/*
 * SuperH Mobile LCDC Framebuffer
 *
 * Copyright (c) 2008 Magnus Damm
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#include <linux/atomic.h>
#include <linux/backlight.h>
#include <linux/clk.h>
#include <linux/console.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioctl.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/videodev2.h>
#include <linux/vmalloc.h>

#include <video/sh_mobile_lcdc.h>
#include <video/sh_mobile_meram.h>

#include "sh_mobile_lcdcfb.h"

#define SIDE_B_OFFSET 0x1000
#define MIRROR_OFFSET 0x2000

#define MAX_XRES 1920
#define MAX_YRES 1080

struct sh_mobile_lcdc_priv {
        void __iomem *base;
        int irq;
        atomic_t hw_usecnt;
        struct device *dev;
        struct clk *dot_clk;
        unsigned long lddckr;
        struct sh_mobile_lcdc_chan ch[2];
        struct notifier_block notifier;
        int started;
        int forced_fourcc; /* 2 channel LCDC must share fourcc setting */
        struct sh_mobile_meram_info *meram_dev;
};

/* -----------------------------------------------------------------------------
 * Registers access
 */

static unsigned long lcdc_offs_mainlcd[NR_CH_REGS] = {
        [LDDCKPAT1R] = 0x400,
        [LDDCKPAT2R] = 0x404,
        [LDMT1R] = 0x418,
        [LDMT2R] = 0x41c,
        [LDMT3R] = 0x420,
        [LDDFR] = 0x424,
        [LDSM1R] = 0x428,
        [LDSM2R] = 0x42c,
        [LDSA1R] = 0x430,
        [LDSA2R] = 0x434,
        [LDMLSR] = 0x438,
        [LDHCNR] = 0x448,
        [LDHSYNR] = 0x44c,
        [LDVLNR] = 0x450,
        [LDVSYNR] = 0x454,
        [LDPMR] = 0x460,
        [LDHAJR] = 0x4a0,
};

static unsigned long lcdc_offs_sublcd[NR_CH_REGS] = {
        [LDDCKPAT1R] = 0x408,
        [LDDCKPAT2R] = 0x40c,
        [LDMT1R] = 0x600,
        [LDMT2R] = 0x604,
        [LDMT3R] = 0x608,
        [LDDFR] = 0x60c,
        [LDSM1R] = 0x610,
        [LDSM2R] = 0x614,
        [LDSA1R] = 0x618,
        [LDMLSR] = 0x620,
        [LDHCNR] = 0x624,
        [LDHSYNR] = 0x628,
        [LDVLNR] = 0x62c,
        [LDVSYNR] = 0x630,
        [LDPMR] = 0x63c,
};

static bool banked(int reg_nr)
{
        switch (reg_nr) {
        case LDMT1R:
        case LDMT2R:
        case LDMT3R:
        case LDDFR:
        case LDSM1R:
        case LDSA1R:
        case LDSA2R:
        case LDMLSR:
        case LDHCNR:
        case LDHSYNR:
        case LDVLNR:
        case LDVSYNR:
                return true;
        }
        return false;
}

static int lcdc_chan_is_sublcd(struct sh_mobile_lcdc_chan *chan)
{
        return chan->cfg->chan == LCDC_CHAN_SUBLCD;
}

static void lcdc_write_chan(struct sh_mobile_lcdc_chan *chan,
                            int reg_nr, unsigned long data)
{
        iowrite32(data, chan->lcdc->base + chan->reg_offs[reg_nr]);
        if (banked(reg_nr))
                iowrite32(data, chan->lcdc->base + chan->reg_offs[reg_nr] +
                          SIDE_B_OFFSET);
}

static void lcdc_write_chan_mirror(struct sh_mobile_lcdc_chan *chan,
                            int reg_nr, unsigned long data)
{
        iowrite32(data, chan->lcdc->base + chan->reg_offs[reg_nr] +
                  MIRROR_OFFSET);
}

static unsigned long lcdc_read_chan(struct sh_mobile_lcdc_chan *chan,
                                    int reg_nr)
{
        return ioread32(chan->lcdc->base + chan->reg_offs[reg_nr]);
}

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

static unsigned long lcdc_read(struct sh_mobile_lcdc_priv *priv,
                               unsigned long reg_offs)
{
        return ioread32(priv->base + reg_offs);
}

static void lcdc_wait_bit(struct sh_mobile_lcdc_priv *priv,
                          unsigned long reg_offs,
                          unsigned long mask, unsigned long until)
{
        while ((lcdc_read(priv, reg_offs) & mask) != until)
                cpu_relax();
}

/* -----------------------------------------------------------------------------
 * Clock management
 */

static void sh_mobile_lcdc_clk_on(struct sh_mobile_lcdc_priv *priv)
{
        if (atomic_inc_and_test(&priv->hw_usecnt)) {
                if (priv->dot_clk)
                        clk_enable(priv->dot_clk);
                pm_runtime_get_sync(priv->dev);
                if (priv->meram_dev && priv->meram_dev->pdev)
                        pm_runtime_get_sync(&priv->meram_dev->pdev->dev);
        }
}

static void sh_mobile_lcdc_clk_off(struct sh_mobile_lcdc_priv *priv)
{
        if (atomic_sub_return(1, &priv->hw_usecnt) == -1) {
                if (priv->meram_dev && priv->meram_dev->pdev)
                        pm_runtime_put_sync(&priv->meram_dev->pdev->dev);
                pm_runtime_put(priv->dev);
                if (priv->dot_clk)
                        clk_disable(priv->dot_clk);
        }
}

static int sh_mobile_lcdc_setup_clocks(struct sh_mobile_lcdc_priv *priv,
                                       int clock_source)
{
        struct clk *clk;
        char *str;

        switch (clock_source) {
        case LCDC_CLK_BUS:
                str = "bus_clk";
                priv->lddckr = LDDCKR_ICKSEL_BUS;
                break;
        case LCDC_CLK_PERIPHERAL:
                str = "peripheral_clk";
                priv->lddckr = LDDCKR_ICKSEL_MIPI;
                break;
        case LCDC_CLK_EXTERNAL:
                str = NULL;
                priv->lddckr = LDDCKR_ICKSEL_HDMI;
                break;
        default:
                return -EINVAL;
        }

        if (str == NULL)
                return 0;

        clk = clk_get(priv->dev, str);
        if (IS_ERR(clk)) {
                dev_err(priv->dev, "cannot get dot clock %s\n", str);
                return PTR_ERR(clk);
        }

        priv->dot_clk = clk;
        return 0;
}

/* -----------------------------------------------------------------------------
 * Display, panel and deferred I/O
 */

static void lcdc_sys_write_index(void *handle, unsigned long data)
{
        struct sh_mobile_lcdc_chan *ch = handle;

        lcdc_write(ch->lcdc, _LDDWD0R, data | LDDWDxR_WDACT);
        lcdc_wait_bit(ch->lcdc, _LDSR, LDSR_AS, 0);
        lcdc_write(ch->lcdc, _LDDWAR, LDDWAR_WA |
                   (lcdc_chan_is_sublcd(ch) ? 2 : 0));
        lcdc_wait_bit(ch->lcdc, _LDSR, LDSR_AS, 0);
}

static void lcdc_sys_write_data(void *handle, unsigned long data)
{
        struct sh_mobile_lcdc_chan *ch = handle;

        lcdc_write(ch->lcdc, _LDDWD0R, data | LDDWDxR_WDACT | LDDWDxR_RSW);
        lcdc_wait_bit(ch->lcdc, _LDSR, LDSR_AS, 0);
        lcdc_write(ch->lcdc, _LDDWAR, LDDWAR_WA |
                   (lcdc_chan_is_sublcd(ch) ? 2 : 0));
        lcdc_wait_bit(ch->lcdc, _LDSR, LDSR_AS, 0);
}

static unsigned long lcdc_sys_read_data(void *handle)
{
        struct sh_mobile_lcdc_chan *ch = handle;

        lcdc_write(ch->lcdc, _LDDRDR, LDDRDR_RSR);
        lcdc_wait_bit(ch->lcdc, _LDSR, LDSR_AS, 0);
        lcdc_write(ch->lcdc, _LDDRAR, LDDRAR_RA |
                   (lcdc_chan_is_sublcd(ch) ? 2 : 0));
        udelay(1);
        lcdc_wait_bit(ch->lcdc, _LDSR, LDSR_AS, 0);

        return lcdc_read(ch->lcdc, _LDDRDR) & LDDRDR_DRD_MASK;
}

struct sh_mobile_lcdc_sys_bus_ops sh_mobile_lcdc_sys_bus_ops = {
        lcdc_sys_write_index,
        lcdc_sys_write_data,
        lcdc_sys_read_data,
};

static int sh_mobile_lcdc_sginit(struct fb_info *info,
                                  struct list_head *pagelist)
{
        struct sh_mobile_lcdc_chan *ch = info->par;
        unsigned int nr_pages_max = ch->fb_size >> PAGE_SHIFT;
        struct page *page;
        int nr_pages = 0;

        sg_init_table(ch->sglist, nr_pages_max);

        list_for_each_entry(page, pagelist, lru)
                sg_set_page(&ch->sglist[nr_pages++], page, PAGE_SIZE, 0);

        return nr_pages;
}

static void sh_mobile_lcdc_deferred_io(struct fb_info *info,
                                       struct list_head *pagelist)
{
        struct sh_mobile_lcdc_chan *ch = info->par;
        const struct sh_mobile_lcdc_panel_cfg *panel = &ch->cfg->panel_cfg;

