Re: [PATCH 1/3] hwmon: (pmbus) Add driver for Delta DPS-920AB PSU

From: Guenter Roeck
Date: Fri Apr 30 2021 - 09:48:18 EST


On Fri, Apr 30, 2021 at 03:27:33PM +0200, Robert Marko wrote:
> This adds support for the Delta DPS-920AB PSU.
>
> Only missing feature is fan control which the PSU supports.
>
> Signed-off-by: Robert Marko <robert.marko@xxxxxxxxxx>
> ---
> Documentation/hwmon/dps920ab.rst | 80 ++++++++++++++++++++++++++++++++
> Documentation/hwmon/index.rst | 1 +
> drivers/hwmon/pmbus/Kconfig | 9 ++++
> drivers/hwmon/pmbus/Makefile | 1 +
> drivers/hwmon/pmbus/dps920ab.c | 63 +++++++++++++++++++++++++
> 5 files changed, 154 insertions(+)
> create mode 100644 Documentation/hwmon/dps920ab.rst
> create mode 100644 drivers/hwmon/pmbus/dps920ab.c
>
> diff --git a/Documentation/hwmon/dps920ab.rst b/Documentation/hwmon/dps920ab.rst
> new file mode 100644
> index 000000000000..df0aef530c7e
> --- /dev/null
> +++ b/Documentation/hwmon/dps920ab.rst
> @@ -0,0 +1,80 @@
> +.. SPDX-License-Identifier: GPL-2.0-or-later
> +
> +Kernel driver dps920ab
> +========================
> +
> +Supported chips:
> +
> + * Delta DPS920AB
> +
> + Prefix: 'dps920ab'
> +
> + Addresses scanned: -
> +
> +Authors:
> + Robert Marko <robert.marko@xxxxxxxxxx>
> +
> +
> +Description
> +-----------
> +
> +This driver implements support for Delta DPS920AB 920W 54V DC single output
> +power supply with PMBus support.
> +
> +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.
> +
> +
> +Sysfs entries
> +-------------
> +
> +======================= ======================================================
> +curr1_label "iin"
> +curr1_input Measured input current
> +curr1_crit Critical maximum current
> +curr1_crit_alarm Current critical high alarm
> +
> +curr2_label "iout1"
> +curr2_input Measured output current
> +curr2_crit Critical maximum current
> +curr2_crit_alarm Current critical high alarm
> +
> +in1_label "vin"
> +in1_input Measured input voltage
> +in1_lcrit Critical minimum input voltage
> +in1_lcrit_alarm Input voltage critical low alarm
> +in1_crit Critical maximum input voltage
> +in1_crit_alarm Input voltage critical high alarm
> +
> +in2_label "vout1"
> +in2_input Measured output voltage
> +in2_lcrit Critical minimum output voltage
> +in2_lcrit_alarm Output voltage critical low alarm
> +in2_crit Critical maximum output voltage
> +in2_crit_alarm Output voltage critical high alarm
> +
> +power1_label "pin"
> +power1_input Measured input power
> +power1_alarm Input power high alarm
> +
> +power2_label "pout1"
> +power2_input Measured output power
> +
> +temp[1-2]_input Measured temperature
> +temp[1-2]_crit Critical high temperature
> +temp[1-2]_crit_alarm Chip temperature critical high alarm
> +temp[1-2]_max Maximum temperature
> +temp[1-2]_max_alarm Chip temperature high alarm
> +
> +fan1_alarm Fan 1 warning.
> +fan1_fault Fan 1 fault.
> +fan1_input Fan 1 speed in RPM.
> +======================= ======================================================
> diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
> index 8d5a2df1ecb6..b24436f22052 100644
> --- a/Documentation/hwmon/index.rst
> +++ b/Documentation/hwmon/index.rst
> @@ -54,6 +54,7 @@ Hardware Monitoring Kernel Drivers
> dell-smm-hwmon
> dme1737
> drivetemp
> + dps920ab
> ds1621
> ds620
> emc1403
> diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
> index 32d2fc850621..865ade0aa205 100644
