ssd1289.c

/*
 * SSD1289 Framebuffer
 *
 *
 * Original: Copyright (c) 2009 Jean-Christian de Rivaz
 *
 * SPI mods, console support, 320x240 instead of 240x320:
 * Copyright (c) 2012 Jeroen Domburg <jeroen@spritesmods.com>
 *
 * Bits and pieces borrowed from the fsl-ssd1289.c:
 * Copyright (C) 2010-2011 Freescale Semiconductor, Inc. All Rights Reserved.
 * Author: Alison Wang <b18965@freescale.com>
 *         Jason Jin <Jason.jin@freescale.com>
 *
 * 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.
 *
 * The Solomon Systech SSD1289 chip drive TFT screen up to 240x320.
 *
 * For direct I/O-mode:
 *
 * This driver expect the SSD1286 to be connected to a 16 bits local bus
 * and to be set in the 16 bits parallel interface mode. To use it you must
 * define in your board file a struct platform_device with a name set to
 * "ssd1289" and a struct resource array with two IORESOURCE_MEM: the first
 * for the control register; the second for the data register.
 *
 * For SPI mode:
 *
 * A SPI port with modalias 'ssd1289' should exist. The LCD should be in 16-bit
 * mode (which they usually are hardwired to be...) and connected to three
 * CD4094s and a CD4020. For schematic, check out
 * http://spritesmods.com/?art=spitft
 *
 * LCDs in their own, native SPI mode aren't supported yet, mostly because I
 * can't get my hands on a cheap one.
 */

#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/fb.h>
#include <asm/io.h>
#include <linux/spi/spi.h>

#define SSD1289_REG_OSCILLATION      0x00
#define SSD1289_REG_DRIVER_OUT_CTRL  0x01
#define SSD1289_REG_LCD_DRIVE_AC     0x02
#define SSD1289_REG_POWER_CTRL_1     0x03
#define SSD1289_REG_DISPLAY_CTRL     0x07
#define SSD1289_REG_FRAME_CYCLE      0x0b
#define SSD1289_REG_POWER_CTRL_2     0x0c
#define SSD1289_REG_POWER_CTRL_3     0x0d
#define SSD1289_REG_POWER_CTRL_4     0x0e
#define SSD1289_REG_GATE_SCAN_START  0x0f
#define SSD1289_REG_SLEEP_MODE       0x10
#define SSD1289_REG_ENTRY_MODE       0x11
#define SSD1289_REG_POWER_CTRL_5     0x1e
#define SSD1289_REG_GDDRAM_DATA      0x22
#define SSD1289_REG_WR_DATA_MASK_1   0x23
#define SSD1289_REG_WR_DATA_MASK_2   0x24
#define SSD1289_REG_FRAME_FREQUENCY  0x25
#define SSD1289_REG_GAMMA_CTRL_1     0x30
#define SSD1289_REG_GAMME_CTRL_2     0x31
#define SSD1289_REG_GAMMA_CTRL_3     0x32
#define SSD1289_REG_GAMMA_CTRL_4     0x33
#define SSD1289_REG_GAMMA_CTRL_5     0x34
#define SSD1289_REG_GAMMA_CTRL_6     0x35
#define SSD1289_REG_GAMMA_CTRL_7     0x36
#define SSD1289_REG_GAMMA_CTRL_8     0x37
#define SSD1289_REG_GAMMA_CTRL_9     0x3a
#define SSD1289_REG_GAMMA_CTRL_10    0x3b
#define SSD1289_REG_V_SCROLL_CTRL_1  0x41
#define SSD1289_REG_V_SCROLL_CTRL_2  0x42
#define SSD1289_REG_H_RAM_ADR_POS    0x44
#define SSD1289_REG_V_RAM_ADR_START  0x45
#define SSD1289_REG_V_RAM_ADR_END    0x46
#define SSD1289_REG_FIRST_WIN_START  0x48
#define SSD1289_REG_FIRST_WIN_END    0x49
#define SSD1289_REG_SECND_WIN_START  0x4a
#define SSD1289_REG_SECND_WIN_END    0x4b
#define SSD1289_REG_GDDRAM_X_ADDR    0x4e
#define SSD1289_REG_GDDRAM_Y_ADDR    0x4f

struct ssd1289_page {
    unsigned short x;
    unsigned short y;
    unsigned short *buffer;
    unsigned short len;
    int must_update;
};

struct ssd1289 {
    struct device *dev;
#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
    volatile unsigned short *ctrl_io;
    volatile unsigned short *data_io;
#elif defined(CONFIG_SSD1289_SPI_MODE)
    struct spi_device *spidev;
#endif
    struct fb_info *info;
    unsigned int pages_count;
    struct ssd1289_page *pages;
    unsigned long pseudo_palette[17];
    int backlight;
};


