drivers/sbus/char/uctrl.c

   1 /* $Id: uctrl.c,v 1.2 1999/09/07 23:11:08 shadow Exp $
   2  * uctrl.c: TS102 Microcontroller interface on Tadpole Sparcbook 3
   3  *
   4  * Copyright 1999 Derrick J Brashear (shadow@dementia.org)
   5  */
   6
   7 #include <linux/config.h>
   8 #include <linux/module.h>
   9 #include <linux/sched.h>
  10 #include <linux/errno.h>
  11 #include <linux/delay.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/malloc.h>
  14 #include <linux/ioport.h>
  15 #include <linux/init.h>
  16 #include <linux/miscdevice.h>
  17 #include <linux/mm.h>
  18
  19 #include <asm/openprom.h>
  20 #include <asm/oplib.h>
  21 #include <asm/system.h>
  22 #include <asm/irq.h>
  23 #include <asm/io.h>
  24 #include <asm/pgtable.h>
  25 #include <asm/sbus.h>
  26
  27 #define UCTRL_MINOR     174
  28
  29 struct uctrl_driver {
  30         volatile u32 *regs;
  31         int irq;
  32 };
  33
  34 static struct uctrl_driver drv;
  35
  36 static loff_t
  37 uctrl_llseek(struct file *file, loff_t offset, int type)
  38 {
  39         return -ESPIPE;
  40 }
  41
  42 static int
  43 uctrl_ioctl(struct inode *inode, struct file *file,
  44               unsigned int cmd, unsigned long arg)
  45 {
  46         switch (cmd) {
  47                 default:
  48                         return -EINVAL;
  49         }
  50         return 0;
  51 }
  52
  53 static int
  54 uctrl_open(struct inode *inode, struct file *file)
  55 {
  56         MOD_INC_USE_COUNT;
  57         return 0;
  58 }
  59
  60 static int
  61 uctrl_release(struct inode *inode, struct file *file)
  62 {
  63         MOD_DEC_USE_COUNT;
  64         return 0;
  65 }
  66
  67 void uctrl_interrupt(int irq, void *dev_id, struct pt_regs *regs)
  68 {
  69         struct uctrl_driver *driver = (struct uctrl_driver *)dev_id;
  70         printk("in uctrl_interrupt\n");
  71 }
  72
  73 static struct file_operations uctrl_fops = {
  74         uctrl_llseek,
  75         NULL,           /* read */
  76         NULL,           /* write */
  77         NULL,           /* readdir */
  78         NULL,           /* poll */
  79         uctrl_ioctl,
  80         NULL,           /* mmap */
  81         uctrl_open,
  82         NULL,           /* flush */
  83         uctrl_release
  84 };
  85
  86 static struct miscdevice uctrl_dev = {
  87         UCTRL_MINOR,
  88         "uctrl",
  89         &uctrl_fops
  90 };
  91
  92 #ifdef MODULE
  93 int init_module(void)
  94 #else
  95 __initfunc(int uctrl_init(void))
  96 #endif
  97 {
  98         struct uctrl_driver *driver = &drv;
  99         int len;
 100         struct linux_prom_irqs tmp_irq[2];
 101         unsigned int vaddr[2] = { 0, 0 };
 102         int tmpnode, uctrlnode = prom_getchild(prom_root_node);
 103
 104         tmpnode = prom_searchsiblings(uctrlnode, "obio");
 105
 106         if (tmpnode)
 107           uctrlnode = prom_getchild(tmpnode);
 108
 109         uctrlnode = prom_searchsiblings(uctrlnode, "uctrl");
 110
 111         if (!uctrlnode)
 112                 return -ENODEV;
 113
 114         /* the prom mapped it for us */
 115         len = prom_getproperty(uctrlnode, "address", (void *) vaddr,
 116                                sizeof(vaddr));
 117         driver->regs = vaddr[0];
 118
 119         len = prom_getproperty(uctrlnode, "intr", (char *) tmp_irq,
 120                                sizeof(tmp_irq));
 121         if(!driver->irq)
 122                 driver->irq = tmp_irq[0].pri;
 123
 124         request_irq(driver->irq, uctrl_interrupt, 0,
 125                     "uctrl", driver);
 126
 127         enable_irq(driver->irq);
 128
 129         if (misc_register(&uctrl_dev)) {
 130                 printk("%s: unable to get misc minor %d\n",
 131                        __FUNCTION__, uctrl_dev.minor);
 132                 disable_irq(driver->irq);
 133                 free_irq(driver->irq, driver);
 134                 return -ENODEV;
 135         }
 136
 137         printk(KERN_INFO, "uctrl: 0x%x (irq %d)\n", driver->regs, __irq_itoa(driver->irq));
 138         return 0;
 139 }
 140
 141
 142 #ifdef MODULE
 143 void cleanup_module(void)
 144 {
 145         struct uctrl_driver *driver = &drv;
 146
 147         misc_deregister(&uctrl_dev);
 148         if (driver->irq) {
 149                 disable_irq(driver->irq);
 150                 free_irq(driver->irq, driver);
 151         }
 152         if (driver->regs)
 153                 driver->regs = 0;
 154 }
 155 #endif