ALSA: hda - add mic mute led hook for dell machines

The mic mute led on dell laptops is controlled by the wmi driver.
Followed this part being merged to the kernel, we add the mic mute led
hook in the hda driver.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 76 insertions, 0 deletions

diff --git a/sound/pci/hda/dell_wmi_helper.c b/sound/pci/hda/dell_wmi_helper.c
new file mode 100644
index 000000000000..9c22f95838ef
--- /dev/null
+++ b/sound/pci/hda/dell_wmi_helper.c
@@ -0,0 +1,76 @@
+/* Helper functions for Dell Mic Mute LED control;
+ * to be included from codec driver
+ */
+
+#if IS_ENABLED(CONFIG_LEDS_DELL_NETBOOKS)
+#include <linux/dell-led.h>
+
+static int dell_led_value;
+static int (*dell_led_set_func)(int, int);
+static void (*dell_old_cap_hook)(struct hda_codec *,
+			         struct snd_kcontrol *,
+				 struct snd_ctl_elem_value *);
+
+static void update_dell_wmi_micmute_led(struct hda_codec *codec,
+				        struct snd_kcontrol *kcontrol,
+					struct snd_ctl_elem_value *ucontrol)
+{
+	if (dell_old_cap_hook)
+		dell_old_cap_hook(codec, kcontrol, ucontrol);
+
+	if (!ucontrol || !dell_led_set_func)
+		return;
+	if (strcmp("Capture Switch", ucontrol->id.name) == 0 && ucontrol->id.index == 0) {
+		/* TODO: How do I verify if it's a mono or stereo here? */
+		int val = (ucontrol->value.integer.value[0] || ucontrol->value.integer.value[1]) ? 0 : 1;
+		if (val == dell_led_value)
+			return;
+		dell_led_value = val;
+		if (dell_led_set_func)
+			dell_led_set_func(DELL_LED_MICMUTE, dell_led_value);
+	}
+}
+
+
+static void alc_fixup_dell_wmi(struct hda_codec *codec,
+			       const struct hda_fixup *fix, int action)
+{
+	struct alc_spec *spec = codec->spec;
+	bool removefunc = false;
+
+	if (action == HDA_FIXUP_ACT_PROBE) {
+		if (!dell_led_set_func)
+			dell_led_set_func = symbol_request(dell_app_wmi_led_set);
+		if (!dell_led_set_func) {
+			codec_warn(codec, "Failed to find dell wmi symbol dell_app_wmi_led_set\n");
+			return;
+		}
+
+		removefunc = true;
+		if (dell_led_set_func(DELL_LED_MICMUTE, false) >= 0) {
+			dell_led_value = 0;
+			if (spec->gen.num_adc_nids > 1)
+				codec_dbg(codec, "Skipping micmute LED control due to several ADCs");
+			else {
+				dell_old_cap_hook = spec->gen.cap_sync_hook;
+				spec->gen.cap_sync_hook = update_dell_wmi_micmute_led;
+				removefunc = false;
+			}
+		}
+
+	}
+
+	if (dell_led_set_func && (action == HDA_FIXUP_ACT_FREE || removefunc)) {
+		symbol_put(dell_app_wmi_led_set);
+		dell_led_set_func = NULL;
+		dell_old_cap_hook = NULL;
+	}
+}
+
+#else /* CONFIG_LEDS_DELL_NETBOOKS */
+static void alc_fixup_dell_wmi(struct hda_codec *codec,
+			       const struct hda_fixup *fix, int action)
+{
+}
+
+#endif /* CONFIG_LEDS_DELL_NETBOOKS */