From:   David Collins <quic_collinsd@quicinc.com>
To:     Daniel Lezcano <daniel.lezcano@linaro.org>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Amit Kucheria <amitk@kernel.org>,
        Thara Gopinath <thara.gopinath@gmail.com>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>
CC:     David Collins <quic_collinsd@quicinc.com>,
        Konrad Dybcio <konrad.dybcio@somainline.org>,
        Zhang Rui <rui.zhang@intel.com>,
        <linux-arm-msm@vger.kernel.org>, <linux-pm@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
Subject: [RESEND PATCH v3 3/3] thermal: qcom-spmi-temp-alarm: add support for LITE PMIC peripherals
Date:   Tue, 24 Jan 2023 15:46:06 -0800
Message-ID: <5fe697a29958813ce3c07104eb6f9d7a95b176ac.1674602698.git.quic_collinsd@quicinc.com>
In-Reply-To: <cover.1674602698.git.quic_collinsd@quicinc.com>
References: <cover.1674602698.git.quic_collinsd@quicinc.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
Precedence: bulk

Add support for TEMP_ALARM LITE PMIC peripherals.  This subtype
utilizes a pair of registers to configure a warning interrupt
threshold temperature and an automatic hardware shutdown
threshold temperature.

Signed-off-by: David Collins <quic_collinsd@quicinc.com>
---
 drivers/thermal/qcom/qcom-spmi-temp-alarm.c | 217 +++++++++++++++++++-
 1 file changed, 208 insertions(+), 9 deletions(-)

diff --git a/drivers/thermal/qcom/qcom-spmi-temp-alarm.c b/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
index 1fe8ff7a274e..dbf13dec7acd 100644
--- a/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
+++ b/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
@@ -4,6 +4,7 @@
  * Copyright (c) 2022, Qualcomm Innovation Center, Inc. All rights reserved.
  */
 
+#include <linux/bitfield.h>
 #include <linux/bitops.h>
 #include <linux/delay.h>
 #include <linux/err.h>
@@ -24,21 +25,28 @@
 #define QPNP_TM_REG_TYPE		0x04
 #define QPNP_TM_REG_SUBTYPE		0x05
 #define QPNP_TM_REG_STATUS		0x08
+#define QPNP_TM_REG_IRQ_STATUS		0x10
 #define QPNP_TM_REG_SHUTDOWN_CTRL1	0x40
 #define QPNP_TM_REG_ALARM_CTRL		0x46
 /* TEMP_DAC_* registers are only present for TEMP_GEN2 v2.0 */
 #define QPNP_TM_REG_TEMP_DAC_STG1	0x47
 #define QPNP_TM_REG_TEMP_DAC_STG2	0x48
 #define QPNP_TM_REG_TEMP_DAC_STG3	0x49
+#define QPNP_TM_REG_LITE_TEMP_CFG1	0x50
+#define QPNP_TM_REG_LITE_TEMP_CFG2	0x51
 
 #define QPNP_TM_TYPE			0x09
 #define QPNP_TM_SUBTYPE_GEN1		0x08
 #define QPNP_TM_SUBTYPE_GEN2		0x09
+#define QPNP_TM_SUBTYPE_LITE		0xC0
 
 #define STATUS_GEN1_STAGE_MASK		GENMASK(1, 0)
 #define STATUS_GEN2_STATE_MASK		GENMASK(6, 4)
 #define STATUS_GEN2_STATE_SHIFT		4
 
+/* IRQ status only needed for TEMP_ALARM_LITE */
+#define IRQ_STATUS_MASK			BIT(0)
+
 #define SHUTDOWN_CTRL1_OVERRIDE_S2	BIT(6)
 #define SHUTDOWN_CTRL1_THRESHOLD_MASK	GENMASK(1, 0)
 
@@ -46,6 +54,8 @@
 
 #define ALARM_CTRL_FORCE_ENABLE		BIT(7)
 
+#define LITE_TEMP_CFG_THRESHOLD_MASK	GENMASK(3, 2)
+
 #define THRESH_COUNT			4
 #define STAGE_COUNT			3
 
