[PATCH v3 0/6] hwmon: (lm63) Add Sensylink CTF2301 support

[PATCH v3 0/6] hwmon: (lm63) Add Sensylink CTF2301 support

[Troy Mitchell]

Sensylink CTF2301 is a system-level thermal management solution chip.

The CTF2301 is an I2C/SMBus compatible device featuring:
  - One local temperature sensor with +/-0.5 degree C accuracy and
    0.0625 degree C resolution.
  - One remote temperature sensor for external diode-connected
    transistors, offering +/-1 degree C accuracy and 0.125 degree C
    resolution (temperature range: -40 degree C to +125 degree C).
  - An integrated PWM fan controller capable of operating in two modes:
      1. Direct-DCY: Open-loop direct duty cycle control.
      2. Auto-Temp: Closed-loop automatic fan speed control based on
         measured temperature.
  - A 1-channel fan speed monitor (TACH input) for RPM measurement.

As Guenter pointed out on v1, the CTF2301 register map is a near match
for the LM63/LM96163 family (local and remote temperature, tachometer and
PWM fan control), so this version drops the standalone ctf2301 driver
and instead adds CTF2301 as a new chip type in the existing lm63 driver.
This reuses the shared temperature, limit, alarm and PWM handling instead
of duplicating it.

The CTF2301-specific differences are handled on top of lm63: 12-bit local
temperature input and high-limit values, nine conversion rates, 12
fan-control lookup table entries, and optional 22.5 kHz high-resolution
PWM. When no IRQ is described, the shared ALERT/TACH pin is configured as
a tachometer input. The LM63 family can also register as a thermal cooling
device when the device tree provides the #cooling-cells property.

The required SpacemiT I2C controller clock series has been merged but is
not yet included in an rc release:
https://lore.kernel.org/all/20260508-k1-i2c-ilcr-v7-0-8c2dde5c3ed5@linux.spacemit.com/

Apply that series before testing this series on K3. Without it, the I2C
controller cannot generate an accurate 400 kHz SCL clock and CTF2301
accesses may fail.

Tested on a SpacemiT K3 CoM260 by booting an initramfs and verifying the
CTF2301 probe. Temperature, tachometer, PWM, and conversion-rate behavior
were checked against direct I2C register accesses and the datasheet.

Datasheet:
https://www.sensylink.com/upload/1/net.sensylink.portal/1689557281035.pdf

Register description:
https://github.com/TroyMitchell911/ctf2301-datasheet

Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
---
Changes in v3:
- Add the Sensylink website link to the vendor-prefix commit.
- Preserve the optional interrupt from the trivial-devices binding.
- Explain in the commit message of patch 3/6 why CTF2301 cannot use
  national,lm63 as a fallback compatible.
- Check both bytes of CTF2301 local temperature values before caching them.
- Use the schema-valid 25 mA drive strength for the K3 I2C6 pins.
- Link to v2: https://patch.msgid.link/20260721-ctl2301-v2-0-ef5fb342872a@linux.dev

Changes in v2:
- Replace the standalone CTF2301 driver with a new lm63 chip type, as
  suggested by Guenter, reusing the existing temperature, limit, alarm,
  tachometer, PWM, and automatic fan-control paths.
- Add the temperature thresholds, alarms, and automatic fan-control lookup
  table support which were missing from the v1 driver.
- Handle CTF2301-specific 12-bit local temperature values, nine conversion
  rates, 12 lookup table entries, shared ALERT/TACH pin, and optional
  22.5 kHz high-resolution PWM.
- Propagate SMBus failures from lm63 initialization and write paths.
- Add optional thermal cooling-device support for the LM63 family using
  the existing manual PWM control path.
- Move the National LM63-family compatibles from trivial-devices.yaml to a
  dedicated binding which permits #cooling-cells.
- Add CTF2301 to the LM63-family binding instead of keeping the standalone
  schema from v1. Do not declare #cooling-cells on K3 CoM260 yet because
  the board has no thermal consumer.
- Fix the binding errors reported by Rob by using a plain compatible string
  and wrapping the description.
- Document CTF2301 support in the lm63 hwmon documentation and provide the
  detailed register description used for review.
- Add the K3 CoM260 I2C6 pinctrl state and CTF2301 device node for hardware
  testing.
- Link to v1: https://lore.kernel.org/r/20250916-ctl2301-v1-0-97e7c84f2c47@linux.dev

To: Rob Herring <robh@kernel.org>
To: Krzysztof Kozlowski <krzk+dt@kernel.org>
To: Conor Dooley <conor+dt@kernel.org>
To: Guenter Roeck <linux@roeck-us.net>
To: Paul Walmsley <pjw@kernel.org>
To: Palmer Dabbelt <palmer@dabbelt.com>
To: Albert Ou <aou@eecs.berkeley.edu>
To: Alexandre Ghiti <alex@ghiti.fr>
To: Yixun Lan <dlan@kernel.org>
To: Jonathan Corbet <corbet@lwn.net>
To: Shuah Khan <skhan@linuxfoundation.org>
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-hwmon@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Cc: spacemit@lists.linux.dev
Cc: linux-doc@vger.kernel.org

---
Troy Mitchell (6):
      dt-bindings: vendor-prefixes: Add Sensylink
      dt-bindings: hwmon: Move LM63 family to a dedicated binding
      dt-bindings: hwmon: Add Sensylink CTF2301
      hwmon: (lm63) Add Sensylink CTF2301 support
      riscv: dts: spacemit: Add K3 I2C6 pinctrl state
      riscv: dts: spacemit: Add CTF2301 on K3 CoM260

 .../devicetree/bindings/hwmon/national,lm63.yaml   |  55 +++
 .../devicetree/bindings/trivial-devices.yaml       |   6 -
 .../devicetree/bindings/vendor-prefixes.yaml       |   2 +
 Documentation/hwmon/lm63.rst                       |  22 ++
 arch/riscv/boot/dts/spacemit/k3-com260.dtsi        |  19 +
 arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi       |  11 +
 drivers/hwmon/Kconfig                              |   8 +-
 drivers/hwmon/lm63.c                               | 414 +++++++++++++++++----
 8 files changed, 453 insertions(+), 84 deletions(-)
---
base-commit: a13c140cc289c0b7b3770bce5b3ad42ab35074aa
change-id: 20250916-ctl2301-0416b073c280

Best regards,
--  
Troy Mitchell <troy.mitchell@linux.dev>

[PATCH v3 1/6] dt-bindings: vendor-prefixes: Add Sensylink

[Troy Mitchell]

Add the vendor prefix for Sensylink Microelectronics.

Link: https://en.sensylink.com/
Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 396044f368e7..22d0d26f1bbd 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -1467,6 +1467,8 @@ patternProperties:
     description: Sensirion AG
   "^sensortek,.*":
     description: Sensortek Technology Corporation
+  "^sensylink,.*":
+    description: Sensylink Microelectronics Technology Co., Ltd.
   "^sercomm,.*":
     description: Sercomm (Suzhou) Corporation
   "^sff,.*":

-- 
2.55.0

Re: [PATCH v3 1/6] dt-bindings: vendor-prefixes: Add Sensylink

[sashiko-bot]

> Add the vendor prefix for Sensylink Microelectronics.
> 
> Link: https://en.sensylink.com/
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-ctl2301-v3-0-fd4b8ffb5b0d@linux.dev?part=1

Re: [PATCH v3 1/6] dt-bindings: vendor-prefixes: Add Sensylink

[Krzysztof Kozlowski]

On Wed, Aug 05, 2026 at 02:00:51AM -0700, Troy Mitchell wrote:
> Add the vendor prefix for Sensylink Microelectronics.
> 
> Link: https://en.sensylink.com/
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
> ---
>  Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
>  1 file changed, 2 insertions(+)

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof

[PATCH v3 2/6] dt-bindings: hwmon: Move LM63 family to a dedicated binding

[Troy Mitchell]

Move the National Semiconductor LM63, LM64, and LM96163 compatibles out
of trivial-devices.yaml and into a dedicated binding. Describe their
integrated fan control and preserve the optional interrupt used by the
ALERT output. Permit use as thermal cooling devices via #cooling-cells.

Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
---
 .../devicetree/bindings/hwmon/national,lm63.yaml   | 53 ++++++++++++++++++++++
 .../devicetree/bindings/trivial-devices.yaml       |  6 ---
 2 files changed, 53 insertions(+), 6 deletions(-)

diff --git a/Documentation/devicetree/bindings/hwmon/national,lm63.yaml b/Documentation/devicetree/bindings/hwmon/national,lm63.yaml
new file mode 100644
index 000000000000..f2e0993cfbef
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/national,lm63.yaml
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwmon/national,lm63.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: LM63-compatible temperature sensors with integrated fan control
+
+maintainers:
+  - Guenter Roeck <linux@roeck-us.net>
+
+description: |
+  The LM63 family provides local and remote temperature monitoring together
+  with fan speed monitoring and PWM fan control. Supported devices include
+  the National Semiconductor LM63, LM64 and LM96163.
+
+allOf:
+  - $ref: hwmon-common.yaml#
+
+properties:
+  compatible:
+    enum:
+      - national,lm63
+      - national,lm64
+      - national,lm96163
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  "#cooling-cells":
+    const: 2
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        temperature-sensor@4c {
+            compatible = "national,lm63";
+            reg = <0x4c>;
+            #cooling-cells = <2>;
+        };
+    };
diff --git a/Documentation/devicetree/bindings/trivial-devices.yaml b/Documentation/devicetree/bindings/trivial-devices.yaml
index 435c4baab436..aa62d245464c 100644
--- a/Documentation/devicetree/bindings/trivial-devices.yaml
+++ b/Documentation/devicetree/bindings/trivial-devices.yaml
@@ -364,16 +364,10 @@ properties:
           - mps,mp9945
             # Murata D1U74T-W power supply unit
           - murata,d1u74t
-            # Temperature sensor with integrated fan control
-          - national,lm63
-            # Temperature sensor with integrated fan control
-          - national,lm64
             # Temperature sensor
           - national,lm95235
             # Temperature sensor
           - national,lm95245
-            # Temperature sensor with integrated fan control
-          - national,lm96163
             # Serial Interface ACPI-Compatible Microprocessor System Hardware Monitor
           - national,lm80
             # Serial Interface ACPI-Compatible Microprocessor System Hardware Monitor

-- 
2.55.0

Re: [PATCH v3 2/6] dt-bindings: hwmon: Move LM63 family to a dedicated binding

[sashiko-bot]

> Move the National Semiconductor LM63, LM64, and LM96163 compatibles out
> of trivial-devices.yaml and into a dedicated binding. Describe their
> integrated fan control and preserve the optional interrupt used by the
> ALERT output. Permit use as thermal cooling devices via #cooling-cells.
> 
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-ctl2301-v3-0-fd4b8ffb5b0d@linux.dev?part=2

Re: [PATCH v3 2/6] dt-bindings: hwmon: Move LM63 family to a dedicated binding

[Krzysztof Kozlowski]

On Wed, Aug 05, 2026 at 02:00:52AM -0700, Troy Mitchell wrote:
> Move the National Semiconductor LM63, LM64, and LM96163 compatibles out
> of trivial-devices.yaml and into a dedicated binding. Describe their
> integrated fan control and preserve the optional interrupt used by the
> ALERT output. Permit use as thermal cooling devices via #cooling-cells.
> 
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
> ---
>  .../devicetree/bindings/hwmon/national,lm63.yaml   | 53 ++++++++++++++++++++++
>  .../devicetree/bindings/trivial-devices.yaml       |  6 ---
>  2 files changed, 53 insertions(+), 6 deletions(-)

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof

[PATCH v3 3/6] dt-bindings: hwmon: Add Sensylink CTF2301

[Troy Mitchell]

Add the Sensylink CTF2301 temperature sensor and fan controller to the
LM63 family binding. The chip follows the LM63 register model and can
provide a thermal cooling device when #cooling-cells is present.

Do not provide a national,lm63 fallback because the CTF2301 is not fully
compatible with LM63. It uses different conversion-rate encodings,
extended local-temperature registers, additional fan lookup table
entries, and device-specific PWM and ALERT/TACH configuration. An older
LM63 driver would therefore not operate the device correctly.

Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
---
 Documentation/devicetree/bindings/hwmon/national,lm63.yaml | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/hwmon/national,lm63.yaml b/Documentation/devicetree/bindings/hwmon/national,lm63.yaml
index f2e0993cfbef..4c8d0a15fbd1 100644
--- a/Documentation/devicetree/bindings/hwmon/national,lm63.yaml
+++ b/Documentation/devicetree/bindings/hwmon/national,lm63.yaml
@@ -12,7 +12,8 @@ maintainers:
 description: |
   The LM63 family provides local and remote temperature monitoring together
   with fan speed monitoring and PWM fan control. Supported devices include
-  the National Semiconductor LM63, LM64 and LM96163.
+  the National Semiconductor LM63, LM64 and LM96163, and the Sensylink
+  CTF2301.
 
 allOf:
   - $ref: hwmon-common.yaml#
@@ -23,6 +24,7 @@ properties:
       - national,lm63
       - national,lm64
       - national,lm96163
+      - sensylink,ctf2301
 
   reg:
     maxItems: 1

-- 
2.55.0

Re: [PATCH v3 3/6] dt-bindings: hwmon: Add Sensylink CTF2301

[sashiko-bot]

> Add the Sensylink CTF2301 temperature sensor and fan controller to the
> LM63 family binding. The chip follows the LM63 register model and can
> provide a thermal cooling device when #cooling-cells is present.
> 
> Do not provide a national,lm63 fallback because the CTF2301 is not fully
> compatible with LM63. It uses different conversion-rate encodings,
> extended local-temperature registers, additional fan lookup table
> entries, and device-specific PWM and ALERT/TACH configuration. An older
> LM63 driver would therefore not operate the device correctly.
> 
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-ctl2301-v3-0-fd4b8ffb5b0d@linux.dev?part=3

Re: [PATCH v3 3/6] dt-bindings: hwmon: Add Sensylink CTF2301

[Krzysztof Kozlowski]

On Wed, Aug 05, 2026 at 02:00:53AM -0700, Troy Mitchell wrote:
> Add the Sensylink CTF2301 temperature sensor and fan controller to the
> LM63 family binding. The chip follows the LM63 register model and can
> provide a thermal cooling device when #cooling-cells is present.
> 
> Do not provide a national,lm63 fallback because the CTF2301 is not fully
> compatible with LM63. It uses different conversion-rate encodings,
> extended local-temperature registers, additional fan lookup table
> entries, and device-specific PWM and ALERT/TACH configuration. An older
> LM63 driver would therefore not operate the device correctly.
> 
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
> ---
>  Documentation/devicetree/bindings/hwmon/national,lm63.yaml | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof

[PATCH v3 4/6] hwmon: (lm63) Add Sensylink CTF2301 support

[Troy Mitchell]

Add Sensylink CTF2301 support to the LM63 driver. CTF2301 follows
the LM63-style temperature, tachometer, and PWM register layout,
while using a 12-bit local temperature register and requiring the
ALERT/TACH pin to be configured for tachometer input.

