/*
 *  linux/drivers/video/pxafb.c
 *
 *  Copyright (C) 1999 Eric A. Thomas.
 *  Copyright (C) 2004 Jean-Frederic Clere.
 *  Copyright (C) 2004 Ian Campbell.
 *  Copyright (C) 2004 Jeff Lackey.
 *   Based on sa1100fb.c Copyright (C) 1999 Eric A. Thomas
 *  which in turn is
 *   Based on acornfb.c Copyright (C) Russell King.
 *
 * 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.
 *
 *              Intel PXA250/210 LCD Controller Frame Buffer Driver
 *
 * Please direct your questions and comments on this driver to the following
 * email address:
 *
 *      linux-arm-kernel@lists.arm.linux.org.uk
 *
 * Add support for overlay1 and overlay2 based on pxafb_overlay.c:
 *
 *   Copyright (C) 2004, Intel Corporation
 *
 *     2003/08/27: <yu.tang@intel.com>
 *     2004/03/10: <stanley.cai@intel.com>
 *     2004/10/28: <yan.yin@intel.com>
 *
 *   Copyright (C) 2006-2008 Marvell International Ltd.
 *   All Rights Reserved
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/fb.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/cpufreq.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/completion.h>
#include <linux/mutex.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <linux/console.h>
#include <linux/of_graph.h>
#include <linux/regulator/consumer.h>
#include <video/of_display_timing.h>
#include <video/videomode.h>

#include <mach/hardware.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/div64.h>
#include <mach/bitfield.h>
#include <linux/platform_data/video-pxafb.h>

/*
 * Complain if VAR is out of range.
 */
#define DEBUG_VAR 1

#include "pxafb.h"

/* Bits which should not be set in machine configuration structures */
#define LCCR0_INVALID_CONFIG_MASK       (LCCR0_OUM | LCCR0_BM | LCCR0_QDM |\
                                         LCCR0_DIS | LCCR0_EFM | LCCR0_IUM |\
                                         LCCR0_SFM | LCCR0_LDM | LCCR0_ENB)

#define LCCR3_INVALID_CONFIG_MASK       (LCCR3_HSP | LCCR3_VSP |\
                                         LCCR3_PCD | LCCR3_BPP(0xf))

static int pxafb_activate_var(struct fb_var_screeninfo *var,
                                struct pxafb_info *);
static void set_ctrlr_state(struct pxafb_info *fbi, u_int state);
static void setup_base_frame(struct pxafb_info *fbi,
                             struct fb_var_screeninfo *var, int branch);
static int setup_frame_dma(struct pxafb_info *fbi, int dma, int pal,
                           unsigned long offset, size_t size);

static unsigned long video_mem_size = 0;

static inline unsigned long
lcd_readl(struct pxafb_info *fbi, unsigned int off)
{
        return __raw_readl(fbi->mmio_base + off);
}

static inline void
lcd_writel(struct pxafb_info *fbi, unsigned int off, unsigned long val)
{
        __raw_writel(val, fbi->mmio_base + off);
}

static inline void pxafb_schedule_work(struct pxafb_info *fbi, u_int state)
{
        unsigned long flags;

        local_irq_save(flags);
        /*
         * We need to handle two requests being made at the same time.
         * There are two important cases:
         *  1. When we are changing VT (C_REENABLE) while unblanking
         *     (C_ENABLE) We must perform the unblanking, which will
         *     do our REENABLE for us.
         *  2. When we are blanking, but immediately unblank before
         *     we have blanked.  We do the "REENABLE" thing here as
         *     well, just to be sure.
         */
        if (fbi->task_state == C_ENABLE && state == C_REENABLE)
                state = (u_int) -1;
        if (fbi->task_state == C_DISABLE && state == C_ENABLE)
                state = C_REENABLE;

        if (state != (u_int)-1) {
                fbi->task_state = state;
                schedule_work(&fbi->task);
        }
        local_irq_restore(flags);
}

static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
{
        chan &= 0xffff;
        chan >>= 16 - bf->length;
        return chan << bf->offset;
}

static int
pxafb_setpalettereg(u_int regno, u_int red, u_int green, u_int blue,
                       u_int trans, struct fb_info *info)
{
        struct pxafb_info *fbi = container_of(info, struct pxafb_info, fb);
        u_int val;

        if (regno >= fbi->palette_size)
                return 1;

        if (fbi->fb.var.grayscale) {
                fbi->palette_cpu[regno] = ((blue >> 8) & 0x00ff);
                return 0;
        }

        switch (fbi->lccr4 & LCCR4_PAL_FOR_MASK) {
        case LCCR4_PAL_FOR_0:
                val  = ((red   >>  0) & 0xf800);
                val |= ((green >>  5) & 0x07e0);
                val |= ((blue  >> 11) & 0x001f);
                fbi->palette_cpu[regno] = val;
                break;
        case LCCR4_PAL_FOR_1:
                val  = ((red   << 8) & 0x00f80000);
                val |= ((green >> 0) & 0x0000fc00);
                val |= ((blue  >> 8) & 0x000000f8);
                ((u32 *)(fbi->palette_cpu))[regno] = val;
                break;
        case LCCR4_PAL_FOR_2:
                val  = ((red   << 8) & 0x00fc0000);
                val |= ((green >> 0) & 0x0000fc00);
                val |= ((blue  >> 8) & 0x000000fc);
                ((u32 *)(fbi->palette_cpu))[regno] = val;
                break;
        case LCCR4_PAL_FOR_3:
                val  = ((red   << 8) & 0x00ff0000);
                val |= ((green >> 0) & 0x0000ff00);
                val |= ((blue  >> 8) & 0x000000ff);
                ((u32 *)(fbi->palette_cpu))[regno] = val;
                break;
        }

        return 0;
}

static int
pxafb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
                   u_int trans, struct fb_info *info)
{
        struct pxafb_info *fbi = container_of(info, struct pxafb_info, fb);
        unsigned int val;
        int ret = 1;

        /*
         * If inverse mode was selected, invert all the colours
         * rather than the register number.  The register number
         * is what you poke into the framebuffer to produce the
         * colour you requested.
         */
        if (fbi->cmap_inverse) {
                red   = 0xffff - red;
                green = 0xffff - green;
                blue  = 0xffff - blue;
        }

        /*
         * If greyscale is true, then we convert the RGB value
         * to greyscale no matter what visual we are using.
         */
        if (fbi->fb.var.grayscale)
                red = green = blue = (19595 * red + 38470 * green +
                                        7471 * blue) >> 16;

        switch (fbi->fb.fix.visual) {
        case FB_VISUAL_TRUECOLOR:
                /*
                 * 16-bit True Colour.  We encode the RGB value
                 * according to the RGB bitfield information.
                 */
                if (regno < 16) {
                        u32 *pal = fbi->fb.pseudo_palette;

                        val  = chan_to_field(red, &fbi->fb.var.red);
                        val |= chan_to_field(green, &fbi->fb.var.green);
                        val |= chan_to_field(blue, &fbi->fb.var.blue);

                        pal[regno] = val;
                        ret = 0;
                }
                break;

        case FB_VISUAL_STATIC_PSEUDOCOLOR:
        case FB_VISUAL_PSEUDOCOLOR:
                ret = pxafb_setpalettereg(regno, red, green, blue, trans, info);
                break;
        }

        return ret;
}

/* calculate pixel depth, transparency bit included, >=16bpp formats _only_ */
static inline int var_to_depth(struct fb_var_screeninfo *var)
{
        return var->red.length + var->green.length +
                var->blue.length + var->transp.length;
}

/* calculate 4-bit BPP value for LCCR3 and OVLxC1 */
static int pxafb_var_to_bpp(struct fb_var_screeninfo *var)
{
        int bpp = -EINVAL;

        switch (var->bits_per_pixel) {
        case 1:  bpp = 0; break;
        case 2:  bpp = 1; break;
        case 4:  bpp = 2; break;
        case 8:  bpp = 3; break;
        case 16: bpp = 4; break;
        case 24:
                switch (var_to_depth(var)) {
                case 18: bpp = 6; break; /* 18-bits/pixel packed */
                case 19: bpp = 8; break; /* 19-bits/pixel packed */
                case 24: bpp = 9; break;
                }
                break;
        case 32:
                switch (var_to_depth(var)) {
                case 18: bpp = 5; break; /* 18-bits/pixel unpacked */
                case 19: bpp = 7; break; /* 19-bits/pixel unpacked */
                case 25: bpp = 10; break;
                }
                break;
        }
        return bpp;
}

/*
 *  pxafb_var_to_lccr3():
 *    Convert a bits per pixel value to the correct bit pattern for LCCR3
 *
 *  NOTE: for PXA27x with overlays support, the LCCR3_PDFOR_x bits have an
 *  implication of the acutal use of transparency bit,  which we handle it
 *  here separatedly. See PXA27x Developer's Manual, Section <<7.4.6 Pixel
 *  Formats>> for the valid combination of PDFOR, PAL_FOR for various BPP.
 *
 *  Transparency for palette pixel formats is not supported at the moment.
 */
static uint32_t pxafb_var_to_lccr3(struct fb_var_screeninfo *var)
{
        int bpp = pxafb_var_to_bpp(var);
        uint32_t lccr3;

        if (bpp < 0)
                return 0;

        lccr3 = LCCR3_BPP(bpp);

        switch (var_to_depth(var)) {
        case 16: lccr3 |= var->transp.length ? LCCR3_PDFOR_3 : 0; break;
        case 18: lccr3 |= LCCR3_PDFOR_3; break;
        case 24: lccr3 |= var->transp.length ? LCCR3_PDFOR_2 : LCCR3_PDFOR_3;
                 break;
        case 19:
        case 25: lccr3 |= LCCR3_PDFOR_0; break;
        }
        return lccr3;
}

#define SET_PIXFMT(v, r, g, b, t)                               \
({                                                              \
        (v)->transp.offset = (t) ? (r) + (g) + (b) : 0;         \
        (v)->transp.length = (t) ? (t) : 0;                     \
        (v)->blue.length   = (b); (v)->blue.offset = 0;         \
        (v)->green.length  = (g); (v)->green.offset = (b);      \
        (v)->red.length    = (r); (v)->red.offset = (b) + (g);  \
})

/* set the RGBT bitfields of fb_var_screeninf according to
 * var->bits_per_pixel and given depth
 */
static void pxafb_set_pixfmt(struct fb_var_screeninfo *var, int depth)
{
        if (depth == 0)
                depth = var->bits_per_pixel;

        if (var->bits_per_pixel < 16) {
                /* indexed pixel formats */
                var->red.offset    = 0; var->red.length    = 8;
                var->green.offset  = 0; var->green.length  = 8;
                var->blue.offset   = 0; var->blue.length   = 8;
                var->transp.offset = 0; var->transp.length = 8;
        }

        switch (depth) {
        case 16: var->transp.length ?
                 SET_PIXFMT(var, 5, 5, 5, 1) :          /* RGBT555 */
                 SET_PIXFMT(var, 5, 6, 5, 0); break;    /* RGB565 */
        case 18: SET_PIXFMT(var, 6, 6, 6, 0); break;    /* RGB666 */
        case 19: SET_PIXFMT(var, 6, 6, 6, 1); break;    /* RGBT666 */
        case 24: var->transp.length ?
                 SET_PIXFMT(var, 8, 8, 7, 1) :          /* RGBT887 */
                 SET_PIXFMT(var, 8, 8, 8, 0); break;    /* RGB888 */
        case 25: SET_PIXFMT(var, 8, 8, 8, 1); break;    /* RGBT888 */
        }
}

