V4L2_PIX_FMT_NV16,
                .colorspace     = V4L2_COLORSPACE_JPEG,
        },
        {
                .name           = "NV61",
                .depth          = 16,
                .fourcc         = V4L2_PIX_FMT_NV61,
                .colorspace     = V4L2_COLORSPACE_JPEG,
        },
};

static int sh_mobile_ceu_get_formats(struct soc_camera_device *icd, int idx,
                                     struct soc_camera_format_xlate *xlate)
{
        struct device *dev = icd->dev.parent;
        int ret, k, n;
        int formats = 0;
        struct sh_mobile_ceu_cam *cam;

        ret = sh_mobile_ceu_try_bus_param(icd);
        if (ret < 0)
                return 0;

        if (!icd->host_priv) {
                cam = kzalloc(sizeof(*cam), GFP_KERNEL);
                if (!cam)
                        return -ENOMEM;

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

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

        switch (icd->formats[idx].fourcc) {
        case V4L2_PIX_FMT_UYVY:
        case V4L2_PIX_FMT_VYUY:
        case V4L2_PIX_FMT_YUYV:
        case V4L2_PIX_FMT_YVYU:
                if (cam->extra_fmt)
                        goto add_single_format;

                /*
                 * 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 = (void *)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->cam_fmt = icd->formats + idx;
                        xlate->buswidth = icd->formats[idx].depth;
                        xlate++;
                        dev_dbg(dev, "Providing format %s using %s\n",
                                sh_mobile_ceu_formats[k].name,
                                icd->formats[idx].name);
                }
        default:
add_single_format:
                /* Generic pass-through */
                formats++;
                if (xlate) {
                        xlate->host_fmt = icd->formats + idx;
                        xlate->cam_fmt = icd->formats + idx;
                        xlate->buswidth = icd->formats[idx].depth;
                        xlate++;
                        dev_dbg(dev,
                                "Providing format %s in pass-through mode\n",
                                icd->formats[idx].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(struct v4l2_rect *r1, struct v4l2_rect *r2)
{
        return r1->width < r2->width || r1->height < r2->height;
}

/* Check if r1 fails to cover r2 */
static bool is_inside(struct v4l2_rect *r1, 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 scale_up(unsigned int size, unsigned int scale)
{
        return (size * scale + 2048) / 4096;
}

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

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 < 0)
                return ret;

        *rect = cap.defrect;

        return ret;
}

/*
 * 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 v4l2_subdev *sd, struct v4l2_crop *crop,
                         struct v4l2_crop *cam_crop)
{
        struct v4l2_rect *rect = &crop->c, *cam_rect = &cam_crop->c;
        struct device *dev = sd->v4l2_dev->dev;
        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 %ux%u@%u:%u\n",
                        rect->width, rect->height, rect->left, rect->top);
                return 0;
        }

        /* Try to fix cropping, that camera hasn't managed to set */
        dev_geo(dev, "Fix camera S_CROP for %ux%u@%u:%u to %ux%u@%u:%u\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;

        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);

        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.
                 */
                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 %ux%u@%u:%u\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 %ux%u@%u:%u\n", ret,
                        cam_rect->width, cam_rect->height,
                        cam_rect->left, cam_rect->top);
        }

        return ret;
}

static int get_camera_scales(struct v4l2_subdev *sd, struct v4l2_rect *rect,
                             unsigned int *scale_h, unsigned int *scale_v)
{
        struct v4l2_format f;
        int ret;

        f.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

        ret = v4l2_subdev_call(sd, video, g_fmt, &f);
        if (ret < 0)
                return ret;