Register an optional thermal cooling device when the device tree
node provides #cooling-cells, allowing thermal zones to control
the fan through the existing PWM path without changing behavior
for existing LM63-family users.

Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
---
 Documentation/hwmon/lm63.rst |  22 +++
 drivers/hwmon/Kconfig        |   8 +-
 drivers/hwmon/lm63.c         | 414 +++++++++++++++++++++++++++++++++++--------
 3 files changed, 366 insertions(+), 78 deletions(-)

diff --git a/Documentation/hwmon/lm63.rst b/Documentation/hwmon/lm63.rst
index 9e27367d7405..c40bd0dfe591 100644
--- a/Documentation/hwmon/lm63.rst
+++ b/Documentation/hwmon/lm63.rst
@@ -33,6 +33,16 @@ Supported chips:
 
 	       http://www.national.com/pf/LM/LM96163.html
 
+  * Sensylink CTF2301
+
+    Prefix: 'ctf2301'
+
+    Addresses scanned: none
+
+    Datasheet: https://www.sensylink.com/upload/1/net.sensylink.portal/1689557281035.pdf
+
+    Register description: https://github.com/TroyMitchell911/ctf2301-datasheet
+
 
 Author: Jean Delvare <jdelvare@suse.de>
 
@@ -62,6 +72,8 @@ value have to be masked out. The value is still 16 bit in width.
 
 All temperature values are given in degrees Celsius. Resolution is 1.0
 degree for the local temperature, 0.125 degree for the remote temperature.
+The CTF2301 local temperature input and limit have a resolution of 0.0625
+degree.
 
 The fan speed is measured using a tachometer. Contrary to most chips which
 store the value in an 8-bit register and have a selectable clock divider
@@ -93,3 +105,13 @@ support these GPIO lines at present.
 The LM96163 is an enhanced version of LM63 with improved temperature accuracy
 and better PWM resolution. For LM96163, the external temperature sensor type is
 configurable as CPU embedded diode(1) or 3904 transistor(2).
+
+The CTF2301 is register-compatible with the LM63 family and provides 12 fan
+control lookup table entries. It supports 8-bit PWM resolution when configured
+for a 22.5 kHz PWM frequency.
+
+Device tree nodes may declare ``#cooling-cells`` to register the fan controller
+with the thermal framework. The cooling state is mapped to the existing
+``pwm1`` range from 0 to 255. The driver keeps the current automatic or manual
+fan control mode during probe and switches to manual control when the thermal
+framework first requests a cooling state.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 2bfbcc033d59..abb1af8664fb 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1501,10 +1501,10 @@ config SENSORS_LM63
 	depends on I2C
 	help
 	  If you say yes here you get support for the National
-	  Semiconductor LM63, LM64, and LM96163 remote diode digital temperature
-	  sensors with integrated fan control.  Such chips are found
-	  on the Tyan S4882 (Thunder K8QS Pro) motherboard, among
-	  others.
+	  Semiconductor LM63, LM64, LM96163, and Sensylink CTF2301
+	  remote diode digital temperature sensors with integrated fan
+	  control. Such chips are found on the Tyan S4882 (Thunder K8QS
+	  Pro) motherboard, among others.
 
 	  This driver can also be built as a module. If so, the module
 	  will be called lm63.
diff --git a/drivers/hwmon/lm63.c b/drivers/hwmon/lm63.c
index e2a429e579ac..3887f02b924d 100644
--- a/drivers/hwmon/lm63.c
+++ b/drivers/hwmon/lm63.c
@@ -35,13 +35,14 @@
 #include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/sysfs.h>
+#include <linux/thermal.h>
 #include <linux/types.h>
 
 /*
  * Addresses to scan
  * Address is fully defined internally and cannot be changed except for
  * LM64 which has one pin dedicated to address selection.
- * LM63 and LM96163 have address 0x4c.
+ * LM63, LM96163, and CTF2301 have address 0x4c.
  * LM64 can have address 0x18 or 0x4e.
  */
 
@@ -70,6 +71,9 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END };
 #define LM63_REG_LOCAL_TEMP		0x00
 #define LM63_REG_LOCAL_HIGH		0x05
 
+#define CTF2301_REG_LOCAL_TEMP_LSB	0x15
+#define CTF2301_REG_LOCAL_HIGH_LSB	0x06
+
 #define LM63_REG_REMOTE_TEMP_MSB	0x01
 #define LM63_REG_REMOTE_TEMP_LSB	0x10
 #define LM63_REG_REMOTE_OFFSET_MSB	0x11
@@ -94,6 +98,7 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END };
 
 #define LM63_PWM_BASE_FAST_HZ		180000
 #define LM63_PWM_BASE_SLOW_HZ		700
+#define LM63_MAX_PWM			255
 
 #define LM63_MAX_CONVRATE		9
 
@@ -121,6 +126,9 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END };
 							    127000), 1000)
 #define TEMP8U_TO_REG(val)	DIV_ROUND_CLOSEST(clamp_val((val), 0, \
 							    255000), 1000)
+#define TEMP12_FROM_REG(reg)	DIV_ROUND_CLOSEST((s16)(reg) * 1000, 256)
+#define TEMP12_TO_REG(val)	DIV_ROUND_CLOSEST(clamp_val((val), -128000, \
+							     127937) * 256, 1000)
 #define TEMP11_FROM_REG(reg)	((reg) / 32 * 125)
 #define TEMP11_TO_REG(val)	(DIV_ROUND_CLOSEST(clamp_val((val), -128000, \
 							     127875), 125) * 32)
@@ -132,7 +140,11 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END };
 #define UPDATE_INTERVAL(max, rate) \
 			((1000 << (LM63_MAX_CONVRATE - (rate))) / (max))
 
-enum chips { lm63, lm64, lm96163 };
+enum chips { lm63, lm64, lm96163, ctf2301 };
+
+static const unsigned int ctf2301_update_intervals[] = {
+	20000, 10000, 4902, 2463, 1000, 615, 307, 154, 107
+};
 
 /*
  * Client data (each client gets its own)
@@ -164,6 +176,8 @@ struct lm63_data {
 			   1: local high limit
 			   2: remote critical limit
 			   3-14: lookup table */
+	s16 temp1_input; /* local input for chips with extended resolution */
+	s16 temp1_max; /* local limit for chips with extended resolution */
 	s16 temp11[4];	/* 0: remote input
 			   1: remote low limit
 			   2: remote high limit
@@ -229,6 +243,7 @@ static struct lm63_data *lm63_update_device(struct device *dev)
 	struct lm63_data *data = dev_get_drvdata(dev);
 	struct i2c_client *client = data->client;
 	unsigned long next_update;
+	int msb, lsb;
 
 	mutex_lock(&data->update_lock);
 
@@ -254,10 +269,30 @@ static struct lm63_data *lm63_update_device(struct device *dev)
 		data->pwm1[0] = i2c_smbus_read_byte_data(client,
 				LM63_REG_PWM_VALUE);
 
-		data->temp8[0] = i2c_smbus_read_byte_data(client,
-				 LM63_REG_LOCAL_TEMP);
-		data->temp8[1] = i2c_smbus_read_byte_data(client,
-				 LM63_REG_LOCAL_HIGH);
+		if (data->kind == ctf2301) {
+			msb = i2c_smbus_read_byte_data(client,
+						       LM63_REG_LOCAL_TEMP);
+			lsb = i2c_smbus_read_byte_data(client,
+						       CTF2301_REG_LOCAL_TEMP_LSB);
+			if (msb >= 0 && lsb >= 0) {
+				data->temp8[0] = msb;
+				data->temp1_input = ((u16)(u8)msb << 8) | lsb;
+			}
+
+			msb = i2c_smbus_read_byte_data(client,
+						       LM63_REG_LOCAL_HIGH);
+			lsb = i2c_smbus_read_byte_data(client,
+						       CTF2301_REG_LOCAL_HIGH_LSB);
+			if (msb >= 0 && lsb >= 0) {
+				data->temp8[1] = msb;
+				data->temp1_max = ((u16)(u8)msb << 8) | lsb;
+			}
+		} else {
+			data->temp8[0] = i2c_smbus_read_byte_data(client,
+								  LM63_REG_LOCAL_TEMP);
+			data->temp8[1] = i2c_smbus_read_byte_data(client,
+								  LM63_REG_LOCAL_HIGH);
+		}
 
