1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* Low-level parallel port routines for the Amiga built-in port |
3 | * |
4 | * Author: Joerg Dorchain <joerg@dorchain.net> |
5 | * |
6 | * This is a complete rewrite of the code, but based heaviy upon the old |
7 | * lp_intern. code. |
8 | * |
9 | * The built-in Amiga parallel port provides one port at a fixed address |
10 | * with 8 bidirectional data lines (D0 - D7) and 3 bidirectional status |
11 | * lines (BUSY, POUT, SEL), 1 output control line /STROBE (raised automatically |
12 | * in hardware when the data register is accessed), and 1 input control line |
13 | * /ACK, able to cause an interrupt, but both not directly settable by |
14 | * software. |
15 | */ |
16 | |
17 | #include <linux/module.h> |
18 | #include <linux/init.h> |
19 | #include <linux/parport.h> |
20 | #include <linux/ioport.h> |
21 | #include <linux/interrupt.h> |
22 | #include <linux/platform_device.h> |
23 | |
24 | #include <asm/setup.h> |
25 | #include <asm/amigahw.h> |
26 | #include <asm/irq.h> |
27 | #include <asm/io.h> |
28 | #include <asm/amigaints.h> |
29 | |
30 | #undef DEBUG |
31 | |
32 | static void amiga_write_data(struct parport *p, unsigned char data) |
33 | { |
34 | pr_debug("write_data %c\n" , data); |
35 | /* Triggers also /STROBE. This behavior cannot be changed */ |
36 | ciaa.prb = data; |
37 | mb(); |
38 | } |
39 | |
40 | static unsigned char amiga_read_data(struct parport *p) |
41 | { |
42 | /* Triggers also /STROBE. This behavior cannot be changed */ |
43 | return ciaa.prb; |
44 | } |
45 | |
46 | static unsigned char control_amiga_to_pc(unsigned char control) |
47 | { |
48 | return PARPORT_CONTROL_SELECT | |
49 | PARPORT_CONTROL_AUTOFD | PARPORT_CONTROL_STROBE; |
50 | /* fake value: interrupt enable, select in, no reset, |
51 | no autolf, no strobe - seems to be closest the wiring diagram */ |
52 | } |
53 | |
54 | static void amiga_write_control(struct parport *p, unsigned char control) |
55 | { |
56 | pr_debug("write_control %02x\n" , control); |
57 | /* No implementation possible */ |
58 | } |
59 | |
60 | static unsigned char amiga_read_control( struct parport *p) |
61 | { |
62 | pr_debug("read_control\n" ); |
63 | return control_amiga_to_pc(control: 0); |
64 | } |
65 | |
66 | static unsigned char amiga_frob_control( struct parport *p, unsigned char mask, unsigned char val) |
67 | { |
68 | unsigned char old; |
69 | |
70 | pr_debug("frob_control mask %02x, value %02x\n" , mask, val); |
71 | old = amiga_read_control(p); |
72 | amiga_write_control(p, control: (old & ~mask) ^ val); |
73 | return old; |
74 | } |
75 | |
76 | static unsigned char status_amiga_to_pc(unsigned char status) |
77 | { |
78 | unsigned char ret = PARPORT_STATUS_BUSY | PARPORT_STATUS_ACK | PARPORT_STATUS_ERROR; |
79 | |
80 | if (status & 1) /* Busy */ |
81 | ret &= ~PARPORT_STATUS_BUSY; |
82 | if (status & 2) /* PaperOut */ |
83 | ret |= PARPORT_STATUS_PAPEROUT; |
84 | if (status & 4) /* Selected */ |
85 | ret |= PARPORT_STATUS_SELECT; |
86 | /* the rest is not connected or handled autonomously in hardware */ |
87 | |
88 | return ret; |
89 | } |
90 | |
91 | static unsigned char amiga_read_status(struct parport *p) |
92 | { |
93 | unsigned char status; |
94 | |
95 | status = status_amiga_to_pc(status: ciab.pra & 7); |
96 | pr_debug("read_status %02x\n" , status); |
97 | return status; |
98 | } |
99 | |
100 | static void amiga_enable_irq(struct parport *p) |
101 | { |
102 | enable_irq(irq: IRQ_AMIGA_CIAA_FLG); |
103 | } |
104 | |
105 | static void amiga_disable_irq(struct parport *p) |
106 | { |
107 | disable_irq(irq: IRQ_AMIGA_CIAA_FLG); |
108 | } |
109 | |
110 | static void amiga_data_forward(struct parport *p) |
111 | { |
112 | pr_debug("forward\n" ); |
113 | ciaa.ddrb = 0xff; /* all pins output */ |
114 | mb(); |
115 | } |
116 | |
117 | static void amiga_data_reverse(struct parport *p) |
118 | { |
119 | pr_debug("reverse\n" ); |
120 | ciaa.ddrb = 0; /* all pins input */ |
121 | mb(); |
122 | } |
123 | |
