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* [PATCH 0/2] Add support for MAX20830 PMBUS
@ 2026-04-14  4:28 Alexis Czezar Torreno
  2026-04-14  4:28 ` [PATCH 1/2] dt-bindings: hwmon: pmbus: add max20830 Alexis Czezar Torreno
  2026-04-14  4:28 ` [PATCH 2/2] hwmon: (pmbus/max20830) add driver for max20830 Alexis Czezar Torreno
  0 siblings, 2 replies; 6+ messages in thread
From: Alexis Czezar Torreno @ 2026-04-14  4:28 UTC (permalink / raw)
  To: Guenter Roeck, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Jonathan Corbet, Shuah Khan
  Cc: linux-hwmon, devicetree, linux-kernel, linux-doc,
	Alexis Czezar Torreno

This series adds support for the Analog Devices MAX20830 step-down
switching regulator with PMBus interface.

The MAX20830 provides 2.7V to 16V input, 0.4V to 5.8V output, and up
to 30A output current. It supports monitoring of input/output voltage,
output current, and temperature via PMBus.

Datasheet: https://www.analog.com/en/products/max20830.html

Signed-off-by: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
---
Alexis Czezar Torreno (2):
      dt-bindings: hwmon: pmbus: add max20830
      hwmon: (pmbus/max20830) add driver for max20830

 .../bindings/hwmon/pmbus/adi,max20830.yaml         | 58 +++++++++++++++++
 Documentation/hwmon/index.rst                      |  1 +
 Documentation/hwmon/max20830.rst                   | 48 ++++++++++++++
 MAINTAINERS                                        |  9 +++
 drivers/hwmon/pmbus/Kconfig                        |  9 +++
 drivers/hwmon/pmbus/Makefile                       |  1 +
 drivers/hwmon/pmbus/max20830.c                     | 74 ++++++++++++++++++++++
 7 files changed, 200 insertions(+)
---
base-commit: fb447217c59a13b2fff22d94de2498c185cd9032
change-id: 20260414-dev_max20830-9460b92cf6aa

Best regards,
-- 
Alexis Czezar Torreno <alexisczezar.torreno@analog.com>


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH 1/2] dt-bindings: hwmon: pmbus: add max20830
  2026-04-14  4:28 [PATCH 0/2] Add support for MAX20830 PMBUS Alexis Czezar Torreno
@ 2026-04-14  4:28 ` Alexis Czezar Torreno
  2026-04-14  4:38   ` sashiko-bot
  2026-04-14  4:28 ` [PATCH 2/2] hwmon: (pmbus/max20830) add driver for max20830 Alexis Czezar Torreno
  1 sibling, 1 reply; 6+ messages in thread
From: Alexis Czezar Torreno @ 2026-04-14  4:28 UTC (permalink / raw)
  To: Guenter Roeck, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Jonathan Corbet, Shuah Khan
  Cc: linux-hwmon, devicetree, linux-kernel, linux-doc,
	Alexis Czezar Torreno

Add device tree documentation for MAX20830 step-down DC-DC switching
regulator with PMBus interface.

Signed-off-by: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
---
 .../bindings/hwmon/pmbus/adi,max20830.yaml         | 58 ++++++++++++++++++++++
 MAINTAINERS                                        |  7 +++
 2 files changed, 65 insertions(+)

diff --git a/Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml b/Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..b20f3be176615895e70e74bfb2a534d82d124a15
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwmon/pmbus/adi,max20830.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices MAX20830 Step-Down Switching Regulator with PMBus
+
+maintainers:
+  - Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
+
+description: |
+  The MAX20830 is a fully integrated step-down DC-DC switching regulator with
+  PMBus interface. It provides 2.7V to 16V input, 0.4V to 5.8V adjustable
+  output, and up to 30A output current. It allows monitoring of input/output
+  voltage, output current and temperature through the PMBus serial interface.
+  Datasheet:
+    https://www.analog.com/en/products/max20830.html
+
+properties:
+  compatible:
+    const: adi,max20830
+
+  reg:
+    maxItems: 1
+
+  vddh-supply:
+    description:
+      Phandle to the regulator that provides the VDDH power supply.
+
+  avdd-supply:
+    description:
+      Phandle to the regulator that provides the AVDD power supply.
+
+  ldoin-supply:
+    description:
+      Optional 2.5V to 5.5V LDO input supply.
+
+required:
+  - compatible
+  - reg
+  - vddh-supply
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        hwmon@30 {
+            compatible = "adi,max20830";
+            reg = <0x30>;
+            vddh-supply = <&vddh>;
+        };
+    };
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 0a3991c10ade20dd79cc7d1bf2a1d307ba6bd19d..031c743e979521a92ed9ac67915c178ce31727bd 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15579,6 +15579,13 @@ F:	Documentation/devicetree/bindings/hwmon/pmbus/adi,max17616.yaml
 F:	Documentation/hwmon/max17616.rst
 F:	drivers/hwmon/pmbus/max17616.c
 
