Re: [PATCH v2 2/2] hwmon:(pmbus/xdp720) Add support for efuse xdp720

From: ashish yadav

Date: Thu Apr 02 2026 - 10:17:16 EST

Hi Guenter,

Thanks for your valuable feedback and time.
Please find my response in-line.

With Best Regards,
Ashish Yadav

On Wed, Apr 1, 2026 at 9:26 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
>
> Hi,
>
> On 4/1/26 03:45, ASHISH YADAV wrote:
> > From: Ashish Yadav <ashish.yadav@xxxxxxxxxxxx>
> >
> > Add the pmbus driver for Infineon XDP720 Digital eFuse Controller.
> >
> > Signed-off-by: Ashish Yadav <ashish.yadav@xxxxxxxxxxxx>
> > ---
> > XDP720 Digital eFuse Controller provides accurate system telemetry
> > (V, I, P, T) and reports analog current at the IMON pin for post-processing.
> >
> > The Current and Power measurement depends on the RIMON and GIMON values.
> > Please look into data sheet sections 5.4.2 and 5.4.4 for more details:
> > https://www.infineon.com/assets/row/public/documents/24/49/infineon-xdp720-001-datasheet-en.pdf
> >
> > The GIMON (microA/A) depends on the 10th bit of TELEMETRY_AVG PMBUS Register.
> > The value of RIMON (kohm) can be provided by the user through device tree using
> > infineon,rimon-micro-ohms property.
>
> Please have a look at
>
> https://sashiko.dev/#/patchset/20260401104550.115715-1-Ashish.Yadav%40infineon.com
>
> Main concern is the power measurement range, but also please use 1000000000000ULL
> as suggested.

Sure, We will look into it and get back to you.

