thermal/drivers/mediatek/lvts: Make number of calibration offsets configurable

MT8196/MT6991 use 2-byte eFuse calibration data, whereas other SoCs
supported by the driver rely on 3 bytes. Make the number of calibration
bytes per sensor configurable, enabling support for SoCs with varying
calibration formats.

Signed-off-by: Laura Nao <laura.nao@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patch.msgid.link/20251125-mt8196-lvts-v4-v5-2-6db7eb903fb7@collabora.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

Author: laura-nao

drivers/thermal/mediatek/lvts_thermal.c

@@ -96,12 +96,15 @@
 
 #define LVTS_MINIMUM_THRESHOLD		20000
 
+#define LVTS_MAX_CAL_OFFSETS		3
+#define LVTS_NUM_CAL_OFFSETS_MT7988	3
+
 static int golden_temp = LVTS_GOLDEN_TEMP_DEFAULT;
 static int golden_temp_offset;
 
 struct lvts_sensor_data {
 	int dt_id;
-	u8 cal_offsets[3];
+	u8 cal_offsets[LVTS_MAX_CAL_OFFSETS];
 };
 
 struct lvts_ctrl_data {
@@ -127,6 +130,7 @@ struct lvts_data {
 	const struct lvts_ctrl_data *lvts_ctrl;
 	const u32 *conn_cmd;
 	const u32 *init_cmd;
+	int num_cal_offsets;
 	int num_lvts_ctrl;
 	int num_conn_cmd;
 	int num_init_cmd;
@@ -646,6 +650,26 @@ static int lvts_sensor_init(struct device *dev, struct lvts_ctrl *lvts_ctrl,
 	return 0;
 }
 
+static int lvts_decode_sensor_calibration(const struct lvts_sensor_data *sensor,
+					const u8 *efuse_calibration, u32 calib_len,
+					u8 num_offsets, u32 *calib)
+{
+	int i;
+	u32 calib_val = 0;
+
+	for (i = 0; i < num_offsets; i++) {
+		u8 offset = sensor->cal_offsets[i];
+
+		if (offset >= calib_len)
+			return -EINVAL;
+		// Pack each calibration byte into the correct position
+		calib_val |= efuse_calibration[offset] << (8 * i);
+	}
+
+	*calib = calib_val;
+	return 0;
+}
+
 /*
  * The efuse blob values follows the sensor enumeration per thermal
  * controller. The decoding of the stream is as follow:
@@ -711,26 +735,27 @@ static int lvts_calibration_init(struct device *dev, struct lvts_ctrl *lvts_ctrl
 					u8 *efuse_calibration,
 					size_t calib_len)
 {
-	int i;
+	const struct lvts_data *lvts_data = lvts_ctrl->lvts_data;
+	int i, ret;
 	u32 gt;
 
 	/* A zero value for gt means that device has invalid efuse data */
-	gt = (((u32 *)efuse_calibration)[0] >> lvts_ctrl->lvts_data->gt_calib_bit_offset) & 0xff;
+	gt = (((u32 *)efuse_calibration)[0] >> lvts_data->gt_calib_bit_offset) & 0xff;
 
 	lvts_for_each_valid_sensor(i, lvts_ctrl_data) {
 		const struct lvts_sensor_data *sensor =
 					&lvts_ctrl_data->lvts_sensor[i];
+		u32 calib = 0;
 
