/*
 * TI OMAP4 ISS V4L2 Driver - ISP IPIPEIF module
 *
 * Copyright (C) 2012 Texas Instruments, Inc.
 *
 * Author: Sergio Aguirre <sergio.a.aguirre@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/mm.h>
#include <linux/sched.h>

#include "iss.h"
#include "iss_regs.h"
#include "iss_ipipeif.h"

static const unsigned int ipipeif_fmts[] = {
        MEDIA_BUS_FMT_SGRBG10_1X10,
        MEDIA_BUS_FMT_SRGGB10_1X10,
        MEDIA_BUS_FMT_SBGGR10_1X10,
        MEDIA_BUS_FMT_SGBRG10_1X10,
        MEDIA_BUS_FMT_UYVY8_1X16,
        MEDIA_BUS_FMT_YUYV8_1X16,
};

/*
 * ipipeif_print_status - Print current IPIPEIF Module register values.
 * @ipipeif: Pointer to ISS ISP IPIPEIF device.
 *
 * Also prints other debug information stored in the IPIPEIF module.
 */
#define IPIPEIF_PRINT_REGISTER(iss, name)\
        dev_dbg(iss->dev, "###IPIPEIF " #name "=0x%08x\n", \
                iss_reg_read(iss, OMAP4_ISS_MEM_ISP_IPIPEIF, IPIPEIF_##name))

#define ISIF_PRINT_REGISTER(iss, name)\
        dev_dbg(iss->dev, "###ISIF " #name "=0x%08x\n", \
                iss_reg_read(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_##name))

#define ISP5_PRINT_REGISTER(iss, name)\
        dev_dbg(iss->dev, "###ISP5 " #name "=0x%08x\n", \
                iss_reg_read(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_##name))

static void ipipeif_print_status(struct iss_ipipeif_device *ipipeif)
{
        struct iss_device *iss = to_iss_device(ipipeif);

        dev_dbg(iss->dev, "-------------IPIPEIF Register dump-------------\n");

        IPIPEIF_PRINT_REGISTER(iss, CFG1);
        IPIPEIF_PRINT_REGISTER(iss, CFG2);

        ISIF_PRINT_REGISTER(iss, SYNCEN);
        ISIF_PRINT_REGISTER(iss, CADU);
        ISIF_PRINT_REGISTER(iss, CADL);
        ISIF_PRINT_REGISTER(iss, MODESET);
        ISIF_PRINT_REGISTER(iss, CCOLP);
        ISIF_PRINT_REGISTER(iss, SPH);
        ISIF_PRINT_REGISTER(iss, LNH);
        ISIF_PRINT_REGISTER(iss, LNV);
        ISIF_PRINT_REGISTER(iss, VDINT(0));
        ISIF_PRINT_REGISTER(iss, HSIZE);

        ISP5_PRINT_REGISTER(iss, SYSCONFIG);
        ISP5_PRINT_REGISTER(iss, CTRL);
        ISP5_PRINT_REGISTER(iss, IRQSTATUS(0));
        ISP5_PRINT_REGISTER(iss, IRQENABLE_SET(0));
        ISP5_PRINT_REGISTER(iss, IRQENABLE_CLR(0));

        dev_dbg(iss->dev, "-----------------------------------------------\n");
}

static void ipipeif_write_enable(struct iss_ipipeif_device *ipipeif, u8 enable)
{
        struct iss_device *iss = to_iss_device(ipipeif);

        iss_reg_update(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_SYNCEN,
                       ISIF_SYNCEN_DWEN, enable ? ISIF_SYNCEN_DWEN : 0);
}

/*
 * ipipeif_enable - Enable/Disable IPIPEIF.
 * @enable: enable flag
 *
 */
static void ipipeif_enable(struct iss_ipipeif_device *ipipeif, u8 enable)
{
        struct iss_device *iss = to_iss_device(ipipeif);

        iss_reg_update(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_SYNCEN,
                       ISIF_SYNCEN_SYEN, enable ? ISIF_SYNCEN_SYEN : 0);
}

/* -----------------------------------------------------------------------------
 * Format- and pipeline-related configuration helpers
 */

