[PATCH v3 3/3] platform/x86: x86-android-tablets: Add Yoga Book audio GPIOs

[Maurizio Casciano]

The Yoga Book YB1-X91F/L uses two GPIOs provided by the RT5677 codec
itself. GPIO2 enables the second speaker amplifier and GPIO4 enables the
headphone path, but ACPI does not map either signal.

Describe both controls with a software node attached to the codec
device. The same node identifies the RT5677 GPIO provider, allowing the
Yoga Book ASoC machine driver to request the controls by function name.
Reprobe the codec after adding the node so the provider is initialized
with the new fwnode before the machine driver requests the descriptors.
Attach and remove the node with the tablet description lifetime.

Suggested-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Link: https://lore.kernel.org/platform-driver-x86/apLZF6b3F39z6bUc@xxxxxxxxxx/
Assisted-by: Codex:gpt-5.6-sol [sparse]
Signed-off-by: Maurizio Casciano <mauriziocasciano7@xxxxxxxxx>
---
 .../platform/x86/x86-android-tablets/lenovo.c | 61 +++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/drivers/platform/x86/x86-android-tablets/lenovo.c b/drivers/platform/x86/x86-android-tablets/lenovo.c
index 88693b9a1b01..1b7a95f23306 100644
--- a/drivers/platform/x86/x86-android-tablets/lenovo.c
+++ b/drivers/platform/x86/x86-android-tablets/lenovo.c
@@ -138,9 +138,26 @@ static const struct software_node lenovo_yb1_x91_drv2604_1_node = {
 	.properties = lenovo_yb1_x91_drv2604_1_props,
 };
 
+static const struct software_node lenovo_yb1_x91_rt5677_node;
+
+static const struct property_entry lenovo_yb1_x91_rt5677_props[] = {
+	/* GPIO2 drives the second speaker amp; GPIO4 drives headphones. */
+	PROPERTY_ENTRY_GPIO("speaker-enable2-gpios",
+			    &lenovo_yb1_x91_rt5677_node, 2, GPIO_ACTIVE_HIGH),
+	PROPERTY_ENTRY_GPIO("headphone-enable-gpios",
+			    &lenovo_yb1_x91_rt5677_node, 4, GPIO_ACTIVE_HIGH),
+	{ }
+};
+
+static const struct software_node lenovo_yb1_x91_rt5677_node = {
+	.name = "rt5677",
+	.properties = lenovo_yb1_x91_rt5677_props,
+};
+
 static const struct software_node *lenovo_yb1_x91_swnodes[] = {
 	&lenovo_yb1_x91_drv2604_0_node,
 	&lenovo_yb1_x91_drv2604_1_node,
+	&lenovo_yb1_x91_rt5677_node,
 	NULL
 };
 
@@ -345,11 +362,53 @@ static const struct x86_i2c_client_info lenovo_yogabook_x91_i2c_clients[] __init
 	},
 };
 
+#define YB1_X91_RT5677_DEVICE "i2c-10EC5677:00"
 #define YB1_X91_DRV2604_0_DEVICE "i2c-DRV2604:00"
 #define YB1_X91_DRV2604_1_DEVICE "i2c-DRV2604:01"
 
+static struct device *lenovo_yb1_x91_rt5677_dev;
 static struct device *lenovo_yb1_x91_drv2604_devs[2];
 
+static void lenovo_yb1_x91_add_audio_props(struct device *dev)
+{
+	struct device *codec_dev;
+	int ret;
+
+	codec_dev = bus_find_device_by_name(&i2c_bus_type, NULL,
+					    YB1_X91_RT5677_DEVICE);
+	if (!codec_dev) {
+		dev_warn(dev, "cannot find %s, audio will be unavailable\n",
+			 YB1_X91_RT5677_DEVICE);
+		return;
+	}
+
+	ret = device_add_software_node(codec_dev, &lenovo_yb1_x91_rt5677_node);
+	if (ret) {
+		put_device(codec_dev);
+		dev_warn(dev, "failed to add properties to %s: %d\n",
+			 YB1_X91_RT5677_DEVICE, ret);
+		return;
+	}
+
+	/* Ensure the codec GPIO provider is initialized with the new fwnode. */
+	ret = device_reprobe(codec_dev);
+	if (ret)
+		dev_warn(dev, "failed to reprobe %s: %d\n",
+			 YB1_X91_RT5677_DEVICE, ret);
+
+	lenovo_yb1_x91_rt5677_dev = codec_dev;
+}
+
+static void lenovo_yb1_x91_remove_audio_props(void)
+{
+	if (!lenovo_yb1_x91_rt5677_dev)
+		return;
+
+	device_remove_software_node(lenovo_yb1_x91_rt5677_dev);
+	put_device(lenovo_yb1_x91_rt5677_dev);
+	lenovo_yb1_x91_rt5677_dev = NULL;
+}
+
 static void lenovo_yb1_x91_add_haptics_props(struct device *dev, int index,
 					     const char *name)
 {
@@ -392,6 +451,7 @@ static void lenovo_yb1_x91_remove_haptics_props(int index)
 
 static int __init lenovo_yb1_x91_init(struct device *dev)
 {
+	lenovo_yb1_x91_add_audio_props(dev);
 	lenovo_yb1_x91_add_haptics_props(dev, 0, YB1_X91_DRV2604_0_DEVICE);
 	lenovo_yb1_x91_add_haptics_props(dev, 1, YB1_X91_DRV2604_1_DEVICE);
 
@@ -402,6 +462,7 @@ static void lenovo_yb1_x91_exit(void)
 {
 	lenovo_yb1_x91_remove_haptics_props(1);
 	lenovo_yb1_x91_remove_haptics_props(0);
+	lenovo_yb1_x91_remove_audio_props();
 }
 
 const struct x86_dev_info lenovo_yogabook_x91_info __initconst = {
-- 
2.53.0