 		/* order matters for temp2_input */
 		data->temp11[0] = i2c_smbus_read_byte_data(client,
@@ -277,7 +312,7 @@ static struct lm63_data *lm63_update_device(struct device *dev)
 				| i2c_smbus_read_byte_data(client,
 				  LM63_REG_REMOTE_OFFSET_LSB);
 
-		if (data->kind == lm96163)
+		if (data->kind == lm96163 || data->kind == ctf2301)
 			data->temp11u = (i2c_smbus_read_byte_data(client,
 					LM96163_REG_REMOTE_TEMP_U_MSB) << 8)
 				      | i2c_smbus_read_byte_data(client,
@@ -367,6 +402,41 @@ static ssize_t set_fan(struct device *dev, struct device_attribute *dummy,
 	return count;
 }
 
+static int lm63_pwm_from_reg(struct lm63_data *data, u8 reg)
+{
+	if (data->pwm_highres)
+		return reg;
+
+	return reg >= 2 * data->pwm1_freq ?
+	       LM63_MAX_PWM :
+	       (reg * LM63_MAX_PWM + data->pwm1_freq) / (2 * data->pwm1_freq);
+}
+
+static u8 lm63_pwm_to_reg(struct lm63_data *data, unsigned long val)
+{
+	val = clamp_val(val, 0, LM63_MAX_PWM);
+
+	if (data->pwm_highres)
+		return val;
+
+	return (val * data->pwm1_freq * 2 + LM63_MAX_PWM / 2) / LM63_MAX_PWM;
+}
+
+static int lm63_write_pwm(struct lm63_data *data, int nr, unsigned long val)
+{
+	struct i2c_client *client = data->client;
+	u8 reg = nr ? LM63_REG_LUT_PWM(nr - 1) : LM63_REG_PWM_VALUE;
+	u8 regval = lm63_pwm_to_reg(data, val);
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(client, reg, regval);
+	if (ret)
+		return ret;
+	data->pwm1[nr] = regval;
+
+	return 0;
+}
+
 static ssize_t show_pwm1(struct device *dev, struct device_attribute *devattr,
 			 char *buf)
 {
@@ -376,12 +446,7 @@ static ssize_t show_pwm1(struct device *dev, struct device_attribute *devattr,
 	int pwm;
 
 	mutex_lock(&data->update_lock);
-	if (data->pwm_highres)
-		pwm = data->pwm1[nr];
-	else
-		pwm = data->pwm1[nr] >= 2 * data->pwm1_freq ?
-		       255 : (data->pwm1[nr] * 255 + data->pwm1_freq) /
-		       (2 * data->pwm1_freq);
+	pwm = lm63_pwm_from_reg(data, data->pwm1[nr]);
 	mutex_unlock(&data->update_lock);
 
 	return sprintf(buf, "%d\n", pwm);
@@ -392,11 +457,9 @@ static ssize_t set_pwm1(struct device *dev, struct device_attribute *devattr,
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 	struct lm63_data *data = dev_get_drvdata(dev);
-	struct i2c_client *client = data->client;
 	int nr = attr->index;
 	unsigned long val;
 	int err;
-	u8 reg;
 
 	if (!(data->config_fan & 0x20)) /* register is read-only */
 		return -EPERM;
@@ -405,15 +468,11 @@ static ssize_t set_pwm1(struct device *dev, struct device_attribute *devattr,
 	if (err)
 		return err;
 
-	reg = nr ? LM63_REG_LUT_PWM(nr - 1) : LM63_REG_PWM_VALUE;
-	val = clamp_val(val, 0, 255);
-
 	mutex_lock(&data->update_lock);
-	data->pwm1[nr] = data->pwm_highres ? val :
-			(val * data->pwm1_freq * 2 + 127) / 255;
-	i2c_smbus_write_byte_data(client, reg, data->pwm1[nr]);
+	err = lm63_write_pwm(data, nr, val);
 	mutex_unlock(&data->update_lock);
-	return count;
+
+	return err ? err : count;
 }
 
 static ssize_t pwm1_enable_show(struct device *dev,
@@ -486,7 +545,9 @@ static ssize_t pwm1_freq_store(struct device *dev,
 	struct lm63_data *data = dev_get_drvdata(dev);
 	struct i2c_client *client = data->client;
 	unsigned long val, pfr_fast, pfr_slow, err_fast, err_slow, pfr;
+	u8 config_fan;
 	bool slow_clock;
+	int config_enhanced = 0;
 	int ret;
 
 	ret = kstrtoul(buf, 10, &val);
@@ -512,35 +573,55 @@ static ssize_t pwm1_freq_store(struct device *dev,
 
 	mutex_lock(&data->update_lock);
 	ret = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG_FAN);
-	if (ret < 0) {
-		mutex_unlock(&data->update_lock);
-		return ret;
-	}
-	data->config_fan = ret;
+	if (ret < 0)
+		goto unlock;
+	config_fan = ret;
 
-	if (!(data->config_fan & 0x20)) { /* register is read-only */
-		mutex_unlock(&data->update_lock);
-		return -EPERM;
+	if (!(config_fan & 0x20)) { /* register is read-only */
+		ret = -EPERM;
+		goto unlock;
 	}
 
-	if (data->kind == lm96163) {
-		ret = i2c_smbus_read_byte_data(client, LM96163_REG_CONFIG_ENHANCED);
-		if (ret < 0) {
-			mutex_unlock(&data->update_lock);
-			return ret;
+	if (data->kind == lm96163 || data->kind == ctf2301) {
+		ret = i2c_smbus_read_byte_data(client,
+					       LM96163_REG_CONFIG_ENHANCED);
+		if (ret < 0)
+			goto unlock;
+		config_enhanced = ret;
+
+		if (data->kind == ctf2301) {
+			if (!slow_clock && pfr == 8)
+				config_enhanced |= 0x10;
+			else
+				config_enhanced &= ~0x10;
+			ret = i2c_smbus_write_byte_data(client,
+							LM96163_REG_CONFIG_ENHANCED,
+							config_enhanced);
+			if (ret)
+				goto unlock;
 		}
-		data->pwm_highres = !slow_clock && pfr == 8 && (ret & 0x10);
 	}
 
 	if (slow_clock)
-		data->config_fan |= 0x08;
+		config_fan |= 0x08;
 	else
-		data->config_fan &= ~0x08;
-	i2c_smbus_write_byte_data(client, LM63_REG_CONFIG_FAN, data->config_fan);
-	i2c_smbus_write_byte_data(client, LM63_REG_PWM_FREQ, pfr);
+		config_fan &= ~0x08;
+	ret = i2c_smbus_write_byte_data(client, LM63_REG_PWM_FREQ, pfr);
+	if (ret)
+		goto unlock;
+	ret = i2c_smbus_write_byte_data(client, LM63_REG_CONFIG_FAN,
+					config_fan);
+	if (ret)
+		goto unlock;
+
+	data->config_fan = config_fan;
 	data->pwm1_freq = pfr;
+	data->pwm_highres = !slow_clock && pfr == 8 &&
+				(config_enhanced & 0x10);
+unlock:
 	mutex_unlock(&data->update_lock);
-	return count;
+
+	return ret ? ret : count;
 }
 
