137aa055cSEnric Balletbo i Serra // SPDX-License-Identifier: GPL-2.0 2c14dca07SEnric Balletbo i Serra /* 3c14dca07SEnric Balletbo i Serra * cros_ec_sensors - Driver for Chrome OS Embedded Controller sensors. 4c14dca07SEnric Balletbo i Serra * 5c14dca07SEnric Balletbo i Serra * Copyright (C) 2016 Google, Inc 6c14dca07SEnric Balletbo i Serra * 7c14dca07SEnric Balletbo i Serra * This driver uses the cros-ec interface to communicate with the Chrome OS 8c14dca07SEnric Balletbo i Serra * EC about sensors data. Data access is presented through iio sysfs. 9c14dca07SEnric Balletbo i Serra */ 10c14dca07SEnric Balletbo i Serra 11c14dca07SEnric Balletbo i Serra #include <linux/device.h> 12c14dca07SEnric Balletbo i Serra #include <linux/iio/buffer.h> 135a0b8cb4SGwendal Grignou #include <linux/iio/common/cros_ec_sensors_core.h> 14c14dca07SEnric Balletbo i Serra #include <linux/iio/iio.h> 15c14dca07SEnric Balletbo i Serra #include <linux/iio/kfifo_buf.h> 16c14dca07SEnric Balletbo i Serra #include <linux/iio/trigger_consumer.h> 17c14dca07SEnric Balletbo i Serra #include <linux/iio/triggered_buffer.h> 18c14dca07SEnric Balletbo i Serra #include <linux/kernel.h> 19c14dca07SEnric Balletbo i Serra #include <linux/mfd/cros_ec.h> 20c14dca07SEnric Balletbo i Serra #include <linux/module.h> 21840d9f13SEnric Balletbo i Serra #include <linux/platform_data/cros_ec_commands.h> 22840d9f13SEnric Balletbo i Serra #include <linux/platform_data/cros_ec_proto.h> 23c14dca07SEnric Balletbo i Serra #include <linux/platform_device.h> 24c14dca07SEnric Balletbo i Serra #include <linux/slab.h> 25c14dca07SEnric Balletbo i Serra 26c14dca07SEnric Balletbo i Serra #define CROS_EC_SENSORS_MAX_CHANNELS 4 27c14dca07SEnric Balletbo i Serra 28c14dca07SEnric Balletbo i Serra /* State data for ec_sensors iio driver. */ 29c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_state { 30c14dca07SEnric Balletbo i Serra /* Shared by all sensors */ 31c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_core_state core; 32c14dca07SEnric Balletbo i Serra 33c14dca07SEnric Balletbo i Serra struct iio_chan_spec channels[CROS_EC_SENSORS_MAX_CHANNELS]; 34c14dca07SEnric Balletbo i Serra }; 35c14dca07SEnric Balletbo i Serra 36c14dca07SEnric Balletbo i Serra static int cros_ec_sensors_read(struct iio_dev *indio_dev, 37c14dca07SEnric Balletbo i Serra struct iio_chan_spec const *chan, 38c14dca07SEnric Balletbo i Serra int *val, int *val2, long mask) 39c14dca07SEnric Balletbo i Serra { 40c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_state *st = iio_priv(indio_dev); 41c14dca07SEnric Balletbo i Serra s16 data = 0; 42c14dca07SEnric Balletbo i Serra s64 val64; 43c14dca07SEnric Balletbo i Serra int i; 445668bfddSEnric Balletbo i Serra int ret; 45c14dca07SEnric Balletbo i Serra int idx = chan->scan_index; 46c14dca07SEnric Balletbo i Serra 47c14dca07SEnric Balletbo i Serra mutex_lock(&st->core.cmd_lock); 48c14dca07SEnric Balletbo i Serra 49c14dca07SEnric Balletbo i Serra switch (mask) { 50c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_RAW: 51c14dca07SEnric Balletbo i Serra ret = st->core.read_ec_sensors_data(indio_dev, 1 << idx, &data); 52c14dca07SEnric Balletbo i Serra if (ret < 0) 53c14dca07SEnric Balletbo i Serra break; 54a096926eSEnric Balletbo i Serra ret = IIO_VAL_INT; 55c14dca07SEnric Balletbo i Serra *val = data; 56c14dca07SEnric Balletbo i Serra break; 57c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_CALIBBIAS: 58c14dca07SEnric Balletbo i Serra