#ifdef CONFIG_CPU_FREQ
/*
 *  pxafb_display_dma_period()
 *    Calculate the minimum period (in picoseconds) between two DMA
 *    requests for the LCD controller.  If we hit this, it means we're
 *    doing nothing but LCD DMA.
 */
static unsigned int pxafb_display_dma_period(struct fb_var_screeninfo *var)
{
        /*
         * Period = pixclock * bits_per_byte * bytes_per_transfer
         *              / memory_bits_per_pixel;
         */
        return var->pixclock * 8 * 16 / var->bits_per_pixel;
}
#endif

/*
 * Select the smallest mode that allows the desired resolution to be
 * displayed. If desired parameters can be rounded up.
 */
static struct pxafb_mode_info *pxafb_getmode(struct pxafb_mach_info *mach,
                                             struct fb_var_screeninfo *var)
{
        struct pxafb_mode_info *mode = NULL;
        struct pxafb_mode_info *modelist = mach->modes;
        unsigned int best_x = 0xffffffff, best_y = 0xffffffff;
        unsigned int i;

        for (i = 0; i < mach->num_modes; i++) {
                if (modelist[i].xres >= var->xres &&
                    modelist[i].yres >= var->yres &&
                    modelist[i].xres < best_x &&
                    modelist[i].yres < best_y &&
                    modelist[i].bpp >= var->bits_per_pixel) {
                        best_x = modelist[i].xres;
                        best_y = modelist[i].yres;
                        mode = &modelist[i];
                }
        }

        return mode;
}

static void pxafb_setmode(struct fb_var_screeninfo *var,
                          struct pxafb_mode_info *mode)
{
        var->xres               = mode->xres;
        var->yres               = mode->yres;
        var->bits_per_pixel     = mode->bpp;
        var->pixclock           = mode->pixclock;
        var->hsync_len          = mode->hsync_len;
        var->left_margin        = mode->left_margin;
        var->right_margin       = mode->right_margin;
        var->vsync_len          = mode->vsync_len;
        var->upper_margin       = mode->upper_margin;
        var->lower_margin       = mode->lower_margin;
        var->sync               = mode->sync;
        var->grayscale          = mode->cmap_greyscale;
        var->transp.length      = mode->transparency;

        /* set the initial RGBA bitfields */
        pxafb_set_pixfmt(var, mode->depth);
}

static int pxafb_adjust_timing(struct pxafb_info *fbi,
                               struct fb_var_screeninfo *var)
{
        int line_length;

        var->xres = max_t(int, var->xres, MIN_XRES);
        var->yres = max_t(int, var->yres, MIN_YRES);

        if (!(fbi->lccr0 & LCCR0_LCDT)) {
                clamp_val(var->hsync_len, 1, 64);
                clamp_val(var->vsync_len, 1, 64);
                clamp_val(var->left_margin,  1, 255);
                clamp_val(var->right_margin, 1, 255);
                clamp_val(var->upper_margin, 1, 255);
                clamp_val(var->lower_margin, 1, 255);
        }

        /* make sure each line is aligned on word boundary */
        line_length = var->xres * var->bits_per_pixel / 8;
        line_length = ALIGN(line_length, 4);
        var->xres = line_length * 8 / var->bits_per_pixel;

        /* we don't support xpan, force xres_virtual to be equal to xres */
        var->xres_virtual = var->xres;

        if (var->accel_flags & FB_ACCELF_TEXT)
                var->yres_virtual = fbi->fb.fix.smem_len / line_length;
        else
                var->yres_virtual = max(var->yres_virtual, var->yres);

        /* check for limits */
        if (var->xres > MAX_XRES || var->yres > MAX_YRES)
                return -EINVAL;

        if (var->yres > var->yres_virtual)
                return -EINVAL;

        return 0;
}

/*
 *  pxafb_check_var():
 *    Get the video params out of 'var'. If a value doesn't fit, round it up,
 *    if it's too big, return -EINVAL.
 *
 *    Round up in the following order: bits_per_pixel, xres,
 *    yres, xres_virtual, yres_virtual, xoffset, yoffset, grayscale,
 *    bitfields, horizontal timing, vertical timing.
 */
static int pxafb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
{
        struct pxafb_info *fbi = container_of(info, struct pxafb_info, fb);
        struct pxafb_mach_info *inf = fbi->inf;
        int err;

        if (inf->fixed_modes) {
                struct pxafb_mode_info *mode;

                mode = pxafb_getmode(inf, var);
                if (!mode)
                        return -EINVAL;
                pxafb_setmode(var, mode);
        }

        /* do a test conversion to BPP fields to check the color formats */
        err = pxafb_var_to_bpp(var);
        if (err < 0)
                return err;

        pxafb_set_pixfmt(var, var_to_depth(var));

        err = pxafb_adjust_timing(fbi, var);
        if (err)
                return err;

#ifdef CONFIG_CPU_FREQ
        pr_debug("pxafb: dma period = %d ps\n",
                 pxafb_display_dma_period(var));
#endif

        return 0;
}

/*
 * pxafb_set_par():
 *      Set the user defined part of the display for the specified console
 */
static int pxafb_set_par(struct fb_info *info)
{
        struct pxafb_info *fbi = container_of(info, struct pxafb_info, fb);
        struct fb_var_screeninfo *var = &info->var;

        if (var->bits_per_pixel >= 16)
                fbi->fb.fix.visual = FB_VISUAL_TRUECOLOR;
        else if (!fbi->cmap_static)
                fbi->fb.fix.visual = FB_VISUAL_PSEUDOCOLOR;
        else {
                /*
                 * Some people have weird ideas about wanting static
                 * pseudocolor maps.  I suspect their user space
                 * applications are broken.
                 */
                fbi->fb.fix.visual = FB_VISUAL_STATIC_PSEUDOCOLOR;
        }

        fbi->fb.fix.line_length = var->xres_virtual *
                                  var->bits_per_pixel / 8;
        if (var->bits_per_pixel >= 16)
                fbi->palette_size = 0;
        else
                fbi->palette_size = var->bits_per_pixel == 1 ?
                                        4 : 1 << var->bits_per_pixel;

        fbi->palette_cpu = (u16 *)&fbi->dma_buff->palette[0];

        if (fbi->fb.var.bits_per_pixel >= 16)
                fb_dealloc_cmap(&fbi->fb.cmap);
        else
                fb_alloc_cmap(&fbi->fb.cmap, 1<<fbi->fb.var.bits_per_pixel, 0);

        pxafb_activate_var(var, fbi);

        return 0;
}

static int pxafb_pan_display(struct fb_var_screeninfo *var,
                             struct fb_info *info)
{
        struct pxafb_info *fbi = container_of(info, struct pxafb_info, fb);
        struct fb_var_screeninfo newvar;
        int dma = DMA_MAX + DMA_BASE;

        if (fbi->state != C_ENABLE)
                return 0;

        /* Only take .xoffset, .yoffset and .vmode & FB_VMODE_YWRAP from what
         * was passed in and copy the rest from the old screeninfo.
         */
        memcpy(&newvar, &fbi->fb.var, sizeof(newvar));
        newvar.xoffset = var->xoffset;
        newvar.yoffset = var->yoffset;
        newvar.vmode &= ~FB_VMODE_YWRAP;
        newvar.vmode |= var->vmode & FB_VMODE_YWRAP;

        setup_base_frame(fbi, &newvar, 1);

        if (fbi->lccr0 & LCCR0_SDS)
                lcd_writel(fbi, FBR1, fbi->fdadr[dma + 1] | 0x1);

        lcd_writel(fbi, FBR0, fbi->fdadr[dma] | 0x1);
        return 0;
}

/*
 * pxafb_blank():
 *      Blank the display by setting all palette values to zero.  Note, the
 *      16 bpp mode does not really use the palette, so this will not
 *      blank the display in all modes.
 */
static int pxafb_blank(int blank, struct fb_info *info)
{
        struct pxafb_info *fbi = container_of(info, struct pxafb_info, fb);
        int i;

        switch (blank) {
        case FB_BLANK_POWERDOWN:
        case FB_BLANK_VSYNC_SUSPEND:
        case FB_BLANK_HSYNC_SUSPEND:
        case FB_BLANK_NORMAL:
                if (fbi->fb.fix.visual == FB_VISUAL_PSEUDOCOLOR ||
                    fbi->fb.fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
                        for (i = 0; i < fbi->palette_size; i++)
                                pxafb_setpalettereg(i, 0, 0, 0, 0, info);

                pxafb_schedule_work(fbi, C_DISABLE);
                /* TODO if (pxafb_blank_helper) pxafb_blank_helper(blank); */
                break;

        case FB_BLANK_UNBLANK:
                /* TODO if (pxafb_blank_helper) pxafb_blank_helper(blank); */
                if (fbi->fb.fix.visual == FB_VISUAL_PSEUDOCOLOR ||
                    fbi->fb.fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
                        fb_set_cmap(&fbi->fb.cmap, info);
                pxafb_schedule_work(fbi, C_ENABLE);
        }
        return 0;
}

static struct fb_ops pxafb_ops = {
        .owner          = THIS_MODULE,
        .fb_check_var   = pxafb_check_var,
        .fb_set_par     = pxafb_set_par,
        .fb_pan_display = pxafb_pan_display,
        .fb_setcolreg   = pxafb_setcolreg,
        .fb_fillrect    = cfb_fillrect,
        .fb_copyarea    = cfb_copyarea,
        .fb_imageblit   = cfb_imageblit,
        .fb_blank       = pxafb_blank,
};

#ifdef CONFIG_FB_PXA_OVERLAY
static void overlay1fb_setup(struct pxafb_layer *ofb)
{
        int size = ofb->fb.fix.line_length * ofb->fb.var.yres_virtual;
        unsigned long start = ofb->video_mem_phys;
        setup_frame_dma(ofb->fbi, DMA_OV1, PAL_NONE, start, size);
}

/* Depending on the enable status of overlay1/2, the DMA should be
 * updated from FDADRx (when disabled) or FBRx (when enabled).
 */
static void overlay1fb_enable(struct pxafb_layer *ofb)
{
        int enabled = lcd_readl(ofb->fbi, OVL1C1) & OVLxC1_OEN;
        uint32_t fdadr1 = ofb->fbi->fdadr[DMA_OV1] | (enabled ? 0x1 : 0);

        lcd_writel(ofb->fbi, enabled ? FBR1 : FDADR1, fdadr1);
        lcd_writel(ofb->fbi, OVL1C2, ofb->control[1]);
        lcd_writel(ofb->fbi, OVL1C1, ofb->control[0] | OVLxC1_OEN);
}

static void overlay1fb_disable(struct pxafb_layer *ofb)
{
        uint32_t lccr5;

        if (!(lcd_readl(ofb->fbi, OVL1C1) & OVLxC1_OEN))
                return;

        lccr5 = lcd_readl(ofb->fbi, LCCR5);

        lcd_writel(ofb->fbi, OVL1C1, ofb->control[0] & ~OVLxC1_OEN);

        lcd_writel(ofb->fbi, LCSR1, LCSR1_BS(1));
        lcd_writel(ofb->fbi, LCCR5, lccr5 & ~LCSR1_BS(1));
        lcd_writel(ofb->fbi, FBR1, ofb->fbi->fdadr[DMA_OV1] | 0x3);

        if (wait_for_completion_timeout(&ofb->branch_done, 1 * HZ) == 0)
                pr_warn("%s: timeout disabling overlay1\n", __func__);