#if defined(CONFIG_SSD1289_SPI_MODE)
/*
These two routines will write to the SPI-port, shifting data into the 4094 shift
registers.
*/
#define CD4094_RD (1<<0)
#define CD4094_WR (1<<1)
#define CD4094_BCNT (1<<2)
#define CD4094_RST (1<<3)
#define CD4094_DC (1<<4)
#define CD4094_INVERT (CD4094_RD|CD4094_WR|CD4094_RST)

/*
This routine will write a single 16-bit value, either as data or as a command
(depends on isdata). The LCD will clock this in because the SPIs /CS goes high.
*/
static int ssd1289_spi_write(struct ssd1289 *item, unsigned short value,
                unsigned int isdata)
{
    u8 buf[3];
    buf[0]=((isdata?CD4094_DC:0)|CD4094_WR|(item->backlight?CD4094_BCNT:0))^CD4094_INVERT;
    buf[1]=(value>>8)&0xff;
    buf[2]=(value)&0xff;
    spi_write(item->spidev, buf, 3);
    return 0;
}

#define BLOCKLEN (4096)
static u8 ssd1289_spiblock[BLOCKLEN*4];

/*
This routine will clock in len words of data. The LCD will clock this in every 4th byte written
because a 4020 will pull down the /cs at that moment.
*/
static int ssd1289_spi_write_datablock(struct ssd1289 *item,
                    unsigned short *block, int len)
{
    int x;
    unsigned short value;

    //ToDo: send in parts if needed
    if (len>BLOCKLEN) {
        dev_err(item->dev, "%s: len > blocklen (%i > %i)\n",
            __func__, len, BLOCKLEN);
        len=BLOCKLEN;
    }

    for (x=0; x<len; x++) {
        value=block[x];
        ssd1289_spiblock[(x*4)]=0; //dummy
        ssd1289_spiblock[(x*4)+1]=(CD4094_DC|CD4094_WR|(item->backlight?CD4094_BCNT:0))^CD4094_INVERT;
        ssd1289_spiblock[(x*4)+2]=(value>>8)&0xff;
        ssd1289_spiblock[(x*4)+3]=(value)&0xff;
    }
    spi_write(item->spidev, ssd1289_spiblock, len*4);
    return 0;
}
#endif


static inline void ssd1289_reg_set(struct ssd1289 *item, unsigned char reg,
                   unsigned short value)
{
#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
    unsigned short ctrl = reg & 0x00ff;
    writew(ctrl, item->ctrl_io);
    writew(value, item->data_io);
#elif defined(CONFIG_SSD1289_SPI_MODE)
    ssd1289_spi_write(item, reg&0xff, 0);
    ssd1289_spi_write(item, value, 1);
#endif
}

static void ssd1289_copy(struct ssd1289 *item, unsigned int index)
{
    unsigned short x;
    unsigned short y;
    unsigned short *buffer;
    unsigned int len;
#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
    unsigned int count;
#endif
    x = item->pages[index].x;
    y = item->pages[index].y;
    buffer = item->pages[index].buffer;
    len = item->pages[index].len;
    dev_dbg(item->dev,
        "%s: page[%u]: x=%3hu y=%3hu buffer=0x%p len=%3hu\n",
        __func__, index, x, y, buffer, len);

    ssd1289_reg_set(item, SSD1289_REG_GDDRAM_X_ADDR, (item->info->var.yres - 1)-y);
    ssd1289_reg_set(item, SSD1289_REG_GDDRAM_Y_ADDR, x);
#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
    writew(SSD1289_REG_GDDRAM_DATA, item->ctrl_io);
    for (count = 0; count < len; count++) {
        writew(buffer[count], item->data_io);
    }
#elif defined(CONFIG_SSD1289_SPI_MODE)
    ssd1289_spi_write(item, SSD1289_REG_GDDRAM_DATA, 0);

