1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* auxio.c: Probing for the Sparc AUXIO register at boot time. |
3 | * |
4 | * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) |
5 | * |
6 | * Refactoring for unified NCR/PCIO support 2002 Eric Brower (ebrower@usa.net) |
7 | */ |
8 | |
9 | #include <linux/module.h> |
10 | #include <linux/kernel.h> |
11 | #include <linux/init.h> |
12 | #include <linux/ioport.h> |
13 | #include <linux/of.h> |
14 | #include <linux/platform_device.h> |
15 | |
16 | #include <asm/prom.h> |
17 | #include <asm/io.h> |
18 | #include <asm/auxio.h> |
19 | |
20 | void __iomem *auxio_register = NULL; |
21 | EXPORT_SYMBOL(auxio_register); |
22 | |
23 | enum auxio_type { |
24 | AUXIO_TYPE_NODEV, |
25 | AUXIO_TYPE_SBUS, |
26 | AUXIO_TYPE_EBUS |
27 | }; |
28 | |
29 | static enum auxio_type auxio_devtype = AUXIO_TYPE_NODEV; |
30 | static DEFINE_SPINLOCK(auxio_lock); |
31 | |
32 | static void __auxio_rmw(u8 bits_on, u8 bits_off, int ebus) |
33 | { |
34 | if (auxio_register) { |
35 | unsigned long flags; |
36 | u8 regval, newval; |
37 | |
38 | spin_lock_irqsave(&auxio_lock, flags); |
39 | |
40 | regval = (ebus ? |
41 | (u8) readl(addr: auxio_register) : |
42 | sbus_readb(auxio_register)); |
43 | newval = regval | bits_on; |
44 | newval &= ~bits_off; |
45 | if (!ebus) |
46 | newval &= ~AUXIO_AUX1_MASK; |
47 | if (ebus) |
48 | writel(val: (u32) newval, addr: auxio_register); |
49 | else |
50 | sbus_writeb(newval, auxio_register); |
51 | |
52 | spin_unlock_irqrestore(lock: &auxio_lock, flags); |
53 | } |
54 | } |
55 | |
56 | static void __auxio_set_bit(u8 bit, int on, int ebus) |
57 | { |
58 | u8 bits_on = (ebus ? AUXIO_PCIO_LED : AUXIO_AUX1_LED); |
59 | u8 bits_off = 0; |
60 | |
61 | if (!on) { |
62 | u8 tmp = bits_off; |
63 | bits_off = bits_on; |
64 | bits_on = tmp; |
65 | } |
66 | __auxio_rmw(bits_on, bits_off, ebus); |
67 | } |
68 | |
69 | void auxio_set_led(int on) |
70 | { |
71 | int ebus = auxio_devtype == AUXIO_TYPE_EBUS; |
72 | u8 bit; |
73 | |
74 | bit = (ebus ? AUXIO_PCIO_LED : AUXIO_AUX1_LED); |
75 | __auxio_set_bit(bit, on, ebus); |
76 | } |
77 | EXPORT_SYMBOL(auxio_set_led); |
78 | |
79 | static void __auxio_sbus_set_lte(int on) |
80 | { |
81 | __auxio_set_bit(bit: AUXIO_AUX1_LTE, on, ebus: 0); |
82 | } |
83 | |
84 | void auxio_set_lte(int on) |
85 | { |
86 | switch(auxio_devtype) { |
87 | case AUXIO_TYPE_SBUS: |
88 | __auxio_sbus_set_lte(on); |
89 | break; |
90 | case AUXIO_TYPE_EBUS: |
91 | default: |
92 | break; |
93 | } |
94 | } |
95 | EXPORT_SYMBOL(auxio_set_lte); |
96 | |
97 | static const struct of_device_id auxio_match[] = { |
98 | { |
99 | .name = "auxio" , |
100 | }, |
101 | {}, |
102 | }; |
103 | |
104 | MODULE_DEVICE_TABLE(of, auxio_match); |
105 | |
106 | static int auxio_probe(struct platform_device *dev) |
107 | { |
108 | struct device_node *dp = dev->dev.of_node; |
109 | unsigned long size; |
110 | |
111 | if (of_node_name_eq(np: dp->parent, name: "ebus" )) { |
112 | auxio_devtype = AUXIO_TYPE_EBUS; |
113 | size = sizeof(u32); |
114 | } else if (of_node_name_eq(np: dp->parent, name: "sbus" )) { |
115 | auxio_devtype = AUXIO_TYPE_SBUS; |
116 | size = 1; |
117 | } else { |
118 | printk("auxio: Unknown parent bus type [%pOFn]\n" , |
119 | dp->parent); |
120 | return -ENODEV; |
121 | } |
122 | auxio_register = of_ioremap(&dev->resource[0], 0, size, "auxio" ); |
123 | if (!auxio_register) |
124 | return -ENODEV; |
125 | |
126 | printk(KERN_INFO "AUXIO: Found device at %pOF\n" , dp); |
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 | |