        lcd_writel(ofb->fbi, LCCR5, lccr5);
}

static void overlay2fb_setup(struct pxafb_layer *ofb)
{
        int size, div = 1, pfor = NONSTD_TO_PFOR(ofb->fb.var.nonstd);
        unsigned long start[3] = { ofb->video_mem_phys, 0, 0 };

        if (pfor == OVERLAY_FORMAT_RGB || pfor == OVERLAY_FORMAT_YUV444_PACKED) {
                size = ofb->fb.fix.line_length * ofb->fb.var.yres_virtual;
                setup_frame_dma(ofb->fbi, DMA_OV2_Y, -1, start[0], size);
        } else {
                size = ofb->fb.var.xres_virtual * ofb->fb.var.yres_virtual;
                switch (pfor) {
                case OVERLAY_FORMAT_YUV444_PLANAR: div = 1; break;
                case OVERLAY_FORMAT_YUV422_PLANAR: div = 2; break;
                case OVERLAY_FORMAT_YUV420_PLANAR: div = 4; break;
                }
                start[1] = start[0] + size;
                start[2] = start[1] + size / div;
                setup_frame_dma(ofb->fbi, DMA_OV2_Y,  -1, start[0], size);
                setup_frame_dma(ofb->fbi, DMA_OV2_Cb, -1, start[1], size / div);
                setup_frame_dma(ofb->fbi, DMA_OV2_Cr, -1, start[2], size / div);
        }
}

static void overlay2fb_enable(struct pxafb_layer *ofb)
{
        int pfor = NONSTD_TO_PFOR(ofb->fb.var.nonstd);
        int enabled = lcd_readl(ofb->fbi, OVL2C1) & OVLxC1_OEN;
        uint32_t fdadr2 = ofb->fbi->fdadr[DMA_OV2_Y]  | (enabled ? 0x1 : 0);
        uint32_t fdadr3 = ofb->fbi->fdadr[DMA_OV2_Cb] | (enabled ? 0x1 : 0);
        uint32_t fdadr4 = ofb->fbi->fdadr[DMA_OV2_Cr] | (enabled ? 0x1 : 0);

        if (pfor == OVERLAY_FORMAT_RGB || pfor == OVERLAY_FORMAT_YUV444_PACKED)
                lcd_writel(ofb->fbi, enabled ? FBR2 : FDADR2, fdadr2);
        else {
                lcd_writel(ofb->fbi, enabled ? FBR2 : FDADR2, fdadr2);
                lcd_writel(ofb->fbi, enabled ? FBR3 : FDADR3, fdadr3);
                lcd_writel(ofb->fbi, enabled ? FBR4 : FDADR4, fdadr4);
        }
        lcd_writel(ofb->fbi, OVL2C2, ofb->control[1]);
        lcd_writel(ofb->fbi, OVL2C1, ofb->control[0] | OVLxC1_OEN);
}

static void overlay2fb_disable(struct pxafb_layer *ofb)
{
        uint32_t lccr5;

        if (!(lcd_readl(ofb->fbi, OVL2C1) & OVLxC1_OEN))
                return;

        lccr5 = lcd_readl(ofb->fbi, LCCR5);

        lcd_writel(ofb->fbi, OVL2C1, ofb->control[0] & ~OVLxC1_OEN);

        lcd_writel(ofb->fbi, LCSR1, LCSR1_BS(2));
        lcd_writel(ofb->fbi, LCCR5, lccr5 & ~LCSR1_BS(2));
        lcd_writel(ofb->fbi, FBR2, ofb->fbi->fdadr[DMA_OV2_Y]  | 0x3);
        lcd_writel(ofb->fbi, FBR3, ofb->fbi->fdadr[DMA_OV2_Cb] | 0x3);
        lcd_writel(ofb->fbi, FBR4, ofb->fbi->fdadr[DMA_OV2_Cr] | 0x3);

        if (wait_for_completion_timeout(&ofb->branch_done, 1 * HZ) == 0)
                pr_warn("%s: timeout disabling overlay2\n", __func__);
}

static struct pxafb_layer_ops ofb_ops[] = {
        [0] = {
                .enable         = overlay1fb_enable,
                .disable        = overlay1fb_disable,
                .setup          = overlay1fb_setup,
        },
        [1] = {
                .enable         = overlay2fb_enable,
                .disable        = overlay2fb_disable,
                .setup          = overlay2fb_setup,
        },
};

static int overlayfb_open(struct fb_info *info, int user)
{
        struct pxafb_layer *ofb = container_of(info, struct pxafb_layer, fb);

        /* no support for framebuffer console on overlay */
        if (user == 0)
                return -ENODEV;

        if (ofb->usage++ == 0) {
                /* unblank the base framebuffer */
                console_lock();
                fb_blank(&ofb->fbi->fb, FB_BLANK_UNBLANK);
                console_unlock();
        }

        return 0;
}

static int overlayfb_release(struct fb_info *info, int user)
{
        struct pxafb_layer *ofb = container_of(info, struct pxafb_layer, fb);

        if (ofb->usage == 1) {
                ofb->ops->disable(ofb);
                ofb->fb.var.height      = -1;
                ofb->fb.var.width       = -1;
                ofb->fb.var.xres = ofb->fb.var.xres_virtual = 0;
                ofb->fb.var.yres = ofb->fb.var.yres_virtual = 0;

                ofb->usage--;
        }
        return 0;
}

static int overlayfb_check_var(struct fb_var_screeninfo *var,
                               struct fb_info *info)
{
        struct pxafb_layer *ofb = container_of(info, struct pxafb_layer, fb);
        struct fb_var_screeninfo *base_var = &ofb->fbi->fb.var;
        int xpos, ypos, pfor, bpp;

        xpos = NONSTD_TO_XPOS(var->nonstd);
        ypos = NONSTD_TO_YPOS(var->nonstd);
        pfor = NONSTD_TO_PFOR(var->nonstd);

        bpp = pxafb_var_to_bpp(var);
        if (bpp < 0)
                return -EINVAL;

        /* no support for YUV format on overlay1 */
        if (ofb->id == OVERLAY1 && pfor != 0)
                return -EINVAL;

        /* for YUV packed formats, bpp = 'minimum bpp of YUV components' */
        switch (pfor) {
        case OVERLAY_FORMAT_RGB:
                bpp = pxafb_var_to_bpp(var);
                if (bpp < 0)
                        return -EINVAL;

                pxafb_set_pixfmt(var, var_to_depth(var));
                break;
        case OVERLAY_FORMAT_YUV444_PACKED: bpp = 24; break;
        case OVERLAY_FORMAT_YUV444_PLANAR: bpp = 8; break;
        case OVERLAY_FORMAT_YUV422_PLANAR: bpp = 4; break;
        case OVERLAY_FORMAT_YUV420_PLANAR: bpp = 2; break;
        default:
                return -EINVAL;
        }

        /* each line must start at a 32-bit word boundary */
        if ((xpos * bpp) % 32)
                return -EINVAL;

        /* xres must align on 32-bit word boundary */
        var->xres = roundup(var->xres * bpp, 32) / bpp;

        if ((xpos + var->xres > base_var->xres) ||
            (ypos + var->yres > base_var->yres))
                return -EINVAL;

        var->xres_virtual = var->xres;
        var->yres_virtual = max(var->yres, var->yres_virtual);
        return 0;
}

static int overlayfb_check_video_memory(struct pxafb_layer *ofb)
{
        struct fb_var_screeninfo *var = &ofb->fb.var;
        int pfor = NONSTD_TO_PFOR(var->nonstd);
        int size, bpp = 0;

        switch (pfor) {
        case OVERLAY_FORMAT_RGB: bpp = var->bits_per_pixel; break;
        case OVERLAY_FORMAT_YUV444_PACKED: bpp = 24; break;
        case OVERLAY_FORMAT_YUV444_PLANAR: bpp = 24; break;
        case OVERLAY_FORMAT_YUV422_PLANAR: bpp = 16; break;
        case OVERLAY_FORMAT_YUV420_PLANAR: bpp = 12; break;
        }

        ofb->fb.fix.line_length = var->xres_virtual * bpp / 8;

        size = PAGE_ALIGN(ofb->fb.fix.line_length * var->yres_virtual);

        if (ofb->video_mem) {
                if (ofb->video_mem_size >= size)
                        return 0;
        }
        return -EINVAL;
}

static int overlayfb_set_par(struct fb_info *info)
{
        struct pxafb_layer *ofb = container_of(info, struct pxafb_layer, fb);
        struct fb_var_screeninfo *var = &info->var;
        int xpos, ypos, pfor, bpp, ret;

        ret = overlayfb_check_video_memory(ofb);
        if (ret)
                return ret;

        bpp  = pxafb_var_to_bpp(var);
        xpos = NONSTD_TO_XPOS(var->nonstd);
        ypos = NONSTD_TO_YPOS(var->nonstd);
        pfor = NONSTD_TO_PFOR(var->nonstd);

        ofb->control[0] = OVLxC1_PPL(var->xres) | OVLxC1_LPO(var->yres) |
                          OVLxC1_BPP(bpp);
        ofb->control[1] = OVLxC2_XPOS(xpos) | OVLxC2_YPOS(ypos);

        if (ofb->id == OVERLAY2)
                ofb->control[1] |= OVL2C2_PFOR(pfor);

        ofb->ops->setup(ofb);
        ofb->ops->enable(ofb);
        return 0;
}

static struct fb_ops overlay_fb_ops = {
        .owner                  = THIS_MODULE,
        .fb_open                = overlayfb_open,
        .fb_release             = overlayfb_release,
        .fb_check_var           = overlayfb_check_var,
        .fb_set_par             = overlayfb_set_par,
};

static void init_pxafb_overlay(struct pxafb_info *fbi, struct pxafb_layer *ofb,
                               int id)
{
        sprintf(ofb->fb.fix.id, "overlay%d", id + 1);

        ofb->fb.fix.type                = FB_TYPE_PACKED_PIXELS;
        ofb->fb.fix.xpanstep            = 0;
        ofb->fb.fix.ypanstep            = 1;

        ofb->fb.var.activate            = FB_ACTIVATE_NOW;
        ofb->fb.var.height              = -1;
        ofb->fb.var.width               = -1;
        ofb->fb.var.vmode               = FB_VMODE_NONINTERLACED;

        ofb->fb.fbops                   = &overlay_fb_ops;
        ofb->fb.flags                   = FBINFO_FLAG_DEFAULT;
        ofb->fb.node                    = -1;
        ofb->fb.pseudo_palette          = NULL;

        ofb->id = id;
        ofb->ops = &ofb_ops[id];
        ofb->usage = 0;
        ofb->fbi = fbi;
        init_completion(&ofb->branch_done);
}

static inline int pxafb_overlay_supported(void)
{
        if (cpu_is_pxa27x() || cpu_is_pxa3xx())
                return 1;

        return 0;
}

static int pxafb_overlay_map_video_memory(struct pxafb_info *pxafb,
                                          struct pxafb_layer *ofb)
{
        /* We assume that user will use at most video_mem_size for overlay fb,
         * anyway, it's useless to use 16bpp main plane and 24bpp overlay
         */
        ofb->video_mem = alloc_pages_exact(PAGE_ALIGN(pxafb->video_mem_size),
                GFP_KERNEL | __GFP_ZERO);
        if (ofb->video_mem == NULL)
                return -ENOMEM;

        ofb->video_mem_phys = virt_to_phys(ofb->video_mem);
        ofb->video_mem_size = PAGE_ALIGN(pxafb->video_mem_size);

        mutex_lock(&ofb->fb.mm_lock);
        ofb->fb.fix.smem_start  = ofb->video_mem_phys;
        ofb->fb.fix.smem_len    = pxafb->video_mem_size;
        mutex_unlock(&ofb->fb.mm_lock);

        ofb->fb.screen_base     = ofb->video_mem;

        return 0;
}

static void pxafb_overlay_init(struct pxafb_info *fbi)
{
        int i, ret;

        if (!pxafb_overlay_supported())
                return;

        for (i = 0; i < 2; i++) {
                struct pxafb_layer *ofb = &fbi->overlay[i];
                init_pxafb_overlay(fbi, ofb, i);
                ret = register_framebuffer(&ofb->fb);
                if (ret) {
                        dev_err(fbi->dev, "failed to register overlay %d\n", i);
                        continue;
                }
                ret = pxafb_overlay_map_video_memory(fbi, ofb);
                if (ret) {
                        dev_err(fbi->dev,
                                "failed to map video memory for overlay %d\n",
                                i);
                        unregister_framebuffer(&ofb->fb);
                        continue;
                }
                ofb->registered = 1;
        }