124 | static void amiga_init_state(struct pardevice *dev, struct parport_state *s) |
125 | { |
126 | s->u.amiga.data = 0; |
127 | s->u.amiga.datadir = 255; |
128 | s->u.amiga.status = 0; |
129 | s->u.amiga.statusdir = 0; |
130 | } |
131 | |
132 | static void amiga_save_state(struct parport *p, struct parport_state *s) |
133 | { |
134 | mb(); |
135 | s->u.amiga.data = ciaa.prb; |
136 | s->u.amiga.datadir = ciaa.ddrb; |
137 | s->u.amiga.status = ciab.pra & 7; |
138 | s->u.amiga.statusdir = ciab.ddra & 7; |
139 | mb(); |
140 | } |
141 | |
142 | static void amiga_restore_state(struct parport *p, struct parport_state *s) |
143 | { |
144 | mb(); |
145 | ciaa.prb = s->u.amiga.data; |
146 | ciaa.ddrb = s->u.amiga.datadir; |
147 | ciab.pra |= (ciab.pra & 0xf8) | s->u.amiga.status; |
148 | ciab.ddra |= (ciab.ddra & 0xf8) | s->u.amiga.statusdir; |
149 | mb(); |
150 | } |
151 | |
152 | static struct parport_operations pp_amiga_ops = { |
153 | .write_data = amiga_write_data, |
154 | .read_data = amiga_read_data, |
155 | |
156 | .write_control = amiga_write_control, |
157 | .read_control = amiga_read_control, |
158 | .frob_control = amiga_frob_control, |
159 | |
160 | .read_status = amiga_read_status, |
161 | |
162 | .enable_irq = amiga_enable_irq, |
163 | .disable_irq = amiga_disable_irq, |
164 | |
165 | .data_forward = amiga_data_forward, |
166 | .data_reverse = amiga_data_reverse, |
167 | |
168 | .init_state = amiga_init_state, |
169 | .save_state = amiga_save_state, |
170 | .restore_state = amiga_restore_state, |
171 | |
172 | .epp_write_data = parport_ieee1284_epp_write_data, |
173 | .epp_read_data = parport_ieee1284_epp_read_data, |
174 | .epp_write_addr = parport_ieee1284_epp_write_addr, |
175 | .epp_read_addr = parport_ieee1284_epp_read_addr, |
176 | |
177 | .ecp_write_data = parport_ieee1284_ecp_write_data, |
178 | .ecp_read_data = parport_ieee1284_ecp_read_data, |
179 | .ecp_write_addr = parport_ieee1284_ecp_write_addr, |
180 | |
181 | .compat_write_data = parport_ieee1284_write_compat, |
182 | .nibble_read_data = parport_ieee1284_read_nibble, |
183 | .byte_read_data = parport_ieee1284_read_byte, |
184 | |
185 | .owner = THIS_MODULE, |
186 | }; |
187 | |
188 | /* ----------- Initialisation code --------------------------------- */ |
189 | |
190 | static int __init amiga_parallel_probe(struct platform_device *pdev) |
191 | { |
192 | struct parport *p; |
193 | int err; |
194 | |
195 | ciaa.ddrb = 0xff; |
196 | ciab.ddra &= 0xf8; |
197 | mb(); |
198 | |
199 | p = parport_register_port((unsigned long)&ciaa.prb, IRQ_AMIGA_CIAA_FLG, |
200 | PARPORT_DMA_NONE, &pp_amiga_ops); |
201 | if (!p) |
202 | return -EBUSY; |
203 | |
204 | err = request_irq(irq: IRQ_AMIGA_CIAA_FLG, handler: parport_irq_handler, flags: 0, name: p->name, |
205 | dev: p); |
206 | if (err) |
207 | goto out_irq; |
208 | |
209 | pr_info("%s: Amiga built-in port using irq\n" , p->name); |
210 | /* XXX: set operating mode */ |
211 | parport_announce_port(port: p); |
212 | |
213 | platform_set_drvdata(pdev, data: p); |
214 | |
215 | return 0; |
216 | |
217 | out_irq: |
218 | parport_put_port(p); |
219 | return err; |
220 | } |
221 | |
222 | static int __exit amiga_parallel_remove(struct platform_device *pdev) |
223 | { |
224 | struct parport *port = platform_get_drvdata(pdev); |
225 | |
226 | parport_remove_port(port); |
227 | if (port->irq != PARPORT_IRQ_NONE) |
228 | free_irq(IRQ_AMIGA_CIAA_FLG, port); |
229 | parport_put_port(port); |
230 | return 0; |
231 | } |
232 | |
233 | static struct platform_driver amiga_parallel_driver = { |
234 | .remove = __exit_p(amiga_parallel_remove), |
235 | .driver = { |
236 | .name = "amiga-parallel" , |
237 | }, |
238 | }; |
239 | |
240 | module_platform_driver_probe(amiga_parallel_driver, amiga_parallel_probe); |
241 | |
242 | MODULE_AUTHOR("Joerg Dorchain <joerg@dorchain.net>" ); |
243 | MODULE_DESCRIPTION("Parport Driver for Amiga builtin Port" ); |
244 | MODULE_LICENSE("GPL" ); |
245 | MODULE_ALIAS("platform:amiga-parallel" ); |
246 | |