[PATCH 1/3] thermal: qcom-spmi-temp-alarm: enable stage 2 shutdown when required

[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>
---
 drivers/thermal/qcom/qcom-spmi-temp-alarm.c | 31 +++++++++++++++++++--
 1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/drivers/thermal/qcom/qcom-spmi-temp-alarm.c b/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
index 770f82cc9bca..91556118a7b8 100644
--- a/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
+++ b/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
@@ -18,6 +18,7 @@
 #include "../thermal_core.h"
 #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
@@ -73,6 +74,7 @@ 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;
@@ -224,6 +226,7 @@ static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
 	long stage2_threshold_min = (*chip->temp_map)[THRESH_MIN][1];
 	long stage2_threshold_max = (*chip->temp_map)[THRESH_MAX][1];
 	bool disable_s2_shutdown = false;
+	bool require_s2_shutdown = false;
 	u8 reg;
 
 	WARN_ON(!mutex_is_locked(&chip->lock));
@@ -255,9 +258,25 @@ static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
 				 "No ADC is configured and critical temperature is above the maximum stage 2 threshold of 140 C! Configuring stage 2 shutdown at 140 C.\n");
 	}
 
+	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:
+			require_s2_shutdown = true;
+			break;
+		}
+	}
+
 skip:
 	reg |= chip->thresh;
-	if (disable_s2_shutdown)
+	if (disable_s2_shutdown && !require_s2_shutdown)
 		reg |= SHUTDOWN_CTRL1_OVERRIDE_S2;
 
 	return qpnp_tm_write(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, reg);
@@ -372,7 +391,7 @@ 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;
 
@@ -428,6 +447,14 @@ static int qpnp_tm_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	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 (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",
-- 
2.25.1