        /* mask all IU/BS/EOF/SOF interrupts */
        lcd_writel(fbi, LCCR5, ~0);

        pr_info("PXA Overlay driver loaded successfully!\n");
}

static void pxafb_overlay_exit(struct pxafb_info *fbi)
{
        int i;

        if (!pxafb_overlay_supported())
                return;

        for (i = 0; i < 2; i++) {
                struct pxafb_layer *ofb = &fbi->overlay[i];
                if (ofb->registered) {
                        if (ofb->video_mem)
                                free_pages_exact(ofb->video_mem,
                                        ofb->video_mem_size);
                        unregister_framebuffer(&ofb->fb);
                }
        }
}
#else
static inline void pxafb_overlay_init(struct pxafb_info *fbi) {}
static inline void pxafb_overlay_exit(struct pxafb_info *fbi) {}
#endif /* CONFIG_FB_PXA_OVERLAY */

/*
 * Calculate the PCD value from the clock rate (in picoseconds).
 * We take account of the PPCR clock setting.
 * From PXA Developer's Manual:
 *
 *   PixelClock =      LCLK
 *                -------------
 *                2 ( PCD + 1 )
 *
 *   PCD =      LCLK
 *         ------------- - 1
 *         2(PixelClock)
 *

 * Where:
 *   LCLK = LCD/Memory Clock
 *   PCD = LCCR3[7:0]
 *
 * PixelClock here is in Hz while the pixclock argument given is the
 * period in picoseconds. Hence PixelClock = 1 / ( pixclock * 10^-12 )
 *
 * The function get_lclk_frequency_10khz returns LCLK in units of
 * 10khz. Calling the result of this function lclk gives us the
 * following
 *
 *    PCD = (lclk * 10^4 ) * ( pixclock * 10^-12 )
 *          -------------------------------------- - 1
 *                          2
 *
 * Factoring the 10^4 and 10^-12 out gives 10^-8 == 1 / 100000000 as used below.
 */
static inline unsigned int get_pcd(struct pxafb_info *fbi,
                                   unsigned int pixclock)
{
        unsigned long long pcd;

        /* FIXME: Need to take into account Double Pixel Clock mode
         * (DPC) bit? or perhaps set it based on the various clock
         * speeds */
        pcd = (unsigned long long)(clk_get_rate(fbi->clk) / 10000);
        pcd *= pixclock;
        do_div(pcd, 100000000 * 2);
        /* no need for this, since we should subtract 1 anyway. they cancel */
        /* pcd += 1; */ /* make up for integer math truncations */
        return (unsigned int)pcd;
}

/*
 * Some touchscreens need hsync information from the video driver to
 * function correctly. We export it here.  Note that 'hsync_time' and
 * the value returned from pxafb_get_hsync_time() is the *reciprocal*
 * of the hsync period in seconds.
 */
static inline void set_hsync_time(struct pxafb_info *fbi, unsigned int pcd)
{
        unsigned long htime;

        if ((pcd == 0) || (fbi->fb.var.hsync_len == 0)) {
                fbi->hsync_time = 0;
                return;
        }

        htime = clk_get_rate(fbi->clk) / (pcd * fbi->fb.var.hsync_len);

        fbi->hsync_time = htime;
}

unsigned long pxafb_get_hsync_time(struct device *dev)
{
        struct pxafb_info *fbi = dev_get_drvdata(dev);

        /* If display is blanked/suspended, hsync isn't active */
        if (!fbi || (fbi->state != C_ENABLE))
                return 0;

        return fbi->hsync_time;
}
EXPORT_SYMBOL(pxafb_get_hsync_time);

static int setup_frame_dma(struct pxafb_info *fbi, int dma, int pal,
                           unsigned long start, size_t size)
{
        struct pxafb_dma_descriptor *dma_desc, *pal_desc;
        unsigned int dma_desc_off, pal_desc_off;

        if (dma < 0 || dma >= DMA_MAX * 2)
                return -EINVAL;

        dma_desc = &fbi->dma_buff->dma_desc[dma];
        dma_desc_off = offsetof(struct pxafb_dma_buff, dma_desc[dma]);

        dma_desc->fsadr = start;
        dma_desc->fidr  = 0;
        dma_desc->ldcmd = size;

        if (pal < 0 || pal >= PAL_MAX * 2) {
                dma_desc->fdadr = fbi->dma_buff_phys + dma_desc_off;
                fbi->fdadr[dma] = fbi->dma_buff_phys + dma_desc_off;
        } else {
                pal_desc = &fbi->dma_buff->pal_desc[pal];
                pal_desc_off = offsetof(struct pxafb_dma_buff, pal_desc[pal]);

                pal_desc->fsadr = fbi->dma_buff_phys + pal * PALETTE_SIZE;
                pal_desc->fidr  = 0;

                if ((fbi->lccr4 & LCCR4_PAL_FOR_MASK) == LCCR4_PAL_FOR_0)
                        pal_desc->ldcmd = fbi->palette_size * sizeof(u16);
                else
                        pal_desc->ldcmd = fbi->palette_size * sizeof(u32);

                pal_desc->ldcmd |= LDCMD_PAL;

                /* flip back and forth between palette and frame buffer */
                pal_desc->fdadr = fbi->dma_buff_phys + dma_desc_off;
                dma_desc->fdadr = fbi->dma_buff_phys + pal_desc_off;
                fbi->fdadr[dma] = fbi->dma_buff_phys + dma_desc_off;
        }

        return 0;
}

static void setup_base_frame(struct pxafb_info *fbi,
                             struct fb_var_screeninfo *var,
                             int branch)
{
        struct fb_fix_screeninfo *fix = &fbi->fb.fix;
        int nbytes, dma, pal, bpp = var->bits_per_pixel;
        unsigned long offset;

        dma = DMA_BASE + (branch ? DMA_MAX : 0);
        pal = (bpp >= 16) ? PAL_NONE : PAL_BASE + (branch ? PAL_MAX : 0);

        nbytes = fix->line_length * var->yres;
        offset = fix->line_length * var->yoffset + fbi->video_mem_phys;

        if (fbi->lccr0 & LCCR0_SDS) {
                nbytes = nbytes / 2;
                setup_frame_dma(fbi, dma + 1, PAL_NONE, offset + nbytes, nbytes);
        }

        setup_frame_dma(fbi, dma, pal, offset, nbytes);
}

#ifdef CONFIG_FB_PXA_SMARTPANEL
static int setup_smart_dma(struct pxafb_info *fbi)
{
        struct pxafb_dma_descriptor *dma_desc;
        unsigned long dma_desc_off, cmd_buff_off;

        dma_desc = &fbi->dma_buff->dma_desc[DMA_CMD];
        dma_desc_off = offsetof(struct pxafb_dma_buff, dma_desc[DMA_CMD]);
        cmd_buff_off = offsetof(struct pxafb_dma_buff, cmd_buff);

        dma_desc->fdadr = fbi->dma_buff_phys + dma_desc_off;
        dma_desc->fsadr = fbi->dma_buff_phys + cmd_buff_off;
        dma_desc->fidr  = 0;
        dma_desc->ldcmd = fbi->n_smart_cmds * sizeof(uint16_t);

        fbi->fdadr[DMA_CMD] = dma_desc->fdadr;
        return 0;
}

int pxafb_smart_flush(struct fb_info *info)
{
        struct pxafb_info *fbi = container_of(info, struct pxafb_info, fb);
        uint32_t prsr;
        int ret = 0;

        /* disable controller until all registers are set up */
        lcd_writel(fbi, LCCR0, fbi->reg_lccr0 & ~LCCR0_ENB);

        /* 1. make it an even number of commands to align on 32-bit boundary
         * 2. add the interrupt command to the end of the chain so we can
         *    keep track of the end of the transfer
         */

        while (fbi->n_smart_cmds & 1)
                fbi->smart_cmds[fbi->n_smart_cmds++] = SMART_CMD_NOOP;

        fbi->smart_cmds[fbi->n_smart_cmds++] = SMART_CMD_INTERRUPT;
        fbi->smart_cmds[fbi->n_smart_cmds++] = SMART_CMD_WAIT_FOR_VSYNC;
        setup_smart_dma(fbi);

        /* continue to execute next command */
        prsr = lcd_readl(fbi, PRSR) | PRSR_ST_OK | PRSR_CON_NT;
        lcd_writel(fbi, PRSR, prsr);

        /* stop the processor in case it executed "wait for sync" cmd */
        lcd_writel(fbi, CMDCR, 0x0001);

        /* don't send interrupts for fifo underruns on channel 6 */
        lcd_writel(fbi, LCCR5, LCCR5_IUM(6));

        lcd_writel(fbi, LCCR1, fbi->reg_lccr1);
        lcd_writel(fbi, LCCR2, fbi->reg_lccr2);
        lcd_writel(fbi, LCCR3, fbi->reg_lccr3);
        lcd_writel(fbi, LCCR4, fbi->reg_lccr4);
        lcd_writel(fbi, FDADR0, fbi->fdadr[0]);
        lcd_writel(fbi, FDADR6, fbi->fdadr[6]);

        /* begin sending */
        lcd_writel(fbi, LCCR0, fbi->reg_lccr0 | LCCR0_ENB);

        if (wait_for_completion_timeout(&fbi->command_done, HZ/2) == 0) {
                pr_warn("%s: timeout waiting for command done\n", __func__);
                ret = -ETIMEDOUT;
        }

        /* quick disable */
        prsr = lcd_readl(fbi, PRSR) & ~(PRSR_ST_OK | PRSR_CON_NT);
        lcd_writel(fbi, PRSR, prsr);
        lcd_writel(fbi, LCCR0, fbi->reg_lccr0 & ~LCCR0_ENB);
        lcd_writel(fbi, FDADR6, 0);
        fbi->n_smart_cmds = 0;
        return ret;
}

int pxafb_smart_queue(struct fb_info *info, uint16_t *cmds, int n_cmds)
{
        int i;
        struct pxafb_info *fbi = container_of(info, struct pxafb_info, fb);

        for (i = 0; i < n_cmds; i++, cmds++) {
                /* if it is a software delay, flush and delay */
                if ((*cmds & 0xff00) == SMART_CMD_DELAY) {
                        pxafb_smart_flush(info);
                        mdelay(*cmds & 0xff);
                        continue;
                }

