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authorAndrew Jeffery <andrew@aj.id.au>2017-11-03 15:53:02 +1100
committerGuenter Roeck <linux@roeck-us.net>2017-11-05 06:06:33 -0800
commit4d420a6a9ddd72bd25baa6e667dd0581506eeacb (patch)
tree6c819b5f598daa219a7f12806a75d3607586fa77 /drivers/hwmon
parent54b943e69691329805349440b157b36e34051a57 (diff)
downloadlinux-4d420a6a9ddd72bd25baa6e667dd0581506eeacb.tar.bz2
pmbus: Add driver for Maxim MAX31785 Intelligent Fan Controller
The Maxim MAX31785 is a PMBus device providing closed-loop, multi-channel fan management with temperature and remote voltage sensing. It supports various fan control features, including PWM frequency control, temperature hysteresis, dual tachometer measurements, and fan health monitoring. This patch presents a basic driver using only the existing features of the PMBus subsystem. Signed-off-by: Andrew Jeffery <andrew@aj.id.au> [groeck: Modified description to clarify that fan control is not yet provided] Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon')
-rw-r--r--drivers/hwmon/pmbus/Kconfig10
-rw-r--r--drivers/hwmon/pmbus/Makefile1
-rw-r--r--drivers/hwmon/pmbus/max31785.c116
3 files changed, 127 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 40019325b517..08479006c7f9 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -114,6 +114,16 @@ config SENSORS_MAX20751
This driver can also be built as a module. If so, the module will
be called max20751.
+config SENSORS_MAX31785
+ tristate "Maxim MAX31785 and compatibles"
+ default n
+ help
+ If you say yes here you get hardware monitoring support for Maxim
+ MAX31785.
+
+ This driver can also be built as a module. If so, the module will
+ be called max31785.
+
config SENSORS_MAX34440
tristate "Maxim MAX34440 and compatibles"
default n
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 459a6be3390e..a8bf0e490db9 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_SENSORS_LTC2978) += ltc2978.o
obj-$(CONFIG_SENSORS_LTC3815) += ltc3815.o
obj-$(CONFIG_SENSORS_MAX16064) += max16064.o
obj-$(CONFIG_SENSORS_MAX20751) += max20751.o
+obj-$(CONFIG_SENSORS_MAX31785) += max31785.o
obj-$(CONFIG_SENSORS_MAX34440) += max34440.o
obj-$(CONFIG_SENSORS_MAX8688) += max8688.o
obj-$(CONFIG_SENSORS_TPS40422) += tps40422.o
diff --git a/drivers/hwmon/pmbus/max31785.c b/drivers/hwmon/pmbus/max31785.c
new file mode 100644
index 000000000000..9313849d5160
--- /dev/null
+++ b/drivers/hwmon/pmbus/max31785.c
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2017 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include "pmbus.h"
+
+enum max31785_regs {
+ MFR_REVISION = 0x9b,
+};
+
+#define MAX31785_NR_PAGES 23
+
+#define MAX31785_FAN_FUNCS \
+ (PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12)
+
+#define MAX31785_TEMP_FUNCS \
+ (PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP)
+
+#define MAX31785_VOUT_FUNCS \
+ (PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT)
+
+static const struct pmbus_driver_info max31785_info = {
+ .pages = MAX31785_NR_PAGES,
+
+ /* RPM */
+ .format[PSC_FAN] = direct,
+ .m[PSC_FAN] = 1,
+ .b[PSC_FAN] = 0,
+ .R[PSC_FAN] = 0,
+ .func[0] = MAX31785_FAN_FUNCS,
+ .func[1] = MAX31785_FAN_FUNCS,
+ .func[2] = MAX31785_FAN_FUNCS,
+ .func[3] = MAX31785_FAN_FUNCS,
+ .func[4] = MAX31785_FAN_FUNCS,
+ .func[5] = MAX31785_FAN_FUNCS,
+
+ .format[PSC_TEMPERATURE] = direct,
+ .m[PSC_TEMPERATURE] = 1,
+ .b[PSC_TEMPERATURE] = 0,
+ .R[PSC_TEMPERATURE] = 2,
+ .func[6] = MAX31785_TEMP_FUNCS,
+ .func[7] = MAX31785_TEMP_FUNCS,
+ .func[8] = MAX31785_TEMP_FUNCS,
+ .func[9] = MAX31785_TEMP_FUNCS,
+ .func[10] = MAX31785_TEMP_FUNCS,
+ .func[11] = MAX31785_TEMP_FUNCS,
+ .func[12] = MAX31785_TEMP_FUNCS,
+ .func[13] = MAX31785_TEMP_FUNCS,
+ .func[14] = MAX31785_TEMP_FUNCS,
+ .func[15] = MAX31785_TEMP_FUNCS,
+ .func[16] = MAX31785_TEMP_FUNCS,
+
+ .format[PSC_VOLTAGE_OUT] = direct,
+ .m[PSC_VOLTAGE_OUT] = 1,
+ .b[PSC_VOLTAGE_OUT] = 0,
+ .R[PSC_VOLTAGE_OUT] = 0,
+ .func[17] = MAX31785_VOUT_FUNCS,
+ .func[18] = MAX31785_VOUT_FUNCS,
+ .func[19] = MAX31785_VOUT_FUNCS,
+ .func[20] = MAX31785_VOUT_FUNCS,
+ .func[21] = MAX31785_VOUT_FUNCS,
+ .func[22] = MAX31785_VOUT_FUNCS,
+};
+
+static int max31785_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ struct pmbus_driver_info *info;
+ s64 ret;
+
+ info = devm_kzalloc(dev, sizeof(struct pmbus_driver_info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ *info = max31785_info;
+
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 255);
+ if (ret < 0)
+ return ret;
+
+ return pmbus_do_probe(client, id, info);
+}
+
+static const struct i2c_device_id max31785_id[] = {
+ { "max31785", 0 },
+ { "max31785a", 0 },
+ { },
+};
+
+MODULE_DEVICE_TABLE(i2c, max31785_id);
+
+static struct i2c_driver max31785_driver = {
+ .driver = {
+ .name = "max31785",
+ },
+ .probe = max31785_probe,
+ .remove = pmbus_do_remove,
+ .id_table = max31785_id,
+};
+
+module_i2c_driver(max31785_driver);
+
+MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>");
+MODULE_DESCRIPTION("PMBus driver for the Maxim MAX31785");
+MODULE_LICENSE("GPL");