atmel_lcdfb.c

来自「linux 内核源代码」· C语言 代码 · 共 806 行 · 第 1/2 页

 *      @red: The red value which can be up to 16 bits wide
 *	@green: The green value which can be up to 16 bits wide
 *	@blue:  The blue value which can be up to 16 bits wide.
 *	@transp: If supported the alpha value which can be up to 16 bits wide.
 *      @info: frame buffer info structure
 *
 *  	Set a single color register. The values supplied have a 16 bit
 *  	magnitude which needs to be scaled in this function for the hardware.
 *	Things to take into consideration are how many color registers, if
 *	any, are supported with the current color visual. With truecolor mode
 *	no color palettes are supported. Here a psuedo palette is created
 *	which we store the value in pseudo_palette in struct fb_info. For
 *	pseudocolor mode we have a limited color palette. To deal with this
 *	we can program what color is displayed for a particular pixel value.
 *	DirectColor is similar in that we can program each color field. If
 *	we have a static colormap we don't need to implement this function.
 *
 *	Returns negative errno on error, or zero on success. In an
 *	ideal world, this would have been the case, but as it turns
 *	out, the other drivers return 1 on failure, so that's what
 *	we're going to do.
 */
static int atmel_lcdfb_setcolreg(unsigned int regno, unsigned int red,
			     unsigned int green, unsigned int blue,
			     unsigned int transp, struct fb_info *info)
{
	struct atmel_lcdfb_info *sinfo = info->par;
	unsigned int val;
	u32 *pal;
	int ret = 1;

	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) {
			pal = info->pseudo_palette;

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

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

	case FB_VISUAL_PSEUDOCOLOR:
		if (regno < 256) {
			val  = ((red   >> 11) & 0x001f);
			val |= ((green >>  6) & 0x03e0);
			val |= ((blue  >>  1) & 0x7c00);

			/*
			 * TODO: intensity bit. Maybe something like
			 *   ~(red[10] ^ green[10] ^ blue[10]) & 1
			 */

			lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
			ret = 0;
		}
		break;

	case FB_VISUAL_MONO01:
		if (regno < 2) {
			val = (regno == 0) ? 0x00 : 0x1F;
			lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
			ret = 0;
		}
		break;

	}

	return ret;
}

static int atmel_lcdfb_pan_display(struct fb_var_screeninfo *var,
			       struct fb_info *info)
{
	dev_dbg(info->device, "%s\n", __func__);

	atmel_lcdfb_update_dma(info, var);

	return 0;
}

static struct fb_ops atmel_lcdfb_ops = {
	.owner		= THIS_MODULE,
	.fb_check_var	= atmel_lcdfb_check_var,
	.fb_set_par	= atmel_lcdfb_set_par,
	.fb_setcolreg	= atmel_lcdfb_setcolreg,
	.fb_pan_display	= atmel_lcdfb_pan_display,
	.fb_fillrect	= cfb_fillrect,
	.fb_copyarea	= cfb_copyarea,
	.fb_imageblit	= cfb_imageblit,
};

static irqreturn_t atmel_lcdfb_interrupt(int irq, void *dev_id)
{
	struct fb_info *info = dev_id;
	struct atmel_lcdfb_info *sinfo = info->par;
	u32 status;

	status = lcdc_readl(sinfo, ATMEL_LCDC_ISR);
	lcdc_writel(sinfo, ATMEL_LCDC_IDR, status);
	return IRQ_HANDLED;
}

static int __init atmel_lcdfb_init_fbinfo(struct atmel_lcdfb_info *sinfo)
{
	struct fb_info *info = sinfo->info;
	int ret = 0;

	memset_io(info->screen_base, 0, info->fix.smem_len);
	info->var.activate |= FB_ACTIVATE_FORCE | FB_ACTIVATE_NOW;

	dev_info(info->device,
	       "%luKiB frame buffer at %08lx (mapped at %p)\n",
	       (unsigned long)info->fix.smem_len / 1024,
	       (unsigned long)info->fix.smem_start,
	       info->screen_base);