        *scale_h = calc_generic_scale(rect->width, f.fmt.pix.width);
        *scale_v = calc_generic_scale(rect->height, f.fmt.pix.height);

        return 0;
}

static int get_camera_subwin(struct soc_camera_device *icd,
                             struct v4l2_rect *cam_subrect,
                             unsigned int cam_hscale, unsigned int cam_vscale)
{
        struct sh_mobile_ceu_cam *cam = icd->host_priv;
        struct v4l2_rect *ceu_rect = &cam->ceu_rect;

        if (!ceu_rect->width) {
                struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
                struct device *dev = icd->dev.parent;
                struct v4l2_format f;
                struct v4l2_pix_format *pix = &f.fmt.pix;
                int ret;
                /* First time */

                f.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

                ret = v4l2_subdev_call(sd, video, g_fmt, &f);
                if (ret < 0)
                        return ret;

                dev_geo(dev, "camera fmt %ux%u\n", pix->width, pix->height);

                if (pix->width > 2560) {
                        ceu_rect->width  = 2560;
                        ceu_rect->left   = (pix->width - 2560) / 2;
                } else {
                        ceu_rect->width  = pix->width;
                        ceu_rect->left   = 0;
                }

                if (pix->height > 1920) {
                        ceu_rect->height = 1920;
                        ceu_rect->top    = (pix->height - 1920) / 2;
                } else {
                        ceu_rect->height = pix->height;
                        ceu_rect->top    = 0;
                }

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

        cam_subrect->width      = scale_up(ceu_rect->width, cam_hscale);
        cam_subrect->left       = scale_up(ceu_rect->left, cam_hscale);
        cam_subrect->height     = scale_up(ceu_rect->height, cam_vscale);
        cam_subrect->top        = scale_up(ceu_rect->top, cam_vscale);

        return 0;
}

static int client_s_fmt(struct soc_camera_device *icd, struct v4l2_format *f,
                        bool ceu_can_scale)
{
        struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
        struct device *dev = icd->dev.parent;
        struct v4l2_pix_format *pix = &f->fmt.pix;
        unsigned int width = pix->width, height = pix->height, tmp_w, tmp_h;
        unsigned int max_width, max_height;
        struct v4l2_cropcap cap;
        int ret;

        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, 2560);
        max_height = min(cap.bounds.height, 1920);

        ret = v4l2_subdev_call(sd, video, s_fmt, f);
        if (ret < 0)
                return ret;

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

        if ((width == pix->width && height == pix->height) || !ceu_can_scale)
                return 0;

        /* Camera set a format, but geometry is not precise, try to improve */
        tmp_w = pix->width;
        tmp_h = pix->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);
                pix->width = tmp_w;
                pix->height = tmp_h;
                ret = v4l2_subdev_call(sd, video, s_fmt, f);
                dev_geo(dev, "Camera scaled to %ux%u\n",
                        pix->width, pix->height);
                if (ret < 0) {
                        /* This shouldn't happen */
                        dev_err(dev, "Client failed to set format: %d\n", ret);
                        return ret;
                }
        }

        return 0;
}

/**
 * @rect        - camera cropped rectangle
 * @sub_rect    - CEU cropped rectangle, mapped back to camera input area
 * @ceu_rect    - on output calculated CEU crop rectangle
 */
static int client_scale(struct soc_camera_device *icd, struct v4l2_rect *rect,
                        struct v4l2_rect *sub_rect, struct v4l2_rect *ceu_rect,
                        struct v4l2_format *f, bool ceu_can_scale)
{
        struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
        struct sh_mobile_ceu_cam *cam = icd->host_priv;
        struct device *dev = icd->dev.parent;
        struct v4l2_format f_tmp = *f;
        struct v4l2_pix_format *pix_tmp = &f_tmp.fmt.pix;
        unsigned int scale_h, scale_v;
        int ret;

        /* 5. Apply iterative camera S_FMT for camera user window. */
        ret = client_s_fmt(icd, &f_tmp, ceu_can_scale);
        if (ret < 0)
                return ret;

        dev_geo(dev, "5: camera scaled to %ux%u\n",
                pix_tmp->width, pix_tmp->height);