+MAX20830 HARDWARE MONITOR DRIVER
+M:	Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
+L:	linux-hwmon@vger.kernel.org
+S:	Supported
+W:	https://ez.analog.com/linux-software-drivers
+F:	Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
+
 MAX2175 SDR TUNER DRIVER
 M:	Ramesh Shanmugasundaram <rashanmu@gmail.com>
 L:	linux-media@vger.kernel.org

-- 
2.34.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH 2/2] hwmon: (pmbus/max20830) add driver for max20830
  2026-04-14  4:28 [PATCH 0/2] Add support for MAX20830 PMBUS Alexis Czezar Torreno
  2026-04-14  4:28 ` [PATCH 1/2] dt-bindings: hwmon: pmbus: add max20830 Alexis Czezar Torreno
@ 2026-04-14  4:28 ` Alexis Czezar Torreno
  2026-04-14  4:56   ` sashiko-bot
  1 sibling, 1 reply; 6+ messages in thread
From: Alexis Czezar Torreno @ 2026-04-14  4:28 UTC (permalink / raw)
  To: Guenter Roeck, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Jonathan Corbet, Shuah Khan
  Cc: linux-hwmon, devicetree, linux-kernel, linux-doc,
	Alexis Czezar Torreno

Add support for MAX20830 step-down DC-DC switching regulator with
PMBus interface. It allows monitoring of input/output voltage,
output current and temperature through the PMBus serial interface.

Signed-off-by: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
---
 Documentation/hwmon/index.rst    |  1 +
 Documentation/hwmon/max20830.rst | 48 ++++++++++++++++++++++++++
 MAINTAINERS                      |  2 ++
 drivers/hwmon/pmbus/Kconfig      |  9 +++++
 drivers/hwmon/pmbus/Makefile     |  1 +
 drivers/hwmon/pmbus/max20830.c   | 74 ++++++++++++++++++++++++++++++++++++++++
 6 files changed, 135 insertions(+)

diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index 8b655e5d6b68b90c697a52c7bf526e81d370caf7..56f7eb761be76dd627a2f34135abad05203b0582 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -158,6 +158,7 @@ Hardware Monitoring Kernel Drivers
    max197
    max20730
    max20751
+   max20830
    max31722
    max31730
    max31760
diff --git a/Documentation/hwmon/max20830.rst b/Documentation/hwmon/max20830.rst
new file mode 100644
index 0000000000000000000000000000000000000000..b9dffb76059781932d383ed798cecff69e738873
--- /dev/null
+++ b/Documentation/hwmon/max20830.rst
@@ -0,0 +1,48 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Kernel driver max20830
+======================
+
+Supported chips:
+
+  * Analog Devices MAX20830
+
+    Prefix: 'max20830'
+
+    Addresses scanned: -
+
+    Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/max20830.pdf
+
+Author:
+
+  - Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
+
+
+Description
+-----------
+
+This driver supports hardware monitoring for Analog Devices MAX20830
+Step-Down Switching Regulator with PMBus Interface.
+
+The MAX20830 is a 2.7V to 16V, 30A fully integrated step-down DC-DC switching
+regulator. Through the PMBus interface, the device can monitor input/output
+voltages, output current and temperature.
+
+The driver is a client driver to the core PMBus driver. Please see
+Documentation/hwmon/pmbus.rst for details on PMBus client drivers.
+
+Sysfs entries
+-------------
+
+================= ========================================
+in1_label         "vin"
+in1_input         Measured input voltage
+in1_alarm         Input voltage alarm
+in2_label         "vout1"
+in2_input         Measured output voltage
+curr1_label       "iout1"
+curr1_input       Measured output current
+curr1_alarm       Output current alarm
+temp1_input       Measured temperature
+temp1_alarm       Chip temperature alarm
+================= ========================================
diff --git a/MAINTAINERS b/MAINTAINERS
index 031c743e979521a92ed9ac67915c178ce31727bd..d6a6745e2dae29c3b8f80bbe61c54a2f5ecd9f47 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15585,6 +15585,8 @@ L:	linux-hwmon@vger.kernel.org
 S:	Supported
 W:	https://ez.analog.com/linux-software-drivers
 F:	Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
+F:	Documentation/hwmon/max20830.rst
+F:	drivers/hwmon/pmbus/max20830.c
 