@@ -90,6 +100,19 @@ static const long temp_dac_max[STAGE_COUNT] = {
 	119375, 159375, 159375
 };
 
+/*
+ * TEMP_ALARM_LITE has two stages: warning and shutdown with independently
+ * configured threshold temperatures.
+ */
+
+static const long temp_map_lite_warning[THRESH_COUNT] = {
+	115000, 125000, 135000, 145000
+};
+
+static const long temp_map_lite_shutdown[THRESH_COUNT] = {
+	135000, 145000, 160000, 175000
+};
+
 /* Temperature in Milli Celsius reported during stage 0 if no ADC is present */
 #define DEFAULT_TEMP			37000
 
@@ -146,7 +169,7 @@ 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->has_temp_dac) {
+	if (chip->has_temp_dac || chip->subtype == QPNP_TM_SUBTYPE_LITE) {
 		if (stage == 0 || stage > STAGE_COUNT)
 			return 0;
 
@@ -164,19 +187,26 @@ static long qpnp_tm_decode_temp(struct qpnp_tm_chip *chip, unsigned int stage)
  * qpnp_tm_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 (GEN1), state (GEN2), or alarm interrupt state (LITE) on
+ *	   success; or errno on failure.
  */
 static int qpnp_tm_get_temp_stage(struct qpnp_tm_chip *chip)
 {
 	int ret;
+	u16 addr = QPNP_TM_REG_STATUS;
 	u8 reg = 0;
 
-	ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
+	if (chip->subtype == QPNP_TM_SUBTYPE_LITE)
+		addr = QPNP_TM_REG_IRQ_STATUS;
+
+	ret = qpnp_tm_read(chip, addr, &reg);
 	if (ret < 0)
 		return ret;
 
 	if (chip->subtype == QPNP_TM_SUBTYPE_GEN1)
 		ret = reg & STATUS_GEN1_STAGE_MASK;
+	else if (chip->subtype == QPNP_TM_SUBTYPE_LITE)
+		ret = reg & IRQ_STATUS_MASK;
 	else
 		ret = (reg & STATUS_GEN2_STATE_MASK) >> STATUS_GEN2_STATE_SHIFT;
 
@@ -199,7 +229,8 @@ static int qpnp_tm_update_temp_no_adc(struct qpnp_tm_chip *chip)
 		return ret;
 	stage = ret;
 
-	if (chip->subtype == QPNP_TM_SUBTYPE_GEN1) {
+	if (chip->subtype == QPNP_TM_SUBTYPE_GEN1
+	    || chip->subtype == QPNP_TM_SUBTYPE_LITE) {
 		stage_new = stage;
 		stage_old = chip->stage;
 	} else {
@@ -282,6 +313,78 @@ static int qpnp_tm_set_temp_dac_thresh(struct qpnp_tm_chip *chip, int trip,
 	return 0;
 }
 
