From 7bb97dfdcaca0963d59f986e0a88d5bcd0783552 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 10 Nov 2016 16:59:08 +0100 Subject: ALSA: doc: ReSTize Bt87x.txt Another simple conversion from a plain text file. Put to cards directory. Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/Bt87x.txt | 78 ---------------------------------- Documentation/sound/cards/bt87x.rst | 83 +++++++++++++++++++++++++++++++++++++ Documentation/sound/cards/index.rst | 1 + 3 files changed, 84 insertions(+), 78 deletions(-) delete mode 100644 Documentation/sound/alsa/Bt87x.txt create mode 100644 Documentation/sound/cards/bt87x.rst diff --git a/Documentation/sound/alsa/Bt87x.txt b/Documentation/sound/alsa/Bt87x.txt deleted file mode 100644 index f158cde8b065..000000000000 --- a/Documentation/sound/alsa/Bt87x.txt +++ /dev/null @@ -1,78 +0,0 @@ -Intro -===== - -You might have noticed that the bt878 grabber cards have actually -_two_ PCI functions: - -$ lspci -[ ... ] -00:0a.0 Multimedia video controller: Brooktree Corporation Bt878 (rev 02) -00:0a.1 Multimedia controller: Brooktree Corporation Bt878 (rev 02) -[ ... ] - -The first does video, it is backward compatible to the bt848. The second -does audio. snd-bt87x is a driver for the second function. It's a sound -driver which can be used for recording sound (and _only_ recording, no -playback). As most TV cards come with a short cable which can be plugged -into your sound card's line-in you probably don't need this driver if all -you want to do is just watching TV... - -Some cards do not bother to connect anything to the audio input pins of -the chip, and some other cards use the audio function to transport MPEG -video data, so it's quite possible that audio recording may not work -with your card. - - -Driver Status -============= - -The driver is now stable. However, it doesn't know about many TV cards, -and it refuses to load for cards it doesn't know. - -If the driver complains ("Unknown TV card found, the audio driver will -not load"), you can specify the load_all=1 option to force the driver to -try to use the audio capture function of your card. If the frequency of -recorded data is not right, try to specify the digital_rate option with -other values than the default 32000 (often it's 44100 or 64000). - -If you have an unknown card, please mail the ID and board name to -, regardless of whether audio capture works -or not, so that future versions of this driver know about your card. - - -Audio modes -=========== - -The chip knows two different modes (digital/analog). snd-bt87x -registers two PCM devices, one for each mode. They cannot be used at -the same time. - - -Digital audio mode -================== - -The first device (hw:X,0) gives you 16 bit stereo sound. The sample -rate depends on the external source which feeds the Bt87x with digital -sound via I2S interface. - - -Analog audio mode (A/D) -======================= - -The second device (hw:X,1) gives you 8 or 16 bit mono sound. Supported -sample rates are between 119466 and 448000 Hz (yes, these numbers are -that high). If you've set the CONFIG_SND_BT87X_OVERCLOCK option, the -maximum sample rate is 1792000 Hz, but audio data becomes unusable -beyond 896000 Hz on my card. - -The chip has three analog inputs. Consequently you'll get a mixer -device to control these. - - -Have fun, - - Clemens - - -Written by Clemens Ladisch -big parts copied from btaudio.txt by Gerd Knorr diff --git a/Documentation/sound/cards/bt87x.rst b/Documentation/sound/cards/bt87x.rst new file mode 100644 index 000000000000..912732d3ef9e --- /dev/null +++ b/Documentation/sound/cards/bt87x.rst @@ -0,0 +1,83 @@ +================= +ALSA BT87x Driver +================= + +Intro +===== + +You might have noticed that the bt878 grabber cards have actually +*two* PCI functions: +:: + + $ lspci + [ ... ] + 00:0a.0 Multimedia video controller: Brooktree Corporation Bt878 (rev 02) + 00:0a.1 Multimedia controller: Brooktree Corporation Bt878 (rev 02) + [ ... ] + +The first does video, it is backward compatible to the bt848. The second +does audio. snd-bt87x is a driver for the second function. It's a sound +driver which can be used for recording sound (and *only* recording, no +playback). As most TV cards come with a short cable which can be plugged +into your sound card's line-in you probably don't need this driver if all +you want to do is just watching TV... + +Some cards do not bother to connect anything to the audio input pins of +the chip, and some other cards use the audio function to transport MPEG +video data, so it's quite possible that audio recording may not work +with your card. + + +Driver Status +============= + +The driver is now stable. However, it doesn't know about many TV cards, +and it refuses to load for cards it doesn't know. + +If the driver complains ("Unknown TV card found, the audio driver will +not load"), you can specify the ``load_all=1`` option to force the driver to +try to use the audio capture function of your card. If the frequency of +recorded data is not right, try to specify the ``digital_rate`` option with +other values than the default 32000 (often it's 44100 or 64000). + +If you have an unknown card, please mail the ID and board name to +, regardless of whether audio capture works +or not, so that future versions of this driver know about your card. + + +Audio modes +=========== + +The chip knows two different modes (digital/analog). snd-bt87x +registers two PCM devices, one for each mode. They cannot be used at +the same time. + + +Digital audio mode +================== + +The first device (hw:X,0) gives you 16 bit stereo sound. The sample +rate depends on the external source which feeds the Bt87x with digital +sound via I2S interface. + + +Analog audio mode (A/D) +======================= + +The second device (hw:X,1) gives you 8 or 16 bit mono sound. Supported +sample rates are between 119466 and 448000 Hz (yes, these numbers are +that high). If you've set the CONFIG_SND_BT87X_OVERCLOCK option, the +maximum sample rate is 1792000 Hz, but audio data becomes unusable +beyond 896000 Hz on my card. + +The chip has three analog inputs. Consequently you'll get a mixer +device to control these. + + +Have fun, + + Clemens + + +Written by Clemens Ladisch +big parts copied from btaudio.txt by Gerd Knorr diff --git a/Documentation/sound/cards/index.rst b/Documentation/sound/cards/index.rst index 0006bc547bb8..157372faae06 100644 --- a/Documentation/sound/cards/index.rst +++ b/Documentation/sound/cards/index.rst @@ -12,3 +12,4 @@ Card-Specific Information via82xx-mixer audiophile-usb mixart + bt87x -- cgit v1.2.3