linux/drivers/auxdisplay/cfag12864bfb.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *    Filename: cfag12864bfb.c
   4 *     Version: 0.1.0
   5 * Description: cfag12864b LCD framebuffer driver
   6 *     Depends: cfag12864b
   7 *
   8 *      Author: Copyright (C) Miguel Ojeda <ojeda@kernel.org>
   9 *        Date: 2006-10-31
  10 */
  11
  12#include <linux/init.h>
  13#include <linux/module.h>
  14#include <linux/kernel.h>
  15#include <linux/delay.h>
  16#include <linux/errno.h>
  17#include <linux/fb.h>
  18#include <linux/mm.h>
  19#include <linux/platform_device.h>
  20#include <linux/string.h>
  21#include <linux/uaccess.h>
  22#include <linux/cfag12864b.h>
  23
  24#define CFAG12864BFB_NAME "cfag12864bfb"
  25
  26static const struct fb_fix_screeninfo cfag12864bfb_fix = {
  27        .id = "cfag12864b",
  28        .type = FB_TYPE_PACKED_PIXELS,
  29        .visual = FB_VISUAL_MONO10,
  30        .xpanstep = 0,
  31        .ypanstep = 0,
  32        .ywrapstep = 0,
  33        .line_length = CFAG12864B_WIDTH / 8,
  34        .accel = FB_ACCEL_NONE,
  35};
  36
  37static const struct fb_var_screeninfo cfag12864bfb_var = {
  38        .xres = CFAG12864B_WIDTH,
  39        .yres = CFAG12864B_HEIGHT,
  40        .xres_virtual = CFAG12864B_WIDTH,
  41        .yres_virtual = CFAG12864B_HEIGHT,
  42        .bits_per_pixel = 1,
  43        .red = { 0, 1, 0 },
  44        .green = { 0, 1, 0 },
  45        .blue = { 0, 1, 0 },
  46        .left_margin = 0,
  47        .right_margin = 0,
  48        .upper_margin = 0,
  49        .lower_margin = 0,
  50        .vmode = FB_VMODE_NONINTERLACED,
  51};
  52
  53static int cfag12864bfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
  54{
  55        struct page *pages = virt_to_page(cfag12864b_buffer);
  56
  57        return vm_map_pages_zero(vma, &pages, 1);
  58}
  59
  60static const struct fb_ops cfag12864bfb_ops = {
  61        .owner = THIS_MODULE,
  62        .fb_read = fb_sys_read,
  63        .fb_write = fb_sys_write,
  64        .fb_fillrect = sys_fillrect,
  65        .fb_copyarea = sys_copyarea,
  66        .fb_imageblit = sys_imageblit,
  67        .fb_mmap = cfag12864bfb_mmap,
  68};
  69
  70static int cfag12864bfb_probe(struct platform_device *device)
  71{
  72        int ret = -EINVAL;
  73        struct fb_info *info = framebuffer_alloc(0, &device->dev);
  74
  75        if (!info)
  76                goto none;
  77
  78        info->screen_base = (char __iomem *) cfag12864b_buffer;
  79        info->screen_size = CFAG12864B_SIZE;
  80        info->fbops = &cfag12864bfb_ops;
  81        info->fix = cfag12864bfb_fix;
  82        info->var = cfag12864bfb_var;
  83        info->pseudo_palette = NULL;
  84        info->par = NULL;
  85        info->flags = FBINFO_FLAG_DEFAULT;
  86
  87        if (register_framebuffer(info) < 0)
  88                goto fballoced;
  89
  90        platform_set_drvdata(device, info);
  91
  92        fb_info(info, "%s frame buffer device\n", info->fix.id);
  93
  94        return 0;
  95
  96fballoced:
  97        framebuffer_release(info);
  98
  99none:
 100        return ret;
 101}
 102
 103static int cfag12864bfb_remove(struct platform_device *device)
 104{
 105        struct fb_info *info = platform_get_drvdata(device);
 106
 107        if (info) {
 108                unregister_framebuffer(info);
 109                framebuffer_release(info);
 110        }
 111
 112        return 0;
 113}
 114
 115static struct platform_driver cfag12864bfb_driver = {
 116        .probe  = cfag12864bfb_probe,
 117        .remove = cfag12864bfb_remove,
 118        .driver = {
 119                .name   = CFAG12864BFB_NAME,
 120        },
 121};
 122
 123static struct platform_device *cfag12864bfb_device;
 124
 125static int __init cfag12864bfb_init(void)
 126{
 127        int ret = -EINVAL;
 128
 129        /* cfag12864b_init() must be called first */
 130        if (!cfag12864b_isinited()) {
 131                printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
 132                        "cfag12864b is not initialized\n");
 133                goto none;
 134        }
 135
 136        if (cfag12864b_enable()) {
 137                printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
 138                        "can't enable cfag12864b refreshing (being used)\n");
 139                return -ENODEV;
 140        }
 141
 142        ret = platform_driver_register(&cfag12864bfb_driver);
 143
 144        if (!ret) {
 145                cfag12864bfb_device =
 146                        platform_device_alloc(CFAG12864BFB_NAME, 0);
 147
 148                if (cfag12864bfb_device)
 149                        ret = platform_device_add(cfag12864bfb_device);
 150                else
 151                        ret = -ENOMEM;
 152
 153                if (ret) {
 154                        platform_device_put(cfag12864bfb_device);
 155                        platform_driver_unregister(&cfag12864bfb_driver);
 156                }
 157        }
 158
 159none:
 160        return ret;
 161}
 162
 163static void __exit cfag12864bfb_exit(void)
 164{
 165        platform_device_unregister(cfag12864bfb_device);
 166        platform_driver_unregister(&cfag12864bfb_driver);
 167        cfag12864b_disable();
 168}
 169
 170module_init(cfag12864bfb_init);
 171module_exit(cfag12864bfb_exit);
 172
 173MODULE_LICENSE("GPL v2");
 174MODULE_AUTHOR("Miguel Ojeda <ojeda@kernel.org>");
 175MODULE_DESCRIPTION("cfag12864b LCD framebuffer driver");
 176