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-rw-r--r--Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl56
1 files changed, 15 insertions, 41 deletions
diff --git a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
index 24e85520890..260334c98d9 100644
--- a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
+++ b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
@@ -18,8 +18,8 @@
</affiliation>
</author>
- <date>March 6, 2005</date>
- <edition>0.3.4</edition>
+ <date>October 6, 2005</date>
+ <edition>0.3.5</edition>
<abstract>
<para>
@@ -30,7 +30,7 @@
<legalnotice>
<para>
- Copyright (c) 2002-2004 Takashi Iwai <email>tiwai@suse.de</email>
+ Copyright (c) 2002-2005 Takashi Iwai <email>tiwai@suse.de</email>
</para>
<para>
@@ -1433,25 +1433,10 @@
<informalexample>
<programlisting>
<![CDATA[
- if (chip->res_port) {
- release_resource(chip->res_port);
- kfree_nocheck(chip->res_port);
- }
+ release_and_free_resource(chip->res_port);
]]>
</programlisting>
</informalexample>
-
- As you can see, the resource pointer is also to be freed
- via <function>kfree_nocheck()</function> after
- <function>release_resource()</function> is called. You
- cannot use <function>kfree()</function> here, because on ALSA,
- <function>kfree()</function> may be a wrapper to its own
- allocator with the memory debugging. Since the resource pointer
- is allocated externally outside the ALSA, it must be released
- via the native
- <function>kfree()</function>.
- <function>kfree_nocheck()</function> is used for that; it calls
- the native <function>kfree()</function> without wrapper.
</para>
<para>
@@ -2190,8 +2175,7 @@ struct _snd_pcm_runtime {
unsigned int rate_den;
/* -- SW params -- */
- int tstamp_timespec; /* use timeval (0) or timespec (1) */
- snd_pcm_tstamp_t tstamp_mode; /* mmap timestamp is updated */
+ struct timespec tstamp_mode; /* mmap timestamp is updated */
unsigned int period_step;
unsigned int sleep_min; /* min ticks to sleep */
snd_pcm_uframes_t xfer_align; /* xfer size need to be a multiple */
@@ -3709,8 +3693,7 @@ struct _snd_pcm_runtime {
<para>
Here, the chip instance is retrieved via
<function>snd_kcontrol_chip()</function> macro. This macro
- converts from kcontrol-&gt;private_data to the type defined by
- <type>chip_t</type>. The
+ just accesses to kcontrol-&gt;private_data. The
kcontrol-&gt;private_data field is
given as the argument of <function>snd_ctl_new()</function>
(see the later subsection
@@ -5998,32 +5981,23 @@ struct _snd_pcm_runtime {
The first argument is the expression to evaluate, and the
second argument is the action if it fails. When
<constant>CONFIG_SND_DEBUG</constant>, is set, it will show an
- error message such as <computeroutput>BUG? (xxx) (called from
- yyy)</computeroutput>. When no debug flag is set, this is
- ignored.
+ error message such as <computeroutput>BUG? (xxx)</computeroutput>
+ together with stack trace.
</para>
- </section>
-
- <section id="useful-functions-snd-runtime-check">
- <title><function>snd_runtime_check()</function></title>
<para>
- This macro is quite similar with
- <function>snd_assert()</function>. Unlike
- <function>snd_assert()</function>, the expression is always
- evaluated regardless of
- <constant>CONFIG_SND_DEBUG</constant>. When
- <constant>CONFIG_SND_DEBUG</constant> is set, the macro will
- show a message like <computeroutput>ERROR (xx) (called from
- yyy)</computeroutput>.
+ When no debug flag is set, this macro is ignored.
</para>
</section>
<section id="useful-functions-snd-bug">
<title><function>snd_BUG()</function></title>
<para>
- It calls <function>snd_assert(0,)</function> -- that is, just
- prints the error message at the point. It's useful to show that
- a fatal error happens there.
+ It shows <computeroutput>BUG?</computeroutput> message and
+ stack trace as well as <function>snd_assert</function> at the point.
+ It's useful to show that a fatal error happens there.
+ </para>
+ <para>
+ When no debug flag is set, this macro is ignored.
</para>
</section>
</chapter>