arch/sh/boards/mach-landisk/gio.c

   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
  24 static dev_t dev;
  25 static struct cdev *cdev_p;
  26 static int openCnt;
  27
  28 static 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
  47 static 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
  58 static 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
 122 static 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
 130 static 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
 157 static void __exit gio_exit(void)
 158 {
 159         cdev_del(cdev_p);
 160         unregister_chrdev_region(dev, DEVCOUNT);
 161 }
 162
 163 module_init(gio_init);
 164 module_exit(gio_exit);
 165
 166 MODULE_LICENSE("GPL");