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 #ifdef DEBUG
32 #define DPRINTK printk
33 #else
34 #define DPRINTK(x...) do { } while (0)
35 #endif
36
37
amiga_write_data(struct parport * p,unsigned char data)38 static void amiga_write_data(struct parport *p, unsigned char data)
39 {
40 DPRINTK(KERN_DEBUG "write_data %c\n",data);
41 /* Triggers also /STROBE. This behavior cannot be changed */
42 ciaa.prb = data;
43 mb();
44 }
45
amiga_read_data(struct parport * p)46 static unsigned char amiga_read_data(struct parport *p)
47 {
48 /* Triggers also /STROBE. This behavior cannot be changed */
49 return ciaa.prb;
50 }
51
control_amiga_to_pc(unsigned char control)52 static unsigned char control_amiga_to_pc(unsigned char control)
53 {
54 return PARPORT_CONTROL_SELECT |
55 PARPORT_CONTROL_AUTOFD | PARPORT_CONTROL_STROBE;
56 /* fake value: interrupt enable, select in, no reset,
57 no autolf, no strobe - seems to be closest the wiring diagram */
58 }
59
amiga_write_control(struct parport * p,unsigned char control)60 static void amiga_write_control(struct parport *p, unsigned char control)
61 {
62 DPRINTK(KERN_DEBUG "write_control %02x\n",control);
63 /* No implementation possible */
64 }
65
amiga_read_control(struct parport * p)66 static unsigned char amiga_read_control( struct parport *p)
67 {
68 DPRINTK(KERN_DEBUG "read_control \n");
69 return control_amiga_to_pc(0);
70 }
71
amiga_frob_control(struct parport * p,unsigned char mask,unsigned char val)72 static unsigned char amiga_frob_control( struct parport *p, unsigned char mask, unsigned char val)
73 {
74 unsigned char old;
75
76 DPRINTK(KERN_DEBUG "frob_control mask %02x, value %02x\n",mask,val);
77 old = amiga_read_control(p);
78 amiga_write_control(p, (old & ~mask) ^ val);
79 return old;
80 }
81
status_amiga_to_pc(unsigned char status)82 static unsigned char status_amiga_to_pc(unsigned char status)
83 {
84 unsigned char ret = PARPORT_STATUS_BUSY | PARPORT_STATUS_ACK | PARPORT_STATUS_ERROR;
85
86 if (status & 1) /* Busy */
87 ret &= ~PARPORT_STATUS_BUSY;
88 if (status & 2) /* PaperOut */
89 ret |= PARPORT_STATUS_PAPEROUT;
90 if (status & 4) /* Selected */
91 ret |= PARPORT_STATUS_SELECT;
92 /* the rest is not connected or handled autonomously in hardware */
93
94 return ret;
95 }
96
amiga_read_status(struct parport * p)97 static unsigned char amiga_read_status(struct parport *p)
98 {
99 unsigned char status;
100
101 status = status_amiga_to_pc(ciab.pra & 7);
102 DPRINTK(KERN_DEBUG "read_status %02x\n", status);
103 return status;
104 }
105
amiga_enable_irq(struct parport * p)106 static void amiga_enable_irq(struct parport *p)
107 {
108 enable_irq(IRQ_AMIGA_CIAA_FLG);
109 }
110
amiga_disable_irq(struct parport * p)111 static void amiga_disable_irq(struct parport *p)
112 {
113 disable_irq(IRQ_AMIGA_CIAA_FLG);
114 }
115
amiga_data_forward(struct parport * p)116 static void amiga_data_forward(struct parport *p)
117 {
118 DPRINTK(KERN_DEBUG "forward\n");
119 ciaa.ddrb = 0xff; /* all pins output */
120 mb();
121 }
122
amiga_data_reverse(struct parport * p)123 static void amiga_data_reverse(struct parport *p)
124 {
125 DPRINTK(KERN_DEBUG "reverse\n");
126 ciaa.ddrb = 0; /* all pins input */
127 mb();
128 }
129
amiga_init_state(struct pardevice * dev,struct parport_state * s)130 static void amiga_init_state(struct pardevice *dev, struct parport_state *s)
131 {
132 s->u.amiga.data = 0;
133 s->u.amiga.datadir = 255;
134 s->u.amiga.status = 0;
135 s->u.amiga.statusdir = 0;
136 }
137