                /* leave 2 commands for INTERRUPT and WAIT_FOR_SYNC */
                if (fbi->n_smart_cmds == CMD_BUFF_SIZE - 8)
                        pxafb_smart_flush(info);

                fbi->smart_cmds[fbi->n_smart_cmds++] = *cmds;
        }

        return 0;
}

static unsigned int __smart_timing(unsigned time_ns, unsigned long lcd_clk)
{
        unsigned int t = (time_ns * (lcd_clk / 1000000) / 1000);
        return (t == 0) ? 1 : t;
}

static void setup_smart_timing(struct pxafb_info *fbi,
                                struct fb_var_screeninfo *var)
{
        struct pxafb_mach_info *inf = fbi->inf;
        struct pxafb_mode_info *mode = &inf->modes[0];
        unsigned long lclk = clk_get_rate(fbi->clk);
        unsigned t1, t2, t3, t4;

        t1 = max(mode->a0csrd_set_hld, mode->a0cswr_set_hld);
        t2 = max(mode->rd_pulse_width, mode->wr_pulse_width);
        t3 = mode->op_hold_time;
        t4 = mode->cmd_inh_time;

        fbi->reg_lccr1 =
                LCCR1_DisWdth(var->xres) |
                LCCR1_BegLnDel(__smart_timing(t1, lclk)) |
                LCCR1_EndLnDel(__smart_timing(t2, lclk)) |
                LCCR1_HorSnchWdth(__smart_timing(t3, lclk));

        fbi->reg_lccr2 = LCCR2_DisHght(var->yres);
        fbi->reg_lccr3 = fbi->lccr3 | LCCR3_PixClkDiv(__smart_timing(t4, lclk));
        fbi->reg_lccr3 |= (var->sync & FB_SYNC_HOR_HIGH_ACT) ? LCCR3_HSP : 0;
        fbi->reg_lccr3 |= (var->sync & FB_SYNC_VERT_HIGH_ACT) ? LCCR3_VSP : 0;

        /* FIXME: make this configurable */
        fbi->reg_cmdcr = 1;
}

static int pxafb_smart_thread(void *arg)
{
        struct pxafb_info *fbi = arg;
        struct pxafb_mach_info *inf = fbi->inf;

        if (!inf->smart_update) {
                pr_err("%s: not properly initialized, thread terminated\n",
                                __func__);
                return -EINVAL;
        }

        pr_debug("%s(): task starting\n", __func__);

        set_freezable();
        while (!kthread_should_stop()) {

                if (try_to_freeze())
                        continue;

                mutex_lock(&fbi->ctrlr_lock);

                if (fbi->state == C_ENABLE) {
                        inf->smart_update(&fbi->fb);
                        complete(&fbi->refresh_done);
                }

                mutex_unlock(&fbi->ctrlr_lock);

                set_current_state(TASK_INTERRUPTIBLE);
                schedule_timeout(msecs_to_jiffies(30));
        }

        pr_debug("%s(): task ending\n", __func__);
        return 0;
}

static int pxafb_smart_init(struct pxafb_info *fbi)
{
        if (!(fbi->lccr0 & LCCR0_LCDT))
                return 0;

        fbi->smart_cmds = (uint16_t *) fbi->dma_buff->cmd_buff;
        fbi->n_smart_cmds = 0;

        init_completion(&fbi->command_done);
        init_completion(&fbi->refresh_done);

        fbi->smart_thread = kthread_run(pxafb_smart_thread, fbi,
                                        "lcd_refresh");
        if (IS_ERR(fbi->smart_thread)) {
                pr_err("%s: unable to create kernel thread\n", __func__);
                return PTR_ERR(fbi->smart_thread);
        }

        return 0;
}
#else
static inline int pxafb_smart_init(struct pxafb_info *fbi) { return 0; }
#endif /* CONFIG_FB_PXA_SMARTPANEL */

static void setup_parallel_timing(struct pxafb_info *fbi,
                                  struct fb_var_screeninfo *var)
{
        unsigned int lines_per_panel, pcd = get_pcd(fbi, var->pixclock);

        fbi->reg_lccr1 =
                LCCR1_DisWdth(var->xres) +
                LCCR1_HorSnchWdth(var->hsync_len) +
                LCCR1_BegLnDel(var->left_margin) +
                LCCR1_EndLnDel(var->right_margin);

        /*
         * If we have a dual scan LCD, we need to halve
         * the YRES parameter.
         */
        lines_per_panel = var->yres;
        if ((fbi->lccr0 & LCCR0_SDS) == LCCR0_Dual)
                lines_per_panel /= 2;

        fbi->reg_lccr2 =
                LCCR2_DisHght(lines_per_panel) +
                LCCR2_VrtSnchWdth(var->vsync_len) +
                LCCR2_BegFrmDel(var->upper_margin) +
                LCCR2_EndFrmDel(var->lower_margin);

        fbi->reg_lccr3 = fbi->lccr3 |
                (var->sync & FB_SYNC_HOR_HIGH_ACT ?
                 LCCR3_HorSnchH : LCCR3_HorSnchL) |
                (var->sync & FB_SYNC_VERT_HIGH_ACT ?
                 LCCR3_VrtSnchH : LCCR3_VrtSnchL);

        if (pcd) {
                fbi->reg_lccr3 |= LCCR3_PixClkDiv(pcd);
                set_hsync_time(fbi, pcd);
        }
}

/*
 * pxafb_activate_var():
 *      Configures LCD Controller based on entries in var parameter.
 *      Settings are only written to the controller if changes were made.
 */
static int pxafb_activate_var(struct fb_var_screeninfo *var,
                              struct pxafb_info *fbi)
{
        u_long flags;

        /* Update shadow copy atomically */
        local_irq_save(flags);

#ifdef CONFIG_FB_PXA_SMARTPANEL
        if (fbi->lccr0 & LCCR0_LCDT)
                setup_smart_timing(fbi, var);
        else
#endif
                setup_parallel_timing(fbi, var);

        setup_base_frame(fbi, var, 0);

        fbi->reg_lccr0 = fbi->lccr0 |
                (LCCR0_LDM | LCCR0_SFM | LCCR0_IUM | LCCR0_EFM |
                 LCCR0_QDM | LCCR0_BM  | LCCR0_OUM);

        fbi->reg_lccr3 |= pxafb_var_to_lccr3(var);

        fbi->reg_lccr4 = lcd_readl(fbi, LCCR4) & ~LCCR4_PAL_FOR_MASK;
        fbi->reg_lccr4 |= (fbi->lccr4 & LCCR4_PAL_FOR_MASK);
        local_irq_restore(flags);

        /*
         * Only update the registers if the controller is enabled
         * and something has changed.
         */
        if ((lcd_readl(fbi, LCCR0) != fbi->reg_lccr0) ||
            (lcd_readl(fbi, LCCR1) != fbi->reg_lccr1) ||
            (lcd_readl(fbi, LCCR2) != fbi->reg_lccr2) ||
            (lcd_readl(fbi, LCCR3) != fbi->reg_lccr3) ||
            (lcd_readl(fbi, LCCR4) != fbi->reg_lccr4) ||
            (lcd_readl(fbi, FDADR0) != fbi->fdadr[0]) ||
            ((fbi->lccr0 & LCCR0_SDS) &&
            (lcd_readl(fbi, FDADR1) != fbi->fdadr[1])))
                pxafb_schedule_work(fbi, C_REENABLE);

        return 0;
}

/*
 * NOTE!  The following functions are purely helpers for set_ctrlr_state.
 * Do not call them directly; set_ctrlr_state does the correct serialisation
 * to ensure that things happen in the right way 100% of time time.
 *      -- rmk
 */
static inline void __pxafb_backlight_power(struct pxafb_info *fbi, int on)
{
        pr_debug("pxafb: backlight o%s\n", on ? "n" : "ff");

        if (fbi->backlight_power)
                fbi->backlight_power(on);
}

static inline void __pxafb_lcd_power(struct pxafb_info *fbi, int on)
{
        pr_debug("pxafb: LCD power o%s\n", on ? "n" : "ff");

        if (fbi->lcd_power)
                fbi->lcd_power(on, &fbi->fb.var);

        if (fbi->lcd_supply && fbi->lcd_supply_enabled != on) {
                int ret;

                if (on)
                        ret = regulator_enable(fbi->lcd_supply);
                else
                        ret = regulator_disable(fbi->lcd_supply);

                if (ret < 0)
                        pr_warn("Unable to %s LCD supply regulator: %d\n",
                                on ? "enable" : "disable", ret);
                else
                        fbi->lcd_supply_enabled = on;
        }
}

static void pxafb_enable_controller(struct pxafb_info *fbi)
{
        pr_debug("pxafb: Enabling LCD controller\n");
        pr_debug("fdadr0 0x%08x\n", (unsigned int) fbi->fdadr[0]);
        pr_debug("fdadr1 0x%08x\n", (unsigned int) fbi->fdadr[1]);
        pr_debug("reg_lccr0 0x%08x\n", (unsigned int) fbi->reg_lccr0);
        pr_debug("reg_lccr1 0x%08x\n", (unsigned int) fbi->reg_lccr1);
        pr_debug("reg_lccr2 0x%08x\n", (unsigned int) fbi->reg_lccr2);
        pr_debug("reg_lccr3 0x%08x\n", (unsigned int) fbi->reg_lccr3);

        /* enable LCD controller clock */
        if (clk_prepare_enable(fbi->clk)) {
                pr_err("%s: Failed to prepare clock\n", __func__);
                return;
        }

        if (fbi->lccr0 & LCCR0_LCDT)
                return;

        /* Sequence from 11.7.10 */
        lcd_writel(fbi, LCCR4, fbi->reg_lccr4);
        lcd_writel(fbi, LCCR3, fbi->reg_lccr3);
        lcd_writel(fbi, LCCR2, fbi->reg_lccr2);
        lcd_writel(fbi, LCCR1, fbi->reg_lccr1);
        lcd_writel(fbi, LCCR0, fbi->reg_lccr0 & ~LCCR0_ENB);

        lcd_writel(fbi, FDADR0, fbi->fdadr[0]);
        if (fbi->lccr0 & LCCR0_SDS)
                lcd_writel(fbi, FDADR1, fbi->fdadr[1]);
        lcd_writel(fbi, LCCR0, fbi->reg_lccr0 | LCCR0_ENB);
}

static void pxafb_disable_controller(struct pxafb_info *fbi)
{
        uint32_t lccr0;

#ifdef CONFIG_FB_PXA_SMARTPANEL
        if (fbi->lccr0 & LCCR0_LCDT) {
                wait_for_completion_timeout(&fbi->refresh_done,
                                msecs_to_jiffies(200));
                return;
        }
#endif

        /* Clear LCD Status Register */
        lcd_writel(fbi, LCSR, 0xffffffff);

        lccr0 = lcd_readl(fbi, LCCR0) & ~LCCR0_LDM;
        lcd_writel(fbi, LCCR0, lccr0);
        lcd_writel(fbi, LCCR0, lccr0 | LCCR0_DIS);

        wait_for_completion_timeout(&fbi->disable_done, msecs_to_jiffies(200));

        /* disable LCD controller clock */
        clk_disable_unprepare(fbi->clk);
}

/*
 *  pxafb_handle_irq: Handle 'LCD DONE' interrupts.
 */
static irqreturn_t pxafb_handle_irq(int irq, void *dev_id)
{
        struct pxafb_info *fbi = dev_id;
        unsigned int lccr0, lcsr;

        lcsr = lcd_readl(fbi, LCSR);
        if (lcsr & LCSR_LDD) {
                lccr0 = lcd_readl(fbi, LCCR0);
                lcd_writel(fbi, LCCR0, lccr0 | LCCR0_LDM);
                complete(&fbi->disable_done);
        }

#ifdef CONFIG_FB_PXA_SMARTPANEL
        if (lcsr & LCSR_CMD_INT)
                complete(&fbi->command_done);
#endif
        lcd_writel(fbi, LCSR, lcsr);

