Quelle  cfag12864bfb.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0
/*
 *    Filename: cfag12864bfb.c
 *     Version: 0.1.0
 * Description: cfag12864b LCD framebuffer driver
 *     Depends: cfag12864b
 *
 *      Author: Copyright (C) Miguel Ojeda <ojeda@kernel.org>
 *        Date: 2006-10-31
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/fb.h>
#include <linux/mm.h>
#include <linux/platform_device.h>
#include <linux/cfag12864b.h>

#define CFAG12864BFB_NAME "cfag12864bfb"

static const struct fb_fix_screeninfo cfag12864bfb_fix = {
 .id = "cfag12864b",
 .type = FB_TYPE_PACKED_PIXELS,
 .visual = FB_VISUAL_MONO10,
 .xpanstep = 0,
 .ypanstep = 0,
 .ywrapstep = 0,
 .line_length = CFAG12864B_WIDTH / 8,
 .accel = FB_ACCEL_NONE,
};

static const struct fb_var_screeninfo cfag12864bfb_var = {
 .xres = CFAG12864B_WIDTH,
 .yres = CFAG12864B_HEIGHT,
 .xres_virtual = CFAG12864B_WIDTH,
 .yres_virtual = CFAG12864B_HEIGHT,
 .bits_per_pixel = 1,
 .red = { 0, 1, 0 },
 .green = { 0, 1, 0 },
 .blue = { 0, 1, 0 },
 .left_margin = 0,
 .right_margin = 0,
 .upper_margin = 0,
 .lower_margin = 0,
 .vmode = FB_VMODE_NONINTERLACED,
};

static int cfag12864bfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
{
 struct page *pages = virt_to_page(cfag12864b_buffer);

 vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);

 return vm_map_pages_zero(vma, &pages, 1);
}

static const struct fb_ops cfag12864bfb_ops = {
 .owner = THIS_MODULE,
 __FB_DEFAULT_SYSMEM_OPS_RDWR,
 __FB_DEFAULT_SYSMEM_OPS_DRAW,
 .fb_mmap = cfag12864bfb_mmap,
};

static int cfag12864bfb_probe(struct platform_device *device)
{
 int ret = -EINVAL;
 struct fb_info *info = framebuffer_alloc(0, &device->dev);

 if (!info)
  goto none;

 info->flags = FBINFO_VIRTFB;
 info->screen_buffer = cfag12864b_buffer;
 info->screen_size = CFAG12864B_SIZE;
 info->fbops = &cfag12864bfb_ops;
 info->fix = cfag12864bfb_fix;
 info->var = cfag12864bfb_var;
 info->pseudo_palette = NULL;
 info->par = NULL;

 if (register_framebuffer(info) < 0)
  goto fballoced;

 platform_set_drvdata(device, info);

 fb_info(info, "%s frame buffer device\n", info->fix.id);

 return 0;

fballoced:
 framebuffer_release(info);

none:
 return ret;
}

static void cfag12864bfb_remove(struct platform_device *device)
{
 struct fb_info *info = platform_get_drvdata(device);

 if (info) {
  unregister_framebuffer(info);
  framebuffer_release(info);
 }
}

static struct platform_driver cfag12864bfb_driver = {
 .probe = cfag12864bfb_probe,
 .remove = cfag12864bfb_remove,
 .driver = {
  .name = CFAG12864BFB_NAME,
 },
};

static struct platform_device *cfag12864bfb_device;

static int __init cfag12864bfb_init(void)
{
 int ret = -EINVAL;

 /* cfag12864b_init() must be called first */
 if (!cfag12864b_isinited()) {
  printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
   "cfag12864b is not initialized\n");
  goto none;
 }

 if (cfag12864b_enable()) {
  printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
   "can't enable cfag12864b refreshing (being used)\n");
  return -ENODEV;
 }

 ret = platform_driver_register(&cfag12864bfb_driver);

 if (!ret) {
  cfag12864bfb_device =
   platform_device_alloc(CFAG12864BFB_NAME, 0);

  if (cfag12864bfb_device)
   ret = platform_device_add(cfag12864bfb_device);
  else
   ret = -ENOMEM;

  if (ret) {
   platform_device_put(cfag12864bfb_device);
   platform_driver_unregister(&cfag12864bfb_driver);
  }
 }

none:
 return ret;
}

static void __exit cfag12864bfb_exit(void)
{
 platform_device_unregister(cfag12864bfb_device);
 platform_driver_unregister(&cfag12864bfb_driver);
 cfag12864b_disable();
}

module_init(cfag12864bfb_init);
module_exit(cfag12864bfb_exit);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Miguel Ojeda ");
MODULE_DESCRIPTION("cfag12864b LCD framebuffer driver");