xref: /openbmc/linux/sound/isa/gus/gus_uart.c (revision 64c70b1c)
1 /*
2  *  Copyright (c) by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
23 #include <linux/delay.h>
24 #include <linux/interrupt.h>
25 #include <linux/time.h>
26 #include <sound/core.h>
27 #include <sound/gus.h>
28 
29 static void snd_gf1_interrupt_midi_in(struct snd_gus_card * gus)
30 {
31 	int count;
32 	unsigned char stat, data, byte;
33 	unsigned long flags;
34 
35 	count = 10;
36 	while (count) {
37 		spin_lock_irqsave(&gus->uart_cmd_lock, flags);
38 		stat = snd_gf1_uart_stat(gus);
39 		if (!(stat & 0x01)) {	/* data in Rx FIFO? */
40 			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
41 			count--;
42 			continue;
43 		}
44 		count = 100;	/* arm counter to new value */
45 		data = snd_gf1_uart_get(gus);
46 		if (!(gus->gf1.uart_cmd & 0x80)) {
47 			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
48 			continue;
49 		}
50 		if (stat & 0x10) {	/* framing error */
51 			gus->gf1.uart_framing++;
52 			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
53 			continue;
54 		}
55 		byte = snd_gf1_uart_get(gus);
56 		spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
57 		snd_rawmidi_receive(gus->midi_substream_input, &byte, 1);
58 		if (stat & 0x20) {
59 			gus->gf1.uart_overrun++;
60 		}
61 	}
62 }
63 
64 static void snd_gf1_interrupt_midi_out(struct snd_gus_card * gus)
65 {
66 	char byte;
67 	unsigned long flags;
68 
69 	/* try unlock output */
70 	if (snd_gf1_uart_stat(gus) & 0x01)
71 		snd_gf1_interrupt_midi_in(gus);
72 
73 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
74 	if (snd_gf1_uart_stat(gus) & 0x02) {	/* Tx FIFO free? */
75 		if (snd_rawmidi_transmit(gus->midi_substream_output, &byte, 1) != 1) {	/* no other bytes or error */
76 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x20); /* disable Tx interrupt */
77 		} else {
78 			snd_gf1_uart_put(gus, byte);
79 		}
80 	}
81 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
82 }
83 
84 static void snd_gf1_uart_reset(struct snd_gus_card * gus, int close)
85 {
86 	snd_gf1_uart_cmd(gus, 0x03);	/* reset */
87 	if (!close && gus->uart_enable) {
88 		udelay(160);
89 		snd_gf1_uart_cmd(gus, 0x00);	/* normal operations */
90 	}
91 }
92 
93 static int snd_gf1_uart_output_open(struct snd_rawmidi_substream *substream)
94 {
95 	unsigned long flags;
96 	struct snd_gus_card *gus;
97 
98 	gus = substream->rmidi->private_data;
99 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
100 	if (!(gus->gf1.uart_cmd & 0x80)) {	/* input active? */
101 		snd_gf1_uart_reset(gus, 0);
102 	}
103 	gus->gf1.interrupt_handler_midi_out = snd_gf1_interrupt_midi_out;
104 	gus->midi_substream_output = substream;
105 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
106 #if 0
107 	snd_printk(KERN_DEBUG "write init - cmd = 0x%x, stat = 0x%x\n", gus->gf1.uart_cmd, snd_gf1_uart_stat(gus));
108 #endif
109 	return 0;
110 }
111 
112 static int snd_gf1_uart_input_open(struct snd_rawmidi_substream *substream)
113 {
114 	unsigned long flags;
115 	struct snd_gus_card *gus;
116 	int i;
117 
118 	gus = substream->rmidi->private_data;
119 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
120 	if (gus->gf1.interrupt_handler_midi_out != snd_gf1_interrupt_midi_out) {
121 		snd_gf1_uart_reset(gus, 0);
122 	}
123 	gus->gf1.interrupt_handler_midi_in = snd_gf1_interrupt_midi_in;
124 	gus->midi_substream_input = substream;
125 	if (gus->uart_enable) {
126 		for (i = 0; i < 1000 && (snd_gf1_uart_stat(gus) & 0x01); i++)
127 			snd_gf1_uart_get(gus);	/* clean Rx */
128 		if (i >= 1000)
129 			snd_printk(KERN_ERR "gus midi uart init read - cleanup error\n");
130 	}
131 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
132 #if 0
133 	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));
134 	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));
135 #endif
136 	return 0;
137 }
138 
139 static int snd_gf1_uart_output_close(struct snd_rawmidi_substream *substream)
140 {
141 	unsigned long flags;
142 	struct snd_gus_card *gus;
143 
