xref: /linux/sound/isa/gus/gus_uart.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
1 /*
2  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
3  *  Routines for the GF1 MIDI interface - like UART 6850
4  *
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19  *
20  */
21 
22 #include <linux/delay.h>
23 #include <linux/interrupt.h>
24 #include <linux/time.h>
25 #include <sound/core.h>
26 #include <sound/gus.h>
27 
28 static void snd_gf1_interrupt_midi_in(struct snd_gus_card * gus)
29 {
30 	int count;
31 	unsigned char stat, data, byte;
32 	unsigned long flags;
33 
34 	count = 10;
35 	while (count) {
36 		spin_lock_irqsave(&gus->uart_cmd_lock, flags);
37 		stat = snd_gf1_uart_stat(gus);
38 		if (!(stat & 0x01)) {	/* data in Rx FIFO? */
39 			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
40 			count--;
41 			continue;
42 		}
43 		count = 100;	/* arm counter to new value */
44 		data = snd_gf1_uart_get(gus);
45 		if (!(gus->gf1.uart_cmd & 0x80)) {
46 			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
47 			continue;
48 		}
49 		if (stat & 0x10) {	/* framing error */
50 			gus->gf1.uart_framing++;
51 			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
52 			continue;
53 		}
54 		byte = snd_gf1_uart_get(gus);
55 		spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
56 		snd_rawmidi_receive(gus->midi_substream_input, &byte, 1);
57 		if (stat & 0x20) {
58 			gus->gf1.uart_overrun++;
59 		}
60 	}
61 }
62 
63 static void snd_gf1_interrupt_midi_out(struct snd_gus_card * gus)
64 {
65 	char byte;
66 	unsigned long flags;
67 
68 	/* try unlock output */
69 	if (snd_gf1_uart_stat(gus) & 0x01)
70 		snd_gf1_interrupt_midi_in(gus);
71 
72 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
73 	if (snd_gf1_uart_stat(gus) & 0x02) {	/* Tx FIFO free? */
74 		if (snd_rawmidi_transmit(gus->midi_substream_output, &byte, 1) != 1) {	/* no other bytes or error */
75 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x20); /* disable Tx interrupt */
76 		} else {
77 			snd_gf1_uart_put(gus, byte);
78 		}
79 	}
80 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
81 }
82 
83 static void snd_gf1_uart_reset(struct snd_gus_card * gus, int close)
84 {
85 	snd_gf1_uart_cmd(gus, 0x03);	/* reset */
86 	if (!close && gus->uart_enable) {
87 		udelay(160);
88 		snd_gf1_uart_cmd(gus, 0x00);	/* normal operations */
89 	}
90 }
91 
92 static int snd_gf1_uart_output_open(struct snd_rawmidi_substream *substream)
93 {
94 	unsigned long flags;
95 	struct snd_gus_card *gus;
96 
97 	gus = substream->rmidi->private_data;
98 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
99 	if (!(gus->gf1.uart_cmd & 0x80)) {	/* input active? */
100 		snd_gf1_uart_reset(gus, 0);
101 	}
102 	gus->gf1.interrupt_handler_midi_out = snd_gf1_interrupt_midi_out;
103 	gus->midi_substream_output = substream;
104 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
105 #if 0
106 	snd_printk(KERN_DEBUG "write init - cmd = 0x%x, stat = 0x%x\n", gus->gf1.uart_cmd, snd_gf1_uart_stat(gus));
107 #endif
108 	return 0;
109 }
110 
111 static int snd_gf1_uart_input_open(struct snd_rawmidi_substream *substream)
112 {
113 	unsigned long flags;
114 	struct snd_gus_card *gus;
115 	int i;
116 
117 	gus = substream->rmidi->private_data;
118 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
119 	if (gus->gf1.interrupt_handler_midi_out != snd_gf1_interrupt_midi_out) {
120 		snd_gf1_uart_reset(gus, 0);
121 	}
122 	gus->gf1.interrupt_handler_midi_in = snd_gf1_interrupt_midi_in;
123 	gus->midi_substream_input = substream;
124 	if (gus->uart_enable) {
125 		for (i = 0; i < 1000 && (snd_gf1_uart_stat(gus) & 0x01); i++)
126 			snd_gf1_uart_get(gus);	/* clean Rx */
127 		if (i >= 1000)
128 			snd_printk(KERN_ERR "gus midi uart init read - cleanup error\n");
129 	}
130 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
131 #if 0
132 	snd_printk("read init - enable = %i, cmd = 0x%x, stat = 0x%x\n", gus->uart_enable, gus->gf1.uart_cmd, snd_gf1_uart_stat(gus));
133 	snd_printk("[0x%x] reg (ctrl/status) = 0x%x, reg (data) = 0x%x (page = 0x%x)\n", gus->gf1.port + 0x100, inb(gus->gf1.port + 0x100), inb(gus->gf1.port + 0x101), inb(gus->gf1.port + 0x102));
134 #endif
135 	return 0;
