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 
mpu401_read(struct snd_emu10k1 * emu,struct snd_emu10k1_midi * mpu,int idx)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 
mpu401_write(struct snd_emu10k1 * emu,struct snd_emu10k1_midi * mpu,int data,int idx)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 
mpu401_clear_rx(struct snd_emu10k1 * emu,struct snd_emu10k1_midi * mpu)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 
do_emu10k1_midi_interrupt(struct snd_emu10k1 * emu,struct snd_emu10k1_midi * midi,unsigned int status)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 
snd_emu10k1_midi_interrupt(struct snd_emu10k1 * emu,unsigned int status)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 
snd_emu10k1_midi_interrupt2(struct snd_emu10k1 * emu,unsigned int status)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 
snd_emu10k1_midi_cmd(struct snd_emu10k1 * emu,struct snd_emu10k1_midi * midi,unsigned char cmd,int ack)105 static int snd_emu10k1_midi_cmd(struct snd_emu10k1 * emu, struct snd_emu10k1_midi *midi, unsigned char cmd, int ack)
106 {
107 	unsigned long flags;
108 	int timeout, ok;
109 
110 	spin_lock_irqsave(&midi->input_lock, flags);
111 	mpu401_write_data(emu, midi, 0x00);
112 	/* mpu401_clear_rx(emu, midi); */
113 
114 	mpu401_write_cmd(emu, midi, cmd);
115 	if (ack) {
116 		ok = 0;
117 		timeout = 10000;
118 		while (!ok && timeout-- > 0) {
119 			if (mpu401_input_avail(emu, midi)) {
120 				if (mpu401_read_data(emu, midi) == MPU401_ACK)
121 					ok = 1;
122 			}
123 		}
124 		if (!ok && mpu401_read_data(emu, midi) == MPU401_ACK)
125 			ok = 1;
126 	} else {
127 		ok = 1;
128 	}
129 	spin_unlock_irqrestore(&midi->input_lock, flags);
130 	if (!ok) {
131 		dev_err(emu->card->dev,
132 			"midi_cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)!!!\n",
133 			   cmd, emu->port,
134 			   mpu401_read_stat(emu, midi),
135 			   mpu401_read_data(emu, midi));
136 		return 1;
137 	}
138 	return 0;
139 }
140 
snd_emu10k1_midi_input_open(struct snd_rawmidi_substream * substream)141 static int snd_emu10k1_midi_input_open(struct snd_rawmidi_substream *substream)
142 {
143 	struct snd_emu10k1 *emu;
144 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
145 	unsigned long flags;
146 
147 	emu = midi->emu;
148 	if (snd_BUG_ON(!emu))
149 		return -ENXIO;
150 	spin_lock_irqsave(&midi->open_lock, flags);
151 	midi->midi_mode |= EMU10K1_MIDI_MODE_INPUT;
152 	midi->substream_input = substream;
153 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
154 		spin_unlock_irqrestore(&midi->open_lock, flags);
155 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
156 			goto error_out;
157 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
158 			goto error_out;
159 	} else {
160 		spin_unlock_irqrestore(&midi->open_lock, flags);
161 	}
162 	return 0;
163 
164 error_out:
165 	return -EIO;
166 }
167 
snd_emu10k1_midi_output_open(struct snd_rawmidi_substream * substream)168 static int snd_emu10k1_midi_output_open(struct snd_rawmidi_substream *substream)
169 {
170 	struct snd_emu10k1 *emu;
171 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
172 	unsigned long flags;
173 
174 	emu = midi->emu;
175 	if (snd_BUG_ON(!emu))
176 		return -ENXIO;
177 	spin_lock_irqsave(&midi->open_lock, flags);
178 	midi->midi_mode |= EMU10K1_MIDI_MODE_OUTPUT;
179 	midi->substream_output = substream;
180 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
181 		spin_unlock_irqrestore(&midi->open_lock, flags);
