emumpu401.c

  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
 15static 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
 24static 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
 45static 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
 62static 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	scoped_guard(spinlock, &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	}
 82
 83	scoped_guard(spinlock, &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	}
 93}
 94
 95static void snd_emu10k1_midi_interrupt(struct snd_emu10k1 *emu, unsigned int status)
 96{
 97	do_emu10k1_midi_interrupt(emu, &emu->midi, status);
 98}
 99
100static void snd_emu10k1_midi_interrupt2(struct snd_emu10k1 *emu, unsigned int status)
101{
102	do_emu10k1_midi_interrupt(emu, &emu->midi2, status);
103}
104
105static 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	scoped_guard(spinlock_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	}
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
140static 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	scoped_guard(spinlock_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			return 0;
153	}
154	if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
155		return -EIO;
156	if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
157		return -EIO;
158	return 0;
159}
160
161static int snd_emu10k1_midi_output_open(struct snd_rawmidi_substream *substream)
162{
163	struct snd_emu10k1 *emu;
164	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
165
166	emu = midi->emu;
167	if (snd_BUG_ON(!emu))
168		return -ENXIO;
169	scoped_guard(spinlock_irq, &midi->open_lock) {
170		midi->midi_mode |= EMU10K1_MIDI_MODE_OUTPUT;
171		midi->substream_output = substream;
172		if (midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)
173			return 0;
174	}
175	if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
176		return -EIO;
177	if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
178		return -EIO;
179	return 0;
180}
181
182static int snd_emu10k1_midi_input_close(struct snd_rawmidi_substream *substream)
183{
184	struct snd_emu10k1 *emu;
185	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
186
187	emu = midi->emu;
188	if (snd_BUG_ON(!emu))
189		return -ENXIO;
190	scoped_guard(spinlock_irq, &midi->open_lock) {
191		snd_emu10k1_intr_disable(emu, midi->rx_enable);
192		midi->midi_mode &= ~EMU10K1_MIDI_MODE_INPUT;
193		midi->substream_input = NULL;
194		if (midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)
195			return 0;
196	}
197	return snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
198}
199
200static int snd_emu10k1_midi_output_close(struct snd_rawmidi_substream *substream)
201{
202	struct snd_emu10k1 *emu;
203	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
204
205	emu = midi->emu;
206	if (snd_BUG_ON(!emu))
207		return -ENXIO;
208	scoped_guard(spinlock_irq, &midi->open_lock) {
209		snd_emu10k1_intr_disable(emu, midi->tx_enable);
210		midi->midi_mode &= ~EMU10K1_MIDI_MODE_OUTPUT;
211		midi->substream_output = NULL;
212		if (midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)
213			return 0;
214	}
215	return snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
216}
217
218static void snd_emu10k1_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
219{
220	struct snd_emu10k1 *emu;
221	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
222	emu = midi->emu;
223	if (snd_BUG_ON(!emu))
224		return;
225
226	if (up)
227		snd_emu10k1_intr_enable(emu, midi->rx_enable);
228	else
229		snd_emu10k1_intr_disable(emu, midi->rx_enable);
230}
231
232static void snd_emu10k1_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
233{
234	struct snd_emu10k1 *emu;
235	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
236
237	emu = midi->emu;
238	if (snd_BUG_ON(!emu))
239		return;
240
241	if (up) {
242		int max = 4;
243		unsigned char byte;
244	
245		/* try to send some amount of bytes here before interrupts */
246		scoped_guard(spinlock_irq, &midi->output_lock) {
247			while (max > 0) {
248				if (mpu401_output_ready(emu, midi)) {
249					if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT) ||
250					    snd_rawmidi_transmit(substream, &byte, 1) != 1) {
251						/* no more data */
252						return;
253					}
254					mpu401_write_data(emu, midi, byte);
255					max--;
256				} else {
257					break;
258				}
259			}
260		}
261		snd_emu10k1_intr_enable(emu, midi->tx_enable);
262	} else {
263		snd_emu10k1_intr_disable(emu, midi->tx_enable);
264	}
265}
266
267/*
268
269 */
270
271static const struct snd_rawmidi_ops snd_emu10k1_midi_output =
272{
273	.open =		snd_emu10k1_midi_output_open,
274	.close =	snd_emu10k1_midi_output_close,
275	.trigger =	snd_emu10k1_midi_output_trigger,
276};
277
278static const struct snd_rawmidi_ops snd_emu10k1_midi_input =
279{
280	.open =		snd_emu10k1_midi_input_open,
281	.close =	snd_emu10k1_midi_input_close,
282	.trigger =	snd_emu10k1_midi_input_trigger,
283};
284
285static void snd_emu10k1_midi_free(struct snd_rawmidi *rmidi)
286{
287	struct snd_emu10k1_midi *midi = rmidi->private_data;
288	midi->interrupt = NULL;
289	midi->rmidi = NULL;
290}
291
292static int emu10k1_midi_init(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *midi, int device, char *name)
293{
294	struct snd_rawmidi *rmidi;
295	int err;
296
297	err = snd_rawmidi_new(emu->card, name, device, 1, 1, &rmidi);
298	if (err < 0)
299		return err;
300	midi->emu = emu;
301	spin_lock_init(&midi->open_lock);
302	spin_lock_init(&midi->input_lock);
303	spin_lock_init(&midi->output_lock);
304	strscpy(rmidi->name, name);
305	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_emu10k1_midi_output);
306	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_emu10k1_midi_input);
307	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
308	                     SNDRV_RAWMIDI_INFO_INPUT |
309	                     SNDRV_RAWMIDI_INFO_DUPLEX;
310	rmidi->private_data = midi;
311	rmidi->private_free = snd_emu10k1_midi_free;
312	midi->rmidi = rmidi;
313	return 0;
314}
315
316int snd_emu10k1_midi(struct snd_emu10k1 *emu)
317{
318	struct snd_emu10k1_midi *midi = &emu->midi;
319	int err;
320
321	err = emu10k1_midi_init(emu, midi, 0, "EMU10K1 MPU-401 (UART)");
322	if (err < 0)
323		return err;
324
325	midi->tx_enable = INTE_MIDITXENABLE;
326	midi->rx_enable = INTE_MIDIRXENABLE;
327	midi->port = MUDATA;
328	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
329	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
330	midi->interrupt = snd_emu10k1_midi_interrupt;
331	return 0;
332}
333
334int snd_emu10k1_audigy_midi(struct snd_emu10k1 *emu)
335{
336	struct snd_emu10k1_midi *midi;
337	int err;
338
339	midi = &emu->midi;
340	err = emu10k1_midi_init(emu, midi, 0, "Audigy 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 = A_MUDATA1;
347	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
348	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
349	midi->interrupt = snd_emu10k1_midi_interrupt;
350
351	midi = &emu->midi2;
352	err = emu10k1_midi_init(emu, midi, 1, "Audigy MPU-401 #2");
353	if (err < 0)
354		return err;
355
356	midi->tx_enable = INTE_A_MIDITXENABLE2;
357	midi->rx_enable = INTE_A_MIDIRXENABLE2;
358	midi->port = A_MUDATA2;
359	midi->ipr_tx = IPR_A_MIDITRANSBUFEMPTY2;
360	midi->ipr_rx = IPR_A_MIDIRECVBUFEMPTY2;
361	midi->interrupt = snd_emu10k1_midi_interrupt2;
362	return 0;
363}