/*
 * ipipeif_set_outaddr - Set memory address to save output image
 * @ipipeif: Pointer to ISP IPIPEIF device.
 * @addr: 32-bit memory address aligned on 32 byte boundary.
 *
 * Sets the memory address where the output will be saved.
 */
static void ipipeif_set_outaddr(struct iss_ipipeif_device *ipipeif, u32 addr)
{
        struct iss_device *iss = to_iss_device(ipipeif);

        /* Save address split in Base Address H & L */
        iss_reg_write(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_CADU,
                      (addr >> (16 + 5)) & ISIF_CADU_MASK);
        iss_reg_write(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_CADL,
                      (addr >> 5) & ISIF_CADL_MASK);
}

static void ipipeif_configure(struct iss_ipipeif_device *ipipeif)
{
        struct iss_device *iss = to_iss_device(ipipeif);
        const struct iss_format_info *info;
        struct v4l2_mbus_framefmt *format;
        u32 isif_ccolp = 0;

        omap4iss_configure_bridge(iss, ipipeif->input);

        /* IPIPEIF_PAD_SINK */
        format = &ipipeif->formats[IPIPEIF_PAD_SINK];

        /* IPIPEIF with YUV422 input from ISIF */
        iss_reg_clr(iss, OMAP4_ISS_MEM_ISP_IPIPEIF, IPIPEIF_CFG1,
                    IPIPEIF_CFG1_INPSRC1_MASK | IPIPEIF_CFG1_INPSRC2_MASK);

        /* Select ISIF/IPIPEIF input format */
        switch (format->code) {
        case MEDIA_BUS_FMT_UYVY8_1X16:
        case MEDIA_BUS_FMT_YUYV8_1X16:
                iss_reg_update(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_MODESET,
                               ISIF_MODESET_CCDMD | ISIF_MODESET_INPMOD_MASK |
                               ISIF_MODESET_CCDW_MASK,
                               ISIF_MODESET_INPMOD_YCBCR16);

                iss_reg_update(iss, OMAP4_ISS_MEM_ISP_IPIPEIF, IPIPEIF_CFG2,
                               IPIPEIF_CFG2_YUV8, IPIPEIF_CFG2_YUV16);

                break;
        case MEDIA_BUS_FMT_SGRBG10_1X10:
                isif_ccolp = ISIF_CCOLP_CP0_F0_GR |
                        ISIF_CCOLP_CP1_F0_R |
                        ISIF_CCOLP_CP2_F0_B |
                        ISIF_CCOLP_CP3_F0_GB;
                goto cont_raw;
        case MEDIA_BUS_FMT_SRGGB10_1X10:
                isif_ccolp = ISIF_CCOLP_CP0_F0_R |
                        ISIF_CCOLP_CP1_F0_GR |
                        ISIF_CCOLP_CP2_F0_GB |
                        ISIF_CCOLP_CP3_F0_B;
                goto cont_raw;
        case MEDIA_BUS_FMT_SBGGR10_1X10:
                isif_ccolp = ISIF_CCOLP_CP0_F0_B |
                        ISIF_CCOLP_CP1_F0_GB |
                        ISIF_CCOLP_CP2_F0_GR |
                        ISIF_CCOLP_CP3_F0_R;
                goto cont_raw;
        case MEDIA_BUS_FMT_SGBRG10_1X10:
                isif_ccolp = ISIF_CCOLP_CP0_F0_GB |
                        ISIF_CCOLP_CP1_F0_B |
                        ISIF_CCOLP_CP2_F0_R |
                        ISIF_CCOLP_CP3_F0_GR;
cont_raw:
                iss_reg_clr(iss, OMAP4_ISS_MEM_ISP_IPIPEIF, IPIPEIF_CFG2,
                            IPIPEIF_CFG2_YUV16);

                iss_reg_update(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_MODESET,
                               ISIF_MODESET_CCDMD | ISIF_MODESET_INPMOD_MASK |
                               ISIF_MODESET_CCDW_MASK, ISIF_MODESET_INPMOD_RAW |
                               ISIF_MODESET_CCDW_2BIT);

                info = omap4iss_video_format_info(format->code);
                iss_reg_update(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_CGAMMAWD,
                               ISIF_CGAMMAWD_GWDI_MASK,
                               ISIF_CGAMMAWD_GWDI(info->bpp));

