staging:iio:dac:ad5791: Allow asymmetrical reference voltages
[zen-stable.git] / arch / sparc / kernel / auxio_32.c
blobacf5151f3c1d7b9ffe24012bbe0d0047107dec1f
1 /* auxio.c: Probing for the Sparc AUXIO register at boot time.
3 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
4 */
6 #include <linux/stddef.h>
7 #include <linux/init.h>
8 #include <linux/spinlock.h>
9 #include <linux/of.h>
10 #include <linux/of_device.h>
11 #include <asm/oplib.h>
12 #include <asm/io.h>
13 #include <asm/auxio.h>
14 #include <asm/string.h> /* memset(), Linux has no bzero() */
16 /* Probe and map in the Auxiliary I/O register */
18 /* auxio_register is not static because it is referenced
19 * in entry.S::floppy_tdone
21 void __iomem *auxio_register = NULL;
22 static DEFINE_SPINLOCK(auxio_lock);
24 void __init auxio_probe(void)
26 phandle node, auxio_nd;
27 struct linux_prom_registers auxregs[1];
28 struct resource r;
30 switch (sparc_cpu_model) {
31 case sparc_leon:
32 case sun4d:
33 case sun4:
34 return;
35 default:
36 break;
38 node = prom_getchild(prom_root_node);
39 auxio_nd = prom_searchsiblings(node, "auxiliary-io");
40 if(!auxio_nd) {
41 node = prom_searchsiblings(node, "obio");
42 node = prom_getchild(node);
43 auxio_nd = prom_searchsiblings(node, "auxio");
44 if(!auxio_nd) {
45 #ifdef CONFIG_PCI
46 /* There may be auxio on Ebus */
47 return;
48 #else
49 if(prom_searchsiblings(node, "leds")) {
50 /* VME chassis sun4m machine, no auxio exists. */
51 return;
53 prom_printf("Cannot find auxio node, cannot continue...\n");
54 prom_halt();
55 #endif
58 if(prom_getproperty(auxio_nd, "reg", (char *) auxregs, sizeof(auxregs)) <= 0)
59 return;
60 prom_apply_obio_ranges(auxregs, 0x1);
61 /* Map the register both read and write */
62 r.flags = auxregs[0].which_io & 0xF;
63 r.start = auxregs[0].phys_addr;
64 r.end = auxregs[0].phys_addr + auxregs[0].reg_size - 1;
65 auxio_register = of_ioremap(&r, 0, auxregs[0].reg_size, "auxio");
66 /* Fix the address on sun4m and sun4c. */
67 if((((unsigned long) auxregs[0].phys_addr) & 3) == 3 ||
68 sparc_cpu_model == sun4c)
69 auxio_register += (3 - ((unsigned long)auxio_register & 3));
71 set_auxio(AUXIO_LED, 0);
74 unsigned char get_auxio(void)
76 if(auxio_register)
77 return sbus_readb(auxio_register);
78 return 0;
80 EXPORT_SYMBOL(get_auxio);
82 void set_auxio(unsigned char bits_on, unsigned char bits_off)
84 unsigned char regval;
85 unsigned long flags;
86 spin_lock_irqsave(&auxio_lock, flags);
87 switch(sparc_cpu_model) {
88 case sun4c:
89 regval = sbus_readb(auxio_register);
90 sbus_writeb(((regval | bits_on) & ~bits_off) | AUXIO_ORMEIN,
91 auxio_register);
92 break;
93 case sun4m:
94 if(!auxio_register)
95 break; /* VME chassis sun4m, no auxio. */
96 regval = sbus_readb(auxio_register);
97 sbus_writeb(((regval | bits_on) & ~bits_off) | AUXIO_ORMEIN4M,
98 auxio_register);
99 break;
100 case sun4d:
101 break;
102 default:
103 panic("Can't set AUXIO register on this machine.");
105 spin_unlock_irqrestore(&auxio_lock, flags);
107 EXPORT_SYMBOL(set_auxio);
109 /* sun4m power control register (AUXIO2) */
111 volatile unsigned char * auxio_power_register = NULL;
113 void __init auxio_power_probe(void)
115 struct linux_prom_registers regs;
116 phandle node;
117 struct resource r;
119 /* Attempt to find the sun4m power control node. */
120 node = prom_getchild(prom_root_node);
121 node = prom_searchsiblings(node, "obio");
122 node = prom_getchild(node);
123 node = prom_searchsiblings(node, "power");
124 if (node == 0 || (s32)node == -1)
125 return;
127 /* Map the power control register. */
128 if (prom_getproperty(node, "reg", (char *)&regs, sizeof(regs)) <= 0)
129 return;
130 prom_apply_obio_ranges(&regs, 1);
131 memset(&r, 0, sizeof(r));
132 r.flags = regs.which_io & 0xF;
133 r.start = regs.phys_addr;
134 r.end = regs.phys_addr + regs.reg_size - 1;
135 auxio_power_register = (unsigned char *) of_ioremap(&r, 0,
136 regs.reg_size, "auxpower");
138 /* Display a quick message on the console. */
139 if (auxio_power_register)
140 printk(KERN_INFO "Power off control detected.\n");