#ifdef CONFIG_FB_PXA_OVERLAY
        {
                unsigned int lcsr1 = lcd_readl(fbi, LCSR1);
                if (lcsr1 & LCSR1_BS(1))
                        complete(&fbi->overlay[0].branch_done);

                if (lcsr1 & LCSR1_BS(2))
                        complete(&fbi->overlay[1].branch_done);

                lcd_writel(fbi, LCSR1, lcsr1);
        }
#endif
        return IRQ_HANDLED;
}

/*
 * This function must be called from task context only, since it will
 * sleep when disabling the LCD controller, or if we get two contending
 * processes trying to alter state.
 */
static void set_ctrlr_state(struct pxafb_info *fbi, u_int state)
{
        u_int old_state;

        mutex_lock(&fbi->ctrlr_lock);

        old_state = fbi->state;

        /*
         * Hack around fbcon initialisation.
         */
        if (old_state == C_STARTUP && state == C_REENABLE)
                state = C_ENABLE;

        switch (state) {
        case C_DISABLE_CLKCHANGE:
                /*
                 * Disable controller for clock change.  If the
                 * controller is already disabled, then do nothing.
                 */
                if (old_state != C_DISABLE && old_state != C_DISABLE_PM) {
                        fbi->state = state;
                        /* TODO __pxafb_lcd_power(fbi, 0); */
                        pxafb_disable_controller(fbi);
                }
                break;

        case C_DISABLE_PM:
        case C_DISABLE:
                /*
                 * Disable controller
                 */
                if (old_state != C_DISABLE) {
                        fbi->state = state;
                        __pxafb_backlight_power(fbi, 0);
                        __pxafb_lcd_power(fbi, 0);
                        if (old_state != C_DISABLE_CLKCHANGE)
                                pxafb_disable_controller(fbi);
                }
                break;

        case C_ENABLE_CLKCHANGE:
                /*
                 * Enable the controller after clock change.  Only
                 * do this if we were disabled for the clock change.
                 */
                if (old_state == C_DISABLE_CLKCHANGE) {
                        fbi->state = C_ENABLE;
                        pxafb_enable_controller(fbi);
                        /* TODO __pxafb_lcd_power(fbi, 1); */
                }
                break;

        case C_REENABLE:
                /*
                 * Re-enable the controller only if it was already
                 * enabled.  This is so we reprogram the control
                 * registers.
                 */
                if (old_state == C_ENABLE) {
                        __pxafb_lcd_power(fbi, 0);
                        pxafb_disable_controller(fbi);
                        pxafb_enable_controller(fbi);
                        __pxafb_lcd_power(fbi, 1);
                }
                break;

        case C_ENABLE_PM:
                /*
                 * Re-enable the controller after PM.  This is not
                 * perfect - think about the case where we were doing
                 * a clock change, and we suspended half-way through.
                 */
                if (old_state != C_DISABLE_PM)
                        break;
                /* fall through */

        case C_ENABLE:
                /*
                 * Power up the LCD screen, enable controller, and
                 * turn on the backlight.
                 */
                if (old_state != C_ENABLE) {
                        fbi->state = C_ENABLE;
                        pxafb_enable_controller(fbi);
                        __pxafb_lcd_power(fbi, 1);
                        __pxafb_backlight_power(fbi, 1);
                }
                break;
        }
        mutex_unlock(&fbi->ctrlr_lock);
}

/*
 * Our LCD controller task (which is called when we blank or unblank)
 * via keventd.
 */
static void pxafb_task(struct work_struct *work)
{
        struct pxafb_info *fbi =
                container_of(work, struct pxafb_info, task);
        u_int state = xchg(&fbi->task_state, -1);

        set_ctrlr_state(fbi, state);
}

#ifdef CONFIG_CPU_FREQ
/*
 * CPU clock speed change handler.  We need to adjust the LCD timing
 * parameters when the CPU clock is adjusted by the power management
 * subsystem.
 *
 * TODO: Determine why f->new != 10*get_lclk_frequency_10khz()
 */
static int
pxafb_freq_transition(struct notifier_block *nb, unsigned long val, void *data)
{
        struct pxafb_info *fbi = TO_INF(nb, freq_transition);
        /* TODO struct cpufreq_freqs *f = data; */
        u_int pcd;

        switch (val) {
        case CPUFREQ_PRECHANGE:
#ifdef CONFIG_FB_PXA_OVERLAY
                if (!(fbi->overlay[0].usage || fbi->overlay[1].usage))
#endif
                        set_ctrlr_state(fbi, C_DISABLE_CLKCHANGE);
                break;

        case CPUFREQ_POSTCHANGE:
                pcd = get_pcd(fbi, fbi->fb.var.pixclock);
                set_hsync_time(fbi, pcd);
                fbi->reg_lccr3 = (fbi->reg_lccr3 & ~0xff) |
                                  LCCR3_PixClkDiv(pcd);
                set_ctrlr_state(fbi, C_ENABLE_CLKCHANGE);
                break;
        }
        return 0;
}

static int
pxafb_freq_policy(struct notifier_block *nb, unsigned long val, void *data)
{
        struct pxafb_info *fbi = TO_INF(nb, freq_policy);
        struct fb_var_screeninfo *var = &fbi->fb.var;
        struct cpufreq_policy *policy = data;

        switch (val) {
        case CPUFREQ_ADJUST:
                pr_debug("min dma period: %d ps, "
                        "new clock %d kHz\n", pxafb_display_dma_period(var),
                        policy->max);
                /* TODO: fill in min/max values */
                break;
        }
        return 0;
}
#endif

#ifdef CONFIG_PM
/*
 * Power management hooks.  Note that we won't be called from IRQ context,
 * unlike the blank functions above, so we may sleep.
 */
static int pxafb_suspend(struct device *dev)
{
        struct pxafb_info *fbi = dev_get_drvdata(dev);

        set_ctrlr_state(fbi, C_DISABLE_PM);
        return 0;
}

static int pxafb_resume(struct device *dev)
{
        struct pxafb_info *fbi = dev_get_drvdata(dev);

        set_ctrlr_state(fbi, C_ENABLE_PM);
        return 0;
}

static const struct dev_pm_ops pxafb_pm_ops = {
        .suspend        = pxafb_suspend,
        .resume         = pxafb_resume,
};
#endif

static int pxafb_init_video_memory(struct pxafb_info *fbi)
{
        int size = PAGE_ALIGN(fbi->video_mem_size);

        fbi->video_mem = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
        if (fbi->video_mem == NULL)
                return -ENOMEM;

        fbi->video_mem_phys = virt_to_phys(fbi->video_mem);
        fbi->video_mem_size = size;

        fbi->fb.fix.smem_start  = fbi->video_mem_phys;
        fbi->fb.fix.smem_len    = fbi->video_mem_size;
        fbi->fb.screen_base     = fbi->video_mem;

        return fbi->video_mem ? 0 : -ENOMEM;
}

static void pxafb_decode_mach_info(struct pxafb_info *fbi,
                                   struct pxafb_mach_info *inf)
{
        unsigned int lcd_conn = inf->lcd_conn;
        struct pxafb_mode_info *m;
        int i;

        fbi->cmap_inverse       = inf->cmap_inverse;
        fbi->cmap_static        = inf->cmap_static;
        fbi->lccr4              = inf->lccr4;

        switch (lcd_conn & LCD_TYPE_MASK) {
        case LCD_TYPE_MONO_STN:
                fbi->lccr0 = LCCR0_CMS;
                break;
        case LCD_TYPE_MONO_DSTN:
                fbi->lccr0 = LCCR0_CMS | LCCR0_SDS;
                break;
        case LCD_TYPE_COLOR_STN:
                fbi->lccr0 = 0;
                break;
        case LCD_TYPE_COLOR_DSTN:
                fbi->lccr0 = LCCR0_SDS;
                break;
        case LCD_TYPE_COLOR_TFT:
                fbi->lccr0 = LCCR0_PAS;
                break;
        case LCD_TYPE_SMART_PANEL:
                fbi->lccr0 = LCCR0_LCDT | LCCR0_PAS;
                break;
        default:
                /* fall back to backward compatibility way */
                fbi->lccr0 = inf->lccr0;
                fbi->lccr3 = inf->lccr3;
                goto decode_mode;
        }

        if (lcd_conn == LCD_MONO_STN_8BPP)
                fbi->lccr0 |= LCCR0_DPD;

        fbi->lccr0 |= (lcd_conn & LCD_ALTERNATE_MAPPING) ? LCCR0_LDDALT : 0;

        fbi->lccr3 = LCCR3_Acb((inf->lcd_conn >> 10) & 0xff);
        fbi->lccr3 |= (lcd_conn & LCD_BIAS_ACTIVE_LOW) ? LCCR3_OEP : 0;
        fbi->lccr3 |= (lcd_conn & LCD_PCLK_EDGE_FALL)  ? LCCR3_PCP : 0;

decode_mode:
        pxafb_setmode(&fbi->fb.var, &inf->modes[0]);

        /* decide video memory size as follows:
         * 1. default to mode of maximum resolution
         * 2. allow platform to override
         * 3. allow module parameter to override
         */
        for (i = 0, m = &inf->modes[0]; i < inf->num_modes; i++, m++)
                fbi->video_mem_size = max_t(size_t, fbi->video_mem_size,
                                m->xres * m->yres * m->bpp / 8);

        if (inf->video_mem_size > fbi->video_mem_size)
                fbi->video_mem_size = inf->video_mem_size;

        if (video_mem_size > fbi->video_mem_size)
                fbi->video_mem_size = video_mem_size;
}

static struct pxafb_info *pxafb_init_fbinfo(struct device *dev,
                                            struct pxafb_mach_info *inf)
{
        struct pxafb_info *fbi;
        void *addr;

        /* Alloc the pxafb_info and pseudo_palette in one step */
        fbi = devm_kzalloc(dev, sizeof(struct pxafb_info) + sizeof(u32) * 16,
                           GFP_KERNEL);
        if (!fbi)
                return ERR_PTR(-ENOMEM);

        fbi->dev = dev;
        fbi->inf = inf;

        fbi->clk = devm_clk_get(dev, NULL);
        if (IS_ERR(fbi->clk))
                return ERR_CAST(fbi->clk);

        strcpy(fbi->fb.fix.id, PXA_NAME);

        fbi->fb.fix.type        = FB_TYPE_PACKED_PIXELS;
        fbi->fb.fix.type_aux    = 0;
        fbi->fb.fix.xpanstep    = 0;
        fbi->fb.fix.ypanstep    = 1;
        fbi->fb.fix.ywrapstep   = 0;
        fbi->fb.fix.accel       = FB_ACCEL_NONE;

        fbi->fb.var.nonstd      = 0;
        fbi->fb.var.activate    = FB_ACTIVATE_NOW;
        fbi->fb.var.height      = -1;
        fbi->fb.var.width       = -1;
        fbi->fb.var.accel_flags = FB_ACCELF_TEXT;
        fbi->fb.var.vmode       = FB_VMODE_NONINTERLACED;

        fbi->fb.fbops           = &pxafb_ops;
        fbi->fb.flags           = FBINFO_DEFAULT;
        fbi->fb.node            = -1;

        addr = fbi;
        addr = addr + sizeof(struct pxafb_info);
        fbi->fb.pseudo_palette  = addr;

        fbi->state              = C_STARTUP;
        fbi->task_state         = (u_char)-1;

        pxafb_decode_mach_info(fbi, inf);

