HID: amd_sfh: Add a new interface for exporting ALS data

AMDSFH has information about the Ambient light via the Ambient
Light Sensor (ALS) which is part of the AMD sensor fusion hub.

Add a new interface to export this information, where other drivers like
PMF can use this information to enhance user experiences.

Link: https://lore.kernel.org/all/ad064333-48a4-4cfa-9428-69e8a7c44667@redhat.com/
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Co-developed-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

drivers/hid/amd-sfh-hid/amd_sfh_common.h

@@ -39,6 +39,7 @@ struct amd_mp2_sensor_info {
 
 struct sfh_dev_status {
 	bool is_hpd_present;
+	bool is_als_present;
 };
 
 struct amd_mp2_dev {

drivers/hid/amd-sfh-hid/sfh1_1/amd_sfh_init.c

@@ -77,6 +77,9 @@ static int amd_sfh_hid_client_deinit(struct amd_mp2_dev *privdata)
 		case HPD_IDX:
 			privdata->dev_en.is_hpd_present = false;
 			break;
+		case ALS_IDX:
+			privdata->dev_en.is_als_present = false;
+			break;
 		}
 
 		if (cl_data->sensor_sts[i] == SENSOR_ENABLED) {
@@ -188,6 +191,9 @@ static int amd_sfh1_1_hid_client_init(struct amd_mp2_dev *privdata)
 			case HPD_IDX:
 				privdata->dev_en.is_hpd_present = true;
 				break;
+			case ALS_IDX:
+				privdata->dev_en.is_als_present = true;
+				break;
 			}
 		}
 		dev_dbg(dev, "sid 0x%x (%s) status 0x%x\n",

drivers/hid/amd-sfh-hid/sfh1_1/amd_sfh_interface.c

@@ -103,12 +103,34 @@ static int amd_sfh_hpd_info(u8 *user_present)
 	return 0;
 }
 
+static int amd_sfh_als_info(u32 *ambient_light)
+{
+	struct sfh_als_data als_data;
+	void __iomem *sensoraddr;
+
+	if (!ambient_light)
+		return -EINVAL;
+
+	if (!emp2 || !emp2->dev_en.is_als_present)
+		return -ENODEV;
+
+	sensoraddr = emp2->vsbase +
+		(ALS_IDX * SENSOR_DATA_MEM_SIZE_DEFAULT) +
+		OFFSET_SENSOR_DATA_DEFAULT;
+	memcpy_fromio(&als_data, sensoraddr, sizeof(struct sfh_als_data));
+	*ambient_light = amd_sfh_float_to_int(als_data.lux);
+
+	return 0;
+}
+
 int amd_get_sfh_info(struct amd_sfh_info *sfh_info, enum sfh_message_type op)
 {
 	if (sfh_info) {
 		switch (op) {
 		case MT_HPD:
 			return amd_sfh_hpd_info(&sfh_info->user_present);
+		case MT_ALS:
+			return amd_sfh_als_info(&sfh_info->ambient_light);
 		}
 	}
 	return -EINVAL;

include/linux/amd-pmf-io.h

@@ -17,9 +17,11 @@
 /**
  * enum sfh_message_type - Query the SFH message type
  * @MT_HPD: Message ID to know the Human presence info from MP2 FW
+ * @MT_ALS: Message ID to know the Ambient light info from MP2 FW
  */
 enum sfh_message_type {
 	MT_HPD,
+	MT_ALS,
 };
 
 /**
@@ -36,9 +38,11 @@ enum sfh_hpd_info {
 
 /**
  * struct amd_sfh_info - get HPD sensor info from MP2 FW
+ * @ambient_light: Populates the ambient light information
  * @user_present: Populates the user presence information
  */
 struct amd_sfh_info {
+	u32 ambient_light;
 	u8 user_present;
 };