Add tsys02d meas-spec driver support

Support for TSYS02D temperature sensor

Signed-off-by: Ludovic Tancerel <ludovic.tancerel@maplehightech.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-meas-spec b/Documentation/ABI/testing/sysfs-bus-iio-meas-spec
new file mode 100644 (file)
index 0000000..6d47e54
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-meas-spec
@@ -0,0 +1,7 @@
+What:           /sys/bus/iio/devices/iio:deviceX/battery_low
+KernelVersion:  4.1.0
+Contact:        linux-iio@vger.kernel.org
+Description:
+                Reading returns either '1' or '0'. '1' means that the
+                battery level supplied to sensor is below 2.25V.
+                This ABI is available for tsys02d, htu21, ms8607

diff --git a/drivers/iio/temperature/Kconfig b/drivers/iio/temperature/Kconfig
index 35712032b4b994427482a930aee7db65adfc8bca..c4664e5de791577e117a00f2fa276897d343e7a7 100644 (file)
--- a/drivers/iio/temperature/Kconfig
+++ b/drivers/iio/temperature/Kconfig
@@ -34,4 +34,15 @@ config TSYS01
          This driver can also be built as a module. If so, the module will
          be called tsys01.
 
+config TSYS02D
+       tristate "Measurement Specialties TSYS02D temperature sensor"
+       depends on I2C
+       select IIO_MS_SENSORS_I2C
+       help
+         If you say yes here you get support for the Measurement Specialties
+         TSYS02D temperature sensor.
+
+         This driver can also be built as a module. If so, the module will
+         be called tsys02d.
+
 endmenu

diff --git a/drivers/iio/temperature/Makefile b/drivers/iio/temperature/Makefile
index 368a2a2ffe520cc5eb9c9444c08991ca73afc671..02bc79d49b24cf83bb284b36d23bf18f7ebbbfa8 100644 (file)
--- a/drivers/iio/temperature/Makefile
+++ b/drivers/iio/temperature/Makefile
@@ -5,3 +5,4 @@
 obj-$(CONFIG_MLX90614) += mlx90614.o
 obj-$(CONFIG_TMP006) += tmp006.o
 obj-$(CONFIG_TSYS01) += tsys01.o
+obj-$(CONFIG_TSYS02D) += tsys02d.o

