LXR linux/arch/sparc/kernel/auxio

   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
  18void __iomem *auxio_register = NULL;
  19EXPORT_SYMBOL(auxio_register);
  20
  21enum auxio_type {
  22        AUXIO_TYPE_NODEV,
  23        AUXIO_TYPE_SBUS,
  24        AUXIO_TYPE_EBUS
  25};
  26
  27static enum auxio_type auxio_devtype = AUXIO_TYPE_NODEV;
  28static DEFINE_SPINLOCK(auxio_lock);
  29
  30static 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
  54static 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
  67void 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}
  75EXPORT_SYMBOL(auxio_set_led);
  76
  77static void __auxio_sbus_set_lte(int on)
  78{
  79        __auxio_set_bit(AUXIO_AUX1_LTE, on, 0);
  80}
  81
  82void 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}
  94EXPORT_SYMBOL(auxio_set_lte);
  95
  96static const struct of_device_id auxio_match[] = {
  97        {
  98                .name = "auxio",
  99        },
 100        {},
 101};
 102
 103MODULE_DEVICE_TABLE(of, auxio_match);
 104
 105static 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
 134static struct platform_driver auxio_driver = {
 135        .probe          = auxio_probe,
 136        .driver = {
 137                .name = "auxio",
 138                .of_match_table = auxio_match,
 139        },
 140};
 141
 142static 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 */
 151fs_initcall(auxio_init);
 152