                /* Set RAW Bayer pattern */
                iss_reg_write(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_CCOLP,
                              isif_ccolp);
                break;
        }

        iss_reg_write(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_SPH, 0 & ISIF_SPH_MASK);
        iss_reg_write(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_LNH,
                      (format->width - 1) & ISIF_LNH_MASK);
        iss_reg_write(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_LNV,
                      (format->height - 1) & ISIF_LNV_MASK);

        /* Generate ISIF0 on the last line of the image */
        iss_reg_write(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_VDINT(0),
                      format->height - 1);

        /* IPIPEIF_PAD_SOURCE_ISIF_SF */
        format = &ipipeif->formats[IPIPEIF_PAD_SOURCE_ISIF_SF];

        iss_reg_write(iss, OMAP4_ISS_MEM_ISP_ISIF, ISIF_HSIZE,
                      (ipipeif->video_out.bpl_value >> 5) &
                      ISIF_HSIZE_HSIZE_MASK);

        /* IPIPEIF_PAD_SOURCE_VP */
        /* Do nothing? */
}

/* -----------------------------------------------------------------------------
 * Interrupt handling
 */

static void ipipeif_isr_buffer(struct iss_ipipeif_device *ipipeif)
{
        struct iss_buffer *buffer;

        /* The ISIF generates VD0 interrupts even when writes are disabled.
         * deal with it anyway). Disabling the ISIF when no buffer is available
         * is thus not be enough, we need to handle the situation explicitly.
         */
        if (list_empty(&ipipeif->video_out.dmaqueue))
                return;

        ipipeif_write_enable(ipipeif, 0);

        buffer = omap4iss_video_buffer_next(&ipipeif->video_out);
        if (!buffer)
                return;

        ipipeif_set_outaddr(ipipeif, buffer->iss_addr);

        ipipeif_write_enable(ipipeif, 1);
}

/*
 * omap4iss_ipipeif_isr - Configure ipipeif during interframe time.
 * @ipipeif: Pointer to ISP IPIPEIF device.
 * @events: IPIPEIF events
 */
void omap4iss_ipipeif_isr(struct iss_ipipeif_device *ipipeif, u32 events)
{
        if (omap4iss_module_sync_is_stopping(&ipipeif->wait,
                                             &ipipeif->stopping))
                return;

        if ((events & ISP5_IRQ_ISIF_INT(0)) &&
            (ipipeif->output & IPIPEIF_OUTPUT_MEMORY))
                ipipeif_isr_buffer(ipipeif);
}

/* -----------------------------------------------------------------------------
 * ISP video operations
 */

static int ipipeif_video_queue(struct iss_video *video,
                               struct iss_buffer *buffer)
{
        struct iss_ipipeif_device *ipipeif = container_of(video,
                                struct iss_ipipeif_device, video_out);

        if (!(ipipeif->output & IPIPEIF_OUTPUT_MEMORY))
                return -ENODEV;

        ipipeif_set_outaddr(ipipeif, buffer->iss_addr);

        /*
         * If streaming was enabled before there was a buffer queued
         * or underrun happened in the ISR, the hardware was not enabled
         * and DMA queue flag ISS_VIDEO_DMAQUEUE_UNDERRUN is still set.
         * Enable it now.
         */
        if (video->dmaqueue_flags & ISS_VIDEO_DMAQUEUE_UNDERRUN) {
                if (ipipeif->output & IPIPEIF_OUTPUT_MEMORY)
                        ipipeif_write_enable(ipipeif, 1);
                ipipeif_enable(ipipeif, 1);
                iss_video_dmaqueue_flags_clr(video);
        }

        return 0;
}

static const struct iss_video_operations ipipeif_video_ops = {
        .queue = ipipeif_video_queue,
};

/* -----------------------------------------------------------------------------
 * V4L2 subdev operations
 */

