/*
   * SH7760/SH7763 LCDC Framebuffer driver.
   *
   * (c) 2006-2008 MSC Vertriebsges.m.b.H.,
   *             Manuel Lauss <mano@roarinelk.homelinux.net>
   * (c) 2008 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.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.
   *
   * PLEASE HAVE A LOOK AT Documentation/fb/sh7760fb.txt!
   *
   * Thanks to Siegfried Schaefer <s.schaefer at schaefer-edv.de>
   *     for his original source and testing!

   *
   * sh7760_setcolreg get from drivers/video/sh_mobile_lcdcfb.c

   */
  
  #include <linux/completion.h>
  #include <linux/delay.h>
  #include <linux/dma-mapping.h>
  #include <linux/fb.h>
  #include <linux/interrupt.h>
  #include <linux/io.h>
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/platform_device.h>

  #include <linux/slab.h>

  
  #include <asm/sh7760fb.h>
  
  struct sh7760fb_par {
  	void __iomem *base;
  	int irq;
  
  	struct sh7760fb_platdata *pd;	/* display information */
  
  	dma_addr_t fbdma;	/* physical address */
  
  	int rot;		/* rotation enabled? */
  
  	u32 pseudo_palette[16];
  
  	struct platform_device *dev;
  	struct resource *ioarea;
  	struct completion vsync;	/* vsync irq event */
  };
  
  static irqreturn_t sh7760fb_irq(int irq, void *data)
  {
  	struct completion *c = data;
  
  	complete(c);
  
  	return IRQ_HANDLED;
  }

  /* wait_for_lps - wait until power supply has reached a certain state. */
  static int wait_for_lps(struct sh7760fb_par *par, int val)
  {
  	int i = 100;
  	while (--i && ((ioread16(par->base + LDPMMR) & 3) != val))
  		msleep(1);
  
  	if (i <= 0)
  		return -ETIMEDOUT;
  
  	return 0;
  }
  
  /* en/disable the LCDC */
  static int sh7760fb_blank(int blank, struct fb_info *info)
  {
  	struct sh7760fb_par *par = info->par;
  	struct sh7760fb_platdata *pd = par->pd;
  	unsigned short cntr = ioread16(par->base + LDCNTR);
  	unsigned short intr = ioread16(par->base + LDINTR);
  	int lps;
  
  	if (blank == FB_BLANK_UNBLANK) {
  		intr |= VINT_START;
  		cntr = LDCNTR_DON2 | LDCNTR_DON;
  		lps = 3;
  	} else {
  		intr &= ~VINT_START;
  		cntr = LDCNTR_DON2;
  		lps = 0;
  	}
  
  	if (pd->blank)
  		pd->blank(blank);
  
  	iowrite16(intr, par->base + LDINTR);
  	iowrite16(cntr, par->base + LDCNTR);
  
  	return wait_for_lps(par, lps);
  }

  static int sh7760_setcolreg (u_int regno,
  	u_int red, u_int green, u_int blue,
  	u_int transp, struct fb_info *info)

  {

  	u32 *palette = info->pseudo_palette;

  	if (regno >= 16)
  		return -EINVAL;
  
  	/* only FB_VISUAL_TRUECOLOR supported */
  
  	red >>= 16 - info->var.red.length;
  	green >>= 16 - info->var.green.length;
  	blue >>= 16 - info->var.blue.length;
  	transp >>= 16 - info->var.transp.length;
  
  	palette[regno] = (red << info->var.red.offset) |
  		(green << info->var.green.offset) |
  		(blue << info->var.blue.offset) |
  		(transp << info->var.transp.offset);
  
  	return 0;

  }

  static int sh7760fb_get_color_info(struct device *dev,
  				   u16 lddfr, int *bpp, int *gray)
  {
  	int lbpp, lgray;
  
  	lgray = lbpp = 0;
  
  	switch (lddfr & LDDFR_COLOR_MASK) {
  	case LDDFR_1BPP_MONO:
  		lgray = 1;
  		lbpp = 1;
  		break;
  	case LDDFR_2BPP_MONO:
  		lgray = 1;
  		lbpp = 2;
  		break;
  	case LDDFR_4BPP_MONO:
  		lgray = 1;
  	case LDDFR_4BPP:
  		lbpp = 4;
  		break;
  	case LDDFR_6BPP_MONO:
  		lgray = 1;
  	case LDDFR_8BPP:
  		lbpp = 8;
  		break;
  	case LDDFR_16BPP_RGB555:
  	case LDDFR_16BPP_RGB565:
  		lbpp = 16;
  		lgray = 0;
  		break;
  	default:
  		dev_dbg(dev, "unsupported LDDFR bit depth.
  ");
  		return -EINVAL;
  	}
  
