xref: /openbmc/linux/sound/pci/emu10k1/emumpu401.c (revision ded1ffea)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *  Routines for control of EMU10K1 MPU-401 in UART mode
5  */
6 
7 #include <linux/time.h>
8 #include <linux/init.h>
9 #include <sound/core.h>
10 #include <sound/emu10k1.h>
11 
12 #define EMU10K1_MIDI_MODE_INPUT		(1<<0)
13 #define EMU10K1_MIDI_MODE_OUTPUT	(1<<1)
14 
15 static inline unsigned char mpu401_read(struct snd_emu10k1 *emu,
16 					struct snd_emu10k1_midi *mpu, int idx)
17 {
18 	if (emu->audigy)
19 		return (unsigned char)snd_emu10k1_ptr_read(emu, mpu->port + idx, 0);
20 	else
21 		return inb(emu->port + mpu->port + idx);
22 }
23 
24 static inline void mpu401_write(struct snd_emu10k1 *emu,
25 				struct snd_emu10k1_midi *mpu, int data, int idx)
26 {
27 	if (emu->audigy)
28 		snd_emu10k1_ptr_write(emu, mpu->port + idx, 0, data);
29 	else
30 		outb(data, emu->port + mpu->port + idx);
31 }
32 
33 #define mpu401_write_data(emu, mpu, data)	mpu401_write(emu, mpu, data, 0)
34 #define mpu401_write_cmd(emu, mpu, data)	mpu401_write(emu, mpu, data, 1)
35 #define mpu401_read_data(emu, mpu)		mpu401_read(emu, mpu, 0)
36 #define mpu401_read_stat(emu, mpu)		mpu401_read(emu, mpu, 1)
37 
38 #define mpu401_input_avail(emu,mpu)	(!(mpu401_read_stat(emu,mpu) & 0x80))
39 #define mpu401_output_ready(emu,mpu)	(!(mpu401_read_stat(emu,mpu) & 0x40))
40 
41 #define MPU401_RESET		0xff
42 #define MPU401_ENTER_UART	0x3f
43 #define MPU401_ACK		0xfe
44 
45 static void mpu401_clear_rx(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *mpu)
46 {
47 	int timeout = 100000;
48 	for (; timeout > 0 && mpu401_input_avail(emu, mpu); timeout--)
49 		mpu401_read_data(emu, mpu);
50 #ifdef CONFIG_SND_DEBUG
51 	if (timeout <= 0)
52 		dev_err(emu->card->dev,
53 			"cmd: clear rx timeout (status = 0x%x)\n",
54 			mpu401_read_stat(emu, mpu));
55 #endif
56 }
57 
58 /*
59 
60  */
61 
62 static void do_emu10k1_midi_interrupt(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *midi, unsigned int status)
63 {
64 	unsigned char byte;
65 
66 	if (midi->rmidi == NULL) {
67 		snd_emu10k1_intr_disable(emu, midi->tx_enable | midi->rx_enable);
68 		return;
69 	}
70 
71 	spin_lock(&midi->input_lock);
72 	if ((status & midi->ipr_rx) && mpu401_input_avail(emu, midi)) {
73 		if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
74 			mpu401_clear_rx(emu, midi);
75 		} else {
76 			byte = mpu401_read_data(emu, midi);
77 			if (midi->substream_input)
78 				snd_rawmidi_receive(midi->substream_input, &byte, 1);
79 		}
80 	}
81 	spin_unlock(&midi->input_lock);
82 
83 	spin_lock(&midi->output_lock);
84 	if ((status & midi->ipr_tx) && mpu401_output_ready(emu, midi)) {
85 		if (midi->substream_output &&
86 		    snd_rawmidi_transmit(midi->substream_output, &byte, 1) == 1) {
87 			mpu401_write_data(emu, midi, byte);
88 		} else {
89 			snd_emu10k1_intr_disable(emu, midi->tx_enable);
90 		}
91 	}
92 	spin_unlock(&midi->output_lock);
93 }
94 
95 static void snd_emu10k1_midi_interrupt(struct snd_emu10k1 *emu, unsigned int status)
96 {
97 	do_emu10k1_midi_interrupt(emu, &emu->midi, status);
98 }
99 
100 static void snd_emu10k1_midi_interrupt2(struct snd_emu10k1 *emu, unsigned int status)
101 {
102 	do_emu10k1_midi_interrupt(emu, &emu->midi2, status);
103 }
104 
105 static int snd_emu10k1_midi_cmd(struct snd_emu10k1 * emu, struct snd_emu10k1_midi *midi, unsigned char cmd, int ack)
106 {
107 	int timeout, ok;
108 
109 	spin_lock_irq(&midi->input_lock);
110 	mpu401_write_data(emu, midi, 0x00);
111 	/* mpu401_clear_rx(emu, midi); */
112 
113 	mpu401_write_cmd(emu, midi, cmd);
114 	if (ack) {
115 		ok = 0;
116 		timeout = 10000;
117 		while (!ok && timeout-- > 0) {
118 			if (mpu401_input_avail(emu, midi)) {
119 				if (mpu401_read_data(emu, midi) == MPU401_ACK)
120 					ok = 1;
121 			}
122 		}
123 		if (!ok && mpu401_read_data(emu, midi) == MPU401_ACK)
