1/*
2 *  Copyright (c) by Jaroslav Kysela <perex@perex.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 <linux/delay.h>
23#include <linux/interrupt.h>
24#include <linux/time.h>
25#include <sound/core.h>
26#include <sound/gus.h>
27
28static void snd_gf1_interrupt_midi_in(struct snd_gus_card * gus)
29{
30	int count;
31	unsigned char stat, data, byte;
32	unsigned long flags;
33
34	count = 10;
35	while (count) {
36		spin_lock_irqsave(&gus->uart_cmd_lock, flags);
37		stat = snd_gf1_uart_stat(gus);
38		if (!(stat & 0x01)) {	/* data in Rx FIFO? */
39			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
40			count--;
41			continue;
42		}
43		count = 100;	/* arm counter to new value */
44		data = snd_gf1_uart_get(gus);
45		if (!(gus->gf1.uart_cmd & 0x80)) {
46			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
47			continue;
48		}
49		if (stat & 0x10) {	/* framing error */
50			gus->gf1.uart_framing++;
51			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
52			continue;
53		}
54		byte = snd_gf1_uart_get(gus);
55		spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
56		snd_rawmidi_receive(gus->midi_substream_input, &byte, 1);
57		if (stat & 0x20) {
58			gus->gf1.uart_overrun++;
59		}
60	}
61}
62
63static void snd_gf1_interrupt_midi_out(struct snd_gus_card * gus)
64{
65	char byte;
66	unsigned long flags;
67
68	/* try unlock output */
69	if (snd_gf1_uart_stat(gus) & 0x01)
70		snd_gf1_interrupt_midi_in(gus);
71
72	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
73	if (snd_gf1_uart_stat(gus) & 0x02) {	/* Tx FIFO free? */
74		if (snd_rawmidi_transmit(gus->midi_substream_output, &byte, 1) != 1) {	/* no other bytes or error */
75			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x20); /* disable Tx interrupt */
76		} else {
77			snd_gf1_uart_put(gus, byte);
78		}
79	}
80	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
81}
82
83static void snd_gf1_uart_reset(struct snd_gus_card * gus, int close)
84{
85	snd_gf1_uart_cmd(gus, 0x03);	/* reset */
86	if (!close && gus->uart_enable) {
87		udelay(160);
88		snd_gf1_uart_cmd(gus, 0x00);	/* normal operations */
89	}
90}
91
92static int snd_gf1_uart_output_open(struct snd_rawmidi_substream *substream)
93{
94	unsigned long flags;
95	struct snd_gus_card *gus;
96
97	gus = substream->rmidi->private_data;
98	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
99	if (!(gus->gf1.uart_cmd & 0x80)) {	/* input active? */
100		snd_gf1_uart_reset(gus, 0);
101	}
102	gus->gf1.interrupt_handler_midi_out = snd_gf1_interrupt_midi_out;
103	gus->midi_substream_output = substream;
104	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
105#if 0
106	snd_printk(KERN_DEBUG "write init - cmd = 0x%x, stat = 0x%x\n", gus->gf1.uart_cmd, snd_gf1_uart_stat(gus));
107#endif
108	return 0;
109}
110
111static int snd_gf1_uart_input_open(struct snd_rawmidi_substream *substream)
112{
113	unsigned long flags;
114	struct snd_gus_card *gus;
115	int i;
116
117	gus = substream->rmidi->private_data;
118	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
119	if (gus->gf1.interrupt_handler_midi_out != snd_gf1_interrupt_midi_out) {
120		snd_gf1_uart_reset(gus, 0);
121	}
122	gus->gf1.interrupt_handler_midi_in = snd_gf1_interrupt_midi_in;
123	gus->midi_substream_input = substream;
124	if (gus->uart_enable) {
125		for (i = 0; i < 1000 && (snd_gf1_uart_stat(gus) & 0x01); i++)
126			snd_gf1_uart_get(gus);	/* clean Rx */
127		if (i >= 1000)
128			snd_printk(KERN_ERR "gus midi uart init read - cleanup error\n");
129	}
130	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
131#if 0
132	snd_printk(KERN_DEBUG
133		   "read init - enable = %i, cmd = 0x%x, stat = 0x%x\n",
134		   gus->uart_enable, gus->gf1.uart_cmd, snd_gf1_uart_stat(gus));
135	snd_printk(KERN_DEBUG
136		   "[0x%x] reg (ctrl/status) = 0x%x, reg (data) = 0x%x "
137		   "(page = 0x%x)\n",
138		   gus->gf1.port + 0x100, inb(gus->gf1.port + 0x100),
139		   inb(gus->gf1.port + 0x101), inb(gus->gf1.port + 0x102));
140#endif
