[PATCH v5 0/3] Lenovo ThinkPad T14s EC thermal monitoring and thermal zone integration

[PATCH v5 0/3] Lenovo ThinkPad T14s EC thermal monitoring and thermal zone integration

[Daniel Lezcano]

Hi,

This series extends the Lenovo ThinkPad T14s embedded controller driver
with environmental monitoring capabilities and integrates the exposed
sensors into the Linux thermal framework.

The EC provides access to several platform temperature sensors
covering the SoC, keyboard area, bottom cover, charging circuitry, QTM
module and SSD. These sensors are currently used by the firmware for
thermal management but are not exposed to Linux.

The first patch adds hwmon support for the EC temperature sensors.

The second patch exposes the EC as a thermal sensor provider in the
device tree and defines thermal zones for the keyboard skin
temperature and the charging circuitry temperature. This allows the
generic thermal framework to react to EC-reported temperatures and
apply standard Linux thermal mitigation policies.

As the EC protocol is not fully decoded, the passive trip points
get/set actions are missing, so it is not possible to program a
threshold and receive an interrupt when crossed the way up or
down. Consequently, the thermal zone related to the charging circuitry
is polled every two seconds until we can set the trip points in the
EC.

This series fixes critical thermal issues happening on this platform
where a kernel compilation, or heavy workloads, lead to a system
reboot.

Tested on a Lenovo ThinkPad T14s Gen 6 (Snapdragon X Elite).

Please make sure scmi-cpufreq.ko is loaded before testing

Thanks,

Daniel

---
 Changelog:
	v5:
	 - Added Reviewed-by tag (Ilpo Järvinen)
	 - Added the '#thermal-sensor-cells' property DT binding (Sashiko)
	v4:
 	 - Added the missing HWMON_C_REGISTER_TZ attribute (Sashiko)
	 - Fixed dependency with HWMON (Sashiko)
	 - Added tags
	v3:
	 - Removed event based because trip point are not yet well supported
	 - Added an empty line after variable declaration (Ilpo Järvinen)
	 - Used MILLIDEGREE_PER_DEGREE from units.h (Ilpo Järvinen)
	 - Made switch consistent (Ilpo Järvinen)
	v2:
	 - Fixed patch 1 subject prefix
	 - Removed the fan information part
	 - Added HWMON_T_ALARM
	 - Fixed DT change description to reflect what it does really

Daniel Lezcano (3):
  dt-bindings: embedded-controller: Add Lenovo ThinkPad T14s thermal
    sensor provider support
  platform: arm64: lenovo-thinkpad-t14s-ec: Add hwmon support for
    temperatures
  arm64: dts: qcom: x1e78100-t14s: Add thermal zones for keyboard skin
    and charging sensors

 .../lenovo,thinkpad-t14s-ec.yaml              |   5 +
 .../qcom/x1e78100-lenovo-thinkpad-t14s.dtsi   |  67 ++++++++-
 drivers/platform/arm64/Kconfig                |   1 +
 drivers/platform/arm64/lenovo-thinkpad-t14s.c | 131 ++++++++++++++++++
 4 files changed, 203 insertions(+), 1 deletion(-)

-- 
2.53.0

[PATCH v5 1/3] dt-bindings: embedded-controller: Add Lenovo ThinkPad T14s thermal sensor provider support

[Daniel Lezcano]

Document the Lenovo ThinkPad T14s Embedded Controller as a thermal
sensor provider by adding the '#thermal-sensor-cells' property.

This allows the EC temperature sensors to be referenced from thermal
zones in the device tree.

Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
---
 .../embedded-controller/lenovo,thinkpad-t14s-ec.yaml         | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
index c87ccb5b3086..0d049979e35b 100644
--- a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
+++ b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
@@ -26,10 +26,14 @@ properties:
 
   wakeup-source: true
 
+  "#thermal-sensor-cells":
+    const: 1
+
 required:
   - compatible
   - reg
   - interrupts
+  - "#thermal-sensor-cells"
 
 additionalProperties: false
 
@@ -45,6 +49,7 @@ examples:
             reg = <0x28>;
             interrupts-extended = <&tlmm 66 IRQ_TYPE_LEVEL_LOW>;
             wakeup-source;
+            #thermal-sensor-cells = <1>;
         };
     };
 ...
-- 
2.53.0

[PATCH v5 2/3] platform: arm64: lenovo-thinkpad-t14s-ec: Add hwmon support for temperatures

[Daniel Lezcano]

Expose the Lenovo ThinkPad T14s EC environmental sensors through
the hwmon subsystem.