    ssd1289_spi_write_datablock(item, buffer, len);
/*
//The write_datablock can also be exchanged with this code, which is slower but
//doesn't require the CD4020 counter IC.
    for (count = 0; count < len; count++) {
        ssd1289_spi_write(item, buffer[count], 1);
    }
*/
#endif
}

static void ssd1289_update_all(struct ssd1289 *item)
{
    unsigned short i;
    struct fb_deferred_io *fbdefio = item->info->fbdefio;
    for (i = 0; i < item->pages_count; i++) {
        item->pages[i].must_update=1;
    }
    schedule_delayed_work(&item->info->deferred_work, fbdefio->delay);
}

static void ssd1289_update(struct fb_info *info, struct list_head *pagelist)
{
    struct ssd1289 *item = (struct ssd1289 *)info->par;
    struct page *page;
    int i;

    //We can be called because of pagefaults (mmap'ed framebuffer, pages
    //returned in *pagelist) or because of kernel activity
    //(pages[i]/must_update!=0). Add the former to the list of the latter.
    list_for_each_entry(page, pagelist, lru) {
        item->pages[page->index].must_update=1;
    }

    //Copy changed pages.
    for (i=0; i<item->pages_count; i++) {
        //ToDo: Small race here between checking and setting must_update,
        //maybe lock?
        if (item->pages[i].must_update) {
            item->pages[i].must_update=0;
            ssd1289_copy(item, i);
        }
    }

}


static void __init ssd1289_setup(struct ssd1289 *item)
{
    dev_dbg(item->dev, "%s: item=0x%p\n", __func__, (void *)item);
    // OSCEN=1
    ssd1289_reg_set(item, SSD1289_REG_OSCILLATION, 0x0001);
    // DCT=b1010=fosc/4 BT=b001=VGH:+6,VGL:-4
    // DC=b1010=fosc/4 AP=b010=small to medium
    ssd1289_reg_set(item, SSD1289_REG_POWER_CTRL_1, 0xa2a4);
    // VRC=b100:5.5V
    ssd1289_reg_set(item, SSD1289_REG_POWER_CTRL_2, 0x0004);
    // VRH=b1000:Vref*2.165
    ssd1289_reg_set(item, SSD1289_REG_POWER_CTRL_3, 0x0308);
    // VCOMG=1 VDV=b1000:VLCD63*1.05
    ssd1289_reg_set(item, SSD1289_REG_POWER_CTRL_4, 0x3000);
    // nOTP=1 VCM=0x2a:VLCD63*0.77
    ssd1289_reg_set(item, SSD1289_REG_POWER_CTRL_5, 0x00ea);
    // RL=0 REV=1 CAD=0 BGR=1 SM=0 TB=1 MUX=0x13f=319
    ssd1289_reg_set(item, SSD1289_REG_DRIVER_OUT_CTRL, 0x2b3f);
    // FLD=0 ENWS=0 D/C=1 EOR=1 WSMD=0 NW=0x00=0
    ssd1289_reg_set(item, SSD1289_REG_LCD_DRIVE_AC, 0x0600);
    // SLP=0
    ssd1289_reg_set(item, SSD1289_REG_SLEEP_MODE, 0x0000);
    // VSMode=0 DFM=3:65k TRAMS=0 OEDef=0 WMode=0 Dmode=0
    // TY=0 ID=2 AM=1 LG=0 (orig: ID=3, AM=0)
//  ssd1289_reg_set(item, SSD1289_REG_ENTRY_MODE, 0x6030);
    ssd1289_reg_set(item, SSD1289_REG_ENTRY_MODE, 0x6028);
    // PT=0 VLE=1 SPT=0 GON=1 DTE=1 CM=0 D=3
    ssd1289_reg_set(item, SSD1289_REG_DISPLAY_CTRL, 0x0233);
    // NO=0 SDT=0 EQ=0 DIV=0 SDIV=1 SRTN=1 RTN=9:25 clock
    ssd1289_reg_set(item, SSD1289_REG_FRAME_CYCLE, 0x0039);
    // SCN=0
    ssd1289_reg_set(item, SSD1289_REG_GATE_SCAN_START, 0x0000);

