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,
31 			  struct snd_pcm_substream *pcm,
32 			  __le32 *buffer, unsigned int frames)
33 {
34 	struct amdtp_ff *p = s->protocol;
35 	struct snd_pcm_runtime *runtime = pcm->runtime;
36 	unsigned int channels, remaining_frames, i, c;
37 	const u32 *src;
38 
39 	channels = p->pcm_channels;
40 	src = (void *)runtime->dma_area +
41 			frames_to_bytes(runtime, s->pcm_buffer_pointer);
42 	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
43 
44 	for (i = 0; i < frames; ++i) {
45 		for (c = 0; c < channels; ++c) {
46 			buffer[c] = cpu_to_le32(*src);
47 			src++;
48 		}
49 		buffer += s->data_block_quadlets;
50 		if (--remaining_frames == 0)
51 			src = (void *)runtime->dma_area;
52 	}
53 }
54 
55 static void read_pcm_s32(struct amdtp_stream *s,
56 			 struct snd_pcm_substream *pcm,
57 			 __le32 *buffer, unsigned int frames)
58 {
59 	struct amdtp_ff *p = s->protocol;
60 	struct snd_pcm_runtime *runtime = pcm->runtime;
61 	unsigned int channels, remaining_frames, i, c;
62 	u32 *dst;
63 
64 	channels = p->pcm_channels;
65 	dst  = (void *)runtime->dma_area +
66 			frames_to_bytes(runtime, s->pcm_buffer_pointer);
67 	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
68 
69 	for (i = 0; i < frames; ++i) {
70 		for (c = 0; c < channels; ++c) {
71 			*dst = le32_to_cpu(buffer[c]) & 0xffffff00;
72 			dst++;
73 		}
74 		buffer += s->data_block_quadlets;
75 		if (--remaining_frames == 0)
76 			dst = (void *)runtime->dma_area;
77 	}
78 }
79 
80 static void write_pcm_silence(struct amdtp_stream *s,
81 			      __le32 *buffer, unsigned int frames)
82 {
83 	struct amdtp_ff *p = s->protocol;
84 	unsigned int i, c, channels = p->pcm_channels;
85 
86 	for (i = 0; i < frames; ++i) {
87 		for (c = 0; c < channels; ++c)
88 			buffer[c] = cpu_to_le32(0x00000000);
89 		buffer += s->data_block_quadlets;
90 	}
91 }
92 
93 int amdtp_ff_add_pcm_hw_constraints(struct amdtp_stream *s,
94 				    struct snd_pcm_runtime *runtime)
95 {
96 	int err;
97 
98 	err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
99 	if (err < 0)
100 		return err;
101 
102 	return amdtp_stream_add_pcm_hw_constraints(s, runtime);
103 }
104 
105 static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
106 					   __be32 *buffer,
107 					   unsigned int data_blocks,
108 					   unsigned int *syt)
109 {
110 	struct snd_pcm_substream *pcm = READ_ONCE(s->pcm);
111 	unsigned int pcm_frames;
112 
113 	if (pcm) {
114 		write_pcm_s32(s, pcm, (__le32 *)buffer, data_blocks);
115 		pcm_frames = data_blocks;
116 	} else {
117 		write_pcm_silence(s, (__le32 *)buffer, data_blocks);
118 		pcm_frames = 0;
119 	}
120 
121 	return pcm_frames;
122 }
123 
124 static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
125 					   __be32 *buffer,
126 					   unsigned int data_blocks,
127 					   unsigned int *syt)
128 {
129 	struct snd_pcm_substream *pcm = READ_ONCE(s->pcm);
130 	unsigned int pcm_frames;
131 
132 	if (pcm) {
133 		read_pcm_s32(s, pcm, (__le32 *)buffer, data_blocks);
134 		pcm_frames = data_blocks;
135 	} else {
136 		pcm_frames = 0;
137 	}
138 
139 	return pcm_frames;
140 }
141 
142 int amdtp_ff_init(struct amdtp_stream *s, struct fw_unit *unit,
143 		  enum amdtp_stream_direction dir)
144 {
145 	amdtp_stream_process_data_blocks_t process_data_blocks;
146 
147 	if (dir == AMDTP_IN_STREAM)
148 		process_data_blocks = process_tx_data_blocks;
149 	else
150 		process_data_blocks = process_rx_data_blocks;
151 
152 	return amdtp_stream_init(s, unit, dir, CIP_NO_HEADER, 0,
153 				 process_data_blocks, sizeof(struct amdtp_ff));
154 }
155