[PATCH] iio: cros_ec_light_prox: add ChromeOS EC Light and Proximity Sensors

From: Enric Balletbo i Serra
Date: Fri Nov 25 2016 - 07:04:18 EST


From: Gwendal Grignou <gwendal@xxxxxxxxxxxx>

Handle Light and Proximity sensors presented by the ChromeOS EC Sensor hub.
Creates an IIO device for each functions.

Signed-off-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
Signed-off-by: Guenter Roeck <groeck@xxxxxxxxxxxx>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
---
drivers/iio/common/cros_ec_sensors/Kconfig | 8 +
drivers/iio/common/cros_ec_sensors/Makefile | 1 +
.../common/cros_ec_sensors/cros_ec_light_prox.c | 278 +++++++++++++++++++++
3 files changed, 287 insertions(+)
create mode 100644 drivers/iio/common/cros_ec_sensors/cros_ec_light_prox.c

diff --git a/drivers/iio/common/cros_ec_sensors/Kconfig b/drivers/iio/common/cros_ec_sensors/Kconfig
index 135f682..4fd0b87 100644
--- a/drivers/iio/common/cros_ec_sensors/Kconfig
+++ b/drivers/iio/common/cros_ec_sensors/Kconfig
@@ -20,3 +20,11 @@ config IIO_CROS_EC_SENSORS
Accelerometers, Gyroscope and Magnetometer that are
presented by the ChromeOS EC Sensor hub.
Creates an IIO device for each functions.
+
+config IIO_CROS_EC_LIGHT_PROX
+ tristate "ChromeOS EC Light and Proximity Sensors"
+ select IIO_CROS_EC_SENSORS_CORE
+ help
+ Module to handle Light and Proximity sensors
+ presented by the ChromeOS EC Sensor hub.
+ Creates an IIO device for each functions.
diff --git a/drivers/iio/common/cros_ec_sensors/Makefile b/drivers/iio/common/cros_ec_sensors/Makefile
index ec716ff..7aaf2a2 100644
--- a/drivers/iio/common/cros_ec_sensors/Makefile
+++ b/drivers/iio/common/cros_ec_sensors/Makefile
@@ -4,3 +4,4 @@