  	if (bpp)
  		*bpp = lbpp;
  	if (gray)
  		*gray = lgray;
  
  	return 0;
  }
  
  static int sh7760fb_check_var(struct fb_var_screeninfo *var,
  			      struct fb_info *info)
  {
  	struct fb_fix_screeninfo *fix = &info->fix;
  	struct sh7760fb_par *par = info->par;
  	int ret, bpp;
  
  	/* get color info from register value */
  	ret = sh7760fb_get_color_info(info->dev, par->pd->lddfr, &bpp, NULL);
  	if (ret)
  		return ret;
  
  	var->bits_per_pixel = bpp;
  
  	if ((var->grayscale) && (var->bits_per_pixel == 1))
  		fix->visual = FB_VISUAL_MONO10;
  	else if (var->bits_per_pixel >= 15)
  		fix->visual = FB_VISUAL_TRUECOLOR;
  	else
  		fix->visual = FB_VISUAL_PSEUDOCOLOR;
  
  	/* TODO: add some more validation here */
  	return 0;
  }
  
  /*
   * sh7760fb_set_par - set videomode.
   *
   * NOTE: The rotation, grayscale and DSTN codepaths are
   *     totally untested!
   */
  static int sh7760fb_set_par(struct fb_info *info)
  {
  	struct sh7760fb_par *par = info->par;
  	struct fb_videomode *vm = par->pd->def_mode;
  	unsigned long sbase, dstn_off, ldsarl, stride;
  	unsigned short hsynp, hsynw, htcn, hdcn;
  	unsigned short vsynp, vsynw, vtln, vdln;
  	unsigned short lddfr, ldmtr;
  	int ret, bpp, gray;
  
  	par->rot = par->pd->rotate;
  
  	/* rotate only works with xres <= 320 */
  	if (par->rot && (vm->xres > 320)) {
  		dev_dbg(info->dev, "rotation disabled due to display size
  ");
  		par->rot = 0;
  	}
  
  	/* calculate LCDC reg vals from display parameters */
  	hsynp = vm->right_margin + vm->xres;
  	hsynw = vm->hsync_len;
  	htcn = vm->left_margin + hsynp + hsynw;
  	hdcn = vm->xres;
  	vsynp = vm->lower_margin + vm->yres;
  	vsynw = vm->vsync_len;
  	vtln = vm->upper_margin + vsynp + vsynw;
  	vdln = vm->yres;
  
  	/* get color info from register value */
  	ret = sh7760fb_get_color_info(info->dev, par->pd->lddfr, &bpp, &gray);
  	if (ret)
  		return ret;
  
  	dev_dbg(info->dev, "%dx%d %dbpp %s (orientation %s)
  ", hdcn,
  		vdln, bpp, gray ? "grayscale" : "color",
  		par->rot ? "rotated" : "normal");
  
  #ifdef CONFIG_CPU_LITTLE_ENDIAN
  	lddfr = par->pd->lddfr | (1 << 8);
  #else
  	lddfr = par->pd->lddfr & ~(1 << 8);
  #endif
  
  	ldmtr = par->pd->ldmtr;
  
  	if (!(vm->sync & FB_SYNC_HOR_HIGH_ACT))
  		ldmtr |= LDMTR_CL1POL;
  	if (!(vm->sync & FB_SYNC_VERT_HIGH_ACT))
  		ldmtr |= LDMTR_FLMPOL;
  
  	/* shut down LCDC before changing display parameters */
  	sh7760fb_blank(FB_BLANK_POWERDOWN, info);
  
  	iowrite16(par->pd->ldickr, par->base + LDICKR);	/* pixclock */
  	iowrite16(ldmtr, par->base + LDMTR);	/* polarities */
  	iowrite16(lddfr, par->base + LDDFR);	/* color/depth */
  	iowrite16((par->rot ? 1 << 13 : 0), par->base + LDSMR);	/* rotate */
  	iowrite16(par->pd->ldpmmr, par->base + LDPMMR);	/* Power Management */
  	iowrite16(par->pd->ldpspr, par->base + LDPSPR);	/* Power Supply Ctrl */
  