    // PKP1=7 PKP0=7
    ssd1289_reg_set(item, SSD1289_REG_GAMMA_CTRL_1, 0x0707);
    // PKP3=2 PKP2=4
    ssd1289_reg_set(item, SSD1289_REG_GAMME_CTRL_2, 0x0204);
    // PKP5=2 PKP4=2
    ssd1289_reg_set(item, SSD1289_REG_GAMMA_CTRL_3, 0x0204);
    // PRP1=5 PRP0=2
    ssd1289_reg_set(item, SSD1289_REG_GAMMA_CTRL_4, 0x0502);
    // PKN1=5 PKN0=7
    ssd1289_reg_set(item, SSD1289_REG_GAMMA_CTRL_5, 0x0507);
    // PKN3=2 PNN2=4
    ssd1289_reg_set(item, SSD1289_REG_GAMMA_CTRL_6, 0x0204);
    // PKN5=2 PKN4=4
    ssd1289_reg_set(item, SSD1289_REG_GAMMA_CTRL_7, 0x0204);
    // PRN1=5 PRN0=2
    ssd1289_reg_set(item, SSD1289_REG_GAMMA_CTRL_8, 0x0502);
    // VRP1=3 VRP0=2
    ssd1289_reg_set(item, SSD1289_REG_GAMMA_CTRL_9, 0x0302);
    // VRN1=3 VRN0=2
    ssd1289_reg_set(item, SSD1289_REG_GAMMA_CTRL_10, 0x0302);

    // WMR=0 WMG=0
    ssd1289_reg_set(item, SSD1289_REG_WR_DATA_MASK_1, 0x0000);
    // WMB=0
    ssd1289_reg_set(item, SSD1289_REG_WR_DATA_MASK_2, 0x0000);
    // OSC=b1010:548k
    ssd1289_reg_set(item, SSD1289_REG_FRAME_FREQUENCY, 0xa000);
    // SS1=0
    ssd1289_reg_set(item, SSD1289_REG_FIRST_WIN_START, 0x0000);
    // SE1=319
    ssd1289_reg_set(item, SSD1289_REG_FIRST_WIN_END,
            (item->info->var.xres - 1));
    // SS2=0
    ssd1289_reg_set(item, SSD1289_REG_SECND_WIN_START, 0x0000);
    // SE2=0
    ssd1289_reg_set(item, SSD1289_REG_SECND_WIN_END, 0x0000);
    // VL1=0
    ssd1289_reg_set(item, SSD1289_REG_V_SCROLL_CTRL_1, 0x0000);
    // VL2=0
    ssd1289_reg_set(item, SSD1289_REG_V_SCROLL_CTRL_2, 0x0000);
    // HEA=0xef=239 HSA=0
    ssd1289_reg_set(item, SSD1289_REG_H_RAM_ADR_POS,
            (item->info->var.yres - 1) << 8);
    // VSA=0
    ssd1289_reg_set(item, SSD1289_REG_V_RAM_ADR_START, 0x0000);
    // VEA=0x13f=319
    ssd1289_reg_set(item, SSD1289_REG_V_RAM_ADR_END,
            (item->info->var.xres - 1));
}

//This routine will allocate the buffer for the complete framebuffer. This
//is one continuous chunk of 16-bit pixel values; userspace programs
//will write here.
static int __init ssd1289_video_alloc(struct ssd1289 *item)
{
    unsigned int frame_size;

    dev_dbg(item->dev, "%s: item=0x%p\n", __func__, (void *)item);

    frame_size = item->info->fix.line_length * item->info->var.yres;
    dev_dbg(item->dev, "%s: item=0x%p frame_size=%u\n",
        __func__, (void *)item, frame_size);

    item->pages_count = frame_size / PAGE_SIZE;
    if ((item->pages_count * PAGE_SIZE) < frame_size) {
        item->pages_count++;
    }
    dev_dbg(item->dev, "%s: item=0x%p pages_count=%u\n",
        __func__, (void *)item, item->pages_count);

    item->info->fix.smem_len = item->pages_count * PAGE_SIZE;
    item->info->fix.smem_start =
        (unsigned long)vmalloc(item->info->fix.smem_len);
    if (!item->info->fix.smem_start) {
        dev_err(item->dev, "%s: unable to vmalloc\n", __func__);
        return -ENOMEM;
    }
    memset((void *)item->info->fix.smem_start, 0, item->info->fix.smem_len);

    return 0;
}

static void ssd1289_video_free(struct ssd1289 *item)
{
    dev_dbg(item->dev, "%s: item=0x%p\n", __func__, (void *)item);
    vfree((void *)item->info->fix.smem_start);
}

