tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
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
15int 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
31int 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
47static 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
55 if (tcode != TCODE_WRITE_QUADLET_REQUEST) {
56 fw_send_response(card, request, RCODE_COMPLETE);
57 return;
58 }
59
60 if (offset != motu->async_handler.offset || length != 4) {
61 fw_send_response(card, request, RCODE_ADDRESS_ERROR);
62 return;
63 }
64
65 scoped_guard(spinlock_irqsave, &motu->lock) {
66 motu->msg = be32_to_cpu(*buf);
67 }
68
69 fw_send_response(card, request, RCODE_COMPLETE);
70
71 wake_up(&motu->hwdep_wait);
72}
73
74int snd_motu_transaction_reregister(struct snd_motu *motu)
75{
76 struct fw_device *device = fw_parent_device(motu->unit);
77 __be32 data;
78 int err;
79
80 if (motu->async_handler.callback_data == NULL)
81 return -EINVAL;
82
83 /* Register messaging address. Block transaction is not allowed. */
84 data = cpu_to_be32((device->card->node_id << 16) |
85 (motu->async_handler.offset >> 32));
86 err = snd_motu_transaction_write(motu, ASYNC_ADDR_HI, &data,
87 sizeof(data));
88 if (err < 0)
89 return err;
90
91 data = cpu_to_be32(motu->async_handler.offset);
92 return snd_motu_transaction_write(motu, ASYNC_ADDR_LO, &data,
93 sizeof(data));
94}
95
96int snd_motu_transaction_register(struct snd_motu *motu)
97{
98 static const struct fw_address_region resp_register_region = {
99 .start = 0xffffe0000000ull,
100 .end = 0xffffe000ffffull,
101 };
102 int err;
103
104 /* Perhaps, 4 byte messages are transferred. */
105 motu->async_handler.length = 4;
106 motu->async_handler.address_callback = handle_message;
107 motu->async_handler.callback_data = motu;
108
109 err = fw_core_add_address_handler(&motu->async_handler,
110 &resp_register_region);
111 if (err < 0)
112 return err;
113
114 err = snd_motu_transaction_reregister(motu);
115 if (err < 0) {
116 fw_core_remove_address_handler(&motu->async_handler);
117 motu->async_handler.address_callback = NULL;
118 }
119
120 return err;
121}
122
123void snd_motu_transaction_unregister(struct snd_motu *motu)
124{
125 __be32 data;
126
127 if (motu->async_handler.address_callback != NULL)
128 fw_core_remove_address_handler(&motu->async_handler);
129 motu->async_handler.address_callback = NULL;
130
131 /* Unregister the address. */
132 data = cpu_to_be32(0x00000000);
133 snd_motu_transaction_write(motu, ASYNC_ADDR_HI, &data, sizeof(data));
134 snd_motu_transaction_write(motu, ASYNC_ADDR_LO, &data, sizeof(data));
135}