[PATCH 3/3] ALSA:hda: add support for Huawei WMI MicMute LED

[Ayman Bagabas <ayman.bagabas@gmail.com>]

Some of Huawei laptops come with a LED in the mic mute key. This patch
enables and disable this LED when the internal microphone status is
changed.

Signed-off-by: Ayman Bagabas <ayman.bagabas@gmail.com>
---
 include/linux/huawei_wmi.h        |  7 ++++
 sound/pci/hda/huawei_wmi_helper.c | 66 +++++++++++++++++++++++++++++++
 sound/pci/hda/patch_realtek.c     | 12 ++++++
 3 files changed, 85 insertions(+)
 create mode 100644 include/linux/huawei_wmi.h
 create mode 100644 sound/pci/hda/huawei_wmi_helper.c

diff --git a/include/linux/huawei_wmi.h b/include/linux/huawei_wmi.h
new file mode 100644
index 000000000000..69b656c5029b
--- /dev/null
+++ b/include/linux/huawei_wmi.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __HUAWEI_WMI_H__
+#define __HUAWEI_WMI_H__
+
+int huawei_wmi_micmute_led_set(bool on);
+
+#endif
diff --git a/sound/pci/hda/huawei_wmi_helper.c b/sound/pci/hda/huawei_wmi_helper.c
new file mode 100644
index 000000000000..57256f51fd88
--- /dev/null
+++ b/sound/pci/hda/huawei_wmi_helper.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Helper functions for Huawei WMI Mic Mute LED;
+ * to be included from codec driver
+ */
+
+#if IS_ENABLED(CONFIG_HUAWEI_LAPTOP)
+#include <linux/huawei_wmi.h>
+
+static int (*huawei_wmi_micmute_led_set_func)(bool);
+
+static void update_huawei_wmi_micmute_led(struct hda_codec *codec,
+					  struct snd_kcontrol *kcontrol,
+					  struct snd_ctl_elem_value *ucontrol)
+{
+	if (!ucontrol || !huawei_wmi_micmute_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? */
+		bool val = ucontrol->value.integer.value[0] || ucontrol->value.integer.value[1];
+		huawei_wmi_micmute_led_set_func(!val);
+	}
+}
+
+static void alc_fixup_huawei_wmi(struct hda_codec *codec,
+				   const struct hda_fixup *fix, int action)
+{
+	struct hda_gen_spec *spec = codec->spec;
+	bool removefunc = false;
+
+	codec_info(codec, "In alc_fixup_huawei_wmi\n");
+
+	if (action == HDA_FIXUP_ACT_PROBE) {
+		if (!huawei_wmi_micmute_led_set_func)
+			huawei_wmi_micmute_led_set_func = symbol_request(huawei_wmi_micmute_led_set);
+		if (!huawei_wmi_micmute_led_set_func) {
+			codec_warn(codec, "Failed to find huawei_wmi symbol huawei_wmi_micmute_led_set\n");
+			return;
+		}
+
+		removefunc = true;
+		if (huawei_wmi_micmute_led_set_func(false) >= 0) {
+			if (spec->num_adc_nids > 1 && !spec->dyn_adc_switch)
+				codec_dbg(codec, "Skipping micmute LED control due to several ADCs");
+			else {
+				spec->cap_sync_hook = update_huawei_wmi_micmute_led;
+				removefunc = false;
+			}
+		}
+		codec_info(codec, "In alc_fixup_huawei_wmi IF\n");
+
+	}
+
+	if (huawei_wmi_micmute_led_set_func && (action == HDA_FIXUP_ACT_FREE || removefunc)) {
+		symbol_put(huawei_wmi_micmute_led_set);
+		huawei_wmi_micmute_led_set_func = NULL;
+	}
+}
+
+#else
+
+static void hda_fixup_huawei_wmi(struct hda_codec *codec,
+				   const struct hda_fixup *fix, int action)
+{
+}
+
+#endif
diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index 4f7a39c7883c..0dab00c0df50 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -5371,6 +5371,9 @@ static void alc_fixup_thinkpad_acpi(struct hda_codec *codec,
 /* for dell wmi mic mute led */
 #include "dell_wmi_helper.c"
 
