[PATCH 1/2] ALSA: pcm: add SNDRV_PCM_FORMAT_{S,U}20_4

From: Maciej S. Szmigiero
Date: Wed Nov 22 2017 - 14:17:49 EST


This format is similar to existing SNDRV_PCM_FORMAT_{S,U}20_3 that keep
20-bit PCM samples in 3 bytes, however i.MX6 platform SSI FIFO does not
allow 3-byte accesses (including DMA) so a 4-byte format is needed for it.

Signed-off-by: Maciej S. Szmigiero <mail@xxxxxxxxxxxxxxxxxxxxx>
---
include/sound/pcm.h | 8 ++++++++
include/sound/soc-dai.h | 2 ++
include/uapi/sound/asound.h | 10 +++++++++-
sound/core/pcm_misc.c | 16 ++++++++++++++++
4 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index 24febf9e177c..7ad2d3f0934f 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -191,6 +191,10 @@ struct snd_pcm_ops {
#define SNDRV_PCM_FMTBIT_DSD_U32_LE _SNDRV_PCM_FMTBIT(DSD_U32_LE)
#define SNDRV_PCM_FMTBIT_DSD_U16_BE _SNDRV_PCM_FMTBIT(DSD_U16_BE)
#define SNDRV_PCM_FMTBIT_DSD_U32_BE _SNDRV_PCM_FMTBIT(DSD_U32_BE)
+#define SNDRV_PCM_FMTBIT_S20_4LE _SNDRV_PCM_FMTBIT(S20_4LE)
+#define SNDRV_PCM_FMTBIT_U20_4LE _SNDRV_PCM_FMTBIT(U20_4LE)
+#define SNDRV_PCM_FMTBIT_S20_4BE _SNDRV_PCM_FMTBIT(S20_4BE)
+#define SNDRV_PCM_FMTBIT_U20_4BE _SNDRV_PCM_FMTBIT(U20_4BE)

#ifdef SNDRV_LITTLE_ENDIAN
#define SNDRV_PCM_FMTBIT_S16 SNDRV_PCM_FMTBIT_S16_LE
@@ -202,6 +206,8 @@ struct snd_pcm_ops {
#define SNDRV_PCM_FMTBIT_FLOAT SNDRV_PCM_FMTBIT_FLOAT_LE
#define SNDRV_PCM_FMTBIT_FLOAT64 SNDRV_PCM_FMTBIT_FLOAT64_LE
#define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE
+#define SNDRV_PCM_FMTBIT_S20_4 SNDRV_PCM_FMTBIT_S20_4LE
+#define SNDRV_PCM_FMTBIT_U20_4 SNDRV_PCM_FMTBIT_U20_4LE
#endif
#ifdef SNDRV_BIG_ENDIAN
#define SNDRV_PCM_FMTBIT_S16 SNDRV_PCM_FMTBIT_S16_BE
@@ -213,6 +219,8 @@ struct snd_pcm_ops {
#define SNDRV_PCM_FMTBIT_FLOAT SNDRV_PCM_FMTBIT_FLOAT_BE
#define SNDRV_PCM_FMTBIT_FLOAT64 SNDRV_PCM_FMTBIT_FLOAT64_BE
#define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE
+#define SNDRV_PCM_FMTBIT_S20_4 SNDRV_PCM_FMTBIT_S20_4BE
+#define SNDRV_PCM_FMTBIT_U20_4 SNDRV_PCM_FMTBIT_U20_4BE
#endif

