summaryrefslogtreecommitdiffstats
path: root/sound/firewire/fireface/ff-protocol-ff800.c
blob: 2acbf60397700bc5d224088538ede9771fef5b8a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
/*
 * ff-protocol-ff800.c - a part of driver for RME Fireface series
 *
 * Copyright (c) 2018 Takashi Sakamoto
 *
 * Licensed under the terms of the GNU General Public License, version 2.
 */

#include <linux/delay.h>

#include "ff.h"

#define FF800_STF		0x0000fc88f000
#define FF800_RX_PACKET_FORMAT	0x0000fc88f004
#define FF800_ALLOC_TX_STREAM	0x0000fc88f008
#define FF800_ISOC_COMM_START	0x0000fc88f00c
#define   FF800_TX_S800_FLAG	0x00000800
#define FF800_ISOC_COMM_STOP	0x0000fc88f010

#define FF800_TX_PACKET_ISOC_CH	0x0000801c0008

static int allocate_rx_resources(struct snd_ff *ff)
{
	u32 data;
	__le32 reg;
	int err;

	// Controllers should allocate isochronous resources for rx stream.
	err = fw_iso_resources_allocate(&ff->rx_resources,
				amdtp_stream_get_max_payload(&ff->rx_stream),
				fw_parent_device(ff->unit)->max_speed);
	if (err < 0)
		return err;

	// Set isochronous channel and the number of quadlets of rx packets.
	data = ff->rx_stream.data_block_quadlets << 3;
	data = (data << 8) | ff->rx_resources.channel;
	reg = cpu_to_le32(data);
	return snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
				FF800_RX_PACKET_FORMAT, &reg, sizeof(reg), 0);
}

static int allocate_tx_resources(struct snd_ff *ff)
{
	__le32 reg;
	unsigned int count;
	unsigned int tx_isoc_channel;
	int err;

	reg = cpu_to_le32(ff->tx_stream.data_block_quadlets);
	err = snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
				 FF800_ALLOC_TX_STREAM, &reg, sizeof(reg), 0);
	if (err < 0)
		return err;

	// Wait till the format of tx packet is available.
	count = 0;
	while (count++ < 10) {
		u32 data;
		err = snd_fw_transaction(ff->unit, TCODE_READ_QUADLET_REQUEST,
				FF800_TX_PACKET_ISOC_CH, &reg, sizeof(reg), 0);
		if (err < 0)
			return err;

		data = le32_to_cpu(reg);
		if (data != 0xffffffff) {
			tx_isoc_channel = data;
			break;
		}

		msleep(50);
	}
	if (count >= 10)
		return -ETIMEDOUT;

	// NOTE: this is a makeshift to start OHCI 1394 IR context in the
	// channel. On the other hand, 'struct fw_iso_resources.allocated' is
	// not true and it's not deallocated at stop.
	ff->tx_resources.channel = tx_isoc_channel;

	return 0;
}

static int ff800_begin_session(struct snd_ff *ff, unsigned int rate)
{
	__le32 reg;
	int err;

	reg = cpu_to_le32(rate);
	err = snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
				 FF800_STF, &reg, sizeof(reg), 0);
	if (err < 0)
		return err;

	// If starting isochronous communication immediately, change of STF has
	// no effect. In this case, the communication runs based on former STF.
	// Let's sleep for a bit.
	msleep(100);

	err = allocate_rx_resources(ff);
	if (err < 0)
		return err;

	err = allocate_tx_resources(ff);
	if (err < 0)
		return err;

	reg = cpu_to_le32(0x80000000);
	reg |= cpu_to_le32(ff->tx_stream.data_block_quadlets);
	if (fw_parent_device(ff->unit)->max_speed == SCODE_800)
		reg |= cpu_to_le32(FF800_TX_S800_FLAG);
	return snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
				 FF800_ISOC_COMM_START, &reg, sizeof(reg), 0);
}

static void ff800_finish_session(struct snd_ff *ff)
{
	__le32 reg;

	reg = cpu_to_le32(0x80000000);
	snd_fw_transaction(ff->unit, TCODE_WRITE_QUADLET_REQUEST,
			   FF800_ISOC_COMM_STOP, &reg, sizeof(reg), 0);
}

static void ff800_handle_midi_msg(struct snd_ff *ff, __le32 *buf, size_t length)
{
	int i;

	for (i = 0; i < length / 4; i++) {
		u8 byte = le32_to_cpu(buf[i]) & 0xff;
		struct snd_rawmidi_substream *substream;

		substream = READ_ONCE(ff->tx_midi_substreams[0]);
		if (substream)
			snd_rawmidi_receive(substream, &byte, 1);
	}
}

const struct snd_ff_protocol snd_ff_protocol_ff800 = {
	.handle_midi_msg	= ff800_handle_midi_msg,
	.begin_session		= ff800_begin_session,
	.finish_session		= ff800_finish_session,
};