diff --git a/drivers/iio/temperature/tsys02d.c b/drivers/iio/temperature/tsys02d.c
new file mode 100644 (file)
index 0000000..4c1fbd5
--- /dev/null
+++ b/drivers/iio/temperature/tsys02d.c
@@ -0,0 +1,191 @@
+/*
+ * tsys02d.c - Support for Measurement-Specialties tsys02d temperature sensor
+ *
+ * Copyright (c) 2015 Measurement-Specialties
+ *
+ * Licensed under the GPL-2.
+ *
+ * (7-bit I2C slave address 0x40)
+ *
+ * Datasheet:
+ *  http://www.meas-spec.com/downloads/Digital_Sensor_TSYS02D.pdf
+ */
+
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/stat.h>
+#include <linux/module.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#include "../common/ms_sensors/ms_sensors_i2c.h"
+
+#define TSYS02D_RESET                          0xFE
+
+static const int tsys02d_samp_freq[4] = { 20, 40, 70, 140 };
+/* String copy of the above const for readability purpose */
+static const char tsys02d_show_samp_freq[] = "20 40 70 140";
+
+static int tsys02d_read_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *channel, int *val,
+                           int *val2, long mask)
+{
+       int ret;
+       s32 temperature;
+       struct ms_ht_dev *dev_data = iio_priv(indio_dev);
+
+       switch (mask) {
+       case IIO_CHAN_INFO_PROCESSED:
+               switch (channel->type) {
+               case IIO_TEMP:  /* in milli °C */
+                       ret = ms_sensors_ht_read_temperature(dev_data,
+                                                            &temperature);
+                       if (ret)
+                               return ret;
+                       *val = temperature;
+
+                       return IIO_VAL_INT;
+               default:
+                       return -EINVAL;
+               }
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               *val = tsys02d_samp_freq[dev_data->res_index];
+
+               return IIO_VAL_INT;
+       default:
+               return -EINVAL;
+       }
+}
+
+static int tsys02d_write_raw(struct iio_dev *indio_dev,
+                            struct iio_chan_spec const *chan,
+                            int val, int val2, long mask)
+{
+       struct ms_ht_dev *dev_data = iio_priv(indio_dev);
+       int i, ret;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               i = ARRAY_SIZE(tsys02d_samp_freq);
+               while (i-- > 0)
+                       if (val == tsys02d_samp_freq[i])
+                               break;
+               if (i < 0)
+                       return -EINVAL;
+               mutex_lock(&dev_data->lock);
+               dev_data->res_index = i;
+               ret = ms_sensors_write_resolution(dev_data, i);
+               mutex_unlock(&dev_data->lock);
+
+               return ret;
+       default:
+               return -EINVAL;
+       }
+}
+
+static const struct iio_chan_spec tsys02d_channels[] = {
+       {
+               .type = IIO_TEMP,
+               .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_PROCESSED),
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+       }
+};
+
+static ssize_t tsys02_read_battery_low(struct device *dev,
+                                      struct device_attribute *attr,
+                                      char *buf)
+{
+       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+       struct ms_ht_dev *dev_data = iio_priv(indio_dev);
+
+       return ms_sensors_show_battery_low(dev_data, buf);
+}
+
+static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(tsys02d_show_samp_freq);
+static IIO_DEVICE_ATTR(battery_low, S_IRUGO,
+                      tsys02_read_battery_low, NULL, 0);
+
+static struct attribute *tsys02d_attributes[] = {
+       &iio_const_attr_sampling_frequency_available.dev_attr.attr,
+       &iio_dev_attr_battery_low.dev_attr.attr,
+       NULL,
+};
+
+static const struct attribute_group tsys02d_attribute_group = {
+       .attrs = tsys02d_attributes,
+};
+
+static const struct iio_info tsys02d_info = {
+       .read_raw = tsys02d_read_raw,
+       .write_raw = tsys02d_write_raw,
+       .attrs = &tsys02d_attribute_group,
+       .driver_module = THIS_MODULE,
+};
+
+static int tsys02d_probe(struct i2c_client *client,
+                        const struct i2c_device_id *id)
+{
+       struct ms_ht_dev *dev_data;
+       struct iio_dev *indio_dev;
+       int ret;
+       u64 serial_number;
+
+       if (!i2c_check_functionality(client->adapter,
+                                    I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
+                                    I2C_FUNC_SMBUS_WRITE_BYTE |
+                                    I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
+               dev_err(&client->dev,
+                       "Adapter does not support some i2c transaction\n");
+               return -ENODEV;
+       }
+
+       indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data));
+       if (!indio_dev)
+               return -ENOMEM;
+
+       dev_data = iio_priv(indio_dev);
+       dev_data->client = client;
+       dev_data->res_index = 0;
+       mutex_init(&dev_data->lock);
+
+       indio_dev->info = &tsys02d_info;
+       indio_dev->name = id->name;
+       indio_dev->dev.parent = &client->dev;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->channels = tsys02d_channels;
+       indio_dev->num_channels = ARRAY_SIZE(tsys02d_channels);
+
+       i2c_set_clientdata(client, indio_dev);
+
+       ret = ms_sensors_reset(client, TSYS02D_RESET, 15000);
+       if (ret)
+               return ret;
+
+       ret = ms_sensors_read_serial(client, &serial_number);
+       if (ret)
+               return ret;
+       dev_info(&client->dev, "Serial number : %llx", serial_number);
+
+       return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static const struct i2c_device_id tsys02d_id[] = {
+       {"tsys02d", 0},
+       {}
+};
+
+static struct i2c_driver tsys02d_driver = {
+       .probe = tsys02d_probe,
+       .id_table = tsys02d_id,
+       .driver = {
+                  .name = "tsys02d",
+                  },
+};
+
+module_i2c_driver(tsys02d_driver);
+
+MODULE_DESCRIPTION("Measurement-Specialties tsys02d temperature driver");
+MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>");
+MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>");
+MODULE_LICENSE("GPL v2");