#ifdef CONFIG_FB_PXA_OVERLAY
        /* place overlay(s) on top of base */
        if (pxafb_overlay_supported())
                fbi->lccr0 |= LCCR0_OUC;
#endif

        init_waitqueue_head(&fbi->ctrlr_wait);
        INIT_WORK(&fbi->task, pxafb_task);
        mutex_init(&fbi->ctrlr_lock);
        init_completion(&fbi->disable_done);

        return fbi;
}

#ifdef CONFIG_FB_PXA_PARAMETERS
static int parse_opt_mode(struct device *dev, const char *this_opt,
                          struct pxafb_mach_info *inf)
{
        const char *name = this_opt+5;
        unsigned int namelen = strlen(name);
        int res_specified = 0, bpp_specified = 0;
        unsigned int xres = 0, yres = 0, bpp = 0;
        int yres_specified = 0;
        int i;
        for (i = namelen-1; i >= 0; i--) {
                switch (name[i]) {
                case '-':
                        namelen = i;
                        if (!bpp_specified && !yres_specified) {
                                bpp = simple_strtoul(&name[i+1], NULL, 0);
                                bpp_specified = 1;
                        } else
                                goto done;
                        break;
                case 'x':
                        if (!yres_specified) {
                                yres = simple_strtoul(&name[i+1], NULL, 0);
                                yres_specified = 1;
                        } else
                                goto done;
                        break;
                case '0' ... '9':
                        break;
                default:
                        goto done;
                }
        }
        if (i < 0 && yres_specified) {
                xres = simple_strtoul(name, NULL, 0);
                res_specified = 1;
        }
done:
        if (res_specified) {
                dev_info(dev, "overriding resolution: %dx%d\n", xres, yres);
                inf->modes[0].xres = xres; inf->modes[0].yres = yres;
        }
        if (bpp_specified)
                switch (bpp) {
                case 1:
                case 2:
                case 4:
                case 8:
                case 16:
                        inf->modes[0].bpp = bpp;
                        dev_info(dev, "overriding bit depth: %d\n", bpp);
                        break;
                default:
                        dev_err(dev, "Depth %d is not valid\n", bpp);
                        return -EINVAL;
                }
        return 0;
}

static int parse_opt(struct device *dev, char *this_opt,
                     struct pxafb_mach_info *inf)
{
        struct pxafb_mode_info *mode = &inf->modes[0];
        char s[64];

        s[0] = '\0';

        if (!strncmp(this_opt, "vmem:", 5)) {
                video_mem_size = memparse(this_opt + 5, NULL);
        } else if (!strncmp(this_opt, "mode:", 5)) {
                return parse_opt_mode(dev, this_opt, inf);
        } else if (!strncmp(this_opt, "pixclock:", 9)) {
                mode->pixclock = simple_strtoul(this_opt+9, NULL, 0);
                sprintf(s, "pixclock: %ld\n", mode->pixclock);
        } else if (!strncmp(this_opt, "left:", 5)) {
                mode->left_margin = simple_strtoul(this_opt+5, NULL, 0);
                sprintf(s, "left: %u\n", mode->left_margin);
        } else if (!strncmp(this_opt, "right:", 6)) {
                mode->right_margin = simple_strtoul(this_opt+6, NULL, 0);
                sprintf(s, "right: %u\n", mode->right_margin);
        } else if (!strncmp(this_opt, "upper:", 6)) {
                mode->upper_margin = simple_strtoul(this_opt+6, NULL, 0);
                sprintf(s, "upper: %u\n", mode->upper_margin);
        } else if (!strncmp(this_opt, "lower:", 6)) {
                mode->lower_margin = simple_strtoul(this_opt+6, NULL, 0);
                sprintf(s, "lower: %u\n", mode->lower_margin);
        } else if (!strncmp(this_opt, "hsynclen:", 9)) {
                mode->hsync_len = simple_strtoul(this_opt+9, NULL, 0);
                sprintf(s, "hsynclen: %u\n", mode->hsync_len);
        } else if (!strncmp(this_opt, "vsynclen:", 9)) {
                mode->vsync_len = simple_strtoul(this_opt+9, NULL, 0);
                sprintf(s, "vsynclen: %u\n", mode->vsync_len);
        } else if (!strncmp(this_opt, "hsync:", 6)) {
                if (simple_strtoul(this_opt+6, NULL, 0) == 0) {
                        sprintf(s, "hsync: Active Low\n");
                        mode->sync &= ~FB_SYNC_HOR_HIGH_ACT;
                } else {
                        sprintf(s, "hsync: Active High\n");
                        mode->sync |= FB_SYNC_HOR_HIGH_ACT;
                }
        } else if (!strncmp(this_opt, "vsync:", 6)) {
                if (simple_strtoul(this_opt+6, NULL, 0) == 0) {
                        sprintf(s, "vsync: Active Low\n");
                        mode->sync &= ~FB_SYNC_VERT_HIGH_ACT;
                } else {
                        sprintf(s, "vsync: Active High\n");
                        mode->sync |= FB_SYNC_VERT_HIGH_ACT;
                }
        } else if (!strncmp(this_opt, "dpc:", 4)) {
                if (simple_strtoul(this_opt+4, NULL, 0) == 0) {
                        sprintf(s, "double pixel clock: false\n");
                        inf->lccr3 &= ~LCCR3_DPC;
                } else {
                        sprintf(s, "double pixel clock: true\n");
                        inf->lccr3 |= LCCR3_DPC;
                }
        } else if (!strncmp(this_opt, "outputen:", 9)) {
                if (simple_strtoul(this_opt+9, NULL, 0) == 0) {
                        sprintf(s, "output enable: active low\n");
                        inf->lccr3 = (inf->lccr3 & ~LCCR3_OEP) | LCCR3_OutEnL;
                } else {
                        sprintf(s, "output enable: active high\n");
                        inf->lccr3 = (inf->lccr3 & ~LCCR3_OEP) | LCCR3_OutEnH;
                }
        } else if (!strncmp(this_opt, "pixclockpol:", 12)) {
                if (simple_strtoul(this_opt+12, NULL, 0) == 0) {
                        sprintf(s, "pixel clock polarity: falling edge\n");
                        inf->lccr3 = (inf->lccr3 & ~LCCR3_PCP) | LCCR3_PixFlEdg;

                } else {
                        sprintf(s, "pixel clock polarity: rising edge\n");
                        inf->lccr3 = (inf->lccr3 & ~LCCR3_PCP) | LCCR3_PixRsEdg;
                }
        } else if (!strncmp(this_opt, "color", 5)) {
                inf->lccr0 = (inf->lccr0 & ~LCCR0_CMS) | LCCR0_Color;
        } else if (!strncmp(this_opt, "mono", 4)) {
                inf->lccr0 = (inf->lccr0 & ~LCCR0_CMS) | LCCR0_Mono;
        } else if (!strncmp(this_opt, "active", 6)) {
                inf->lccr0 = (inf->lccr0 & ~LCCR0_PAS) | LCCR0_Act;
        } else if (!strncmp(this_opt, "passive", 7)) {
                inf->lccr0 = (inf->lccr0 & ~LCCR0_PAS) | LCCR0_Pas;
        } else if (!strncmp(this_opt, "single", 6)) {
                inf->lccr0 = (inf->lccr0 & ~LCCR0_SDS) | LCCR0_Sngl;
        } else if (!strncmp(this_opt, "dual", 4)) {
                inf->lccr0 = (inf->lccr0 & ~LCCR0_SDS) | LCCR0_Dual;
        } else if (!strncmp(this_opt, "4pix", 4)) {
                inf->lccr0 = (inf->lccr0 & ~LCCR0_DPD) | LCCR0_4PixMono;
        } else if (!strncmp(this_opt, "8pix", 4)) {
                inf->lccr0 = (inf->lccr0 & ~LCCR0_DPD) | LCCR0_8PixMono;
        } else {
                dev_err(dev, "unknown option: %s\n", this_opt);
                return -EINVAL;
        }

        if (s[0] != '\0')
                dev_info(dev, "override %s", s);

        return 0;
}

static int pxafb_parse_options(struct device *dev, char *options,
                               struct pxafb_mach_info *inf)
{
        char *this_opt;
        int ret;

        if (!options || !*options)
                return 0;

        dev_dbg(dev, "options are \"%s\"\n", options ? options : "null");

        /* could be made table driven or similar?... */
        while ((this_opt = strsep(&options, ",")) != NULL) {
                ret = parse_opt(dev, this_opt, inf);
                if (ret)
                        return ret;
        }
        return 0;
}

static char g_options[256] = "";

#ifndef MODULE
static int __init pxafb_setup_options(void)
{
        char *options = NULL;

        if (fb_get_options("pxafb", &options))
                return -ENODEV;

        if (options)
                strlcpy(g_options, options, sizeof(g_options));

        return 0;
}
#else
#define pxafb_setup_options()           (0)

module_param_string(options, g_options, sizeof(g_options), 0);
MODULE_PARM_DESC(options, "LCD parameters (see Documentation/fb/pxafb.rst)");
#endif

#else
#define pxafb_parse_options(...)        (0)
#define pxafb_setup_options()           (0)
#endif

#ifdef DEBUG_VAR
/* Check for various illegal bit-combinations. Currently only
 * a warning is given. */
static void pxafb_check_options(struct device *dev, struct pxafb_mach_info *inf)
{
        if (inf->lcd_conn)
                return;

        if (inf->lccr0 & LCCR0_INVALID_CONFIG_MASK)
                dev_warn(dev, "machine LCCR0 setting contains "
                                "illegal bits: %08x\n",
                        inf->lccr0 & LCCR0_INVALID_CONFIG_MASK);
        if (inf->lccr3 & LCCR3_INVALID_CONFIG_MASK)
                dev_warn(dev, "machine LCCR3 setting contains "
                                "illegal bits: %08x\n",
                        inf->lccr3 & LCCR3_INVALID_CONFIG_MASK);
        if (inf->lccr0 & LCCR0_DPD &&
            ((inf->lccr0 & LCCR0_PAS) != LCCR0_Pas ||
             (inf->lccr0 & LCCR0_SDS) != LCCR0_Sngl ||
             (inf->lccr0 & LCCR0_CMS) != LCCR0_Mono))
                dev_warn(dev, "Double Pixel Data (DPD) mode is "
                                "only valid in passive mono"
                                " single panel mode\n");
        if ((inf->lccr0 & LCCR0_PAS) == LCCR0_Act &&
            (inf->lccr0 & LCCR0_SDS) == LCCR0_Dual)
                dev_warn(dev, "Dual panel only valid in passive mode\n");
        if ((inf->lccr0 & LCCR0_PAS) == LCCR0_Pas &&
             (inf->modes->upper_margin || inf->modes->lower_margin))
                dev_warn(dev, "Upper and lower margins must be 0 in "
                                "passive mode\n");
}
#else
#define pxafb_check_options(...)        do {} while (0)
#endif