struct snd_pcm_file {
diff --git a/include/sound/soc-dai.h b/include/sound/soc-dai.h
index 58acd00cae19..16aec0cc96f5 100644
--- a/include/sound/soc-dai.h
+++ b/include/sound/soc-dai.h
@@ -102,6 +102,8 @@ struct snd_compr_stream;
SNDRV_PCM_FMTBIT_S16_BE |\
SNDRV_PCM_FMTBIT_S20_3LE |\
SNDRV_PCM_FMTBIT_S20_3BE |\
+ SNDRV_PCM_FMTBIT_S20_4LE |\
+ SNDRV_PCM_FMTBIT_S20_4BE |\
SNDRV_PCM_FMTBIT_S24_3LE |\
SNDRV_PCM_FMTBIT_S24_3BE |\
SNDRV_PCM_FMTBIT_S32_LE |\
diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h
index c227ccba60ae..69b661816491 100644
--- a/include/uapi/sound/asound.h
+++ b/include/uapi/sound/asound.h
@@ -236,7 +236,11 @@ typedef int __bitwise snd_pcm_format_t;
#define SNDRV_PCM_FORMAT_DSD_U32_LE ((__force snd_pcm_format_t) 50) /* DSD, 4-byte samples DSD (x32), little endian */
#define SNDRV_PCM_FORMAT_DSD_U16_BE ((__force snd_pcm_format_t) 51) /* DSD, 2-byte samples DSD (x16), big endian */
#define SNDRV_PCM_FORMAT_DSD_U32_BE ((__force snd_pcm_format_t) 52) /* DSD, 4-byte samples DSD (x32), big endian */
-#define SNDRV_PCM_FORMAT_LAST SNDRV_PCM_FORMAT_DSD_U32_BE
+#define SNDRV_PCM_FORMAT_S20_4LE ((__force snd_pcm_format_t) 53) /* in four bytes */
+#define SNDRV_PCM_FORMAT_S20_4BE ((__force snd_pcm_format_t) 54) /* in four bytes */
+#define SNDRV_PCM_FORMAT_U20_4LE ((__force snd_pcm_format_t) 55) /* in four bytes */
+#define SNDRV_PCM_FORMAT_U20_4BE ((__force snd_pcm_format_t) 56) /* in four bytes */
+#define SNDRV_PCM_FORMAT_LAST SNDRV_PCM_FORMAT_U20_4BE

#ifdef SNDRV_LITTLE_ENDIAN
#define SNDRV_PCM_FORMAT_S16 SNDRV_PCM_FORMAT_S16_LE
@@ -248,6 +252,8 @@ typedef int __bitwise snd_pcm_format_t;
#define SNDRV_PCM_FORMAT_FLOAT SNDRV_PCM_FORMAT_FLOAT_LE
#define SNDRV_PCM_FORMAT_FLOAT64 SNDRV_PCM_FORMAT_FLOAT64_LE
#define SNDRV_PCM_FORMAT_IEC958_SUBFRAME SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
+#define SNDRV_PCM_FORMAT_S20_4 SNDRV_PCM_FORMAT_S20_4LE
+#define SNDRV_PCM_FORMAT_U20_4 SNDRV_PCM_FORMAT_U20_4LE
#endif
#ifdef SNDRV_BIG_ENDIAN
#define SNDRV_PCM_FORMAT_S16 SNDRV_PCM_FORMAT_S16_BE
@@ -259,6 +265,8 @@ typedef int __bitwise snd_pcm_format_t;
#define SNDRV_PCM_FORMAT_FLOAT SNDRV_PCM_FORMAT_FLOAT_BE
#define SNDRV_PCM_FORMAT_FLOAT64 SNDRV_PCM_FORMAT_FLOAT64_BE
#define SNDRV_PCM_FORMAT_IEC958_SUBFRAME SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE
+#define SNDRV_PCM_FORMAT_S20_4 SNDRV_PCM_FORMAT_S20_4BE
+#define SNDRV_PCM_FORMAT_U20_4 SNDRV_PCM_FORMAT_U20_4BE
#endif

typedef int __bitwise snd_pcm_subformat_t;
diff --git a/sound/core/pcm_misc.c b/sound/core/pcm_misc.c
index 9be81025372f..132ee41edae1 100644
--- a/sound/core/pcm_misc.c
+++ b/sound/core/pcm_misc.c
@@ -229,6 +229,22 @@ static struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = {
.width = 5, .phys = 8, .le = -1, .signd = -1,
.silence = {},
},
+ [SNDRV_PCM_FORMAT_S20_4LE] = {
+ .width = 20, .phys = 32, .le = 1, .signd = 1,
+ .silence = {},
+ },
+ [SNDRV_PCM_FORMAT_S20_4BE] = {
+ .width = 20, .phys = 32, .le = 0, .signd = 1,
+ .silence = {},
+ },
+ [SNDRV_PCM_FORMAT_U20_4LE] = {
+ .width = 20, .phys = 32, .le = 1, .signd = 0,
+ .silence = { 0x00, 0x00, 0x08, 0x00 },
+ },
+ [SNDRV_PCM_FORMAT_U20_4BE] = {
+ .width = 20, .phys = 32, .le = 0, .signd = 0,
+ .silence = { 0x00, 0x08, 0x00, 0x00 },
+ },
};