1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 * Routines for the GF1 MIDI interface - like UART 6850
5 */
6
7 #include <linux/delay.h>
8 #include <linux/interrupt.h>
9 #include <linux/time.h>
10 #include <sound/core.h>
11 #include <sound/gus.h>
12
snd_gf1_interrupt_midi_in(struct snd_gus_card * gus)13 static void snd_gf1_interrupt_midi_in(struct snd_gus_card * gus)
14 {
15 int count;
16 unsigned char stat, byte;
17 __always_unused unsigned char data;
18 unsigned long flags;
19
20 count = 10;
21 while (count) {
22 spin_lock_irqsave(&gus->uart_cmd_lock, flags);
23 stat = snd_gf1_uart_stat(gus);
24 if (!(stat & 0x01)) { /* data in Rx FIFO? */
25 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
26 count--;
27 continue;
28 }
29 count = 100; /* arm counter to new value */
30 data = snd_gf1_uart_get(gus);
31 if (!(gus->gf1.uart_cmd & 0x80)) {
32 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
33 continue;
34 }
35 if (stat & 0x10) { /* framing error */
36 gus->gf1.uart_framing++;
37 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
38 continue;
39 }
40 byte = snd_gf1_uart_get(gus);
41 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
42 snd_rawmidi_receive(gus->midi_substream_input, &byte, 1);
43 if (stat & 0x20) {
44 gus->gf1.uart_overrun++;
45 }
46 }
47 }
48
snd_gf1_interrupt_midi_out(struct snd_gus_card * gus)49 static void snd_gf1_interrupt_midi_out(struct snd_gus_card * gus)
50 {
51 char byte;
52 unsigned long flags;
53
54 /* try unlock output */
55 if (snd_gf1_uart_stat(gus) & 0x01)
56 snd_gf1_interrupt_midi_in(gus);
57
58 spin_lock_irqsave(&gus->uart_cmd_lock, flags);
59 if (snd_gf1_uart_stat(gus) & 0x02) { /* Tx FIFO free? */
60 if (snd_rawmidi_transmit(gus->midi_substream_output, &byte, 1) != 1) { /* no other bytes or error */
61 snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x20); /* disable Tx interrupt */
62 } else {
63 snd_gf1_uart_put(gus, byte);
64 }
65 }
66 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
67 }
68
snd_gf1_uart_reset(struct snd_gus_card * gus,int close)69 static void snd_gf1_uart_reset(struct snd_gus_card * gus, int close)
70 {
71 snd_gf1_uart_cmd(gus, 0x03); /* reset */
72 if (!close && gus->uart_enable) {
73 udelay(160);
74 snd_gf1_uart_cmd(gus, 0x00); /* normal operations */
75 }
76 }
77
snd_gf1_uart_output_open(struct snd_rawmidi_substream * substream)78 static int snd_gf1_uart_output_open(struct snd_rawmidi_substream *substream)
79 {
80 unsigned long flags;
81 struct snd_gus_card *gus;
82
83 gus = substream->rmidi->private_data;
84 spin_lock_irqsave(&gus->uart_cmd_lock, flags);
85 if (!(gus->gf1.uart_cmd & 0x80)) { /* input active? */
86 snd_gf1_uart_reset(gus, 0);
87 }
88 gus->gf1.interrupt_handler_midi_out = snd_gf1_interrupt_midi_out;
89 gus->midi_substream_output = substream;
90 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
91 #if 0
92 dev_dbg(gus->card->dev,
93 "write init - cmd = 0x%x, stat = 0x%x\n",
94 gus->gf1.uart_cmd, snd_gf1_uart_stat(gus));
95 #endif
96 return 0;
97 }
98
snd_gf1_uart_input_open(struct snd_rawmidi_substream * substream)99 static int snd_gf1_uart_input_open(struct snd_rawmidi_substream *substream)
100 {
101 unsigned long flags;
102 struct snd_gus_card *gus;
103 int i;
104
105 gus = substream->rmidi->private_data;
106 spin_lock_irqsave(&gus->uart_cmd_lock, flags);
107 if (gus->gf1.interrupt_handler_midi_out != snd_gf1_interrupt_midi_out) {
108 snd_gf1_uart_reset(gus, 0);
109 }
110 gus->gf1.interrupt_handler_midi_in = snd_gf1_interrupt_midi_in;
111 gus->midi_substream_input = substream;
112 if (gus->uart_enable) {
113 for (i = 0; i < 1000 && (snd_gf1_uart_stat(gus) & 0x01); i++)
114 snd_gf1_uart_get(gus); /* clean Rx */
115 if (i >= 1000)
116 dev_err(gus->card->dev, "gus midi uart init read - cleanup error\n");
117 }
118 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
119 #if 0
120 dev_dbg(gus->card->dev,
121 "read init - enable = %i, cmd = 0x%x, stat = 0x%x\n",
122 gus->uart_enable, gus->gf1.uart_cmd, snd_gf1_uart_stat(gus));
123 dev_dbg(gus->card->dev,
124 "[0x%x] reg (ctrl/status) = 0x%x, reg (data) = 0x%x (page = 0x%x)\n",
125 gus->gf1.port + 0x100, inb(gus->gf1.port + 0x100),
126 inb(gus->gf1.port + 0x101), inb(gus->gf1.port + 0x102));
127 #endif
128 return 0;
129 }
130