amiga_save_state(struct parport * p,struct parport_state * s)138 static void amiga_save_state(struct parport *p, struct parport_state *s)
139 {
140 mb();
141 s->u.amiga.data = ciaa.prb;
142 s->u.amiga.datadir = ciaa.ddrb;
143 s->u.amiga.status = ciab.pra & 7;
144 s->u.amiga.statusdir = ciab.ddra & 7;
145 mb();
146 }
147
amiga_restore_state(struct parport * p,struct parport_state * s)148 static void amiga_restore_state(struct parport *p, struct parport_state *s)
149 {
150 mb();
151 ciaa.prb = s->u.amiga.data;
152 ciaa.ddrb = s->u.amiga.datadir;
153 ciab.pra |= (ciab.pra & 0xf8) | s->u.amiga.status;
154 ciab.ddra |= (ciab.ddra & 0xf8) | s->u.amiga.statusdir;
155 mb();
156 }
157
158 static struct parport_operations pp_amiga_ops = {
159 .write_data = amiga_write_data,
160 .read_data = amiga_read_data,
161
162 .write_control = amiga_write_control,
163 .read_control = amiga_read_control,
164 .frob_control = amiga_frob_control,
165
166 .read_status = amiga_read_status,
167
168 .enable_irq = amiga_enable_irq,
169 .disable_irq = amiga_disable_irq,
170
171 .data_forward = amiga_data_forward,
172 .data_reverse = amiga_data_reverse,
173
174 .init_state = amiga_init_state,
175 .save_state = amiga_save_state,
176 .restore_state = amiga_restore_state,
177
178 .epp_write_data = parport_ieee1284_epp_write_data,
179 .epp_read_data = parport_ieee1284_epp_read_data,
180 .epp_write_addr = parport_ieee1284_epp_write_addr,
181 .epp_read_addr = parport_ieee1284_epp_read_addr,
182
183 .ecp_write_data = parport_ieee1284_ecp_write_data,
184 .ecp_read_data = parport_ieee1284_ecp_read_data,
185 .ecp_write_addr = parport_ieee1284_ecp_write_addr,
186
187 .compat_write_data = parport_ieee1284_write_compat,
188 .nibble_read_data = parport_ieee1284_read_nibble,
189 .byte_read_data = parport_ieee1284_read_byte,
190
191 .owner = THIS_MODULE,
192 };
193
194 /* ----------- Initialisation code --------------------------------- */
195
amiga_parallel_probe(struct platform_device * pdev)196 static int __init amiga_parallel_probe(struct platform_device *pdev)
197 {
198 struct parport *p;
199 int err;
200
201 ciaa.ddrb = 0xff;
202 ciab.ddra &= 0xf8;
203 mb();
204
205 p = parport_register_port((unsigned long)&ciaa.prb, IRQ_AMIGA_CIAA_FLG,
206 PARPORT_DMA_NONE, &pp_amiga_ops);
207 if (!p)
208 return -EBUSY;
209
210 err = request_irq(IRQ_AMIGA_CIAA_FLG, parport_irq_handler, 0, p->name,
211 p);
212 if (err)
213 goto out_irq;
214
215 printk(KERN_INFO "%s: Amiga built-in port using irq\n", p->name);
216 /* XXX: set operating mode */
217 parport_announce_port(p);
218
219 platform_set_drvdata(pdev, p);
220
221 return 0;
222
223 out_irq:
224 parport_put_port(p);
225 return err;
226 }
227
amiga_parallel_remove(struct platform_device * pdev)228 static int __exit amiga_parallel_remove(struct platform_device *pdev)
229 {
230 struct parport *port = platform_get_drvdata(pdev);
231
232 parport_remove_port(port);
233 if (port->irq != PARPORT_IRQ_NONE)
234 free_irq(IRQ_AMIGA_CIAA_FLG, port);
235 parport_put_port(port);
236 return 0;
237 }
238
239 static struct platform_driver amiga_parallel_driver = {
240 .remove = __exit_p(amiga_parallel_remove),
241 .driver = {
242 .name = "amiga-parallel",
243 },
244 };
245
246 module_platform_driver_probe(amiga_parallel_driver, amiga_parallel_probe);
247
248 MODULE_AUTHOR("Joerg Dorchain <joerg@dorchain.net>");
249 MODULE_DESCRIPTION("Parport Driver for Amiga builtin Port");
250 MODULE_SUPPORTED_DEVICE("Amiga builtin Parallel Port");
251 MODULE_LICENSE("GPL");
252 MODULE_ALIAS("platform:amiga-parallel");
253