> --- a/drivers/hwmon/pmbus/Kconfig
> +++ b/drivers/hwmon/pmbus/Kconfig
> @@ -66,6 +66,15 @@ config SENSORS_IBM_CFFPS
> This driver can also be built as a module. If so, the module will
> be called ibm-cffps.
>
> +config SENSORS_DPS920AB
> + tristate "Delta DPS920AB Power Supply"
> + help
> + If you say yes here you get hardware monitoring support for Delta
> + DPS920AB Power Supplies.
> +
> + This driver can also be built as a module. If so, the module will
> + be called dps920ab.
> +
> config SENSORS_INSPUR_IPSPS
> tristate "INSPUR Power System Power Supply"
> help
> diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
> index 6a4ba0fdc1db..f59ba0123d68 100644
> --- a/drivers/hwmon/pmbus/Makefile
> +++ b/drivers/hwmon/pmbus/Makefile
> @@ -9,6 +9,7 @@ obj-$(CONFIG_SENSORS_ADM1266) += adm1266.o
> obj-$(CONFIG_SENSORS_ADM1275) += adm1275.o
> obj-$(CONFIG_SENSORS_BEL_PFE) += bel-pfe.o
> obj-$(CONFIG_SENSORS_IBM_CFFPS) += ibm-cffps.o
> +obj-$(CONFIG_SENSORS_DPS920AB) += dps920ab.o
> obj-$(CONFIG_SENSORS_INSPUR_IPSPS) += inspur-ipsps.o
> obj-$(CONFIG_SENSORS_IR35221) += ir35221.o
> obj-$(CONFIG_SENSORS_IR38064) += ir38064.o
> diff --git a/drivers/hwmon/pmbus/dps920ab.c b/drivers/hwmon/pmbus/dps920ab.c
> new file mode 100644
> index 000000000000..d579ed9f879c
> --- /dev/null
> +++ b/drivers/hwmon/pmbus/dps920ab.c
> @@ -0,0 +1,63 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Driver for Delta DPS920AB PSU
> + *
> + * Copyright (C) 2021 Delta Networks, Inc.
> + * Copyright (C) 2021 Sartura Ltd.
> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include "pmbus.h"
> +
> +static struct pmbus_driver_info dps920ab_info = {
> + .pages = 1,
> +
> + .format[PSC_VOLTAGE_IN] = linear,
> + .format[PSC_VOLTAGE_OUT] = linear,
> + .format[PSC_CURRENT_IN] = linear,
> + .format[PSC_CURRENT_OUT] = linear,
> + .format[PSC_POWER] = linear,
> + .format[PSC_FAN] = linear,
> + .format[PSC_TEMPERATURE] = linear,
> +
> + .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN |
> + PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
> + PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
> + PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 |
> + PMBUS_HAVE_PIN | PMBUS_HAVE_POUT |
> + PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12 |
> + PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
> +};
> +
> +static int dps920ab_probe(struct i2c_client *client)
> +{
> + if (!i2c_check_functionality(client->adapter,
> + I2C_FUNC_SMBUS_BYTE_DATA |
> + I2C_FUNC_SMBUS_WORD_DATA))
> + return -ENODEV;

This check is done in pmbus_do_probe(), and repeating it here does not add
any value.

That makes me wonder: Is this driver needed in the first place, or could
it be added to drivers/hwmon/pmbus/pmbus.c ?

Thanks,
Guenter

> +
> + return pmbus_do_probe(client, &dps920ab_info);
> +}
> +
> +static const struct of_device_id __maybe_unused dps920ab_of_match[] = {
> + { .compatible = "delta,dps920ab", },
> + {}
> +};
> +
> +MODULE_DEVICE_TABLE(of, dps920ab_of_match);
> +
> +static struct i2c_driver dps920ab_driver = {
> + .driver = {
> + .name = "dps920ab",
> + .of_match_table = of_match_ptr(dps920ab_of_match),
> + },
> + .probe_new = dps920ab_probe,
> +};
> +
> +module_i2c_driver(dps920ab_driver);
> +
> +MODULE_AUTHOR("Robert Marko <robert.marko@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("PMBus driver for Delta DPS920AB PSU");
> +MODULE_LICENSE("GPL");
> --
> 2.31.1
>