linux/arch/sh/boards/mach-landisk/gio.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * arch/sh/boards/landisk/gio.c - driver for landisk
   4 *
   5 * This driver will also support the I-O DATA Device, Inc. LANDISK Board.
   6 * LANDISK and USL-5P Button, LED and GIO driver drive function.
   7 *
   8 *   Copylight (C) 2006 kogiidena
   9 *   Copylight (C) 2002 Atom Create Engineering Co., Ltd. *
  10 */
  11#include <linux/module.h>
  12#include <linux/init.h>
  13#include <linux/kdev_t.h>
  14#include <linux/cdev.h>
  15#include <linux/fs.h>
  16#include <asm/io.h>
  17#include <linux/uaccess.h>
  18#include <mach-landisk/mach/gio.h>
  19#include <mach-landisk/mach/iodata_landisk.h>
  20
  21#define DEVCOUNT                4
  22#define GIO_MINOR               2       /* GIO minor no. */
  23
  24static dev_t dev;
  25static struct cdev *cdev_p;
  26static int openCnt;
  27
  28static int gio_open(struct inode *inode, struct file *filp)
  29{
  30        int minor;
  31        int ret = -ENOENT;
  32
  33        preempt_disable();
  34        minor = MINOR(inode->i_rdev);
  35        if (minor < DEVCOUNT) {
  36                if (openCnt > 0) {
  37                        ret = -EALREADY;
  38                } else {
  39                        openCnt++;
  40                        ret = 0;
  41                }
  42        }
  43        preempt_enable();
  44        return ret;
  45}
  46
  47static int gio_close(struct inode *inode, struct file *filp)
  48{
  49        int minor;
  50
  51        minor = MINOR(inode->i_rdev);
  52        if (minor < DEVCOUNT) {
  53                openCnt--;
  54        }
  55        return 0;
  56}
  57
  58static long gio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
  59{
  60        unsigned int data;
  61        static unsigned int addr = 0;
  62
  63        if (cmd & 0x01) {       /* write */
  64                if (copy_from_user(&data, (int *)arg, sizeof(int))) {
  65                        return -EFAULT;
  66                }
  67        }
  68
  69        switch (cmd) {
  70        case GIODRV_IOCSGIOSETADDR:     /* address set */
  71                addr = data;
  72                break;
  73
  74        case GIODRV_IOCSGIODATA1:       /* write byte */
  75                __raw_writeb((unsigned char)(0x0ff & data), addr);
  76                break;
  77
  78        case GIODRV_IOCSGIODATA2:       /* write word */
  79                if (addr & 0x01) {
  80                        return -EFAULT;
  81                }
  82                __raw_writew((unsigned short int)(0x0ffff & data), addr);
  83                break;
  84
  85        case GIODRV_IOCSGIODATA4:       /* write long */
  86                if (addr & 0x03) {
  87                        return -EFAULT;
  88                }
  89                __raw_writel(data, addr);
  90                break;
  91
  92        case GIODRV_IOCGGIODATA1:       /* read byte */
  93                data = __raw_readb(addr);
  94                break;
  95
  96        case GIODRV_IOCGGIODATA2:       /* read word */
  97                if (addr & 0x01) {
  98                        return -EFAULT;
  99                }
 100                data = __raw_readw(addr);
 101                break;
 102
 103        case GIODRV_IOCGGIODATA4:       /* read long */
 104                if (addr & 0x03) {
 105                        return -EFAULT;
 106                }
 107                data = __raw_readl(addr);
 108                break;
 109        default:
 110                return -EFAULT;
 111                break;
 112        }
 113
 114        if ((cmd & 0x01) == 0) {        /* read */
 115                if (copy_to_user((int *)arg, &data, sizeof(int))) {
 116                        return -EFAULT;
 117                }
 118        }
 119        return 0;
 120}
 121
 122static const struct file_operations gio_fops = {
 123        .owner = THIS_MODULE,
 124        .open = gio_open,       /* open */
 125        .release = gio_close,   /* release */
 126        .unlocked_ioctl = gio_ioctl,
 127        .llseek = noop_llseek,
 128};
 129
 130static int __init gio_init(void)
 131{
 132        int error;
 133
 134        printk(KERN_INFO "gio: driver initialized\n");
 135
 136        openCnt = 0;
 137
 138        if ((error = alloc_chrdev_region(&dev, 0, DEVCOUNT, "gio")) < 0) {
 139                printk(KERN_ERR
 140                       "gio: Couldn't alloc_chrdev_region, error=%d\n",
 141                       error);
 142                return 1;
 143        }
 144
 145        cdev_p = cdev_alloc();
 146        cdev_p->ops = &gio_fops;
 147        error = cdev_add(cdev_p, dev, DEVCOUNT);
 148        if (error) {
 149                printk(KERN_ERR
 150                       "gio: Couldn't cdev_add, error=%d\n", error);
 151                return 1;
 152        }
 153
 154        return 0;
 155}
 156
 157static void __exit gio_exit(void)
 158{
 159        cdev_del(cdev_p);
 160        unregister_chrdev_region(dev, DEVCOUNT);
 161}
 162
 163module_init(gio_init);
 164module_exit(gio_exit);
 165
 166MODULE_LICENSE("GPL");
 167