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

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

        /* 7. Calculate new camera scales. */
        ret = get_camera_scales(sd, rect, &scale_h, &scale_v);
        if (ret < 0)
                return ret;

        dev_geo(dev, "7: camera scales %u:%u\n", scale_h, scale_v);

        cam->cam_width          = pix_tmp->width;
        cam->cam_height         = pix_tmp->height;
        f->fmt.pix.width        = pix_tmp->width;
        f->fmt.pix.height       = pix_tmp->height;

        /*
         * 8. Calculate new CEU crop - apply camera scales to previously
         *    calculated "effective" crop.
         */
        ceu_rect->left = scale_down(sub_rect->left, scale_h);
        ceu_rect->width = scale_down(sub_rect->width, scale_h);
        ceu_rect->top = scale_down(sub_rect->top, scale_v);
        ceu_rect->height = scale_down(sub_rect->height, scale_v);

        dev_geo(dev, "8: new CEU rect %ux%u@%u:%u\n",
                ceu_rect->width, ceu_rect->height,
                ceu_rect->left, ceu_rect->top);

        return 0;
}

/* Get combined scales */
static int get_scales(struct soc_camera_device *icd,
                      unsigned int *scale_h, unsigned int *scale_v)
{
        struct sh_mobile_ceu_cam *cam = icd->host_priv;
        struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
        struct v4l2_crop cam_crop;
        unsigned int width_in, height_in;
        int ret;

        cam_crop.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

        ret = client_g_rect(sd, &cam_crop.c);
        if (ret < 0)
                return ret;

        ret = get_camera_scales(sd, &cam_crop.c, scale_h, scale_v);
        if (ret < 0)
                return ret;

        width_in = scale_up(cam->ceu_rect.width, *scale_h);
        height_in = scale_up(cam->ceu_rect.height, *scale_v);

        *scale_h = calc_generic_scale(cam->ceu_rect.width, icd->user_width);
        *scale_v = calc_generic_scale(cam->ceu_rect.height, icd->user_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_camera_ceu.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,
                                  struct v4l2_crop *a)
{
        struct v4l2_rect *rect = &a->c;
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        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, *ceu_rect = &cam->ceu_rect;
        struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
        struct device *dev = icd->dev.parent;
        struct v4l2_format f;
        struct v4l2_pix_format *pix = &f.fmt.pix;
        unsigned int scale_comb_h, scale_comb_v, scale_ceu_h, scale_ceu_v,
                out_width, out_height;
        u32 capsr, cflcr;
        int ret;

        /* 1. Calculate current combined scales. */
        ret = get_scales(icd, &scale_comb_h, &scale_comb_v);
        if (ret < 0)
                return ret;

        dev_geo(dev, "1: combined scales %u:%u\n", scale_comb_h, scale_comb_v);

        /* 2. Apply iterative camera S_CROP for new input window. */
        ret = client_s_crop(sd, a, &cam_crop);
        if (ret < 0)
                return ret;

        dev_geo(dev, "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. If old combined scales applied to new crop produce an impossible
         *    user window, adjust scales to produce nearest possible window.
         */
        out_width       = scale_down(rect->width, scale_comb_h);
        out_height      = scale_down(rect->height, scale_comb_v);

        if (out_width > 2560)
                out_width = 2560;
        else if (out_width < 2)
                out_width = 2;

        if (out_height > 1920)
                out_height = 1920;
        else if (out_height < 4)
                out_height = 4;

        dev_geo(dev, "3: Adjusted output %ux%u\n", out_width, out_height);

        /* 4. Use G_CROP to retrieve actual input window: already in cam_crop */

        /*
         * 5. Using actual input window and calculated combined scales calculate
         *    camera target output window.
         */
        pix->width              = scale_down(cam_rect->width, scale_comb_h);
        pix->height             = scale_down(cam_rect->height, scale_comb_v);

        dev_geo(dev, "5: camera target %ux%u\n", pix->width, pix->height);

