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authorStephen Rothwell <sfr@canb.auug.org.au>2010-05-04 12:52:50 +1000
committerStephen Rothwell <sfr@canb.auug.org.au>2010-05-04 12:52:50 +1000
commitac2d86d3055fb6557948a194761421935cd9210b (patch)
tree0879e4924537be5cf81de73651d1ca52ac0dbc44 /Documentation
parent9fe5aa1c1c881a0a81b3c6067c4ea944e4014145 (diff)
parent30031eb82c379eef4e2ef9b191b35dc0f53d1d43 (diff)
Merge remote branch 'sound/for-next'
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/DocBook/writing-an-alsa-driver.tmpl27
-rw-r--r--Documentation/sound/alsa/ALSA-Configuration.txt10
-rw-r--r--Documentation/sound/alsa/HD-Audio.txt4
3 files changed, 30 insertions, 11 deletions
diff --git a/Documentation/DocBook/writing-an-alsa-driver.tmpl b/Documentation/DocBook/writing-an-alsa-driver.tmpl
index 0d0f7b4d4b1a..0ba149de2608 100644
--- a/Documentation/DocBook/writing-an-alsa-driver.tmpl
+++ b/Documentation/DocBook/writing-an-alsa-driver.tmpl
@@ -5518,34 +5518,41 @@ struct _snd_pcm_runtime {
]]>
</programlisting>
</informalexample>
+
+ For the raw data, <structfield>size</structfield> field must be
+ set properly. This specifies the maximum size of the proc file access.
</para>
<para>
- The callback is much more complicated than the text-file
- version. You need to use a low-level I/O functions such as
+ The read/write callbacks of raw mode are more direct than the text mode.
+ You need to use a low-level I/O functions such as
<function>copy_from/to_user()</function> to transfer the
data.
<informalexample>
<programlisting>
<![CDATA[
- static long my_file_io_read(struct snd_info_entry *entry,
+ static ssize_t my_file_io_read(struct snd_info_entry *entry,
void *file_private_data,
struct file *file,
char *buf,
- unsigned long count,
- unsigned long pos)
+ size_t count,
+ loff_t pos)
{
- long size = count;
- if (pos + size > local_max_size)
- size = local_max_size - pos;
- if (copy_to_user(buf, local_data + pos, size))
+ if (copy_to_user(buf, local_data + pos, count))
return -EFAULT;
- return size;
+ return count;
}
]]>
</programlisting>
</informalexample>
+
+ If the size of the info entry has been set up properly,
+ <structfield>count</structfield> and <structfield>pos</structfield> are
+ guaranteed to fit within 0 and the given size.
+ You don't have to check the range in the callbacks unless any
+ other condition is required.
+
</para>
</chapter>
diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt
index bfcbbf88c44d..dc681badca67 100644
--- a/Documentation/sound/alsa/ALSA-Configuration.txt
+++ b/Documentation/sound/alsa/ALSA-Configuration.txt
@@ -227,6 +227,16 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
The power-management is supported.
+ Module snd-asihpi
+ -----------------
+
+ Module for AudioScience ASI soundcards
+
+ enable_hpi_hwdep - enable HPI hwdep for AudioScience soundcard
+
+ This module supports multiple cards.
+ The driver requires the firmware loader support on kernel.
+
Module snd-atiixp
-----------------
diff --git a/Documentation/sound/alsa/HD-Audio.txt b/Documentation/sound/alsa/HD-Audio.txt
index 98d14cb8a85d..bdafdbd32561 100644
--- a/Documentation/sound/alsa/HD-Audio.txt
+++ b/Documentation/sound/alsa/HD-Audio.txt
@@ -204,7 +204,6 @@ generic parser regardless of the codec. Usually the codec-specific
parser is much better than the generic parser (as now). Thus this
option is more about the debugging purpose.
-
Speaker and Headphone Output
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
One of the most frequent (and obvious) bugs with HD-audio is the
@@ -600,6 +599,9 @@ probing, the proc file is available, so you can get the raw codec
information before modified by the driver. Of course, the driver
isn't usable with `probe_only=1`. But you can continue the
configuration via hwdep sysfs file if hda-reconfig option is enabled.
+Using `probe_only` mask 2 skips the reset of HDA codecs (use
+`probe_only=3` as module option). The hwdep interface can be used
+to determine the BIOS codec initialization.
hda-verb