Committer: Michael Beasley <mike@snafu.setup>

[mikesnafu-overlay.git] / drivers / video / xilinxfb.c

/*
 * xilinxfb.c
 *
 * Xilinx TFT LCD frame buffer driver
 *
 * Author: MontaVista Software, Inc.
 *         source@mvista.com
 *
 * 2002-2007 (c) MontaVista Software, Inc.
 * 2007 (c) Secret Lab Technologies, Ltd.
 *
 * This file is licensed under the terms of the GNU General Public License
 * version 2.  This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.
 */

/*
 * This driver was based on au1100fb.c by MontaVista rewritten for 2.6
 * by Embedded Alley Solutions <source@embeddedalley.com>, which in turn
 * was based on skeletonfb.c, Skeleton for a frame buffer device by
 * Geert Uytterhoeven.
 */

#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/version.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
#if defined(CONFIG_OF)
#include <linux/of_device.h>
#include <linux/of_platform.h>
#endif
#include <asm/io.h>
#include <linux/xilinxfb.h>

#define DRIVER_NAME             "xilinxfb"
#define DRIVER_DESCRIPTION      "Xilinx TFT LCD frame buffer driver"

/*
 * Xilinx calls it "PLB TFT LCD Controller" though it can also be used for
 * the VGA port on the Xilinx ML40x board. This is a hardware display controller
 * for a 640x480 resolution TFT or VGA screen.
 *
 * The interface to the framebuffer is nice and simple.  There are two
 * control registers.  The first tells the LCD interface where in memory
 * the frame buffer is (only the 11 most significant bits are used, so
 * don't start thinking about scrolling).  The second allows the LCD to
 * be turned on or off as well as rotated 180 degrees.
 */
#define NUM_REGS        2
#define REG_FB_ADDR     0
#define REG_CTRL        1
#define REG_CTRL_ENABLE  0x0001
#define REG_CTRL_ROTATE  0x0002

/*
 * The hardware only handles a single mode: 640x480 24 bit true
 * color. Each pixel gets a word (32 bits) of memory.  Within each word,
 * the 8 most significant bits are ignored, the next 8 bits are the red
 * level, the next 8 bits are the green level and the 8 least
 * significant bits are the blue level.  Each row of the LCD uses 1024
 * words, but only the first 640 pixels are displayed with the other 384
 * words being ignored.  There are 480 rows.
 */
#define BYTES_PER_PIXEL 4
#define BITS_PER_PIXEL  (BYTES_PER_PIXEL * 8)

#define RED_SHIFT       16
#define GREEN_SHIFT     8
#define BLUE_SHIFT      0

#define PALETTE_ENTRIES_NO      16      /* passed to fb_alloc_cmap() */

/*
 * Default xilinxfb configuration
 */
static struct xilinxfb_platform_data xilinx_fb_default_pdata = {
        .xres = 640,
        .yres = 480,
        .xvirt = 1024,
        .yvirt = 480,
};

/*
 * Here are the default fb_fix_screeninfo and fb_var_screeninfo structures
 */
static struct fb_fix_screeninfo xilinx_fb_fix = {
        .id =           "Xilinx",
        .type =         FB_TYPE_PACKED_PIXELS,
        .visual =       FB_VISUAL_TRUECOLOR,
        .accel =        FB_ACCEL_NONE
};

static struct fb_var_screeninfo xilinx_fb_var = {
        .bits_per_pixel =       BITS_PER_PIXEL,

        .red =          { RED_SHIFT, 8, 0 },
        .green =        { GREEN_SHIFT, 8, 0 },
        .blue =         { BLUE_SHIFT, 8, 0 },
        .transp =       { 0, 0, 0 },

        .activate =     FB_ACTIVATE_NOW
};

struct xilinxfb_drvdata {

        struct fb_info  info;           /* FB driver info record */

        u32             regs_phys;      /* phys. address of the control registers */
        u32 __iomem     *regs;          /* virt. address of the control registers */

        void            *fb_virt;       /* virt. address of the frame buffer */
        dma_addr_t      fb_phys;        /* phys. address of the frame buffer */
        int             fb_alloced;     /* Flag, was the fb memory alloced? */

        u32             reg_ctrl_default;

        u32             pseudo_palette[PALETTE_ENTRIES_NO];
                                        /* Fake palette of 16 colors */
};

#define to_xilinxfb_drvdata(_info) \
        container_of(_info, struct xilinxfb_drvdata, info)

