| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * cros_ec_baro - Driver for barometer sensor behind CrosEC. |
| * |
| * Copyright (C) 2017 Google, Inc |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/iio/buffer.h> |
| #include <linux/iio/common/cros_ec_sensors_core.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/module.h> |
| #include <linux/slab.h> |
| #include <linux/platform_data/cros_ec_commands.h> |
| #include <linux/platform_data/cros_ec_proto.h> |
| #include <linux/platform_device.h> |
| |
| /* |
| * One channel for pressure, the other for timestamp. |
| */ |
| #define CROS_EC_BARO_MAX_CHANNELS (1 + 1) |
| |
| /* State data for ec_sensors iio driver. */ |
| struct cros_ec_baro_state { |
| /* Shared by all sensors */ |
| struct cros_ec_sensors_core_state core; |
| |
| struct iio_chan_spec channels[CROS_EC_BARO_MAX_CHANNELS]; |
| }; |
| |
| static int cros_ec_baro_read(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int *val, int *val2, long mask) |
| { |
| struct cros_ec_baro_state *st = iio_priv(indio_dev); |
| u16 data = 0; |
| 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) |
| break; |
| |
| *val = data; |
| ret = IIO_VAL_INT; |
| break; |
| case IIO_CHAN_INFO_SCALE: |
| 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) |
| break; |
| |
| *val = st->core.resp->sensor_range.ret; |
| |
| /* scale * in_pressure_raw --> kPa */ |
| *val2 = 10 << CROS_EC_SENSOR_BITS; |
| ret = IIO_VAL_FRACTIONAL; |
| 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_baro_write(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int val, int val2, long mask) |
| { |
| struct cros_ec_baro_state *st = iio_priv(indio_dev); |
| int ret = 0; |
| |
| mutex_lock(&st->core.cmd_lock); |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_SCALE: |
| st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE; |
| st->core.param.sensor_range.data = val; |
| |
| /* Always roundup, so caller gets at least what it asks for. */ |
| st->core.param.sensor_range.roundup = 1; |
| |
| ret = cros_ec_motion_send_host_cmd(&st->core, 0); |
| if (ret == 0) { |
| st->core.range_updated = true; |
| st->core.curr_range = val; |
| } |
| 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 cros_ec_baro_info = { |
| .read_raw = &cros_ec_baro_read, |
| .write_raw = &cros_ec_baro_write, |
| .read_avail = &cros_ec_sensors_core_read_avail, |
| }; |
| |
| static int cros_ec_baro_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent); |
| struct iio_dev *indio_dev; |
| struct cros_ec_baro_state *state; |
| struct iio_chan_spec *channel; |
| int ret; |
| |
| if (!ec_dev || !ec_dev->ec_dev) { |
| dev_warn(dev, "No CROS EC device found.\n"); |
| return -EINVAL; |
| } |
| |
| indio_dev = devm_iio_device_alloc(dev, sizeof(*state)); |
| if (!indio_dev) |
| return -ENOMEM; |
| |
| ret = cros_ec_sensors_core_init(pdev, indio_dev, true, |
| cros_ec_sensors_capture, |
| cros_ec_sensors_push_data); |
| if (ret) |
| return ret; |
| |
| iio_buffer_set_attrs(indio_dev->buffer, cros_ec_sensor_fifo_attributes); |
| |
| indio_dev->info = &cros_ec_baro_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); |
| channel->info_mask_shared_by_all = |
| BIT(IIO_CHAN_INFO_SCALE) | |
| BIT(IIO_CHAN_INFO_SAMP_FREQ); |
| channel->info_mask_shared_by_all_available = |
| BIT(IIO_CHAN_INFO_SAMP_FREQ); |
| channel->scan_type.realbits = CROS_EC_SENSOR_BITS; |
| channel->scan_type.storagebits = CROS_EC_SENSOR_BITS; |
| channel->scan_type.shift = 0; |
| channel->scan_index = 0; |
| channel->ext_info = cros_ec_sensors_ext_info; |
| channel->scan_type.sign = 'u'; |
| |
| /* Sensor specific */ |
| switch (state->core.type) { |
| case MOTIONSENSE_TYPE_BARO: |
| channel->type = IIO_PRESSURE; |
| break; |
| default: |
| dev_warn(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_BARO_MAX_CHANNELS; |
| |
| state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd; |
| |
| return devm_iio_device_register(dev, indio_dev); |
| } |
| |
| static const struct platform_device_id cros_ec_baro_ids[] = { |
| { |
| .name = "cros-ec-baro", |
| }, |
| { /* sentinel */ } |
| }; |
| MODULE_DEVICE_TABLE(platform, cros_ec_baro_ids); |
| |
| static struct platform_driver cros_ec_baro_platform_driver = { |
| .driver = { |
| .name = "cros-ec-baro", |
| .pm = &cros_ec_sensors_pm_ops, |
| }, |
| .probe = cros_ec_baro_probe, |
| .id_table = cros_ec_baro_ids, |
| }; |
| module_platform_driver(cros_ec_baro_platform_driver); |
| |
| MODULE_DESCRIPTION("ChromeOS EC barometer sensor driver"); |
| MODULE_LICENSE("GPL v2"); |