1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * motu-transaction.c - a part of driver for MOTU FireWire series
4 *
5 * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
6 */
7
8
9 #include "motu.h"
10
11 #define SND_MOTU_ADDR_BASE 0xfffff0000000ULL
12 #define ASYNC_ADDR_HI 0x0b04
13 #define ASYNC_ADDR_LO 0x0b08
14
15 int snd_motu_transaction_read(struct snd_motu *motu, u32 offset, __be32 *reg,
16 size_t size)
17 {
18 int tcode;
19
20 if (size % sizeof(__be32) > 0 || size <= 0)
21 return -EINVAL;
22 if (size == sizeof(__be32))
23 tcode = TCODE_READ_QUADLET_REQUEST;
24 else
25 tcode = TCODE_READ_BLOCK_REQUEST;
26
27 return snd_fw_transaction(motu->unit, tcode,
28 SND_MOTU_ADDR_BASE + offset, reg, size, 0);
29 }
30
31 int snd_motu_transaction_write(struct snd_motu *motu, u32 offset, __be32 *reg,
32 size_t size)
33 {
34 int tcode;
35
36 if (size % sizeof(__be32) > 0 || size <= 0)
37 return -EINVAL;
38 if (size == sizeof(__be32))
39 tcode = TCODE_WRITE_QUADLET_REQUEST;
40 else
41 tcode = TCODE_WRITE_BLOCK_REQUEST;
42
43 return snd_fw_transaction(motu->unit, tcode,
44 SND_MOTU_ADDR_BASE + offset, reg, size, 0);
45 }
46
47 static void handle_message(struct fw_card *card, struct fw_request *request,
48 int tcode, int destination, int source,
49 int generation, unsigned long long offset,
50 void *data, size_t length, void *callback_data)
51 {
52 struct snd_motu *motu = callback_data;
53 __be32 *buf = (__be32 *)data;
54 unsigned long flags;
55
56 if (tcode != TCODE_WRITE_QUADLET_REQUEST) {
57 fw_send_response(card, request, RCODE_COMPLETE);
58 return;
59 }
60
61 if (offset != motu->async_handler.offset || length != 4) {
62 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
63 return;
64 }
65
66 spin_lock_irqsave(&motu->lock, flags);
67 motu->msg = be32_to_cpu(*buf);
68 spin_unlock_irqrestore(&motu->lock, flags);
69
70 fw_send_response(card, request, RCODE_COMPLETE);
71
72 wake_up(&motu->hwdep_wait);
73 }
74
75 int snd_motu_transaction_reregister(struct snd_motu *motu)
76 {
77 struct fw_device *device = fw_parent_device(motu->unit);
78 __be32 data;
79 int err;
80
81 if (motu->async_handler.callback_data == NULL)
82 return -EINVAL;
83
84 /* Register messaging address. Block transaction is not allowed. */
85 data = cpu_to_be32((device->card->node_id << 16) |
86 (motu->async_handler.offset >> 32));
87 err = snd_motu_transaction_write(motu, ASYNC_ADDR_HI, &data,
88 sizeof(data));
89 if (err < 0)
90 return err;
91
92 data = cpu_to_be32(motu->async_handler.offset);
93 return snd_motu_transaction_write(motu, ASYNC_ADDR_LO, &data,
94 sizeof(data));
95 }
96
97 int snd_motu_transaction_register(struct snd_motu *motu)
98 {
99 static const struct fw_address_region resp_register_region = {
100 .start = 0xffffe0000000ull,
101 .end = 0xffffe000ffffull,
102 };
103 int err;
104
105 /* Perhaps, 4 byte messages are transferred. */
106 motu->async_handler.length = 4;
107 motu->async_handler.address_callback = handle_message;
108 motu->async_handler.callback_data = motu;
109
110 err = fw_core_add_address_handler(&motu->async_handler,
111 &resp_register_region);
112 if (err < 0)
113 return err;
114
115 err = snd_motu_transaction_reregister(motu);
116 if (err < 0) {
117 fw_core_remove_address_handler(&motu->async_handler);
118 motu->async_handler.address_callback = NULL;
119 }
120
121 return err;
122 }
123
124 void snd_motu_transaction_unregister(struct snd_motu *motu)
125 {
126 __be32 data;
127
128 if (motu->async_handler.address_callback != NULL)
129 fw_core_remove_address_handler(&motu->async_handler);
130 motu->async_handler.address_callback = NULL;
131
132 /* Unregister the address. */
133 data = cpu_to_be32(0x00000000);
134 snd_motu_transaction_write(motu, ASYNC_ADDR_HI, &data, sizeof(data));
135 snd_motu_transaction_write(motu, ASYNC_ADDR_LO, &data, sizeof(data));
136 }
137
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