thermal/drivers/qcom-spmi-temp-alarm: Add temp alarm data struct based on HW subtype

Currently multiple if/else statements are used in functions to decipher
between SPMI temp alarm Gen 1, Gen 2 and Gen 2 Rev 1 functionality. Instead
refactor the driver so that SPMI temp alarm chips will have reference to a
spmi_temp_alarm_data struct which defines data and function callbacks
based on the HW subtype.

Signed-off-by: Anjelique Melendez <anjelique.melendez@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20250710224555.3047790-3-anjelique.melendez@oss.qualcomm.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

drivers/thermal/qcom/qcom-spmi-temp-alarm.c

@@ -4,6 +4,7 @@
  * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
  */
 
+#include <linux/bitfield.h>
 #include <linux/bitops.h>
 #include <linux/delay.h>
 #include <linux/err.h>
@@ -31,7 +32,6 @@
 
 #define STATUS_GEN1_STAGE_MASK		GENMASK(1, 0)
 #define STATUS_GEN2_STATE_MASK		GENMASK(6, 4)
-#define STATUS_GEN2_STATE_SHIFT		4
 
 #define SHUTDOWN_CTRL1_OVERRIDE_STAGE2	BIT(6)
 #define SHUTDOWN_CTRL1_THRESHOLD_MASK	GENMASK(1, 0)
@@ -43,6 +43,12 @@
 #define THRESH_COUNT			4
 #define STAGE_COUNT			3
 
+enum overtemp_stage {
+	STAGE1 = 0,
+	STAGE2,
+	STAGE3,
+};
+
 /* Over-temperature trip point values in mC */
 static const long temp_map_gen1[THRESH_COUNT][STAGE_COUNT] = {
 	{ 105000, 125000, 145000 },
@@ -68,22 +74,29 @@ static const long temp_map_gen2_v1[THRESH_COUNT][STAGE_COUNT] = {
 /* Temperature in Milli Celsius reported during stage 0 if no ADC is present */
 #define DEFAULT_TEMP			37000
 
+struct qpnp_tm_chip;
+
+struct spmi_temp_alarm_data {
+	const long (*temp_map)[THRESH_COUNT][STAGE_COUNT];
+	int (*get_temp_stage)(struct qpnp_tm_chip *chip);
+};
+
 struct qpnp_tm_chip {
 	struct regmap			*map;
 	struct device			*dev;
 	struct thermal_zone_device	*tz_dev;
+	const struct spmi_temp_alarm_data *data;
 	unsigned int			subtype;
 	long				temp;
-	unsigned int			thresh;
 	unsigned int			stage;
 	unsigned int			base;
 	/* protects .thresh, .stage and chip registers */
 	struct mutex			lock;
 	bool				initialized;
 	bool				require_stage2_shutdown;
+	long				temp_thresh_map[STAGE_COUNT];
 
 	struct iio_channel		*adc;
-	const long			(*temp_map)[THRESH_COUNT][STAGE_COUNT];
 };
 
 /* This array maps from GEN2 alarm state to GEN1 alarm stage */
@@ -117,34 +130,48 @@ static int qpnp_tm_write(struct qpnp_tm_chip *chip, u16 addr, u8 data)
  */
 static long qpnp_tm_decode_temp(struct qpnp_tm_chip *chip, unsigned int stage)
 {
-	if (!chip->temp_map || chip->thresh >= THRESH_COUNT || stage == 0 ||
+	if (stage == 0 || stage > STAGE_COUNT)
-	    stage > STAGE_COUNT)
 		return 0;
 
-	return (*chip->temp_map)[chip->thresh][stage - 1];
+	return chip->temp_thresh_map[stage - 1];
 }
 
 /**
- * qpnp_tm_get_temp_stage() - return over-temperature stage
+ * qpnp_tm_gen1_get_temp_stage() - return over-temperature stage
  * @chip:		Pointer to the qpnp_tm chip
  *
- * Return: stage (GEN1) or state (GEN2) on success, or errno on failure.
+ * Return: stage on success, or errno on failure.
  */
-static int qpnp_tm_get_temp_stage(struct qpnp_tm_chip *chip)
+static int qpnp_tm_gen1_get_temp_stage(struct qpnp_tm_chip *chip)
 {
 	int ret;
-	u8 reg = 0;
+	u8 reg;
 