+/* for huawei wmi mic mute led */
+#include "huawei_wmi_helper.c"
+
 /* for alc295_fixup_hp_top_speakers */
 #include "hp_x360_helper.c"
 
@@ -5494,6 +5497,7 @@ enum {
 	ALC255_FIXUP_DUMMY_LINEOUT_VERB,
 	ALC255_FIXUP_DELL_HEADSET_MIC,
 	ALC256_FIXUP_HUAWEI_MBXP_PINS,
+	ALC256_FIXUP_HUAWEI_WMI_MICMUTE_LED,
 	ALC295_FIXUP_HP_X360,
 	ALC221_FIXUP_HP_HEADSET_MIC,
 };
@@ -6348,6 +6352,10 @@ static const struct hda_fixup alc269_fixups[] = {
 		.chained = true,
 		.chain_id = ALC269_FIXUP_HEADSET_MIC
 	},
+	[ALC256_FIXUP_HUAWEI_WMI_MICMUTE_LED] = {
+		.type = HDA_FIXUP_FUNC,
+		.v.func = alc_fixup_huawei_wmi,
+	},
 	[ALC256_FIXUP_HUAWEI_MBXP_PINS] = {
 		.type = HDA_FIXUP_PINS,
 		.v.pins = (const struct hda_pintbl[]) {
@@ -6363,6 +6371,8 @@ static const struct hda_fixup alc269_fixups[] = {
 			{0x21, 0x04211020},
 			{ },
 		},
+		.chained = true,
+		.chain_id = ALC256_FIXUP_HUAWEI_WMI_MICMUTE_LED
 	},
 	[ALC295_FIXUP_HP_X360] = {
 		.type = HDA_FIXUP_FUNC,
@@ -6610,6 +6620,7 @@ static const struct snd_pci_quirk alc269_fixup_tbl[] = {
 	SND_PCI_QUIRK(0x17aa, 0x511e, "Thinkpad", ALC298_FIXUP_TPT470_DOCK),
 	SND_PCI_QUIRK(0x17aa, 0x511f, "Thinkpad", ALC298_FIXUP_TPT470_DOCK),
 	SND_PCI_QUIRK(0x19e5, 0x3204, "Huawei MBXP", ALC256_FIXUP_HUAWEI_MBXP_PINS),
+	SND_PCI_QUIRK(0x19e5, 0x3204, "Huawei MBXP", ALC256_FIXUP_HUAWEI_WMI_MICMUTE_LED),
 	SND_PCI_QUIRK(0x17aa, 0x3bf8, "Quanta FL1", ALC269_FIXUP_PCM_44K),
 	SND_PCI_QUIRK(0x17aa, 0x9e54, "LENOVO NB", ALC269_FIXUP_LENOVO_EAPD),
 	SND_PCI_QUIRK(0x1b7d, 0xa831, "Ordissimo EVE2 ", ALC269VB_FIXUP_ORDISSIMO_EVE2), /* Also known as Malata PC-B1303 */
@@ -6775,6 +6786,7 @@ static const struct hda_model_fixup alc269_fixup_models[] = {
 	{.id = ALC274_FIXUP_DELL_AIO_LINEOUT_VERB, .name = "alc274-dell-aio"},
 	{.id = ALC255_FIXUP_DUMMY_LINEOUT_VERB, .name = "alc255-dummy-lineout"},
 	{.id = ALC255_FIXUP_DELL_HEADSET_MIC, .name = "alc255-dell-headset"},
+	{.id = ALC256_FIXUP_HUAWEI_WMI_MICMUTE_LED, .name = "alc256-huawei-micmute"},
 	{.id = ALC295_FIXUP_HP_X360, .name = "alc295-hp-x360"},
 	{}
 };
-- 
2.17.2