summaryrefslogtreecommitdiff
path: root/Documentation/DocBook/writing-an-alsa-driver.tmpl
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2011-10-28 14:25:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-10-28 14:25:01 -0700
commit68d99b2c8efcb6ed3807a55569300c53b5f88be5 (patch)
treef189c8f2132d3668a2f0e503f5c3f8695b26a1c8 /Documentation/DocBook/writing-an-alsa-driver.tmpl
parent0e59e7e7feb5a12938fbf9135147eeda3238c6c4 (diff)
parent8128c9f21509f9a8b6da94ac432d845dda458406 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (549 commits) ALSA: hda - Fix ADC input-amp handling for Cx20549 codec ALSA: hda - Keep EAPD turned on for old Conexant chips ALSA: hda/realtek - Fix missing volume controls with ALC260 ASoC: wm8940: Properly set codec->dapm.bias_level ALSA: hda - Fix pin-config for ASUS W90V ALSA: hda - Fix surround/CLFE headphone and speaker pins order ALSA: hda - Fix typo ALSA: Update the sound git tree URL ALSA: HDA: Add new revision for ALC662 ASoC: max98095: Convert codec->hw_write to snd_soc_write ASoC: keep pointer to resource so it can be freed ASoC: sgtl5000: Fix wrong mask in some snd_soc_update_bits calls ASoC: wm8996: Fix wrong mask for setting WM8996_AIF_CLOCKING_2 ASoC: da7210: Add support for line out and DAC ASoC: da7210: Add support for DAPM ALSA: hda/realtek - Fix DAC assignments of multiple speakers ASoC: Use SGTL5000_LINREG_VDDD_MASK instead of hardcoded mask value ASoC: Set sgtl5000->ldo in ldo_regulator_register ASoC: wm8996: Use SND_SOC_DAPM_AIF_OUT for AIF2 Capture ASoC: wm8994: Use SND_SOC_DAPM_AIF_OUT for AIF3 Capture ...
Diffstat (limited to 'Documentation/DocBook/writing-an-alsa-driver.tmpl')
-rw-r--r--Documentation/DocBook/writing-an-alsa-driver.tmpl36
1 files changed, 21 insertions, 15 deletions
diff --git a/Documentation/DocBook/writing-an-alsa-driver.tmpl b/Documentation/DocBook/writing-an-alsa-driver.tmpl
index 598c22f3b3ac..5de23c007078 100644
--- a/Documentation/DocBook/writing-an-alsa-driver.tmpl
+++ b/Documentation/DocBook/writing-an-alsa-driver.tmpl
@@ -4288,7 +4288,7 @@ struct _snd_pcm_runtime {
<![CDATA[
struct snd_rawmidi *rmidi;
snd_mpu401_uart_new(card, 0, MPU401_HW_MPU401, port, info_flags,
- irq, irq_flags, &rmidi);
+ irq, &rmidi);
]]>
</programlisting>
</informalexample>
@@ -4343,6 +4343,13 @@ struct _snd_pcm_runtime {
by itself to start processing the output stream in the irq handler.
</para>
+ <para>
+ If the MPU-401 interface shares its interrupt with the other logical
+ devices on the card, set <constant>MPU401_INFO_IRQ_HOOK</constant>
+ (see <link linkend="midi-interface-interrupt-handler"><citetitle>
+ below</citetitle></link>).
+ </para>
+
<para>
Usually, the port address corresponds to the command port and
port + 1 corresponds to the data port. If not, you may change
@@ -4375,14 +4382,12 @@ struct _snd_pcm_runtime {
</para>
<para>
- The 6th argument specifies the irq number for UART. If the irq
- is already allocated, pass 0 to the 7th argument
- (<parameter>irq_flags</parameter>). Otherwise, pass the flags
- for irq allocation
- (<constant>SA_XXX</constant> bits) to it, and the irq will be
- reserved by the mpu401-uart layer. If the card doesn't generate
- UART interrupts, pass -1 as the irq number. Then a timer
- interrupt will be invoked for polling.
+ The 6th argument specifies the ISA irq number that will be
+ allocated. If no interrupt is to be allocated (because your
+ code is already allocating a shared interrupt, or because the
+ device does not use interrupts), pass -1 instead.
+ For a MPU-401 device without an interrupt, a polling timer
+ will be used instead.
</para>
</section>
@@ -4390,12 +4395,13 @@ struct _snd_pcm_runtime {
<title>Interrupt Handler</title>
<para>
When the interrupt is allocated in
- <function>snd_mpu401_uart_new()</function>, the private
- interrupt handler is used, hence you don't have anything else to do
- than creating the mpu401 stuff. Otherwise, you have to call
- <function>snd_mpu401_uart_interrupt()</function> explicitly when
- a UART interrupt is invoked and checked in your own interrupt
- handler.
+ <function>snd_mpu401_uart_new()</function>, an exclusive ISA
+ interrupt handler is automatically used, hence you don't have
+ anything else to do than creating the mpu401 stuff. Otherwise, you
+ have to set <constant>MPU401_INFO_IRQ_HOOK</constant>, and call
+ <function>snd_mpu401_uart_interrupt()</function> explicitly from your
+ own interrupt handler when it has determined that a UART interrupt
+ has occurred.
</para>
<para>