124 			ok = 1;
125 	} else {
126 		ok = 1;
127 	}
128 	spin_unlock_irq(&midi->input_lock);
129 	if (!ok) {
130 		dev_err(emu->card->dev,
131 			"midi_cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)!!!\n",
132 			   cmd, emu->port,
133 			   mpu401_read_stat(emu, midi),
134 			   mpu401_read_data(emu, midi));
135 		return 1;
136 	}
137 	return 0;
138 }
139 
140 static int snd_emu10k1_midi_input_open(struct snd_rawmidi_substream *substream)
141 {
142 	struct snd_emu10k1 *emu;
143 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
144 
145 	emu = midi->emu;
146 	if (snd_BUG_ON(!emu))
147 		return -ENXIO;
148 	spin_lock_irq(&midi->open_lock);
149 	midi->midi_mode |= EMU10K1_MIDI_MODE_INPUT;
150 	midi->substream_input = substream;
151 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
152 		spin_unlock_irq(&midi->open_lock);
153 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
154 			goto error_out;
155 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
156 			goto error_out;
157 	} else {
158 		spin_unlock_irq(&midi->open_lock);
159 	}
160 	return 0;
161 
162 error_out:
163 	return -EIO;
164 }
165 
166 static int snd_emu10k1_midi_output_open(struct snd_rawmidi_substream *substream)
167 {
168 	struct snd_emu10k1 *emu;
169 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
170 
171 	emu = midi->emu;
172 	if (snd_BUG_ON(!emu))
173 		return -ENXIO;
174 	spin_lock_irq(&midi->open_lock);
175 	midi->midi_mode |= EMU10K1_MIDI_MODE_OUTPUT;
176 	midi->substream_output = substream;
177 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
178 		spin_unlock_irq(&midi->open_lock);
179 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
180 			goto error_out;
181 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
182 			goto error_out;
183 	} else {
184 		spin_unlock_irq(&midi->open_lock);
185 	}
186 	return 0;
187 
188 error_out:
189 	return -EIO;
190 }
191 
192 static int snd_emu10k1_midi_input_close(struct snd_rawmidi_substream *substream)
193 {
194 	struct snd_emu10k1 *emu;
195 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
196 	int err = 0;
197 
198 	emu = midi->emu;
199 	if (snd_BUG_ON(!emu))
200 		return -ENXIO;
201 	spin_lock_irq(&midi->open_lock);
202 	snd_emu10k1_intr_disable(emu, midi->rx_enable);
203 	midi->midi_mode &= ~EMU10K1_MIDI_MODE_INPUT;
204 	midi->substream_input = NULL;
205 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
206 		spin_unlock_irq(&midi->open_lock);
207 		err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
208 	} else {
209 		spin_unlock_irq(&midi->open_lock);
210 	}
211 	return err;
212 }
213 
214 static int snd_emu10k1_midi_output_close(struct snd_rawmidi_substream *substream)
215 {
216 	struct snd_emu10k1 *emu;
217 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
218 	int err = 0;
219 
220 	emu = midi->emu;
221 	if (snd_BUG_ON(!emu))
222 		return -ENXIO;
223 	spin_lock_irq(&midi->open_lock);
224 	snd_emu10k1_intr_disable(emu, midi->tx_enable);
225 	midi->midi_mode &= ~EMU10K1_MIDI_MODE_OUTPUT;
226 	midi->substream_output = NULL;
227 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
228 		spin_unlock_irq(&midi->open_lock);
229 		err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
230 	} else {
231 		spin_unlock_irq(&midi->open_lock);
232 	}
233 	return err;
234 }
235 
236 static void snd_emu10k1_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
237 {
238 	struct snd_emu10k1 *emu;
239 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
240 	emu = midi->emu;
241 	if (snd_BUG_ON(!emu))
242 		return;
243 
244 	if (up)
245 		snd_emu10k1_intr_enable(emu, midi->rx_enable);
246 	else
247 		snd_emu10k1_intr_disable(emu, midi->rx_enable);
248 }
249 
250 static void snd_emu10k1_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
251 {
252 	struct snd_emu10k1 *emu;
253 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
254 
255 	emu = midi->emu;