  	/* display resolution */
  	iowrite16(((htcn >> 3) - 1) | (((hdcn >> 3) - 1) << 8),
  		  par->base + LDHCNR);
  	iowrite16(vdln - 1, par->base + LDVDLNR);
  	iowrite16(vtln - 1, par->base + LDVTLNR);
  	/* h/v sync signals */
  	iowrite16((vsynp - 1) | ((vsynw - 1) << 12), par->base + LDVSYNR);
  	iowrite16(((hsynp >> 3) - 1) | (((hsynw >> 3) - 1) << 12),
  		  par->base + LDHSYNR);
  	/* AC modulation sig */
  	iowrite16(par->pd->ldaclnr, par->base + LDACLNR);
  
  	stride = (par->rot) ? vtln : hdcn;
  	if (!gray)
  		stride *= (bpp + 7) >> 3;
  	else {
  		if (bpp == 1)
  			stride >>= 3;
  		else if (bpp == 2)
  			stride >>= 2;
  		else if (bpp == 4)
  			stride >>= 1;
  		/* 6 bpp == 8 bpp */
  	}
  
  	/* if rotated, stride must be power of 2 */
  	if (par->rot) {
  		unsigned long bit = 1 << 31;
  		while (bit) {
  			if (stride & bit)
  				break;
  			bit >>= 1;
  		}
  		if (stride & ~bit)
  			stride = bit << 1;	/* not P-o-2, round up */
  	}
  	iowrite16(stride, par->base + LDLAOR);
  
  	/* set display mem start address */
  	sbase = (unsigned long)par->fbdma;
  	if (par->rot)
  		sbase += (hdcn - 1) * stride;
  
  	iowrite32(sbase, par->base + LDSARU);
  
  	/*
  	 * for DSTN need to set address for lower half.
  	 * I (mlau) don't know which address to set it to,
  	 * so I guessed at (stride * yres/2).
  	 */
  	if (((ldmtr & 0x003f) >= LDMTR_DSTN_MONO_8) &&
  	    ((ldmtr & 0x003f) <= LDMTR_DSTN_COLOR_16)) {
  
  		dev_dbg(info->dev, " ***** DSTN untested! *****
  ");
  
  		dstn_off = stride;
  		if (par->rot)
  			dstn_off *= hdcn >> 1;
  		else
  			dstn_off *= vdln >> 1;
  
  		ldsarl = sbase + dstn_off;
  	} else
  		ldsarl = 0;
  
  	iowrite32(ldsarl, par->base + LDSARL);	/* mem for lower half of DSTN */

  	info->fix.line_length = stride;

  	sh7760fb_check_var(&info->var, info);
  
  	sh7760fb_blank(FB_BLANK_UNBLANK, info);	/* panel on! */
  
  	dev_dbg(info->dev, "hdcn  : %6d htcn  : %6d
  ", hdcn, htcn);
  	dev_dbg(info->dev, "hsynw : %6d hsynp : %6d
  ", hsynw, hsynp);
  	dev_dbg(info->dev, "vdln  : %6d vtln  : %6d
  ", vdln, vtln);
  	dev_dbg(info->dev, "vsynw : %6d vsynp : %6d
  ", vsynw, vsynp);
  	dev_dbg(info->dev, "clksrc: %6d clkdiv: %6d
  ",
  		(par->pd->ldickr >> 12) & 3, par->pd->ldickr & 0x1f);
  	dev_dbg(info->dev, "ldpmmr: 0x%04x ldpspr: 0x%04x
  ", par->pd->ldpmmr,
  		par->pd->ldpspr);
  	dev_dbg(info->dev, "ldmtr : 0x%04x lddfr : 0x%04x
  ", ldmtr, lddfr);
  	dev_dbg(info->dev, "ldlaor: %ld
  ", stride);
  	dev_dbg(info->dev, "ldsaru: 0x%08lx ldsarl: 0x%08lx
  ", sbase, ldsarl);
  
  	return 0;
  }
  
  static struct fb_ops sh7760fb_ops = {
  	.owner = THIS_MODULE,
  	.fb_blank = sh7760fb_blank,
  	.fb_check_var = sh7760fb_check_var,

