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); 152