        /* 6. - 9. */
        pix->pixelformat        = cam->camera_fmt->fourcc;
        pix->colorspace         = cam->camera_fmt->colorspace;

        capsr = capture_save_reset(pcdev);
        dev_dbg(dev, "CAPSR 0x%x, CFLCR 0x%x\n", capsr, pcdev->cflcr);

        /* Make relative to camera rectangle */
        rect->left              -= cam_rect->left;
        rect->top               -= cam_rect->top;

        f.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

        ret = client_scale(icd, cam_rect, rect, ceu_rect, &f,
                           pcdev->image_mode && !pcdev->is_interlaced);

        dev_geo(dev, "6-9: %d\n", ret);

        /* 10. Use CEU cropping to crop to the new window. */
        sh_mobile_ceu_set_rect(icd, out_width, out_height);

        dev_geo(dev, "10: CEU cropped to %ux%u@%u:%u\n",
                ceu_rect->width, ceu_rect->height,
                ceu_rect->left, ceu_rect->top);

        /*
         * 11. Calculate CEU scales from camera scales from results of (10) and
         *     user window from (3)
         */
        scale_ceu_h = calc_scale(ceu_rect->width, &out_width);
        scale_ceu_v = calc_scale(ceu_rect->height, &out_height);

        dev_geo(dev, "11: CEU scales %u:%u\n", scale_ceu_h, scale_ceu_v);

        /* 12. Apply CEU scales. */
        cflcr = scale_ceu_h | (scale_ceu_v << 16);
        if (cflcr != pcdev->cflcr) {
                pcdev->cflcr = cflcr;
                ceu_write(pcdev, CFLCR, cflcr);
        }

        /* Restore capture */
        if (pcdev->active)
                capsr |= 1;
        capture_restore(pcdev, capsr);

        icd->user_width = out_width;
        icd->user_height = out_height;

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

/* Similar to set_crop multistage iterative algorithm */
static int sh_mobile_ceu_set_fmt(struct soc_camera_device *icd,
                                 struct v4l2_format *f)
{
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        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_format cam_f = *f;
        struct v4l2_pix_format *cam_pix = &cam_f.fmt.pix;
        struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
        struct device *dev = icd->dev.parent;
        __u32 pixfmt = pix->pixelformat;
        const struct soc_camera_format_xlate *xlate;
        struct v4l2_crop cam_crop;
        struct v4l2_rect *cam_rect = &cam_crop.c, cam_subrect, ceu_rect;
        unsigned int scale_cam_h, scale_cam_v;
        u16 scale_v, scale_h;
        int ret;
        bool is_interlaced, image_mode;

        switch (pix->field) {
        case V4L2_FIELD_INTERLACED:
                is_interlaced = true;
                break;
        case V4L2_FIELD_ANY:
        default:
                pix->field = V4L2_FIELD_NONE;
                /* fall-through */
        case V4L2_FIELD_NONE:
                is_interlaced = false;
                break;
        }

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

        /* 1. Calculate current camera scales. */
        cam_crop.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

        ret = client_g_rect(sd, cam_rect);
        if (ret < 0)
                return ret;

        ret = get_camera_scales(sd, cam_rect, &scale_cam_h, &scale_cam_v);
        if (ret < 0)
                return ret;

        dev_geo(dev, "1: camera scales %u:%u\n", scale_cam_h, scale_cam_v);

        /*
         * 2. Calculate "effective" input crop (sensor subwindow) - CEU crop
         *    scaled back at current camera scales onto input window.
         */
        ret = get_camera_subwin(icd, &cam_subrect, scale_cam_h, scale_cam_v);
        if (ret < 0)
                return ret;

