Re: [PATCH v3 3/3] ALSA: hda: add support for Huawei WMI micmute LED

From: Pavel Machek
Date: Fri Nov 23 2018 - 18:33:18 EST


Hi!

> > > > > > > You have general-purpose LED, yet you are treating it as "something
> > > > > > > special". That means ugly code (quoted above) and lack of flexibility.
> > > > > > >

> > I'd prefer this to be normal LED and "mic muted" to become normal
> > trigger.
>
> But how would you solve the existing problem?
>
> As already mentioned, you'll need to hook the LED trigger and the
> actual mixer value change. This is the biggest missing piece, and
> it's the very reason we have the exported symbol from the platform
> driver side.
>
> So, if you prefer in that way, please implement that for the existing
> driver (thinkpad_acpi and dell-laptop) at first. I'll be really happy
> to get rid of the present ugly solution! But it's been there just
> because it's not so trivial at all. FWIW, this must be all done
> inside the kernel; otherwise you'll hit a regression.

Ok, what about something like this?

Tested, and it did not work. I guess I hooked it up at the wrong place
in LED subsystem... or maybe thinkpad x60 is wrong machine to test on.

Anyway, it looks less ugly than current code in alsa. We should not
really be using mixer settings to turn LED on and off.

Plus, it works in similar way triggers and LEDs "usually" do, and has
all the flexibility.

Signed-off-by: Pavel Machek <pavel@xxxxxx>

commit e7d6d170f2f45ea7a42c9ebb31869f440382e3ad

leds: ledtrig-sound: provide indication of muted microphone

Signed-off-by: Pavel Machek <pavel@xxxxxx>

diff --git a/drivers/leds/trigger/Makefile b/drivers/leds/trigger/Makefile
index 9bcb64e..c5ea19e 100644
--- a/drivers/leds/trigger/Makefile
+++ b/drivers/leds/trigger/Makefile
@@ -14,3 +14,4 @@ obj-$(CONFIG_LEDS_TRIGGER_CAMERA) += ledtrig-camera.o
obj-$(CONFIG_LEDS_TRIGGER_PANIC) += ledtrig-panic.o
obj-$(CONFIG_LEDS_TRIGGER_NETDEV) += ledtrig-netdev.o
obj-$(CONFIG_LEDS_TRIGGER_PATTERN) += ledtrig-pattern.o
+obj-y += ledtrig-sound.o
diff --git a/drivers/leds/trigger/ledtrig-sound.c b/drivers/leds/trigger/ledtrig-sound.c
new file mode 100644
index 0000000..608df35
--- /dev/null
+++ b/drivers/leds/trigger/ledtrig-sound.c
@@ -0,0 +1,23 @@
+/* GPLv2+.
+ * Copyright 2018 Pavel Machek <pavel@xxxxxx>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+
+DEFINE_LED_TRIGGER(ledtrig_micmute);
+
+void ledtrig_mic_muted(bool muted)
+{
+ led_trigger_event(ledtrig_micmute, muted ? LED_FULL : LED_OFF);
+}
+EXPORT_SYMBOL(ledtrig_mic_muted);
+
+static int __init ledtrig_micmute_init(void)
+{
+ led_trigger_register_simple("mic-muted", &ledtrig_micmute);
+
+ return 0;
+}
+device_initcall(ledtrig_micmute_init);
diff --git a/include/linux/leds.h b/include/linux/leds.h
index e4a9a00..c30e1cb 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -494,6 +494,14 @@ static inline void ledtrig_cpu(enum cpu_led_event evt)
}
#endif

+#ifdef CONFIG_LEDS_TRIGGERS
+extern void ledtrig_mic_muted(bool m);
+#else
+static inline void ledtrig_mic_muted(bool m) {}
+#endif
+
+
+
#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
extern void led_classdev_notify_brightness_hw_changed(
struct led_classdev *led_cdev, enum led_brightness brightness);
diff --git a/sound/pci/hda/hda_generic.c b/sound/pci/hda/hda_generic.c
index 276150f..3ec1f61 100644
--- a/sound/pci/hda/hda_generic.c
+++ b/sound/pci/hda/hda_generic.c
@@ -29,6 +29,7 @@
#include <linux/string.h>
#include <linux/bitops.h>
#include <linux/module.h>
+#include <linux/leds.h>
#include <sound/core.h>
#include <sound/jack.h>
#include <sound/tlv.h>
@@ -3929,6 +3930,7 @@ static void call_micmute_led_update(struct hda_codec *codec)
val = !spec->micmute_led.capture;
break;
}
+ ledtrig_mic_muted(!spec->micmute_led.capture);

if (val == spec->micmute_led.led_value)
return;
diff --git a/sound/pci/hda/thinkpad_helper.c b/sound/pci/hda/thinkpad_helper.c
index 568575b..f1b2265 100644
--- a/sound/pci/hda/thinkpad_helper.c
+++ b/sound/pci/hda/thinkpad_helper.c
@@ -23,6 +23,8 @@ static void update_tpacpi_mute_led(void *private_data, int enabled)
if (old_vmaster_hook)
old_vmaster_hook(private_data, enabled);

+ printk("mute led... %d\n", !enabled);
+
if (led_set_func)
led_set_func(TPACPI_LED_MUTE, !enabled);
}


--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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