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-rw-r--r--Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl50
1 files changed, 27 insertions, 23 deletions
diff --git a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
index 1faf76383ba..635cbb94357 100644
--- a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
+++ b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
@@ -4215,7 +4215,7 @@ struct _snd_pcm_runtime {
<programlisting>
<![CDATA[
struct snd_rawmidi *rmidi;
- snd_mpu401_uart_new(card, 0, MPU401_HW_MPU401, port, integrated,
+ snd_mpu401_uart_new(card, 0, MPU401_HW_MPU401, port, info_flags,
irq, irq_flags, &rmidi);
]]>
</programlisting>
@@ -4242,15 +4242,36 @@ struct _snd_pcm_runtime {
</para>
<para>
+ The 5th argument is bitflags for additional information.
When the i/o port address above is a part of the PCI i/o
region, the MPU401 i/o port might have been already allocated
- (reserved) by the driver itself. In such a case, pass non-zero
- to the 5th argument
- (<parameter>integrated</parameter>). Otherwise, pass 0 to it,
+ (reserved) by the driver itself. In such a case, pass a bit flag
+ <constant>MPU401_INFO_INTEGRATED</constant>,
and
the mpu401-uart layer will allocate the i/o ports by itself.
</para>
+ <para>
+ When the controller supports only the input or output MIDI stream,
+ pass <constant>MPU401_INFO_INPUT</constant> or
+ <constant>MPU401_INFO_OUTPUT</constant> bitflag, respectively.
+ Then the rawmidi instance is created as a single stream.
+ </para>
+
+ <para>
+ <constant>MPU401_INFO_MMIO</constant> bitflag is used to change
+ the access method to MMIO (via readb and writeb) instead of
+ iob and outb. In this case, you have to pass the iomapped address
+ to <function>snd_mpu401_uart_new()</function>.
+ </para>
+
+ <para>
+ When <constant>MPU401_INFO_TX_IRQ</constant> is set, the output
+ stream isn't checked in the default interrupt handler. The driver
+ needs to call <function>snd_mpu401_uart_interrupt_tx()</function>
+ by itself to start processing the output stream in irq handler.
+ </para>
+
<para>
Usually, the port address corresponds to the command port and
port + 1 corresponds to the data port. If not, you may change
@@ -5333,7 +5354,7 @@ struct _snd_pcm_runtime {
<informalexample>
<programlisting>
<![CDATA[
- snd_info_set_text_ops(entry, chip, read_size, my_proc_read);
+ snd_info_set_text_ops(entry, chip, my_proc_read);
]]>
</programlisting>
</informalexample>
@@ -5394,7 +5415,6 @@ struct _snd_pcm_runtime {
<informalexample>
<programlisting>
<![CDATA[
- entry->c.text.write_size = 256;
entry->c.text.write = my_proc_write;
]]>
</programlisting>
@@ -5402,22 +5422,6 @@ struct _snd_pcm_runtime {
</para>
<para>
- The buffer size for read is set to 1024 implicitly by
- <function>snd_info_set_text_ops()</function>. It should suffice
- in most cases (the size will be aligned to
- <constant>PAGE_SIZE</constant> anyway), but if you need to handle
- very large text files, you can set it explicitly, too.
-
- <informalexample>
- <programlisting>
-<![CDATA[
- entry->c.text.read_size = 65536;
-]]>
- </programlisting>
- </informalexample>
- </para>
-
- <para>
For the write callback, you can use
<function>snd_info_get_line()</function> to get a text line, and
<function>snd_info_get_str()</function> to retrieve a string from
@@ -5562,7 +5566,7 @@ struct _snd_pcm_runtime {
power status.</para></listitem>
<listitem><para>Call <function>snd_pcm_suspend_all()</function> to suspend the running PCM streams.</para></listitem>
<listitem><para>If AC97 codecs are used, call
- <function>snd_ac97_resume()</function> for each codec.</para></listitem>
+ <function>snd_ac97_suspend()</function> for each codec.</para></listitem>
<listitem><para>Save the register values if necessary.</para></listitem>
<listitem><para>Stop the hardware if necessary.</para></listitem>
<listitem><para>Disable the PCI device by calling