        /* enable clocks before accessing hardware */
        sh_mobile_lcdc_clk_on(ch->lcdc);

        /*
         * It's possible to get here without anything on the pagelist via
         * sh_mobile_lcdc_deferred_io_touch() or via a userspace fsync()
         * invocation. In the former case, the acceleration routines are
         * stepped in to when using the framebuffer console causing the
         * workqueue to be scheduled without any dirty pages on the list.
         *
         * Despite this, a panel update is still needed given that the
         * acceleration routines have their own methods for writing in
         * that still need to be updated.
         *
         * The fsync() and empty pagelist case could be optimized for,
         * but we don't bother, as any application exhibiting such
         * behaviour is fundamentally broken anyways.
         */
        if (!list_empty(pagelist)) {
                unsigned int nr_pages = sh_mobile_lcdc_sginit(info, pagelist);

                /* trigger panel update */
                dma_map_sg(ch->lcdc->dev, ch->sglist, nr_pages, DMA_TO_DEVICE);
                if (panel->start_transfer)
                        panel->start_transfer(ch, &sh_mobile_lcdc_sys_bus_ops);
                lcdc_write_chan(ch, LDSM2R, LDSM2R_OSTRG);
                dma_unmap_sg(ch->lcdc->dev, ch->sglist, nr_pages,
                             DMA_TO_DEVICE);
        } else {
                if (panel->start_transfer)
                        panel->start_transfer(ch, &sh_mobile_lcdc_sys_bus_ops);
                lcdc_write_chan(ch, LDSM2R, LDSM2R_OSTRG);
        }
}

static void sh_mobile_lcdc_deferred_io_touch(struct fb_info *info)
{
        struct fb_deferred_io *fbdefio = info->fbdefio;

        if (fbdefio)
                schedule_delayed_work(&info->deferred_work, fbdefio->delay);
}

static void sh_mobile_lcdc_display_on(struct sh_mobile_lcdc_chan *ch)
{
        const struct sh_mobile_lcdc_panel_cfg *panel = &ch->cfg->panel_cfg;

        if (ch->tx_dev) {
                int ret;

                ret = ch->tx_dev->ops->display_on(ch->tx_dev);
                if (ret < 0)
                        return;

                if (ret == SH_MOBILE_LCDC_DISPLAY_DISCONNECTED)
                        ch->info->state = FBINFO_STATE_SUSPENDED;
        }

        /* HDMI must be enabled before LCDC configuration */
        if (panel->display_on)
                panel->display_on();
}

static void sh_mobile_lcdc_display_off(struct sh_mobile_lcdc_chan *ch)
{
        const struct sh_mobile_lcdc_panel_cfg *panel = &ch->cfg->panel_cfg;

        if (panel->display_off)
                panel->display_off();

        if (ch->tx_dev)
                ch->tx_dev->ops->display_off(ch->tx_dev);
}

static bool
sh_mobile_lcdc_must_reconfigure(struct sh_mobile_lcdc_chan *ch,
                                const struct fb_videomode *new_mode)
{
        dev_dbg(ch->info->dev, "Old %ux%u, new %ux%u\n",
                ch->display.mode.xres, ch->display.mode.yres,
                new_mode->xres, new_mode->yres);

        /* It can be a different monitor with an equal video-mode */
        if (fb_mode_is_equal(&ch->display.mode, new_mode))
                return false;

        dev_dbg(ch->info->dev, "Switching %u -> %u lines\n",
                ch->display.mode.yres, new_mode->yres);
        ch->display.mode = *new_mode;

        return true;
}

static int sh_mobile_check_var(struct fb_var_screeninfo *var,
                               struct fb_info *info);

static int sh_mobile_lcdc_display_notify(struct sh_mobile_lcdc_chan *ch,
                                         enum sh_mobile_lcdc_entity_event event,
                                         const struct fb_videomode *mode,
                                         const struct fb_monspecs *monspec)
{
        struct fb_info *info = ch->info;
        struct fb_var_screeninfo var;
        int ret = 0;

        switch (event) {
        case SH_MOBILE_LCDC_EVENT_DISPLAY_CONNECT:
                /* HDMI plug in */
                if (lock_fb_info(info)) {
                        console_lock();

                        ch->display.width = monspec->max_x * 10;
                        ch->display.height = monspec->max_y * 10;

                        if (!sh_mobile_lcdc_must_reconfigure(ch, mode) &&
                            info->state == FBINFO_STATE_RUNNING) {
                                /* First activation with the default monitor.
                                 * Just turn on, if we run a resume here, the
                                 * logo disappears.
                                 */
                                info->var.width = monspec->max_x * 10;
                                info->var.height = monspec->max_y * 10;
                                sh_mobile_lcdc_display_on(ch);
                        } else {
                                /* New monitor or have to wake up */
                                fb_set_suspend(info, 0);
                        }

                        console_unlock();
                        unlock_fb_info(info);
                }
                break;

        case SH_MOBILE_LCDC_EVENT_DISPLAY_DISCONNECT:
                /* HDMI disconnect */
                if (lock_fb_info(info)) {
                        console_lock();
                        fb_set_suspend(info, 1);
                        console_unlock();
                        unlock_fb_info(info);
                }
                break;

        case SH_MOBILE_LCDC_EVENT_DISPLAY_MODE:
                /* Validate a proposed new mode */
                fb_videomode_to_var(&var, mode);
                var.bits_per_pixel = info->var.bits_per_pixel;
                var.grayscale = info->var.grayscale;
                ret = sh_mobile_check_var(&var, info);
                break;
        }

        return ret;
}

/* -----------------------------------------------------------------------------
 * Format helpers
 */

struct sh_mobile_lcdc_format_info {
        u32 fourcc;
        unsigned int bpp;
        bool yuv;
        u32 lddfr;
};

static const struct sh_mobile_lcdc_format_info sh_mobile_format_infos[] = {
        {
                .fourcc = V4L2_PIX_FMT_RGB565,
                .bpp = 16,
                .yuv = false,
                .lddfr = LDDFR_PKF_RGB16,
        }, {
                .fourcc = V4L2_PIX_FMT_BGR24,
                .bpp = 24,
                .yuv = false,
                .lddfr = LDDFR_PKF_RGB24,
        }, {
                .fourcc = V4L2_PIX_FMT_BGR32,
                .bpp = 32,
                .yuv = false,
                .lddfr = LDDFR_PKF_ARGB32,
        }, {
                .fourcc = V4L2_PIX_FMT_NV12,
                .bpp = 12,
                .yuv = true,
                .lddfr = LDDFR_CC | LDDFR_YF_420,
        }, {
                .fourcc = V4L2_PIX_FMT_NV21,
                .bpp = 12,
                .yuv = true,
                .lddfr = LDDFR_CC | LDDFR_YF_420,
        }, {
                .fourcc = V4L2_PIX_FMT_NV16,
                .bpp = 16,
                .yuv = true,
                .lddfr = LDDFR_CC | LDDFR_YF_422,
        }, {
                .fourcc = V4L2_PIX_FMT_NV61,
                .bpp = 16,
                .yuv = true,
                .lddfr = LDDFR_CC | LDDFR_YF_422,
        }, {
                .fourcc = V4L2_PIX_FMT_NV24,
                .bpp = 24,
                .yuv = true,
                .lddfr = LDDFR_CC | LDDFR_YF_444,
        }, {
                .fourcc = V4L2_PIX_FMT_NV42,
                .bpp = 24,
                .yuv = true,
                .lddfr = LDDFR_CC | LDDFR_YF_444,
        },
};

static const struct sh_mobile_lcdc_format_info *
sh_mobile_format_info(u32 fourcc)
{
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(sh_mobile_format_infos); ++i) {
                if (sh_mobile_format_infos[i].fourcc == fourcc)
                        return &sh_mobile_format_infos[i];
        }

        return NULL;
}

static int sh_mobile_format_fourcc(const struct fb_var_screeninfo *var)
{
        if (var->grayscale > 1)
                return var->grayscale;

        switch (var->bits_per_pixel) {
        case 16:
                return V4L2_PIX_FMT_RGB565;
        case 24:
                return V4L2_PIX_FMT_BGR24;
        case 32:
                return V4L2_PIX_FMT_BGR32;
        default:
                return 0;
        }
}

static int sh_mobile_format_is_fourcc(const struct fb_var_screeninfo *var)
{
        return var->grayscale > 1;
}