st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET; 59c14dca07SEnric Balletbo i Serra st->core.param.sensor_offset.flags = 0; 60c14dca07SEnric Balletbo i Serra 61c14dca07SEnric Balletbo i Serra ret = cros_ec_motion_send_host_cmd(&st->core, 0); 62c14dca07SEnric Balletbo i Serra if (ret < 0) 63c14dca07SEnric Balletbo i Serra break; 64c14dca07SEnric Balletbo i Serra 65c14dca07SEnric Balletbo i Serra /* Save values */ 66c14dca07SEnric Balletbo i Serra for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++) 67c14dca07SEnric Balletbo i Serra st->core.calib[i] = 68c14dca07SEnric Balletbo i Serra st->core.resp->sensor_offset.offset[i]; 69a096926eSEnric Balletbo i Serra ret = IIO_VAL_INT; 70c14dca07SEnric Balletbo i Serra *val = st->core.calib[idx]; 71c14dca07SEnric Balletbo i Serra break; 72c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_SCALE: 73c14dca07SEnric Balletbo i Serra st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE; 74c14dca07SEnric Balletbo i Serra st->core.param.sensor_range.data = EC_MOTION_SENSE_NO_VALUE; 75c14dca07SEnric Balletbo i Serra 76c14dca07SEnric Balletbo i Serra ret = cros_ec_motion_send_host_cmd(&st->core, 0); 77c14dca07SEnric Balletbo i Serra if (ret < 0) 78c14dca07SEnric Balletbo i Serra break; 79c14dca07SEnric Balletbo i Serra 80c14dca07SEnric Balletbo i Serra val64 = st->core.resp->sensor_range.ret; 81c14dca07SEnric Balletbo i Serra switch (st->core.type) { 82c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_ACCEL: 83c14dca07SEnric Balletbo i Serra /* 84c14dca07SEnric Balletbo i Serra * EC returns data in g, iio exepects m/s^2. 85c14dca07SEnric Balletbo i Serra * Do not use IIO_G_TO_M_S_2 to avoid precision loss. 86c14dca07SEnric Balletbo i Serra */ 87c14dca07SEnric Balletbo i Serra *val = div_s64(val64 * 980665, 10); 88c14dca07SEnric Balletbo i Serra *val2 = 10000 << (CROS_EC_SENSOR_BITS - 1); 89c14dca07SEnric Balletbo i Serra ret = IIO_VAL_FRACTIONAL; 90c14dca07SEnric Balletbo i Serra break; 91c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_GYRO: 92c14dca07SEnric Balletbo i Serra /* 93c14dca07SEnric Balletbo i Serra * EC returns data in dps, iio expects rad/s. 94c14dca07SEnric Balletbo i Serra * Do not use IIO_DEGREE_TO_RAD to avoid precision 95c14dca07SEnric Balletbo i Serra * loss. Round to the nearest integer. 96c14dca07SEnric Balletbo i Serra */ 973d02d708SGwendal Grignou *val = 0; 983d02d708SGwendal Grignou *val2 = div_s64(val64 * 3141592653ULL, 993d02d708SGwendal Grignou 180 << (CROS_EC_SENSOR_BITS - 1)); 1003d02d708SGwendal Grignou ret = IIO_VAL_INT_PLUS_NANO; 101c14dca07SEnric Balletbo i Serra break; 102c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_MAG: 103c14dca07SEnric Balletbo i Serra /* 104c14dca07SEnric Balletbo i Serra * EC returns data in 16LSB / uT, 105c14dca07SEnric Balletbo i Serra * iio expects Gauss 106c14dca07SEnric Balletbo i Serra */ 107c14dca07SEnric Balletbo i Serra *val = val64; 108c14dca07SEnric Balletbo i Serra *val2 = 100 << (CROS_EC_SENSOR_BITS - 1); 109c14dca07SEnric Balletbo i Serra ret = IIO_VAL_FRACTIONAL; 110c14dca07SEnric Balletbo i Serra break; 111c14dca07SEnric Balletbo i Serra default: 112c14dca07SEnric Balletbo i Serra ret = -EINVAL; 113c14dca07SEnric Balletbo i Serra } 114c14dca07SEnric Balletbo i Serra break; 115c14dca07SEnric Balletbo i Serra default: 116c14dca07SEnric Balletbo i Serra ret = cros_ec_sensors_core_read(&st->core, chan, val, val2, 117c14dca07SEnric Balletbo i Serra mask); 