The driver now registers a hwmon device providing access to six EC
temperature sensors corresponding to the SoC, keyboard area, base
cover, PMIC/charging circuitry, QTM module and SSD. Sensor labels
are exported to allow user space to identify each measurement.

This allows standard monitoring tools such as lm-sensors to report
platform temperatures.

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on T14s OLED
Signed-off-by: Daniel Lezcano daniel.lezcano@oss.qualcomm.com
---
 drivers/platform/arm64/Kconfig                |   1 +
 drivers/platform/arm64/lenovo-thinkpad-t14s.c | 131 ++++++++++++++++++
 2 files changed, 132 insertions(+)

diff --git a/drivers/platform/arm64/Kconfig b/drivers/platform/arm64/Kconfig
index 10f905d7d6bf..121043348740 100644
--- a/drivers/platform/arm64/Kconfig
+++ b/drivers/platform/arm64/Kconfig
@@ -75,6 +75,7 @@ config EC_LENOVO_THINKPAD_T14S
 	depends on ARCH_QCOM || COMPILE_TEST
 	depends on I2C
 	depends on INPUT
+	depends on HWMON
 	select INPUT_SPARSEKMAP
 	select LEDS_CLASS
 	select NEW_LEDS
diff --git a/drivers/platform/arm64/lenovo-thinkpad-t14s.c b/drivers/platform/arm64/lenovo-thinkpad-t14s.c
index 5590302a5694..fc480f093238 100644
--- a/drivers/platform/arm64/lenovo-thinkpad-t14s.c
+++ b/drivers/platform/arm64/lenovo-thinkpad-t14s.c
@@ -11,6 +11,7 @@
 #include <linux/delay.h>
 #include <linux/dev_printk.h>
 #include <linux/err.h>
+#include <linux/hwmon.h>
 #include <linux/i2c.h>
 #include <linux/input.h>
 #include <linux/input/sparse-keymap.h>
@@ -21,6 +22,7 @@
 #include <linux/regmap.h>
 #include <linux/slab.h>
 #include <linux/pm.h>
+#include <linux/units.h>
 
 #define T14S_EC_CMD_ECRD	0x02
 #define T14S_EC_CMD_ECWR	0x03
@@ -67,6 +69,13 @@
 #define T14S_EC_EVT_KEY_FN_F11			0x7a
 #define T14S_EC_EVT_KEY_FN_G			0x7e
 
+#define T14S_EC_SYS_THERM0 0x78 /* SoC (CPU+GPU)  */
+#define T14S_EC_SYS_THERM1 0x79 /* Keyboard       */
+#define T14S_EC_SYS_THERM2 0x7a /* Back cover     */
+#define T14S_EC_SYS_THERM3 0x7b /* Charger / PMIC */
+#define T14S_EC_SYS_THERM6 0x7c /* QTM West       */
+#define T14S_EC_SYS_THERM7 0x7d /* SSD            */
+
 /* Hardware LED blink rate is 1 Hz (500ms off, 500ms on) */
 #define T14S_EC_BLINK_RATE_ON_OFF_MS		500
 
@@ -93,9 +102,19 @@ struct t14s_ec_led_classdev {
 	struct t14s_ec *ec;
 };
 
