skeletonfb.c

Linux环境下视频显示卡设备的驱动程序源代码

	    /* goto error path */
    }

    par = info->par;

    /* 
     * Here we set the screen_base to the virtual memory address
     * for the framebuffer. Usually we obtain the resource address
     * from the bus layer and then translate it to virtual memory
     * space via ioremap. Consult ioport.h. 
     */
    info->screen_base = framebuffer_virtual_memory;
    info->fbops = &xxxfb_ops;
    info->fix = xxxfb_fix; /* this will be the only time xxxfb_fix will be
			    * used, so mark it as __devinitdata
			    */
    info->pseudo_palette = pseudo_palette; /* The pseudopalette is an
					    * 16-member array
					    */
    /*
     * Set up flags to indicate what sort of acceleration your
     * driver can provide (pan/wrap/copyarea/etc.) and whether it
     * is a module -- see FBINFO_* in include/linux/fb.h
     *
     * If your hardware can support any of the hardware accelerated functions
     * fbcon performance will improve if info->flags is set properly.
     *
     * FBINFO_HWACCEL_COPYAREA - hardware moves
     * FBINFO_HWACCEL_FILLRECT - hardware fills
     * FBINFO_HWACCEL_IMAGEBLIT - hardware mono->color expansion
     * FBINFO_HWACCEL_YPAN - hardware can pan display in y-axis
     * FBINFO_HWACCEL_YWRAP - hardware can wrap display in y-axis
     * FBINFO_HWACCEL_DISABLED - supports hardware accels, but disabled
     * FBINFO_READS_FAST - if set, prefer moves over mono->color expansion
     * FBINFO_MISC_TILEBLITTING - hardware can do tile blits
     *
     * NOTE: These are for fbcon use only.
     */
    info->flags = FBINFO_DEFAULT;

/********************* This stage is optional ******************************/
     /*
     * The struct pixmap is a scratch pad for the drawing functions. This
     * is where the monochrome bitmap is constructed by the higher layers
     * and then passed to the accelerator.  For drivers that uses
     * cfb_imageblit, you can skip this part.  For those that have a more
     * rigorous requirement, this stage is needed
     */

    /* PIXMAP_SIZE should be small enough to optimize drawing, but not
     * large enough that memory is wasted.  A safe size is
     * (max_xres * max_font_height/8). max_xres is driver dependent,
     * max_font_height is 32.
     */
    info->pixmap.addr = kmalloc(PIXMAP_SIZE, GFP_KERNEL);
    if (!info->pixmap.addr) {
	    /* goto error */
    }

    info->pixmap.size = PIXMAP_SIZE;

    /*
     * FB_PIXMAP_SYSTEM - memory is in system ram
     * FB_PIXMAP_IO     - memory is iomapped
     * FB_PIXMAP_SYNC   - if set, will call fb_sync() per access to pixmap,
     *                    usually if FB_PIXMAP_IO is set.
     *
     * Currently, FB_PIXMAP_IO is unimplemented.
     */
    info->pixmap.flags = FB_PIXMAP_SYSTEM;

    /*
     * scan_align is the number of padding for each scanline.  It is in bytes.
     * Thus for accelerators that need padding to the next u32, put 4 here.
     */
    info->pixmap.scan_align = 4;

    /*
     * buf_align is the amount to be padded for the buffer. For example,
     * the i810fb needs a scan_align of 2 but expects it to be fed with
     * dwords, so a buf_align = 4 is required.
     */
    info->pixmap.buf_align = 4;

    /* access_align is how many bits can be accessed from the framebuffer
     * ie. some epson cards allow 16-bit access only.  Most drivers will
     * be safe with u32 here.
     *
     * NOTE: This field is currently unused.
     */
    info->pixmap.access_align = 32;
/***************************** End optional stage ***************************/

    /*
     * This should give a reasonable default video mode. The following is
     * done when we can set a video mode. 
     */
    if (!mode_option)
	mode_option = "640x480@60";	 	

    retval = fb_find_mode(&info->var, info, mode_option, NULL, 0, NULL, 8);
  
    if (!retval || retval == 4)
	return -EINVAL;			

    /* This has to been done !!! */	
    fb_alloc_cmap(&info->cmap, cmap_len, 0);
	
    /* 
     * The following is done in the case of having hardware with a static 
     * mode. If we are setting the mode ourselves we don't call this. 
     */	
    info->var = xxxfb_var;

    /*
     * For drivers that can...
     */
    xxxfb_check_var(&info->var, info);

    /*
     * Does a call to fb_set_par() before register_framebuffer needed?  This
     * will depend on you and the hardware.  If you are sure that your driver
     * is the only device in the system, a call to fb_set_par() is safe.
     *
     * Hardware in x86 systems has a VGA core.  Calling set_par() at this
     * point will corrupt the VGA console, so it might be safer to skip a
     * call to set_par here and just allow fbcon to do it for you.
     */
    /* xxxfb_set_par(info); */

    if (register_framebuffer(info) < 0)
	return -EINVAL;
    printk(KERN_INFO "fb%d: %s frame buffer device\n", info->node,
	   info->fix.id);
    pci_set_drvdata(dev, info); /* or platform_set_drvdata(pdev, info) */
    return 0;
}