118c14dca07SEnric Balletbo i Serra break; 119c14dca07SEnric Balletbo i Serra } 120c14dca07SEnric Balletbo i Serra mutex_unlock(&st->core.cmd_lock); 121c14dca07SEnric Balletbo i Serra 122c14dca07SEnric Balletbo i Serra return ret; 123c14dca07SEnric Balletbo i Serra } 124c14dca07SEnric Balletbo i Serra 125c14dca07SEnric Balletbo i Serra static int cros_ec_sensors_write(struct iio_dev *indio_dev, 126c14dca07SEnric Balletbo i Serra struct iio_chan_spec const *chan, 127c14dca07SEnric Balletbo i Serra int val, int val2, long mask) 128c14dca07SEnric Balletbo i Serra { 129c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_state *st = iio_priv(indio_dev); 130c14dca07SEnric Balletbo i Serra int i; 1315668bfddSEnric Balletbo i Serra int ret; 132c14dca07SEnric Balletbo i Serra int idx = chan->scan_index; 133c14dca07SEnric Balletbo i Serra 134c14dca07SEnric Balletbo i Serra mutex_lock(&st->core.cmd_lock); 135c14dca07SEnric Balletbo i Serra 136c14dca07SEnric Balletbo i Serra switch (mask) { 137c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_CALIBBIAS: 138c14dca07SEnric Balletbo i Serra st->core.calib[idx] = val; 139c14dca07SEnric Balletbo i Serra 140c14dca07SEnric Balletbo i Serra /* Send to EC for each axis, even if not complete */ 141c14dca07SEnric Balletbo i Serra st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET; 142c14dca07SEnric Balletbo i Serra st->core.param.sensor_offset.flags = 143c14dca07SEnric Balletbo i Serra MOTION_SENSE_SET_OFFSET; 144c14dca07SEnric Balletbo i Serra for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++) 145c14dca07SEnric Balletbo i Serra st->core.param.sensor_offset.offset[i] = 146c14dca07SEnric Balletbo i Serra st->core.calib[i]; 147c14dca07SEnric Balletbo i Serra st->core.param.sensor_offset.temp = 148c14dca07SEnric Balletbo i Serra EC_MOTION_SENSE_INVALID_CALIB_TEMP; 149c14dca07SEnric Balletbo i Serra 150c14dca07SEnric Balletbo i Serra ret = cros_ec_motion_send_host_cmd(&st->core, 0); 151c14dca07SEnric Balletbo i Serra break; 152c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_SCALE: 153c14dca07SEnric Balletbo i Serra if (st->core.type == MOTIONSENSE_TYPE_MAG) { 154c14dca07SEnric Balletbo i Serra ret = -EINVAL; 155c14dca07SEnric Balletbo i Serra break; 156c14dca07SEnric Balletbo i Serra } 157c14dca07SEnric Balletbo i Serra st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE; 158c14dca07SEnric Balletbo i Serra st->core.param.sensor_range.data = val; 159c14dca07SEnric Balletbo i Serra 160c14dca07SEnric Balletbo i Serra /* Always roundup, so caller gets at least what it asks for. */ 161c14dca07SEnric Balletbo i Serra st->core.param.sensor_range.roundup = 1; 162c14dca07SEnric Balletbo i Serra 163c14dca07SEnric Balletbo i Serra ret = cros_ec_motion_send_host_cmd(&st->core, 0); 164c14dca07SEnric Balletbo i Serra break; 165c14dca07SEnric Balletbo i Serra default: 166c14dca07SEnric Balletbo i Serra ret = cros_ec_sensors_core_write( 167c14dca07SEnric Balletbo i Serra &st->core, chan, val, val2, mask); 168c14dca07SEnric Balletbo i Serra break; 169c14dca07SEnric Balletbo i Serra } 170c14dca07SEnric Balletbo i Serra 171c14dca07SEnric Balletbo i Serra mutex_unlock(&st->core.cmd_lock); 172c14dca07SEnric Balletbo i Serra 173c14dca07SEnric Balletbo i Serra return ret; 174c14dca07SEnric Balletbo i Serra } 175c14dca07SEnric Balletbo i Serra 176c14dca07SEnric Balletbo i Serra static const struct iio_info ec_sensors_info = { 177c14dca07SEnric Balletbo i Serra .read_raw = &cros_ec_sensors_read, 178c14dca07SEnric Balletbo i Serra .write_raw = &cros_ec_sensors_write, 179c14dca07SEnric Balletbo i Serra }; 180c14dca07SEnric Balletbo i Serra 181c14dca07SEnric Balletbo i Serra static int cros_ec_sensors_probe(struct platform_device *pdev) 182c14dca07SEnric Balletbo i Serra { 183c14dca07SEnric Balletbo i Serra struct device *dev = &pdev->dev; 184c14dca07SEnric Balletbo i Serra struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent); 185c14dca07SEnric Balletbo i Serra struct iio_dev *indio_dev; 186c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_state *state; 187c14dca07SEnric Balletbo i Serra struct iio_chan_spec *channel; 188c14dca07SEnric Balletbo i Serra int ret, i; 189c14dca07SEnric Balletbo i Serra 190c14dca07SEnric Balletbo i Serra if (!ec_dev || !ec_dev->ec_dev) { 191c14dca07SEnric Balletbo i Serra dev_warn(&pdev->dev, "No CROS EC device found.\n"); 192c14dca07SEnric Balletbo i Serra return -EINVAL; 193c14dca07SEnric Balletbo i Serra } 194c14dca07SEnric Balletbo i Serra 195c14dca07SEnric Balletbo i Serra indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*state)); 196c14dca07SEnric Balletbo i Serra if (!indio_dev) 197c14dca07SEnric Balletbo i Serra return -ENOMEM; 198c14dca07SEnric Balletbo i Serra 199c14dca07SEnric Balletbo i Serra ret = cros_ec_sensors_core_init(pdev, indio_dev, true); 200c14dca07SEnric Balletbo i Serra if (ret) 201c14dca07SEnric Balletbo i Serra return ret; 202c14dca07SEnric Balletbo i Serra 203c14dca07SEnric Balletbo i Serra indio_dev->info = &ec_sensors_info; 204c14dca07SEnric Balletbo i Serra state = iio_priv(indio_dev); 205c14dca07SEnric Balletbo i Serra for (channel = state->channels, i = CROS_EC_SENSOR_X; 206c14dca07SEnric Balletbo i Serra i < CROS_EC_SENSOR_MAX_AXIS; i++, channel++) { 207c14dca07SEnric Balletbo i Serra /* Common part */ 208c14dca07SEnric Balletbo i Serra channel->info_mask_separate = 209c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_RAW) | 210c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_CALIBBIAS); 211c14dca07SEnric Balletbo i Serra channel->info_mask_shared_by_all = 212c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_SCALE) | 213c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_FREQUENCY) | 214c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_SAMP_FREQ); 215c14dca07SEnric Balletbo i Serra channel->scan_type.realbits = CROS_EC_SENSOR_BITS; 216c14dca07SEnric Balletbo i Serra channel->scan_type.storagebits = CROS_EC_SENSOR_BITS; 217c14dca07SEnric Balletbo i Serra channel->scan_index = i; 218c14dca07SEnric Balletbo i Serra channel->ext_info = cros_ec_sensors_ext_info; 219c14dca07SEnric Balletbo i Serra channel->modified = 1; 220c14dca07SEnric Balletbo i Serra channel->channel2 = IIO_MOD_X + i; 221c14dca07SEnric Balletbo i Serra channel->scan_type.sign = 's'; 222c14dca07SEnric Balletbo i Serra 223c14dca07SEnric Balletbo i Serra /* Sensor specific */ 224c14dca07SEnric Balletbo i Serra switch (state->core.type) { 225c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_ACCEL: 226c14dca07SEnric Balletbo i Serra channel->type = IIO_ACCEL; 227c14dca07SEnric Balletbo i Serra break; 228c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_GYRO: 229c14dca07SEnric Balletbo i Serra channel->type = IIO_ANGL_VEL; 230c14dca07SEnric Balletbo i Serra break; 231c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_MAG: 232c14dca07SEnric Balletbo i Serra channel->type = IIO_MAGN; 233c14dca07SEnric