 /*
@@ -555,6 +636,11 @@ static ssize_t show_local_temp8(struct device *dev,
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 	struct lm63_data *data = lm63_update_device(dev);
+
+	if (data->kind == ctf2301)
+		return sprintf(buf, "%d\n", TEMP12_FROM_REG(attr->index ?
+				       data->temp1_max : data->temp1_input));
+
 	return sprintf(buf, "%d\n", TEMP8_FROM_REG(data->temp8[attr->index]));
 }
 
@@ -595,6 +681,23 @@ static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
 		return err;
 
 	mutex_lock(&data->update_lock);
+	if (data->kind == ctf2301 && nr == 1) {
+		temp = TEMP12_TO_REG(val);
+		err = i2c_smbus_write_byte_data(client, LM63_REG_LOCAL_HIGH,
+						temp >> 8);
+		if (!err)
+			err = i2c_smbus_write_byte_data(client,
+							CTF2301_REG_LOCAL_HIGH_LSB,
+							temp & 0xf0);
+		if (!err) {
+			data->temp8[nr] = temp >> 8;
+			data->temp1_max = temp;
+		}
+		mutex_unlock(&data->update_lock);
+
+		return err ? err : count;
+	}
+
 	switch (nr) {
 	case 2:
 		reg = LM63_REG_REMOTE_TCRIT;
@@ -611,10 +714,12 @@ static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
 		reg = LM63_REG_LUT_TEMP(nr - 3);
 		temp = lut_temp_to_reg(data, val);
 	}
-	data->temp8[nr] = temp;
-	i2c_smbus_write_byte_data(client, reg, temp);
+	err = i2c_smbus_write_byte_data(client, reg, temp);
+	if (!err)
+		data->temp8[nr] = temp;
 	mutex_unlock(&data->update_lock);
-	return count;
+
+	return err ? err : count;
 }
 
 static ssize_t show_temp11(struct device *dev, struct device_attribute *devattr,
@@ -788,11 +893,40 @@ static ssize_t temp2_crit_hyst_store(struct device *dev,
  * Set conversion rate.
  * client->update_lock must be held when calling this function.
  */
-static void lm63_set_convrate(struct lm63_data *data, unsigned int interval)
+static unsigned int lm63_update_interval(struct lm63_data *data, u8 rate)
+{
+	if (data->kind == ctf2301)
+		return ctf2301_update_intervals[min_t(unsigned int, rate,
+					ARRAY_SIZE(ctf2301_update_intervals) - 1)];
+
+	return UPDATE_INTERVAL(data->max_convrate_hz, rate);
+}
+
+static int lm63_set_convrate(struct lm63_data *data, unsigned int interval)
 {
 	struct i2c_client *client = data->client;
-	unsigned int update_interval;
-	int i;
+	unsigned int update_interval, error, best_error = ~0U;
+	unsigned int best = 0;
+	unsigned int i;
+	int ret;
+
+	if (data->kind == ctf2301) {
+		for (i = 0; i < ARRAY_SIZE(ctf2301_update_intervals); i++) {
+			error = abs_diff(interval, ctf2301_update_intervals[i]);
+			if (error < best_error) {
+				best_error = error;
+				best = i;
+			}
+		}
+
+		ret = i2c_smbus_write_byte_data(client, LM63_REG_CONVRATE,
+						best);
+		if (ret)
+			return ret;
+		data->update_interval = ctf2301_update_intervals[best];
+
+		return 0;
+	}
 
 	/* Shift calculations to avoid rounding errors */
 	interval <<= 6;
@@ -804,8 +938,12 @@ static void lm63_set_convrate(struct lm63_data *data, unsigned int interval)
 		if (interval >= update_interval * 3 / 4)
 			break;
 
-	i2c_smbus_write_byte_data(client, LM63_REG_CONVRATE, i);
+	ret = i2c_smbus_write_byte_data(client, LM63_REG_CONVRATE, i);
+	if (ret)
+		return ret;
 	data->update_interval = UPDATE_INTERVAL(data->max_convrate_hz, i);
+
+	return 0;
 }
 
 static ssize_t update_interval_show(struct device *dev,
@@ -829,10 +967,10 @@ static ssize_t update_interval_store(struct device *dev,
 		return err;
 
 	mutex_lock(&data->update_lock);
-	lm63_set_convrate(data, clamp_val(val, 0, 100000));
+	err = lm63_set_convrate(data, clamp_val(val, 0, 100000));
 	mutex_unlock(&data->update_lock);
 
-	return count;
+	return err ? err : count;
 }
 
 static ssize_t temp2_type_show(struct device *dev,
@@ -997,6 +1135,75 @@ static DEVICE_ATTR_RO(alarms);
 
 static DEVICE_ATTR_RW(update_interval);
 
+static int lm63_get_max_state(struct thermal_cooling_device *cdev,
+			      unsigned long *state)
+{
+	*state = LM63_MAX_PWM;
+
+	return 0;
+}
+
+static int lm63_get_cur_state(struct thermal_cooling_device *cdev,
+			      unsigned long *state)
+{
+	struct lm63_data *data = cdev->devdata;
+	int ret;
+
+	mutex_lock(&data->update_lock);
+	ret = i2c_smbus_read_byte_data(data->client, LM63_REG_PWM_VALUE);
+	if (ret < 0)
+		goto unlock;
+
+	data->pwm1[0] = ret;
+	*state = lm63_pwm_from_reg(data, data->pwm1[0]);
+unlock:
+	mutex_unlock(&data->update_lock);
+
+	return ret < 0 ? ret : 0;
+}
+
+static int lm63_set_cur_state(struct thermal_cooling_device *cdev,
+			      unsigned long state)
+{
+	struct lm63_data *data = cdev->devdata;
+	int config_fan;
+	int ret;
+
+	if (state > LM63_MAX_PWM)
+		return -EINVAL;
+
+	mutex_lock(&data->update_lock);
+	config_fan = i2c_smbus_read_byte_data(data->client,
+					      LM63_REG_CONFIG_FAN);
+	if (config_fan < 0) {
+		ret = config_fan;
+		goto unlock;
+	}
+	data->config_fan = config_fan;
+
+	if (!(config_fan & 0x20)) {
+		config_fan |= 0x20;
+		ret = i2c_smbus_write_byte_data(data->client,
+						LM63_REG_CONFIG_FAN,
+						config_fan);
+		if (ret)
+			goto unlock;
+		data->config_fan = config_fan;
+	}
+
+	ret = lm63_write_pwm(data, 0, state);
+unlock:
+	mutex_unlock(&data->update_lock);
+
+	return ret;
+}
+
+static const struct thermal_cooling_device_ops lm63_cooling_ops = {
+	.get_max_state = lm63_get_max_state,
+	.get_cur_state = lm63_get_cur_state,
+	.set_cur_state = lm63_set_cur_state,
+};
+
 static struct attribute *lm63_attributes[] = {
 	&sensor_dev_attr_pwm1.dev_attr.attr,
 	&dev_attr_pwm1_enable.attr,
@@ -1079,8 +1286,8 @@ static const struct attribute_group lm63_group_extra_lut = {
  * On LM63, temp2_crit can be set only once, which should be job
  * of the bootloader.
  * On LM64, temp2_crit can always be set.
- * On LM96163, temp2_crit can be set if bit 1 of the configuration
- * register is true.
+ * On LM96163 and CTF2301, temp2_crit can be set if bit 1 of the
+ * configuration register is true.
  */
 static umode_t lm63_attribute_mode(struct kobject *kobj,
 				   struct attribute *attr, int index)
@@ -1090,7 +1297,8 @@ static umode_t lm63_attribute_mode(struct kobject *kobj,
 
 	if (attr == &sensor_dev_attr_temp2_crit.dev_attr.attr
 	    && (data->kind == lm64 ||
-		(data->kind == lm96163 && (data->config & 0x02))))
+		((data->kind == lm96163 || data->kind == ctf2301) &&
+		 (data->config & 0x02))))
 		return attr->mode | S_IWUSR;
 
 	return attr->mode;
@@ -1165,29 +1373,48 @@ static int lm63_detect(struct i2c_client *client,
  * Ideally we shouldn't have to initialize anything, since the BIOS
  * should have taken care of everything
  */
-static void lm63_init_client(struct lm63_data *data)
+static int lm63_init_client(struct lm63_data *data)
 {
 	struct i2c_client *client = data->client;
 	struct device *dev = &client->dev;
 	u8 convrate;
+	int ret;
 