	/* Allocate colormap */
	ret = fb_alloc_cmap(&info->cmap, 256, 0);
	if (ret < 0)
		dev_err(info->device, "Alloc color map failed\n");

	return ret;
}

static void atmel_lcdfb_start_clock(struct atmel_lcdfb_info *sinfo)
{
	if (sinfo->bus_clk)
		clk_enable(sinfo->bus_clk);
	clk_enable(sinfo->lcdc_clk);
}

static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
{
	if (sinfo->bus_clk)
		clk_disable(sinfo->bus_clk);
	clk_disable(sinfo->lcdc_clk);
}


static int __init atmel_lcdfb_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct fb_info *info;
	struct atmel_lcdfb_info *sinfo;
	struct atmel_lcdfb_info *pdata_sinfo;
	struct resource *regs = NULL;
	struct resource *map = NULL;
	int ret;

	dev_dbg(dev, "%s BEGIN\n", __func__);

	ret = -ENOMEM;
	info = framebuffer_alloc(sizeof(struct atmel_lcdfb_info), dev);
	if (!info) {
		dev_err(dev, "cannot allocate memory\n");
		goto out;
	}

	sinfo = info->par;

	if (dev->platform_data) {
		pdata_sinfo = (struct atmel_lcdfb_info *)dev->platform_data;
		sinfo->default_bpp = pdata_sinfo->default_bpp;
		sinfo->default_dmacon = pdata_sinfo->default_dmacon;
		sinfo->default_lcdcon2 = pdata_sinfo->default_lcdcon2;
		sinfo->default_monspecs = pdata_sinfo->default_monspecs;
		sinfo->atmel_lcdfb_power_control = pdata_sinfo->atmel_lcdfb_power_control;
		sinfo->guard_time = pdata_sinfo->guard_time;
	} else {
		dev_err(dev, "cannot get default configuration\n");
		goto free_info;
	}
	sinfo->info = info;
	sinfo->pdev = pdev;

	strcpy(info->fix.id, sinfo->pdev->name);
	info->flags = ATMEL_LCDFB_FBINFO_DEFAULT;
	info->pseudo_palette = sinfo->pseudo_palette;
	info->fbops = &atmel_lcdfb_ops;

	memcpy(&info->monspecs, sinfo->default_monspecs, sizeof(info->monspecs));
	info->fix = atmel_lcdfb_fix;

	/* Enable LCDC Clocks */
	if (cpu_is_at91sam9261() || cpu_is_at32ap7000()) {
		sinfo->bus_clk = clk_get(dev, "hck1");
		if (IS_ERR(sinfo->bus_clk)) {
			ret = PTR_ERR(sinfo->bus_clk);
			goto free_info;
		}
	}
	sinfo->lcdc_clk = clk_get(dev, "lcdc_clk");
	if (IS_ERR(sinfo->lcdc_clk)) {
		ret = PTR_ERR(sinfo->lcdc_clk);
		goto put_bus_clk;
	}
	atmel_lcdfb_start_clock(sinfo);

	ret = fb_find_mode(&info->var, info, NULL, info->monspecs.modedb,
			info->monspecs.modedb_len, info->monspecs.modedb,
			sinfo->default_bpp);
	if (!ret) {
		dev_err(dev, "no suitable video mode found\n");
		goto stop_clk;
	}


	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!regs) {
		dev_err(dev, "resources unusable\n");
		ret = -ENXIO;
		goto stop_clk;
	}

	sinfo->irq_base = platform_get_irq(pdev, 0);
	if (sinfo->irq_base < 0) {
		dev_err(dev, "unable to get irq\n");
		ret = sinfo->irq_base;
		goto stop_clk;
	}

	/* Initialize video memory */
	map = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	if (map) {
		/* use a pre-allocated memory buffer */
		info->fix.smem_start = map->start;
		info->fix.smem_len = map->end - map->start + 1;
		if (!request_mem_region(info->fix.smem_start,
					info->fix.smem_len, pdev->name)) {
			ret = -EBUSY;
			goto stop_clk;
		}

		info->screen_base = ioremap(info->fix.smem_start, info->fix.smem_len);
		if (!info->screen_base)
			goto release_intmem;
	} else {
		/* alocate memory buffer */
		ret = atmel_lcdfb_alloc_video_memory(sinfo);
		if (ret < 0) {
			dev_err(dev, "cannot allocate framebuffer: %d\n", ret);
			goto stop_clk;
		}
	}

	/* LCDC registers */
	info->fix.mmio_start = regs->start;
	info->fix.mmio_len = regs->end - regs->start + 1;

	if (!request_mem_region(info->fix.mmio_start,
				info->fix.mmio_len, pdev->name)) {
		ret = -EBUSY;
		goto free_fb;
	}

	sinfo->mmio = ioremap(info->fix.mmio_start, info->fix.mmio_len);
	if (!sinfo->mmio) {
		dev_err(dev, "cannot map LCDC registers\n");
		goto release_mem;
	}

