xref: /linux/sound/firewire/fireface/amdtp-ff.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * amdtp-ff.c - a part of driver for RME Fireface series
4  *
5  * Copyright (c) 2015-2017 Takashi Sakamoto
6  */
7 
8 #include <sound/pcm.h>
9 #include "ff.h"
10 
11 struct amdtp_ff {
12 	unsigned int pcm_channels;
13 };
14 
15 int amdtp_ff_set_parameters(struct amdtp_stream *s, unsigned int rate,
16 			    unsigned int pcm_channels)
17 {
18 	struct amdtp_ff *p = s->protocol;
19 	unsigned int data_channels;
20 
21 	if (amdtp_stream_running(s))
22 		return -EBUSY;
23 
24 	p->pcm_channels = pcm_channels;
25 	data_channels = pcm_channels;
26 
27 	return amdtp_stream_set_parameters(s, rate, data_channels);
28 }
29 
30 static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
31 			  __le32 *buffer, unsigned int frames,
32 			  unsigned int pcm_frames)
33 {
34 	struct amdtp_ff *p = s->protocol;
35 	unsigned int channels = p->pcm_channels;
36 	struct snd_pcm_runtime *runtime = pcm->runtime;
37 	unsigned int pcm_buffer_pointer;
38 	int remaining_frames;
39 	const u32 *src;
40 	int i, c;
41 
42 	pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
43 	pcm_buffer_pointer %= runtime->buffer_size;
44 
45 	src = (void *)runtime->dma_area +
46 				frames_to_bytes(runtime, pcm_buffer_pointer);
47 	remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
48 
49 	for (i = 0; i < frames; ++i) {
50 		for (c = 0; c < channels; ++c) {
51 			buffer[c] = cpu_to_le32(*src);
52 			src++;
53 		}
54 		buffer += s->data_block_quadlets;
55 		if (--remaining_frames == 0)
56 			src = (void *)runtime->dma_area;
57 	}
58 }
59 
60 static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
61 			 __le32 *buffer, unsigned int frames,
62 			 unsigned int pcm_frames)
63 {
64 	struct amdtp_ff *p = s->protocol;
65 	unsigned int channels = p->pcm_channels;
66 	struct snd_pcm_runtime *runtime = pcm->runtime;
67 	unsigned int pcm_buffer_pointer;
68 	int remaining_frames;
69 	u32 *dst;
70 	int i, c;
71 
72 	pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
73 	pcm_buffer_pointer %= runtime->buffer_size;
74 
75 	dst  = (void *)runtime->dma_area +
76 				frames_to_bytes(runtime, pcm_buffer_pointer);
77 	remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
78 
79 	for (i = 0; i < frames; ++i) {
80 		for (c = 0; c < channels; ++c) {
81 			*dst = le32_to_cpu(buffer[c]) & 0xffffff00;
82 			dst++;
83 		}
84 		buffer += s->data_block_quadlets;
85 		if (--remaining_frames == 0)
86 			dst = (void *)runtime->dma_area;
87 	}
88 }
89 
90 static void write_pcm_silence(struct amdtp_stream *s,
91 			      __le32 *buffer, unsigned int frames)
92 {
93 	struct amdtp_ff *p = s->protocol;
94 	unsigned int i, c, channels = p->pcm_channels;
95 
96 	for (i = 0; i < frames; ++i) {
97 		for (c = 0; c < channels; ++c)
98 			buffer[c] = cpu_to_le32(0x00000000);
99 		buffer += s->data_block_quadlets;
100 	}
101 }
102 
103 int amdtp_ff_add_pcm_hw_constraints(struct amdtp_stream *s,
104 				    struct snd_pcm_runtime *runtime)
105 {
106 	int err;
107 
108 	err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
109 	if (err < 0)
110 		return err;
111 
112 	return amdtp_stream_add_pcm_hw_constraints(s, runtime);
113 }
114 
115 static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
116 					   const struct pkt_desc *descs,
117 					   unsigned int packets,
118 					   struct snd_pcm_substream *pcm)
119 {
120 	unsigned int pcm_frames = 0;
121 	int i;
122 
123 	for (i = 0; i < packets; ++i) {
124 		const struct pkt_desc *desc = descs + i;
125 		__le32 *buf = (__le32 *)desc->ctx_payload;
126 		unsigned int data_blocks = desc->data_blocks;
127 
128 		if (pcm) {
129 			write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
130 			pcm_frames += data_blocks;
131 		} else {
132 			write_pcm_silence(s, buf, data_blocks);
133 		}
134 	}
135 
136 	return pcm_frames;
137 }
138 
139 static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
140 					    const struct pkt_desc *descs,
141 					    unsigned int packets,
142 					    struct snd_pcm_substream *pcm)
143 {
144 	unsigned int pcm_frames = 0;
145 	int i;
146 
147 	for (i = 0; i < packets; ++i) {
148 		const struct pkt_desc *desc = descs + i;
149 		__le32 *buf = (__le32 *)desc->ctx_payload;
150 		unsigned int data_blocks = desc->data_blocks;
151 
152 		if (pcm) {
153 			read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
154 			pcm_frames += data_blocks;
155 		}
156 	}
157 
158 	return pcm_frames;
159 }
160 
161 int amdtp_ff_init(struct amdtp_stream *s, struct fw_unit *unit,
162 		  enum amdtp_stream_direction dir)
163 {
164 	amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
165 
166 	if (dir == AMDTP_IN_STREAM)
167 		process_ctx_payloads = process_ir_ctx_payloads;
168 	else
169 		process_ctx_payloads = process_it_ctx_payloads;
170 
171 	return amdtp_stream_init(s, unit, dir, CIP_NO_HEADER, 0,
172 				 process_ctx_payloads, sizeof(struct amdtp_ff));
173 }
174