Re: [PATCH 2/2] hwmon: (pmbus/max17616): add driver for max17616

[Guenter Roeck <linux@roeck-us.net>]

On 9/29/25 22:02, Kim Seer Paller wrote:
> Add support for MAX17616/MAX17616A current-limiter with
> overvoltage/surge, undervoltage, reverse polarity, loss of ground
> protection with PMBus interface. The PMBus interface allows monitoring
> of input/output voltages, output current and temperature.
> 
> Signed-off-by: Kim Seer Paller <kimseer.paller@analog.com>

I am a bit concerned about VOUT_UV_FAULT_LIMIT which is completely non-standard.
Did you check with real hardware that in2_lcrit is not instantiated ?

Thanks,
Guenter

> ---
>   Documentation/hwmon/index.rst    |  1 +
>   Documentation/hwmon/max17616.rst | 62 ++++++++++++++++++++++++++++++++++
>   MAINTAINERS                      |  2 ++
>   drivers/hwmon/pmbus/Kconfig      |  9 +++++
>   drivers/hwmon/pmbus/Makefile     |  1 +
>   drivers/hwmon/pmbus/max17616.c   | 73 ++++++++++++++++++++++++++++++++++++++++
>   6 files changed, 148 insertions(+)
> 
> diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
> index 51a5bdf75b08656ee6499c6b5c50a51fc4d7c210..62c5d10f16ae722dd2e6a4f8953ae24b5f541666 100644
> --- a/Documentation/hwmon/index.rst
> +++ b/Documentation/hwmon/index.rst
> @@ -151,6 +151,7 @@ Hardware Monitoring Kernel Drivers
>      max1619
>      max16601
>      max1668
> +   max17616
>      max197
>      max20730
>      max20751
> diff --git a/Documentation/hwmon/max17616.rst b/Documentation/hwmon/max17616.rst
> new file mode 100644
> index 0000000000000000000000000000000000000000..936447159f87a9c6b270b903c46b43a90caddb23
> --- /dev/null
> +++ b/Documentation/hwmon/max17616.rst
> @@ -0,0 +1,62 @@
> +.. SPDX-License-Identifier: GPL-2.0
> +
> +Kernel driver max17616
> +====================
> +
> +Supported chips:
> +
> +  * Analog Devices MAX17616/MAX17616A
> +
> +    Prefix: 'max17616'
> +
> +    Addresses scanned: -
> +
> +    Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/max17616-max17616a.pdf
> +
> +Author:
> +
> +  - Kim Seer Paller <kimseer.paller@analog.com>
> +
> +
> +Description
> +-----------
> +
> +This driver supports hardware monitoring for Analog Devices MAX17616/MAX17616A
> +Current-Limiter with OV/Surge, UV, Reverse Polarity, Loss of Ground Protection
> +with PMBus Interface.
> +
> +The MAX17616/MAX17616A is a 3V to 80V, 7A current-limiter with overvoltage,
> +surge, undervoltage, reverse polarity, and loss of ground protection. 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.
> +
> +Usage Notes
> +-----------
> +
> +This driver does not auto-detect devices. You will have to instantiate
> +the devices explicitly. Please see Documentation/i2c/instantiating-devices.rst
> +for details.
> +
> +Platform data support
> +---------------------
> +
> +The driver supports standard PMBus driver platform data.
> +
> +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 89d35faf93c9d2e984b73f5c09d09044ee6eddb2..267ab428260a29c38fa508190bdfa2677bba58c8 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -14923,6 +14923,8 @@ L:	linux-hwmon@vger.kernel.org
>   S:	Supported
>   W:	https://ez.analog.com/linux-software-drivers
>   F:	Documentation/devicetree/bindings/hwmon/pmbus/adi,max17616.yaml
> +F:	Documentation/hwmon/max17616.rst
> +F:	drivers/hwmon/pmbus/max17616.c
>   
>   MAX2175 SDR TUNER DRIVER