-	data->config = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG1);
-	data->config_fan = i2c_smbus_read_byte_data(client,
-						    LM63_REG_CONFIG_FAN);
+	ret = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG1);
+	if (ret < 0)
+		return ret;
+	data->config = ret;
+	ret = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG_FAN);
+	if (ret < 0)
+		return ret;
+	data->config_fan = ret;
 
 	/* Start converting if needed */
 	if (data->config & 0x40) { /* standby */
 		dev_dbg(dev, "Switching to operational mode\n");
 		data->config &= 0xA7;
-		i2c_smbus_write_byte_data(client, LM63_REG_CONFIG1,
-					  data->config);
+		ret = i2c_smbus_write_byte_data(client, LM63_REG_CONFIG1,
+						data->config);
+		if (ret)
+			return ret;
 	}
 	/* Tachometer is always enabled on LM64 */
 	if (data->kind == lm64)
 		data->config |= 0x04;
+	if (data->kind == ctf2301 && !client->irq && !(data->config & 0x04)) {
+		dev_dbg(dev, "Configuring ALERT/TACH pin for tachometer input\n");
+		data->config |= 0x04;
+		ret = i2c_smbus_write_byte_data(client, LM63_REG_CONFIG1,
+						data->config);
+		if (ret)
+			return ret;
+	}
 
 	/* We may need pwm1_freq before ever updating the client data */
-	data->pwm1_freq = i2c_smbus_read_byte_data(client, LM63_REG_PWM_FREQ);
+	ret = i2c_smbus_read_byte_data(client, LM63_REG_PWM_FREQ);
+	if (ret < 0)
+		return ret;
+	data->pwm1_freq = ret;
 	if (data->pwm1_freq == 0)
 		data->pwm1_freq = 1;
 
@@ -1200,25 +1427,38 @@ static void lm63_init_client(struct lm63_data *data)
 	case lm96163:
 		data->max_convrate_hz = LM96163_MAX_CONVRATE_HZ;
 		data->lut_size = 12;
-		data->trutherm
-		  = i2c_smbus_read_byte_data(client,
-					     LM96163_REG_TRUTHERM) & 0x02;
+		ret = i2c_smbus_read_byte_data(client, LM96163_REG_TRUTHERM);
+		if (ret < 0)
+			return ret;
+		data->trutherm = ret & 0x02;
+		break;
+	case ctf2301:
+		data->lut_size = 12;
 		break;
 	}
-	convrate = i2c_smbus_read_byte_data(client, LM63_REG_CONVRATE);
-	if (unlikely(convrate > LM63_MAX_CONVRATE))
+	ret = i2c_smbus_read_byte_data(client, LM63_REG_CONVRATE);
+	if (ret < 0)
+		return ret;
+	convrate = ret;
+	if (data->kind == ctf2301 &&
+	    convrate >= ARRAY_SIZE(ctf2301_update_intervals))
+		convrate = ARRAY_SIZE(ctf2301_update_intervals) - 1;
+	else if (unlikely(convrate > LM63_MAX_CONVRATE))
 		convrate = LM63_MAX_CONVRATE;
-	data->update_interval = UPDATE_INTERVAL(data->max_convrate_hz,
-						convrate);
+	data->update_interval = lm63_update_interval(data, convrate);
 
 	/*
-	 * For LM96163, check if high resolution PWM
+	 * For LM96163 and CTF2301, check if high resolution PWM
 	 * and unsigned temperature format is enabled.
 	 */
-	if (data->kind == lm96163) {
-		u8 config_enhanced
-		  = i2c_smbus_read_byte_data(client,
-					     LM96163_REG_CONFIG_ENHANCED);
+	if (data->kind == lm96163 || data->kind == ctf2301) {
+		u8 config_enhanced;
+
+		ret = i2c_smbus_read_byte_data(client,
+					       LM96163_REG_CONFIG_ENHANCED);
+		if (ret < 0)
+			return ret;
+		config_enhanced = ret;
 		if (config_enhanced & 0x20)
 			data->lut_temp_highres = true;
 		if ((config_enhanced & 0x10)
@@ -1239,6 +1479,8 @@ static void lm63_init_client(struct lm63_data *data)
 	dev_dbg(dev, "PWM output active %s, %s mode\n",
 		(data->config_fan & 0x10) ? "low" : "high",
 		(data->config_fan & 0x20) ? "manual" : "auto");
+
+	return 0;
 }
 
 static const struct i2c_device_id lm63_id[];
@@ -1246,9 +1488,11 @@ static const struct i2c_device_id lm63_id[];
 static int lm63_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
+	struct thermal_cooling_device *cdev;
 	struct device *hwmon_dev;
 	struct lm63_data *data;
 	int groups = 0;
+	int ret;
 
 	data = devm_kzalloc(dev, sizeof(struct lm63_data), GFP_KERNEL);
 	if (!data)
@@ -1263,7 +1507,9 @@ static int lm63_probe(struct i2c_client *client)
 		data->temp2_offset = 16000;
 
 	/* Initialize chip */
-	lm63_init_client(data);
+	ret = lm63_init_client(data);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to initialize device\n");
 
 	/* Register sysfs hooks */
 	data->groups[groups++] = &lm63_group;
@@ -1273,11 +1519,26 @@ static int lm63_probe(struct i2c_client *client)
 	if (data->kind == lm96163) {
 		data->groups[groups++] = &lm63_group_temp2_type;
 		data->groups[groups++] = &lm63_group_extra_lut;
+	} else if (data->kind == ctf2301) {
+		data->groups[groups++] = &lm63_group_extra_lut;
 	}
 
 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 							   data, data->groups);
-	return PTR_ERR_OR_ZERO(hwmon_dev);
+	if (IS_ERR(hwmon_dev))
+		return PTR_ERR(hwmon_dev);
+
+	if (IS_ENABLED(CONFIG_THERMAL_OF) &&
+	    of_property_present(dev->of_node, "#cooling-cells")) {
+		cdev = devm_thermal_of_cooling_device_register(dev, 0,
+							       client->name,
+							       data,
+							       &lm63_cooling_ops);
+		if (IS_ERR(cdev))
+			return PTR_ERR(cdev);
+	}
+
+	return 0;
 }
 
 /*
@@ -1288,6 +1549,7 @@ static const struct i2c_device_id lm63_id[] = {
 	{ .name = "lm63", .driver_data = lm63 },
 	{ .name = "lm64", .driver_data = lm64 },
 	{ .name = "lm96163", .driver_data = lm96163 },
+	{ .name = "ctf2301", .driver_data = ctf2301 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, lm63_id);
@@ -1305,6 +1567,10 @@ static const struct of_device_id __maybe_unused lm63_of_match[] = {
 		.compatible = "national,lm96163",
 		.data = (void *)lm96163
 	},
+	{
+		.compatible = "sensylink,ctf2301",
+		.data = (void *)ctf2301
+	},
 	{ },
 };
 MODULE_DEVICE_TABLE(of, lm63_of_match);