+static int qpnp_tm_set_temp_lite_thresh(struct qpnp_tm_chip *chip, int trip,
+				       int temp)
+{
+	int ret, temp_cfg, i;
+	const long *temp_map;
+	u16 addr;
+	u8 reg, thresh;
+
+	if (trip < 0 || trip >= STAGE_COUNT) {
+		dev_err(chip->dev, "invalid TEMP_LITE trip = %d\n", trip);
+		return -EINVAL;
+	}
+
+	switch (trip) {
+	case 0:
+		temp_map = temp_map_lite_warning;
+		addr = QPNP_TM_REG_LITE_TEMP_CFG1;
+		break;
+	case 1:
+		/*
+		 * The second trip point is purely in software to facilitate
+		 * a controlled shutdown after the warning threshold is crossed
+		 * but before the automatic hardware shutdown threshold is
+		 * crossed.
+		 */
+		return 0;
+	case 2:
+		temp_map = temp_map_lite_shutdown;
+		addr = QPNP_TM_REG_LITE_TEMP_CFG2;
+		break;
+	default:
+		return 0;
+	}
+
+	if (temp < temp_map[THRESH_MIN] || temp > temp_map[THRESH_MAX]) {
+		dev_err(chip->dev, "invalid TEMP_LITE temp = %d\n", temp);
+		return -EINVAL;
+	}
+
+	thresh = 0;
+	temp_cfg = temp_map[thresh];
+	for (i = THRESH_MAX; i >= THRESH_MIN; i--) {
+		if (temp >= temp_map[i]) {
+			thresh = i;
+			temp_cfg = temp_map[i];
+			break;
+		}
+	}
+
+	if (temp_cfg == chip->temp_dac_map[trip])
+		return 0;
+
+	ret = qpnp_tm_read(chip, addr, &reg);
+	if (ret < 0) {
+		dev_err(chip->dev, "LITE_TEMP_CFG read failed, ret=%d\n", ret);
+		return ret;
+	}
+
+	reg &= ~LITE_TEMP_CFG_THRESHOLD_MASK;
+	reg |= FIELD_PREP(LITE_TEMP_CFG_THRESHOLD_MASK, thresh);
+
+	ret = qpnp_tm_write(chip, addr, reg);
+	if (ret < 0) {
+		dev_err(chip->dev, "LITE_TEMP_CFG write failed, ret=%d\n", ret);
+		return ret;
+	}
+
+	chip->temp_dac_map[trip] = temp_cfg;
+
+	return 0;
+}
+
 static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
 					     int temp)
 {
@@ -388,6 +491,24 @@ static const struct thermal_zone_device_ops qpnp_tm_sensor_temp_dac_ops = {
 	.set_trip_temp = qpnp_tm_set_temp_dac_trip_temp,
 };
 
+static int qpnp_tm_set_temp_lite_trip_temp(struct thermal_zone_device *tz,
+					   int trip, int temp)
+{
+	struct qpnp_tm_chip *chip = tz->devdata;
+	int ret;
+
+	mutex_lock(&chip->lock);
+	ret = qpnp_tm_set_temp_lite_thresh(chip, trip, temp);
+	mutex_unlock(&chip->lock);
+
+	return ret;
+}
+
+static const struct thermal_zone_device_ops qpnp_tm_sensor_temp_lite_ops = {
+	.get_temp = qpnp_tm_get_temp,
+	.set_trip_temp = qpnp_tm_set_temp_lite_trip_temp,
+};
+
 static irqreturn_t qpnp_tm_isr(int irq, void *data)
 {
 	struct qpnp_tm_chip *chip = data;
@@ -474,6 +595,71 @@ static int qpnp_tm_temp_dac_init(struct qpnp_tm_chip *chip)
 	return 0;
 }
 
+/* Configure TEMP_LITE registers based on DT thermal_zone trips */
+static int qpnp_tm_temp_lite_update_trip_temps(struct qpnp_tm_chip *chip)
+{
+	const struct thermal_trip *trips;
+	int ret, ntrips, i;
+
+	ntrips = of_thermal_get_ntrips(chip->tz_dev);
+	/* Keep hardware defaults if no DT trips are defined. */
+	if (ntrips <= 0)
+		return 0;
+
+	trips = of_thermal_get_trip_points(chip->tz_dev);
+	if (!trips)
+		return -EINVAL;
+
+	for (i = 0; i < ntrips; i++) {
+		if (of_thermal_is_trip_valid(chip->tz_dev, i)) {
+			ret = qpnp_tm_set_temp_lite_thresh(chip, i,
+							  trips[i].temperature);
+			if (ret < 0)
+				return ret;
+		}
+	}
+
+	/* Verify that trips are strictly increasing. */
+	if (chip->temp_dac_map[2] <= chip->temp_dac_map[0]) {
+		dev_err(chip->dev, "Threshold 2=%ld <= threshold 0=%ld\n",
+			chip->temp_dac_map[2], chip->temp_dac_map[0]);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* Read the hardware default TEMP_LITE stage threshold temperatures */
+static int qpnp_tm_temp_lite_init(struct qpnp_tm_chip *chip)
+{
+	int ret, thresh;
+	u8 reg = 0;
+
+	/*
+	 * Store the warning trip temp in temp_dac_map[0] and the shutdown trip
+	 * temp in temp_dac_map[2].  The second trip point is purely in software
+	 * to facilitate a controlled shutdown after the warning threshold is
+	 * crossed but before the automatic hardware shutdown threshold is
+	 * crossed.  Thus, there is no register to read for the second trip
+	 * point.
+	 */
+	ret = qpnp_tm_read(chip, QPNP_TM_REG_LITE_TEMP_CFG1, &reg);
+	if (ret < 0)
+		return ret;
+
+	thresh = FIELD_GET(LITE_TEMP_CFG_THRESHOLD_MASK, reg);
+	chip->temp_dac_map[0] = temp_map_lite_warning[thresh];
+
+	ret = qpnp_tm_read(chip, QPNP_TM_REG_LITE_TEMP_CFG2, &reg);
+	if (ret < 0)
+		return ret;
+
+	thresh = FIELD_GET(LITE_TEMP_CFG_THRESHOLD_MASK, reg);
+	chip->temp_dac_map[2] = temp_map_lite_shutdown[thresh];
+
+	return 0;
+}
+
 /*
  * This function initializes the internal temp value based on only the
  * current thermal stage and threshold. Setup threshold control and
@@ -500,13 +686,18 @@ static int qpnp_tm_init(struct qpnp_tm_chip *chip)
 		goto out;
 	chip->stage = ret;
 
