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authorTakashi Iwai2016-11-10 22:17:40 +0100
committerTakashi Iwai2016-11-11 17:33:16 +0100
commite732d1bcd452a040a18242d555996703465c1ca7 (patch)
tree025657f7362b67f651ca0807ffd80f425609264e
parent693ba474a39a2c22e1576995139c9bfdd8b554c8 (diff)
ASoC: doc: ReSTize DAI.txt
A simple conversion from a plain text file with slight reformatting / corrections. The file name was changed to lower letters to align with others. Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
-rw-r--r--Documentation/sound/soc/dai.rst (renamed from Documentation/sound/alsa/soc/DAI.txt)28
-rw-r--r--Documentation/sound/soc/index.rst1
2 files changed, 19 insertions, 10 deletions
diff --git a/Documentation/sound/alsa/soc/DAI.txt b/Documentation/sound/soc/dai.rst
index c9679264c559..55820e51708f 100644
--- a/Documentation/sound/alsa/soc/DAI.txt
+++ b/Documentation/sound/soc/dai.rst
@@ -1,3 +1,7 @@
+==================================
+ASoC Digital Audio Interface (DAI)
+==================================
+
ASoC currently supports the three main Digital Audio Interfaces (DAI) found on
SoC controllers and portable audio CODECs today, namely AC97, I2S and PCM.
@@ -5,21 +9,21 @@ SoC controllers and portable audio CODECs today, namely AC97, I2S and PCM.
AC97
====
- AC97 is a five wire interface commonly found on many PC sound cards. It is
+AC97 is a five wire interface commonly found on many PC sound cards. It is
now also popular in many portable devices. This DAI has a reset line and time
multiplexes its data on its SDATA_OUT (playback) and SDATA_IN (capture) lines.
The bit clock (BCLK) is always driven by the CODEC (usually 12.288MHz) and the
frame (FRAME) (usually 48kHz) is always driven by the controller. Each AC97
frame is 21uS long and is divided into 13 time slots.
-The AC97 specification can be found at :-
+The AC97 specification can be found at :
http://www.intel.com/p/en_US/business/design
I2S
===
- I2S is a common 4 wire DAI used in HiFi, STB and portable devices. The Tx and
+I2S is a common 4 wire DAI used in HiFi, STB and portable devices. The Tx and
Rx lines are used for audio transmission, whilst the bit clock (BCLK) and
left/right clock (LRC) synchronise the link. I2S is flexible in that either the
controller or CODEC can drive (master) the BCLK and LRC clock lines. Bit clock
@@ -30,13 +34,15 @@ different sample rates.
I2S has several different operating modes:-
- o I2S - MSB is transmitted on the falling edge of the first BCLK after LRC
- transition.
+I2S
+ MSB is transmitted on the falling edge of the first BCLK after LRC
+ transition.
- o Left Justified - MSB is transmitted on transition of LRC.
+Left Justified
+ MSB is transmitted on transition of LRC.
- o Right Justified - MSB is transmitted sample size BCLKs before LRC
- transition.
+Right Justified
+ MSB is transmitted sample size BCLKs before LRC transition.
PCM
===
@@ -51,6 +57,8 @@ is sometimes referred to as network mode).
Common PCM operating modes:-
- o Mode A - MSB is transmitted on falling edge of first BCLK after FRAME/SYNC.
+Mode A
+ MSB is transmitted on falling edge of first BCLK after FRAME/SYNC.
- o Mode B - MSB is transmitted on rising edge of FRAME/SYNC.
+Mode B
+ MSB is transmitted on rising edge of FRAME/SYNC.
diff --git a/Documentation/sound/soc/index.rst b/Documentation/sound/soc/index.rst
index a2e023c91df2..aea7ae7e5aad 100644
--- a/Documentation/sound/soc/index.rst
+++ b/Documentation/sound/soc/index.rst
@@ -9,3 +9,4 @@ The documentation is spilt into the following sections:-
overview
codec
+ dai