#define IPIPEIF_DRV_SUBCLK_MASK (OMAP4_ISS_ISP_SUBCLK_IPIPEIF |\
                                 OMAP4_ISS_ISP_SUBCLK_ISIF)
/*
 * ipipeif_set_stream - Enable/Disable streaming on the IPIPEIF module
 * @sd: ISP IPIPEIF V4L2 subdevice
 * @enable: Enable/disable stream
 */
static int ipipeif_set_stream(struct v4l2_subdev *sd, int enable)
{
        struct iss_ipipeif_device *ipipeif = v4l2_get_subdevdata(sd);
        struct iss_device *iss = to_iss_device(ipipeif);
        struct iss_video *video_out = &ipipeif->video_out;
        int ret = 0;

        if (ipipeif->state == ISS_PIPELINE_STREAM_STOPPED) {
                if (enable == ISS_PIPELINE_STREAM_STOPPED)
                        return 0;

                omap4iss_isp_subclk_enable(iss, IPIPEIF_DRV_SUBCLK_MASK);
        }

        switch (enable) {
        case ISS_PIPELINE_STREAM_CONTINUOUS:

                ipipeif_configure(ipipeif);
                ipipeif_print_status(ipipeif);

                /*
                 * When outputting to memory with no buffer available, let the
                 * buffer queue handler start the hardware. A DMA queue flag
                 * ISS_VIDEO_DMAQUEUE_QUEUED will be set as soon as there is
                 * a buffer available.
                 */
                if (ipipeif->output & IPIPEIF_OUTPUT_MEMORY &&
                    !(video_out->dmaqueue_flags & ISS_VIDEO_DMAQUEUE_QUEUED))
                        break;

                atomic_set(&ipipeif->stopping, 0);
                if (ipipeif->output & IPIPEIF_OUTPUT_MEMORY)
                        ipipeif_write_enable(ipipeif, 1);
                ipipeif_enable(ipipeif, 1);
                iss_video_dmaqueue_flags_clr(video_out);
                break;

        case ISS_PIPELINE_STREAM_STOPPED:
                if (ipipeif->state == ISS_PIPELINE_STREAM_STOPPED)
                        return 0;
                if (omap4iss_module_sync_idle(&sd->entity, &ipipeif->wait,
                                              &ipipeif->stopping))
                        ret = -ETIMEDOUT;

                if (ipipeif->output & IPIPEIF_OUTPUT_MEMORY)
                        ipipeif_write_enable(ipipeif, 0);
                ipipeif_enable(ipipeif, 0);
                omap4iss_isp_subclk_disable(iss, IPIPEIF_DRV_SUBCLK_MASK);
                iss_video_dmaqueue_flags_clr(video_out);
                break;
        }

        ipipeif->state = enable;
        return ret;
}

static struct v4l2_mbus_framefmt *
__ipipeif_get_format(struct iss_ipipeif_device *ipipeif,
                     struct v4l2_subdev_pad_config *cfg, unsigned int pad,
                     enum v4l2_subdev_format_whence which)
{
        if (which == V4L2_SUBDEV_FORMAT_TRY)
                return v4l2_subdev_get_try_format(&ipipeif->subdev, cfg, pad);
        return &ipipeif->formats[pad];
}

/*
 * ipipeif_try_format - Try video format on a pad
 * @ipipeif: ISS IPIPEIF device
 * @cfg: V4L2 subdev pad config
 * @pad: Pad number
 * @fmt: Format
 */
static void
ipipeif_try_format(struct iss_ipipeif_device *ipipeif,
                   struct v4l2_subdev_pad_config *cfg, unsigned int pad,
                   struct v4l2_mbus_framefmt *fmt,
                   enum v4l2_subdev_format_whence which)
{
        struct v4l2_mbus_framefmt *format;
        unsigned int width = fmt->width;
        unsigned int height = fmt->height;
        unsigned int i;

        switch (pad) {
        case IPIPEIF_PAD_SINK:
                /* TODO: If the IPIPEIF output formatter pad is connected
                 * directly to the resizer, only YUV formats can be used.
                 */
                for (i = 0; i < ARRAY_SIZE(ipipeif_fmts); i++) {
                        if (fmt->code == ipipeif_fmts[i])
                                break;
                }