 	ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
 	if (ret < 0)
 		return ret;
 
-	if (chip->subtype == QPNP_TM_SUBTYPE_GEN1)
+	return FIELD_GET(STATUS_GEN1_STAGE_MASK, reg);
-		ret = reg & STATUS_GEN1_STAGE_MASK;
+}
-	else
-		ret = (reg & STATUS_GEN2_STATE_MASK) >> STATUS_GEN2_STATE_SHIFT;
 
-	return ret;
+/**
+ * qpnp_tm_gen2_get_temp_stage() - return over-temperature stage
+ * @chip:		Pointer to the qpnp_tm chip
+ *
+ * Return: stage on success, or errno on failure.
+ */
+static int qpnp_tm_gen2_get_temp_stage(struct qpnp_tm_chip *chip)
+{
+	int ret;
+	u8 reg;
+
+	ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
+	if (ret < 0)
+		return ret;
+
+	ret = FIELD_GET(STATUS_GEN2_STATE_MASK, reg);
+
+	return alarm_state_map[ret];
 }
 
 /*
@@ -153,23 +180,16 @@ static int qpnp_tm_get_temp_stage(struct qpnp_tm_chip *chip)
  */
 static int qpnp_tm_update_temp_no_adc(struct qpnp_tm_chip *chip)
 {
-	unsigned int stage, stage_new, stage_old;
+	unsigned int stage_new, stage_old;
 	int ret;
 
 	WARN_ON(!mutex_is_locked(&chip->lock));
 
-	ret = qpnp_tm_get_temp_stage(chip);
+	ret = chip->data->get_temp_stage(chip);
 	if (ret < 0)
 		return ret;
-	stage = ret;
+	stage_new = ret;
-
+	stage_old = chip->stage;
-	if (chip->subtype == QPNP_TM_SUBTYPE_GEN1) {
-		stage_new = stage;
-		stage_old = chip->stage;
-	} else {
-		stage_new = alarm_state_map[stage];
-		stage_old = alarm_state_map[chip->stage];
-	}
 
 	if (stage_new > stage_old) {
 		/* increasing stage, use lower bound */
@@ -181,7 +201,7 @@ static int qpnp_tm_update_temp_no_adc(struct qpnp_tm_chip *chip)
 				- TEMP_STAGE_HYSTERESIS;
 	}
 
-	chip->stage = stage;
+	chip->stage = stage_new;
 
 	return 0;
 }
@@ -221,10 +241,10 @@ static int qpnp_tm_get_temp(struct thermal_zone_device *tz, int *temp)
 static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
 					     int temp)
 {
-	long stage2_threshold_min = (*chip->temp_map)[THRESH_MIN][1];
+	long stage2_threshold_min = (*chip->data->temp_map)[THRESH_MIN][STAGE2];
-	long stage2_threshold_max = (*chip->temp_map)[THRESH_MAX][1];
+	long stage2_threshold_max = (*chip->data->temp_map)[THRESH_MAX][STAGE2];
 	bool disable_stage2_shutdown = false;
-	u8 reg;
+	u8 reg, threshold;
 
 	WARN_ON(!mutex_is_locked(&chip->lock));
 
@@ -236,17 +256,17 @@ static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
 
 	if (temp == THERMAL_TEMP_INVALID ||
 	    temp < stage2_threshold_min) {
-		chip->thresh = THRESH_MIN;
+		threshold = THRESH_MIN;
 		goto skip;
 	}
 
 	if (temp <= stage2_threshold_max) {
-		chip->thresh = THRESH_MAX -
+		threshold = THRESH_MAX -
 			((stage2_threshold_max - temp) /
 			 TEMP_THRESH_STEP);
 		disable_stage2_shutdown = true;
 	} else {
-		chip->thresh = THRESH_MAX;
+		threshold = THRESH_MAX;
 
 		if (chip->adc)
 			disable_stage2_shutdown = true;
@@ -257,7 +277,9 @@ static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
 	}
 
 skip:
-	reg |= chip->thresh;
+	memcpy(chip->temp_thresh_map, chip->data->temp_map[threshold],
+		sizeof(chip->temp_thresh_map));
+	reg |= threshold;
 	if (disable_stage2_shutdown && !chip->require_stage2_shutdown)
 		reg |= SHUTDOWN_CTRL1_OVERRIDE_STAGE2;
 
