hwmon: (pmbus) add driver for BEL PFE1100 and PFE3000

Add "bel-pfe" pmbus driver to support hardware monitoring for BEL PFE1100
and PFE3000 power supplies.

Signed-off-by: Tao Ren <rentao.bupt@gmail.com>
Link: https://lore.kernel.org/r/20191029182054.32279-2-rentao.bupt@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/pmbus/Kconfig

@@ -36,6 +36,15 @@ config SENSORS_ADM1275
 	  This driver can also be built as a module. If so, the module will
 	  be called adm1275.
 
+config SENSORS_BEL_PFE
+	tristate "Bel PFE Compatible Power Supplies"
+	help
+	  If you say yes here you get hardware monitoring support for BEL
+	  PFE1100 and PFE3000 Power Supplies.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called bel-pfe.
+
 config SENSORS_IBM_CFFPS
 	tristate "IBM Common Form Factor Power Supply"
 	depends on LEDS_CLASS

drivers/hwmon/pmbus/Makefile

@@ -6,6 +6,7 @@
 obj-$(CONFIG_PMBUS)		+= pmbus_core.o
 obj-$(CONFIG_SENSORS_PMBUS)	+= pmbus.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_INSPUR_IPSPS) += inspur-ipsps.o
 obj-$(CONFIG_SENSORS_IR35221)	+= ir35221.o

drivers/hwmon/pmbus/bel-pfe.c

@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hardware monitoring driver for BEL PFE family power supplies.
+ *
+ * Copyright (c) 2019 Facebook Inc.
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pmbus.h>
+
+#include "pmbus.h"
+
+enum chips {pfe1100, pfe3000};
+
+/*
+ * Disable status check for pfe3000 devices, because some devices report
+ * communication error (invalid command) for VOUT_MODE command (0x20)
+ * although correct VOUT_MODE (0x16) is returned: it leads to incorrect
+ * exponent in linear mode.
+ */
+static struct pmbus_platform_data pfe3000_plat_data = {
+	.flags = PMBUS_SKIP_STATUS_CHECK,
+};
+
+static struct pmbus_driver_info pfe_driver_info[] = {
+	[pfe1100] = {
+		.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_TEMPERATURE] = linear,
+		.format[PSC_FAN] = linear,
+
+		.func[0] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
+			   PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
+			   PMBUS_HAVE_POUT |
+			   PMBUS_HAVE_VIN | PMBUS_HAVE_IIN |
+			   PMBUS_HAVE_PIN | PMBUS_HAVE_STATUS_INPUT |
+			   PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 |
+			   PMBUS_HAVE_STATUS_TEMP |
+			   PMBUS_HAVE_FAN12,
+	},
+
+	[pfe3000] = {
+		.pages = 7,
+		.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_TEMPERATURE] = linear,
+		.format[PSC_FAN] = linear,
+
+		/* Page 0: V1. */
+		.func[0] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
+			   PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
+			   PMBUS_HAVE_POUT | PMBUS_HAVE_FAN12 |
+			   PMBUS_HAVE_VIN | PMBUS_HAVE_IIN |
+			   PMBUS_HAVE_PIN | PMBUS_HAVE_STATUS_INPUT |
+			   PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 |
+			   PMBUS_HAVE_TEMP3 | PMBUS_HAVE_STATUS_TEMP |
+			   PMBUS_HAVE_VCAP,
+
+		/* Page 1: Vsb. */
+		.func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
+			   PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
+			   PMBUS_HAVE_PIN | PMBUS_HAVE_STATUS_INPUT |
+			   PMBUS_HAVE_POUT,
+
+		/*
+		 * Page 2: V1 Ishare.
+		 * Page 3: Reserved.
+		 * Page 4: V1 Cathode.
+		 * Page 5: Vsb Cathode.
+		 * Page 6: V1 Sense.
+		 */
+		.func[2] = PMBUS_HAVE_VOUT,
+		.func[4] = PMBUS_HAVE_VOUT,
+		.func[5] = PMBUS_HAVE_VOUT,
+		.func[6] = PMBUS_HAVE_VOUT,
+	},
+};
+
+static int pfe_pmbus_probe(struct i2c_client *client,
+			   const struct i2c_device_id *id)
+{
+	int model;
+
+	model = (int)id->driver_data;
+
+	/*
+	 * PFE3000-12-069RA devices may not stay in page 0 during device
+	 * probe which leads to probe failure (read status word failed).
+	 * So let's set the device to page 0 at the beginning.
+	 */
+	if (model == pfe3000) {
+		client->dev.platform_data = &pfe3000_plat_data;
+		i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
+	}
+
+	return pmbus_do_probe(client, id, &pfe_driver_info[model]);
+}
+
+static const struct i2c_device_id pfe_device_id[] = {
+	{"pfe1100", pfe1100},
+	{"pfe3000", pfe3000},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, pfe_device_id);
+
+static struct i2c_driver pfe_pmbus_driver = {
+	.driver = {
+		   .name = "bel-pfe",
+	},
+	.probe = pfe_pmbus_probe,
+	.remove = pmbus_do_remove,
+	.id_table = pfe_device_id,
+};
+
+module_i2c_driver(pfe_pmbus_driver);
+
+MODULE_AUTHOR("Tao Ren <rentao.bupt@gmail.com>");
+MODULE_DESCRIPTION("PMBus driver for BEL PFE Family Power Supplies");
+MODULE_LICENSE("GPL");