                /* If not found, use SGRBG10 as default */
                if (i >= ARRAY_SIZE(ipipeif_fmts))
                        fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;

                /* Clamp the input size. */
                fmt->width = clamp_t(u32, width, 1, 8192);
                fmt->height = clamp_t(u32, height, 1, 8192);
                break;

        case IPIPEIF_PAD_SOURCE_ISIF_SF:
                format = __ipipeif_get_format(ipipeif, cfg, IPIPEIF_PAD_SINK,
                                              which);
                memcpy(fmt, format, sizeof(*fmt));

                /* The data formatter truncates the number of horizontal output
                 * pixels to a multiple of 16. To avoid clipping data, allow
                 * callers to request an output size bigger than the input size
                 * up to the nearest multiple of 16.
                 */
                fmt->width = clamp_t(u32, width, 32, (fmt->width + 15) & ~15);
                fmt->width &= ~15;
                fmt->height = clamp_t(u32, height, 32, fmt->height);
                break;

        case IPIPEIF_PAD_SOURCE_VP:
                format = __ipipeif_get_format(ipipeif, cfg, IPIPEIF_PAD_SINK,
                                              which);
                memcpy(fmt, format, sizeof(*fmt));

                fmt->width = clamp_t(u32, width, 32, fmt->width);
                fmt->height = clamp_t(u32, height, 32, fmt->height);
                break;
        }

        /* Data is written to memory unpacked, each 10-bit or 12-bit pixel is
         * stored on 2 bytes.
         */
        fmt->colorspace = V4L2_COLORSPACE_SRGB;
        fmt->field = V4L2_FIELD_NONE;
}

/*
 * ipipeif_enum_mbus_code - Handle pixel format enumeration
 * @sd     : pointer to v4l2 subdev structure
 * @cfg    : V4L2 subdev pad config
 * @code   : pointer to v4l2_subdev_mbus_code_enum structure
 * return -EINVAL or zero on success
 */
static int ipipeif_enum_mbus_code(struct v4l2_subdev *sd,
                                  struct v4l2_subdev_pad_config *cfg,
                                  struct v4l2_subdev_mbus_code_enum *code)
{
        struct iss_ipipeif_device *ipipeif = v4l2_get_subdevdata(sd);
        struct v4l2_mbus_framefmt *format;

        switch (code->pad) {
        case IPIPEIF_PAD_SINK:
                if (code->index >= ARRAY_SIZE(ipipeif_fmts))
                        return -EINVAL;

                code->code = ipipeif_fmts[code->index];
                break;

        case IPIPEIF_PAD_SOURCE_ISIF_SF:
        case IPIPEIF_PAD_SOURCE_VP:
                /* No format conversion inside IPIPEIF */
                if (code->index != 0)
                        return -EINVAL;

                format = __ipipeif_get_format(ipipeif, cfg, IPIPEIF_PAD_SINK,
                                              code->which);

                code->code = format->code;
                break;

        default:
                return -EINVAL;
        }

        return 0;
}

static int ipipeif_enum_frame_size(struct v4l2_subdev *sd,
                                   struct v4l2_subdev_pad_config *cfg,
                                   struct v4l2_subdev_frame_size_enum *fse)
{
        struct iss_ipipeif_device *ipipeif = v4l2_get_subdevdata(sd);
        struct v4l2_mbus_framefmt format;

        if (fse->index != 0)
                return -EINVAL;

        format.code = fse->code;
        format.width = 1;
        format.height = 1;
        ipipeif_try_format(ipipeif, cfg, fse->pad, &format, fse->which);
        fse->min_width = format.width;
        fse->min_height = format.height;

        if (format.code != fse->code)
                return -EINVAL;

        format.code = fse->code;
        format.width = -1;
        format.height = -1;
        ipipeif_try_format(ipipeif, cfg, fse->pad, &format, fse->which);
        fse->max_width = format.width;
        fse->max_height = format.height;