182 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
183 			goto error_out;
184 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
185 			goto error_out;
186 	} else {
187 		spin_unlock_irqrestore(&midi->open_lock, flags);
188 	}
189 	return 0;
190 
191 error_out:
192 	return -EIO;
193 }
194 
snd_emu10k1_midi_input_close(struct snd_rawmidi_substream * substream)195 static int snd_emu10k1_midi_input_close(struct snd_rawmidi_substream *substream)
196 {
197 	struct snd_emu10k1 *emu;
198 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
199 	unsigned long flags;
200 	int err = 0;
201 
202 	emu = midi->emu;
203 	if (snd_BUG_ON(!emu))
204 		return -ENXIO;
205 	spin_lock_irqsave(&midi->open_lock, flags);
206 	snd_emu10k1_intr_disable(emu, midi->rx_enable);
207 	midi->midi_mode &= ~EMU10K1_MIDI_MODE_INPUT;
208 	midi->substream_input = NULL;
209 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
210 		spin_unlock_irqrestore(&midi->open_lock, flags);
211 		err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
212 	} else {
213 		spin_unlock_irqrestore(&midi->open_lock, flags);
214 	}
215 	return err;
216 }
217 
snd_emu10k1_midi_output_close(struct snd_rawmidi_substream * substream)218 static int snd_emu10k1_midi_output_close(struct snd_rawmidi_substream *substream)
219 {
220 	struct snd_emu10k1 *emu;
221 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
222 	unsigned long flags;
223 	int err = 0;
224 
225 	emu = midi->emu;
226 	if (snd_BUG_ON(!emu))
227 		return -ENXIO;
228 	spin_lock_irqsave(&midi->open_lock, flags);
229 	snd_emu10k1_intr_disable(emu, midi->tx_enable);
230 	midi->midi_mode &= ~EMU10K1_MIDI_MODE_OUTPUT;
231 	midi->substream_output = NULL;
232 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
233 		spin_unlock_irqrestore(&midi->open_lock, flags);
234 		err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
235 	} else {
236 		spin_unlock_irqrestore(&midi->open_lock, flags);
237 	}
238 	return err;
239 }
240 
snd_emu10k1_midi_input_trigger(struct snd_rawmidi_substream * substream,int up)241 static void snd_emu10k1_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
242 {
243 	struct snd_emu10k1 *emu;
244 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
245 	emu = midi->emu;
246 	if (snd_BUG_ON(!emu))
247 		return;
248 
249 	if (up)
250 		snd_emu10k1_intr_enable(emu, midi->rx_enable);
251 	else
252 		snd_emu10k1_intr_disable(emu, midi->rx_enable);
253 }
254 
snd_emu10k1_midi_output_trigger(struct snd_rawmidi_substream * substream,int up)255 static void snd_emu10k1_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
256 {
257 	struct snd_emu10k1 *emu;
258 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
259 	unsigned long flags;
260 
261 	emu = midi->emu;
262 	if (snd_BUG_ON(!emu))
263 		return;
264 
265 	if (up) {
266 		int max = 4;
267 		unsigned char byte;
268 
269 		/* try to send some amount of bytes here before interrupts */
270 		spin_lock_irqsave(&midi->output_lock, flags);
271 		while (max > 0) {
272 			if (mpu401_output_ready(emu, midi)) {
273 				if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT) ||
274 				    snd_rawmidi_transmit(substream, &byte, 1) != 1) {
275 					/* no more data */
276 					spin_unlock_irqrestore(&midi->output_lock, flags);
277 					return;
278 				}
279 				mpu401_write_data(emu, midi, byte);
280 				max--;
281 			} else {
282 				break;
283 			}
284 		}
285 		spin_unlock_irqrestore(&midi->output_lock, flags);