Balletbo i Serra break; 234c14dca07SEnric Balletbo i Serra default: 235c14dca07SEnric Balletbo i Serra dev_err(&pdev->dev, "Unknown motion sensor\n"); 236c14dca07SEnric Balletbo i Serra return -EINVAL; 237c14dca07SEnric Balletbo i Serra } 238c14dca07SEnric Balletbo i Serra } 239c14dca07SEnric Balletbo i Serra 240c14dca07SEnric Balletbo i Serra /* Timestamp */ 241c14dca07SEnric Balletbo i Serra channel->type = IIO_TIMESTAMP; 242c14dca07SEnric Balletbo i Serra channel->channel = -1; 243c14dca07SEnric Balletbo i Serra channel->scan_index = CROS_EC_SENSOR_MAX_AXIS; 244c14dca07SEnric Balletbo i Serra channel->scan_type.sign = 's'; 245c14dca07SEnric Balletbo i Serra channel->scan_type.realbits = 64; 246c14dca07SEnric Balletbo i Serra channel->scan_type.storagebits = 64; 247c14dca07SEnric Balletbo i Serra 248c14dca07SEnric Balletbo i Serra indio_dev->channels = state->channels; 249c14dca07SEnric Balletbo i Serra indio_dev->num_channels = CROS_EC_SENSORS_MAX_CHANNELS; 250c14dca07SEnric Balletbo i Serra 251c14dca07SEnric Balletbo i Serra /* There is only enough room for accel and gyro in the io space */ 252c14dca07SEnric Balletbo i Serra if ((state->core.ec->cmd_readmem != NULL) && 253c14dca07SEnric Balletbo i Serra (state->core.type != MOTIONSENSE_TYPE_MAG)) 254c14dca07SEnric Balletbo i Serra state->core.read_ec_sensors_data = cros_ec_sensors_read_lpc; 255c14dca07SEnric Balletbo i Serra else 256c14dca07SEnric Balletbo i Serra state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd; 257c14dca07SEnric Balletbo i Serra 258754434c4SEnric Balletbo i Serra ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, 259c14dca07SEnric Balletbo i Serra cros_ec_sensors_capture, NULL); 260c14dca07SEnric Balletbo i Serra if (ret) 261c14dca07SEnric Balletbo i Serra return ret; 262c14dca07SEnric Balletbo i Serra 263754434c4SEnric Balletbo i Serra return devm_iio_device_register(dev, indio_dev); 264c14dca07SEnric Balletbo i Serra } 265c14dca07SEnric Balletbo i Serra 266c14dca07SEnric Balletbo i Serra static const struct platform_device_id cros_ec_sensors_ids[] = { 267c14dca07SEnric Balletbo i Serra { 268c14dca07SEnric Balletbo i Serra .name = "cros-ec-accel", 269c14dca07SEnric Balletbo i Serra }, 270c14dca07SEnric Balletbo i Serra { 271c14dca07SEnric Balletbo i Serra .name = "cros-ec-gyro", 272c14dca07SEnric Balletbo i Serra }, 273c14dca07SEnric Balletbo i Serra { 274c14dca07SEnric Balletbo i Serra .name = "cros-ec-mag", 275c14dca07SEnric Balletbo i Serra }, 276c14dca07SEnric Balletbo i Serra { /* sentinel */ } 277c14dca07SEnric Balletbo i Serra }; 278c14dca07SEnric Balletbo i Serra MODULE_DEVICE_TABLE(platform, cros_ec_sensors_ids); 279c14dca07SEnric Balletbo i Serra 280c14dca07SEnric Balletbo i Serra static struct platform_driver cros_ec_sensors_platform_driver = { 281c14dca07SEnric Balletbo i Serra .driver = { 282c14dca07SEnric Balletbo i Serra .name = "cros-ec-sensors", 2830dad1eceSGwendal Grignou .pm = &cros_ec_sensors_pm_ops, 284c14dca07SEnric Balletbo i Serra }, 285c14dca07SEnric Balletbo i Serra .probe = cros_ec_sensors_probe, 286c14dca07SEnric Balletbo i Serra .id_table = cros_ec_sensors_ids, 287c14dca07SEnric Balletbo i Serra }; 288c14dca07SEnric Balletbo i Serra module_platform_driver(cros_ec_sensors_platform_driver); 289c14dca07SEnric Balletbo i Serra 290c14dca07SEnric Balletbo i Serra MODULE_DESCRIPTION("ChromeOS EC 3-axis sensors driver"); 291c14dca07SEnric Balletbo i Serra MODULE_LICENSE("GPL v2"); 292