hwmon: (pmbus/crps) Add Intel CRPS185 power supply

Add the driver to monitor Intel common redundant power supply (crps185)
with hwmon over pmbus.

Signed-off-by: Ninad Palsule <ninad@linux.ibm.com>
Link: https://lore.kernel.org/r/20241217173537.192331-3-ninad@linux.ibm.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/hwmon/crps.rst

@@ -0,0 +1,97 @@
+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+Kernel driver crps
+==================
+
+Supported chips:
+
+  * Intel CRPS185
+
+    Prefix: 'crps185'
+
+    Addresses scanned: -
+
+    Datasheet: Only available under NDA.
+
+Authors:
+    Ninad Palsule <ninad@linux.ibm.com>
+
+
+Description
+-----------
+
+This driver implements support for Intel Common Redundant 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_max		Maximum input current
+curr1_max_alarm		Input maximum current high alarm
+curr1_crit		Critial high input current
+curr1_crit_alarm	Input critical current high alarm
+curr1_rated_max		Maximum rated input current
+
+curr2_label		"iout1"
+curr2_input		Measured output current
+curr2_max		Maximum output current
+curr2_max_alarm		Output maximum current high alarm
+curr2_crit		Critial high output current
+curr2_crit_alarm	Output critical current high alarm
+curr2_rated_max		Maximum rated output current
+
+in1_label		"vin"
+in1_input		Measured input voltage
+in1_crit		Critical input over voltage
+in1_crit_alarm		Critical input over voltage alarm
+in1_max			Maximum input over voltage
+in1_max_alarm		Maximum input over voltage alarm
+in1_rated_min		Minimum rated input voltage
+in1_rated_max		Maximum rated input voltage
+
+in2_label		"vout1"
+in2_input		Measured input voltage
+in2_crit		Critical input over voltage
+in2_crit_alarm		Critical input over voltage alarm
+in2_lcrit		Critical input under voltage fault
+in2_lcrit_alarm		Critical input under voltage fault alarm
+in2_max			Maximum input over voltage
+in2_max_alarm		Maximum input over voltage alarm
+in2_min			Minimum input under voltage warning
+in2_min_alarm		Minimum input under voltage warning alarm
+in2_rated_min		Minimum rated input voltage
+in2_rated_max		Maximum rated input voltage
+
+power1_label		"pin"
+power1_input		Measured input power
+power1_alarm		Input power high alarm
+power1_max  		Maximum input power
+power1_rated_max	Maximum rated input power
+
+temp[1-2]_input		Measured temperature
+temp[1-2]_crit 		Critical temperature
+temp[1-2]_crit_alarm	Critical temperature alarm
+temp[1-2]_max		Maximum temperature
+temp[1-2]_max_alarm	Maximum temperature alarm
+temp[1-2]_rated_max	Maximum rated temperature
+
+fan1_alarm		Fan 1 warning.
+fan1_fault		Fan 1 fault.
+fan1_input		Fan 1 speed in RPM.
+fan1_target		Fan 1 target.
+======================= ======================================================

Documentation/hwmon/index.rst

@@ -58,6 +58,7 @@ Hardware Monitoring Kernel Drivers
    corsair-cpro
    corsair-psu
    cros_ec_hwmon
+   crps
    da9052
    da9055
    dell-smm-hwmon

MAINTAINERS

@@ -6064,6 +6064,13 @@ L:	linux-input@vger.kernel.org
 S:	Maintained
 F:	drivers/hid/hid-creative-sb0540.c
 
+INTEL CRPS COMMON REDUNDANT PSU DRIVER
+M:	Ninad Palsule <ninad@linux.ibm.com>
+L:	linux-hwmon@vger.kernel.org
+S:	Maintained
+F:	Documentation/hwmon/crps.rst
+F:	drivers/hwmon/pmbus/crps.c
+
 CRYPTO API
 M:	Herbert Xu <herbert@gondor.apana.org.au>
 M:	"David S. Miller" <davem@davemloft.net>

drivers/hwmon/pmbus/Kconfig

@@ -85,6 +85,15 @@ config SENSORS_BPA_RS600
 	  This driver can also be built as a module. If so, the module will
 	  be called bpa-rs600.
 
+config SENSORS_CRPS
+	tristate "Intel Common Redundant Power Supply"
+	help
+	  If you say yes here you get hardware monitoring support for the Intel
+	  Common Redundant Power Supply.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called crps.
+
 config SENSORS_DELTA_AHE50DC_FAN
 	tristate "Delta AHE-50DC fan control module"
 	help

drivers/hwmon/pmbus/Makefile

@@ -62,3 +62,4 @@ obj-$(CONFIG_SENSORS_XDPE122)	+= xdpe12284.o
 obj-$(CONFIG_SENSORS_XDPE152)	+= xdpe152c4.o
 obj-$(CONFIG_SENSORS_ZL6100)	+= zl6100.o
 obj-$(CONFIG_SENSORS_PIM4328)	+= pim4328.o
+obj-$(CONFIG_SENSORS_CRPS)	+= crps.o

drivers/hwmon/pmbus/crps.c

@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2024 IBM Corp.
+ */
+
+#include <linux/i2c.h>
+#include <linux/of.h>
+#include <linux/pmbus.h>
+
+#include "pmbus.h"
+
+static const struct i2c_device_id crps_id[] = {
+	{ "intel_crps185" },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, crps_id);
+
+static struct pmbus_driver_info crps_info = {
+	.pages = 1,
+	/* PSU uses default linear data format. */
+	.func[0] = PMBUS_HAVE_PIN | PMBUS_HAVE_IOUT |
+		PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_IIN |
+		PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT |
+		PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
+		PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 |
+		PMBUS_HAVE_STATUS_TEMP |
+		PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12,
+};
+
+static int crps_probe(struct i2c_client *client)
+{
+	int rc;
+	struct device *dev = &client->dev;
+	char buf[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };
+
+	rc = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
+	if (rc < 0)
+		return dev_err_probe(dev, rc, "Failed to read PMBUS_MFR_MODEL\n");
+
+	if (rc != 7 || strncmp(buf, "03NK260", 7)) {
+		buf[rc] = '\0';
+		return dev_err_probe(dev, -ENODEV, "Model '%s' not supported\n", buf);
+	}
+
+	rc = pmbus_do_probe(client, &crps_info);
+	if (rc)
+		return dev_err_probe(dev, rc, "Failed to probe\n");
+
+	return 0;
+}
+
+static const struct of_device_id crps_of_match[] = {
+	{
+		.compatible = "intel,crps185",
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, crps_of_match);
+
+static struct i2c_driver crps_driver = {
+	.driver = {
+		.name = "crps",
+		.of_match_table = crps_of_match,
+	},
+	.probe = crps_probe,
+	.id_table = crps_id,
+};
+
+module_i2c_driver(crps_driver);
+
+MODULE_AUTHOR("Ninad Palsule");
+MODULE_DESCRIPTION("PMBus driver for Intel Common Redundant power supplies");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("PMBUS");