/*
 * The LCD controller has DCR interface to its registers, but all
 * the boards and configurations the driver has been tested with
 * use opb2dcr bridge. So the registers are seen as memory mapped.
 * This macro is to make it simple to add the direct DCR access
 * when it's needed.
 */
#define xilinx_fb_out_be32(driverdata, offset, val) \
        out_be32(driverdata->regs + offset, val)

static int
xilinx_fb_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue,
        unsigned transp, struct fb_info *fbi)
{
        u32 *palette = fbi->pseudo_palette;

        if (regno >= PALETTE_ENTRIES_NO)
                return -EINVAL;

        if (fbi->var.grayscale) {
                /* Convert color to grayscale.
                 * grayscale = 0.30*R + 0.59*G + 0.11*B */
                red = green = blue =
                        (red * 77 + green * 151 + blue * 28 + 127) >> 8;
        }

        /* fbi->fix.visual is always FB_VISUAL_TRUECOLOR */

        /* We only handle 8 bits of each color. */
        red >>= 8;
        green >>= 8;
        blue >>= 8;
        palette[regno] = (red << RED_SHIFT) | (green << GREEN_SHIFT) |
                         (blue << BLUE_SHIFT);

        return 0;
}

static int
xilinx_fb_blank(int blank_mode, struct fb_info *fbi)
{
        struct xilinxfb_drvdata *drvdata = to_xilinxfb_drvdata(fbi);

        switch (blank_mode) {
        case FB_BLANK_UNBLANK:
                /* turn on panel */
                xilinx_fb_out_be32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);
                break;

        case FB_BLANK_NORMAL:
        case FB_BLANK_VSYNC_SUSPEND:
        case FB_BLANK_HSYNC_SUSPEND:
        case FB_BLANK_POWERDOWN:
                /* turn off panel */
                xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
        default:
                break;

        }
        return 0; /* success */
}

static struct fb_ops xilinxfb_ops =
{
        .owner                  = THIS_MODULE,
        .fb_setcolreg           = xilinx_fb_setcolreg,
        .fb_blank               = xilinx_fb_blank,
        .fb_fillrect            = cfb_fillrect,
        .fb_copyarea            = cfb_copyarea,
        .fb_imageblit           = cfb_imageblit,
};

/* ---------------------------------------------------------------------
 * Bus independent setup/teardown
 */

static int xilinxfb_assign(struct device *dev, unsigned long physaddr,
                           struct xilinxfb_platform_data *pdata)
{
        struct xilinxfb_drvdata *drvdata;
        int rc;
        int fbsize = pdata->xvirt * pdata->yvirt * BYTES_PER_PIXEL;

        /* Allocate the driver data region */
        drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL);
        if (!drvdata) {
                dev_err(dev, "Couldn't allocate device private record\n");
                return -ENOMEM;
        }
        dev_set_drvdata(dev, drvdata);

        /* Map the control registers in */
        if (!request_mem_region(physaddr, 8, DRIVER_NAME)) {
                dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
                        physaddr);
                rc = -ENODEV;
                goto err_region;
        }
        drvdata->regs_phys = physaddr;
        drvdata->regs = ioremap(physaddr, 8);
        if (!drvdata->regs) {
                dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
                        physaddr);
                rc = -ENODEV;
                goto err_map;
        }

        /* Allocate the framebuffer memory */
        if (pdata->fb_phys) {
                drvdata->fb_phys = pdata->fb_phys;
                drvdata->fb_virt = ioremap(pdata->fb_phys, fbsize);
        } else {
                drvdata->fb_alloced = 1;
                drvdata->fb_virt = dma_alloc_coherent(dev, PAGE_ALIGN(fbsize),
                                        &drvdata->fb_phys, GFP_KERNEL);
        }

        if (!drvdata->fb_virt) {
                dev_err(dev, "Could not allocate frame buffer memory\n");
                rc = -ENOMEM;
                goto err_fbmem;
        }

        /* Clear (turn to black) the framebuffer */
        memset_io((void __iomem *)drvdata->fb_virt, 0, fbsize);

        /* Tell the hardware where the frame buffer is */
        xilinx_fb_out_be32(drvdata, REG_FB_ADDR, drvdata->fb_phys);