snd_gf1_uart_output_close(struct snd_rawmidi_substream * substream)131 static int snd_gf1_uart_output_close(struct snd_rawmidi_substream *substream)
132 {
133 unsigned long flags;
134 struct snd_gus_card *gus;
135
136 gus = substream->rmidi->private_data;
137 spin_lock_irqsave(&gus->uart_cmd_lock, flags);
138 if (gus->gf1.interrupt_handler_midi_in != snd_gf1_interrupt_midi_in)
139 snd_gf1_uart_reset(gus, 1);
140 snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_MIDI_OUT);
141 gus->midi_substream_output = NULL;
142 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
143 return 0;
144 }
145
snd_gf1_uart_input_close(struct snd_rawmidi_substream * substream)146 static int snd_gf1_uart_input_close(struct snd_rawmidi_substream *substream)
147 {
148 unsigned long flags;
149 struct snd_gus_card *gus;
150
151 gus = substream->rmidi->private_data;
152 spin_lock_irqsave(&gus->uart_cmd_lock, flags);
153 if (gus->gf1.interrupt_handler_midi_out != snd_gf1_interrupt_midi_out)
154 snd_gf1_uart_reset(gus, 1);
155 snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_MIDI_IN);
156 gus->midi_substream_input = NULL;
157 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
158 return 0;
159 }
160
snd_gf1_uart_input_trigger(struct snd_rawmidi_substream * substream,int up)161 static void snd_gf1_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
162 {
163 struct snd_gus_card *gus;
164 unsigned long flags;
165
166 gus = substream->rmidi->private_data;
167
168 spin_lock_irqsave(&gus->uart_cmd_lock, flags);
169 if (up) {
170 if ((gus->gf1.uart_cmd & 0x80) == 0)
171 snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd | 0x80); /* enable Rx interrupts */
172 } else {
173 if (gus->gf1.uart_cmd & 0x80)
174 snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x80); /* disable Rx interrupts */
175 }
176 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
177 }
178
snd_gf1_uart_output_trigger(struct snd_rawmidi_substream * substream,int up)179 static void snd_gf1_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
180 {
181 unsigned long flags;
182 struct snd_gus_card *gus;
183 char byte;
184 int timeout;
185
186 gus = substream->rmidi->private_data;
187
188 spin_lock_irqsave(&gus->uart_cmd_lock, flags);
189 if (up) {
190 if ((gus->gf1.uart_cmd & 0x20) == 0) {
191 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
192 /* wait for empty Rx - Tx is probably unlocked */
193 timeout = 10000;
194 while (timeout-- > 0 && snd_gf1_uart_stat(gus) & 0x01);
195 /* Tx FIFO free? */
196 spin_lock_irqsave(&gus->uart_cmd_lock, flags);
197 if (gus->gf1.uart_cmd & 0x20) {
198 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
199 return;
200 }
201 if (snd_gf1_uart_stat(gus) & 0x02) {
202 if (snd_rawmidi_transmit(substream, &byte, 1) != 1) {
203 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
204 return;
205 }
206 snd_gf1_uart_put(gus, byte);
207 }
208 snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd | 0x20); /* enable Tx interrupt */
209 }
210 } else {
211 if (gus->gf1.uart_cmd & 0x20)
212 snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x20);
213 }
214 spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
215 }
216
217 static const struct snd_rawmidi_ops snd_gf1_uart_output =
218 {
219 .open = snd_gf1_uart_output_open,
220 .close = snd_gf1_uart_output_close,
221 .trigger = snd_gf1_uart_output_trigger,
222 };
223
224 static const struct snd_rawmidi_ops snd_gf1_uart_input =
225 {
226 .open = snd_gf1_uart_input_open,
227 .close = snd_gf1_uart_input_close,
228 .trigger = snd_gf1_uart_input_trigger,
229 };
230
snd_gf1_rawmidi_new(struct snd_gus_card * gus,int device)231 int snd_gf1_rawmidi_new(struct snd_gus_card *gus, int device)
232 {
233 struct snd_rawmidi *rmidi;
234 int err;
235
236 err = snd_rawmidi_new(gus->card, "GF1", device, 1, 1, &rmidi);
237 if (err < 0)
238 return err;
239 strcpy(rmidi->name, gus->interwave ? "AMD InterWave" : "GF1");
240 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_gf1_uart_output);
241 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_gf1_uart_input);
242 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT | SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX;
243 rmidi->private_data = gus;
244 gus->midi_uart = rmidi;
245 return err;
246 }
247