/* -----------------------------------------------------------------------------
 * Start, stop and IRQ
 */

static irqreturn_t sh_mobile_lcdc_irq(int irq, void *data)
{
        struct sh_mobile_lcdc_priv *priv = data;
        struct sh_mobile_lcdc_chan *ch;
        unsigned long ldintr;
        int is_sub;
        int k;

        /* Acknowledge interrupts and disable further VSYNC End IRQs. */
        ldintr = lcdc_read(priv, _LDINTR);
        lcdc_write(priv, _LDINTR, (ldintr ^ LDINTR_STATUS_MASK) & ~LDINTR_VEE);

        /* figure out if this interrupt is for main or sub lcd */
        is_sub = (lcdc_read(priv, _LDSR) & LDSR_MSS) ? 1 : 0;

        /* wake up channel and disable clocks */
        for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
                ch = &priv->ch[k];

                if (!ch->enabled)
                        continue;

                /* Frame End */
                if (ldintr & LDINTR_FS) {
                        if (is_sub == lcdc_chan_is_sublcd(ch)) {
                                ch->frame_end = 1;
                                wake_up(&ch->frame_end_wait);

                                sh_mobile_lcdc_clk_off(priv);
                        }
                }

                /* VSYNC End */
                if (ldintr & LDINTR_VES)
                        complete(&ch->vsync_completion);
        }

        return IRQ_HANDLED;
}

static int sh_mobile_wait_for_vsync(struct sh_mobile_lcdc_chan *ch)
{
        unsigned long ldintr;
        int ret;

        /* Enable VSync End interrupt and be careful not to acknowledge any
         * pending interrupt.
         */
        ldintr = lcdc_read(ch->lcdc, _LDINTR);
        ldintr |= LDINTR_VEE | LDINTR_STATUS_MASK;
        lcdc_write(ch->lcdc, _LDINTR, ldintr);

        ret = wait_for_completion_interruptible_timeout(&ch->vsync_completion,
                                                        msecs_to_jiffies(100));
        if (!ret)
                return -ETIMEDOUT;

        return 0;
}

static void sh_mobile_lcdc_start_stop(struct sh_mobile_lcdc_priv *priv,
                                      int start)
{
        unsigned long tmp = lcdc_read(priv, _LDCNT2R);
        int k;

        /* start or stop the lcdc */
        if (start)
                lcdc_write(priv, _LDCNT2R, tmp | LDCNT2R_DO);
        else
                lcdc_write(priv, _LDCNT2R, tmp & ~LDCNT2R_DO);

        /* wait until power is applied/stopped on all channels */
        for (k = 0; k < ARRAY_SIZE(priv->ch); k++)
                if (lcdc_read(priv, _LDCNT2R) & priv->ch[k].enabled)
                        while (1) {
                                tmp = lcdc_read_chan(&priv->ch[k], LDPMR)
                                    & LDPMR_LPS;
                                if (start && tmp == LDPMR_LPS)
                                        break;
                                if (!start && tmp == 0)
                                        break;
                                cpu_relax();
                        }

        if (!start)
                lcdc_write(priv, _LDDCKSTPR, 1); /* stop dotclock */
}

static void sh_mobile_lcdc_geometry(struct sh_mobile_lcdc_chan *ch)
{
        const struct fb_var_screeninfo *var = &ch->info->var;
        const struct fb_videomode *mode = &ch->display.mode;
        unsigned long h_total, hsync_pos, display_h_total;
        u32 tmp;

        tmp = ch->ldmt1r_value;
        tmp |= (var->sync & FB_SYNC_VERT_HIGH_ACT) ? 0 : LDMT1R_VPOL;
        tmp |= (var->sync & FB_SYNC_HOR_HIGH_ACT) ? 0 : LDMT1R_HPOL;
        tmp |= (ch->cfg->flags & LCDC_FLAGS_DWPOL) ? LDMT1R_DWPOL : 0;
        tmp |= (ch->cfg->flags & LCDC_FLAGS_DIPOL) ? LDMT1R_DIPOL : 0;
        tmp |= (ch->cfg->flags & LCDC_FLAGS_DAPOL) ? LDMT1R_DAPOL : 0;
        tmp |= (ch->cfg->flags & LCDC_FLAGS_HSCNT) ? LDMT1R_HSCNT : 0;
        tmp |= (ch->cfg->flags & LCDC_FLAGS_DWCNT) ? LDMT1R_DWCNT : 0;
        lcdc_write_chan(ch, LDMT1R, tmp);

        /* setup SYS bus */
        lcdc_write_chan(ch, LDMT2R, ch->cfg->sys_bus_cfg.ldmt2r);
        lcdc_write_chan(ch, LDMT3R, ch->cfg->sys_bus_cfg.ldmt3r);

        /* horizontal configuration */
        h_total = mode->xres + mode->hsync_len + mode->left_margin
                + mode->right_margin;
        tmp = h_total / 8; /* HTCN */
        tmp |= (min(mode->xres, ch->xres) / 8) << 16; /* HDCN */
        lcdc_write_chan(ch, LDHCNR, tmp);

        hsync_pos = mode->xres + mode->right_margin;
        tmp = hsync_pos / 8; /* HSYNP */
        tmp |= (mode->hsync_len / 8) << 16; /* HSYNW */
        lcdc_write_chan(ch, LDHSYNR, tmp);

        /* vertical configuration */
        tmp = mode->yres + mode->vsync_len + mode->upper_margin
            + mode->lower_margin; /* VTLN */
        tmp |= min(mode->yres, ch->yres) << 16; /* VDLN */
        lcdc_write_chan(ch, LDVLNR, tmp);

        tmp = mode->yres + mode->lower_margin; /* VSYNP */
        tmp |= mode->vsync_len << 16; /* VSYNW */
        lcdc_write_chan(ch, LDVSYNR, tmp);

        /* Adjust horizontal synchronisation for HDMI */
        display_h_total = mode->xres + mode->hsync_len + mode->left_margin
                        + mode->right_margin;
        tmp = ((mode->xres & 7) << 24) | ((display_h_total & 7) << 16)
            | ((mode->hsync_len & 7) << 8) | (hsync_pos & 7);
        lcdc_write_chan(ch, LDHAJR, tmp);
}

/*
 * __sh_mobile_lcdc_start - Configure and tart the LCDC
 * @priv: LCDC device
 *
 * Configure all enabled channels and start the LCDC device. All external
 * devices (clocks, MERAM, panels, ...) are not touched by this function.
 */
static void __sh_mobile_lcdc_start(struct sh_mobile_lcdc_priv *priv)
{
        struct sh_mobile_lcdc_chan *ch;
        unsigned long tmp;
        int k, m;

        /* Enable LCDC channels. Read data from external memory, avoid using the
         * BEU for now.
         */
        lcdc_write(priv, _LDCNT2R, priv->ch[0].enabled | priv->ch[1].enabled);

        /* Stop the LCDC first and disable all interrupts. */
        sh_mobile_lcdc_start_stop(priv, 0);
        lcdc_write(priv, _LDINTR, 0);

        /* Configure power supply, dot clocks and start them. */
        tmp = priv->lddckr;
        for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
                ch = &priv->ch[k];
                if (!ch->enabled)
                        continue;

                /* Power supply */
                lcdc_write_chan(ch, LDPMR, 0);

                m = ch->cfg->clock_divider;
                if (!m)
                        continue;

                /* FIXME: sh7724 can only use 42, 48, 54 and 60 for the divider
                 * denominator.
                 */
                lcdc_write_chan(ch, LDDCKPAT1R, 0);
                lcdc_write_chan(ch, LDDCKPAT2R, (1 << (m/2)) - 1);

                if (m == 1)
                        m = LDDCKR_MOSEL;
                tmp |= m << (lcdc_chan_is_sublcd(ch) ? 8 : 0);
        }

        lcdc_write(priv, _LDDCKR, tmp);
        lcdc_write(priv, _LDDCKSTPR, 0);
        lcdc_wait_bit(priv, _LDDCKSTPR, ~0, 0);