//This routine will allocate a ssd1289_page struct for each vm page in the
//main framebuffer memory. Each struct will contain a pointer to the page
//start, an x- and y-offset, and the length of the pagebuffer which is in the framebuffer.
static int __init ssd1289_pages_alloc(struct ssd1289 *item)
{
    unsigned short pixels_per_page;
    unsigned short yoffset_per_page;
    unsigned short xoffset_per_page;
    unsigned short index;
    unsigned short x = 0;
    unsigned short y = 0;
    unsigned short *buffer;
    unsigned int len;

    dev_dbg(item->dev, "%s: item=0x%p\n", __func__, (void *)item);

    item->pages = kmalloc(item->pages_count * sizeof(struct ssd1289_page),
                  GFP_KERNEL);
    if (!item->pages) {
        dev_err(item->dev, "%s: unable to kmalloc for ssd1289_page\n",
            __func__);
        return -ENOMEM;
    }

    pixels_per_page = PAGE_SIZE / (item->info->var.bits_per_pixel / 8);
    yoffset_per_page = pixels_per_page / item->info->var.xres;
    xoffset_per_page = pixels_per_page -
        (yoffset_per_page * item->info->var.xres);
    dev_dbg(item->dev, "%s: item=0x%p pixels_per_page=%hu "
        "yoffset_per_page=%hu xoffset_per_page=%hu\n",
        __func__, (void *)item, pixels_per_page,
        yoffset_per_page, xoffset_per_page);

    buffer = (unsigned short *)item->info->fix.smem_start;
    for (index = 0; index < item->pages_count; index++) {
        len = (item->info->var.xres * item->info->var.yres) -
            (index * pixels_per_page);
        if (len > pixels_per_page) {
            len = pixels_per_page;
        }
        dev_dbg(item->dev,
            "%s: page[%d]: x=%3hu y=%3hu buffer=0x%p len=%3hu\n",
            __func__, index, x, y, buffer, len);
        item->pages[index].x = x;
        item->pages[index].y = y;
        item->pages[index].buffer = buffer;
        item->pages[index].len = len;

        x += xoffset_per_page;
        if (x >= item->info->var.xres) {
            y++;
            x -= item->info->var.xres;
        }
        y += yoffset_per_page;
        buffer += pixels_per_page;
    }

    return 0;
}

static void ssd1289_pages_free(struct ssd1289 *item)
{
    dev_dbg(item->dev, "%s: item=0x%p\n", __func__, (void *)item);

    kfree(item->pages);
}

static inline __u32 CNVT_TOHW(__u32 val, __u32 width)
{
    return ((val<<width) + 0x7FFF - val)>>16;
}

//This routine is needed because the console driver won't work without it.
static int ssd1289_setcolreg(unsigned regno,
                   unsigned red, unsigned green, unsigned blue,
                   unsigned transp, struct fb_info *info)
{
    int ret = 1;

    /*
     * If greyscale is true, then we convert the RGB value
     * to greyscale no matter what visual we are using.
     */
    if (info->var.grayscale)
        red = green = blue = (19595 * red + 38470 * green +
                      7471 * blue) >> 16;
    switch (info->fix.visual) {
    case FB_VISUAL_TRUECOLOR:
        if (regno < 16) {
            u32 *pal = info->pseudo_palette;
            u32 value;

            red = CNVT_TOHW(red, info->var.red.length);
            green = CNVT_TOHW(green, info->var.green.length);
            blue = CNVT_TOHW(blue, info->var.blue.length);
            transp = CNVT_TOHW(transp, info->var.transp.length);

