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authorMatt LaPlante <kernel1@cyberdogtech.com>2007-10-19 19:34:40 -0400
committerAdrian Bunk <bunk@kernel.org>2007-10-19 19:34:40 -0400
commit01dd2fbf0da4019c380b6ca22a074538fb31db5a (patch)
tree210291bd341c4450c8c51d8db890af0978f4035d /Documentation/sound/alsa
parent0f035b8e8491f4ff87f6eec3e3f754d36b39d7a2 (diff)
typo fixes
Most of these fixes were already submitted for old kernel versions, and were approved, but for some reason they never made it into the releases. Because this is a consolidation of a couple old missed patches, it touches both Kconfigs and documentation texts. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
Diffstat (limited to 'Documentation/sound/alsa')
-rw-r--r--Documentation/sound/alsa/soc/DAI.txt8
-rw-r--r--Documentation/sound/alsa/soc/clocking.txt10
-rw-r--r--Documentation/sound/alsa/soc/codec.txt6
-rw-r--r--Documentation/sound/alsa/soc/dapm.txt4
-rw-r--r--Documentation/sound/alsa/soc/overview.txt17
-rw-r--r--Documentation/sound/alsa/soc/platform.txt2
-rw-r--r--Documentation/sound/alsa/soc/pops_clicks.txt6
7 files changed, 27 insertions, 26 deletions
diff --git a/Documentation/sound/alsa/soc/DAI.txt b/Documentation/sound/alsa/soc/DAI.txt
index 58cbfd01ea8f..3feeb9ecdec4 100644
--- a/Documentation/sound/alsa/soc/DAI.txt
+++ b/Documentation/sound/alsa/soc/DAI.txt
@@ -20,12 +20,12 @@ I2S
20=== 20===
21 21
22 I2S is a common 4 wire DAI used in HiFi, STB and portable devices. The Tx and 22 I2S is a common 4 wire DAI used in HiFi, STB and portable devices. The Tx and
23Rx lines are used for audio transmision, whilst the bit clock (BCLK) and 23Rx lines are used for audio transmission, whilst the bit clock (BCLK) and
24left/right clock (LRC) synchronise the link. I2S is flexible in that either the 24left/right clock (LRC) synchronise the link. I2S is flexible in that either the
25controller or CODEC can drive (master) the BCLK and LRC clock lines. Bit clock 25controller or CODEC can drive (master) the BCLK and LRC clock lines. Bit clock
26usually varies depending on the sample rate and the master system clock 26usually varies depending on the sample rate and the master system clock
27(SYSCLK). LRCLK is the same as the sample rate. A few devices support separate 27(SYSCLK). LRCLK is the same as the sample rate. A few devices support separate
28ADC and DAC LRCLK's, this allows for similtanious capture and playback at 28ADC and DAC LRCLK's, this allows for simultaneous capture and playback at
29different sample rates. 29different sample rates.
30 30
31I2S has several different operating modes:- 31I2S has several different operating modes:-
@@ -41,12 +41,12 @@ I2S has several different operating modes:-
41PCM 41PCM
42=== 42===
43 43
44PCM is another 4 wire interface, very similar to I2S, that can support a more 44PCM is another 4 wire interface, very similar to I2S, which can support a more
45flexible protocol. It has bit clock (BCLK) and sync (SYNC) lines that are used 45flexible protocol. It has bit clock (BCLK) and sync (SYNC) lines that are used
46to synchronise the link whilst the Tx and Rx lines are used to transmit and 46to synchronise the link whilst the Tx and Rx lines are used to transmit and
47receive the audio data. Bit clock usually varies depending on sample rate 47receive the audio data. Bit clock usually varies depending on sample rate
48whilst sync runs at the sample rate. PCM also supports Time Division 48whilst sync runs at the sample rate. PCM also supports Time Division
49Multiplexing (TDM) in that several devices can use the bus similtaniuosly (This 49Multiplexing (TDM) in that several devices can use the bus simultaneously (this
50is sometimes referred to as network mode). 50is sometimes referred to as network mode).
