[PATCH 3/5] thermal: qcom-spmi-temp-alarm: enable stage 2 shutdown when required

[Anjelique Melendez <quic_amelende@quicinc.com>]

From: David Collins <quic_collinsd@quicinc.com>

Certain TEMP_ALARM GEN2 PMIC peripherals need over-temperature
stage 2 automatic PMIC partial shutdown to be enabled in order to
avoid repeated faults in the event of reaching over-temperature
stage 3.  Modify the stage 2 shutdown control logic to ensure that
stage 2 shutdown is enabled on all affected PMICs.  Read the
digital major and minor revision registers to identify these
PMICs.

Signed-off-by: David Collins <quic_collinsd@quicinc.com>
Signed-off-by: Anjelique Melendez <quic_amelende@quicinc.com>
---
 drivers/thermal/qcom/qcom-spmi-temp-alarm.c | 32 +++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/drivers/thermal/qcom/qcom-spmi-temp-alarm.c b/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
index 96daad28b0c0..de4a2d99f0d5 100644
--- a/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
+++ b/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (c) 2011-2015, 2017, 2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved.
  */
 
 #include <linux/bitops.h>
@@ -16,6 +17,7 @@
 
 #include "../thermal_hwmon.h"
 
+#define QPNP_TM_REG_DIG_MINOR		0x00
 #define QPNP_TM_REG_DIG_MAJOR		0x01
 #define QPNP_TM_REG_TYPE		0x04
 #define QPNP_TM_REG_SUBTYPE		0x05
@@ -71,6 +73,7 @@ struct qpnp_tm_chip {
 	struct device			*dev;
 	struct thermal_zone_device	*tz_dev;
 	unsigned int			subtype;
+	unsigned int			dig_revision;
 	long				temp;
 	unsigned int			thresh;
 	unsigned int			stage;
@@ -78,6 +81,7 @@ struct qpnp_tm_chip {
 	/* protects .thresh, .stage and chip registers */
 	struct mutex			lock;
 	bool				initialized;
+	bool				require_s2_shutdown;
 
 	struct iio_channel		*adc;
 	const long			(*temp_map)[THRESH_COUNT][STAGE_COUNT];
@@ -255,7 +259,7 @@ static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
 
 skip:
 	reg |= chip->thresh;
-	if (disable_s2_shutdown)
+	if (disable_s2_shutdown && !chip->require_s2_shutdown)
 		reg |= SHUTDOWN_CTRL1_OVERRIDE_S2;
 
 	return qpnp_tm_write(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, reg);
@@ -366,7 +370,7 @@ static int qpnp_tm_probe(struct platform_device *pdev)
 {
 	struct qpnp_tm_chip *chip;
 	struct device_node *node;
-	u8 type, subtype, dig_major;
+	u8 type, subtype, dig_major, dig_minor;
 	u32 res;
 	int ret, irq;
 
@@ -419,6 +423,30 @@ static int qpnp_tm_probe(struct platform_device *pdev)
 		return dev_err_probe(&pdev->dev, ret,
 				     "could not read dig_major\n");
 
+	ret = qpnp_tm_read(chip, QPNP_TM_REG_DIG_MINOR, &dig_minor);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "could not read dig_minor\n");
+		return ret;
+	}
+
+	chip->dig_revision = (dig_major << 8) | dig_minor;
+
+	if (chip->subtype == QPNP_TM_SUBTYPE_GEN2) {
+		/*
+		 * Check if stage 2 automatic partial shutdown must remain
+		 * enabled to avoid potential repeated faults upon reaching
+		 * over-temperature stage 3.
+		 */
+		switch (chip->dig_revision) {
+		case 0x0001:
+		case 0x0002:
+		case 0x0100:
+		case 0x0101:
+			chip->require_s2_shutdown = true;
+			break;
+		}
+	}
+
 	if (type != QPNP_TM_TYPE || (subtype != QPNP_TM_SUBTYPE_GEN1
 				     && subtype != QPNP_TM_SUBTYPE_GEN2)) {
 		dev_err(&pdev->dev, "invalid type 0x%02x or subtype 0x%02x\n",
-- 
2.34.1