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

   1 /*
   2  * arch/sh/boards/landisk/gio.c - driver for landisk
   3  *
   4  * This driver will also support the I-O DATA Device, Inc. LANDISK Board.
   5  * LANDISK and USL-5P Button, LED and GIO driver drive function.
   6  *
   7  *   Copylight (C) 2006 kogiidena
   8  *   Copylight (C) 2002 Atom Create Engineering Co., Ltd. *
   9  *
  10  * This file is subject to the terms and conditions of the GNU General Public
  11  * License.  See the file "COPYING" in the main directory of this archive
  12  * for more details.
  13  *
  14  */
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/smp_lock.h>
  18 #include <linux/kdev_t.h>
  19 #include <linux/cdev.h>
  20 #include <linux/fs.h>
  21 #include <asm/io.h>
  22 #include <asm/uaccess.h>
  23 #include <mach-landisk/mach/gio.h>
  24 #include <mach-landisk/mach/iodata_landisk.h>
  25
  26 #define DEVCOUNT                4
  27 #define GIO_MINOR               2       /* GIO minor no. */
  28
  29 static dev_t dev;
  30 static struct cdev *cdev_p;
  31 static int openCnt;
  32
  33 static int gio_open(struct inode *inode, struct file *filp)
  34 {
  35         int minor;
  36         int ret = -ENOENT;
  37
  38         lock_kernel();
  39         minor = MINOR(inode->i_rdev);
  40         if (minor < DEVCOUNT) {
  41                 if (openCnt > 0) {
  42                         ret = -EALREADY;
  43                 } else {
  44                         openCnt++;
  45                         ret = 0;
  46                 }
  47         }
  48         unlock_kernel();
  49         return ret;
  50 }
  51
  52 static int gio_close(struct inode *inode, struct file *filp)
  53 {
  54         int minor;
  55
  56         minor = MINOR(inode->i_rdev);
  57         if (minor < DEVCOUNT) {
  58                 openCnt--;
  59         }
  60         return 0;
  61 }
  62
  63 static int gio_ioctl(struct inode *inode, struct file *filp,
  64                              unsigned int cmd, unsigned long arg)
  65 {
  66         unsigned int data;
  67         static unsigned int addr = 0;
  68
  69         if (cmd & 0x01) {       /* write */
  70                 if (copy_from_user(&data, (int *)arg, sizeof(int))) {
  71                         return -EFAULT;
  72                 }
  73         }
  74
  75         switch (cmd) {
  76         case GIODRV_IOCSGIOSETADDR:     /* address set */
  77                 addr = data;
  78                 break;
  79
  80         case GIODRV_IOCSGIODATA1:       /* write byte */
  81                 ctrl_outb((unsigned char)(0x0ff & data), addr);
  82                 break;
  83
  84         case GIODRV_IOCSGIODATA2:       /* write word */
  85                 if (addr & 0x01) {
  86                         return -EFAULT;
  87                 }
  88                 ctrl_outw((unsigned short int)(0x0ffff & data), addr);
  89                 break;
  90
  91         case GIODRV_IOCSGIODATA4:       /* write long */
  92                 if (addr & 0x03) {
  93                         return -EFAULT;
  94                 }
  95                 ctrl_outl(data, addr);
  96                 break;
  97
  98         case GIODRV_IOCGGIODATA1:       /* read byte */
  99                 data = ctrl_inb(addr);
 100                 break;
 101
 102         case GIODRV_IOCGGIODATA2:       /* read word */
 103                 if (addr & 0x01) {
 104                         return -EFAULT;
 105                 }
 106                 data = ctrl_inw(addr);
 107                 break;
 108
 109         case GIODRV_IOCGGIODATA4:       /* read long */
 110                 if (addr & 0x03) {
 111                         return -EFAULT;
 112                 }
 113                 data = ctrl_inl(addr);
 114                 break;
 115         default:
 116                 return -EFAULT;
 117                 break;
 118         }
 119
 120         if ((cmd & 0x01) == 0) {        /* read */
 121                 if (copy_to_user((int *)arg, &data, sizeof(int))) {
 122                         return -EFAULT;
 123                 }
 124         }
 125         return 0;
 126 }
 127
 128 static const struct file_operations gio_fops = {
 129         .owner = THIS_MODULE,
 130         .open = gio_open,       /* open */
 131         .release = gio_close,   /* release */
 132         .ioctl = gio_ioctl,     /* ioctl */
 133 };
 134
 135 static int __init gio_init(void)
 136 {
 137         int error;
 138
 139         printk(KERN_INFO "gio: driver initialized\n");
 140
 141         openCnt = 0;
 142
 143         if ((error = alloc_chrdev_region(&dev, 0, DEVCOUNT, "gio")) < 0) {
 144                 printk(KERN_ERR
 145                        "gio: Couldn't alloc_chrdev_region, error=%d\n",
 146                        error);
 147                 return 1;
 148         }
 149
 150         cdev_p = cdev_alloc();
 151         cdev_p->ops = &gio_fops;
 152         error = cdev_add(cdev_p, dev, DEVCOUNT);
 153         if (error) {
 154                 printk(KERN_ERR
 155                        "gio: Couldn't cdev_add, error=%d\n", error);
 156                 return 1;
 157         }
 158
 159         return 0;
 160 }
 161
 162 static void __exit gio_exit(void)
 163 {
 164         cdev_del(cdev_p);
 165         unregister_chrdev_region(dev, DEVCOUNT);
 166 }
 167
 168 module_init(gio_init);
 169 module_exit(gio_exit);
 170
 171 MODULE_LICENSE("GPL");