linux-kernel - [PATCH v2 11/12] ASoC: doc: dapm: update section "DAPM Widget Events"

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240426-dapm-docs-v2-11-87b07547eb5b@bootlin.com>
Date: Fri, 26 Apr 2024 18:56:44 +0200
From: Luca Ceresoli <luca.ceresoli@...tlin.com>
To: Liam Girdwood <lgirdwood@...il.com>, Mark Brown <broonie@...nel.org>, 
 Jaroslav Kysela <perex@...ex.cz>, Takashi Iwai <tiwai@...e.com>, 
 Jonathan Corbet <corbet@....net>
Cc: Alexandre Belloni <alexandre.belloni@...tlin.com>, 
 Bagas Sanjaya <bagasdotme@...il.com>, 
 Thomas Petazzoni <thomas.petazzoni@...tlin.com>, 
 linux-sound@...r.kernel.org, linux-doc@...r.kernel.org, 
 linux-kernel@...r.kernel.org, Luca Ceresoli <luca.ceresoli@...tlin.com>
Subject: [PATCH v2 11/12] ASoC: doc: dapm: update section "DAPM Widget
 Events"

The example in this section is not in the kernel sources anymore. Replace
it with an up to date code fragment. Reword the initial paragraph. Remove
"Please" which is not standard practice in documentation.

Reviewed-by: Alexandre Belloni <alexandre.belloni@...tlin.com>
Signed-off-by: Luca Ceresoli <luca.ceresoli@...tlin.com>
---
 Documentation/sound/soc/dapm.rst | 30 ++++++++++++++++++------------
 1 file changed, 18 insertions(+), 12 deletions(-)

diff --git a/Documentation/sound/soc/dapm.rst b/Documentation/sound/soc/dapm.rst
index 6096334226c0..da9313e10fd4 100644
--- a/Documentation/sound/soc/dapm.rst
+++ b/Documentation/sound/soc/dapm.rst
@@ -377,23 +377,29 @@ jacks can also be switched OFF.
 DAPM Widget Events
 ==================
 
-Some widgets can register their interest with the DAPM core in PM events.
-e.g. A Speaker with an amplifier registers a widget so the amplifier can be
-powered only when the spk is in use.
-::
+Widgets needing to implement a more complex behaviour than what DAPM can do
+can set a custom "event handler" by setting a function pointer. An example
+is a power supply needing to enable a GPIO::
 
-  /* turn speaker amplifier on/off depending on use */
-  static int corgi_amp_event(struct snd_soc_dapm_widget *w, int event)
+  static int sof_es8316_speaker_power_event(struct snd_soc_dapm_widget *w,
+  					  struct snd_kcontrol *kcontrol, int event)
   {
-	gpio_set_value(CORGI_GPIO_APM_ON, SND_SOC_DAPM_EVENT_ON(event));
-	return 0;
+  	if (SND_SOC_DAPM_EVENT_ON(event))
+  		gpiod_set_value_cansleep(gpio_pa, true);
+  	else
+  		gpiod_set_value_cansleep(gpio_pa, false);
+
+  	return 0;
   }
 
-  /* corgi machine dapm widgets */
-  static const struct snd_soc_dapm_widget wm8731_dapm_widgets =
-	SND_SOC_DAPM_SPK("Ext Spk", corgi_amp_event);
+  static const struct snd_soc_dapm_widget st_widgets[] = {
+  	...
+  	SND_SOC_DAPM_SUPPLY("Speaker Power", SND_SOC_NOPM, 0, 0,
+  			    sof_es8316_speaker_power_event,
+  			    SND_SOC_DAPM_PRE_PMD | SND_SOC_DAPM_POST_PMU),
+  };
 
-Please see soc-dapm.h for all other widgets that support events.
+See soc-dapm.h for all other widgets that support events.
 
 
 Event types

-- 
2.34.1