51 51
52Common PCM operating modes:- 52Common PCM operating modes:-
diff --git a/Documentation/sound/alsa/soc/clocking.txt b/Documentation/sound/alsa/soc/clocking.txt
index e93960d53a1e..14930887c25f 100644
--- a/Documentation/sound/alsa/soc/clocking.txt
+++ b/Documentation/sound/alsa/soc/clocking.txt
@@ -2,20 +2,20 @@ Audio Clocking
2============== 2==============
3 3
4This text describes the audio clocking terms in ASoC and digital audio in 4This text describes the audio clocking terms in ASoC and digital audio in
5general. Note: Audio clocking can be complex ! 5general. Note: Audio clocking can be complex!
6 6
7 7
8Master Clock 8Master Clock
9------------ 9------------
10 10
11Every audio subsystem is driven by a master clock (sometimes refered to as MCLK 11Every audio subsystem is driven by a master clock (sometimes referred to as MCLK
12or SYSCLK). This audio master clock can be derived from a number of sources 12or SYSCLK). This audio master clock can be derived from a number of sources
13(e.g. crystal, PLL, CPU clock) and is responsible for producing the correct 13(e.g. crystal, PLL, CPU clock) and is responsible for producing the correct
14audio playback and capture sample rates. 14audio playback and capture sample rates.
15 15
16Some master clocks (e.g. PLL's and CPU based clocks) are configuarble in that 16Some master clocks (e.g. PLL's and CPU based clocks) are configurable in that
17their speed can be altered by software (depending on the system use and to save 17their speed can be altered by software (depending on the system use and to save
18power). Other master clocks are fixed at at set frequency (i.e. crystals). 18power). Other master clocks are fixed at a set frequency (i.e. crystals).
19 19
20 20
21DAI Clocks 21DAI Clocks
@@ -44,7 +44,7 @@ This relationship depends on the codec or SoC CPU in particular. In general
44it's best to configure BCLK to the lowest possible speed (depending on your 44it's best to configure BCLK to the lowest possible speed (depending on your
45rate, number of channels and wordsize) to save on power. 45rate, number of channels and wordsize) to save on power.
46 46
47It's also desireable to use the codec (if possible) to drive (or master) the 47It's also desirable to use the codec (if possible) to drive (or master) the
48audio clocks as it's usually gives more accurate sample rates than the CPU. 48audio clocks as it's usually gives more accurate sample rates than the CPU.
49 49
50 50
diff --git a/Documentation/sound/alsa/soc/codec.txt b/Documentation/sound/alsa/soc/codec.txt
index 48983c75aad9..1e766ad0ebd1 100644
--- a/Documentation/sound/alsa/soc/codec.txt
+++ b/Documentation/sound/alsa/soc/codec.txt
@@ -19,7 +19,7 @@ Optionally, codec drivers can also provide:-
19 6) DAPM event handler. 19 6) DAPM event handler.
20 7) DAC Digital mute control. 20 7) DAC Digital mute control.
21 21
22It's probably best to use this guide in conjuction with the existing codec 22It's probably best to use this guide in conjunction with the existing codec
23driver code in sound/soc/codecs/ 23driver code in sound/soc/codecs/
24 24
25ASoC Codec driver breakdown 25ASoC Codec driver breakdown
@@ -28,7 +28,7 @@ ASoC Codec driver breakdown
281 - Codec DAI and PCM configuration 281 - Codec DAI and PCM configuration
29----------------------------------- 29-----------------------------------
30Each codec driver must have a struct snd_soc_codec_dai to define it's DAI and 30Each codec driver must have a struct snd_soc_codec_dai to define it's DAI and
31PCM's capablities and operations. This struct is exported so that it can be 31PCM's capabilities and operations. This struct is exported so that it can be
32registered with the core by your machine driver. 32registered with the core by your machine driver.
33 33
34e.g. 34e.g.