  	.fb_setcolreg = sh7760_setcolreg,

  	.fb_set_par = sh7760fb_set_par,
  	.fb_fillrect = cfb_fillrect,
  	.fb_copyarea = cfb_copyarea,
  	.fb_imageblit = cfb_imageblit,
  };
  
  static void sh7760fb_free_mem(struct fb_info *info)
  {
  	struct sh7760fb_par *par = info->par;
  
  	if (!info->screen_base)
  		return;
  
  	dma_free_coherent(info->dev, info->screen_size,
  			  info->screen_base, par->fbdma);
  
  	par->fbdma = 0;
  	info->screen_base = NULL;
  	info->screen_size = 0;
  }
  
  /* allocate the framebuffer memory. This memory must be in Area3,
   * (dictated by the DMA engine) and contiguous, at a 512 byte boundary.
   */
  static int sh7760fb_alloc_mem(struct fb_info *info)
  {
  	struct sh7760fb_par *par = info->par;
  	void *fbmem;
  	unsigned long vram;
  	int ret, bpp;
  
  	if (info->screen_base)
  		return 0;
  
  	/* get color info from register value */
  	ret = sh7760fb_get_color_info(info->dev, par->pd->lddfr, &bpp, NULL);
  	if (ret) {
  		printk(KERN_ERR "colinfo
  ");
  		return ret;
  	}
  
  	/* min VRAM: xres_min = 16, yres_min = 1, bpp = 1: 2byte -> 1 page
  	   max VRAM: xres_max = 1024, yres_max = 1024, bpp = 16: 2MB */
  
  	vram = info->var.xres * info->var.yres;
  	if (info->var.grayscale) {
  		if (bpp == 1)
  			vram >>= 3;
  		else if (bpp == 2)
  			vram >>= 2;
  		else if (bpp == 4)
  			vram >>= 1;
  	} else if (bpp > 8)
  		vram *= 2;
  	if ((vram < 1) || (vram > 1024 * 2048)) {
  		dev_dbg(info->dev, "too much VRAM required. Check settings
  ");
  		return -ENODEV;
  	}
  
  	if (vram < PAGE_SIZE)
  		vram = PAGE_SIZE;
  
  	fbmem = dma_alloc_coherent(info->dev, vram, &par->fbdma, GFP_KERNEL);
  
  	if (!fbmem)
  		return -ENOMEM;
  
  	if ((par->fbdma & SH7760FB_DMA_MASK) != SH7760FB_DMA_MASK) {
  		sh7760fb_free_mem(info);
  		dev_err(info->dev, "kernel gave me memory at 0x%08lx, which is"
  			"unusable for the LCDC
  ", (unsigned long)par->fbdma);
  		return -ENOMEM;
  	}
  
  	info->screen_base = fbmem;
  	info->screen_size = vram;

  	info->fix.smem_start = (unsigned long)info->screen_base;
  	info->fix.smem_len = info->screen_size;

  
  	return 0;
  }

  static int sh7760fb_probe(struct platform_device *pdev)

  {
  	struct fb_info *info;
  	struct resource *res;
  	struct sh7760fb_par *par;
  	int ret;
  
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (unlikely(res == NULL)) {
  		dev_err(&pdev->dev, "invalid resource
  ");
  		return -EINVAL;
  	}
  
  	info = framebuffer_alloc(sizeof(struct sh7760fb_par), &pdev->dev);
  	if (!info)
  		return -ENOMEM;
  
  	par = info->par;
  	par->dev = pdev;
  
  	par->pd = pdev->dev.platform_data;
  	if (!par->pd) {
  		dev_dbg(info->dev, "no display setup data!
  ");
  		ret = -ENODEV;
  		goto out_fb;
  	}
  
  	par->ioarea = request_mem_region(res->start,

  					 resource_size(res), pdev->name);

  	if (!par->ioarea) {
  		dev_err(&pdev->dev, "mmio area busy
  ");
  		ret = -EBUSY;
  		goto out_fb;
  	}

  	par->base = ioremap_nocache(res->start, resource_size(res));

  	if (!par->base) {
  		dev_err(&pdev->dev, "cannot remap
  ");
  		ret = -ENODEV;
  		goto out_res;
  	}
  