        /* Turn on the display */
        drvdata->reg_ctrl_default = REG_CTRL_ENABLE;
        if (pdata->rotate_screen)
                drvdata->reg_ctrl_default |= REG_CTRL_ROTATE;
        xilinx_fb_out_be32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);

        /* Fill struct fb_info */
        drvdata->info.device = dev;
        drvdata->info.screen_base = (void __iomem *)drvdata->fb_virt;
        drvdata->info.fbops = &xilinxfb_ops;
        drvdata->info.fix = xilinx_fb_fix;
        drvdata->info.fix.smem_start = drvdata->fb_phys;
        drvdata->info.fix.smem_len = fbsize;
        drvdata->info.fix.line_length = pdata->xvirt * BYTES_PER_PIXEL;

        drvdata->info.pseudo_palette = drvdata->pseudo_palette;
        drvdata->info.flags = FBINFO_DEFAULT;
        drvdata->info.var = xilinx_fb_var;
        drvdata->info.var.height = pdata->screen_height_mm;
        drvdata->info.var.width = pdata->screen_width_mm;
        drvdata->info.var.xres = pdata->xres;
        drvdata->info.var.yres = pdata->yres;
        drvdata->info.var.xres_virtual = pdata->xvirt;
        drvdata->info.var.yres_virtual = pdata->yvirt;

        /* Allocate a colour map */
        rc = fb_alloc_cmap(&drvdata->info.cmap, PALETTE_ENTRIES_NO, 0);
        if (rc) {
                dev_err(dev, "Fail to allocate colormap (%d entries)\n",
                        PALETTE_ENTRIES_NO);
                goto err_cmap;
        }

        /* Register new frame buffer */
        rc = register_framebuffer(&drvdata->info);
        if (rc) {
                dev_err(dev, "Could not register frame buffer\n");
                goto err_regfb;
        }

        /* Put a banner in the log (for DEBUG) */
        dev_dbg(dev, "regs: phys=%lx, virt=%p\n", physaddr, drvdata->regs);
        dev_dbg(dev, "fb: phys=%p, virt=%p, size=%x\n",
                (void*)drvdata->fb_phys, drvdata->fb_virt, fbsize);

        return 0;       /* success */

err_regfb:
        fb_dealloc_cmap(&drvdata->info.cmap);

err_cmap:
        if (drvdata->fb_alloced)
                dma_free_coherent(dev, PAGE_ALIGN(fbsize), drvdata->fb_virt,
                        drvdata->fb_phys);
        /* Turn off the display */
        xilinx_fb_out_be32(drvdata, REG_CTRL, 0);

err_fbmem:
        iounmap(drvdata->regs);

err_map:
        release_mem_region(physaddr, 8);

err_region:
        kfree(drvdata);
        dev_set_drvdata(dev, NULL);

        return rc;
}

static int xilinxfb_release(struct device *dev)
{
        struct xilinxfb_drvdata *drvdata = dev_get_drvdata(dev);

#if !defined(CONFIG_FRAMEBUFFER_CONSOLE) && defined(CONFIG_LOGO)
        xilinx_fb_blank(VESA_POWERDOWN, &drvdata->info);
#endif

        unregister_framebuffer(&drvdata->info);

        fb_dealloc_cmap(&drvdata->info.cmap);

        if (drvdata->fb_alloced)
                dma_free_coherent(dev, PAGE_ALIGN(drvdata->info.fix.smem_len),
                                  drvdata->fb_virt, drvdata->fb_phys);

        /* Turn off the display */
        xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
        iounmap(drvdata->regs);

        release_mem_region(drvdata->regs_phys, 8);

        kfree(drvdata);
        dev_set_drvdata(dev, NULL);

        return 0;
}

/* ---------------------------------------------------------------------
 * Platform bus binding
 */

static int
xilinxfb_platform_probe(struct platform_device *pdev)
{
        struct xilinxfb_platform_data *pdata;
        struct resource *res;

        /* Find the registers address */
        res = platform_get_resource(pdev, IORESOURCE_IO, 0);
        if (!res) {
                dev_err(&pdev->dev, "Couldn't get registers resource\n");
                return -ENODEV;
        }