144 	gus = substream->rmidi->private_data;
145 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
146 	if (gus->gf1.interrupt_handler_midi_in != snd_gf1_interrupt_midi_in)
147 		snd_gf1_uart_reset(gus, 1);
148 	snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_MIDI_OUT);
149 	gus->midi_substream_output = NULL;
150 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
151 	return 0;
152 }
153 
154 static int snd_gf1_uart_input_close(struct snd_rawmidi_substream *substream)
155 {
156 	unsigned long flags;
157 	struct snd_gus_card *gus;
158 
159 	gus = substream->rmidi->private_data;
160 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
161 	if (gus->gf1.interrupt_handler_midi_out != snd_gf1_interrupt_midi_out)
162 		snd_gf1_uart_reset(gus, 1);
163 	snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_MIDI_IN);
164 	gus->midi_substream_input = NULL;
165 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
166 	return 0;
167 }
168 
169 static void snd_gf1_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
170 {
171 	struct snd_gus_card *gus;
172 	unsigned long flags;
173 
174 	gus = substream->rmidi->private_data;
175 
176 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
177 	if (up) {
178 		if ((gus->gf1.uart_cmd & 0x80) == 0)
179 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd | 0x80); /* enable Rx interrupts */
180 	} else {
181 		if (gus->gf1.uart_cmd & 0x80)
182 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x80); /* disable Rx interrupts */
183 	}
184 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
185 }
186 
187 static void snd_gf1_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
188 {
189 	unsigned long flags;
190 	struct snd_gus_card *gus;
191 	char byte;
192 	int timeout;
193 
194 	gus = substream->rmidi->private_data;
195 
196 	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
197 	if (up) {
198 		if ((gus->gf1.uart_cmd & 0x20) == 0) {
199 			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
200 			/* wait for empty Rx - Tx is probably unlocked */
201 			timeout = 10000;
202 			while (timeout-- > 0 && snd_gf1_uart_stat(gus) & 0x01);
203 			/* Tx FIFO free? */
204 			spin_lock_irqsave(&gus->uart_cmd_lock, flags);
205 			if (gus->gf1.uart_cmd & 0x20) {
206 				spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
207 				return;
208 			}
209 			if (snd_gf1_uart_stat(gus) & 0x02) {
210 				if (snd_rawmidi_transmit(substream, &byte, 1) != 1) {
211 					spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
212 					return;
213 				}
214 				snd_gf1_uart_put(gus, byte);
215 			}
216 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd | 0x20);	/* enable Tx interrupt */
217 		}
218 	} else {
219 		if (gus->gf1.uart_cmd & 0x20)
220 			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x20);
221 	}
222 	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
223 }
224 
225 static struct snd_rawmidi_ops snd_gf1_uart_output =
226 {
227 	.open =		snd_gf1_uart_output_open,
228 	.close =	snd_gf1_uart_output_close,
229 	.trigger =	snd_gf1_uart_output_trigger,
230 };
231 
232 static struct snd_rawmidi_ops snd_gf1_uart_input =
233 {
234 	.open =		snd_gf1_uart_input_open,
235 	.close =	snd_gf1_uart_input_close,
236 	.trigger =	snd_gf1_uart_input_trigger,
237 };
238 
239 int snd_gf1_rawmidi_new(struct snd_gus_card * gus, int device, struct snd_rawmidi ** rrawmidi)
240 {
241 	struct snd_rawmidi *rmidi;
242 	int err;
243 
244 	if (rrawmidi)
245 		*rrawmidi = NULL;
246 	if ((err = snd_rawmidi_new(gus->card, "GF1", device, 1, 1, &rmidi)) < 0)
247 		return err;
248 	strcpy(rmidi->name, gus->interwave ? "AMD InterWave" : "GF1");
249 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_gf1_uart_output);
250 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_gf1_uart_input);
251 	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT | SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX;
252 	rmidi->private_data = gus;
253 	gus->midi_uart = rmidi;
254 	if (rrawmidi)
255 		*rrawmidi = rmidi;
256 	return err;
257 }
258