136 }
137 
138 static int snd_gf1_uart_output_close(struct snd_rawmidi_substream *substream)
139 {
140 	unsigned long flags;
141 	struct snd_gus_card *gus;
142 
143 	gus = substream->rmidi->private_data;
144 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
145 	if (gus->gf1.interrupt_handler_midi_in != snd_gf1_interrupt_midi_in)
146 		snd_gf1_uart_reset(gus, 1);
147 	snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_MIDI_OUT);
148 	gus->midi_substream_output = NULL;
149 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
150 	return 0;
151 }
152 
153 static int snd_gf1_uart_input_close(struct snd_rawmidi_substream *substream)
154 {
155 	unsigned long flags;
156 	struct snd_gus_card *gus;
157 
158 	gus = substream->rmidi->private_data;
159 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
160 	if (gus->gf1.interrupt_handler_midi_out != snd_gf1_interrupt_midi_out)
161 		snd_gf1_uart_reset(gus, 1);
162 	snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_MIDI_IN);
163 	gus->midi_substream_input = NULL;
164 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
165 	return 0;
166 }
167 
168 static void snd_gf1_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
169 {
170 	struct snd_gus_card *gus;
171 	unsigned long flags;
172 
173 	gus = substream->rmidi->private_data;
174 
175 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
176 	if (up) {
177 		if ((gus->gf1.uart_cmd & 0x80) == 0)
178 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd | 0x80); /* enable Rx interrupts */
179 	} else {
180 		if (gus->gf1.uart_cmd & 0x80)
181 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x80); /* disable Rx interrupts */
182 	}
183 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
184 }
185 
186 static void snd_gf1_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
187 {
188 	unsigned long flags;
189 	struct snd_gus_card *gus;
190 	char byte;
191 	int timeout;
192 
193 	gus = substream->rmidi->private_data;
194 
195 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
196 	if (up) {
197 		if ((gus->gf1.uart_cmd & 0x20) == 0) {
198 			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
199 			/* wait for empty Rx - Tx is probably unlocked */
200 			timeout = 10000;
201 			while (timeout-- > 0 && snd_gf1_uart_stat(gus) & 0x01);
202 			/* Tx FIFO free? */
203 			spin_lock_irqsave(&gus->uart_cmd_lock, flags);
204 			if (gus->gf1.uart_cmd & 0x20) {
205 				spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
206 				return;
207 			}
208 			if (snd_gf1_uart_stat(gus) & 0x02) {
209 				if (snd_rawmidi_transmit(substream, &byte, 1) != 1) {
210 					spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
211 					return;
212 				}
213 				snd_gf1_uart_put(gus, byte);
214 			}
215 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd | 0x20);	/* enable Tx interrupt */
216 		}
217 	} else {
218 		if (gus->gf1.uart_cmd & 0x20)
219 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x20);
220 	}
221 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
222 }
223 
224 static struct snd_rawmidi_ops snd_gf1_uart_output =
225 {
226 	.open =		snd_gf1_uart_output_open,
227 	.close =	snd_gf1_uart_output_close,
228 	.trigger =	snd_gf1_uart_output_trigger,
229 };
230 
231 static struct snd_rawmidi_ops snd_gf1_uart_input =
232 {
233 	.open =		snd_gf1_uart_input_open,
234 	.close =	snd_gf1_uart_input_close,
235 	.trigger =	snd_gf1_uart_input_trigger,
236 };
237 
238 int snd_gf1_rawmidi_new(struct snd_gus_card * gus, int device, struct snd_rawmidi ** rrawmidi)
239 {
240 	struct snd_rawmidi *rmidi;
241 	int err;
242 
243 	if (rrawmidi)
244 		*rrawmidi = NULL;
245 	if ((err = snd_rawmidi_new(gus->card, "GF1", device, 1, 1, &rmidi)) < 0)
246 		return err;
247 	strcpy(rmidi->name, gus->interwave ? "AMD InterWave" : "GF1");
248 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_gf1_uart_output);
249 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_gf1_uart_input);
250 	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT | SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX;
251 	rmidi->private_data = gus;
252 	gus->midi_uart = rmidi;
253 	if (rrawmidi)
254 		*rrawmidi = rmidi;
255 	return err;
256 }
257