    /*
     *  Cleanup
     */
/* static void __devexit xxxfb_remove(struct platform_device *pdev) */
static void __devexit xxxfb_remove(struct pci_dev *dev)
{
	struct fb_info *info = pci_get_drvdata(dev);
	/* or platform_get_drvdata(pdev); */

	if (info) {
		unregister_framebuffer(info);
		fb_dealloc_cmap(&info->cmap);
		/* ... */
		framebuffer_release(info);
	}
}

#ifdef CONFIG_PCI
#ifdef CONFIG_PM
/**
 *	xxxfb_suspend - Optional but recommended function. Suspend the device.
 *	@dev: PCI device
 *	@msg: the suspend event code.
 *
 *      See Documentation/power/devices.txt for more information
 */
static int xxxfb_suspend(struct pci_dev *dev, pm_message_t msg)
{
	struct fb_info *info = pci_get_drvdata(dev);
	struct xxxfb_par *par = info->par;

	/* suspend here */
	return 0;
}

/**
 *	xxxfb_resume - Optional but recommended function. Resume the device.
 *	@dev: PCI device
 *
 *      See Documentation/power/devices.txt for more information
 */
static int xxxfb_resume(struct pci_dev *dev)
{
	struct fb_info *info = pci_get_drvdata(dev);
	struct xxxfb_par *par = info->par;

	/* resume here */
	return 0;
}
#else
#define xxxfb_suspend NULL
#define xxxfb_resume NULL
#endif /* CONFIG_PM */

static struct pci_device_id xxxfb_id_table[] = {
	{ PCI_VENDOR_ID_XXX, PCI_DEVICE_ID_XXX,
	  PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY << 16,
	  PCI_CLASS_MASK, 0 },
	{ 0, }
};

/* For PCI drivers */
static struct pci_driver xxxfb_driver = {
	.name =		"xxxfb",
	.id_table =	xxxfb_id_table,
	.probe =	xxxfb_probe,
	.remove =	__devexit_p(xxxfb_remove),
	.suspend =      xxxfb_suspend, /* optional but recommended */
	.resume =       xxxfb_resume,  /* optional but recommended */
};

MODULE_DEVICE_TABLE(pci, xxxfb_id_table);

int __init xxxfb_init(void)
{
	/*
	 *  For kernel boot options (in 'video=xxxfb:<options>' format)
	 */
#ifndef MODULE
	char *option = NULL;

	if (fb_get_options("xxxfb", &option))
		return -ENODEV;
	xxxfb_setup(option);
#endif

	return pci_register_driver(&xxxfb_driver);
}

static void __exit xxxfb_exit(void)
{
	pci_unregister_driver(&xxxfb_driver);
}
#else /* non PCI, platform drivers */
#include <linux/platform_device.h>
/* for platform devices */

#ifdef CONFIG_PM
/**
 *	xxxfb_suspend - Optional but recommended function. Suspend the device.
 *	@dev: platform device
 *	@msg: the suspend event code.
 *
 *      See Documentation/power/devices.txt for more information
 */
static int xxxfb_suspend(struct platform_device *dev, pm_message_t msg)
{
	struct fb_info *info = platform_get_drvdata(dev);
	struct xxxfb_par *par = info->par;

	/* suspend here */
	return 0;
}

/**
 *	xxxfb_resume - Optional but recommended function. Resume the device.
 *	@dev: platform device
 *
 *      See Documentation/power/devices.txt for more information
 */
static int xxxfb_resume(struct platform_dev *dev)
{
	struct fb_info *info = platform_get_drvdata(dev);
	struct xxxfb_par *par = info->par;

	/* resume here */
	return 0;
}
#else
#define xxxfb_suspend NULL
#define xxxfb_resume NULL
#endif /* CONFIG_PM */

static struct platform_device_driver xxxfb_driver = {
	.probe = xxxfb_probe,
	.remove = xxxfb_remove,
	.suspend = xxxfb_suspend, /* optional but recommended */
	.resume = xxxfb_resume,   /* optional but recommended */
	.driver = {
		.name = "xxxfb",
	},
};

static struct platform_device *xxxfb_device;

#ifndef MODULE
    /*
     *  Setup
     */

/*
 * Only necessary if your driver takes special options,
 * otherwise we fall back on the generic fb_setup().
 */
int __init xxxfb_setup(char *options)
{
    /* Parse user speficied options (`video=xxxfb:') */
}
#endif /* MODULE */

static int __init xxxfb_init(void)
{
	int ret;
	/*
	 *  For kernel boot options (in 'video=xxxfb:<options>' format)
	 */
#ifndef MODULE
	char *option = NULL;

	if (fb_get_options("xxxfb", &option))
		return -ENODEV;
	xxxfb_setup(option);
#endif
	ret = platform_driver_register(&xxxfb_driver);

	if (!ret) {
		xxxfb_device = platform_device_register_simple("xxxfb", 0,
								NULL, 0);

		if (IS_ERR(xxxfb_device)) {
			platform_driver_unregister(&xxxfb_driver);
			ret = PTR_ERR(xxxfb_device);
		}
	}

	return ret;
}

static void __exit xxxfb_exit(void)
{
	platform_device_unregister(xxxfb_device);
	platform_driver_unregister(&xxxfb_driver);
}
#endif /* CONFIG_PCI */

/* ------------------------------------------------------------------------- */


    /*
     *  Modularization
     */

module_init(xxxfb_init);
module_exit(xxxfb_remove);

MODULE_LICENSE("GPL");