        return 0;
}

/*
 * ipipeif_get_format - Retrieve the video format on a pad
 * @sd : ISP IPIPEIF V4L2 subdevice
 * @cfg: V4L2 subdev pad config
 * @fmt: Format
 *
 * Return 0 on success or -EINVAL if the pad is invalid or doesn't correspond
 * to the format type.
 */
static int ipipeif_get_format(struct v4l2_subdev *sd,
                              struct v4l2_subdev_pad_config *cfg,
                              struct v4l2_subdev_format *fmt)
{
        struct iss_ipipeif_device *ipipeif = v4l2_get_subdevdata(sd);
        struct v4l2_mbus_framefmt *format;

        format = __ipipeif_get_format(ipipeif, cfg, fmt->pad, fmt->which);
        if (!format)
                return -EINVAL;

        fmt->format = *format;
        return 0;
}

/*
 * ipipeif_set_format - Set the video format on a pad
 * @sd : ISP IPIPEIF V4L2 subdevice
 * @cfg: V4L2 subdev pad config
 * @fmt: Format
 *
 * Return 0 on success or -EINVAL if the pad is invalid or doesn't correspond
 * to the format type.
 */
static int ipipeif_set_format(struct v4l2_subdev *sd,
                              struct v4l2_subdev_pad_config *cfg,
                              struct v4l2_subdev_format *fmt)
{
        struct iss_ipipeif_device *ipipeif = v4l2_get_subdevdata(sd);
        struct v4l2_mbus_framefmt *format;

        format = __ipipeif_get_format(ipipeif, cfg, fmt->pad, fmt->which);
        if (!format)
                return -EINVAL;

        ipipeif_try_format(ipipeif, cfg, fmt->pad, &fmt->format, fmt->which);
        *format = fmt->format;

        /* Propagate the format from sink to source */
        if (fmt->pad == IPIPEIF_PAD_SINK) {
                format = __ipipeif_get_format(ipipeif, cfg,
                                              IPIPEIF_PAD_SOURCE_ISIF_SF,
                                              fmt->which);
                *format = fmt->format;
                ipipeif_try_format(ipipeif, cfg, IPIPEIF_PAD_SOURCE_ISIF_SF,
                                   format, fmt->which);

                format = __ipipeif_get_format(ipipeif, cfg,
                                              IPIPEIF_PAD_SOURCE_VP,
                                              fmt->which);
                *format = fmt->format;
                ipipeif_try_format(ipipeif, cfg, IPIPEIF_PAD_SOURCE_VP, format,
                                   fmt->which);
        }

        return 0;
}

static int ipipeif_link_validate(struct v4l2_subdev *sd,
                                 struct media_link *link,
                                 struct v4l2_subdev_format *source_fmt,
                                 struct v4l2_subdev_format *sink_fmt)
{
        /* Check if the two ends match */
        if (source_fmt->format.width != sink_fmt->format.width ||
            source_fmt->format.height != sink_fmt->format.height)
                return -EPIPE;

        if (source_fmt->format.code != sink_fmt->format.code)
                return -EPIPE;

        return 0;
}

/*
 * ipipeif_init_formats - Initialize formats on all pads
 * @sd: ISP IPIPEIF V4L2 subdevice
 * @fh: V4L2 subdev file handle
 *
 * Initialize all pad formats with default values. If fh is not NULL, try
 * formats are initialized on the file handle. Otherwise active formats are
 * initialized on the device.
 */
static int ipipeif_init_formats(struct v4l2_subdev *sd,
                                struct v4l2_subdev_fh *fh)
{
        struct v4l2_subdev_format format;

        memset(&format, 0, sizeof(format));
        format.pad = IPIPEIF_PAD_SINK;
        format.which = fh ? V4L2_SUBDEV_FORMAT_TRY : V4L2_SUBDEV_FORMAT_ACTIVE;
        format.format.code = MEDIA_BUS_FMT_SGRBG10_1X10;
        format.format.width = 4096;
        format.format.height = 4096;
        ipipeif_set_format(sd, fh ? fh->pad : NULL, &format);

        return 0;
}

/* V4L2 subdev video operations */
static const struct v4l2_subdev_video_ops ipipeif_v4l2_video_ops = {
        .s_stream = ipipeif_set_stream,
};

