hwmon: (pmbus/ir38064) Add driver for Infineon IR38064 Voltage Regulator

Add the pmbus driver for the Infineon ir38064 voltage regulator.

VOUT_MODE is not supported by the device.  The driver fakes linear16
mode with exponent value -8.

The device supports VOUT_PEAK, IOUT_PEAK, and TEMPERATURE_PEAK, however
this driver does not enable them.

Signed-off-by: Maxim Sloyko <maxims@google.com>
Signed-off-by: Patrick Venture <venture@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

3 files changed, 75 insertions, 0 deletions

diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 629cb45f8557..de87abab990e 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -54,6 +54,15 @@ config SENSORS_IR35221
 	  This driver can also be built as a module. If so, the module will
 	  be called ir35521.
 
+config SENSORS_IR38064
+	tristate "Infineon IR38064"
+	help
+	  If you say yes here you get hardware monitoring support for Infineon
+	  IR38064.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called ir38064.
+
 config SENSORS_LM25066
 	tristate "National Semiconductor LM25066 and compatibles"
 	help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index ea0e39518c21..7d1fa6b3c8c9 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_SENSORS_PMBUS)	+= pmbus.o
 obj-$(CONFIG_SENSORS_ADM1275)	+= adm1275.o
 obj-$(CONFIG_SENSORS_IBM_CFFPS)	+= ibm-cffps.o
 obj-$(CONFIG_SENSORS_IR35221)	+= ir35221.o
+obj-$(CONFIG_SENSORS_IR38064)	+= ir38064.o
 obj-$(CONFIG_SENSORS_LM25066)	+= lm25066.o
 obj-$(CONFIG_SENSORS_LTC2978)	+= ltc2978.o
 obj-$(CONFIG_SENSORS_LTC3815)	+= ltc3815.o
diff --git a/drivers/hwmon/pmbus/ir38064.c b/drivers/hwmon/pmbus/ir38064.c
new file mode 100644
index 000000000000..1820f5077f66
--- /dev/null
+++ b/drivers/hwmon/pmbus/ir38064.c
@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hardware monitoring driver for Infineon IR38064
+ *
+ * Copyright (c) 2017 Google Inc
+ *
+ * VOUT_MODE is not supported by the device. The driver fakes VOUT linear16
+ * mode with exponent value -8 as direct mode with m=256/b=0/R=0.
+ *          
+ * The device supports VOUT_PEAK, IOUT_PEAK, and TEMPERATURE_PEAK, however
+ * this driver does not currently support them.
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include "pmbus.h"
+
+static struct pmbus_driver_info ir38064_info = {
+	.pages = 1,
+	.format[PSC_VOLTAGE_IN] = linear,
+	.format[PSC_VOLTAGE_OUT] = direct,
+	.format[PSC_CURRENT_OUT] = linear,
+	.format[PSC_POWER] = linear,
+	.format[PSC_TEMPERATURE] = linear,
+	.m[PSC_VOLTAGE_OUT] = 256,
+	.b[PSC_VOLTAGE_OUT] = 0,
+	.R[PSC_VOLTAGE_OUT] = 0,
+	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
+	    | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
+	    | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
+	    | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
+	    | PMBUS_HAVE_POUT,
+};
+
+static int ir38064_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	return pmbus_do_probe(client, id, &ir38064_info);
+}
+
+static const struct i2c_device_id ir38064_id[] = {
+	{"ir38064", 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, ir38064_id);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver ir38064_driver = {
+	.driver = {
+		   .name = "ir38064",
+		   },
+	.probe = ir38064_probe,
+	.remove = pmbus_do_remove,
+	.id_table = ir38064_id,
+};
+
+module_i2c_driver(ir38064_driver);
+
+MODULE_AUTHOR("Maxim Sloyko <maxims@google.com>");
+MODULE_DESCRIPTION("PMBus driver for Infineon IR38064");
+MODULE_LICENSE("GPL");