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/kdev_t.h>
  18 #include <linux/cdev.h>
  19 #include <linux/fs.h>
  20 #include <asm/io.h>
  21 #include <asm/uaccess.h>
  22 #include <mach-landisk/mach/gio.h>
  23 #include <mach-landisk/mach/iodata_landisk.h>
  24
  25 #define DEVCOUNT                4
  26 #define GIO_MINOR               2       /* GIO minor no. */
  27
  28 static dev_t dev;
  29 static struct cdev *cdev_p;
  30 static int openCnt;
  31
  32 static int gio_open(struct inode *inode, struct file *filp)
  33 {
  34         int minor;
  35         int ret = -ENOENT;
  36
  37         preempt_disable();
  38         minor = MINOR(inode->i_rdev);
  39         if (minor < DEVCOUNT) {
  40                 if (openCnt > 0) {
  41                         ret = -EALREADY;
  42                 } else {
  43                         openCnt++;
  44                         ret = 0;
  45                 }
  46         }
  47         preempt_enable();
  48         return ret;
  49 }
  50
  51 static int gio_close(struct inode *inode, struct file *filp)
  52 {
  53         int minor;
  54
  55         minor = MINOR(inode->i_rdev);
  56         if (minor < DEVCOUNT) {
  57                 openCnt--;
  58         }
  59         return 0;
  60 }
  61
  62 static long gio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
  63 {
  64         unsigned int data;
  65         static unsigned int addr = 0;
  66
  67         if (cmd & 0x01) {       /* write */
  68                 if (copy_from_user(&data, (int *)arg, sizeof(int))) {
  69                         return -EFAULT;
  70                 }
  71         }
  72
  73         switch (cmd) {
  74         case GIODRV_IOCSGIOSETADDR:     /* address set */
  75                 addr = data;
  76                 break;
  77
  78         case GIODRV_IOCSGIODATA1:       /* write byte */
  79                 __raw_writeb((unsigned char)(0x0ff & data), addr);
  80                 break;
  81
  82         case GIODRV_IOCSGIODATA2:       /* write word */
  83                 if (addr & 0x01) {
  84                         return -EFAULT;
  85                 }
  86                 __raw_writew((unsigned short int)(0x0ffff & data), addr);
  87                 break;
  88
  89         case GIODRV_IOCSGIODATA4:       /* write long */
  90                 if (addr & 0x03) {
  91                         return -EFAULT;
  92                 }
  93                 __raw_writel(data, addr);
  94                 break;
  95
  96         case GIODRV_IOCGGIODATA1:       /* read byte */
  97                 data = __raw_readb(addr);
  98                 break;
  99
 100         case GIODRV_IOCGGIODATA2:       /* read word */
 101                 if (addr & 0x01) {
 102                         return -EFAULT;
 103                 }
 104                 data = __raw_readw(addr);
 105                 break;
 106
 107         case GIODRV_IOCGGIODATA4:       /* read long */
 108                 if (addr & 0x03) {
 109                         return -EFAULT;
 110                 }
 111                 data = __raw_readl(addr);
 112                 break;
 113         default:
 114                 return -EFAULT;
 115                 break;
 116         }
 117
 118         if ((cmd & 0x01) == 0) {        /* read */
 119                 if (copy_to_user((int *)arg, &data, sizeof(int))) {
 120                         return -EFAULT;
 121                 }
 122         }
 123         return 0;
 124 }
 125
 126 static const struct file_operations gio_fops = {
 127         .owner = THIS_MODULE,
 128         .open = gio_open,       /* open */
 129         .release = gio_close,   /* release */
 130         .unlocked_ioctl = gio_ioctl,
 131         .llseek = noop_llseek,
 132 };
 133
 134 static int __init gio_init(void)
 135 {
 136         int error;
 137
 138         printk(KERN_INFO "gio: driver initialized\n");
 139
 140         openCnt = 0;
 141
 142         if ((error = alloc_chrdev_region(&dev, 0, DEVCOUNT, "gio")) < 0) {
 143                 printk(KERN_ERR
 144                        "gio: Couldn't alloc_chrdev_region, error=%d\n",
 145                        error);
 146                 return 1;
 147         }
 148
 149         cdev_p = cdev_alloc();
 150         cdev_p->ops = &gio_fops;
 151         error = cdev_add(cdev_p, dev, DEVCOUNT);
 152         if (error) {
 153                 printk(KERN_ERR
 154                        "gio: Couldn't cdev_add, error=%d\n", error);
 155                 return 1;
 156         }
 157
 158         return 0;
 159 }
 160
 161 static void __exit gio_exit(void)
 162 {
 163         cdev_del(cdev_p);
 164         unregister_chrdev_region(dev, DEVCOUNT);
 165 }
 166
 167 module_init(gio_init);
 168 module_exit(gio_exit);
 169
 170 MODULE_LICENSE("GPL");