	/* interrupt */
	ret = request_irq(sinfo->irq_base, atmel_lcdfb_interrupt, 0, pdev->name, info);
	if (ret) {
		dev_err(dev, "request_irq failed: %d\n", ret);
		goto unmap_mmio;
	}

	ret = atmel_lcdfb_init_fbinfo(sinfo);
	if (ret < 0) {
		dev_err(dev, "init fbinfo failed: %d\n", ret);
		goto unregister_irqs;
	}

	/*
	 * This makes sure that our colour bitfield
	 * descriptors are correctly initialised.
	 */
	atmel_lcdfb_check_var(&info->var, info);

	ret = fb_set_var(info, &info->var);
	if (ret) {
		dev_warn(dev, "unable to set display parameters\n");
		goto free_cmap;
	}

	dev_set_drvdata(dev, info);

	/*
	 * Tell the world that we're ready to go
	 */
	ret = register_framebuffer(info);
	if (ret < 0) {
		dev_err(dev, "failed to register framebuffer device: %d\n", ret);
		goto free_cmap;
	}

	/* Power up the LCDC screen */
	if (sinfo->atmel_lcdfb_power_control)
		sinfo->atmel_lcdfb_power_control(1);

	dev_info(dev, "fb%d: Atmel LCDC at 0x%08lx (mapped at %p), irq %lu\n",
		       info->node, info->fix.mmio_start, sinfo->mmio, sinfo->irq_base);

	return 0;


free_cmap:
	fb_dealloc_cmap(&info->cmap);
unregister_irqs:
	free_irq(sinfo->irq_base, info);
unmap_mmio:
	iounmap(sinfo->mmio);
release_mem:
 	release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
free_fb:
	if (map)
		iounmap(info->screen_base);
	else
		atmel_lcdfb_free_video_memory(sinfo);

release_intmem:
	if (map)
		release_mem_region(info->fix.smem_start, info->fix.smem_len);
stop_clk:
	atmel_lcdfb_stop_clock(sinfo);
	clk_put(sinfo->lcdc_clk);
put_bus_clk:
	if (sinfo->bus_clk)
		clk_put(sinfo->bus_clk);
free_info:
	framebuffer_release(info);
out:
	dev_dbg(dev, "%s FAILED\n", __func__);
	return ret;
}

static int __exit atmel_lcdfb_remove(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct fb_info *info = dev_get_drvdata(dev);
	struct atmel_lcdfb_info *sinfo = info->par;

	if (!sinfo)
		return 0;

	if (sinfo->atmel_lcdfb_power_control)
		sinfo->atmel_lcdfb_power_control(0);
	unregister_framebuffer(info);
	atmel_lcdfb_stop_clock(sinfo);
	clk_put(sinfo->lcdc_clk);
	if (sinfo->bus_clk)
		clk_put(sinfo->bus_clk);
	fb_dealloc_cmap(&info->cmap);
	free_irq(sinfo->irq_base, info);
	iounmap(sinfo->mmio);
 	release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
	if (platform_get_resource(pdev, IORESOURCE_MEM, 1)) {
		iounmap(info->screen_base);
		release_mem_region(info->fix.smem_start, info->fix.smem_len);
	} else {
		atmel_lcdfb_free_video_memory(sinfo);
	}

	dev_set_drvdata(dev, NULL);
	framebuffer_release(info);

	return 0;
}

static struct platform_driver atmel_lcdfb_driver = {
	.remove		= __exit_p(atmel_lcdfb_remove),
	.driver		= {
		.name	= "atmel_lcdfb",
		.owner	= THIS_MODULE,
	},
};

static int __init atmel_lcdfb_init(void)
{
	return platform_driver_probe(&atmel_lcdfb_driver, atmel_lcdfb_probe);
}

static void __exit atmel_lcdfb_exit(void)
{
	platform_driver_unregister(&atmel_lcdfb_driver);
}

module_init(atmel_lcdfb_init);
module_exit(atmel_lcdfb_exit);

MODULE_DESCRIPTION("AT91/AT32 LCD Controller framebuffer driver");
MODULE_AUTHOR("Nicolas Ferre <[e-mail]>");
MODULE_LICENSE("GPL");