 MAX2175 SDR TUNER DRIVER
 M:	Ramesh Shanmugasundaram <rashanmu@gmail.com>
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 8f4bff375ecbc355f5ed3400855c2852ec2aa5ef..987705bf45b75b7b91ccc469247909f3c3f53d77 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -365,6 +365,15 @@ config SENSORS_MAX20751
 	  This driver can also be built as a module. If so, the module will
 	  be called max20751.
 
+config SENSORS_MAX20830
+	tristate "Analog Devices MAX20830"
+	help
+	  If you say yes here you get hardware monitoring support for Analog
+	  Devices MAX20830.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called max20830.
+
 config SENSORS_MAX31785
 	tristate "Maxim MAX31785 and compatibles"
 	help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 7129b62bc00f8a2e98de14004997752a856dfda2..bc52f930e0825a902a0dd1c9e2b44f2e8d577c35 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_SENSORS_MAX16601)	+= max16601.o
 obj-$(CONFIG_SENSORS_MAX17616)	+= max17616.o
 obj-$(CONFIG_SENSORS_MAX20730)	+= max20730.o
 obj-$(CONFIG_SENSORS_MAX20751)	+= max20751.o
+obj-$(CONFIG_SENSORS_MAX20830)	+= max20830.o
 obj-$(CONFIG_SENSORS_MAX31785)	+= max31785.o
 obj-$(CONFIG_SENSORS_MAX34440)	+= max34440.o
 obj-$(CONFIG_SENSORS_MAX8688)	+= max8688.o
diff --git a/drivers/hwmon/pmbus/max20830.c b/drivers/hwmon/pmbus/max20830.c
new file mode 100644
index 0000000000000000000000000000000000000000..bcf60fd948e3437f47267747547142704ae96378
--- /dev/null
+++ b/drivers/hwmon/pmbus/max20830.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Hardware monitoring driver for Analog Devices MAX20830
+ *
+ * Copyright (C) 2026 Analog Devices, Inc.
+ */
+
+#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include "pmbus.h"
+
+static struct pmbus_driver_info max20830_info = {
+	.pages = 1,
+	.format[PSC_VOLTAGE_IN] = linear,
+	.format[PSC_VOLTAGE_OUT] = linear,
+	.format[PSC_CURRENT_OUT] = linear,
+	.format[PSC_TEMPERATURE] = linear,
+	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
+		PMBUS_HAVE_TEMP |
+		PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
+		PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
+};
+
+static int max20830_probe(struct i2c_client *client)
+{
+	u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_SMBUS_READ_I2C_BLOCK))
+		return -ENODEV;
+
+	ret = i2c_smbus_read_i2c_block_data(client, PMBUS_IC_DEVICE_ID,
+					    I2C_SMBUS_BLOCK_MAX, buf);
+	if (ret < 0)
+		return dev_err_probe(&client->dev, ret,
+				     "Failed to read IC_DEVICE_ID\n");
+
+	buf[ret] = '\0';
+	if (ret < 9 || strncmp(buf + 1, "MAX20830", 8))
+		return dev_err_probe(&client->dev, -ENODEV,
+				     "Unsupported device: '%s'\n", buf);
+
+	return pmbus_do_probe(client, &max20830_info);
+}
+
+static const struct i2c_device_id max20830_id[] = {
+	{"max20830"},
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max20830_id);
+
+static const struct of_device_id max20830_of_match[] = {
+	{ .compatible = "adi,max20830" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, max20830_of_match);
+
+static struct i2c_driver max20830_driver = {
+	.driver = {
+		.name = "max20830",
+		.of_match_table = max20830_of_match,
+	},
+	.probe = max20830_probe,
+	.id_table = max20830_id,
+};
+
+module_i2c_driver(max20830_driver);
+
+MODULE_AUTHOR("Alexis Czezar Torreno <alexisczezar.torreno@analog.com>");
+MODULE_DESCRIPTION("PMBus driver for Analog Devices MAX20830");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(PMBUS);