256 	if (snd_BUG_ON(!emu))
257 		return;
258 
259 	if (up) {
260 		int max = 4;
261 		unsigned char byte;
262 
263 		/* try to send some amount of bytes here before interrupts */
264 		spin_lock_irq(&midi->output_lock);
265 		while (max > 0) {
266 			if (mpu401_output_ready(emu, midi)) {
267 				if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT) ||
268 				    snd_rawmidi_transmit(substream, &byte, 1) != 1) {
269 					/* no more data */
270 					spin_unlock_irq(&midi->output_lock);
271 					return;
272 				}
273 				mpu401_write_data(emu, midi, byte);
274 				max--;
275 			} else {
276 				break;
277 			}
278 		}
279 		spin_unlock_irq(&midi->output_lock);
280 		snd_emu10k1_intr_enable(emu, midi->tx_enable);
281 	} else {
282 		snd_emu10k1_intr_disable(emu, midi->tx_enable);
283 	}
284 }
285 
286 /*
287 
288  */
289 
290 static const struct snd_rawmidi_ops snd_emu10k1_midi_output =
291 {
292 	.open =		snd_emu10k1_midi_output_open,
293 	.close =	snd_emu10k1_midi_output_close,
294 	.trigger =	snd_emu10k1_midi_output_trigger,
295 };
296 
297 static const struct snd_rawmidi_ops snd_emu10k1_midi_input =
298 {
299 	.open =		snd_emu10k1_midi_input_open,
300 	.close =	snd_emu10k1_midi_input_close,
301 	.trigger =	snd_emu10k1_midi_input_trigger,
302 };
303 
304 static void snd_emu10k1_midi_free(struct snd_rawmidi *rmidi)
305 {
306 	struct snd_emu10k1_midi *midi = rmidi->private_data;
307 	midi->interrupt = NULL;
308 	midi->rmidi = NULL;
309 }
310 
311 static int emu10k1_midi_init(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *midi, int device, char *name)
312 {
313 	struct snd_rawmidi *rmidi;
314 	int err;
315 
316 	err = snd_rawmidi_new(emu->card, name, device, 1, 1, &rmidi);
317 	if (err < 0)
318 		return err;
319 	midi->emu = emu;
320 	spin_lock_init(&midi->open_lock);
321 	spin_lock_init(&midi->input_lock);
322 	spin_lock_init(&midi->output_lock);
323 	strcpy(rmidi->name, name);
324 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_emu10k1_midi_output);
325 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_emu10k1_midi_input);
326 	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
327 	                     SNDRV_RAWMIDI_INFO_INPUT |
328 	                     SNDRV_RAWMIDI_INFO_DUPLEX;
329 	rmidi->private_data = midi;
330 	rmidi->private_free = snd_emu10k1_midi_free;
331 	midi->rmidi = rmidi;
332 	return 0;
333 }
334 
335 int snd_emu10k1_midi(struct snd_emu10k1 *emu)
336 {
337 	struct snd_emu10k1_midi *midi = &emu->midi;
338 	int err;
339 
340 	err = emu10k1_midi_init(emu, midi, 0, "EMU10K1 MPU-401 (UART)");
341 	if (err < 0)
342 		return err;
343 
344 	midi->tx_enable = INTE_MIDITXENABLE;
345 	midi->rx_enable = INTE_MIDIRXENABLE;
346 	midi->port = MUDATA;
347 	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
348 	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
349 	midi->interrupt = snd_emu10k1_midi_interrupt;
350 	return 0;
351 }
352 
353 int snd_emu10k1_audigy_midi(struct snd_emu10k1 *emu)
354 {
355 	struct snd_emu10k1_midi *midi;
356 	int err;
357 
358 	midi = &emu->midi;
359 	err = emu10k1_midi_init(emu, midi, 0, "Audigy MPU-401 (UART)");
360 	if (err < 0)
361 		return err;
362 
363 	midi->tx_enable = INTE_MIDITXENABLE;
364 	midi->rx_enable = INTE_MIDIRXENABLE;
365 	midi->port = A_MUDATA1;
366 	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
367 	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
368 	midi->interrupt = snd_emu10k1_midi_interrupt;
369 
370 	midi = &emu->midi2;
371 	err = emu10k1_midi_init(emu, midi, 1, "Audigy MPU-401 #2");
372 	if (err < 0)
373 		return err;
374 
375 	midi->tx_enable = INTE_A_MIDITXENABLE2;
376 	midi->rx_enable = INTE_A_MIDIRXENABLE2;
377 	midi->port = A_MUDATA2;
378 	midi->ipr_tx = IPR_A_MIDITRANSBUFEMPTY2;
379 	midi->ipr_rx = IPR_A_MIDIRECVBUFEMPTY2;
380 	midi->interrupt = snd_emu10k1_midi_interrupt2;
381 	return 0;
382 }
383