            value = (red << info->var.red.offset) |
                (green << info->var.green.offset) |
                (blue << info->var.blue.offset) |
                (transp << info->var.transp.offset);

            pal[regno] = value;
            ret = 0;
        }
        break;
    case FB_VISUAL_STATIC_PSEUDOCOLOR:
    case FB_VISUAL_PSEUDOCOLOR:
        break;
    }
    return ret;
}

static int ssd1289_blank(int blank_mode, struct fb_info *info)
{
    struct ssd1289 *item = (struct ssd1289 *)info->par;
    if (blank_mode == FB_BLANK_UNBLANK)
        item->backlight=1;
    else
        item->backlight=0;
    //Item->backlight won't take effect until the LCD is written to. Force that
    //by dirty'ing a page.
    item->pages[0].must_update=1;
    schedule_delayed_work(&info->deferred_work, 0);
    return 0;
}

static void ssd1289_touch(struct fb_info *info, int x, int y, int w, int h)
{
    struct fb_deferred_io *fbdefio = info->fbdefio;
    struct ssd1289 *item = (struct ssd1289 *)info->par;
    int i, ystart, yend;
    if (fbdefio) {
        //Touch the pages the y-range hits, so the deferred io will update them.
        for (i=0; i<item->pages_count; i++) {
            ystart=item->pages[i].y;
            yend=item->pages[i].y+(item->pages[i].len/info->fix.line_length)+1;
            if (!((y+h)<ystart || y>yend)) {
                item->pages[i].must_update=1;
            }
        }
        //Schedule the deferred IO to kick in after a delay.
        schedule_delayed_work(&info->deferred_work, fbdefio->delay);
    }
}

static void ssd1289_fillrect(struct fb_info *p, const struct fb_fillrect *rect)
{
    sys_fillrect(p, rect);
    ssd1289_touch(p, rect->dx, rect->dy, rect->width, rect->height);
}

static void ssd1289_imageblit(struct fb_info *p, const struct fb_image *image)
{
    sys_imageblit(p, image);
    ssd1289_touch(p, image->dx, image->dy, image->width, image->height);
}

static void ssd1289_copyarea(struct fb_info *p, const struct fb_copyarea *area)
{
    sys_copyarea(p, area);
    ssd1289_touch(p, area->dx, area->dy, area->width, area->height);
}

static ssize_t ssd1289_write(struct fb_info *p, const char __user *buf,
                size_t count, loff_t *ppos)
{
    ssize_t res;
    res = fb_sys_write(p, buf, count, ppos);
    ssd1289_touch(p, 0, 0, p->var.xres, p->var.yres);
    return res;
}

static struct fb_ops ssd1289_fbops = {
    .owner        = THIS_MODULE,
    .fb_read      = fb_sys_read,
    .fb_write     = ssd1289_write,
    .fb_fillrect  = ssd1289_fillrect,
    .fb_copyarea  = ssd1289_copyarea,
    .fb_imageblit = ssd1289_imageblit,
    .fb_setcolreg   = ssd1289_setcolreg,
    .fb_blank   = ssd1289_blank,
};

static struct fb_fix_screeninfo ssd1289_fix __initdata = {
    .id          = "SSD1289",
    .type        = FB_TYPE_PACKED_PIXELS,
    .visual      = FB_VISUAL_TRUECOLOR,
    .accel       = FB_ACCEL_NONE,
    .line_length = 320 * 2,
};

static struct fb_var_screeninfo ssd1289_var __initdata = {
    .xres       = 320,
    .yres       = 240,
    .xres_virtual   = 320,
    .yres_virtual   = 240,
    .width      = 320,
    .height     = 240,
    .bits_per_pixel = 16,
    .red        = {11, 5, 0},
    .green      = {5, 6, 0},
    .blue       = {0, 5, 0},
    .activate   = FB_ACTIVATE_NOW,
    .vmode      = FB_VMODE_NONINTERLACED,
};

static struct fb_deferred_io ssd1289_defio = {
        .delay          = HZ / 20,
        .deferred_io    = &ssd1289_update,
};

