xref: /linux/drivers/parport/parport_amiga.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
1 /* Low-level parallel port routines for the Amiga built-in port
2  *
3  * Author: Joerg Dorchain <joerg@dorchain.net>
4  *
5  * This is a complete rewrite of the code, but based heaviy upon the old
6  * lp_intern. code.
7  *
8  * The built-in Amiga parallel port provides one port at a fixed address
9  * with 8 bidirectional data lines (D0 - D7) and 3 bidirectional status
10  * lines (BUSY, POUT, SEL), 1 output control line /STROBE (raised automatically
11  * in hardware when the data register is accessed), and 1 input control line
12  * /ACK, able to cause an interrupt, but both not directly settable by
13  * software.
14  */
15 
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/parport.h>
19 #include <linux/ioport.h>
20 #include <linux/interrupt.h>
21 #include <linux/platform_device.h>
22 
23 #include <asm/setup.h>
24 #include <asm/amigahw.h>
25 #include <asm/irq.h>
26 #include <asm/io.h>
27 #include <asm/amigaints.h>
28 
29 #undef DEBUG
30 #ifdef DEBUG
31 #define DPRINTK printk
32 #else
33 #define DPRINTK(x...)	do { } while (0)
34 #endif
35 
36 
37 static void amiga_write_data(struct parport *p, unsigned char data)
38 {
39 	DPRINTK(KERN_DEBUG "write_data %c\n",data);
40 	/* Triggers also /STROBE. This behavior cannot be changed */
41 	ciaa.prb = data;
42 	mb();
43 }
44 
45 static unsigned char amiga_read_data(struct parport *p)
46 {
47 	/* Triggers also /STROBE. This behavior cannot be changed */
48 	return ciaa.prb;
49 }
50 
51 static unsigned char control_amiga_to_pc(unsigned char control)
52 {
53 	return PARPORT_CONTROL_SELECT |
54 	      PARPORT_CONTROL_AUTOFD | PARPORT_CONTROL_STROBE;
55 	/* fake value: interrupt enable, select in, no reset,
56 	no autolf, no strobe - seems to be closest the wiring diagram */
57 }
58 
59 static void amiga_write_control(struct parport *p, unsigned char control)
60 {
61 	DPRINTK(KERN_DEBUG "write_control %02x\n",control);
62 	/* No implementation possible */
63 }
64 
65 static unsigned char amiga_read_control( struct parport *p)
66 {
67 	DPRINTK(KERN_DEBUG "read_control \n");
68 	return control_amiga_to_pc(0);
69 }
70 
71 static unsigned char amiga_frob_control( struct parport *p, unsigned char mask, unsigned char val)
72 {
73 	unsigned char old;
74 
75 	DPRINTK(KERN_DEBUG "frob_control mask %02x, value %02x\n",mask,val);
76 	old = amiga_read_control(p);
77 	amiga_write_control(p, (old & ~mask) ^ val);
78 	return old;
79 }
80 
81 static unsigned char status_amiga_to_pc(unsigned char status)
82 {
83 	unsigned char ret = PARPORT_STATUS_BUSY | PARPORT_STATUS_ACK | PARPORT_STATUS_ERROR;
84 
85 	if (status & 1) /* Busy */
86 		ret &= ~PARPORT_STATUS_BUSY;
87 	if (status & 2) /* PaperOut */
88 		ret |= PARPORT_STATUS_PAPEROUT;
89 	if (status & 4) /* Selected */
90 		ret |= PARPORT_STATUS_SELECT;
91 	/* the rest is not connected or handled autonomously in hardware */
92 
93 	return ret;
94 }
95 
96 static unsigned char amiga_read_status(struct parport *p)
97 {
98 	unsigned char status;
99 
100 	status = status_amiga_to_pc(ciab.pra & 7);
101 	DPRINTK(KERN_DEBUG "read_status %02x\n", status);
102 	return status;
103 }
104 
105 static void amiga_enable_irq(struct parport *p)
106 {
107 	enable_irq(IRQ_AMIGA_CIAA_FLG);
108 }
109 
110 static void amiga_disable_irq(struct parport *p)
111 {
112 	disable_irq(IRQ_AMIGA_CIAA_FLG);
113 }
114 
115 static void amiga_data_forward(struct parport *p)
116 {
117 	DPRINTK(KERN_DEBUG "forward\n");
118 	ciaa.ddrb = 0xff; /* all pins output */