  	iowrite16(0, par->base + LDINTR);	/* disable vsync irq */
  	par->irq = platform_get_irq(pdev, 0);
  	if (par->irq >= 0) {
  		ret = request_irq(par->irq, sh7760fb_irq, 0,
  				  "sh7760-lcdc", &par->vsync);
  		if (ret) {
  			dev_err(&pdev->dev, "cannot grab IRQ
  ");
  			par->irq = -ENXIO;
  		} else
  			disable_irq_nosync(par->irq);
  	}
  
  	fb_videomode_to_var(&info->var, par->pd->def_mode);
  
  	ret = sh7760fb_alloc_mem(info);
  	if (ret) {
  		dev_dbg(info->dev, "framebuffer memory allocation failed!
  ");
  		goto out_unmap;
  	}
  
  	info->pseudo_palette = par->pseudo_palette;
  
  	/* fixup color register bitpositions. These are fixed by hardware */
  	info->var.red.offset = 11;
  	info->var.red.length = 5;
  	info->var.red.msb_right = 0;
  
  	info->var.green.offset = 5;
  	info->var.green.length = 6;
  	info->var.green.msb_right = 0;
  
  	info->var.blue.offset = 0;
  	info->var.blue.length = 5;
  	info->var.blue.msb_right = 0;
  
  	info->var.transp.offset = 0;
  	info->var.transp.length = 0;
  	info->var.transp.msb_right = 0;

  	strcpy(info->fix.id, "sh7760-lcdc");

  	/* set the DON2 bit now, before cmap allocation, as it will randomize
  	 * palette memory.
  	 */
  	iowrite16(LDCNTR_DON2, par->base + LDCNTR);
  	info->fbops = &sh7760fb_ops;
  
  	ret = fb_alloc_cmap(&info->cmap, 256, 0);
  	if (ret) {
  		dev_dbg(info->dev, "Unable to allocate cmap memory
  ");
  		goto out_mem;
  	}
  
  	ret = register_framebuffer(info);
  	if (ret < 0) {
  		dev_dbg(info->dev, "cannot register fb!
  ");
  		goto out_cmap;
  	}
  	platform_set_drvdata(pdev, info);
  
  	printk(KERN_INFO "%s: memory at phys 0x%08lx-0x%08lx, size %ld KiB
  ",
  	       pdev->name,
  	       (unsigned long)par->fbdma,
  	       (unsigned long)(par->fbdma + info->screen_size - 1),
  	       info->screen_size >> 10);
  
  	return 0;
  
  out_cmap:
  	sh7760fb_blank(FB_BLANK_POWERDOWN, info);
  	fb_dealloc_cmap(&info->cmap);
  out_mem:
  	sh7760fb_free_mem(info);
  out_unmap:
  	if (par->irq >= 0)
  		free_irq(par->irq, &par->vsync);
  	iounmap(par->base);
  out_res:

  	release_mem_region(res->start, resource_size(res));

  out_fb:
  	framebuffer_release(info);
  	return ret;
  }

  static int sh7760fb_remove(struct platform_device *dev)

  {
  	struct fb_info *info = platform_get_drvdata(dev);
  	struct sh7760fb_par *par = info->par;
  
  	sh7760fb_blank(FB_BLANK_POWERDOWN, info);
  	unregister_framebuffer(info);
  	fb_dealloc_cmap(&info->cmap);
  	sh7760fb_free_mem(info);
  	if (par->irq >= 0)
  		free_irq(par->irq, par);
  	iounmap(par->base);

  	release_mem_region(par->ioarea->start, resource_size(par->ioarea));

  	framebuffer_release(info);
  	platform_set_drvdata(dev, NULL);
  
  	return 0;
  }
  
  static struct platform_driver sh7760_lcdc_driver = {
  	.driver = {
  		   .name = "sh7760-lcdc",
  		   .owner = THIS_MODULE,
  		   },
  	.probe = sh7760fb_probe,

  	.remove = sh7760fb_remove,

  };

  module_platform_driver(sh7760_lcdc_driver);

  
  MODULE_AUTHOR("Nobuhiro Iwamatsu, Manuel Lauss");
  MODULE_DESCRIPTION("FBdev for SH7760/63 integrated LCD Controller");
  MODULE_LICENSE("GPL");