> Thanks,
> Guenter
>
> > ---
> > drivers/hwmon/pmbus/Kconfig | 9 +++
> > drivers/hwmon/pmbus/Makefile | 1 +
> > drivers/hwmon/pmbus/xdp720.c | 123 +++++++++++++++++++++++++++++++++++
> > 3 files changed, 133 insertions(+)
> > create mode 100644 drivers/hwmon/pmbus/xdp720.c
> >
> > diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
> > index fc1273abe357..c419e3ecce90 100644
> > --- a/drivers/hwmon/pmbus/Kconfig
> > +++ b/drivers/hwmon/pmbus/Kconfig
> > @@ -702,6 +702,15 @@ config SENSORS_XDP710
> > This driver can also be built as a module. If so, the module will
> > be called xdp710.
> >
> > +config SENSORS_XDP720
> > + tristate "Infineon XDP720 family"
> > + help
> > + If you say yes here you get hardware monitoring support for Infineon
> > + XDP720.
> > +
> > + This driver can also be built as a module. If so, the module will
> > + be called xdp720.
> > +
> > config SENSORS_XDPE152
> > tristate "Infineon XDPE152 family"
> > help
> > diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
> > index d6c86924f887..1cac7ccae79f 100644
> > --- a/drivers/hwmon/pmbus/Makefile
> > +++ b/drivers/hwmon/pmbus/Makefile
> > @@ -68,6 +68,7 @@ obj-$(CONFIG_SENSORS_TPS546D24) += tps546d24.o
> > obj-$(CONFIG_SENSORS_UCD9000) += ucd9000.o
> > obj-$(CONFIG_SENSORS_UCD9200) += ucd9200.o
> > obj-$(CONFIG_SENSORS_XDP710) += xdp710.o
> > +obj-$(CONFIG_SENSORS_XDP720) += xdp720.o
> > obj-$(CONFIG_SENSORS_XDPE122) += xdpe12284.o
> > obj-$(CONFIG_SENSORS_XDPE152) += xdpe152c4.o
> > obj-$(CONFIG_SENSORS_ZL6100) += zl6100.o
> > diff --git a/drivers/hwmon/pmbus/xdp720.c b/drivers/hwmon/pmbus/xdp720.c
> > new file mode 100644
> > index 000000000000..382dc3f9ce80
> > --- /dev/null
> > +++ b/drivers/hwmon/pmbus/xdp720.c
> > @@ -0,0 +1,123 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Hardware monitoring driver for Infineon XDP720 Digital eFuse Controller
> > + *
> > + * Copyright (c) 2026 Infineon Technologies. All rights reserved.
> > + */
> > +
> > +#include <linux/i2c.h>
> > +#include <linux/module.h>
> > +#include <linux/init.h>
> > +#include <linux/kernel.h>
> > +#include <linux/of_device.h>
> > +#include <linux/bitops.h>
> > +#include <linux/math64.h>
> > +#include "pmbus.h"
> > +
> > +/*
> > + * The IMON resistor required to generate the system overcurrent protection.
> > + * Arbitrary default Rimon value: 2k Ohm
> > + */
> > +#define XDP720_DEFAULT_RIMON 2000000000 /* 2k ohm */
> > +#define XDP720_TELEMETRY_AVG 0xE9
> > +
> > +static struct pmbus_driver_info xdp720_info = {
> > + .pages = 1,
> > + .format[PSC_VOLTAGE_IN] = direct,
> > + .format[PSC_VOLTAGE_OUT] = direct,
> > + .format[PSC_CURRENT_OUT] = direct,
> > + .format[PSC_POWER] = direct,
> > + .format[PSC_TEMPERATURE] = direct,
> > +
> > + .m[PSC_VOLTAGE_IN] = 4653,
> > + .b[PSC_VOLTAGE_IN] = 0,
> > + .R[PSC_VOLTAGE_IN] = -2,
> > + .m[PSC_VOLTAGE_OUT] = 4653,
> > + .b[PSC_VOLTAGE_OUT] = 0,
> > + .R[PSC_VOLTAGE_OUT] = -2,
> > + /*
> > + * Current and Power measurement depends on the RIMON (kOhm) and
> > + * GIMON(microA/A) values.
> > + */
> > + .m[PSC_CURRENT_OUT] = 24668,
> > + .b[PSC_CURRENT_OUT] = 0,
> > + .R[PSC_CURRENT_OUT] = -4,
> > + .m[PSC_POWER] = 4486,
> > + .b[PSC_POWER] = 0,
> > + .R[PSC_POWER] = -1,
> > + .m[PSC_TEMPERATURE] = 54,
> > + .b[PSC_TEMPERATURE] = 22521,
> > + .R[PSC_TEMPERATURE] = -1,
> > +
> > + .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_PIN |
> > + PMBUS_HAVE_TEMP | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_INPUT |
> > + PMBUS_HAVE_STATUS_TEMP,
> > +};
> > +
> > +static int xdp720_probe(struct i2c_client *client)
> > +{
> > + struct pmbus_driver_info *info;
> > + int ret;
> > + u32 rimon;
> > + int gimon;
> > +
> > + info = devm_kmemdup(&client->dev, &xdp720_info, sizeof(*info),
> > + GFP_KERNEL);
> > + if (!info)
> > + return -ENOMEM;
> > +
> > + ret = i2c_smbus_read_word_data(client, XDP720_TELEMETRY_AVG);
> > + if (ret < 0) {
> > + dev_err(&client->dev, "Can't get TELEMETRY_AVG\n");
> > + return ret;
> > + }
> > +
> > + ret >>= 10; /* 10th bit of TELEMETRY_AVG REG for GIMON Value */
> > + ret &= GENMASK(0, 0);
> > + if (ret == 1)
> > + gimon = 18200; /* output gain 18.2 microA/A */
> > + else
> > + gimon = 9100; /* output gain 9.1 microA/A */
> > +
> > + if (of_property_read_u32(client->dev.of_node,
> > + "infineon,rimon-micro-ohms", &rimon))
> > + rimon = XDP720_DEFAULT_RIMON; /* Default if not set via DT */
> > + if (rimon == 0)
> > + return -EINVAL;
> > +
> > + /* Adapt the current and power scale for each instance */
> > + info->m[PSC_CURRENT_OUT] = DIV64_U64_ROUND_CLOSEST((u64)
> > + info->m[PSC_CURRENT_OUT] * rimon * gimon, 1000000000000);
> > + info->m[PSC_POWER] = DIV64_U64_ROUND_CLOSEST((u64)
> > + info->m[PSC_POWER] * rimon * gimon, 1000000000000);
> > +
> > + return pmbus_do_probe(client, info);
> > +}
> > +
> > +static const struct of_device_id xdp720_of_match[] = {
> > + { .compatible = "infineon,xdp720" },
> > + {}
> > +};
> > +MODULE_DEVICE_TABLE(of, xdp720_of_match);
> > +
> > +static const struct i2c_device_id xdp720_id[] = {
> > + { "xdp720" },
> > + {}
> > +};
> > +MODULE_DEVICE_TABLE(i2c, xdp720_id);
> > +
> > +static struct i2c_driver xdp720_driver = {
> > + .driver = {
> > + .name = "xdp720",
> > + .of_match_table = xdp720_of_match,
> > + },
> > + .probe = xdp720_probe,
> > + .id_table = xdp720_id,
> > +};
> > +
> > +module_i2c_driver(xdp720_driver);
> > +
> > +MODULE_AUTHOR("Ashish Yadav <ashish.yadav@xxxxxxxxxxxx>");
> > +MODULE_DESCRIPTION("PMBus driver for Infineon XDP720 Digital eFuse Controller");
> > +MODULE_LICENSE("GPL");
> > +MODULE_IMPORT_NS("PMBUS");
>