        /* Setup geometry, format, frame buffer memory and operation mode. */
        for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
                ch = &priv->ch[k];
                if (!ch->enabled)
                        continue;

                sh_mobile_lcdc_geometry(ch);

                tmp = ch->format->lddfr;

                if (ch->format->yuv) {
                        switch (ch->colorspace) {
                        case V4L2_COLORSPACE_REC709:
                                tmp |= LDDFR_CF1;
                                break;
                        case V4L2_COLORSPACE_JPEG:
                                tmp |= LDDFR_CF0;
                                break;
                        }
                }

                lcdc_write_chan(ch, LDDFR, tmp);
                lcdc_write_chan(ch, LDMLSR, ch->pitch);
                lcdc_write_chan(ch, LDSA1R, ch->base_addr_y);
                if (ch->format->yuv)
                        lcdc_write_chan(ch, LDSA2R, ch->base_addr_c);

                /* When using deferred I/O mode, configure the LCDC for one-shot
                 * operation and enable the frame end interrupt. Otherwise use
                 * continuous read mode.
                 */
                if (ch->ldmt1r_value & LDMT1R_IFM &&
                    ch->cfg->sys_bus_cfg.deferred_io_msec) {
                        lcdc_write_chan(ch, LDSM1R, LDSM1R_OS);
                        lcdc_write(priv, _LDINTR, LDINTR_FE);
                } else {
                        lcdc_write_chan(ch, LDSM1R, 0);
                }
        }

        /* Word and long word swap. */
        switch (priv->ch[0].format->fourcc) {
        case V4L2_PIX_FMT_RGB565:
        case V4L2_PIX_FMT_NV21:
        case V4L2_PIX_FMT_NV61:
        case V4L2_PIX_FMT_NV42:
                tmp = LDDDSR_LS | LDDDSR_WS;
                break;
        case V4L2_PIX_FMT_BGR24:
        case V4L2_PIX_FMT_NV12:
        case V4L2_PIX_FMT_NV16:
        case V4L2_PIX_FMT_NV24:
                tmp = LDDDSR_LS | LDDDSR_WS | LDDDSR_BS;
                break;
        case V4L2_PIX_FMT_BGR32:
        default:
                tmp = LDDDSR_LS;
                break;
        }
        lcdc_write(priv, _LDDDSR, tmp);

        /* Enable the display output. */
        lcdc_write(priv, _LDCNT1R, LDCNT1R_DE);
        sh_mobile_lcdc_start_stop(priv, 1);
        priv->started = 1;
}

static int sh_mobile_lcdc_start(struct sh_mobile_lcdc_priv *priv)
{
        struct sh_mobile_meram_info *mdev = priv->meram_dev;
        struct sh_mobile_lcdc_chan *ch;
        unsigned long tmp;
        int ret;
        int k;

        /* enable clocks before accessing the hardware */
        for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
                if (priv->ch[k].enabled)
                        sh_mobile_lcdc_clk_on(priv);
        }

        /* reset */
        lcdc_write(priv, _LDCNT2R, lcdc_read(priv, _LDCNT2R) | LDCNT2R_BR);
        lcdc_wait_bit(priv, _LDCNT2R, LDCNT2R_BR, 0);

        for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
                const struct sh_mobile_lcdc_panel_cfg *panel;

                ch = &priv->ch[k];
                if (!ch->enabled)
                        continue;

                panel = &ch->cfg->panel_cfg;
                if (panel->setup_sys) {
                        ret = panel->setup_sys(ch, &sh_mobile_lcdc_sys_bus_ops);
                        if (ret)
                                return ret;
                }
        }

        /* Compute frame buffer base address and pitch for each channel. */
        for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
                int pixelformat;
                void *meram;

                ch = &priv->ch[k];
                if (!ch->enabled)
                        continue;

                ch->base_addr_y = ch->dma_handle;
                ch->base_addr_c = ch->base_addr_y + ch->xres * ch->yres_virtual;

                /* Enable MERAM if possible. */
                if (mdev == NULL || mdev->ops == NULL ||
                    ch->cfg->meram_cfg == NULL)
                        continue;

                /* we need to de-init configured ICBs before we can
                 * re-initialize them.
                 */
                if (ch->meram) {
                        mdev->ops->meram_unregister(mdev, ch->meram);
                        ch->meram = NULL;
                }

                switch (ch->format->fourcc) {
                case V4L2_PIX_FMT_NV12:
                case V4L2_PIX_FMT_NV21:
                case V4L2_PIX_FMT_NV16:
                case V4L2_PIX_FMT_NV61:
                        pixelformat = SH_MOBILE_MERAM_PF_NV;
                        break;
                case V4L2_PIX_FMT_NV24:
                case V4L2_PIX_FMT_NV42:
                        pixelformat = SH_MOBILE_MERAM_PF_NV24;
                        break;
                case V4L2_PIX_FMT_RGB565:
                case V4L2_PIX_FMT_BGR24:
                case V4L2_PIX_FMT_BGR32:
                default:
                        pixelformat = SH_MOBILE_MERAM_PF_RGB;
                        break;
                }

                meram = mdev->ops->meram_register(mdev, ch->cfg->meram_cfg,
                                        ch->pitch, ch->yres, pixelformat,
                                        &ch->pitch);
                if (!IS_ERR(meram)) {
                        mdev->ops->meram_update(mdev, meram,
                                        ch->base_addr_y, ch->base_addr_c,
                                        &ch->base_addr_y, &ch->base_addr_c);
                        ch->meram = meram;
                }
        }

        /* Start the LCDC. */
        __sh_mobile_lcdc_start(priv);

        /* Setup deferred I/O, tell the board code to enable the panels, and
         * turn backlight on.
         */
        for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
                ch = &priv->ch[k];
                if (!ch->enabled)
                        continue;

                tmp = ch->cfg->sys_bus_cfg.deferred_io_msec;
                if (ch->ldmt1r_value & LDMT1R_IFM && tmp) {
                        ch->defio.deferred_io = sh_mobile_lcdc_deferred_io;
                        ch->defio.delay = msecs_to_jiffies(tmp);
                        ch->info->fbdefio = &ch->defio;
                        fb_deferred_io_init(ch->info);
                }

                sh_mobile_lcdc_display_on(ch);

                if (ch->bl) {
                        ch->bl->props.power = FB_BLANK_UNBLANK;
                        backlight_update_status(ch->bl);
                }
        }

        return 0;
}

static void sh_mobile_lcdc_stop(struct sh_mobile_lcdc_priv *priv)
{
        struct sh_mobile_lcdc_chan *ch;
        int k;

        /* clean up deferred io and ask board code to disable panel */
        for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
                ch = &priv->ch[k];
                if (!ch->enabled)
                        continue;

                /* deferred io mode:
                 * flush frame, and wait for frame end interrupt
                 * clean up deferred io and enable clock
                 */
                if (ch->info && ch->info->fbdefio) {
                        ch->frame_end = 0;
                        schedule_delayed_work(&ch->info->deferred_work, 0);
                        wait_event(ch->frame_end_wait, ch->frame_end);
                        fb_deferred_io_cleanup(ch->info);
                        ch->info->fbdefio = NULL;
                        sh_mobile_lcdc_clk_on(priv);
                }

                if (ch->bl) {
                        ch->bl->props.power = FB_BLANK_POWERDOWN;
                        backlight_update_status(ch->bl);
                }

                sh_mobile_lcdc_display_off(ch);

                /* disable the meram */
                if (ch->meram) {
                        struct sh_mobile_meram_info *mdev;
                        mdev = priv->meram_dev;
                        mdev->ops->meram_unregister(mdev, ch->meram);
                        ch->meram = 0;
                }

        }

        /* stop the lcdc */
        if (priv->started) {
                sh_mobile_lcdc_start_stop(priv, 0);
                priv->started = 0;
        }

        /* stop clocks */
        for (k = 0; k < ARRAY_SIZE(priv->ch); k++)
                if (priv->ch[k].enabled)
                        sh_mobile_lcdc_clk_off(priv);
}

/* -----------------------------------------------------------------------------
 * Frame buffer operations
 */

static int sh_mobile_lcdc_setcolreg(u_int regno,
                                    u_int red, u_int green, u_int blue,
                                    u_int transp, struct fb_info *info)
{
        u32 *palette = info->pseudo_palette;

        if (regno >= PALETTE_NR)
                return -EINVAL;