+struct t14s_ec_hwmon_sys_thermx {
+	const char *label;
+	int reg;
+};
+
+struct t14s_ec_hwmon {
+	struct t14s_ec_hwmon_sys_thermx *sys_thermx;
+};
+
 struct t14s_ec {
 	struct regmap *regmap;
 	struct device *dev;
+	struct t14s_ec_hwmon ec_hwmon;
 	struct t14s_ec_led_classdev led_pwr_btn;
 	struct t14s_ec_led_classdev led_chrg_orange;
 	struct t14s_ec_led_classdev led_chrg_white;
@@ -555,6 +574,114 @@ static irqreturn_t t14s_ec_irq_handler(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+static umode_t t14s_ec_hwmon_is_visible(const void *drvdata,
+					enum hwmon_sensor_types type,
+					u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_temp:
+		if (attr == hwmon_temp_input ||
+		    attr == hwmon_temp_label)
+			return 0444;
+		break;
+	default:
+		return 0;
+	}
+
+	return 0;
+}
+
+static int t14s_ec_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type,
+				     u32 attr, int channel, const char **str)
+{
+	struct t14s_ec *ec = dev_get_drvdata(dev);
+
+	switch (type) {
+	case hwmon_temp:
+		if (attr == hwmon_temp_label) {
+			*str = ec->ec_hwmon.sys_thermx[channel].label;
+			return 0;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int t14s_ec_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+			      u32 attr, int channel, long *val)
+{
+	struct t14s_ec *ec = dev_get_drvdata(dev);
+	unsigned int value;
+	int ret;
+
+	switch (type) {
+	case hwmon_temp:
+		if (attr == hwmon_temp_input) {
+			ret = t14s_ec_read(ec, ec->ec_hwmon.sys_thermx[channel].reg, &value);
+			if (ret)
+				return ret;
+			*val = value * MILLIDEGREE_PER_DEGREE;
+
+			return 0;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static const struct hwmon_ops t14s_ec_hwmon_ops = {
+	.is_visible = t14s_ec_hwmon_is_visible,
+	.read = t14s_ec_hwmon_read,
+	.read_string = t14s_ec_hwmon_read_string,
+};
+
+static const struct hwmon_channel_info *t14s_ec_hwmon_info[] = {
+	HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL),
+	NULL
+};
+
+static const struct hwmon_chip_info t14s_ec_chip_info = {
+	.ops = &t14s_ec_hwmon_ops,
+	.info = t14s_ec_hwmon_info,
+};
+
+static int t14s_ec_hwmon_probe(struct t14s_ec *ec)
+{
+	struct device *dev;
+	struct t14s_ec_hwmon_sys_thermx sys_thermx[] = {
+		{ .label = "soc",	.reg = T14S_EC_SYS_THERM0 },
+		{ .label = "keyboard",	.reg = T14S_EC_SYS_THERM1 },
+		{ .label = "base",	.reg = T14S_EC_SYS_THERM2 },
+		{ .label = "charging",	.reg = T14S_EC_SYS_THERM3 },
+		{ .label = "qtm",	.reg = T14S_EC_SYS_THERM6 },
+		{ .label = "ssd",	.reg = T14S_EC_SYS_THERM7 },
+	};
+
+	ec->ec_hwmon.sys_thermx = devm_kmemdup_array(ec->dev, sys_thermx,
+						     ARRAY_SIZE(sys_thermx),
+						     sizeof(sys_thermx[0]), GFP_KERNEL);
+	if (!ec->ec_hwmon.sys_thermx)
+		return -ENOMEM;
+
+	dev = devm_hwmon_device_register_with_info(ec->dev, "t14s_ec", ec,
+						   &t14s_ec_chip_info, NULL);
+
+	return PTR_ERR_OR_ZERO(dev);
+}
+
 static int t14s_ec_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
@@ -590,6 +717,10 @@ static int t14s_ec_probe(struct i2c_client *client)
 	if (ret < 0)
 		return ret;
 
+	ret = t14s_ec_hwmon_probe(ec);
+	if (ret < 0)
+		return ret;
+
 	ret = devm_request_threaded_irq(dev, client->irq, NULL,
 					t14s_ec_irq_handler,
 					IRQF_ONESHOT, dev_name(dev), ec);
-- 
2.53.0

[PATCH v5 3/3] arm64: dts: qcom: x1e78100-t14s: Add thermal zones for keyboard skin and charging sensors

[Daniel Lezcano]

The Lenovo ThinkPad T14s embedded controller exposes several platform
temperature sensors that are already used by the firmware for thermal
management.

Expose the EC as a thermal sensor provider and describe the keyboard
skin and charging circuitry sensors as thermal zones in the device
tree.

The keyboard thermal zone defines passive and hot trip points, while
the charging thermal zone also associates a cooling map with the CPU
clusters, allowing the generic thermal framework to apply CPU
throttling when the charging circuitry temperature exceeds the passive
threshold.

This integrates the EC temperature sensors with the Linux thermal
framework and enables platform thermal management using standard
thermal zone definitions.

The EC protocol currently does not provide a mechanism to program trip
points from Linux. Consequently, the thermal zones rely on periodic
polling to detect threshold crossings.

Using the charging circuitry temperature for thermal mitigation provides
a conservative approximation of the platform thermal state and prevents
the platform from reaching critical temperatures under sustained heavy
CPU load.

