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
11struct amdtp_ff {
12	unsigned int pcm_channels;
13};
14
15int 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, 1);
28}
29
30static 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
60static 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
90static 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
103int 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
115static void process_it_ctx_payloads(struct amdtp_stream *s, const struct pkt_desc *desc,
116				    unsigned int count, struct snd_pcm_substream *pcm)
117{
118	unsigned int pcm_frames = 0;
119	int i;
120
121	for (i = 0; i < count; ++i) {
122		__le32 *buf = (__le32 *)desc->ctx_payload;
123		unsigned int data_blocks = desc->data_blocks;
124
125		if (pcm) {
126			write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
127			pcm_frames += data_blocks;
128		} else {
129			write_pcm_silence(s, buf, data_blocks);
130		}
131
132		desc = amdtp_stream_next_packet_desc(s, desc);
133	}
134}
135
136static void process_ir_ctx_payloads(struct amdtp_stream *s, const struct pkt_desc *desc,
137				    unsigned int count, struct snd_pcm_substream *pcm)
138{
139	unsigned int pcm_frames = 0;
140	int i;
141
142	for (i = 0; i < count; ++i) {
143		__le32 *buf = (__le32 *)desc->ctx_payload;
144		unsigned int data_blocks = desc->data_blocks;
145
146		if (pcm) {
147			read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
148			pcm_frames += data_blocks;
149		}
150
151		desc = amdtp_stream_next_packet_desc(s, desc);
152	}
153}
154
155int amdtp_ff_init(struct amdtp_stream *s, struct fw_unit *unit,
156		  enum amdtp_stream_direction dir)
157{
158	amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
159
160	if (dir == AMDTP_IN_STREAM)
161		process_ctx_payloads = process_ir_ctx_payloads;
162	else
163		process_ctx_payloads = process_it_ctx_payloads;
164
165	return amdtp_stream_init(s, unit, dir, CIP_BLOCKING | CIP_UNAWARE_SYT | CIP_NO_HEADER, 0,
166				 process_ctx_payloads, sizeof(struct amdtp_ff));
167}
168