>   M:	Ramesh Shanmugasundaram <rashanmu@gmail.com>
> diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
> index da04ff6df28bd12909c9140662d6b932a150bd97..def5faad8fdf56eb31fe216322ead57ee43a1ac5 100644
> --- a/drivers/hwmon/pmbus/Kconfig
> +++ b/drivers/hwmon/pmbus/Kconfig
> @@ -320,6 +320,15 @@ config SENSORS_MAX16601
>   	  This driver can also be built as a module. If so, the module will
>   	  be called max16601.
>   
> +config SENSORS_MAX17616
> +	tristate "Analog Devices MAX17616/MAX17616A"
> +	help
> +	  If you say yes here you get hardware monitoring support for Analog
> +	  Devices MAX17616/MAX17616A.
> +
> +	  This driver can also be built as a module. If so, the module will
> +	  be called max17616.
> +
>   config SENSORS_MAX20730
>   	tristate "Maxim MAX20710, MAX20730, MAX20734, MAX20743"
>   	help
> diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
> index 4c5ff3f32c5ecbea069dce8af3e3e8365892b278..9cebe488fdf18b2aa164c0fc2ac7d1d8ffd2b970 100644
> --- a/drivers/hwmon/pmbus/Makefile
> +++ b/drivers/hwmon/pmbus/Makefile
> @@ -31,6 +31,7 @@ obj-$(CONFIG_SENSORS_LTC4286)	+= ltc4286.o
>   obj-$(CONFIG_SENSORS_MAX15301)	+= max15301.o
>   obj-$(CONFIG_SENSORS_MAX16064)	+= max16064.o
>   obj-$(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_MAX31785)	+= max31785.o
> diff --git a/drivers/hwmon/pmbus/max17616.c b/drivers/hwmon/pmbus/max17616.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..1d4a0ddb95bb6e8349932062be0d918f935cd846
> --- /dev/null
> +++ b/drivers/hwmon/pmbus/max17616.c
> @@ -0,0 +1,73 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Hardware monitoring driver for Analog Devices MAX17616/MAX17616A
> + *
> + * Copyright (C) 2025 Analog Devices, Inc.
> + */
> +
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +
> +#include "pmbus.h"
> +
> +static struct pmbus_driver_info max17616_info = {
> +	.pages = 1,
> +	.format[PSC_VOLTAGE_IN] = direct,
> +	.m[PSC_VOLTAGE_IN] = 512,
> +	.b[PSC_VOLTAGE_IN] = -18,
> +	.R[PSC_VOLTAGE_IN] = -1,
> +
> +	.format[PSC_VOLTAGE_OUT] = direct,
> +	.m[PSC_VOLTAGE_OUT] = 512,
> +	.b[PSC_VOLTAGE_OUT] = -18,
> +	.R[PSC_VOLTAGE_OUT] = -1,
> +
> +	.format[PSC_CURRENT_OUT] = direct,
> +	.m[PSC_CURRENT_OUT] = 5845,
> +	.b[PSC_CURRENT_OUT] = 80,
> +	.R[PSC_CURRENT_OUT] = -1,
> +
> +	.format[PSC_TEMPERATURE] = direct,
> +	.m[PSC_TEMPERATURE] = 71,
> +	.b[PSC_TEMPERATURE] = 19653,
> +	.R[PSC_TEMPERATURE] = -1,
> +
> +	.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 max17616_probe(struct i2c_client *client)
> +{
> +	return pmbus_do_probe(client, &max17616_info);
> +}
> +
> +static const struct i2c_device_id max17616_id[] = {
> +	{ "max17616" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, max17616_id);
> +
> +static const struct of_device_id max17616_of_match[] = {
> +	{ .compatible = "adi,max17616" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, max17616_of_match);
> +
> +static struct i2c_driver max17616_driver = {
> +	.driver = {
> +		.name = "max17616",
> +		.of_match_table = max17616_of_match,
> +	},
> +	.probe = max17616_probe,
> +	.id_table = max17616_id,
> +};
> +module_i2c_driver(max17616_driver);
> +
> +MODULE_AUTHOR("Kim Seer Paller <kimseer.paller@analog.com>");
> +MODULE_DESCRIPTION("PMBus driver for Analog Devices MAX17616/MAX17616A");
> +MODULE_LICENSE("GPL");
> +MODULE_IMPORT_NS("PMBUS");
>