arch/sparc/kernel/auxio_64.c

   1 /* auxio.c: Probing for the Sparc AUXIO register at boot time.
   2  *
   3  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
   4  *
   5  * Refactoring for unified NCR/PCIO support 2002 Eric Brower (ebrower@usa.net)
   6  */
   7
   8 #include <linux/module.h>
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11 #include <linux/ioport.h>
  12 #include <linux/of_device.h>
  13
  14 #include <asm/prom.h>
  15 #include <asm/io.h>
  16 #include <asm/auxio.h>
  17
  18 void __iomem *auxio_register = NULL;
  19 EXPORT_SYMBOL(auxio_register);
  20
  21 enum auxio_type {
  22         AUXIO_TYPE_NODEV,
  23         AUXIO_TYPE_SBUS,
  24         AUXIO_TYPE_EBUS
  25 };
  26
  27 static enum auxio_type auxio_devtype = AUXIO_TYPE_NODEV;
  28 static DEFINE_SPINLOCK(auxio_lock);
  29
  30 static void __auxio_rmw(u8 bits_on, u8 bits_off, int ebus)
  31 {
  32         if (auxio_register) {
  33                 unsigned long flags;
  34                 u8 regval, newval;
  35
  36                 spin_lock_irqsave(&auxio_lock, flags);
  37
  38                 regval = (ebus ?
  39                           (u8) readl(auxio_register) :
  40                           sbus_readb(auxio_register));
  41                 newval =  regval | bits_on;
  42                 newval &= ~bits_off;
  43                 if (!ebus)
  44                         newval &= ~AUXIO_AUX1_MASK;
  45                 if (ebus)
  46                         writel((u32) newval, auxio_register);
  47                 else
  48                         sbus_writeb(newval, auxio_register);
  49
  50                 spin_unlock_irqrestore(&auxio_lock, flags);
  51         }
  52 }
  53
  54 static void __auxio_set_bit(u8 bit, int on, int ebus)
  55 {
  56         u8 bits_on = (ebus ? AUXIO_PCIO_LED : AUXIO_AUX1_LED);
  57         u8 bits_off = 0;
  58
  59         if (!on) {
  60                 u8 tmp = bits_off;
  61                 bits_off = bits_on;
  62                 bits_on = tmp;
  63         }
  64         __auxio_rmw(bits_on, bits_off, ebus);
  65 }
  66
  67 void auxio_set_led(int on)
  68 {
  69         int ebus = auxio_devtype == AUXIO_TYPE_EBUS;
  70         u8 bit;
  71
  72         bit = (ebus ? AUXIO_PCIO_LED : AUXIO_AUX1_LED);
  73         __auxio_set_bit(bit, on, ebus);
  74 }
  75 EXPORT_SYMBOL(auxio_set_led);
  76
  77 static void __auxio_sbus_set_lte(int on)
  78 {
  79         __auxio_set_bit(AUXIO_AUX1_LTE, on, 0);
  80 }
  81
  82 void auxio_set_lte(int on)
  83 {
  84         switch(auxio_devtype) {
  85         case AUXIO_TYPE_SBUS:
  86                 __auxio_sbus_set_lte(on);
  87                 break;
  88         case AUXIO_TYPE_EBUS:
  89                 /* FALL-THROUGH */
  90         default:
  91                 break;
  92         }
  93 }
  94 EXPORT_SYMBOL(auxio_set_lte);
  95
  96 static const struct of_device_id auxio_match[] = {
  97         {
  98                 .name = "auxio",
  99         },
 100         {},
 101 };
 102
 103 MODULE_DEVICE_TABLE(of, auxio_match);
 104
 105 static int auxio_probe(struct platform_device *dev)
 106 {
 107         struct device_node *dp = dev->dev.of_node;
 108         unsigned long size;
 109
 110         if (!strcmp(dp->parent->name, "ebus")) {
 111                 auxio_devtype = AUXIO_TYPE_EBUS;
 112                 size = sizeof(u32);
 113         } else if (!strcmp(dp->parent->name, "sbus")) {
 114                 auxio_devtype = AUXIO_TYPE_SBUS;
 115                 size = 1;
 116         } else {
 117                 printk("auxio: Unknown parent bus type [%s]\n",
 118                        dp->parent->name);
 119                 return -ENODEV;
 120         }
 121         auxio_register = of_ioremap(&dev->resource[0], 0, size, "auxio");
 122         if (!auxio_register)
 123                 return -ENODEV;
 124
 125         printk(KERN_INFO "AUXIO: Found device at %s\n",
 126                dp->full_name);
 127
 128         if (auxio_devtype == AUXIO_TYPE_EBUS)
 129                 auxio_set_led(AUXIO_LED_ON);
 130
 131         return 0;
 132 }
 133
 134 static struct platform_driver auxio_driver = {
 135         .probe          = auxio_probe,
 136         .driver = {
 137                 .name = "auxio",
 138                 .of_match_table = auxio_match,
 139         },
 140 };
 141
 142 static int __init auxio_init(void)
 143 {
 144         return platform_driver_register(&auxio_driver);
 145 }
 146
 147 /* Must be after subsys_initcall() so that busses are probed.  Must
 148  * be before device_initcall() because things like the floppy driver
 149  * need to use the AUXIO register.
 150  */
 151 fs_initcall(auxio_init);