-- 
2.55.0

Re: [PATCH v3 4/6] hwmon: (lm63) Add Sensylink CTF2301 support

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:
- [High] Missing Kconfig dependency causes undefined reference to devm_thermal_of_cooling_device_register.
- [Medium] Missing lock around 16-bit variable read in show_local_temp8.
- [Medium] Handling of I2C write errors in pwm1_freq_store permanently desynchronizes the driver's software state from the hardware state.
--

--- Patch [4]: [PATCH v3 4/6] hwmon: (lm63) Add Sensylink CTF2301 support ---
commit 951fc5c354ae91e1c67e85c453464f893528203b
Author: Troy Mitchell <troy.mitchell@linux.dev>

hwmon: (lm63) Add Sensylink CTF2301 support

Add Sensylink CTF2301 support to the LM63 driver. CTF2301 follows
the LM63-style temperature, tachometer, and PWM register layout,
while using a 12-bit local temperature register and requiring the
ALERT/TACH pin to be configured for tachometer input.

Register an optional thermal cooling device when the device tree
node provides #cooling-cells.

> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 2bfbcc033d599..abb1af8664fb3 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1501,10 +1501,10 @@ config SENSORS_LM63
>  	depends on I2C

[Severity: High]
Could this lead to a linker error if the user configures the kernel with
CONFIG_THERMAL=m and CONFIG_SENSORS_LM63=y?

CONFIG_THERMAL_OF is a boolean, so it can be enabled even when the thermal
subsystem is built as a module. If the driver is built-in, the IS_ENABLED
check in lm63_probe evaluates to true, causing the built-in driver to call
devm_thermal_of_cooling_device_register from the modular thermal_sys.

Should there be a dependency like depends on THERMAL || THERMAL=n here to
prevent this configuration?

[ ... ]

> diff --git a/drivers/hwmon/lm63.c b/drivers/hwmon/lm63.c
> index e2a429e579ac1..3887f02b924d1 100644
> --- a/drivers/hwmon/lm63.c
> +++ b/drivers/hwmon/lm63.c

[ ... ]

> @@ -512,35 +573,55 @@ static ssize_t pwm1_freq_store(struct device *dev,
>  
>  	if (slow_clock)
> -		data->config_fan |= 0x08;
> +		config_fan |= 0x08;
>  	else
> -		data->config_fan &= ~0x08;
> -	i2c_smbus_write_byte_data(client, LM63_REG_CONFIG_FAN, data->config_fan);
> -	i2c_smbus_write_byte_data(client, LM63_REG_PWM_FREQ, pfr);
> +		config_fan &= ~0x08;
> +	ret = i2c_smbus_write_byte_data(client, LM63_REG_PWM_FREQ, pfr);
> +	if (ret)
> +		goto unlock;
> +	ret = i2c_smbus_write_byte_data(client, LM63_REG_CONFIG_FAN,
> +					config_fan);
> +	if (ret)
> +		goto unlock;
> +
> +	data->config_fan = config_fan;
> +	data->pwm1_freq = pfr;
> +	data->pwm_highres = !slow_clock && pfr == 8 &&
> +				(config_enhanced & 0x10);
> +unlock:
>  	mutex_unlock(&data->update_lock);

[Severity: Medium]
Is it possible for the hardware state to desynchronize from the software
state if an I2C error occurs here?

If a user writes to the pwm1_freq sysfs attribute and the first I2C write
succeeds, but the second fails, the function aborts early via goto unlock.
Because the internal data structure is only updated at the end of the
function, the early abort leaves the hardware updated while the software
caches remain unmodified.

Would it be safer to update the software state incrementally as the writes
succeed, or revert the hardware state on failure?

[ ... ]

> @@ -555,6 +636,11 @@ static ssize_t show_local_temp8(struct device *dev,
>  {
>  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
>  	struct lm63_data *data = lm63_update_device(dev);
> +
> +	if (data->kind == ctf2301)
> +		return sprintf(buf, "%d\n", TEMP12_FROM_REG(attr->index ?
> +				       data->temp1_max : data->temp1_input));
> +

[Severity: Medium]
Does this lockless read introduce a data race?

The 16-bit variables data->temp1_max and data->temp1_input are read here
without holding data->update_lock. However, these values are updated under
the lock in set_temp8 when a user concurrently modifies the temperature
limit via sysfs.

Could this result in a torn read or reading partially updated state, causing
an incorrect temperature limit to be reported to user-space?

>  	return sprintf(buf, "%d\n", TEMP8_FROM_REG(data->temp8[attr->index]));
>  }

[ ... ]

> @@ -1273,11 +1519,26 @@ static int lm63_probe(struct i2c_client *client)
>  	if (data->kind == lm96163) {
>  		data->groups[groups++] = &lm63_group_temp2_type;
>  		data->groups[groups++] = &lm63_group_extra_lut;
> +	} else if (data->kind == ctf2301) {
> +		data->groups[groups++] = &lm63_group_extra_lut;
>  	}
>  
>  	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
>  							   data, data->groups);
> -	return PTR_ERR_OR_ZERO(hwmon_dev);
> +	if (IS_ERR(hwmon_dev))
> +		return PTR_ERR(hwmon_dev);
> +
> +	if (IS_ENABLED(CONFIG_THERMAL_OF) &&
> +	    of_property_present(dev->of_node, "#cooling-cells")) {
> +		cdev = devm_thermal_of_cooling_device_register(dev, 0,
> +							       client->name,
> +							       data,
> +							       &lm63_cooling_ops);

[Severity: High]
Could calling devm_thermal_of_cooling_device_register without a proper Kconfig
dependency cause undefined references during the build?

As noted above, if CONFIG_THERMAL=m and CONFIG_SENSORS_LM63=y, this path will
be reached by a built-in driver trying to resolve a symbol exported by a
loadable module.

> +		if (IS_ERR(cdev))
> +			return PTR_ERR(cdev);
> +	}
> +
> +	return 0;
>  }

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-ctl2301-v3-0-fd4b8ffb5b0d@linux.dev?part=4

Re: [PATCH v3 4/6] hwmon: (lm63) Add Sensylink CTF2301 support

[Guenter Roeck]