Without this change the platform reaches a critical thermal condition
and resets under heavy load.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on T14s OLED
Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
---
 .../qcom/x1e78100-lenovo-thinkpad-t14s.dtsi   | 67 ++++++++++++++++++-
 1 file changed, 66 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi
index 5d49df41be02..ed5ba3a428a8 100644
--- a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi
+++ b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi
@@ -979,7 +979,7 @@ &i2c6 {
 
 	status = "okay";
 
-	embedded-controller@28 {
+	ec: embedded-controller@28 {
 		compatible = "lenovo,thinkpad-t14s-ec";
 		reg = <0x28>;
 
@@ -988,6 +988,8 @@ embedded-controller@28 {
 		pinctrl-0 = <&ec_int_n_default>;
 		pinctrl-names = "default";
 
+		#thermal-sensor-cells = <1>;
+
 		wakeup-source;
 	};
 };
@@ -1729,3 +1731,66 @@ &usb_mp_qmpphy1 {
 
 	status = "okay";
 };
+
+&thermal_zones {
+	ec-keyboard-thermal {
+		polling-delay = <5000>;
+		polling-delay-passive = <1000>;
+
+		thermal-sensors = <&ec 1>;
+
+		trips {
+			trip-point0 {
+				temperature = <55000>;
+				hysteresis = <2000>;
+				type = "passive";
+			};
+
+			trip-point1 {
+				temperature = <62000>;
+				hysteresis = <0>;
+				type = "hot";
+			};
+		};
+	};
+
+	ec-charging-thermal {
+		/* EC trip points cannot yet be programmed. */
+		polling-delay = <5000>;
+		polling-delay-passive = <2000>;
+
+		thermal-sensors = <&ec 3>;
+
+		trips {
+			ec_charging_psv0: trip-point0 {
+				temperature = <55000>;
+				hysteresis = <0>;
+				type = "passive";
+			};
+
+			ec_charging_alrt0: trip-point1 {
+				temperature = <63000>;
+				hysteresis = <0>;
+				type = "hot";
+			};
+		};
+
+		cooling-maps {
+			map0 {
+				trip = <&ec_charging_psv0>;
+				cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu4 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu5 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu6 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu7 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+						 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+			};
+		};
+	};
+};
-- 
2.53.0

Re: [PATCH v5 3/3] arm64: dts: qcom: x1e78100-t14s: Add thermal zones for keyboard skin and charging sensors

[Dmitry Baryshkov]

On Mon, Jul 06, 2026 at 08:46:48PM +0200, Daniel Lezcano wrote:
> The Lenovo ThinkPad T14s embedded controller exposes several platform
> temperature sensors that are already used by the firmware for thermal
> management.
> 
> Expose the EC as a thermal sensor provider and describe the keyboard
> skin and charging circuitry sensors as thermal zones in the device
> tree.
> 
> The keyboard thermal zone defines passive and hot trip points, while
> the charging thermal zone also associates a cooling map with the CPU
> clusters, allowing the generic thermal framework to apply CPU
> throttling when the charging circuitry temperature exceeds the passive
> threshold.
> 
> This integrates the EC temperature sensors with the Linux thermal
> framework and enables platform thermal management using standard
> thermal zone definitions.
> 
> The EC protocol currently does not provide a mechanism to program trip
> points from Linux. Consequently, the thermal zones rely on periodic
> polling to detect threshold crossings.
> 
> Using the charging circuitry temperature for thermal mitigation provides
> a conservative approximation of the platform thermal state and prevents
> the platform from reaching critical temperatures under sustained heavy
> CPU load.
> 
> Without this change the platform reaches a critical thermal condition
> and resets under heavy load.
> 
> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
> Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on T14s OLED
> Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
> ---
>  .../qcom/x1e78100-lenovo-thinkpad-t14s.dtsi   | 67 ++++++++++++++++++-
>  1 file changed, 66 insertions(+), 1 deletion(-)

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

> 
-- 
With best wishes
Dmitry

Re: [PATCH v5 2/3] platform: arm64: lenovo-thinkpad-t14s-ec: Add hwmon support for temperatures

[Dmitry Baryshkov]

