5 files changed, 430 insertions, 0 deletions

diff --git a/Documentation/hwmon/ina2xx b/Documentation/hwmon/ina2xx
new file mode 100644
index 000000000000..f50a6cc27616
--- /dev/null
+++ b/Documentation/hwmon/ina2xx
@@ -0,0 +1,29 @@
+Kernel driver ina2xx
+====================
+
+Supported chips:
+  * Texas Instruments INA219
+    Prefix: 'ina219'
+    Addresses: I2C 0x40 - 0x4f
+    Datasheet: Publicly available at the Texas Instruments website
+               http://www.ti.com/
+
+  * Texas Instruments INA226
+    Prefix: 'ina226'
+    Addresses: I2C 0x40 - 0x4f
+    Datasheet: Publicly available at the Texas Instruments website
+               http://www.ti.com/
+
+Author: Lothar Felten <l-felten@ti.com>
+
+Description
+-----------
+
+The INA219 is a high-side current shunt and power monitor with an I2C
+interface. The INA219 monitors both shunt drop and supply voltage, with
+programmable conversion times and filtering.
+
+The INA226 is a current shunt and power monitor with an I2C interface.
+The INA226 monitors both a shunt voltage drop and bus supply voltage.
+
+The shunt value in micro-ohms can be set via platform data.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 8deedc1b9840..1c7bbd458902 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1102,6 +1102,19 @@ config SENSORS_AMC6821
           This driver can also be build as a module.  If so, the module
           will be called amc6821.
 
+config SENSORS_INA2XX
+        tristate "Texas Instruments INA219, INA226"
+        depends on I2C && EXPERIMENTAL
+        help
+          If you say yes here you get support for INA219 and INA226 power
+          monitor chips.
+
+          The INA2xx driver is configured for the default configuration of
+          the part as described in the datasheet.
+          Default value for Rshunt is 10 mOhms.
+          This driver can also be built as a module.  If so, the module
+          will be called ina2xx.
+
 config SENSORS_THMC50
         tristate "Texas Instruments THMC50 / Analog Devices ADM1022"
         depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 6d3f11f71815..e1eeac13b851 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_SENSORS_ULTRA45)	+= ultra45_env.o
 obj-$(CONFIG_SENSORS_I5K_AMB)   += i5k_amb.o
 obj-$(CONFIG_SENSORS_IBMAEM)    += ibmaem.o
 obj-$(CONFIG_SENSORS_IBMPEX)    += ibmpex.o
+obj-$(CONFIG_SENSORS_INA2XX)    += ina2xx.o
 obj-$(CONFIG_SENSORS_IT87)      += it87.o
 obj-$(CONFIG_SENSORS_JC42)      += jc42.o
 obj-$(CONFIG_SENSORS_JZ4740)    += jz4740-hwmon.o
diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
new file mode 100644
index 000000000000..7f3f4a385729
--- /dev/null
+++ b/drivers/hwmon/ina2xx.c
@@ -0,0 +1,368 @@
+/*
+ * Driver for Texas Instruments INA219, INA226 power monitor chips
+ *
+ * INA219:
+ * Zero Drift Bi-Directional Current/Power Monitor with I2C Interface
+ * Datasheet: http://www.ti.com/product/ina219
+ *
+ * INA226:
+ * Bi-Directional Current/Power Monitor with I2C Interface
+ * Datasheet: http://www.ti.com/product/ina226
+ *
+ * Copyright (C) 2012 Lothar Felten <l-felten@ti.com>
+ * Thanks to Jan Volkering
+ *
+ * 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; version 2 of the License.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+#include <linux/platform_data/ina2xx.h>
+
+/* common register definitions */
+#define INA2XX_CONFIG                   0x00
+#define INA2XX_SHUNT_VOLTAGE            0x01 /* readonly */
+#define INA2XX_BUS_VOLTAGE              0x02 /* readonly */
+#define INA2XX_POWER                    0x03 /* readonly */
+#define INA2XX_CURRENT                  0x04 /* readonly */
+#define INA2XX_CALIBRATION              0x05
+
+/* INA226 register definitions */
+#define INA226_MASK_ENABLE              0x06
+#define INA226_ALERT_LIMIT              0x07
+#define INA226_DIE_ID                   0xFF
+
+
+/* register count */
+#define INA219_REGISTERS                6
+#define INA226_REGISTERS                8
+
+#define INA2XX_MAX_REGISTERS            8
+
+/* settings - depend on use case */
+#define INA219_CONFIG_DEFAULT           0x399F  /* PGA=8 */
+#define INA226_CONFIG_DEFAULT           0x4527  /* averages=16 */
+
+/* worst case is 68.10 ms (~14.6Hz, ina219) */
+#define INA2XX_CONVERSION_RATE          15
+
+enum ina2xx_ids { ina219, ina226 };
+
+struct ina2xx_data {
+        struct device *hwmon_dev;
+
+        struct mutex update_lock;
+        bool valid;
+        unsigned long last_updated;
+
+        int kind;
+        int registers;
+        u16 regs[INA2XX_MAX_REGISTERS];
+};
+
+int ina2xx_read_word(struct i2c_client *client, int reg)
+{
+        int val = i2c_smbus_read_word_data(client, reg);
+        if (unlikely(val < 0)) {
+                dev_dbg(&client->dev,
+                        "Failed to read register: %d\n", reg);
+                return val;
+        }
+        return be16_to_cpu(val);
+}
+
+void ina2xx_write_word(struct i2c_client *client, int reg, int data)
+{
+        i2c_smbus_write_word_data(client, reg, cpu_to_be16(data));
+}
+
+static struct ina2xx_data *ina2xx_update_device(struct device *dev)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        struct ina2xx_data *data = i2c_get_clientdata(client);
+        struct ina2xx_data *ret = data;
+
+        mutex_lock(&data->update_lock);
+
+        if (time_after(jiffies, data->last_updated +
+                       HZ / INA2XX_CONVERSION_RATE) || !data->valid) {
+
+                int i;
+
+                dev_dbg(&client->dev, "Starting ina2xx update\n");
+
+                /* Read all registers */
+                for (i = 0; i < data->registers; i++) {
+                        int rv = ina2xx_read_word(client, i);
+                        if (rv < 0) {
+                                ret = ERR_PTR(rv);
+                                goto abort;
+                        }
+                        data->regs[i] = rv;
+                }
+                data->last_updated = jiffies;
+                data->valid = 1;
+        }
+abort:
+        mutex_unlock(&data->update_lock);
+        return ret;
+}
+
+static int ina219_get_value(struct ina2xx_data *data, u8 reg)
+{
+        /*
+         * calculate exact value for the given register
+         * we assume default power-on reset settings:
+         * bus voltage range 32V
+         * gain = /8
+         * adc 1 & 2 -> conversion time 532uS
+         * mode is continuous shunt and bus
+         * calibration value is INA219_CALIBRATION_VALUE
+         */
+        int val = data->regs[reg];
+