#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
static int __devinit ssd1289_probe(struct platform_device *dev)
#elif defined(CONFIG_SSD1289_SPI_MODE)
static int __devinit ssd1289_probe(struct spi_device *dev)
#endif
{
    int ret = 0;
    struct ssd1289 *item;
#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
    struct resource *ctrl_res;
    struct resource *data_res;
    unsigned int ctrl_res_size;
    unsigned int data_res_size;
    struct resource *ctrl_req;
    struct resource *data_req;
    unsigned short signature;
#endif
    struct fb_info *info;

    dev_dbg(&dev->dev, "%s\n", __func__);

    item = kzalloc(sizeof(struct ssd1289), GFP_KERNEL);
    if (!item) {
        dev_err(&dev->dev,
            "%s: unable to kzalloc for ssd1289\n", __func__);
        ret = -ENOMEM;
        goto out;
    }
    item->dev = &dev->dev;
    dev_set_drvdata(&dev->dev, item);
    item->backlight=1;

#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
    ctrl_res = platform_get_resource(dev, IORESOURCE_MEM, 0);
    if (!ctrl_res) {
        dev_err(&dev->dev,
            "%s: unable to platform_get_resource for ctrl_res\n",
            __func__);
        ret = -ENOENT;
        goto out_item;
    }
    ctrl_res_size = ctrl_res->end - ctrl_res->start + 1;
    ctrl_req = request_mem_region(ctrl_res->start, ctrl_res_size,
                      dev->name);
    if (!ctrl_req) {
        dev_err(&dev->dev,
            "%s: unable to request_mem_region for ctrl_req\n",
            __func__);
        ret = -EIO;
        goto out_item;
    }
    item->ctrl_io = ioremap(ctrl_res->start, ctrl_res_size);
    if (!item->ctrl_io) {
        ret = -EINVAL;
        dev_err(&dev->dev,
            "%s: unable to ioremap for ctrl_io\n", __func__);
        goto out_item;
    }

    data_res = platform_get_resource(dev, IORESOURCE_MEM, 1);
    if (!data_res) {
        dev_err(&dev->dev,
            "%s: unable to platform_get_resource for data_res\n",
            __func__);
        ret = -ENOENT;
        goto out_item;
    }
    data_res_size = data_res->end - data_res->start + 1;
    data_req = request_mem_region(data_res->start,
                      data_res_size, dev->name);
    if (!data_req) {
        dev_err(&dev->dev,
            "%s: unable to request_mem_region for data_req\n",
            __func__);
        ret = -EIO;
        goto out_item;
    }
    item->data_io = ioremap(data_res->start, data_res_size);
    if (!item->data_io) {
        ret = -EINVAL;
        dev_err(&dev->dev,
            "%s: unable to ioremap for data_io\n", __func__);
        goto out_item;
    }

    dev_dbg(&dev->dev, "%s: ctrl_io=%p data_io=%p\n",
        __func__, item->ctrl_io, item->data_io);

    signature = readw(item->ctrl_io);
    dev_dbg(&dev->dev, "%s: signature=0x%04x\n", __func__, signature);
    if (signature != 0x8989) {
        ret = -ENODEV;
        dev_err(&dev->dev,
            "%s: unknown signature 0x%04x\n", __func__, signature);
        goto out_item;
    }

    dev_info(&dev->dev, "item=0x%p ctrl=0x%p data=0x%p\n", (void *)item,
         (void *)ctrl_res->start, (void *)data_res->start);
#elif defined(CONFIG_SSD1289_SPI_MODE)
    item->spidev=dev;
    item->dev=&dev->dev;
    dev_set_drvdata(&dev->dev, item);
    dev_info(&dev->dev, "spi registered, item=0x%p\n", (void *)item);
#endif

    info = framebuffer_alloc(sizeof(struct ssd1289), &dev->dev);
    if (!info) {
        ret = -ENOMEM;
        dev_err(&dev->dev,
            "%s: unable to framebuffer_alloc\n", __func__);
        goto out_item;
    }
    info->pseudo_palette = &item->pseudo_palette;
    item->info = info;
    info->par = item;
    info->dev = &dev->dev;
    info->fbops = &ssd1289_fbops;
    info->flags = FBINFO_FLAG_DEFAULT|FBINFO_VIRTFB;
    info->fix = ssd1289_fix;
    info->var = ssd1289_var;