119 	mb();
120 }
121 
122 static void amiga_data_reverse(struct parport *p)
123 {
124 	DPRINTK(KERN_DEBUG "reverse\n");
125 	ciaa.ddrb = 0; /* all pins input */
126 	mb();
127 }
128 
129 static void amiga_init_state(struct pardevice *dev, struct parport_state *s)
130 {
131 	s->u.amiga.data = 0;
132 	s->u.amiga.datadir = 255;
133 	s->u.amiga.status = 0;
134 	s->u.amiga.statusdir = 0;
135 }
136 
137 static void amiga_save_state(struct parport *p, struct parport_state *s)
138 {
139 	mb();
140 	s->u.amiga.data = ciaa.prb;
141 	s->u.amiga.datadir = ciaa.ddrb;
142 	s->u.amiga.status = ciab.pra & 7;
143 	s->u.amiga.statusdir = ciab.ddra & 7;
144 	mb();
145 }
146 
147 static void amiga_restore_state(struct parport *p, struct parport_state *s)
148 {
149 	mb();
150 	ciaa.prb = s->u.amiga.data;
151 	ciaa.ddrb = s->u.amiga.datadir;
152 	ciab.pra |= (ciab.pra & 0xf8) | s->u.amiga.status;
153 	ciab.ddra |= (ciab.ddra & 0xf8) | s->u.amiga.statusdir;
154 	mb();
155 }
156 
157 static struct parport_operations pp_amiga_ops = {
158 	.write_data	= amiga_write_data,
159 	.read_data	= amiga_read_data,
160 
161 	.write_control	= amiga_write_control,
162 	.read_control	= amiga_read_control,
163 	.frob_control	= amiga_frob_control,
164 
165 	.read_status	= amiga_read_status,
166 
167 	.enable_irq	= amiga_enable_irq,
168 	.disable_irq	= amiga_disable_irq,
169 
170 	.data_forward	= amiga_data_forward,
171 	.data_reverse	= amiga_data_reverse,
172 
173 	.init_state	= amiga_init_state,
174 	.save_state	= amiga_save_state,
175 	.restore_state	= amiga_restore_state,
176 
177 	.epp_write_data	= parport_ieee1284_epp_write_data,
178 	.epp_read_data	= parport_ieee1284_epp_read_data,
179 	.epp_write_addr	= parport_ieee1284_epp_write_addr,
180 	.epp_read_addr	= parport_ieee1284_epp_read_addr,
181 
182 	.ecp_write_data	= parport_ieee1284_ecp_write_data,
183 	.ecp_read_data	= parport_ieee1284_ecp_read_data,
184 	.ecp_write_addr	= parport_ieee1284_ecp_write_addr,
185 
186 	.compat_write_data	= parport_ieee1284_write_compat,
187 	.nibble_read_data	= parport_ieee1284_read_nibble,
188 	.byte_read_data		= parport_ieee1284_read_byte,
189 
190 	.owner		= THIS_MODULE,
191 };
192 
193 /* ----------- Initialisation code --------------------------------- */
194 
195 static int __init amiga_parallel_probe(struct platform_device *pdev)
196 {
197 	struct parport *p;
198 	int err;
199 
200 	ciaa.ddrb = 0xff;
201 	ciab.ddra &= 0xf8;
202 	mb();
203 
204 	p = parport_register_port((unsigned long)&ciaa.prb, IRQ_AMIGA_CIAA_FLG,
205 				   PARPORT_DMA_NONE, &pp_amiga_ops);
206 	if (!p)
207 		return -EBUSY;
208 
209 	err = request_irq(IRQ_AMIGA_CIAA_FLG, parport_irq_handler, 0, p->name,
210 			  p);
211 	if (err)
212 		goto out_irq;
213 
214 	printk(KERN_INFO "%s: Amiga built-in port using irq\n", p->name);
215 	/* XXX: set operating mode */
216 	parport_announce_port(p);
217 
218 	platform_set_drvdata(pdev, p);
219 
220 	return 0;
221 
222 out_irq:
223 	parport_put_port(p);
224 	return err;
225 }
226 
227 static int __exit amiga_parallel_remove(struct platform_device *pdev)
228 {
229 	struct parport *port = platform_get_drvdata(pdev);
230 
231 	parport_remove_port(port);
232 	if (port->irq != PARPORT_IRQ_NONE)
233 		free_irq(IRQ_AMIGA_CIAA_FLG, port);
234 	parport_put_port(port);
235 	return 0;
236 }
237 
238 static struct platform_driver amiga_parallel_driver = {
239 	.remove = __exit_p(amiga_parallel_remove),
240 	.driver   = {
241 		.name	= "amiga-parallel",
242 		.owner	= THIS_MODULE,
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