/* V4L2 subdev pad operations */
static const struct v4l2_subdev_pad_ops ipipeif_v4l2_pad_ops = {
        .enum_mbus_code = ipipeif_enum_mbus_code,
        .enum_frame_size = ipipeif_enum_frame_size,
        .get_fmt = ipipeif_get_format,
        .set_fmt = ipipeif_set_format,
        .link_validate = ipipeif_link_validate,
};

/* V4L2 subdev operations */
static const struct v4l2_subdev_ops ipipeif_v4l2_ops = {
        .video = &ipipeif_v4l2_video_ops,
        .pad = &ipipeif_v4l2_pad_ops,
};

/* V4L2 subdev internal operations */
static const struct v4l2_subdev_internal_ops ipipeif_v4l2_internal_ops = {
        .open = ipipeif_init_formats,
};

/* -----------------------------------------------------------------------------
 * Media entity operations
 */

/*
 * ipipeif_link_setup - Setup IPIPEIF connections
 * @entity: IPIPEIF media entity
 * @local: Pad at the local end of the link
 * @remote: Pad at the remote end of the link
 * @flags: Link flags
 *
 * return -EINVAL or zero on success
 */
static int ipipeif_link_setup(struct media_entity *entity,
                              const struct media_pad *local,
                              const struct media_pad *remote, u32 flags)
{
        struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
        struct iss_ipipeif_device *ipipeif = v4l2_get_subdevdata(sd);
        struct iss_device *iss = to_iss_device(ipipeif);
        unsigned int index = local->index;

        /* FIXME: this is actually a hack! */
        if (is_media_entity_v4l2_subdev(remote->entity))
                index |= 2 << 16;

        switch (index) {
        case IPIPEIF_PAD_SINK | 2 << 16:
                /* Read from the sensor CSI2a or CSI2b. */
                if (!(flags & MEDIA_LNK_FL_ENABLED)) {
                        ipipeif->input = IPIPEIF_INPUT_NONE;
                        break;
                }

                if (ipipeif->input != IPIPEIF_INPUT_NONE)
                        return -EBUSY;

                if (remote->entity == &iss->csi2a.subdev.entity)
                        ipipeif->input = IPIPEIF_INPUT_CSI2A;
                else if (remote->entity == &iss->csi2b.subdev.entity)
                        ipipeif->input = IPIPEIF_INPUT_CSI2B;

                break;

        case IPIPEIF_PAD_SOURCE_ISIF_SF:
                /* Write to memory */
                if (flags & MEDIA_LNK_FL_ENABLED) {
                        if (ipipeif->output & ~IPIPEIF_OUTPUT_MEMORY)
                                return -EBUSY;
                        ipipeif->output |= IPIPEIF_OUTPUT_MEMORY;
                } else {
                        ipipeif->output &= ~IPIPEIF_OUTPUT_MEMORY;
                }
                break;

        case IPIPEIF_PAD_SOURCE_VP | 2 << 16:
                /* Send to IPIPE/RESIZER */
                if (flags & MEDIA_LNK_FL_ENABLED) {
                        if (ipipeif->output & ~IPIPEIF_OUTPUT_VP)
                                return -EBUSY;
                        ipipeif->output |= IPIPEIF_OUTPUT_VP;
                } else {
                        ipipeif->output &= ~IPIPEIF_OUTPUT_VP;
                }
                break;

        default:
                return -EINVAL;
        }

        return 0;
}

/* media operations */
static const struct media_entity_operations ipipeif_media_ops = {
        .link_setup = ipipeif_link_setup,
        .link_validate = v4l2_subdev_link_validate,
};