        /* only FB_VISUAL_TRUECOLOR supported */

        red >>= 16 - info->var.red.length;
        green >>= 16 - info->var.green.length;
        blue >>= 16 - info->var.blue.length;
        transp >>= 16 - info->var.transp.length;

        palette[regno] = (red << info->var.red.offset) |
          (green << info->var.green.offset) |
          (blue << info->var.blue.offset) |
          (transp << info->var.transp.offset);

        return 0;
}

static struct fb_fix_screeninfo sh_mobile_lcdc_fix  = {
        .id =           "SH Mobile LCDC",
        .type =         FB_TYPE_PACKED_PIXELS,
        .visual =       FB_VISUAL_TRUECOLOR,
        .accel =        FB_ACCEL_NONE,
        .xpanstep =     0,
        .ypanstep =     1,
        .ywrapstep =    0,
        .capabilities = FB_CAP_FOURCC,
};

static void sh_mobile_lcdc_fillrect(struct fb_info *info,
                                    const struct fb_fillrect *rect)
{
        sys_fillrect(info, rect);
        sh_mobile_lcdc_deferred_io_touch(info);
}

static void sh_mobile_lcdc_copyarea(struct fb_info *info,
                                    const struct fb_copyarea *area)
{
        sys_copyarea(info, area);
        sh_mobile_lcdc_deferred_io_touch(info);
}

static void sh_mobile_lcdc_imageblit(struct fb_info *info,
                                     const struct fb_image *image)
{
        sys_imageblit(info, image);
        sh_mobile_lcdc_deferred_io_touch(info);
}

static int sh_mobile_fb_pan_display(struct fb_var_screeninfo *var,
                                     struct fb_info *info)
{
        struct sh_mobile_lcdc_chan *ch = info->par;
        struct sh_mobile_lcdc_priv *priv = ch->lcdc;
        unsigned long ldrcntr;
        unsigned long new_pan_offset;
        unsigned long base_addr_y, base_addr_c;
        unsigned long c_offset;

        if (!ch->format->yuv)
                new_pan_offset = var->yoffset * ch->pitch
                               + var->xoffset * (ch->format->bpp / 8);
        else
                new_pan_offset = var->yoffset * ch->pitch + var->xoffset;

        if (new_pan_offset == ch->pan_offset)
                return 0;       /* No change, do nothing */

        ldrcntr = lcdc_read(priv, _LDRCNTR);

        /* Set the source address for the next refresh */
        base_addr_y = ch->dma_handle + new_pan_offset;
        if (ch->format->yuv) {
                /* Set y offset */
                c_offset = var->yoffset * ch->pitch
                         * (ch->format->bpp - 8) / 8;
                base_addr_c = ch->dma_handle + ch->xres * ch->yres_virtual
                            + c_offset;
                /* Set x offset */
                if (ch->format->fourcc == V4L2_PIX_FMT_NV24)
                        base_addr_c += 2 * var->xoffset;
                else
                        base_addr_c += var->xoffset;
        }

        if (ch->meram) {
                struct sh_mobile_meram_info *mdev;

                mdev = priv->meram_dev;
                mdev->ops->meram_update(mdev, ch->meram,
                                        base_addr_y, base_addr_c,
                                        &base_addr_y, &base_addr_c);
        }

        ch->base_addr_y = base_addr_y;
        ch->base_addr_c = base_addr_c;

        lcdc_write_chan_mirror(ch, LDSA1R, base_addr_y);
        if (ch->format->yuv)
                lcdc_write_chan_mirror(ch, LDSA2R, base_addr_c);

        if (lcdc_chan_is_sublcd(ch))
                lcdc_write(ch->lcdc, _LDRCNTR, ldrcntr ^ LDRCNTR_SRS);
        else
                lcdc_write(ch->lcdc, _LDRCNTR, ldrcntr ^ LDRCNTR_MRS);

        ch->pan_offset = new_pan_offset;

        sh_mobile_lcdc_deferred_io_touch(info);

        return 0;
}

static int sh_mobile_ioctl(struct fb_info *info, unsigned int cmd,
                       unsigned long arg)
{
        int retval;

        switch (cmd) {
        case FBIO_WAITFORVSYNC:
                retval = sh_mobile_wait_for_vsync(info->par);
                break;

        default:
                retval = -ENOIOCTLCMD;
                break;
        }
        return retval;
}

static void sh_mobile_fb_reconfig(struct fb_info *info)
{
        struct sh_mobile_lcdc_chan *ch = info->par;
        struct fb_var_screeninfo var;
        struct fb_videomode mode;
        struct fb_event event;
        int evnt = FB_EVENT_MODE_CHANGE_ALL;

        if (ch->use_count > 1 || (ch->use_count == 1 && !info->fbcon_par))
                /* More framebuffer users are active */
                return;

        fb_var_to_videomode(&mode, &info->var);

        if (fb_mode_is_equal(&ch->display.mode, &mode))
                return;

        /* Display has been re-plugged, framebuffer is free now, reconfigure */
        var = info->var;
        fb_videomode_to_var(&var, &ch->display.mode);
        var.width = ch->display.width;
        var.height = ch->display.height;
        var.activate = FB_ACTIVATE_NOW;

        if (fb_set_var(info, &var) < 0)
                /* Couldn't reconfigure, hopefully, can continue as before */
                return;

        /*
         * fb_set_var() calls the notifier change internally, only if
         * FBINFO_MISC_USEREVENT flag is set. Since we do not want to fake a
         * user event, we have to call the chain ourselves.
         */
        event.info = info;
        event.data = &ch->display.mode;
        fb_notifier_call_chain(evnt, &event);
}

/*
 * Locking: both .fb_release() and .fb_open() are called with info->lock held if
 * user == 1, or with console sem held, if user == 0.
 */
static int sh_mobile_release(struct fb_info *info, int user)
{
        struct sh_mobile_lcdc_chan *ch = info->par;

        mutex_lock(&ch->open_lock);
        dev_dbg(info->dev, "%s(): %d users\n", __func__, ch->use_count);

        ch->use_count--;

        /* Nothing to reconfigure, when called from fbcon */
        if (user) {
                console_lock();
                sh_mobile_fb_reconfig(info);
                console_unlock();
        }

        mutex_unlock(&ch->open_lock);

        return 0;
}

static int sh_mobile_open(struct fb_info *info, int user)
{
        struct sh_mobile_lcdc_chan *ch = info->par;

        mutex_lock(&ch->open_lock);
        ch->use_count++;

        dev_dbg(info->dev, "%s(): %d users\n", __func__, ch->use_count);
        mutex_unlock(&ch->open_lock);

        return 0;
}

static int sh_mobile_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
{
        struct sh_mobile_lcdc_chan *ch = info->par;
        struct sh_mobile_lcdc_priv *p = ch->lcdc;
        unsigned int best_dist = (unsigned int)-1;
        unsigned int best_xres = 0;
        unsigned int best_yres = 0;
        unsigned int i;

        if (var->xres > MAX_XRES || var->yres > MAX_YRES)
                return -EINVAL;

        /* If board code provides us with a list of available modes, make sure
         * we use one of them. Find the mode closest to the requested one. The
         * distance between two modes is defined as the size of the
         * non-overlapping parts of the two rectangles.
         */
        for (i = 0; i < ch->cfg->num_modes; ++i) {
                const struct fb_videomode *mode = &ch->cfg->lcd_modes[i];
                unsigned int dist;

                /* We can only round up. */
                if (var->xres > mode->xres || var->yres > mode->yres)
                        continue;

                dist = var->xres * var->yres + mode->xres * mode->yres
                     - 2 * min(var->xres, mode->xres)
                         * min(var->yres, mode->yres);

                if (dist < best_dist) {
                        best_xres = mode->xres;
                        best_yres = mode->yres;
                        best_dist = dist;
                }
        }

        /* If no available mode can be used, return an error. */
        if (ch->cfg->num_modes != 0) {
                if (best_dist == (unsigned int)-1)
                        return -EINVAL;

                var->xres = best_xres;
                var->yres = best_yres;
        }

        /* Make sure the virtual resolution is at least as big as the visible
         * resolution.
         */
        if (var->xres_virtual < var->xres)
                var->xres_virtual = var->xres;
        if (var->yres_virtual < var->yres)
                var->yres_virtual = var->yres;

        if (sh_mobile_format_is_fourcc(var)) {
                const struct sh_mobile_lcdc_format_info *format;

                format = sh_mobile_format_info(var->grayscale);
                if (format == NULL)
                        return -EINVAL;
                var->bits_per_pixel = format->bpp;