On Mon, Jul 06, 2026 at 08:46:47PM +0200, Daniel Lezcano wrote:
> Expose the Lenovo ThinkPad T14s EC environmental sensors through
> the hwmon subsystem.
> 
> The driver now registers a hwmon device providing access to six EC
> temperature sensors corresponding to the SoC, keyboard area, base
> cover, PMIC/charging circuitry, QTM module and SSD. Sensor labels
> are exported to allow user space to identify each measurement.
> 
> This allows standard monitoring tools such as lm-sensors to report
> platform temperatures.
> 
> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on T14s OLED
> Signed-off-by: Daniel Lezcano daniel.lezcano@oss.qualcomm.com
> ---
>  drivers/platform/arm64/Kconfig                |   1 +
>  drivers/platform/arm64/lenovo-thinkpad-t14s.c | 131 ++++++++++++++++++
>  2 files changed, 132 insertions(+)
> 

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>


-- 
With best wishes
Dmitry

Re: [PATCH v5 1/3] dt-bindings: embedded-controller: Add Lenovo ThinkPad T14s thermal sensor provider support

[Krzysztof Kozlowski]

On Mon, Jul 06, 2026 at 08:46:46PM +0200, Daniel Lezcano wrote:
> Document the Lenovo ThinkPad T14s Embedded Controller as a thermal
> sensor provider by adding the '#thermal-sensor-cells' property.
> 
> This allows the EC temperature sensors to be referenced from thermal
> zones in the device tree.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
> ---
>  .../embedded-controller/lenovo,thinkpad-t14s-ec.yaml         | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
> index c87ccb5b3086..0d049979e35b 100644
> --- a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
> +++ b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
> @@ -26,10 +26,14 @@ properties:
>  
>    wakeup-source: true
>  
> +  "#thermal-sensor-cells":
> +    const: 1
> +
>  required:
>    - compatible
>    - reg
>    - interrupts
> +  - "#thermal-sensor-cells"

This looks like ABI break without explanation.

Best regards,
Krzysztof

Re: [PATCH v5 2/3] platform: arm64: lenovo-thinkpad-t14s-ec: Add hwmon support for temperatures

[Krzysztof Kozlowski]

On Mon, Jul 06, 2026 at 08:46:47PM +0200, Daniel Lezcano wrote:
> +static int t14s_ec_hwmon_probe(struct t14s_ec *ec)
> +{
> +	struct device *dev;
> +	struct t14s_ec_hwmon_sys_thermx sys_thermx[] = {
> +		{ .label = "soc",	.reg = T14S_EC_SYS_THERM0 },
> +		{ .label = "keyboard",	.reg = T14S_EC_SYS_THERM1 },
> +		{ .label = "base",	.reg = T14S_EC_SYS_THERM2 },
> +		{ .label = "charging",	.reg = T14S_EC_SYS_THERM3 },
> +		{ .label = "qtm",	.reg = T14S_EC_SYS_THERM6 },
> +		{ .label = "ssd",	.reg = T14S_EC_SYS_THERM7 },
> +	};
> +
> +	ec->ec_hwmon.sys_thermx = devm_kmemdup_array(ec->dev, sys_thermx,
> +						     ARRAY_SIZE(sys_thermx),
> +						     sizeof(sys_thermx[0]), GFP_KERNEL);
> +	if (!ec->ec_hwmon.sys_thermx)
> +		return -ENOMEM;
> +
> +	dev = devm_hwmon_device_register_with_info(ec->dev, "t14s_ec", ec,
> +						   &t14s_ec_chip_info, NULL);
> +
> +	return PTR_ERR_OR_ZERO(dev);

... and this ...

> +}
> +
>  static int t14s_ec_probe(struct i2c_client *client)
>  {
>  	struct device *dev = &client->dev;
> @@ -590,6 +717,10 @@ static int t14s_ec_probe(struct i2c_client *client)
>  	if (ret < 0)
>  		return ret;
>  
> +	ret = t14s_ec_hwmon_probe(ec);
> +	if (ret < 0)
> +		return ret;

... and this is actual implemented ABI break, if I understood hwmon and
thermal code correctly.

