hwmon: Add Maxim MAX6620 hardware monitoring driver

Add hardware monitoring driver for Maxim MAX6620 Fan controller Originally-from: L. Grunenberg <contact@lgrunenberg.de> Originally-from: Cumulus Networks <support@cumulusnetworks.com> Originally-from: Shuotian Cheng <shuche@microsoft.com> Signed-off-by: Arun Saravanan Balachandran <Arun_Saravanan_Balac@dell.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Nevuly · Oct 12, 2021 · e8ac01e · e8ac01e
1 parent d73287e
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diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
@@ -130,6 +130,7 @@ Hardware Monitoring Kernel Drivers
    max31785
    max31790
    max34440
+   max6620
    max6639
    max6642
    max6650

diff --git a/Documentation/hwmon/max6620.rst b/Documentation/hwmon/max6620.rst
@@ -0,0 +1,46 @@
+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+Kernel driver max6620
+=====================
+
+Supported chips:
+
+    Maxim MAX6620
+
+    Prefix: 'max6620'
+
+    Addresses scanned: none
+
+    Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6620.pdf
+
+Authors:
+    - L\. Grunenberg <contact@lgrunenberg.de>
+    - Cumulus Networks <support@cumulusnetworks.com>
+    - Shuotian Cheng <shuche@microsoft.com>
+    - Arun Saravanan Balachandran <Arun_Saravanan_Balac@dell.com>
+
+Description
+-----------
+
+This driver implements support for Maxim MAX6620 fan controller.
+
+The driver configures the fan controller in RPM mode. To give the readings more
+range or accuracy, the desired value can be set by a programmable register
+(1, 2, 4, 8, 16 or 32). Set higher values for larger speeds.
+
+The driver provides the following sensor access in sysfs:
+
+================ ======= =====================================================
+fan[1-4]_alarm   ro      Fan alarm.
+fan[1-4]_div     rw      Sets the nominal RPM range of the fan. Valid values
+                         are 1, 2, 4, 8, 16 and 32.
+fan[1-4]_input   ro      Fan speed in RPM.
+fan[1-4]_target  rw      Desired fan speed in RPM.
+================ ======= =====================================================
+
+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.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
@@ -1032,6 +1032,16 @@ config SENSORS_MAX31730
 	  This driver can also be built as a module. If so, the module
 	  will be called max31730.
 
+config SENSORS_MAX6620
+	tristate "Maxim MAX6620 fan controller"
+	depends on I2C
+	help
+	  If you say yes here you get support for the MAX6620
+	  fan controller.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called max6620.
+
 config SENSORS_MAX6621
 	tristate "Maxim MAX6621 sensor chip"
 	depends on I2C

diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
@@ -135,6 +135,7 @@ obj-$(CONFIG_SENSORS_MAX1668)	+= max1668.o
 obj-$(CONFIG_SENSORS_MAX197)	+= max197.o
 obj-$(CONFIG_SENSORS_MAX31722)	+= max31722.o
 obj-$(CONFIG_SENSORS_MAX31730)	+= max31730.o
+obj-$(CONFIG_SENSORS_MAX6620)	+= max6620.o
 obj-$(CONFIG_SENSORS_MAX6621)	+= max6621.o
 obj-$(CONFIG_SENSORS_MAX6639)	+= max6639.o
 obj-$(CONFIG_SENSORS_MAX6642)	+= max6642.o
-Original file line number
+Diff line change
@@ Expand Up / @@ -130,6 +130,7 @@ Hardware Monitoring Kernel Drivers @@
        max31785
        max31790
        max34440
+       max6620
        max6639
        max6642
        max6650
@@ Expand Down @@