                /* Default to RGB and JPEG color-spaces for RGB and YUV formats
                 * respectively.
                 */
                if (!format->yuv)
                        var->colorspace = V4L2_COLORSPACE_SRGB;
                else if (var->colorspace != V4L2_COLORSPACE_REC709)
                        var->colorspace = V4L2_COLORSPACE_JPEG;
        } else {
                if (var->bits_per_pixel <= 16) {                /* RGB 565 */
                        var->bits_per_pixel = 16;
                        var->red.offset = 11;
                        var->red.length = 5;
                        var->green.offset = 5;
                        var->green.length = 6;
                        var->blue.offset = 0;
                        var->blue.length = 5;
                        var->transp.offset = 0;
                        var->transp.length = 0;
                } else if (var->bits_per_pixel <= 24) {         /* RGB 888 */
                        var->bits_per_pixel = 24;
                        var->red.offset = 16;
                        var->red.length = 8;
                        var->green.offset = 8;
                        var->green.length = 8;
                        var->blue.offset = 0;
                        var->blue.length = 8;
                        var->transp.offset = 0;
                        var->transp.length = 0;
                } else if (var->bits_per_pixel <= 32) {         /* RGBA 888 */
                        var->bits_per_pixel = 32;
                        var->red.offset = 16;
                        var->red.length = 8;
                        var->green.offset = 8;
                        var->green.length = 8;
                        var->blue.offset = 0;
                        var->blue.length = 8;
                        var->transp.offset = 24;
                        var->transp.length = 8;
                } else
                        return -EINVAL;

                var->red.msb_right = 0;
                var->green.msb_right = 0;
                var->blue.msb_right = 0;
                var->transp.msb_right = 0;
        }

        /* Make sure we don't exceed our allocated memory. */
        if (var->xres_virtual * var->yres_virtual * var->bits_per_pixel / 8 >
            info->fix.smem_len)
                return -EINVAL;

        /* only accept the forced_fourcc for dual channel configurations */
        if (p->forced_fourcc &&
            p->forced_fourcc != sh_mobile_format_fourcc(var))
                return -EINVAL;

        return 0;
}

static int sh_mobile_set_par(struct fb_info *info)
{
        struct sh_mobile_lcdc_chan *ch = info->par;
        int ret;

        sh_mobile_lcdc_stop(ch->lcdc);

        ch->format = sh_mobile_format_info(sh_mobile_format_fourcc(&info->var));
        ch->colorspace = info->var.colorspace;

        ch->xres = info->var.xres;
        ch->xres_virtual = info->var.xres_virtual;
        ch->yres = info->var.yres;
        ch->yres_virtual = info->var.yres_virtual;

        if (ch->format->yuv)
                ch->pitch = info->var.xres;
        else
                ch->pitch = info->var.xres * ch->format->bpp / 8;

        ret = sh_mobile_lcdc_start(ch->lcdc);
        if (ret < 0)
                dev_err(info->dev, "%s: unable to restart LCDC\n", __func__);

        info->fix.line_length = ch->pitch;

        if (sh_mobile_format_is_fourcc(&info->var)) {
                info->fix.type = FB_TYPE_FOURCC;
                info->fix.visual = FB_VISUAL_FOURCC;
        } else {
                info->fix.type = FB_TYPE_PACKED_PIXELS;
                info->fix.visual = FB_VISUAL_TRUECOLOR;
        }

        return ret;
}

/*
 * Screen blanking. Behavior is as follows:
 * FB_BLANK_UNBLANK: screen unblanked, clocks enabled
 * FB_BLANK_NORMAL: screen blanked, clocks enabled
 * FB_BLANK_VSYNC,
 * FB_BLANK_HSYNC,
 * FB_BLANK_POWEROFF: screen blanked, clocks disabled
 */
static int sh_mobile_lcdc_blank(int blank, struct fb_info *info)
{
        struct sh_mobile_lcdc_chan *ch = info->par;
        struct sh_mobile_lcdc_priv *p = ch->lcdc;

        /* blank the screen? */
        if (blank > FB_BLANK_UNBLANK && ch->blank_status == FB_BLANK_UNBLANK) {
                struct fb_fillrect rect = {
                        .width = ch->xres,
                        .height = ch->yres,
                };
                sh_mobile_lcdc_fillrect(info, &rect);
        }
        /* turn clocks on? */
        if (blank <= FB_BLANK_NORMAL && ch->blank_status > FB_BLANK_NORMAL) {
                sh_mobile_lcdc_clk_on(p);
        }
        /* turn clocks off? */
        if (blank > FB_BLANK_NORMAL && ch->blank_status <= FB_BLANK_NORMAL) {
                /* make sure the screen is updated with the black fill before
                 * switching the clocks off. one vsync is not enough since
                 * blanking may occur in the middle of a refresh. deferred io
                 * mode will reenable the clocks and update the screen in time,
                 * so it does not need this. */
                if (!info->fbdefio) {
                        sh_mobile_wait_for_vsync(ch);
                        sh_mobile_wait_for_vsync(ch);
                }
                sh_mobile_lcdc_clk_off(p);
        }

        ch->blank_status = blank;
        return 0;
}

static struct fb_ops sh_mobile_lcdc_ops = {
        .owner          = THIS_MODULE,
        .fb_setcolreg   = sh_mobile_lcdc_setcolreg,
        .fb_read        = fb_sys_read,
        .fb_write       = fb_sys_write,
        .fb_fillrect    = sh_mobile_lcdc_fillrect,
        .fb_copyarea    = sh_mobile_lcdc_copyarea,
        .fb_imageblit   = sh_mobile_lcdc_imageblit,
        .fb_blank       = sh_mobile_lcdc_blank,
        .fb_pan_display = sh_mobile_fb_pan_display,
        .fb_ioctl       = sh_mobile_ioctl,
        .fb_open        = sh_mobile_open,
        .fb_release     = sh_mobile_release,
        .fb_check_var   = sh_mobile_check_var,
        .fb_set_par     = sh_mobile_set_par,
};

static void
sh_mobile_lcdc_channel_fb_unregister(struct sh_mobile_lcdc_chan *ch)
{
        if (ch->info && ch->info->dev)
                unregister_framebuffer(ch->info);
}

static int __devinit
sh_mobile_lcdc_channel_fb_register(struct sh_mobile_lcdc_chan *ch)
{
        struct fb_info *info = ch->info;
        int ret;

        if (info->fbdefio) {
                ch->sglist = vmalloc(sizeof(struct scatterlist) *
                                     ch->fb_size >> PAGE_SHIFT);
                if (!ch->sglist) {
                        dev_err(ch->lcdc->dev, "cannot allocate sglist\n");
                        return -ENOMEM;
                }
        }

        info->bl_dev = ch->bl;

        ret = register_framebuffer(info);
        if (ret < 0)
                return ret;

        dev_info(ch->lcdc->dev, "registered %s/%s as %dx%d %dbpp.\n",
                 dev_name(ch->lcdc->dev), (ch->cfg->chan == LCDC_CHAN_MAINLCD) ?
                 "mainlcd" : "sublcd", info->var.xres, info->var.yres,
                 info->var.bits_per_pixel);

        /* deferred io mode: disable clock to save power */
        if (info->fbdefio || info->state == FBINFO_STATE_SUSPENDED)
                sh_mobile_lcdc_clk_off(ch->lcdc);

        return ret;
}

static void
sh_mobile_lcdc_channel_fb_cleanup(struct sh_mobile_lcdc_chan *ch)
{
        struct fb_info *info = ch->info;

        if (!info || !info->device)
                return;

        if (ch->sglist)
                vfree(ch->sglist);

        fb_dealloc_cmap(&info->cmap);
        framebuffer_release(info);
}

static int __devinit
sh_mobile_lcdc_channel_fb_init(struct sh_mobile_lcdc_chan *ch,
                               const struct fb_videomode *mode,
                               unsigned int num_modes)
{
        struct sh_mobile_lcdc_priv *priv = ch->lcdc;
        struct fb_var_screeninfo *var;
        struct fb_info *info;
        int ret;

        /* Allocate and initialize the frame buffer device. Create the modes
         * list and allocate the color map.
         */
        info = framebuffer_alloc(0, priv->dev);
        if (info == NULL) {
                dev_err(priv->dev, "unable to allocate fb_info\n");
                return -ENOMEM;
        }

        ch->info = info;

        info->flags = FBINFO_FLAG_DEFAULT;
        info->fbops = &sh_mobile_lcdc_ops;
        info->device = priv->dev;
        info->screen_base = ch->fb_mem;
        info->pseudo_palette = &ch->pseudo_palette;
        info->par = ch;

        fb_videomode_to_modelist(mode, num_modes, &info->modelist);

        ret = fb_alloc_cmap(&info->cmap, PALETTE_NR, 0);
        if (ret < 0) {
                dev_err(priv->dev, "unable to allocate cmap\n");
                return ret;
        }