-		if (sensor->cal_offsets[0] >= calib_len ||
-		    sensor->cal_offsets[1] >= calib_len ||
-		    sensor->cal_offsets[2] >= calib_len)
-			return -EINVAL;
+		ret = lvts_decode_sensor_calibration(sensor, efuse_calibration,
+						     calib_len,
+						     lvts_data->num_cal_offsets,
+						     &calib);
+		if (ret)
+			return ret;
 
 		if (gt) {
-			lvts_ctrl->calibration[i] =
-				(efuse_calibration[sensor->cal_offsets[0]] << 0) +
-				(efuse_calibration[sensor->cal_offsets[1]] << 8) +
-				(efuse_calibration[sensor->cal_offsets[2]] << 16);
+			lvts_ctrl->calibration[i] = calib;
 		} else if (lvts_ctrl->lvts_data->def_calibration) {
 			lvts_ctrl->calibration[i] = lvts_ctrl->lvts_data->def_calibration;
 		} else {
@@ -1763,6 +1788,7 @@ static const struct lvts_data mt7988_lvts_ap_data = {
 	.temp_factor	= LVTS_COEFF_A_MT7988,
 	.temp_offset	= LVTS_COEFF_B_MT7988,
 	.gt_calib_bit_offset = 24,
+	.num_cal_offsets = LVTS_NUM_CAL_OFFSETS_MT7988,
 };
 
 static const struct lvts_data mt8186_lvts_data = {
@@ -1776,6 +1802,7 @@ static const struct lvts_data mt8186_lvts_data = {
 	.temp_offset	= LVTS_COEFF_B_MT7988,
 	.gt_calib_bit_offset = 24,
 	.def_calibration = 19000,
+	.num_cal_offsets = LVTS_NUM_CAL_OFFSETS_MT7988,
 };
 
 static const struct lvts_data mt8188_lvts_mcu_data = {
@@ -1789,6 +1816,7 @@ static const struct lvts_data mt8188_lvts_mcu_data = {
 	.temp_offset	= LVTS_COEFF_B_MT8195,
 	.gt_calib_bit_offset = 20,
 	.def_calibration = 35000,
+	.num_cal_offsets = LVTS_NUM_CAL_OFFSETS_MT7988,
 };
 
 static const struct lvts_data mt8188_lvts_ap_data = {
@@ -1802,6 +1830,7 @@ static const struct lvts_data mt8188_lvts_ap_data = {
 	.temp_offset	= LVTS_COEFF_B_MT8195,
 	.gt_calib_bit_offset = 20,
 	.def_calibration = 35000,
+	.num_cal_offsets = LVTS_NUM_CAL_OFFSETS_MT7988,
 };
 
 static const struct lvts_data mt8192_lvts_mcu_data = {
@@ -1815,6 +1844,7 @@ static const struct lvts_data mt8192_lvts_mcu_data = {
 	.temp_offset	= LVTS_COEFF_B_MT8195,
 	.gt_calib_bit_offset = 24,
 	.def_calibration = 35000,
+	.num_cal_offsets = LVTS_NUM_CAL_OFFSETS_MT7988,
 };
 
 static const struct lvts_data mt8192_lvts_ap_data = {
@@ -1828,6 +1858,7 @@ static const struct lvts_data mt8192_lvts_ap_data = {
 	.temp_offset	= LVTS_COEFF_B_MT8195,
 	.gt_calib_bit_offset = 24,
 	.def_calibration = 35000,
+	.num_cal_offsets = LVTS_NUM_CAL_OFFSETS_MT7988,
 };
 
 static const struct lvts_data mt8195_lvts_mcu_data = {
@@ -1841,6 +1872,7 @@ static const struct lvts_data mt8195_lvts_mcu_data = {
 	.temp_offset	= LVTS_COEFF_B_MT8195,
 	.gt_calib_bit_offset = 24,
 	.def_calibration = 35000,
+	.num_cal_offsets = LVTS_NUM_CAL_OFFSETS_MT7988,
 };
 
 static const struct lvts_data mt8195_lvts_ap_data = {
@@ -1854,6 +1886,7 @@ static const struct lvts_data mt8195_lvts_ap_data = {
 	.temp_offset	= LVTS_COEFF_B_MT8195,
 	.gt_calib_bit_offset = 24,
 	.def_calibration = 35000,
+	.num_cal_offsets = LVTS_NUM_CAL_OFFSETS_MT7988,
 };
 
 static const struct of_device_id lvts_of_match[] = {