iio: add vcnl4000 combined ALS and proximity sensor
authorPeter Meerwald <pmeerw@pmeerw.net>
Tue, 19 Jun 2012 07:58:54 +0000 (09:58 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 20 Jun 2012 23:12:46 +0000 (16:12 -0700)
minimal driver, no IR current control and proximity/event
handling yet

v5:
* checkpatch warnings
* increase msleep() to 20 ms when waiting for data ready as
  measurement/conversion can take up to 100 ms, 1 ms is too short

v4 (address comments by Jonathan Cameron)
* remove SENSORS_ prefix in Kconfig
* change from IIO_INTENSITY to IIO_LIGHT
* move from staging

v3 (address comments by Shubhrajyoti Datta)
* cleanup Kconfig entry
* call I2C read/write functions directly

v2 (address comments by Lars-Peter Clausen and Jonathan Cameron)
* unify code for reading PS and AL data into
  parameterized _measure() function
* limit wait for data to become ready within 20 tries
* drop IIO_LIGHT channel, add SCALE to IIO_INTENSITY
* drop extra string arguments used for logging purpose only

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/iio/light/Kconfig
drivers/iio/light/Makefile
drivers/iio/light/vcnl4000.c [new file with mode: 0644]

index db5618e7d90b6751d5403e960257830139da1269..f3ea90d735b8cdc93c0862167230d64d3677d7e3 100644 (file)
@@ -19,4 +19,15 @@ config SENSORS_LM3533
          light zone through sysfs. A threshold event can be generated on zone
          changes. The ALS-control output values can be set per zone for the
          three current output channels.
+
+config VCNL4000
+       tristate "VCNL4000 combined ALS and proximity sensor"
+       depends on I2C
+       help
+        Say Y here if you want to build a driver for the Vishay VCNL4000
+        combined ambient light and proximity sensor.
+
+        To compile this driver as a module, choose M here: the
+        module will be called vcnl4000.
+
 endmenu
index c1c23a024cd278e928835bd4af07b6318f3a6304..06fa4d3f33ec13f3b8e009b242dcfdbe097c3472 100644 (file)
@@ -3,3 +3,4 @@
 #
 