> +
>  	ret = devm_request_threaded_irq(dev, client->irq, NULL,
>  					t14s_ec_irq_handler,
>  					IRQF_ONESHOT, dev_name(dev), ec);

Best regards,
Krzysztof

Re: [PATCH v5 1/3] dt-bindings: embedded-controller: Add Lenovo ThinkPad T14s thermal sensor provider support

[Daniel Lezcano]

On 7/7/26 08:38, Krzysztof Kozlowski wrote:
> On Mon, Jul 06, 2026 at 08:46:46PM +0200, Daniel Lezcano wrote:
>> Document the Lenovo ThinkPad T14s Embedded Controller as a thermal
>> sensor provider by adding the '#thermal-sensor-cells' property.
>>
>> This allows the EC temperature sensors to be referenced from thermal
>> zones in the device tree.
>>
>> Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
>> ---
>>   .../embedded-controller/lenovo,thinkpad-t14s-ec.yaml         | 5 +++++
>>   1 file changed, 5 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
>> index c87ccb5b3086..0d049979e35b 100644
>> --- a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
>> +++ b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
>> @@ -26,10 +26,14 @@ properties:
>>   
>>     wakeup-source: true
>>   
>> +  "#thermal-sensor-cells":
>> +    const: 1
>> +
>>   required:
>>     - compatible
>>     - reg
>>     - interrupts
>> +  - "#thermal-sensor-cells"
> 
> This looks like ABI break without explanation.

What would you suggest ? explanation or removed from required properties?

Re: [PATCH v5 1/3] dt-bindings: embedded-controller: Add Lenovo ThinkPad T14s thermal sensor provider support

[Krzysztof Kozlowski]

On 07/07/2026 10:08, Daniel Lezcano wrote:
> On 7/7/26 08:38, Krzysztof Kozlowski wrote:
>> On Mon, Jul 06, 2026 at 08:46:46PM +0200, Daniel Lezcano wrote:
>>> Document the Lenovo ThinkPad T14s Embedded Controller as a thermal
>>> sensor provider by adding the '#thermal-sensor-cells' property.
>>>
>>> This allows the EC temperature sensors to be referenced from thermal
>>> zones in the device tree.
>>>
>>> Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
>>> ---
>>>   .../embedded-controller/lenovo,thinkpad-t14s-ec.yaml         | 5 +++++
>>>   1 file changed, 5 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
>>> index c87ccb5b3086..0d049979e35b 100644
>>> --- a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
>>> +++ b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
>>> @@ -26,10 +26,14 @@ properties:
>>>   
>>>     wakeup-source: true
>>>   
>>> +  "#thermal-sensor-cells":
>>> +    const: 1
>>> +
>>>   required:
>>>     - compatible
>>>     - reg
>>>     - interrupts
>>> +  - "#thermal-sensor-cells"
>>
>> This looks like ABI break without explanation.
> 
> What would you suggest ? explanation or removed from required properties?

I don't know what is the explanation. If this is actual ABI break as I
read Linux code, what is the rationale behind breaking real users?

Best regards,
Krzysztof

Re: [PATCH v5 1/3] dt-bindings: embedded-controller: Add Lenovo ThinkPad T14s thermal sensor provider support

[Daniel Lezcano]

On 7/7/26 10:09, Krzysztof Kozlowski wrote:
> On 07/07/2026 10:08, Daniel Lezcano wrote:
>> On 7/7/26 08:38, Krzysztof Kozlowski wrote:
>>> On Mon, Jul 06, 2026 at 08:46:46PM +0200, Daniel Lezcano wrote:
>>>> Document the Lenovo ThinkPad T14s Embedded Controller as a thermal
>>>> sensor provider by adding the '#thermal-sensor-cells' property.
>>>>
>>>> This allows the EC temperature sensors to be referenced from thermal
>>>> zones in the device tree.
>>>>
>>>> Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
>>>> ---
>>>>    .../embedded-controller/lenovo,thinkpad-t14s-ec.yaml         | 5 +++++
>>>>    1 file changed, 5 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
>>>> index c87ccb5b3086..0d049979e35b 100644
>>>> --- a/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
>>>> +++ b/Documentation/devicetree/bindings/embedded-controller/lenovo,thinkpad-t14s-ec.yaml
>>>> @@ -26,10 +26,14 @@ properties:
>>>>    
>>>>      wakeup-source: true
>>>>    
>>>> +  "#thermal-sensor-cells":
>>>> +    const: 1
>>>> +
>>>>    required:
>>>>      - compatible
>>>>      - reg
>>>>      - interrupts
>>>> +  - "#thermal-sensor-cells"
>>>
>>> This looks like ABI break without explanation.
>>
>> What would you suggest ? explanation or removed from required properties?
> 
> I don't know what is the explanation. If this is actual ABI break as I
> read Linux code, what is the rationale behind breaking real users?

IIUC, if the DT has not #thermal-sensor-cells, but the code has the 
patch 2/3 then the hwmon fails to initialize as well as the EC 
controller, right ?