-- 
2.34.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH 1/2] dt-bindings: hwmon: pmbus: add max20830
  2026-04-14  4:28 ` [PATCH 1/2] dt-bindings: hwmon: pmbus: add max20830 Alexis Czezar Torreno
@ 2026-04-14  4:38   ` sashiko-bot
  0 siblings, 0 replies; 6+ messages in thread
From: sashiko-bot @ 2026-04-14  4:38 UTC (permalink / raw)
  To: Alexis Czezar Torreno; +Cc: linux-hwmon

Sashiko AI review found 3 potential issue(s):
- [Medium] Incomplete Regulator Schema
- [Medium] Missing Hardware Capability (Interrupts)
- [Low] Devicetree Best Practices Violation (Node Name)
--

commit 20a4d8dcd2f3344ac22d7d2e974bae1ef57874ed
Author: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>

dt-bindings: hwmon: pmbus: add max20830

This commit adds device tree documentation for the MAX20830 step-down DC-DC
switching regulator with PMBus interface. It allows monitoring of voltage,
current, and temperature.

> diff --git a/Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml b/Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
> new file mode 100644
> index 0000000000000..b20f3be176615
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml
[ ... ]
> +properties:
> +  compatible:
> +    const: adi,max20830
> +
> +  reg:
> +    maxItems: 1
> +

Since this is a PMBus device that typically signals hardware faults to the
host via the standard SMBALERT# pin, should the schema define the optional
interrupts property?

> +  vddh-supply:
> +    description:
> +      Phandle to the regulator that provides the VDDH power supply.
[ ... ]
> +required:
> +  - compatible
> +  - reg
> +  - vddh-supply
> +
> +additionalProperties: false

The commit message explicitly states the MAX20830 is a step-down DC-DC
switching regulator with an adjustable output, but the schema omits any
reference to the core regulator schema or a regulators child node.

Because additionalProperties is set to false, does this prevent board
designers from describing the hardware's standard output constraints,
such as regulator-min-microvolt or regulator-max-microvolt, without
causing a schema validation error?

> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        hwmon@30 {

This isn't a bug, but the device node name in the example uses a Linux
subsystem name. Should it use a generic functional name representing the
hardware, such as regulator@30 or power-sensor@30?

> +            compatible = "adi,max20830";
> +            reg = <0x30>;
> +            vddh-supply = <&vddh>;
> +        };
> +    };
> +...

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260414-dev_max20830-v1-0-210d3f82c571@analog.com?part=1

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH 2/2] hwmon: (pmbus/max20830) add driver for max20830
  2026-04-14  4:28 ` [PATCH 2/2] hwmon: (pmbus/max20830) add driver for max20830 Alexis Czezar Torreno
@ 2026-04-14  4:56   ` sashiko-bot
  2026-04-14 14:54     ` Guenter Roeck
  0 siblings, 1 reply; 6+ messages in thread
From: sashiko-bot @ 2026-04-14  4:56 UTC (permalink / raw)
  To: Alexis Czezar Torreno; +Cc: linux-hwmon

Sashiko AI review found 3 potential issue(s):
- [Medium] The driver incorrectly uses `i2c_smbus_read_i2c_block_data` instead of `i2c_smbus_read_block_data`, violating the protocol and logging an untrusted binary buffer.
- [Low] The MODULE_IMPORT_NS macro uses an unquoted identifier, resulting in a build failure.
- [Low] The sysfs attribute `in2_alarm` is created but not documented.
--

commit 62ed9b8ac37c74adac303a0ebaea8df41fde6a85
Author: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>

hwmon: (pmbus/max20830) add driver for max20830

This commit adds support for the Analog Devices MAX20830 step-down DC-DC
switching regulator. It provides a PMBus client driver to monitor input and
output voltages, output current, and temperature.