141	return 0;
142}
143
144static int snd_gf1_uart_output_close(struct snd_rawmidi_substream *substream)
145{
146	unsigned long flags;
147	struct snd_gus_card *gus;
148
149	gus = substream->rmidi->private_data;
150	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
151	if (gus->gf1.interrupt_handler_midi_in != snd_gf1_interrupt_midi_in)
152		snd_gf1_uart_reset(gus, 1);
153	snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_MIDI_OUT);
154	gus->midi_substream_output = NULL;
155	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
156	return 0;
157}
158
159static int snd_gf1_uart_input_close(struct snd_rawmidi_substream *substream)
160{
161	unsigned long flags;
162	struct snd_gus_card *gus;
163
164	gus = substream->rmidi->private_data;
165	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
166	if (gus->gf1.interrupt_handler_midi_out != snd_gf1_interrupt_midi_out)
167		snd_gf1_uart_reset(gus, 1);
168	snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_MIDI_IN);
169	gus->midi_substream_input = NULL;
170	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
171	return 0;
172}
173
174static void snd_gf1_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
175{
176	struct snd_gus_card *gus;
177	unsigned long flags;
178
179	gus = substream->rmidi->private_data;
180
181	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
182	if (up) {
183		if ((gus->gf1.uart_cmd & 0x80) == 0)
184			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd | 0x80); /* enable Rx interrupts */
185	} else {
186		if (gus->gf1.uart_cmd & 0x80)
187			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x80); /* disable Rx interrupts */
188	}
189	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
190}
191
192static void snd_gf1_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
193{
194	unsigned long flags;
195	struct snd_gus_card *gus;
196	char byte;
197	int timeout;
198
199	gus = substream->rmidi->private_data;
200
201	spin_lock_irqsave(&gus->uart_cmd_lock, flags);
202	if (up) {
203		if ((gus->gf1.uart_cmd & 0x20) == 0) {
204			spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
205			/* wait for empty Rx - Tx is probably unlocked */
206			timeout = 10000;
207			while (timeout-- > 0 && snd_gf1_uart_stat(gus) & 0x01);
208			/* Tx FIFO free? */
209			spin_lock_irqsave(&gus->uart_cmd_lock, flags);
210			if (gus->gf1.uart_cmd & 0x20) {
211				spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
212				return;
213			}
214			if (snd_gf1_uart_stat(gus) & 0x02) {
215				if (snd_rawmidi_transmit(substream, &byte, 1) != 1) {
216					spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
217					return;
218				}
219				snd_gf1_uart_put(gus, byte);
220			}
221			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd | 0x20);	/* enable Tx interrupt */
222		}
223	} else {
224		if (gus->gf1.uart_cmd & 0x20)
225			snd_gf1_uart_cmd(gus, gus->gf1.uart_cmd & ~0x20);
226	}
227	spin_unlock_irqrestore(&gus->uart_cmd_lock, flags);
228}
229
230static struct snd_rawmidi_ops snd_gf1_uart_output =
231{
232	.open =		snd_gf1_uart_output_open,
233	.close =	snd_gf1_uart_output_close,
234	.trigger =	snd_gf1_uart_output_trigger,
235};
236
237static struct snd_rawmidi_ops snd_gf1_uart_input =
238{
239	.open =		snd_gf1_uart_input_open,
240	.close =	snd_gf1_uart_input_close,
241	.trigger =	snd_gf1_uart_input_trigger,
242};
243
244int snd_gf1_rawmidi_new(struct snd_gus_card *gus, int device)
245{
246	struct snd_rawmidi *rmidi;
247	int err;
248
249	if ((err = snd_rawmidi_new(gus->card, "GF1", device, 1, 1, &rmidi)) < 0)
250		return err;
251	strcpy(rmidi->name, gus->interwave ? "AMD InterWave" : "GF1");
252	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_gf1_uart_output);
253	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_gf1_uart_input);
254	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT | SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX;
255	rmidi->private_data = gus;
256	gus->midi_uart = rmidi;
257	return err;
258}
259