        /* Initialize fixed screen information. Restrict pan to 2 lines steps
         * for NV12 and NV21.
         */
        info->fix = sh_mobile_lcdc_fix;
        info->fix.smem_start = ch->dma_handle;
        info->fix.smem_len = ch->fb_size;
        info->fix.line_length = ch->pitch;

        if (ch->format->yuv)
                info->fix.visual = FB_VISUAL_FOURCC;
        else
                info->fix.visual = FB_VISUAL_TRUECOLOR;

        if (ch->format->fourcc == V4L2_PIX_FMT_NV12 ||
            ch->format->fourcc == V4L2_PIX_FMT_NV21)
                info->fix.ypanstep = 2;

        /* Initialize variable screen information using the first mode as
         * default. The default Y virtual resolution is twice the panel size to
         * allow for double-buffering.
         */
        var = &info->var;
        fb_videomode_to_var(var, mode);
        var->width = ch->cfg->panel_cfg.width;
        var->height = ch->cfg->panel_cfg.height;
        var->yres_virtual = var->yres * 2;
        var->activate = FB_ACTIVATE_NOW;

        /* Use the legacy API by default for RGB formats, and the FOURCC API
         * for YUV formats.
         */
        if (!ch->format->yuv)
                var->bits_per_pixel = ch->format->bpp;
        else
                var->grayscale = ch->format->fourcc;

        ret = sh_mobile_check_var(var, info);
        if (ret)
                return ret;

        return 0;
}

/* -----------------------------------------------------------------------------
 * Backlight
 */

static int sh_mobile_lcdc_update_bl(struct backlight_device *bdev)
{
        struct sh_mobile_lcdc_chan *ch = bl_get_data(bdev);
        int brightness = bdev->props.brightness;

        if (bdev->props.power != FB_BLANK_UNBLANK ||
            bdev->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
                brightness = 0;

        return ch->cfg->bl_info.set_brightness(brightness);
}

static int sh_mobile_lcdc_get_brightness(struct backlight_device *bdev)
{
        struct sh_mobile_lcdc_chan *ch = bl_get_data(bdev);

        return ch->cfg->bl_info.get_brightness();
}

static int sh_mobile_lcdc_check_fb(struct backlight_device *bdev,
                                   struct fb_info *info)
{
        return (info->bl_dev == bdev);
}

static struct backlight_ops sh_mobile_lcdc_bl_ops = {
        .options        = BL_CORE_SUSPENDRESUME,
        .update_status  = sh_mobile_lcdc_update_bl,
        .get_brightness = sh_mobile_lcdc_get_brightness,
        .check_fb       = sh_mobile_lcdc_check_fb,
};

static struct backlight_device *sh_mobile_lcdc_bl_probe(struct device *parent,
                                               struct sh_mobile_lcdc_chan *ch)
{
        struct backlight_device *bl;

        bl = backlight_device_register(ch->cfg->bl_info.name, parent, ch,
                                       &sh_mobile_lcdc_bl_ops, NULL);
        if (IS_ERR(bl)) {
                dev_err(parent, "unable to register backlight device: %ld\n",
                        PTR_ERR(bl));
                return NULL;
        }

        bl->props.max_brightness = ch->cfg->bl_info.max_brightness;
        bl->props.brightness = bl->props.max_brightness;
        backlight_update_status(bl);

        return bl;
}

static void sh_mobile_lcdc_bl_remove(struct backlight_device *bdev)
{
        backlight_device_unregister(bdev);
}

/* -----------------------------------------------------------------------------
 * Power management
 */

static int sh_mobile_lcdc_suspend(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);

        sh_mobile_lcdc_stop(platform_get_drvdata(pdev));
        return 0;
}

static int sh_mobile_lcdc_resume(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);

        return sh_mobile_lcdc_start(platform_get_drvdata(pdev));
}

static int sh_mobile_lcdc_runtime_suspend(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct sh_mobile_lcdc_priv *priv = platform_get_drvdata(pdev);

        /* turn off LCDC hardware */
        lcdc_write(priv, _LDCNT1R, 0);

        return 0;
}

static int sh_mobile_lcdc_runtime_resume(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct sh_mobile_lcdc_priv *priv = platform_get_drvdata(pdev);

        __sh_mobile_lcdc_start(priv);

        return 0;
}

static const struct dev_pm_ops sh_mobile_lcdc_dev_pm_ops = {
        .suspend = sh_mobile_lcdc_suspend,
        .resume = sh_mobile_lcdc_resume,
        .runtime_suspend = sh_mobile_lcdc_runtime_suspend,
        .runtime_resume = sh_mobile_lcdc_runtime_resume,
};

/* -----------------------------------------------------------------------------
 * Framebuffer notifier
 */

/* locking: called with info->lock held */
static int sh_mobile_lcdc_notify(struct notifier_block *nb,
                                 unsigned long action, void *data)
{
        struct fb_event *event = data;
        struct fb_info *info = event->info;
        struct sh_mobile_lcdc_chan *ch = info->par;

        if (&ch->lcdc->notifier != nb)
                return NOTIFY_DONE;

        dev_dbg(info->dev, "%s(): action = %lu, data = %p\n",
                __func__, action, event->data);

        switch(action) {
        case FB_EVENT_SUSPEND:
                sh_mobile_lcdc_display_off(ch);
                sh_mobile_lcdc_stop(ch->lcdc);
                break;
        case FB_EVENT_RESUME:
                mutex_lock(&ch->open_lock);
                sh_mobile_fb_reconfig(info);
                mutex_unlock(&ch->open_lock);

                sh_mobile_lcdc_display_on(ch);
                sh_mobile_lcdc_start(ch->lcdc);
        }

        return NOTIFY_OK;
}

/* -----------------------------------------------------------------------------
 * Probe/remove and driver init/exit
 */

static const struct fb_videomode default_720p __devinitconst = {
        .name = "HDMI 720p",
        .xres = 1280,
        .yres = 720,

        .left_margin = 220,
        .right_margin = 110,
        .hsync_len = 40,

        .upper_margin = 20,
        .lower_margin = 5,
        .vsync_len = 5,

        .pixclock = 13468,
        .refresh = 60,
        .sync = FB_SYNC_VERT_HIGH_ACT | FB_SYNC_HOR_HIGH_ACT,
};

static int sh_mobile_lcdc_remove(struct platform_device *pdev)
{
        struct sh_mobile_lcdc_priv *priv = platform_get_drvdata(pdev);
        int i;

        fb_unregister_client(&priv->notifier);

        for (i = 0; i < ARRAY_SIZE(priv->ch); i++)
                sh_mobile_lcdc_channel_fb_unregister(&priv->ch[i]);

        sh_mobile_lcdc_stop(priv);

        for (i = 0; i < ARRAY_SIZE(priv->ch); i++) {
                struct sh_mobile_lcdc_chan *ch = &priv->ch[i];

                if (ch->tx_dev) {
                        ch->tx_dev->lcdc = NULL;
                        module_put(ch->cfg->tx_dev->dev.driver->owner);
                }

                sh_mobile_lcdc_channel_fb_cleanup(ch);

                if (ch->fb_mem)
                        dma_free_coherent(&pdev->dev, ch->fb_size,
                                          ch->fb_mem, ch->dma_handle);
        }

        for (i = 0; i < ARRAY_SIZE(priv->ch); i++) {
                if (priv->ch[i].bl)
                        sh_mobile_lcdc_bl_remove(priv->ch[i].bl);
        }

        if (priv->dot_clk) {
                pm_runtime_disable(&pdev->dev);
                clk_put(priv->dot_clk);
        }

        if (priv->base)
                iounmap(priv->base);

        if (priv->irq)
                free_irq(priv->irq, priv);
        kfree(priv);
        return 0;
}

static int __devinit sh_mobile_lcdc_check_interface(struct sh_mobile_lcdc_chan *ch)
{
        int interface_type = ch->cfg->interface_type;

        switch (interface_type) {
        case RGB8:
        case RGB9:
        case RGB12A:
        case RGB12B:
        case RGB16:
        case RGB18:
        case RGB24:
        case SYS8A:
        case SYS8B:
        case SYS8C:
        case SYS8D:
        case SYS9:
        case SYS12:
        case SYS16A:
        case SYS16B:
        case SYS16C:
        case SYS18:
        case SYS24:
                break;
        default:
                return -EINVAL;
        }