    ret = ssd1289_video_alloc(item);
    if (ret) {
        dev_err(&dev->dev,
            "%s: unable to ssd1289_video_alloc\n", __func__);
        goto out_info;
    }
    info->screen_base = (char __iomem *)item->info->fix.smem_start;

    ret = ssd1289_pages_alloc(item);
    if (ret < 0) {
        dev_err(&dev->dev,
            "%s: unable to ssd1289_pages_init\n", __func__);
        goto out_video;
    }

    info->fbdefio = &ssd1289_defio;
    fb_deferred_io_init(info);

    ret = register_framebuffer(info);
    if (ret < 0) {
        dev_err(&dev->dev,
            "%s: unable to register_frambuffer\n", __func__);
        goto out_pages;
    }


    ssd1289_setup(item);
    ssd1289_update_all(item);

    return ret;

out_pages:
    ssd1289_pages_free(item);
out_video:
    ssd1289_video_free(item);
out_info:
    framebuffer_release(info);
out_item:
    kfree(item);
out:
    return ret;
}

#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
static int __devexit ssd1289_remove(struct platform_device *dev)
#elif defined(CONFIG_SSD1289_SPI_MODE)
static int __devexit ssd1289_remove(struct spi_device *dev)
#endif
{
    struct ssd1289 *item = dev_get_drvdata(&dev->dev);
    struct fb_info *info;

    dev_dbg(&dev->dev, "%s\n", __func__);

    dev_set_drvdata(&dev->dev, NULL);
    if (item) {
        info = item->info;
        if (info)
            unregister_framebuffer(info);
        ssd1289_pages_free(item);
        ssd1289_video_free(item);
        kfree(item);
        if (info)
            framebuffer_release(info);
    }
    return 0;
}

#ifdef CONFIG_PM
static int ssd1289_suspend(struct spi_device *spi, pm_message_t state)
{
    struct fb_info *info = dev_get_drvdata(&spi->dev);
    struct ssd1289 *item = (struct ssd1289 *)info->par;
    /* enter into sleep mode */
    ssd1289_reg_set(item, SSD1289_REG_SLEEP_MODE, 0x0001);
    return 0;
}

static int ssd1289_resume(struct spi_device *spi)
{
    struct fb_info *info = dev_get_drvdata(&spi->dev);
    struct ssd1289 *item = (struct ssd1289 *)info->par;
    /* leave sleep mode */
    ssd1289_reg_set(item, SSD1289_REG_SLEEP_MODE, 0x0000);
    return 0;
}
#else
#define ssd1289_suspend NULL
#define ssd1289_resume NULL
#endif

#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
static struct platform_driver ssd1289_driver = {
    .probe = ssd1289_probe,
    .driver = {
           .name = "ssd1289",
           },
};
#elif defined(CONFIG_SSD1289_SPI_MODE)
static struct spi_driver spi_ssd1289_driver = {
    .driver = {
        .name   = "spi-ssd1289",
        .bus    = &spi_bus_type,
        .owner  = THIS_MODULE,
    },
    .probe = ssd1289_probe,
    .remove = ssd1289_remove,
    .suspend = ssd1289_suspend,
    .resume = ssd1289_resume,
};
#endif

static int __init ssd1289_init(void)
{
    int ret = 0;

    pr_debug("%s\n", __func__);

#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
    ret = platform_driver_register(&ssd1289_driver);
#elif defined(CONFIG_SSD1289_SPI_MODE)
    ret = spi_register_driver(&spi_ssd1289_driver);
#endif
    if (ret) {
        pr_err("%s: unable to platform_driver_register\n", __func__);
    }

    return ret;
}

static void __exit ssd1289_exit(void)
{
    pr_debug("%s\n", __func__);

#if defined(CONFIG_SSD1289_DIRECTIO_MODE)
    platform_driver_unregister(&ssd1289_driver);
#elif defined(CONFIG_SSD1289_SPI_MODE)
    spi_unregister_driver(&spi_ssd1289_driver);
#endif

}

module_init(ssd1289_init);
module_exit(ssd1289_exit);

MODULE_DESCRIPTION("SSD1289 LCD Driver");
MODULE_AUTHOR("Jeroen Domburg <jeroen@spritesmods.com>");
MODULE_LICENSE("GPL");