diff options
author | Matt LaPlante <kernel1@cyberdogtech.com> | 2007-10-19 19:34:40 -0400 |
---|---|---|
committer | Adrian Bunk <bunk@kernel.org> | 2007-10-19 19:34:40 -0400 |
commit | 01dd2fbf0da4019c380b6ca22a074538fb31db5a (patch) | |
tree | 210291bd341c4450c8c51d8db890af0978f4035d /Documentation/sound/alsa/soc | |
parent | 0f035b8e8491f4ff87f6eec3e3f754d36b39d7a2 (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/soc')
-rw-r--r-- | Documentation/sound/alsa/soc/DAI.txt | 8 | ||||
-rw-r--r-- | Documentation/sound/alsa/soc/clocking.txt | 10 | ||||
-rw-r--r-- | Documentation/sound/alsa/soc/codec.txt | 6 | ||||
-rw-r--r-- | Documentation/sound/alsa/soc/dapm.txt | 4 | ||||
-rw-r--r-- | Documentation/sound/alsa/soc/overview.txt | 17 | ||||
-rw-r--r-- | Documentation/sound/alsa/soc/platform.txt | 2 | ||||
-rw-r--r-- | Documentation/sound/alsa/soc/pops_clicks.txt | 6 |
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 |
23 | Rx lines are used for audio transmision, whilst the bit clock (BCLK) and | 23 | Rx lines are used for audio transmission, whilst the bit clock (BCLK) and |
24 | left/right clock (LRC) synchronise the link. I2S is flexible in that either the | 24 | left/right clock (LRC) synchronise the link. I2S is flexible in that either the |
25 | controller or CODEC can drive (master) the BCLK and LRC clock lines. Bit clock | 25 | controller or CODEC can drive (master) the BCLK and LRC clock lines. Bit clock |
26 | usually varies depending on the sample rate and the master system clock | 26 | usually 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 |
28 | ADC and DAC LRCLK's, this allows for similtanious capture and playback at | 28 | ADC and DAC LRCLK's, this allows for simultaneous capture and playback at |
29 | different sample rates. | 29 | different sample rates. |
30 | 30 | ||
31 | I2S has several different operating modes:- | 31 | I2S has several different operating modes:- |
@@ -41,12 +41,12 @@ I2S has several different operating modes:- | |||
41 | PCM | 41 | PCM |
42 | === | 42 | === |
43 | 43 | ||
44 | PCM is another 4 wire interface, very similar to I2S, that can support a more | 44 | PCM is another 4 wire interface, very similar to I2S, which can support a more |
45 | flexible protocol. It has bit clock (BCLK) and sync (SYNC) lines that are used | 45 | flexible protocol. It has bit clock (BCLK) and sync (SYNC) lines that are used |
46 | to synchronise the link whilst the Tx and Rx lines are used to transmit and | 46 | to synchronise the link whilst the Tx and Rx lines are used to transmit and |
47 | receive the audio data. Bit clock usually varies depending on sample rate | 47 | receive the audio data. Bit clock usually varies depending on sample rate |
48 | whilst sync runs at the sample rate. PCM also supports Time Division | 48 | whilst sync runs at the sample rate. PCM also supports Time Division |
49 | Multiplexing (TDM) in that several devices can use the bus similtaniuosly (This | 49 | Multiplexing (TDM) in that several devices can use the bus simultaneously (this |
50 | is sometimes referred to as network mode). | 50 | is sometimes referred to as network mode). |
51 | 51 | ||
52 | Common PCM operating modes:- | 52 | Common 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 | ||
4 | This text describes the audio clocking terms in ASoC and digital audio in | 4 | This text describes the audio clocking terms in ASoC and digital audio in |
5 | general. Note: Audio clocking can be complex ! | 5 | general. Note: Audio clocking can be complex! |
6 | 6 | ||
7 | 7 | ||
8 | Master Clock | 8 | Master Clock |
9 | ------------ | 9 | ------------ |
10 | 10 | ||
11 | Every audio subsystem is driven by a master clock (sometimes refered to as MCLK | 11 | Every audio subsystem is driven by a master clock (sometimes referred to as MCLK |
12 | or SYSCLK). This audio master clock can be derived from a number of sources | 12 | or 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 |
14 | audio playback and capture sample rates. | 14 | audio playback and capture sample rates. |
15 | 15 | ||
16 | Some master clocks (e.g. PLL's and CPU based clocks) are configuarble in that | 16 | Some master clocks (e.g. PLL's and CPU based clocks) are configurable in that |
17 | their speed can be altered by software (depending on the system use and to save | 17 | their speed can be altered by software (depending on the system use and to save |
18 | power). Other master clocks are fixed at at set frequency (i.e. crystals). | 18 | power). Other master clocks are fixed at a set frequency (i.e. crystals). |
19 | 19 | ||
20 | 20 | ||
21 | DAI Clocks | 21 | DAI Clocks |
@@ -44,7 +44,7 @@ This relationship depends on the codec or SoC CPU in particular. In general | |||
44 | it's best to configure BCLK to the lowest possible speed (depending on your | 44 | it's best to configure BCLK to the lowest possible speed (depending on your |
45 | rate, number of channels and wordsize) to save on power. | 45 | rate, number of channels and wordsize) to save on power. |
46 | 46 | ||
47 | It's also desireable to use the codec (if possible) to drive (or master) the | 47 | It's also desirable to use the codec (if possible) to drive (or master) the |
48 | audio clocks as it's usually gives more accurate sample rates than the CPU. | 48 | audio 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 | ||
22 | It's probably best to use this guide in conjuction with the existing codec | 22 | It's probably best to use this guide in conjunction with the existing codec |
23 | driver code in sound/soc/codecs/ | 23 | driver code in sound/soc/codecs/ |
24 | 24 | ||
25 | ASoC Codec driver breakdown | 25 | ASoC Codec driver breakdown |
@@ -28,7 +28,7 @@ ASoC Codec driver breakdown | |||
28 | 1 - Codec DAI and PCM configuration | 28 | 1 - Codec DAI and PCM configuration |
29 | ----------------------------------- | 29 | ----------------------------------- |
30 | Each codec driver must have a struct snd_soc_codec_dai to define it's DAI and | 30 | Each codec driver must have a struct snd_soc_codec_dai to define it's DAI and |
