1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (c) by Jaroslav Kysela <perex@perex.cz> |
4 | * Copyright (c) 2009 by Krzysztof Helt |
5 | * Routines for control of MPU-401 in UART mode |
6 | * |
7 | * MPU-401 supports UART mode which is not capable generate transmit |
8 | * interrupts thus output is done via polling. Also, if irq < 0, then |
9 | * input is done also via polling. Do not expect good performance. |
10 | */ |
11 | |
12 | #include <linux/io.h> |
13 | #include <linux/slab.h> |
14 | #include <linux/delay.h> |
15 | #include <linux/ioport.h> |
16 | #include <linux/errno.h> |
17 | #include <linux/export.h> |
18 | #include <sound/core.h> |
19 | #include <sound/rawmidi.h> |
20 | |
21 | #include "msnd.h" |
22 | |
23 | #define MSNDMIDI_MODE_BIT_INPUT 0 |
24 | #define MSNDMIDI_MODE_BIT_OUTPUT 1 |
25 | #define MSNDMIDI_MODE_BIT_INPUT_TRIGGER 2 |
26 | #define MSNDMIDI_MODE_BIT_OUTPUT_TRIGGER 3 |
27 | |
28 | struct snd_msndmidi { |
29 | struct snd_msnd *dev; |
30 | |
31 | unsigned long mode; /* MSNDMIDI_MODE_XXXX */ |
32 | |
33 | struct snd_rawmidi_substream *substream_input; |
34 | |
35 | spinlock_t input_lock; |
36 | }; |
37 | |
38 | /* |
39 | * input/output open/close - protected by open_mutex in rawmidi.c |
40 | */ |
41 | static int snd_msndmidi_input_open(struct snd_rawmidi_substream *substream) |
42 | { |
43 | struct snd_msndmidi *mpu; |
44 | |
45 | snd_printdd("snd_msndmidi_input_open()\n" ); |
46 | |
47 | mpu = substream->rmidi->private_data; |
48 | |
49 | mpu->substream_input = substream; |
50 | |
51 | snd_msnd_enable_irq(chip: mpu->dev); |
52 | |
53 | snd_msnd_send_dsp_cmd(chip: mpu->dev, HDEX_MIDI_IN_START); |
54 | set_bit(MSNDMIDI_MODE_BIT_INPUT, addr: &mpu->mode); |
55 | return 0; |
56 | } |
57 | |
58 | static int snd_msndmidi_input_close(struct snd_rawmidi_substream *substream) |
59 | { |
60 | struct snd_msndmidi *mpu; |
61 | |
62 | mpu = substream->rmidi->private_data; |
63 | snd_msnd_send_dsp_cmd(chip: mpu->dev, HDEX_MIDI_IN_STOP); |
64 | clear_bit(MSNDMIDI_MODE_BIT_INPUT, addr: &mpu->mode); |
65 | mpu->substream_input = NULL; |
66 | snd_msnd_disable_irq(chip: mpu->dev); |
67 | return 0; |
68 | } |
69 | |
70 | static void snd_msndmidi_input_drop(struct snd_msndmidi *mpu) |
71 | { |
72 | u16 tail; |
73 | |
74 | tail = readw(addr: mpu->dev->MIDQ + JQS_wTail); |
75 | writew(val: tail, addr: mpu->dev->MIDQ + JQS_wHead); |
76 | } |
77 | |
78 | /* |
79 | * trigger input |
80 | */ |
81 | static void snd_msndmidi_input_trigger(struct snd_rawmidi_substream *substream, |
82 | int up) |
83 | { |
84 | unsigned long flags; |
85 | struct snd_msndmidi *mpu; |
86 | |
87 | snd_printdd("snd_msndmidi_input_trigger(, %i)\n" , up); |
88 | |
89 | mpu = substream->rmidi->private_data; |
90 | spin_lock_irqsave(&mpu->input_lock, flags); |
91 | if (up) { |
92 | if (!test_and_set_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, |
93 | addr: &mpu->mode)) |
94 | snd_msndmidi_input_drop(mpu); |
95 | } else { |
96 | clear_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, addr: &mpu->mode); |
97 | } |
98 | spin_unlock_irqrestore(lock: &mpu->input_lock, flags); |
99 | if (up) |
100 | snd_msndmidi_input_read(mpu); |
101 | } |
102 | |
103 | void snd_msndmidi_input_read(void *mpuv) |
104 | { |
105 | unsigned long flags; |
106 | struct snd_msndmidi *mpu = mpuv; |
107 | void __iomem *pwMIDQData = mpu->dev->mappedbase + MIDQ_DATA_BUFF; |
108 | u16 head, tail, size; |
109 | |
110 | spin_lock_irqsave(&mpu->input_lock, flags); |
111 | head = readw(addr: mpu->dev->MIDQ + JQS_wHead); |
112 | tail = readw(addr: mpu->dev->MIDQ + JQS_wTail); |
113 | size = readw(addr: mpu->dev->MIDQ + JQS_wSize); |
114 | if (head > size || tail > size) |
115 | goto out; |
116 | while (head != tail) { |
117 | unsigned char val = readw(addr: pwMIDQData + 2 * head); |
118 | |
119 | if (test_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, &mpu->mode)) |
120 | snd_rawmidi_receive(substream: mpu->substream_input, buffer: &val, count: 1); |
121 | if (++head > size) |
122 | head = 0; |
123 | writew(val: head, addr: mpu->dev->MIDQ + JQS_wHead); |
124 | } |
125 | out: |
126 | spin_unlock_irqrestore(lock: &mpu->input_lock, flags); |
127 | } |
128 | EXPORT_SYMBOL(snd_msndmidi_input_read); |
129 | |
130 | static const struct snd_rawmidi_ops snd_msndmidi_input = { |
131 | .open = snd_msndmidi_input_open, |
132 | .close = snd_msndmidi_input_close, |
133 | .trigger = snd_msndmidi_input_trigger, |
134 | }; |
135 | |
136 | static void snd_msndmidi_free(struct snd_rawmidi *rmidi) |
137 | { |
138 | struct snd_msndmidi *mpu = rmidi->private_data; |
139 | kfree(objp: mpu); |
140 | } |
141 | |
142 | int snd_msndmidi_new(struct snd_card *card, int device) |
143 | { |
144 | struct snd_msnd *chip = card->private_data; |
145 | struct snd_msndmidi *mpu; |
146 | struct snd_rawmidi *rmidi; |
147 | int err; |
148 | |
149 | err = snd_rawmidi_new(card, id: "MSND-MIDI" , device, output_count: 1, input_count: 1, rmidi: &rmidi); |
150 | if (err < 0) |
151 | return err; |
152 | mpu = kzalloc(size: sizeof(*mpu), GFP_KERNEL); |
153 | if (mpu == NULL) { |
154 | snd_device_free(card, device_data: rmidi); |
155 | return -ENOMEM; |
156 | } |
157 | mpu->dev = chip; |
158 | chip->msndmidi_mpu = mpu; |
159 | rmidi->private_data = mpu; |
160 | rmidi->private_free = snd_msndmidi_free; |
161 | spin_lock_init(&mpu->input_lock); |
162 | strcpy(p: rmidi->name, q: "MSND MIDI" ); |
163 | snd_rawmidi_set_ops(rmidi, stream: SNDRV_RAWMIDI_STREAM_INPUT, |
164 | ops: &snd_msndmidi_input); |
165 | rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT; |
166 | return 0; |
167 | } |
168 | |