-	stage = chip->subtype == QPNP_TM_SUBTYPE_GEN1
-		? chip->stage : alarm_state_map[chip->stage];
+	stage = (chip->subtype == QPNP_TM_SUBTYPE_GEN1
+		 || chip->subtype == QPNP_TM_SUBTYPE_LITE)
+			? chip->stage : alarm_state_map[chip->stage];
 
 	if (stage)
 		chip->temp = qpnp_tm_decode_temp(chip, stage);
 
-	if (chip->has_temp_dac) {
+	if (chip->subtype == QPNP_TM_SUBTYPE_LITE) {
+		ret = qpnp_tm_temp_lite_update_trip_temps(chip);
+		if (ret < 0)
+			goto out;
+	} else if (chip->has_temp_dac) {
 		ret = qpnp_tm_temp_dac_update_trip_temps(chip);
 		if (ret < 0)
 			goto out;
@@ -598,7 +789,8 @@ static int qpnp_tm_probe(struct platform_device *pdev)
 	chip->dig_revision = (dig_major << 8) | dig_minor;
 
 	if (type != QPNP_TM_TYPE || (subtype != QPNP_TM_SUBTYPE_GEN1
-				     && subtype != QPNP_TM_SUBTYPE_GEN2)) {
+				     && subtype != QPNP_TM_SUBTYPE_GEN2
+				     && subtype != QPNP_TM_SUBTYPE_LITE)) {
 		dev_err(&pdev->dev, "invalid type 0x%02x or subtype 0x%02x\n",
 			type, subtype);
 		return -ENODEV;
@@ -610,7 +802,7 @@ static int qpnp_tm_probe(struct platform_device *pdev)
 		chip->has_temp_dac = true;
 	else if (subtype == QPNP_TM_SUBTYPE_GEN2 && dig_major >= 1)
 		chip->temp_map = &temp_map_gen2_v1;
-	else
+	else if (subtype == QPNP_TM_SUBTYPE_GEN1)
 		chip->temp_map = &temp_map_gen1;
 
 	if (chip->has_temp_dac) {
@@ -620,6 +812,13 @@ static int qpnp_tm_probe(struct platform_device *pdev)
 			return ret;
 	}
 
+	if (chip->subtype == QPNP_TM_SUBTYPE_LITE) {
+		ops = &qpnp_tm_sensor_temp_lite_ops;
+		ret = qpnp_tm_temp_lite_init(chip);
+		if (ret < 0)
+			return ret;
+	}
+
 	/*
 	 * Register the sensor before initializing the hardware to be able to
 	 * read the trip points. get_temp() returns the default temperature
-- 
2.25.1