@@ -67,7 +67,7 @@ EXPORT_SYMBOL_GPL(wm8731_dai);
67 67
682 - Codec control IO 682 - Codec control IO
69-------------------- 69--------------------
70The codec can ususally be controlled via an I2C or SPI style interface (AC97 70The codec can usually be controlled via an I2C or SPI style interface (AC97
71combines control with data in the DAI). The codec drivers will have to provide 71combines control with data in the DAI). The codec drivers will have to provide
72functions to read and write the codec registers along with supplying a register 72functions to read and write the codec registers along with supplying a register
73cache:- 73cache:-
diff --git a/Documentation/sound/alsa/soc/dapm.txt b/Documentation/sound/alsa/soc/dapm.txt
index c11877f5b4a1..ab0766fd7869 100644
--- a/Documentation/sound/alsa/soc/dapm.txt
+++ b/Documentation/sound/alsa/soc/dapm.txt
@@ -11,7 +11,7 @@ other PM systems.
11 11
12DAPM is also completely transparent to all user space applications as all power 12DAPM is also completely transparent to all user space applications as all power
13switching is done within the ASoC core. No code changes or recompiling are 13switching is done within the ASoC core. No code changes or recompiling are
14required for user space applications. DAPM makes power switching descisions based 14required for user space applications. DAPM makes power switching decisions based
15upon any audio stream (capture/playback) activity and audio mixer settings 15upon any audio stream (capture/playback) activity and audio mixer settings
16within the device. 16within the device.
17 17
@@ -38,7 +38,7 @@ There are 4 power domains within DAPM
38 Enabled and disabled when stream playback/capture is started and 38 Enabled and disabled when stream playback/capture is started and
39 stopped respectively. e.g. aplay, arecord. 39 stopped respectively. e.g. aplay, arecord.
40 40
41All DAPM power switching descisons are made automatically by consulting an audio 41All DAPM power switching decisions are made automatically by consulting an audio
42routing map of the whole machine. This map is specific to each machine and 42routing map of the whole machine. This map is specific to each machine and
43consists of the interconnections between every audio component (including 43consists of the interconnections between every audio component (including
44internal codec components). All audio components that effect power are called 44internal codec components). All audio components that effect power are called
diff --git a/Documentation/sound/alsa/soc/overview.txt b/Documentation/sound/alsa/soc/overview.txt
index 753c5cc5984a..c47ce9530677 100644
--- a/Documentation/sound/alsa/soc/overview.txt
+++ b/Documentation/sound/alsa/soc/overview.txt
@@ -2,18 +2,19 @@ ALSA SoC Layer
2============== 2==============
3 3
4The overall project goal of the ALSA System on Chip (ASoC) layer is to provide 4The overall project goal of the ALSA System on Chip (ASoC) layer is to provide
5better ALSA support for embedded system on chip procesors (e.g. pxa2xx, au1x00, 5better ALSA support for embedded system-on-chip processors (e.g. pxa2xx, au1x00,
6iMX, etc) and portable audio codecs. Currently there is some support in the 6iMX, etc) and portable audio codecs. Currently there is some support in the
7kernel for SoC audio, however it has some limitations:- 7kernel for SoC audio, however it has some limitations:-
8 8
9 * Currently, codec drivers are often tightly coupled to the underlying SoC 9 * Currently, codec drivers are often tightly coupled to the underlying SoC
10 cpu. This is not ideal and leads to code duplication i.e. Linux now has 4 10 CPU. This is not ideal and leads to code duplication i.e. Linux now has 4
11 different wm8731 drivers for 4 different SoC platforms. 11 different wm8731 drivers for 4 different SoC platforms.
12 12
13 * There is no standard method to signal user initiated audio events. 13 * There is no standard method to signal user initiated audio events (e.g.
14 e.g. Headphone/Mic insertion, Headphone/Mic detection after an insertion 14 Headphone/Mic insertion, Headphone/Mic detection after an insertion
15 event. These are quite common events on portable devices and ofter require 15 event). These are quite common events on portable devices and often require
16 machine specific code to re route audio, enable amps etc after such an event. 16 machine specific code to re-route audio, enable amps, etc., after such an
17 event.
