sound/firewire/fireface/amdtp-ff.c

   1 /*
   2  * amdtp-ff.c - a part of driver for RME Fireface series
   3  *
   4  * Copyright (c) 2015-2017 Takashi Sakamoto
   5  *
   6  * Licensed under the terms of the GNU General Public License, version 2.
   7  */
   8
   9 #include <sound/pcm.h>
  10 #include "ff.h"
  11
  12 struct amdtp_ff {
  13         unsigned int pcm_channels;
  14 };
  15
  16 int amdtp_ff_set_parameters(struct amdtp_stream *s, unsigned int rate,
  17                             unsigned int pcm_channels)
  18 {
  19         struct amdtp_ff *p = s->protocol;
  20         unsigned int data_channels;
  21
  22         if (amdtp_stream_running(s))
  23                 return -EBUSY;
  24
  25         p->pcm_channels = pcm_channels;
  26         data_channels = pcm_channels;
  27
  28         return amdtp_stream_set_parameters(s, rate, data_channels);
  29 }
  30
  31 static void write_pcm_s32(struct amdtp_stream *s,
  32                           struct snd_pcm_substream *pcm,
  33                           __le32 *buffer, unsigned int frames)
  34 {
  35         struct amdtp_ff *p = s->protocol;
  36         struct snd_pcm_runtime *runtime = pcm->runtime;
  37         unsigned int channels, remaining_frames, i, c;
  38         const u32 *src;
  39
  40         channels = p->pcm_channels;
  41         src = (void *)runtime->dma_area +
  42                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
  43         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
  44
  45         for (i = 0; i < frames; ++i) {
  46                 for (c = 0; c < channels; ++c) {
  47                         buffer[c] = cpu_to_le32(*src);
  48                         src++;
  49                 }
  50                 buffer += s->data_block_quadlets;
  51                 if (--remaining_frames == 0)
  52                         src = (void *)runtime->dma_area;
  53         }
  54 }
  55
  56 static void read_pcm_s32(struct amdtp_stream *s,
  57                          struct snd_pcm_substream *pcm,
  58                          __le32 *buffer, unsigned int frames)
  59 {
  60         struct amdtp_ff *p = s->protocol;
  61         struct snd_pcm_runtime *runtime = pcm->runtime;
  62         unsigned int channels, remaining_frames, i, c;
  63         u32 *dst;
  64
  65         channels = p->pcm_channels;
  66         dst  = (void *)runtime->dma_area +
  67                         frames_to_bytes(runtime, s->pcm_buffer_pointer);
  68         remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
  69
  70         for (i = 0; i < frames; ++i) {
  71                 for (c = 0; c < channels; ++c) {
  72                         *dst = le32_to_cpu(buffer[c]) & 0xffffff00;
  73                         dst++;
  74                 }
  75                 buffer += s->data_block_quadlets;
  76                 if (--remaining_frames == 0)
  77                         dst = (void *)runtime->dma_area;
  78         }
  79 }
  80
  81 static void write_pcm_silence(struct amdtp_stream *s,
  82                               __le32 *buffer, unsigned int frames)
  83 {
  84         struct amdtp_ff *p = s->protocol;
  85         unsigned int i, c, channels = p->pcm_channels;
  86
  87         for (i = 0; i < frames; ++i) {
  88                 for (c = 0; c < channels; ++c)
  89                         buffer[c] = cpu_to_le32(0x00000000);
  90                 buffer += s->data_block_quadlets;
  91         }
  92 }
  93
  94 int amdtp_ff_add_pcm_hw_constraints(struct amdtp_stream *s,
  95                                     struct snd_pcm_runtime *runtime)
  96 {
  97         int err;
  98
  99         err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
 100         if (err < 0)
 101                 return err;
 102
 103         return amdtp_stream_add_pcm_hw_constraints(s, runtime);
 104 }
 105
 106 static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
 107                                            __be32 *buffer,
 108                                            unsigned int data_blocks,
 109                                            unsigned int *syt)
 110 {
 111         struct snd_pcm_substream *pcm = READ_ONCE(s->pcm);
 112         unsigned int pcm_frames;
 113
 114         if (pcm) {
 115                 write_pcm_s32(s, pcm, (__le32 *)buffer, data_blocks);
 116                 pcm_frames = data_blocks;
 117         } else {
 118                 write_pcm_silence(s, (__le32 *)buffer, data_blocks);
 119                 pcm_frames = 0;
 120         }
 121
 122         return pcm_frames;
 123 }
 124
 125 static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
 126                                            __be32 *buffer,
 127                                            unsigned int data_blocks,
 128                                            unsigned int *syt)
 129 {
 130         struct snd_pcm_substream *pcm = READ_ONCE(s->pcm);
 131         unsigned int pcm_frames;
 132
 133         if (pcm) {
 134                 read_pcm_s32(s, pcm, (__le32 *)buffer, data_blocks);
 135                 pcm_frames = data_blocks;
 136         } else {
 137                 pcm_frames = 0;
 138         }
 139
 140         return pcm_frames;
 141 }
 142
 143 int amdtp_ff_init(struct amdtp_stream *s, struct fw_unit *unit,
 144                   enum amdtp_stream_direction dir)
 145 {
 146         amdtp_stream_process_data_blocks_t process_data_blocks;
 147
 148         if (dir == AMDTP_IN_STREAM)
 149                 process_data_blocks = process_tx_data_blocks;
 150         else
 151                 process_data_blocks = process_rx_data_blocks;
 152
 153         return amdtp_stream_init(s, unit, dir, CIP_NO_HEADER, 0,
 154                                  process_data_blocks, sizeof(struct amdtp_ff));
 155 }