31 | PCM's capablities and operations. This struct is exported so that it can be | 31 | PCM's capabilities and operations. This struct is exported so that it can be |
32 | registered with the core by your machine driver. | 32 | registered with the core by your machine driver. |
33 | 33 | ||
34 | e.g. | 34 | e.g. |
@@ -67,7 +67,7 @@ EXPORT_SYMBOL_GPL(wm8731_dai); | |||
67 | 67 | ||
68 | 2 - Codec control IO | 68 | 2 - Codec control IO |
69 | -------------------- | 69 | -------------------- |
70 | The codec can ususally be controlled via an I2C or SPI style interface (AC97 | 70 | The codec can usually be controlled via an I2C or SPI style interface (AC97 |
71 | combines control with data in the DAI). The codec drivers will have to provide | 71 | combines control with data in the DAI). The codec drivers will have to provide |
72 | functions to read and write the codec registers along with supplying a register | 72 | functions to read and write the codec registers along with supplying a register |
73 | cache:- | 73 | cache:- |
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 | ||
12 | DAPM is also completely transparent to all user space applications as all power | 12 | DAPM is also completely transparent to all user space applications as all power |
13 | switching is done within the ASoC core. No code changes or recompiling are | 13 | switching is done within the ASoC core. No code changes or recompiling are |
14 | required for user space applications. DAPM makes power switching descisions based | 14 | required for user space applications. DAPM makes power switching decisions based |
15 | upon any audio stream (capture/playback) activity and audio mixer settings | 15 | upon any audio stream (capture/playback) activity and audio mixer settings |
16 | within the device. | 16 | within 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 | ||
41 | All DAPM power switching descisons are made automatically by consulting an audio | 41 | All DAPM power switching decisions are made automatically by consulting an audio |
42 | routing map of the whole machine. This map is specific to each machine and | 42 | routing map of the whole machine. This map is specific to each machine and |
43 | consists of the interconnections between every audio component (including | 43 | consists of the interconnections between every audio component (including |
44 | internal codec components). All audio components that effect power are called | 44 | internal 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 | ||
4 | The overall project goal of the ALSA System on Chip (ASoC) layer is to provide | 4 | The overall project goal of the ALSA System on Chip (ASoC) layer is to provide |
5 | better ALSA support for embedded system on chip procesors (e.g. pxa2xx, au1x00, | 5 | better ALSA support for embedded system-on-chip processors (e.g. pxa2xx, au1x00, |
6 | iMX, etc) and portable audio codecs. Currently there is some support in the | 6 | iMX, etc) and portable audio codecs. Currently there is some support in the |
7 | kernel for SoC audio, however it has some limitations:- | 7 | kernel 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 | ||
49 | To achieve all this, ASoC basically splits an embedded audio system into 3 | 50 | To achieve all this, ASoC basically splits an embedded audio system into 3 |
50 | components :- | 51 | components :- |
@@ -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 | ||
63 | Documentation | 64 | Documentation |
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 | ||
23 | The platform driver exports it's DMA functionailty via struct snd_soc_platform:- | 23 | The platform driver exports its DMA functionality via struct snd_soc_platform:- |
24 | 24 | ||
25 | struct snd_soc_platform { | 25 | struct 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 | ||
4 | Pops and clicks are unwanted audio artifacts caused by the powering up and down | 4 | Pops and clicks are unwanted audio artifacts caused by the powering up and down |
5 | of components within the audio subsystem. This is noticable on PC's when an | 5 | of components within the audio subsystem. This is noticeable on PCs when an |
6 | audio module is either loaded or unloaded (at module load time the sound card is | 6 | audio module is either loaded or unloaded (at module load time the sound card is |
7 | powered up and causes a popping noise on the speakers). | 7 | powered up and causes a popping noise on the speakers). |
8 | 8 | ||
@@ -16,7 +16,7 @@ Minimising Playback Pops and Clicks | |||
16 | =================================== | 16 | =================================== |
17 | 17 | ||
18 | Playback pops in portable audio subsystems cannot be completely eliminated atm, | 18 | Playback pops in portable audio subsystems cannot be completely eliminated atm, |
19 | however future audio codec hardware will have better pop and click supression. | 19 | however future audio codec hardware will have better pop and click suppression. |
20 | Pops can be reduced within playback by powering the audio components in a | 20 | Pops can be reduced within playback by powering the audio components in a |
21 | specific order. This order is different for startup and shutdown and follows | 21 | specific order. This order is different for startup and shutdown and follows |
22 | some basic rules:- | 22 | some basic rules:- |
@@ -33,7 +33,7 @@ Minimising Capture Pops and Clicks | |||
33 | ================================== | 33 | ================================== |
34 | 34 | ||
35 | Capture artifacts are somewhat easier to get rid as we can delay activating the | 35 | Capture artifacts are somewhat easier to get rid as we can delay activating the |
36 | ADC until all the pops have occured. This follows similar power rules to | 36 | ADC until all the pops have occurred. This follows similar power rules to |
37 | playback in that components are powered in a sequence depending upon stream | 37 | playback in that components are powered in a sequence depending upon stream |
38 | startup or shutdown. | 38 | startup or shutdown. |
39 | 39 | ||