        /* If a pdata structure is provided, then extract the parameters */
        pdata = &xilinx_fb_default_pdata;
        if (pdev->dev.platform_data) {
                pdata = pdev->dev.platform_data;
                if (!pdata->xres)
                        pdata->xres = xilinx_fb_default_pdata.xres;
                if (!pdata->yres)
                        pdata->yres = xilinx_fb_default_pdata.yres;
                if (!pdata->xvirt)
                        pdata->xvirt = xilinx_fb_default_pdata.xvirt;
                if (!pdata->yvirt)
                        pdata->yvirt = xilinx_fb_default_pdata.yvirt;
        }

        return xilinxfb_assign(&pdev->dev, res->start, pdata);
}

static int
xilinxfb_platform_remove(struct platform_device *pdev)
{
        return xilinxfb_release(&pdev->dev);
}


static struct platform_driver xilinxfb_platform_driver = {
        .probe          = xilinxfb_platform_probe,
        .remove         = xilinxfb_platform_remove,
        .driver = {
                .owner = THIS_MODULE,
                .name = DRIVER_NAME,
        },
};

/* ---------------------------------------------------------------------
 * OF bus binding
 */

#if defined(CONFIG_OF)
static int __devinit
xilinxfb_of_probe(struct of_device *op, const struct of_device_id *match)
{
        struct resource res;
        const u32 *prop;
        struct xilinxfb_platform_data pdata;
        int size, rc;

        /* Copy with the default pdata (not a ptr reference!) */
        pdata = xilinx_fb_default_pdata;

        dev_dbg(&op->dev, "xilinxfb_of_probe(%p, %p)\n", op, match);

        rc = of_address_to_resource(op->node, 0, &res);
        if (rc) {
                dev_err(&op->dev, "invalid address\n");
                return rc;
        }

        prop = of_get_property(op->node, "phys-size", &size);
        if ((prop) && (size >= sizeof(u32)*2)) {
                pdata.screen_width_mm = prop[0];
                pdata.screen_height_mm = prop[1];
        }

        prop = of_get_property(op->node, "resolution", &size);
        if ((prop) && (size >= sizeof(u32)*2)) {
                pdata.xres = prop[0];
                pdata.yres = prop[1];
        }

        prop = of_get_property(op->node, "virtual-resolution", &size);
        if ((prop) && (size >= sizeof(u32)*2)) {
                pdata.xvirt = prop[0];
                pdata.yvirt = prop[1];
        }

        if (of_find_property(op->node, "rotate-display", NULL))
                pdata.rotate_screen = 1;

        return xilinxfb_assign(&op->dev, res.start, &pdata);
}

static int __devexit xilinxfb_of_remove(struct of_device *op)
{
        return xilinxfb_release(&op->dev);
}

/* Match table for of_platform binding */
static struct of_device_id xilinxfb_of_match[] __devinitdata = {
        { .compatible = "xlnx,plb-tft-cntlr-ref-1.00.a", },
        {},
};
MODULE_DEVICE_TABLE(of, xilinxfb_of_match);

static struct of_platform_driver xilinxfb_of_driver = {
        .owner = THIS_MODULE,
        .name = DRIVER_NAME,
        .match_table = xilinxfb_of_match,
        .probe = xilinxfb_of_probe,
        .remove = __devexit_p(xilinxfb_of_remove),
        .driver = {
                .name = DRIVER_NAME,
        },
};

/* Registration helpers to keep the number of #ifdefs to a minimum */
static inline int __init xilinxfb_of_register(void)
{
        pr_debug("xilinxfb: calling of_register_platform_driver()\n");
        return of_register_platform_driver(&xilinxfb_of_driver);
}

static inline void __exit xilinxfb_of_unregister(void)
{
        of_unregister_platform_driver(&xilinxfb_of_driver);
}
#else /* CONFIG_OF */
/* CONFIG_OF not enabled; do nothing helpers */
static inline int __init xilinxfb_of_register(void) { return 0; }
static inline void __exit xilinxfb_of_unregister(void) { }
#endif /* CONFIG_OF */

/* ---------------------------------------------------------------------
 * Module setup and teardown
 */

static int __init
xilinxfb_init(void)
{
        int rc;
        rc = xilinxfb_of_register();
        if (rc)
                return rc;

        rc = platform_driver_register(&xilinxfb_platform_driver);
        if (rc)
                xilinxfb_of_unregister();

        return rc;
}

static void __exit
xilinxfb_cleanup(void)
{
        platform_driver_unregister(&xilinxfb_platform_driver);
        xilinxfb_of_unregister();
}

module_init(xilinxfb_init);
module_exit(xilinxfb_cleanup);

MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>");
MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
MODULE_LICENSE("GPL");