286 		snd_emu10k1_intr_enable(emu, midi->tx_enable);
287 	} else {
288 		snd_emu10k1_intr_disable(emu, midi->tx_enable);
289 	}
290 }
291 
292 /*
293 
294  */
295 
296 static const struct snd_rawmidi_ops snd_emu10k1_midi_output =
297 {
298 	.open =		snd_emu10k1_midi_output_open,
299 	.close =	snd_emu10k1_midi_output_close,
300 	.trigger =	snd_emu10k1_midi_output_trigger,
301 };
302 
303 static const struct snd_rawmidi_ops snd_emu10k1_midi_input =
304 {
305 	.open =		snd_emu10k1_midi_input_open,
306 	.close =	snd_emu10k1_midi_input_close,
307 	.trigger =	snd_emu10k1_midi_input_trigger,
308 };
309 
snd_emu10k1_midi_free(struct snd_rawmidi * rmidi)310 static void snd_emu10k1_midi_free(struct snd_rawmidi *rmidi)
311 {
312 	struct snd_emu10k1_midi *midi = rmidi->private_data;
313 	midi->interrupt = NULL;
314 	midi->rmidi = NULL;
315 }
316 
emu10k1_midi_init(struct snd_emu10k1 * emu,struct snd_emu10k1_midi * midi,int device,char * name)317 static int emu10k1_midi_init(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *midi, int device, char *name)
318 {
319 	struct snd_rawmidi *rmidi;
320 	int err;
321 
322 	err = snd_rawmidi_new(emu->card, name, device, 1, 1, &rmidi);
323 	if (err < 0)
324 		return err;
325 	midi->emu = emu;
326 	spin_lock_init(&midi->open_lock);
327 	spin_lock_init(&midi->input_lock);
328 	spin_lock_init(&midi->output_lock);
329 	strcpy(rmidi->name, name);
330 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_emu10k1_midi_output);
331 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_emu10k1_midi_input);
332 	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
333 	                     SNDRV_RAWMIDI_INFO_INPUT |
334 	                     SNDRV_RAWMIDI_INFO_DUPLEX;
335 	rmidi->private_data = midi;
336 	rmidi->private_free = snd_emu10k1_midi_free;
337 	midi->rmidi = rmidi;
338 	return 0;
339 }
340 
snd_emu10k1_midi(struct snd_emu10k1 * emu)341 int snd_emu10k1_midi(struct snd_emu10k1 *emu)
342 {
343 	struct snd_emu10k1_midi *midi = &emu->midi;
344 	int err;
345 
346 	err = emu10k1_midi_init(emu, midi, 0, "EMU10K1 MPU-401 (UART)");
347 	if (err < 0)
348 		return err;
349 
350 	midi->tx_enable = INTE_MIDITXENABLE;
351 	midi->rx_enable = INTE_MIDIRXENABLE;
352 	midi->port = MUDATA;
353 	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
354 	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
355 	midi->interrupt = snd_emu10k1_midi_interrupt;
356 	return 0;
357 }
358 
snd_emu10k1_audigy_midi(struct snd_emu10k1 * emu)359 int snd_emu10k1_audigy_midi(struct snd_emu10k1 *emu)
360 {
361 	struct snd_emu10k1_midi *midi;
362 	int err;
363 
364 	midi = &emu->midi;
365 	err = emu10k1_midi_init(emu, midi, 0, "Audigy MPU-401 (UART)");
366 	if (err < 0)
367 		return err;
368 
369 	midi->tx_enable = INTE_MIDITXENABLE;
370 	midi->rx_enable = INTE_MIDIRXENABLE;
371 	midi->port = A_MUDATA1;
372 	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
373 	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
374 	midi->interrupt = snd_emu10k1_midi_interrupt;
375 
376 	midi = &emu->midi2;
377 	err = emu10k1_midi_init(emu, midi, 1, "Audigy MPU-401 #2");
378 	if (err < 0)
379 		return err;
380 
381 	midi->tx_enable = INTE_A_MIDITXENABLE2;
382 	midi->rx_enable = INTE_A_MIDIRXENABLE2;
383 	midi->port = A_MUDATA2;
384 	midi->ipr_tx = IPR_A_MIDITRANSBUFEMPTY2;
385 	midi->ipr_rx = IPR_A_MIDIRECVBUFEMPTY2;
386 	midi->interrupt = snd_emu10k1_midi_interrupt2;
387 	return 0;
388 }
389