 obj-$(CONFIG_SENSORS_LM3533)   += lm3533-als.o
+obj-$(CONFIG_VCNL4000)         += vcnl4000.o
diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
new file mode 100644 (file)
index 0000000..e49cb97
--- /dev/null
@@ -0,0 +1,217 @@
+/*
+ * vcnl4000.c - Support for Vishay VCNL4000 combined ambient light and
+ * proximity sensor
+ *
+ * Copyright 2012 Peter Meerwald <pmeerw@pmeerw.net>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * IIO driver for VCNL4000 (7-bit I2C slave address 0x13)
+ *
+ * TODO:
+ *   allow to adjust IR current
+ *   proximity threshold and event handling
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define VCNL4000_DRV_NAME "vcnl4000"
+
+#define VCNL4000_COMMAND       0x80 /* Command register */
+#define VCNL4000_PROD_REV      0x81 /* Product ID and Revision ID */
+#define VCNL4000_LED_CURRENT   0x83 /* IR LED current for proximity mode */
+#define VCNL4000_AL_PARAM      0x84 /* Ambient light parameter register */
+#define VCNL4000_AL_RESULT_HI  0x85 /* Ambient light result register, MSB */
+#define VCNL4000_AL_RESULT_LO  0x86 /* Ambient light result register, LSB */
+#define VCNL4000_PS_RESULT_HI  0x87 /* Proximity result register, MSB */
+#define VCNL4000_PS_RESULT_LO  0x88 /* Proximity result register, LSB */
+#define VCNL4000_PS_MEAS_FREQ  0x89 /* Proximity test signal frequency */
+#define VCNL4000_PS_MOD_ADJ    0x8a /* Proximity modulator timing adjustment */
+
+/* Bit masks for COMMAND register */
+#define VCNL4000_AL_RDY                0x40 /* ALS data ready? */
+#define VCNL4000_PS_RDY                0x20 /* proximity data ready? */
+#define VCNL4000_AL_OD         0x10 /* start on-demand ALS measurement */
+#define VCNL4000_PS_OD         0x08 /* start on-demand proximity measurement */
+
+struct vcnl4000_data {
+       struct i2c_client *client;
+};
+
+static const struct i2c_device_id vcnl4000_id[] = {
+       { "vcnl4000", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, vcnl4000_id);
+
+static int vcnl4000_measure(struct vcnl4000_data *data, u8 req_mask,
+                               u8 rdy_mask, u8 data_reg, int *val)
+{
+       int tries = 20;
+       u16 buf;
+       int ret;
+
+       ret = i2c_smbus_write_byte_data(data->client, VCNL4000_COMMAND,
+                                       req_mask);
+       if (ret < 0)
+               return ret;
+
+       /* wait for data to become ready */
+       while (tries--) {
+               ret = i2c_smbus_read_byte_data(data->client, VCNL4000_COMMAND);
+               if (ret < 0)
+                       return ret;
+               if (ret & rdy_mask)
+                       break;
+               msleep(20); /* measurement takes up to 100 ms */
+       }
+
+       if (tries < 0) {
+               dev_err(&data->client->dev,
+                       "vcnl4000_measure() failed, data not ready\n");
+               return -EIO;
+       }
+
+       ret = i2c_smbus_read_i2c_block_data(data->client,
+               data_reg, sizeof(buf), (u8 *) &buf);
+       if (ret < 0)
+               return ret;
+
+       *val = be16_to_cpu(buf);
+
+       return 0;
+}
+
+static const struct iio_chan_spec vcnl4000_channels[] = {
+       {
+               .type = IIO_LIGHT,
+               .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
+                       IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
+       }, {
+               .type = IIO_PROXIMITY,
+               .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT,
+       }
+};
+
+static int vcnl4000_read_raw(struct iio_dev *indio_dev,
+                               struct iio_chan_spec const *chan,
+                               int *val, int *val2, long mask)
+{
+       int ret = -EINVAL;
+       struct vcnl4000_data *data = iio_priv(indio_dev);
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+               switch (chan->type) {
+               case IIO_LIGHT:
+                       ret = vcnl4000_measure(data,
+                               VCNL4000_AL_OD, VCNL4000_AL_RDY,
+                               VCNL4000_AL_RESULT_HI, val);
+                       if (ret < 0)
+                               return ret;
+                       ret = IIO_VAL_INT;
+                       break;
+               case IIO_PROXIMITY:
+                       ret = vcnl4000_measure(data,
+                               VCNL4000_PS_OD, VCNL4000_PS_RDY,
+                               VCNL4000_PS_RESULT_HI, val);
+                       if (ret < 0)
+                               return ret;
+                       ret = IIO_VAL_INT;
+                       break;
+               default:
+                       break;
+               }
+               break;
+       case IIO_CHAN_INFO_SCALE:
+               if (chan->type == IIO_LIGHT) {
+                       *val = 0;
+                       *val2 = 250000;
+                       ret = IIO_VAL_INT_PLUS_MICRO;
+               }
+               break;
+       default:
+               break;
+       }
+
+       return ret;
+}
+
+static const struct iio_info vcnl4000_info = {
+       .read_raw = vcnl4000_read_raw,
+       .driver_module = THIS_MODULE,
+};
+
+static int __devinit vcnl4000_probe(struct i2c_client *client,
+                                       const struct i2c_device_id *id)
+{
+       struct vcnl4000_data *data;
+       struct iio_dev *indio_dev;
+       int ret;
+
+       indio_dev = iio_device_alloc(sizeof(*data));
+       if (!indio_dev)
+               return -ENOMEM;
+
+       data = iio_priv(indio_dev);
+       i2c_set_clientdata(client, indio_dev);
+       data->client = client;
+
+       ret = i2c_smbus_read_byte_data(data->client, VCNL4000_PROD_REV);
+       if (ret < 0)
+               goto error_free_dev;
+
+       dev_info(&client->dev, "VCNL4000 Ambient light/proximity sensor, Prod %02x, Rev: %02x\n",
+               ret >> 4, ret & 0xf);
+
+       indio_dev->dev.parent = &client->dev;
+       indio_dev->info = &vcnl4000_info;
+       indio_dev->channels = vcnl4000_channels;
+       indio_dev->num_channels = ARRAY_SIZE(vcnl4000_channels);
+       indio_dev->name = VCNL4000_DRV_NAME;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+
+       ret = iio_device_register(indio_dev);
+       if (ret < 0)
+               goto error_free_dev;
+
+       return 0;
+
+error_free_dev:
+       iio_device_free(indio_dev);
+       return ret;
+}
+
+static int __devexit vcnl4000_remove(struct i2c_client *client)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+       iio_device_unregister(indio_dev);
+       iio_device_free(indio_dev);
+
+       return 0;
+}
+
+static struct i2c_driver vcnl4000_driver = {
+       .driver = {
+               .name   = VCNL4000_DRV_NAME,
+               .owner  = THIS_MODULE,
+       },
+       .probe  = vcnl4000_probe,
+       .remove = __devexit_p(vcnl4000_remove),
+       .id_table = vcnl4000_id,
+};
+
+module_i2c_driver(vcnl4000_driver);
+
+MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
+MODULE_DESCRIPTION("Vishay VCNL4000 proximity/ambient light sensor driver");
+MODULE_LICENSE("GPL");