> diff --git a/Documentation/hwmon/max20830.rst b/Documentation/hwmon/max20830.rst
> new file mode 100644
> index 0000000000000..b9dffb7605978
> --- /dev/null
> +++ b/Documentation/hwmon/max20830.rst
[ ... ]
> +================= ========================================
> +in1_label         "vin"
> +in1_input         Measured input voltage
> +in1_alarm         Input voltage alarm
> +in2_label         "vout1"
> +in2_input         Measured output voltage

This isn't a bug, but since the driver configuration enables
PMBUS_HAVE_STATUS_VOUT, it will expose the in2_alarm attribute. Should
in2_alarm be documented here alongside the other alarms?

> +curr1_label       "iout1"
> +curr1_input       Measured output current
> +curr1_alarm       Output current alarm
> +temp1_input       Measured temperature
> +temp1_alarm       Chip temperature alarm
> +================= ========================================

> diff --git a/drivers/hwmon/pmbus/max20830.c b/drivers/hwmon/pmbus/max20830.c
> new file mode 100644
> index 0000000000000..bcf60fd948e34
> --- /dev/null
> +++ b/drivers/hwmon/pmbus/max20830.c
[ ... ]
> +static int max20830_probe(struct i2c_client *client)
> +{
> +	u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
> +	int ret;
> +
> +	if (!i2c_check_functionality(client->adapter,
> +				     I2C_FUNC_SMBUS_READ_I2C_BLOCK))
> +		return -ENODEV;
> +
> +	ret = i2c_smbus_read_i2c_block_data(client, PMBUS_IC_DEVICE_ID,
> +					    I2C_SMBUS_BLOCK_MAX, buf);

Should this use i2c_smbus_read_block_data() instead?

PMBus IC_DEVICE_ID is an SMBus Block Read command, which natively returns a
length byte followed by the data. Using the I2C block read API with a
hardcoded length of 32 forces an over-read and captures the raw SMBus length
byte in buf[0].

> +	if (ret < 0)
> +		return dev_err_probe(&client->dev, ret,
> +				     "Failed to read IC_DEVICE_ID\n");
> +
> +	buf[ret] = '\0';
> +	if (ret < 9 || strncmp(buf + 1, "MAX20830", 8))
> +		return dev_err_probe(&client->dev, -ENODEV,
> +				     "Unsupported device: '%s'\n", buf);

If the device is unsupported, will logging the buffer via %s print unprintable
characters?

Since buf[0] contains the raw length byte from the block read, this could
inject control characters and trailing binary padding into the kernel log.

[ ... ]
> +MODULE_AUTHOR("Alexis Czezar Torreno <alexisczezar.torreno@analog.com>");
> +MODULE_DESCRIPTION("PMBus driver for Analog Devices MAX20830");
> +MODULE_LICENSE("GPL");
> +MODULE_IMPORT_NS(PMBUS);

Will this cause a build failure?

The MODULE_IMPORT_NS macro expects a string literal. Should PMBUS be enclosed
in quotes, like MODULE_IMPORT_NS("PMBUS")?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260414-dev_max20830-v1-0-210d3f82c571@analog.com?part=2

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH 2/2] hwmon: (pmbus/max20830) add driver for max20830
  2026-04-14  4:56   ` sashiko-bot
@ 2026-04-14 14:54     ` Guenter Roeck
  0 siblings, 0 replies; 6+ messages in thread
From: Guenter Roeck @ 2026-04-14 14:54 UTC (permalink / raw)
  To: sashiko, Alexis Czezar Torreno; +Cc: linux-hwmon

On 4/13/26 21:56, sashiko-bot@kernel.org wrote:
> Sashiko AI review found 3 potential issue(s):
> - [Medium] The driver incorrectly uses `i2c_smbus_read_i2c_block_data` instead of `i2c_smbus_read_block_data`, violating the protocol and logging an untrusted binary buffer.
> - [Low] The MODULE_IMPORT_NS macro uses an unquoted identifier, resulting in a build failure.
> - [Low] The sysfs attribute `in2_alarm` is created but not documented.
> --
> 

The reported issues seem real. Please address.