        /* SUBLCD only supports SYS interface */
        if (lcdc_chan_is_sublcd(ch)) {
                if (!(interface_type & LDMT1R_IFM))
                        return -EINVAL;

                interface_type &= ~LDMT1R_IFM;
        }

        ch->ldmt1r_value = interface_type;
        return 0;
}

static int __devinit
sh_mobile_lcdc_channel_init(struct sh_mobile_lcdc_priv *priv,
                            struct sh_mobile_lcdc_chan *ch)
{
        const struct sh_mobile_lcdc_format_info *format;
        const struct sh_mobile_lcdc_chan_cfg *cfg = ch->cfg;
        const struct fb_videomode *max_mode;
        const struct fb_videomode *mode;
        unsigned int num_modes;
        unsigned int max_size;
        unsigned int i;

        mutex_init(&ch->open_lock);
        ch->notify = sh_mobile_lcdc_display_notify;

        /* Validate the format. */
        format = sh_mobile_format_info(cfg->fourcc);
        if (format == NULL) {
                dev_err(priv->dev, "Invalid FOURCC %08x.\n", cfg->fourcc);
                return -EINVAL;
        }

        /* Iterate through the modes to validate them and find the highest
         * resolution.
         */
        max_mode = NULL;
        max_size = 0;

        for (i = 0, mode = cfg->lcd_modes; i < cfg->num_modes; i++, mode++) {
                unsigned int size = mode->yres * mode->xres;

                /* NV12/NV21 buffers must have even number of lines */
                if ((cfg->fourcc == V4L2_PIX_FMT_NV12 ||
                     cfg->fourcc == V4L2_PIX_FMT_NV21) && (mode->yres & 0x1)) {
                        dev_err(priv->dev, "yres must be multiple of 2 for "
                                "YCbCr420 mode.\n");
                        return -EINVAL;
                }

                if (size > max_size) {
                        max_mode = mode;
                        max_size = size;
                }
        }

        if (!max_size)
                max_size = MAX_XRES * MAX_YRES;
        else
                dev_dbg(priv->dev, "Found largest videomode %ux%u\n",
                        max_mode->xres, max_mode->yres);

        if (cfg->lcd_modes == NULL) {
                mode = &default_720p;
                num_modes = 1;
        } else {
                mode = cfg->lcd_modes;
                num_modes = cfg->num_modes;
        }

        /* Use the first mode as default. */
        ch->format = format;
        ch->xres = mode->xres;
        ch->xres_virtual = mode->xres;
        ch->yres = mode->yres;
        ch->yres_virtual = mode->yres * 2;

        if (!format->yuv) {
                ch->colorspace = V4L2_COLORSPACE_SRGB;
                ch->pitch = ch->xres * format->bpp / 8;
        } else {
                ch->colorspace = V4L2_COLORSPACE_REC709;
                ch->pitch = ch->xres;
        }

        ch->display.width = cfg->panel_cfg.width;
        ch->display.height = cfg->panel_cfg.height;
        ch->display.mode = *mode;

        /* Allocate frame buffer memory. */
        ch->fb_size = max_size * format->bpp / 8 * 2;
        ch->fb_mem = dma_alloc_coherent(priv->dev, ch->fb_size, &ch->dma_handle,
                                        GFP_KERNEL);
        if (ch->fb_mem == NULL) {
                dev_err(priv->dev, "unable to allocate buffer\n");
                return -ENOMEM;
        }

        /* Initialize the transmitter device if present. */
        if (cfg->tx_dev) {
                if (!cfg->tx_dev->dev.driver ||
                    !try_module_get(cfg->tx_dev->dev.driver->owner)) {
                        dev_warn(priv->dev,
                                 "unable to get transmitter device\n");
                        return -EINVAL;
                }
                ch->tx_dev = platform_get_drvdata(cfg->tx_dev);
                ch->tx_dev->lcdc = ch;
                ch->tx_dev->def_mode = *mode;
        }

        return sh_mobile_lcdc_channel_fb_init(ch, mode, num_modes);
}

static int __devinit sh_mobile_lcdc_probe(struct platform_device *pdev)
{
        struct sh_mobile_lcdc_info *pdata = pdev->dev.platform_data;
        struct sh_mobile_lcdc_priv *priv;
        struct resource *res;
        int num_channels;
        int error;
        int i;

        if (!pdata) {
                dev_err(&pdev->dev, "no platform data defined\n");
                return -EINVAL;
        }

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        i = platform_get_irq(pdev, 0);
        if (!res || i < 0) {
                dev_err(&pdev->dev, "cannot get platform resources\n");
                return -ENOENT;
        }

        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
        if (!priv) {
                dev_err(&pdev->dev, "cannot allocate device data\n");
                return -ENOMEM;
        }

        priv->dev = &pdev->dev;
        priv->meram_dev = pdata->meram_dev;
        platform_set_drvdata(pdev, priv);

        error = request_irq(i, sh_mobile_lcdc_irq, 0,
                            dev_name(&pdev->dev), priv);
        if (error) {
                dev_err(&pdev->dev, "unable to request irq\n");
                goto err1;
        }

        priv->irq = i;
        atomic_set(&priv->hw_usecnt, -1);

        for (i = 0, num_channels = 0; i < ARRAY_SIZE(pdata->ch); i++) {
                struct sh_mobile_lcdc_chan *ch = priv->ch + num_channels;

                ch->lcdc = priv;
                ch->cfg = &pdata->ch[i];

                error = sh_mobile_lcdc_check_interface(ch);
                if (error) {
                        dev_err(&pdev->dev, "unsupported interface type\n");
                        goto err1;
                }
                init_waitqueue_head(&ch->frame_end_wait);
                init_completion(&ch->vsync_completion);
                ch->pan_offset = 0;

                /* probe the backlight is there is one defined */
                if (ch->cfg->bl_info.max_brightness)
                        ch->bl = sh_mobile_lcdc_bl_probe(&pdev->dev, ch);

                switch (pdata->ch[i].chan) {
                case LCDC_CHAN_MAINLCD:
                        ch->enabled = LDCNT2R_ME;
                        ch->reg_offs = lcdc_offs_mainlcd;
                        num_channels++;
                        break;
                case LCDC_CHAN_SUBLCD:
                        ch->enabled = LDCNT2R_SE;
                        ch->reg_offs = lcdc_offs_sublcd;
                        num_channels++;
                        break;
                }
        }

        if (!num_channels) {
                dev_err(&pdev->dev, "no channels defined\n");
                error = -EINVAL;
                goto err1;
        }

        /* for dual channel LCDC (MAIN + SUB) force shared format setting */
        if (num_channels == 2)
                priv->forced_fourcc = pdata->ch[0].fourcc;

        priv->base = ioremap_nocache(res->start, resource_size(res));
        if (!priv->base)
                goto err1;

        error = sh_mobile_lcdc_setup_clocks(priv, pdata->clock_source);
        if (error) {
                dev_err(&pdev->dev, "unable to setup clocks\n");
                goto err1;
        }

        /* Enable runtime PM. */
        pm_runtime_enable(&pdev->dev);

        for (i = 0; i < num_channels; i++) {
                struct sh_mobile_lcdc_chan *ch = priv->ch + i;

                error = sh_mobile_lcdc_channel_init(priv, ch);

                if (error)
                        goto err1;
        }

        error = sh_mobile_lcdc_start(priv);
        if (error) {
                dev_err(&pdev->dev, "unable to start hardware\n");
                goto err1;
        }

        for (i = 0; i < num_channels; i++) {
                struct sh_mobile_lcdc_chan *ch = priv->ch + i;

                error = sh_mobile_lcdc_channel_fb_register(ch);
                if (error)
                        goto err1;
        }

        /* Failure ignored */
        priv->notifier.notifier_call = sh_mobile_lcdc_notify;
        fb_register_client(&priv->notifier);

        return 0;
err1:
        sh_mobile_lcdc_remove(pdev);

        return error;
}

static struct platform_driver sh_mobile_lcdc_driver = {
        .driver         = {
                .name           = "sh_mobile_lcdc_fb",
                .owner          = THIS_MODULE,
                .pm             = &sh_mobile_lcdc_dev_pm_ops,
        },
        .probe          = sh_mobile_lcdc_probe,
        .remove         = sh_mobile_lcdc_remove,
};

module_platform_driver(sh_mobile_lcdc_driver);

MODULE_DESCRIPTION("SuperH Mobile LCDC Framebuffer driver");
MODULE_AUTHOR("Magnus Damm <damm@opensource.se>");
MODULE_LICENSE("GPL v2");