#if defined(CONFIG_OF)
static const char * const lcd_types[] = {
        "unknown", "mono-stn", "mono-dstn", "color-stn", "color-dstn",
        "color-tft", "smart-panel", NULL
};

static int of_get_pxafb_display(struct device *dev, struct device_node *disp,
                                struct pxafb_mach_info *info, u32 bus_width)
{
        struct display_timings *timings;
        struct videomode vm;
        int i, ret = -EINVAL;
        const char *s;

        ret = of_property_read_string(disp, "lcd-type", &s);
        if (ret)
                s = "color-tft";

        i = match_string(lcd_types, -1, s);
        if (i < 0) {
                dev_err(dev, "lcd-type %s is unknown\n", s);
                return i;
        }
        info->lcd_conn |= LCD_CONN_TYPE(i);
        info->lcd_conn |= LCD_CONN_WIDTH(bus_width);

        timings = of_get_display_timings(disp);
        if (!timings)
                return -EINVAL;

        ret = -ENOMEM;
        info->modes = devm_kcalloc(dev, timings->num_timings,
                                   sizeof(info->modes[0]),
                                   GFP_KERNEL);
        if (!info->modes)
                goto out;
        info->num_modes = timings->num_timings;

        for (i = 0; i < timings->num_timings; i++) {
                ret = videomode_from_timings(timings, &vm, i);
                if (ret) {
                        dev_err(dev, "videomode_from_timings %d failed: %d\n",
                                i, ret);
                        goto out;
                }
                if (vm.flags & DISPLAY_FLAGS_PIXDATA_POSEDGE)
                        info->lcd_conn |= LCD_PCLK_EDGE_RISE;
                if (vm.flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
                        info->lcd_conn |= LCD_PCLK_EDGE_FALL;
                if (vm.flags & DISPLAY_FLAGS_DE_HIGH)
                        info->lcd_conn |= LCD_BIAS_ACTIVE_HIGH;
                if (vm.flags & DISPLAY_FLAGS_DE_LOW)
                        info->lcd_conn |= LCD_BIAS_ACTIVE_LOW;
                if (vm.flags & DISPLAY_FLAGS_HSYNC_HIGH)
                        info->modes[i].sync |= FB_SYNC_HOR_HIGH_ACT;
                if (vm.flags & DISPLAY_FLAGS_VSYNC_HIGH)
                        info->modes[i].sync |= FB_SYNC_VERT_HIGH_ACT;

                info->modes[i].pixclock = 1000000000UL / (vm.pixelclock / 1000);
                info->modes[i].xres = vm.hactive;
                info->modes[i].yres = vm.vactive;
                info->modes[i].hsync_len = vm.hsync_len;
                info->modes[i].left_margin = vm.hback_porch;
                info->modes[i].right_margin = vm.hfront_porch;
                info->modes[i].vsync_len = vm.vsync_len;
                info->modes[i].upper_margin = vm.vback_porch;
                info->modes[i].lower_margin = vm.vfront_porch;
        }
        ret = 0;

out:
        display_timings_release(timings);
        return ret;
}

static int of_get_pxafb_mode_info(struct device *dev,
                                  struct pxafb_mach_info *info)
{
        struct device_node *display, *np;
        u32 bus_width;
        int ret, i;

        np = of_graph_get_next_endpoint(dev->of_node, NULL);
        if (!np) {
                dev_err(dev, "could not find endpoint\n");
                return -EINVAL;
        }
        ret = of_property_read_u32(np, "bus-width", &bus_width);
        if (ret) {
                dev_err(dev, "no bus-width specified: %d\n", ret);
                of_node_put(np);
                return ret;
        }

        display = of_graph_get_remote_port_parent(np);
        of_node_put(np);
        if (!display) {
                dev_err(dev, "no display defined\n");
                return -EINVAL;
        }

        ret = of_get_pxafb_display(dev, display, info, bus_width);
        of_node_put(display);
        if (ret)
                return ret;

        for (i = 0; i < info->num_modes; i++)
                info->modes[i].bpp = bus_width;

        return 0;
}

static struct pxafb_mach_info *of_pxafb_of_mach_info(struct device *dev)
{
        int ret;
        struct pxafb_mach_info *info;

        if (!dev->of_node)
                return NULL;
        info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
        if (!info)
                return ERR_PTR(-ENOMEM);
        ret = of_get_pxafb_mode_info(dev, info);
        if (ret)
                return ERR_PTR(ret);

        /*
         * On purpose, neither lccrX registers nor video memory size can be
         * specified through device-tree, they are considered more a debug hack
         * available through command line.
         */
        return info;
}
#else
static struct pxafb_mach_info *of_pxafb_of_mach_info(struct device *dev)
{
        return NULL;
}
#endif

static int pxafb_probe(struct platform_device *dev)
{
        struct pxafb_info *fbi;
        struct pxafb_mach_info *inf, *pdata;
        struct resource *r;
        int i, irq, ret;

        dev_dbg(&dev->dev, "pxafb_probe\n");

        ret = -ENOMEM;
        pdata = dev_get_platdata(&dev->dev);
        inf = devm_kmalloc(&dev->dev, sizeof(*inf), GFP_KERNEL);
        if (!inf)
                goto failed;

        if (pdata) {
                *inf = *pdata;
                inf->modes =
                        devm_kmalloc_array(&dev->dev, pdata->num_modes,
                                           sizeof(inf->modes[0]), GFP_KERNEL);
                if (!inf->modes)
                        goto failed;
                for (i = 0; i < inf->num_modes; i++)
                        inf->modes[i] = pdata->modes[i];
        }

        if (!pdata)
                inf = of_pxafb_of_mach_info(&dev->dev);
        if (IS_ERR_OR_NULL(inf))
                goto failed;

        ret = pxafb_parse_options(&dev->dev, g_options, inf);
        if (ret < 0)
                goto failed;

        pxafb_check_options(&dev->dev, inf);

        dev_dbg(&dev->dev, "got a %dx%dx%d LCD\n",
                        inf->modes->xres,
                        inf->modes->yres,
                        inf->modes->bpp);
        if (inf->modes->xres == 0 ||
            inf->modes->yres == 0 ||
            inf->modes->bpp == 0) {
                dev_err(&dev->dev, "Invalid resolution or bit depth\n");
                ret = -EINVAL;
                goto failed;
        }

        fbi = pxafb_init_fbinfo(&dev->dev, inf);
        if (IS_ERR(fbi)) {
                dev_err(&dev->dev, "Failed to initialize framebuffer device\n");
                ret = PTR_ERR(fbi);
                goto failed;
        }

        if (cpu_is_pxa3xx() && inf->acceleration_enabled)
                fbi->fb.fix.accel = FB_ACCEL_PXA3XX;

        fbi->backlight_power = inf->pxafb_backlight_power;
        fbi->lcd_power = inf->pxafb_lcd_power;

        fbi->lcd_supply = devm_regulator_get_optional(&dev->dev, "lcd");
        if (IS_ERR(fbi->lcd_supply)) {
                if (PTR_ERR(fbi->lcd_supply) == -EPROBE_DEFER)
                        return -EPROBE_DEFER;

                fbi->lcd_supply = NULL;
        }

        r = platform_get_resource(dev, IORESOURCE_MEM, 0);
        if (r == NULL) {
                dev_err(&dev->dev, "no I/O memory resource defined\n");
                ret = -ENODEV;
                goto failed;
        }

        fbi->mmio_base = devm_ioremap_resource(&dev->dev, r);
        if (IS_ERR(fbi->mmio_base)) {
                dev_err(&dev->dev, "failed to get I/O memory\n");
                ret = -EBUSY;
                goto failed;
        }

        fbi->dma_buff_size = PAGE_ALIGN(sizeof(struct pxafb_dma_buff));
        fbi->dma_buff = dma_alloc_coherent(fbi->dev, fbi->dma_buff_size,
                                &fbi->dma_buff_phys, GFP_KERNEL);
        if (fbi->dma_buff == NULL) {
                dev_err(&dev->dev, "failed to allocate memory for DMA\n");
                ret = -ENOMEM;
                goto failed;
        }

        ret = pxafb_init_video_memory(fbi);
        if (ret) {
                dev_err(&dev->dev, "Failed to allocate video RAM: %d\n", ret);
                ret = -ENOMEM;
                goto failed_free_dma;
        }

        irq = platform_get_irq(dev, 0);
        if (irq < 0) {
                dev_err(&dev->dev, "no IRQ defined\n");
                ret = -ENODEV;
                goto failed_free_mem;
        }

        ret = devm_request_irq(&dev->dev, irq, pxafb_handle_irq, 0, "LCD", fbi);
        if (ret) {
                dev_err(&dev->dev, "request_irq failed: %d\n", ret);
                ret = -EBUSY;
                goto failed_free_mem;
        }

        ret = pxafb_smart_init(fbi);
        if (ret) {
                dev_err(&dev->dev, "failed to initialize smartpanel\n");
                goto failed_free_mem;
        }

        /*
         * This makes sure that our colour bitfield
         * descriptors are correctly initialised.
         */
        ret = pxafb_check_var(&fbi->fb.var, &fbi->fb);
        if (ret) {
                dev_err(&dev->dev, "failed to get suitable mode\n");
                goto failed_free_mem;
        }

        ret = pxafb_set_par(&fbi->fb);
        if (ret) {
                dev_err(&dev->dev, "Failed to set parameters\n");
                goto failed_free_mem;
        }

        platform_set_drvdata(dev, fbi);

        ret = register_framebuffer(&fbi->fb);
        if (ret < 0) {
                dev_err(&dev->dev,
                        "Failed to register framebuffer device: %d\n", ret);
                goto failed_free_cmap;
        }

        pxafb_overlay_init(fbi);

#ifdef CONFIG_CPU_FREQ
        fbi->freq_transition.notifier_call = pxafb_freq_transition;
        fbi->freq_policy.notifier_call = pxafb_freq_policy;
        cpufreq_register_notifier(&fbi->freq_transition,
                                CPUFREQ_TRANSITION_NOTIFIER);
        cpufreq_register_notifier(&fbi->freq_policy,
                                CPUFREQ_POLICY_NOTIFIER);
#endif

        /*
         * Ok, now enable the LCD controller
         */
        set_ctrlr_state(fbi, C_ENABLE);

        return 0;

failed_free_cmap:
        if (fbi->fb.cmap.len)
                fb_dealloc_cmap(&fbi->fb.cmap);
failed_free_mem:
        free_pages_exact(fbi->video_mem, fbi->video_mem_size);
failed_free_dma:
        dma_free_coherent(&dev->dev, fbi->dma_buff_size,
                        fbi->dma_buff, fbi->dma_buff_phys);
failed:
        return ret;
}

static int pxafb_remove(struct platform_device *dev)
{
        struct pxafb_info *fbi = platform_get_drvdata(dev);
        struct fb_info *info;

        if (!fbi)
                return 0;

        info = &fbi->fb;

        pxafb_overlay_exit(fbi);
        unregister_framebuffer(info);

        pxafb_disable_controller(fbi);

        if (fbi->fb.cmap.len)
                fb_dealloc_cmap(&fbi->fb.cmap);

        free_pages_exact(fbi->video_mem, fbi->video_mem_size);

        dma_free_wc(&dev->dev, fbi->dma_buff_size, fbi->dma_buff,
                    fbi->dma_buff_phys);

        return 0;
}

static const struct of_device_id pxafb_of_dev_id[] = {
        { .compatible = "marvell,pxa270-lcdc", },
        { .compatible = "marvell,pxa300-lcdc", },
        { .compatible = "marvell,pxa2xx-lcdc", },
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, pxafb_of_dev_id);

static struct platform_driver pxafb_driver = {
        .probe          = pxafb_probe,
        .remove         = pxafb_remove,
        .driver         = {
                .name   = "pxa2xx-fb",
                .of_match_table = pxafb_of_dev_id,
#ifdef CONFIG_PM
                .pm     = &pxafb_pm_ops,
#endif
        },
};

static int __init pxafb_init(void)
{
        if (pxafb_setup_options())
                return -EINVAL;

        return platform_driver_register(&pxafb_driver);
}

static void __exit pxafb_exit(void)
{
        platform_driver_unregister(&pxafb_driver);
}

module_init(pxafb_init);
module_exit(pxafb_exit);

MODULE_DESCRIPTION("loadable framebuffer driver for PXA");
MODULE_LICENSE("GPL");