On Wed, Aug 05, 2026 at 02:00:54AM -0700, Troy Mitchell wrote:
> Add Sensylink CTF2301 support to the LM63 driver. CTF2301 follows
> the LM63-style temperature, tachometer, and PWM register layout,
> while using a 12-bit local temperature register and requiring the
> ALERT/TACH pin to be configured for tachometer input.
> 
> Register an optional thermal cooling device when the device tree
> node provides #cooling-cells, allowing thermal zones to control
> the fan through the existing PWM path without changing behavior
> for existing LM63-family users.
> 
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
> ---
>  Documentation/hwmon/lm63.rst |  22 +++
>  drivers/hwmon/Kconfig        |   8 +-
>  drivers/hwmon/lm63.c         | 414 +++++++++++++++++++++++++++++++++++--------
>  3 files changed, 366 insertions(+), 78 deletions(-)
> 
> diff --git a/Documentation/hwmon/lm63.rst b/Documentation/hwmon/lm63.rst
> index 9e27367d7405..c40bd0dfe591 100644
> --- a/Documentation/hwmon/lm63.rst
> +++ b/Documentation/hwmon/lm63.rst
> @@ -33,6 +33,16 @@ Supported chips:
>  
>  	       http://www.national.com/pf/LM/LM96163.html
>  
> +  * Sensylink CTF2301
> +
> +    Prefix: 'ctf2301'
> +
> +    Addresses scanned: none
> +
> +    Datasheet: https://www.sensylink.com/upload/1/net.sensylink.portal/1689557281035.pdf
> +
> +    Register description: https://github.com/TroyMitchell911/ctf2301-datasheet
> +
>  
>  Author: Jean Delvare <jdelvare@suse.de>
>  
> @@ -62,6 +72,8 @@ value have to be masked out. The value is still 16 bit in width.
>  
>  All temperature values are given in degrees Celsius. Resolution is 1.0
>  degree for the local temperature, 0.125 degree for the remote temperature.
> +The CTF2301 local temperature input and limit have a resolution of 0.0625
> +degree.
>  
>  The fan speed is measured using a tachometer. Contrary to most chips which
>  store the value in an 8-bit register and have a selectable clock divider
> @@ -93,3 +105,13 @@ support these GPIO lines at present.
>  The LM96163 is an enhanced version of LM63 with improved temperature accuracy
>  and better PWM resolution. For LM96163, the external temperature sensor type is
>  configurable as CPU embedded diode(1) or 3904 transistor(2).
> +
> +The CTF2301 is register-compatible with the LM63 family and provides 12 fan
> +control lookup table entries. It supports 8-bit PWM resolution when configured
> +for a 22.5 kHz PWM frequency.
> +
> +Device tree nodes may declare ``#cooling-cells`` to register the fan controller
> +with the thermal framework. The cooling state is mapped to the existing
> +``pwm1`` range from 0 to 255. The driver keeps the current automatic or manual
> +fan control mode during probe and switches to manual control when the thermal
> +framework first requests a cooling state.
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 2bfbcc033d59..abb1af8664fb 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1501,10 +1501,10 @@ config SENSORS_LM63
>  	depends on I2C

This seems to be missing the THERMAL dependency as suggested by Sashiko.

...
> -enum chips { lm63, lm64, lm96163 };
> +enum chips { lm63, lm64, lm96163, ctf2301 };

Alphabetic order, please.

> +		if (data->kind == ctf2301) {
> +			msb = i2c_smbus_read_byte_data(client,
> +						       LM63_REG_LOCAL_TEMP);
> +			lsb = i2c_smbus_read_byte_data(client,
> +						       CTF2301_REG_LOCAL_TEMP_LSB);
> +			if (msb >= 0 && lsb >= 0) {
> +				data->temp8[0] = msb;

Why keep the assignments to data->temp8[0] and data->temp8[1] ?

Thanks,
Guenter

[PATCH v3 5/6] riscv: dts: spacemit: Add K3 I2C6 pinctrl state

[Troy Mitchell]

Add the K3 I2C6 pinctrl state used by boards that route I2C6 to pads 7
and 8. Use a 25 mA drive strength, which is supported for both K3 IO
voltage domains, and leave board-specific IO voltage selection to board
files.

Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
---
 arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi b/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi
index 3ee1471f3798..e50f3e4b5536 100644
--- a/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi
@@ -78,6 +78,17 @@ gmac1-phy-0-pins {
 		};
 	};
 
+	/omit-if-no-ref/
+	i2c6_1_cfg: i2c6-1-cfg {
+		i2c6-1-pins {
+			pinmux = <K3_PADCONF(7, 6)>,	/* i2c6 scl */
+				 <K3_PADCONF(8, 6)>;	/* i2c6 sda */
+
+			bias-pull-up = <0>;
+			drive-strength = <25>;
+		};
+	};
+
 	/omit-if-no-ref/
 	i2c8_cfg: i2c8-cfg {
 		i2c8-pins {

-- 
2.55.0

Re: [PATCH v3 5/6] riscv: dts: spacemit: Add K3 I2C6 pinctrl state

[sashiko-bot]

> Add the K3 I2C6 pinctrl state used by boards that route I2C6 to pads 7
> and 8. Use a 25 mA drive strength, which is supported for both K3 IO
> voltage domains, and leave board-specific IO voltage selection to board
> files.
> 
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-ctl2301-v3-0-fd4b8ffb5b0d@linux.dev?part=5

[PATCH v3 6/6] riscv: dts: spacemit: Add CTF2301 on K3 CoM260

[Troy Mitchell]

Enable I2C6 on the K3 CoM260 module and describe the Sensylink
CTF2301 temperature sensor and fan controller at address 0x4c.

Set the I2C6 pin power source in the board-level pinctrl node
because the IO rail voltage is board-specific.

Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
---
 arch/riscv/boot/dts/spacemit/k3-com260.dtsi | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k3-com260.dtsi b/arch/riscv/boot/dts/spacemit/k3-com260.dtsi
index a38d7b738258..95a60fbb411f 100644
--- a/arch/riscv/boot/dts/spacemit/k3-com260.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k3-com260.dtsi
@@ -26,6 +26,25 @@ reg_5v_sys: regulator-5v-sys {
 	};
 };
 
+&pinctrl {
+	i2c6-1-cfg {
+		i2c6-1-pins {
+			power-source = <3300>;
+		};
+	};
+};
+
+&i2c6 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c6_1_cfg>;
+	status = "okay";
+
+	temperature-sensor@4c {
+		compatible = "sensylink,ctf2301";
+		reg = <0x4c>;
+	};
+};
+
 &i2c8 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&i2c8_cfg>;

-- 
2.55.0

Re: [PATCH v3 6/6] riscv: dts: spacemit: Add CTF2301 on K3 CoM260

[sashiko-bot]

> Enable I2C6 on the K3 CoM260 module and describe the Sensylink
> CTF2301 temperature sensor and fan controller at address 0x4c.
> 
> Set the I2C6 pin power source in the board-level pinctrl node
> because the IO rail voltage is board-specific.
> 
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805-ctl2301-v3-0-fd4b8ffb5b0d@linux.dev?part=6

Re: [PATCH v3 6/6] riscv: dts: spacemit: Add CTF2301 on K3 CoM260

[Yixun Lan]

hi Troy,

On 02:00 Wed 05 Aug     , Troy Mitchell wrote:
> Enable I2C6 on the K3 CoM260 module and describe the Sensylink
> CTF2301 temperature sensor and fan controller at address 0x4c.
> 
> Set the I2C6 pin power source in the board-level pinctrl node
> because the IO rail voltage is board-specific.
> 
> Signed-off-by: Troy Mitchell <troy.mitchell@linux.dev>
> ---
>  arch/riscv/boot/dts/spacemit/k3-com260.dtsi | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 
> diff --git a/arch/riscv/boot/dts/spacemit/k3-com260.dtsi b/arch/riscv/boot/dts/spacemit/k3-com260.dtsi
> index a38d7b738258..95a60fbb411f 100644
> --- a/arch/riscv/boot/dts/spacemit/k3-com260.dtsi
> +++ b/arch/riscv/boot/dts/spacemit/k3-com260.dtsi
> @@ -26,6 +26,25 @@ reg_5v_sys: regulator-5v-sys {
>  	};
>  };
>  
..
> +&pinctrl {
> +	i2c6-1-cfg {
I'd prefer to use the reference, keep it short & close to where it's used

 &i2c6_1_cfg

> +		i2c6-1-pins {
> +			power-source = <3300>;
> +		};
> +	};
> +};
> +
> +&i2c6 {
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&i2c6_1_cfg>;
> +	status = "okay";
> +
> +	temperature-sensor@4c {
> +		compatible = "sensylink,ctf2301";
> +		reg = <0x4c>;
> +	};
> +};
> +
>  &i2c8 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&i2c8_cfg>;
> 
> -- 
> 2.55.0
> 

-- 
Yixun Lan (dlan)