        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 "effective" input window to
         *    requested user window.
         */
        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 camera output window by applying combined scales to real
         *    input window.
         */
        cam_pix->width = scale_down(cam_rect->width, scale_h);
        cam_pix->height = scale_down(cam_rect->height, scale_v);
        cam_pix->pixelformat = xlate->cam_fmt->fourcc;

        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, "4: camera output %ux%u\n",
                cam_pix->width, cam_pix->height);

        /* 5. - 9. */
        ret = client_scale(icd, cam_rect, &cam_subrect, &ceu_rect, &cam_f,
                           image_mode && !is_interlaced);

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

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

        dev_dbg(dev, "Camera %d fmt %ux%u, requested %ux%u\n",
                ret, cam_pix->width, cam_pix->height, pix->width, pix->height);
        if (ret < 0)
                return ret;

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

        /* We cannot scale up */
        if (pix->width > cam_pix->width)
                pix->width = cam_pix->width;
        if (pix->width > ceu_rect.width)
                pix->width = ceu_rect.width;

        if (pix->height > cam_pix->height)
                pix->height = cam_pix->height;
        if (pix->height > ceu_rect.height)
                pix->height = ceu_rect.height;

        /* Let's rock: scale pix->{width x height} down to width x height */
        scale_h = calc_scale(ceu_rect.width, &pix->width);
        scale_v = calc_scale(ceu_rect.height, &pix->height);

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

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

        icd->buswidth = xlate->buswidth;
        icd->current_fmt = xlate->host_fmt;
        cam->camera_fmt = xlate->cam_fmt;
        cam->ceu_rect = ceu_rect;

        pcdev->is_interlaced = is_interlaced;
        pcdev->image_mode = image_mode;

        return 0;
}

static int sh_mobile_ceu_try_fmt(struct soc_camera_device *icd,
                                 struct v4l2_format *f)
{
        const struct soc_camera_format_xlate *xlate;
        struct v4l2_pix_format *pix = &f->fmt.pix;
        struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
        __u32 pixfmt = pix->pixelformat;
        int width, height;
        int ret;

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

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

        v4l_bound_align_image(&pix->width, 2, 2560, 1,
                              &pix->height, 4, 1920, 2, 0);

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

        pix->bytesperline = pix->width *
                DIV_ROUND_UP(xlate->host_fmt->depth, 8);
        pix->sizeimage = pix->height * pix->bytesperline;

        pix->pixelformat = xlate->cam_fmt->fourcc;

        /* limit to sensor capabilities */
        ret = v4l2_subdev_call(sd, video, try_fmt, f);
        pix->pixelformat = pixfmt;
        if (ret < 0)
                return ret;

        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) {
                        int tmp_w = pix->width, tmp_h = pix->height;
                        pix->width = 2560;
                        pix->height = 1920;
                        ret = v4l2_subdev_call(sd, video, try_fmt, f);
                        if (ret < 0) {
                                /* Shouldn't actually happen... */
                                dev_err(icd->dev.parent,
                                        "FIXME: try_fmt() returned %d\n", ret);
                                pix->width = tmp_w;
                                pix->height = tmp_h;
                        }
                }
                if (pix->width > width)
                        pix->width = width;
                if (pix->height > height)
                        pix->height = height;
        }

        return ret;
}

static int sh_mobile_ceu_reqbufs(struct soc_camera_file *icf,
                                 struct v4l2_requestbuffers *p)
{
        int i;

        /* This is for locking debugging only. I removed spinlocks and now I
         * check whether .prepare is ever called on a linked buffer, or whether
         * a dma IRQ can occur for an in-work or unlinked buffer. Until now
         * it hadn't triggered */
        for (i = 0; i < p->count; i++) {
                struct sh_mobile_ceu_buffer *buf;

                buf = container_of(icf->vb_vidq.bufs[i],
                                   struct sh_mobile_ceu_buffer, vb);
                INIT_LIST_HEAD(&buf->vb.queue);
        }