obj-$(CONFIG_IIO_CROS_EC_SENSORS_CORE) += cros_ec_sensors_core.o
obj-$(CONFIG_IIO_CROS_EC_SENSORS) += cros_ec_sensors.o
+obj-$(CONFIG_IIO_CROS_EC_LIGHT_PROX) += cros_ec_light_prox.o
diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_light_prox.c b/drivers/iio/common/cros_ec_sensors/cros_ec_light_prox.c
new file mode 100644
index 0000000..40a34de
--- /dev/null
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_light_prox.c
@@ -0,0 +1,278 @@
+/*
+ * cros_ec_light_prox - Driver for light and prox sensors behing CrosEC.
+ *
+ * Copyright (C) 2016 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/kernel.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/mfd/cros_ec_commands.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+
+#include "cros_ec_sensors_core.h"
+
+/*
+ * We only represent one entry for light or proximity. EC is merging different
+ * light sensors to return the what the eye would see. For proximity, we
+ * currently support only one light source.
+ */
+#define CROS_EC_LIGHT_PROX_MAX_CHANNELS (1 + 1)
+
+/* State data for ec_sensors iio driver. */
+struct cros_ec_sensors_state {
+ /* Shared by all sensors */
+ struct cros_ec_sensors_core_state core;
+
+ struct iio_chan_spec channels[CROS_EC_LIGHT_PROX_MAX_CHANNELS];
+};
+
+static int cros_ec_light_prox_read(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct cros_ec_sensors_state *st = iio_priv(indio_dev);
+ u16 data = 0;
+ s64 val64;
+ int ret;
+ int idx = chan->scan_index;
+
+ mutex_lock(&st->core.cmd_lock);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = cros_ec_sensors_read_cmd(indio_dev, 1 << idx,
+ (s16 *)&data);
+ if (ret < 0)
+ break;
+ *val = data;
+ break;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET;
+ st->core.param.sensor_offset.flags = 0;
+
+ ret = cros_ec_motion_send_host_cmd(&st->core, 0);
+ if (ret < 0)
+ break;
+
+ /* Save values */
+ st->core.calib[0] = st->core.resp->sensor_offset.offset[0];
+
+ *val = st->core.calib[idx];
+ break;
+ case IIO_CHAN_INFO_CALIBSCALE:
+ /*
+ * RANGE is used for calibration
+ * scale is a number x.y, where x is coded on 16bits,
+ * y coded on 16 bits, between 0 and 9999.
+ */
+ st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
+ st->core.param.sensor_range.data = EC_MOTION_SENSE_NO_VALUE;
+
+ ret = cros_ec_motion_send_host_cmd(&st->core, 0);
+ if (ret < 0)
+ break;
+
+ val64 = st->core.resp->sensor_range.ret;
+ *val = val64 >> 16;
+ *val2 = (val64 & 0xffff) * 100;
+ ret = IIO_VAL_INT_PLUS_MICRO;
+ break;
+ case IIO_CHAN_INFO_SCALE:
+ /*
+ * Light: Result in Lux, using calibration multiplier.
+ * Prox: Result in cm.
+ */
+ *val = 1;
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ ret = cros_ec_sensors_core_read(&st->core, chan, val, val2,
+ mask);
+ break;
+ }
+
+ mutex_unlock(&st->core.cmd_lock);
+
+ return ret;
+}
+
+static int cros_ec_light_prox_write(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct cros_ec_sensors_state *st = iio_priv(indio_dev);
+ int ret;
+ int idx = chan->scan_index;
+
+ mutex_lock(&st->core.cmd_lock);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_CALIBBIAS:
+ st->core.calib[idx] = val;
+ /* Send to EC for each axis, even if not complete */
+ st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET;
+ st->core.param.sensor_offset.flags = MOTION_SENSE_SET_OFFSET;
+ st->core.param.sensor_offset.offset[0] =
+ st->core.calib[0];
+ st->core.param.sensor_offset.temp =
+ EC_MOTION_SENSE_INVALID_CALIB_TEMP;
+ ret = cros_ec_motion_send_host_cmd(&st->core, 0);
+ break;
+ case IIO_CHAN_INFO_CALIBSCALE:
+ st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
+ st->core.param.sensor_range.data = (val << 16) | (val2 / 100);
+ ret = cros_ec_motion_send_host_cmd(&st->core, 0);
+ break;
+ default:
+ ret = cros_ec_sensors_core_write(&st->core, chan, val, val2,
+ mask);
+ break;
+ }
+
+ mutex_unlock(&st->core.cmd_lock);
+
+ return ret;
+}
+
+static const struct iio_info ec_sensors_info = {
+ .read_raw = &cros_ec_light_prox_read,
+ .write_raw = &cros_ec_light_prox_write,
+ .driver_module = THIS_MODULE,
+};
+
+static int cros_ec_sensors_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
+ struct cros_ec_device *ec_device;
+ struct iio_dev *indio_dev;
+ struct cros_ec_sensors_state *state;
+ struct iio_chan_spec *channel;
+ int ret;
+
+ if (!ec_dev || !ec_dev->ec_dev) {
+ dev_warn(&pdev->dev, "No CROS EC device found.\n");
+ return -EINVAL;
+ }
+ ec_device = ec_dev->ec_dev;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*state));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ ret = cros_ec_sensors_core_init(pdev, indio_dev, true);
+ if (ret)
+ return ret;
+
+ indio_dev->info = &ec_sensors_info;
+ state = iio_priv(indio_dev);
+ state->core.type = state->core.resp->info.type;
+ state->core.loc = state->core.resp->info.location;
+ channel = state->channels;
+
+ /* Common part */
+ channel->info_mask_separate =
+ BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_CALIBBIAS) |
+ BIT(IIO_CHAN_INFO_CALIBSCALE);
+ channel->info_mask_shared_by_all =
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+ BIT(IIO_CHAN_INFO_FREQUENCY);
+ channel->scan_type.realbits = CROS_EC_SENSOR_BITS;
+ channel->scan_type.storagebits = CROS_EC_SENSOR_BITS;
+ channel->ext_info = cros_ec_sensors_ext_info;
+
+ /* Sensor specific */
+ switch (state->core.type) {
+ case MOTIONSENSE_TYPE_LIGHT:
+ channel->type = IIO_LIGHT;
+ break;
+ case MOTIONSENSE_TYPE_PROX:
+ channel->type = IIO_PROXIMITY;
+ break;
+ default:
+ dev_warn(&pdev->dev, "Unknown motion sensor\n");
+ return -EINVAL;
+ }
+
+ /* Timestamp */
+ channel++;
+ channel->type = IIO_TIMESTAMP;
+ channel->channel = -1;
+ channel->scan_index = 1;
+ channel->scan_type.sign = 's';
+ channel->scan_type.realbits = 64;
+ channel->scan_type.storagebits = 64;
+
+ indio_dev->channels = state->channels;
+
+ indio_dev->num_channels = CROS_EC_LIGHT_PROX_MAX_CHANNELS;
+
+ state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd;
+
+ ret = iio_triggered_buffer_setup(indio_dev, NULL,
+ cros_ec_sensors_capture, NULL);
+ if (ret)
+ return ret;
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ iio_triggered_buffer_cleanup(indio_dev);
+
+ return ret;
+}
+
+static int cros_ec_sensors_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+
+ iio_device_unregister(indio_dev);
+ iio_triggered_buffer_cleanup(indio_dev);
+
+ return 0;
+}
+
+static const struct platform_device_id cros_ec_sensors_ids[] = {
+ {
+ .name = "cros-ec-prox",
+ },
+ {
+ .name = "cros-ec-light",
+ },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(platform, cros_ec_sensors_ids);
+
+static struct platform_driver cros_ec_sensors_platform_driver = {
+ .driver = {
+ .name = "cros-ec-light-prox",
+ },
+ .probe = cros_ec_sensors_probe,
+ .remove = cros_ec_sensors_remove,
+ .id_table = cros_ec_sensors_ids,
+};
+module_platform_driver(cros_ec_sensors_platform_driver);
+
+MODULE_DESCRIPTION("ChromeOS EC light/proximity sensors driver");
+MODULE_LICENSE("GPL v2");
--
2.1.0