17 18
18 * Current drivers tend to power up the entire codec when playing 19 * Current drivers tend to power up the entire codec when playing
19 (or recording) audio. This is fine for a PC, but tends to waste a lot of 20 (or recording) audio. This is fine for a PC, but tends to waste a lot of
@@ -44,7 +45,7 @@ features :-
44 signals the codec when to change power states. 45 signals the codec when to change power states.
45 46
46 * Machine specific controls: Allow machines to add controls to the sound card 47 * Machine specific controls: Allow machines to add controls to the sound card
47 e.g. volume control for speaker amp. 48 (e.g. volume control for speaker amp).
48 49
49To achieve all this, ASoC basically splits an embedded audio system into 3 50To achieve all this, ASoC basically splits an embedded audio system into 3
50components :- 51components :-
@@ -57,7 +58,7 @@ components :-
57 interface drivers (e.g. I2S, AC97, PCM) for that platform. 58 interface drivers (e.g. I2S, AC97, PCM) for that platform.
58 59
59 * Machine driver: The machine driver handles any machine specific controls and 60 * Machine driver: The machine driver handles any machine specific controls and
60 audio events. i.e. turing on an amp at start of playback. 61 audio events (e.g. turning on an amp at start of playback).
61 62
62 63
63Documentation 64Documentation
diff --git a/Documentation/sound/alsa/soc/platform.txt b/Documentation/sound/alsa/soc/platform.txt
index e95b16d5a53b..d4678b4dc6c6 100644
--- a/Documentation/sound/alsa/soc/platform.txt
+++ b/Documentation/sound/alsa/soc/platform.txt
@@ -20,7 +20,7 @@ struct snd_soc_ops {
20 int (*trigger)(struct snd_pcm_substream *, int); 20 int (*trigger)(struct snd_pcm_substream *, int);
21}; 21};
22 22
23The platform driver exports it's DMA functionailty via struct snd_soc_platform:- 23The platform driver exports its DMA functionality via struct snd_soc_platform:-
24 24
25struct snd_soc_platform { 25struct snd_soc_platform {
26 char *name; 26 char *name;
diff --git a/Documentation/sound/alsa/soc/pops_clicks.txt b/Documentation/sound/alsa/soc/pops_clicks.txt
index 2cf7ee5b3d74..3371bd9d7cfa 100644
--- a/Documentation/sound/alsa/soc/pops_clicks.txt
+++ b/Documentation/sound/alsa/soc/pops_clicks.txt
@@ -2,7 +2,7 @@ Audio Pops and Clicks
2===================== 2=====================
3 3
4Pops and clicks are unwanted audio artifacts caused by the powering up and down 4Pops and clicks are unwanted audio artifacts caused by the powering up and down
5of components within the audio subsystem. This is noticable on PC's when an 5of components within the audio subsystem. This is noticeable on PCs when an
6audio module is either loaded or unloaded (at module load time the sound card is 6audio module is either loaded or unloaded (at module load time the sound card is
7powered up and causes a popping noise on the speakers). 7powered up and causes a popping noise on the speakers).
8 8
@@ -16,7 +16,7 @@ Minimising Playback Pops and Clicks
16=================================== 16===================================
17 17
18Playback pops in portable audio subsystems cannot be completely eliminated atm, 18Playback pops in portable audio subsystems cannot be completely eliminated atm,
19however future audio codec hardware will have better pop and click supression. 19however future audio codec hardware will have better pop and click suppression.
20Pops can be reduced within playback by powering the audio components in a 20Pops can be reduced within playback by powering the audio components in a
21specific order. This order is different for startup and shutdown and follows 21specific order. This order is different for startup and shutdown and follows
22some basic rules:- 22some basic rules:-
@@ -33,7 +33,7 @@ Minimising Capture Pops and Clicks
33================================== 33==================================
34 34
35Capture artifacts are somewhat easier to get rid as we can delay activating the 35Capture artifacts are somewhat easier to get rid as we can delay activating the
36ADC until all the pops have occured. This follows similar power rules to 36ADC until all the pops have occurred. This follows similar power rules to
37playback in that components are powered in a sequence depending upon stream 37playback in that components are powered in a sequence depending upon stream
38startup or shutdown. 38startup or shutdown.
39 39