1 /* Low-level parallel port routines for Archimedes onboard hardware
2 *
3 * Author: Phil Blundell <Philip.Blundell@pobox.com>
4 */
5
6 /* This driver is for the parallel port hardware found on Acorn's old
7 * range of Archimedes machines. The A5000 and newer systems have PC-style
8 * I/O hardware and should use the parport_pc driver instead.
9 *
10 * The Acorn printer port hardware is very simple. There is a single 8-bit
11 * write-only latch for the data port and control/status bits are handled
12 * with various auxilliary input and output lines. The port is not
13 * bidirectional, does not support any modes other than SPP, and has only
14 * a subset of the standard printer control lines connected.
15 */
16
17 #include <linux/threads.h>
18 #include <linux/delay.h>
19 #include <linux/errno.h>
20 #include <linux/interrupt.h>
21 #include <linux/ioport.h>
22 #include <linux/kernel.h>
23 #include <linux/malloc.h>
24 #include <linux/parport.h>
25
26 #include <asm/ptrace.h>
27 #include <asm/io.h>
28 #include <asm/arch/oldlatches.h>
29 #include <asm/arch/irqs.h>
30
31 #define DATA_ADDRESS 0x3350010
32
33 /* This is equivalent to the above and only used for request_region. */
34 #define PORT_BASE 0x80000000 | ((DATA_ADDRESS - IO_BASE) >> 2)
35
36 /* The hardware can't read from the data latch, so we must use a soft
37 copy. */
38 static unsigned char data_copy;
39
40 /* These are pretty simple. We know the irq is never shared and the
41 kernel does all the magic that's required. */
42 static void arc_enable_irq(struct parport *p)
43 {
44 enable_irq(p->irq);
45 }
46
47 static void arc_disable_irq(struct parport *p)
48 {
49 disable_irq(p->irq);
50 }
51
52 static void arc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
53 {
54 parport_generic_irq(irq, (struct parport *) dev_id, regs);
55 }
56
57 static void arc_write_data(struct parport *p, unsigned char data)
58 {
59 data_copy = data;
60 outb_t(data, DATA_LATCH);
61 }
62
63 static unsigned char arc_read_data(struct parport *p)
64 {
65 return data_copy;
66 }
67
68 static void arc_inc_use_count(void)
69 {
70 #ifdef MODULE
71 MOD_INC_USE_COUNT;
72 #endif
73 }
74
75 static void arc_dec_use_count(void)
76 {
77 #ifdef MODULE
78 MOD_DEC_USE_COUNT;
79 #endif
80 }
81
82 static struct parport_operations parport_arc_ops =
83 {
84 arc_write_data,
85 arc_read_data,
86
87 arc_write_control,
88 arc_read_control,
89 arc_frob_control,
90
91 arc_read_status,
92
93 arc_enable_irq,
94 arc_disable_irq,
95
96 arc_data_forward,
97 arc_data_reverse,
98
99 arc_init_state,
100 arc_save_state,
101 arc_restore_state,
102
103 arc_inc_use_count,
104 arc_dec_use_count,
105
106 parport_ieee1284_epp_write_data,
107 parport_ieee1284_epp_read_data,
108 parport_ieee1284_epp_write_addr,
109 parport_ieee1284_epp_read_addr,
110
111 parport_ieee1284_ecp_write_data,
112 parport_ieee1284_ecp_read_data,
113 parport_ieee1284_ecp_write_addr,
114
115 parport_ieee1284_write_compat,
116 parport_ieee1284_read_nibble,
117 parport_ieee1284_read_byte,
118 };
119
120 /* --- Initialisation code -------------------------------- */
121
122 int parport_arc_init(void)
123 {
124 /* Archimedes hardware provides only one port, at a fixed address */
125 struct parport *p;
126
127 if (check_region(PORT_BASE, 1))
128 return 0;
129
130 p = parport_register_port (PORT_BASE, IRQ_PRINTERACK,
131 PARPORT_DMA_NONE, &parport_arc_ops);
132
133 if (!p)
134 return 0;
135
136 p->modes = PARPORT_MODE_ARCSPP;
137 p->size = 1;
138
139 printk(KERN_INFO "%s: Archimedes on-board port, using irq %d\n",
140 p->irq);
141 parport_proc_register(p);
142
143 /* Tell the high-level drivers about the port. */
144 parport_announce_port (p);
145
146 return 1;
147 }
148
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