1 /*
2  * sound/oss/sb_midi.c
3  *
4  * The low level driver for the Sound Blaster DS chips.
5  *
6  *
7  * Copyright (C) by Hannu Savolainen 1993-1997
8  *
9  * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
10  * Version 2 (June 1991). See the "COPYING" file distributed with this software
11  * for more info.
12  */
13 
14 #include <linux/spinlock.h>
15 #include <linux/slab.h>
16 
17 #include "sound_config.h"
18 
19 #include "sb.h"
20 #undef SB_TEST_IRQ
21 
22 /*
23  * The DSP channel can be used either for input or output. Variable
24  * 'sb_irq_mode' will be set when the program calls read or write first time
25  * after open. Current version doesn't support mode changes without closing
26  * and reopening the device. Support for this feature may be implemented in a
27  * future version of this driver.
28  */
29 
30 
sb_midi_open(int dev,int mode,void (* input)(int dev,unsigned char data),void (* output)(int dev))31 static int sb_midi_open(int dev, int mode,
32 	     void            (*input) (int dev, unsigned char data),
33 	     void            (*output) (int dev)
34 )
35 {
36 	sb_devc *devc = midi_devs[dev]->devc;
37 	unsigned long flags;
38 
39 	if (devc == NULL)
40 		return -ENXIO;
41 
42 	spin_lock_irqsave(&devc->lock, flags);
43 	if (devc->opened)
44 	{
45 		spin_unlock_irqrestore(&devc->lock, flags);
46 		return -EBUSY;
47 	}
48 	devc->opened = 1;
49 	spin_unlock_irqrestore(&devc->lock, flags);
50 
51 	devc->irq_mode = IMODE_MIDI;
52 	devc->midi_broken = 0;
53 
54 	sb_dsp_reset(devc);
55 
56 	if (!sb_dsp_command(devc, 0x35))	/* Start MIDI UART mode */
57 	{
58 		  devc->opened = 0;
59 		  return -EIO;
60 	}
61 	devc->intr_active = 1;
62 
63 	if (mode & OPEN_READ)
64 	{
65 		devc->input_opened = 1;
66 		devc->midi_input_intr = input;
67 	}
68 	return 0;
69 }
70 
sb_midi_close(int dev)71 static void sb_midi_close(int dev)
72 {
73 	sb_devc *devc = midi_devs[dev]->devc;
74 	unsigned long flags;
75 
76 	if (devc == NULL)
77 		return;
78 
79 	spin_lock_irqsave(&devc->lock, flags);
80 	sb_dsp_reset(devc);
81 	devc->intr_active = 0;
82 	devc->input_opened = 0;
83 	devc->opened = 0;
84 	spin_unlock_irqrestore(&devc->lock, flags);
85 }
86 
sb_midi_out(int dev,unsigned char midi_byte)87 static int sb_midi_out(int dev, unsigned char midi_byte)
88 {
89 	sb_devc *devc = midi_devs[dev]->devc;
90 
91 	if (devc == NULL)
92 		return 1;
93 
94 	if (devc->midi_broken)
95 		return 1;
96 
97 	if (!sb_dsp_command(devc, midi_byte))
98 	{
99 		devc->midi_broken = 1;
100 		return 1;
101 	}
102 	return 1;
103 }
104 
sb_midi_start_read(int dev)105 static int sb_midi_start_read(int dev)
106 {
107 	return 0;
108 }
109 
sb_midi_end_read(int dev)110 static int sb_midi_end_read(int dev)
111 {
112 	sb_devc *devc = midi_devs[dev]->devc;
113 
114 	if (devc == NULL)
115 		return -ENXIO;
116 
117 	sb_dsp_reset(devc);
118 	devc->intr_active = 0;
119 	return 0;
120 }
121 
sb_midi_ioctl(int dev,unsigned cmd,void __user * arg)122 static int sb_midi_ioctl(int dev, unsigned cmd, void __user *arg)
123 {
124         return -EINVAL;
125 }
126 
sb_midi_interrupt(sb_devc * devc)127 void sb_midi_interrupt(sb_devc * devc)
128 {
129 	unsigned long   flags;
130 	unsigned char   data;
131 
132 	if (devc == NULL)
133 		return;
134 
135 	spin_lock_irqsave(&devc->lock, flags);
136 
137 	data = inb(DSP_READ);
138 	if (devc->input_opened)
139 		devc->midi_input_intr(devc->my_mididev, data);
140 
141 	spin_unlock_irqrestore(&devc->lock, flags);
142 }
143 
144 #define MIDI_SYNTH_NAME	"Sound Blaster Midi"
145 #define MIDI_SYNTH_CAPS	0
146 #include "midi_synth.h"
147 
148 static struct midi_operations sb_midi_operations =
149 {
150 	.owner		= THIS_MODULE,
151 	.info		= {"Sound Blaster", 0, 0, SNDCARD_SB},
152 	.converter	= &std_midi_synth,
153 	.in_info	= {0},
154 	.open		= sb_midi_open,
155 	.close		= sb_midi_close,
156 	.ioctl		= sb_midi_ioctl,
157 	.outputc	= sb_midi_out,
158 	.start_read	= sb_midi_start_read,
159 	.end_read	= sb_midi_end_read,
160 };
161 
sb_dsp_midi_init(sb_devc * devc,struct module * owner)162 void sb_dsp_midi_init(sb_devc * devc, struct module *owner)
163 {
164 	int dev;
165 
166 	if (devc->model < 2)	/* No MIDI support for SB 1.x */
167 		return;
168 
169 	dev = sound_alloc_mididev();
170 
171 	if (dev == -1)
172 	{
173 		printk(KERN_ERR "sb_midi: too many MIDI devices detected\n");
174 		return;
175 	}
176 	std_midi_synth.midi_dev = devc->my_mididev = dev;
177 	midi_devs[dev] = kmalloc(sizeof(struct midi_operations), GFP_KERNEL);
178 	if (midi_devs[dev] == NULL)
179 	{
180 		printk(KERN_WARNING "Sound Blaster:  failed to allocate MIDI memory.\n");
181 		sound_unload_mididev(dev);
182 		  return;
183 	}
184 	memcpy((char *) midi_devs[dev], (char *) &sb_midi_operations,
185 	       sizeof(struct midi_operations));
186 
187 	if (owner)
188 			midi_devs[dev]->owner = owner;
189 
190 	midi_devs[dev]->devc = devc;
191 
192 
193 	midi_devs[dev]->converter = kmalloc(sizeof(struct synth_operations), GFP_KERNEL);
194 	if (midi_devs[dev]->converter == NULL)
195 	{
196 		  printk(KERN_WARNING "Sound Blaster:  failed to allocate MIDI memory.\n");
197 		  kfree(midi_devs[dev]);
198 		  sound_unload_mididev(dev);
199 		  return;
200 	}
201 	memcpy((char *) midi_devs[dev]->converter, (char *) &std_midi_synth,
202 	       sizeof(struct synth_operations));
203 
204 	midi_devs[dev]->converter->id = "SBMIDI";
205 	sequencer_init();
206 }
207