@@ -294,6 +316,21 @@ static irqreturn_t qpnp_tm_isr(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+static const struct spmi_temp_alarm_data spmi_temp_alarm_data = {
+	.temp_map = &temp_map_gen1,
+	.get_temp_stage = qpnp_tm_gen1_get_temp_stage,
+};
+
+static const struct spmi_temp_alarm_data spmi_temp_alarm_gen2_data = {
+	.temp_map = &temp_map_gen1,
+	.get_temp_stage = qpnp_tm_gen2_get_temp_stage,
+};
+
+static const struct spmi_temp_alarm_data spmi_temp_alarm_gen2_rev1_data = {
+	.temp_map = &temp_map_gen2_v1,
+	.get_temp_stage = qpnp_tm_gen2_get_temp_stage,
+};
+
 /*
  * This function initializes the internal temp value based on only the
  * current thermal stage and threshold. Setup threshold control and
@@ -301,10 +338,10 @@ static irqreturn_t qpnp_tm_isr(int irq, void *data)
  */
 static int qpnp_tm_init(struct qpnp_tm_chip *chip)
 {
-	unsigned int stage;
-	int ret;
-	u8 reg = 0;
 	int crit_temp;
+	u8 threshold;
+	int ret;
+	u8 reg;
 
 	mutex_lock(&chip->lock);
 
@@ -312,19 +349,19 @@ static int qpnp_tm_init(struct qpnp_tm_chip *chip)
 	if (ret < 0)
 		goto out;
 
-	chip->thresh = reg & SHUTDOWN_CTRL1_THRESHOLD_MASK;
+	threshold = reg & SHUTDOWN_CTRL1_THRESHOLD_MASK;
+	memcpy(chip->temp_thresh_map, chip->data->temp_map[threshold],
+		sizeof(chip->temp_thresh_map));
+
 	chip->temp = DEFAULT_TEMP;
 
-	ret = qpnp_tm_get_temp_stage(chip);
+	ret = chip->data->get_temp_stage(chip);
 	if (ret < 0)
 		goto out;
 	chip->stage = ret;
 
-	stage = chip->subtype == QPNP_TM_SUBTYPE_GEN1
+	if (chip->stage)
-		? chip->stage : alarm_state_map[chip->stage];
+		chip->temp = qpnp_tm_decode_temp(chip, chip->stage);
-
-	if (stage)
-		chip->temp = qpnp_tm_decode_temp(chip, stage);
 
 	mutex_unlock(&chip->lock);
 
@@ -418,10 +455,14 @@ static int qpnp_tm_probe(struct platform_device *pdev)
 	}
 
 	chip->subtype = subtype;
-	if (subtype == QPNP_TM_SUBTYPE_GEN2 && dig_major >= 1)
+	if (subtype == QPNP_TM_SUBTYPE_GEN1)
-		chip->temp_map = &temp_map_gen2_v1;
+		chip->data = &spmi_temp_alarm_data;
+	else if (subtype == QPNP_TM_SUBTYPE_GEN2 && dig_major == 0)
+		chip->data = &spmi_temp_alarm_gen2_data;
+	else if (subtype == QPNP_TM_SUBTYPE_GEN2 && dig_major >= 1)
+		chip->data = &spmi_temp_alarm_gen2_rev1_data;
 	else
-		chip->temp_map = &temp_map_gen1;
+		return -ENODEV;
 
 	if (chip->subtype == QPNP_TM_SUBTYPE_GEN2) {
 		dig_revision = (dig_major << 8) | dig_minor;