        return 0;
}

static unsigned int sh_mobile_ceu_poll(struct file *file, poll_table *pt)
{
        struct soc_camera_file *icf = file->private_data;
        struct sh_mobile_ceu_buffer *buf;

        buf = list_entry(icf->vb_vidq.stream.next,
                         struct sh_mobile_ceu_buffer, vb.stream);

        poll_wait(file, &buf->vb.done, pt);

        if (buf->vb.state == VIDEOBUF_DONE ||
            buf->vb.state == VIDEOBUF_ERROR)
                return POLLIN|POLLRDNORM;

        return 0;
}

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->version = KERNEL_VERSION(0, 0, 5);
        cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
        return 0;
}

static void sh_mobile_ceu_init_videobuf(struct videobuf_queue *q,
                                        struct soc_camera_device *icd)
{
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;

        videobuf_queue_dma_contig_init(q,
                                       &sh_mobile_ceu_videobuf_ops,
                                       icd->dev.parent, &pcdev->lock,
                                       V4L2_BUF_TYPE_VIDEO_CAPTURE,
                                       pcdev->is_interlaced ?
                                       V4L2_FIELD_INTERLACED : V4L2_FIELD_NONE,
                                       sizeof(struct sh_mobile_ceu_buffer),
                                       icd);
}

static int sh_mobile_ceu_get_ctrl(struct soc_camera_device *icd,
                                  struct v4l2_control *ctrl)
{
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;
        u32 val;

        switch (ctrl->id) {
        case V4L2_CID_SHARPNESS:
                val = ceu_read(pcdev, CLFCR);
                ctrl->value = val ^ 1;
                return 0;
        }
        return -ENOIOCTLCMD;
}

static int sh_mobile_ceu_set_ctrl(struct soc_camera_device *icd,
                                  struct v4l2_control *ctrl)
{
        struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
        struct sh_mobile_ceu_dev *pcdev = ici->priv;

        switch (ctrl->id) {
        case V4L2_CID_SHARPNESS:
                switch (icd->current_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->value);
                        return 0;
                }
                return -EINVAL;
        }
        return -ENOIOCTLCMD;
}

static const struct v4l2_queryctrl sh_mobile_ceu_controls[] = {
        {
                .id             = V4L2_CID_SHARPNESS,
                .type           = V4L2_CTRL_TYPE_BOOLEAN,
                .name           = "Low-pass filter",
                .minimum        = 0,
                .maximum        = 1,
                .step           = 1,
                .default_value  = 0,
        },
};

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,
        .set_crop       = sh_mobile_ceu_set_crop,
        .set_fmt        = sh_mobile_ceu_set_fmt,
        .try_fmt        = sh_mobile_ceu_try_fmt,
        .set_ctrl       = sh_mobile_ceu_set_ctrl,
        .get_ctrl       = sh_mobile_ceu_get_ctrl,
        .reqbufs        = sh_mobile_ceu_reqbufs,
        .poll           = sh_mobile_ceu_poll,
        .querycap       = sh_mobile_ceu_querycap,
        .set_bus_param  = sh_mobile_ceu_set_bus_param,
        .init_videobuf  = sh_mobile_ceu_init_videobuf,
        .controls       = sh_mobile_ceu_controls,
        .num_controls   = ARRAY_SIZE(sh_mobile_ceu_controls),
};

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;

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        irq = platform_get_irq(pdev, 0);
        if (!res || !irq) {
                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);

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

        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;

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

        return 0;

exit_free_irq:
        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);

        soc_camera_host_unregister(soc_host);
        free_irq(pcdev->irq, pcdev);
        if (platform_get_resource(pdev, IORESOURCE_MEM, 1))
                dma_release_declared_memory(&pdev->dev);
        iounmap(pcdev->base);
        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 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         = __exit_p(sh_mobile_ceu_remove),
};

static int __init sh_mobile_ceu_init(void)
{
        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_ALIAS("platform:sh_mobile_ceu");