/*
 * ipipeif_init_entities - Initialize V4L2 subdev and media entity
 * @ipipeif: ISS ISP IPIPEIF module
 *
 * Return 0 on success and a negative error code on failure.
 */
static int ipipeif_init_entities(struct iss_ipipeif_device *ipipeif)
{
        struct v4l2_subdev *sd = &ipipeif->subdev;
        struct media_pad *pads = ipipeif->pads;
        struct media_entity *me = &sd->entity;
        int ret;

        ipipeif->input = IPIPEIF_INPUT_NONE;

        v4l2_subdev_init(sd, &ipipeif_v4l2_ops);
        sd->internal_ops = &ipipeif_v4l2_internal_ops;
        strlcpy(sd->name, "OMAP4 ISS ISP IPIPEIF", sizeof(sd->name));
        sd->grp_id = BIT(16);   /* group ID for iss subdevs */
        v4l2_set_subdevdata(sd, ipipeif);
        sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;

        pads[IPIPEIF_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
        pads[IPIPEIF_PAD_SOURCE_ISIF_SF].flags = MEDIA_PAD_FL_SOURCE;
        pads[IPIPEIF_PAD_SOURCE_VP].flags = MEDIA_PAD_FL_SOURCE;

        me->ops = &ipipeif_media_ops;
        ret = media_entity_pads_init(me, IPIPEIF_PADS_NUM, pads);
        if (ret < 0)
                return ret;

        ipipeif_init_formats(sd, NULL);

        ipipeif->video_out.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
        ipipeif->video_out.ops = &ipipeif_video_ops;
        ipipeif->video_out.iss = to_iss_device(ipipeif);
        ipipeif->video_out.capture_mem = PAGE_ALIGN(4096 * 4096) * 3;
        ipipeif->video_out.bpl_alignment = 32;
        ipipeif->video_out.bpl_zero_padding = 1;
        ipipeif->video_out.bpl_max = 0x1ffe0;

        return omap4iss_video_init(&ipipeif->video_out, "ISP IPIPEIF");
}

void omap4iss_ipipeif_unregister_entities(struct iss_ipipeif_device *ipipeif)
{
        v4l2_device_unregister_subdev(&ipipeif->subdev);
        omap4iss_video_unregister(&ipipeif->video_out);
}

int omap4iss_ipipeif_register_entities(struct iss_ipipeif_device *ipipeif,
                                       struct v4l2_device *vdev)
{
        int ret;

        /* Register the subdev and video node. */
        ret = v4l2_device_register_subdev(vdev, &ipipeif->subdev);
        if (ret < 0)
                goto error;

        ret = omap4iss_video_register(&ipipeif->video_out, vdev);
        if (ret < 0)
                goto error;

        return 0;

error:
        omap4iss_ipipeif_unregister_entities(ipipeif);
        return ret;
}

/* -----------------------------------------------------------------------------
 * ISP IPIPEIF initialisation and cleanup
 */

/*
 * omap4iss_ipipeif_init - IPIPEIF module initialization.
 * @iss: Device pointer specific to the OMAP4 ISS.
 *
 * TODO: Get the initialisation values from platform data.
 *
 * Return 0 on success or a negative error code otherwise.
 */
int omap4iss_ipipeif_init(struct iss_device *iss)
{
        struct iss_ipipeif_device *ipipeif = &iss->ipipeif;

        ipipeif->state = ISS_PIPELINE_STREAM_STOPPED;
        init_waitqueue_head(&ipipeif->wait);

        return ipipeif_init_entities(ipipeif);
}

/*
 * omap4iss_ipipeif_create_links() - IPIPEIF pads links creation
 * @iss: Pointer to ISS device
 *
 * return negative error code or zero on success
 */
int omap4iss_ipipeif_create_links(struct iss_device *iss)
{
        struct iss_ipipeif_device *ipipeif = &iss->ipipeif;

        /* Connect the IPIPEIF subdev to the video node. */
        return media_create_pad_link(&ipipeif->subdev.entity,
                                     IPIPEIF_PAD_SOURCE_ISIF_SF,
                                     &ipipeif->video_out.video.entity, 0, 0);
}

/*
 * omap4iss_ipipeif_cleanup - IPIPEIF module cleanup.
 * @iss: Device pointer specific to the OMAP4 ISS.
 */
void omap4iss_ipipeif_cleanup(struct iss_device *iss)
{
        struct iss_ipipeif_device *ipipeif = &iss->ipipeif;

        media_entity_cleanup(&ipipeif->subdev.entity);
}