Thanks,
Guenter

> commit 62ed9b8ac37c74adac303a0ebaea8df41fde6a85
> Author: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
> 
> hwmon: (pmbus/max20830) add driver for max20830
> 
> This commit adds support for the Analog Devices MAX20830 step-down DC-DC
> switching regulator. It provides a PMBus client driver to monitor input and
> output voltages, output current, and temperature.
> 
>> diff --git a/Documentation/hwmon/max20830.rst b/Documentation/hwmon/max20830.rst
>> new file mode 100644
>> index 0000000000000..b9dffb7605978
>> --- /dev/null
>> +++ b/Documentation/hwmon/max20830.rst
> [ ... ]
>> +================= ========================================
>> +in1_label         "vin"
>> +in1_input         Measured input voltage
>> +in1_alarm         Input voltage alarm
>> +in2_label         "vout1"
>> +in2_input         Measured output voltage
> 
> This isn't a bug, but since the driver configuration enables
> PMBUS_HAVE_STATUS_VOUT, it will expose the in2_alarm attribute. Should
> in2_alarm be documented here alongside the other alarms?
> 
>> +curr1_label       "iout1"
>> +curr1_input       Measured output current
>> +curr1_alarm       Output current alarm
>> +temp1_input       Measured temperature
>> +temp1_alarm       Chip temperature alarm
>> +================= ========================================
> 
>> diff --git a/drivers/hwmon/pmbus/max20830.c b/drivers/hwmon/pmbus/max20830.c
>> new file mode 100644
>> index 0000000000000..bcf60fd948e34
>> --- /dev/null
>> +++ b/drivers/hwmon/pmbus/max20830.c
> [ ... ]
>> +static int max20830_probe(struct i2c_client *client)
>> +{
>> +	u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
>> +	int ret;
>> +
>> +	if (!i2c_check_functionality(client->adapter,
>> +				     I2C_FUNC_SMBUS_READ_I2C_BLOCK))
>> +		return -ENODEV;
>> +
>> +	ret = i2c_smbus_read_i2c_block_data(client, PMBUS_IC_DEVICE_ID,
>> +					    I2C_SMBUS_BLOCK_MAX, buf);
> 
> Should this use i2c_smbus_read_block_data() instead?
> 
> PMBus IC_DEVICE_ID is an SMBus Block Read command, which natively returns a
> length byte followed by the data. Using the I2C block read API with a
> hardcoded length of 32 forces an over-read and captures the raw SMBus length
> byte in buf[0].
> 
>> +	if (ret < 0)
>> +		return dev_err_probe(&client->dev, ret,
>> +				     "Failed to read IC_DEVICE_ID\n");
>> +
>> +	buf[ret] = '\0';
>> +	if (ret < 9 || strncmp(buf + 1, "MAX20830", 8))
>> +		return dev_err_probe(&client->dev, -ENODEV,
>> +				     "Unsupported device: '%s'\n", buf);
> 
> If the device is unsupported, will logging the buffer via %s print unprintable
> characters?
> 
> Since buf[0] contains the raw length byte from the block read, this could
> inject control characters and trailing binary padding into the kernel log.
> 
> [ ... ]
>> +MODULE_AUTHOR("Alexis Czezar Torreno <alexisczezar.torreno@analog.com>");
>> +MODULE_DESCRIPTION("PMBus driver for Analog Devices MAX20830");
>> +MODULE_LICENSE("GPL");
>> +MODULE_IMPORT_NS(PMBUS);
> 
> Will this cause a build failure?
> 
> The MODULE_IMPORT_NS macro expects a string literal. Should PMBUS be enclosed
> in quotes, like MODULE_IMPORT_NS("PMBUS")?
> 


^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2026-04-14 14:54 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-04-14  4:28 [PATCH 0/2] Add support for MAX20830 PMBUS Alexis Czezar Torreno
2026-04-14  4:28 ` [PATCH 1/2] dt-bindings: hwmon: pmbus: add max20830 Alexis Czezar Torreno
2026-04-14  4:38   ` sashiko-bot
2026-04-14  4:28 ` [PATCH 2/2] hwmon: (pmbus/max20830) add driver for max20830 Alexis Czezar Torreno
2026-04-14  4:56   ` sashiko-bot
2026-04-14 14:54     ` Guenter Roeck

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