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/mfd/cros_ec_commands.h> 21c14dca07SEnric Balletbo i Serra #include <linux/module.h> 22c14dca07SEnric Balletbo i Serra #include <linux/platform_device.h> 23c14dca07SEnric Balletbo i Serra #include <linux/slab.h> 24c14dca07SEnric Balletbo i Serra 25c14dca07SEnric Balletbo i Serra #define CROS_EC_SENSORS_MAX_CHANNELS 4 26c14dca07SEnric Balletbo i Serra 27c14dca07SEnric Balletbo i Serra /* State data for ec_sensors iio driver. */ 28c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_state { 29c14dca07SEnric Balletbo i Serra /* Shared by all sensors */ 30c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_core_state core; 31c14dca07SEnric Balletbo i Serra 32c14dca07SEnric Balletbo i Serra struct iio_chan_spec channels[CROS_EC_SENSORS_MAX_CHANNELS]; 33c14dca07SEnric Balletbo i Serra }; 34c14dca07SEnric Balletbo i Serra 35c14dca07SEnric Balletbo i Serra static int cros_ec_sensors_read(struct iio_dev *indio_dev, 36c14dca07SEnric Balletbo i Serra struct iio_chan_spec const *chan, 37c14dca07SEnric Balletbo i Serra int *val, int *val2, long mask) 38c14dca07SEnric Balletbo i Serra { 39c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_state *st = iio_priv(indio_dev); 40c14dca07SEnric Balletbo i Serra s16 data = 0; 41c14dca07SEnric Balletbo i Serra s64 val64; 42c14dca07SEnric Balletbo i Serra int i; 435668bfddSEnric Balletbo i Serra int ret; 44c14dca07SEnric Balletbo i Serra int idx = chan->scan_index; 45c14dca07SEnric Balletbo i Serra 46c14dca07SEnric Balletbo i Serra mutex_lock(&st->core.cmd_lock); 47c14dca07SEnric Balletbo i Serra 48c14dca07SEnric Balletbo i Serra switch (mask) { 49c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_RAW: 50c14dca07SEnric Balletbo i Serra ret = st->core.read_ec_sensors_data(indio_dev, 1 << idx, &data); 51c14dca07SEnric Balletbo i Serra if (ret < 0) 52c14dca07SEnric Balletbo i Serra break; 53a096926eSEnric Balletbo i Serra ret = IIO_VAL_INT; 54c14dca07SEnric Balletbo i Serra *val = data; 55c14dca07SEnric Balletbo i Serra break; 56c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_CALIBBIAS: 57c14dca07SEnric Balletbo i Serra st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET; 58c14dca07SEnric Balletbo i Serra st->core.param.sensor_offset.flags = 0; 59c14dca07SEnric Balletbo i Serra 60c14dca07SEnric Balletbo i Serra ret = cros_ec_motion_send_host_cmd(&st->core, 0); 61c14dca07SEnric Balletbo i Serra if (ret < 0) 62c14dca07SEnric Balletbo i Serra break; 63c14dca07SEnric Balletbo i Serra 64c14dca07SEnric Balletbo i Serra /* Save values */ 65c14dca07SEnric Balletbo i Serra for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++) 66c14dca07SEnric Balletbo i Serra st->core.calib[i] = 67c14dca07SEnric Balletbo i Serra st->core.resp->sensor_offset.offset[i]; 68a096926eSEnric Balletbo i Serra ret = IIO_VAL_INT; 69c14dca07SEnric Balletbo i Serra *val = st->core.calib[idx]; 70c14dca07SEnric Balletbo i Serra break; 71c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_SCALE: 72c14dca07SEnric Balletbo i Serra st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE; 73c14dca07SEnric Balletbo i Serra st->core.param.sensor_range.data = EC_MOTION_SENSE_NO_VALUE; 74c14dca07SEnric Balletbo i Serra 75c14dca07SEnric Balletbo i Serra ret = cros_ec_motion_send_host_cmd(&st->core, 0); 76c14dca07SEnric Balletbo i Serra if (ret < 0) 77c14dca07SEnric Balletbo i Serra break; 78c14dca07SEnric Balletbo i Serra 79c14dca07SEnric Balletbo i Serra val64 = st->core.resp->sensor_range.ret; 80c14dca07SEnric Balletbo i Serra switch (st->core.type) { 81c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_ACCEL: 82c14dca07SEnric Balletbo i Serra /* 83c14dca07SEnric Balletbo i Serra * EC returns data in g, iio exepects m/s^2. 84c14dca07SEnric Balletbo i Serra * Do not use IIO_G_TO_M_S_2 to avoid precision loss. 85c14dca07SEnric Balletbo i Serra */ 86c14dca07SEnric Balletbo i Serra *val = div_s64(val64 * 980665, 10); 87c14dca07SEnric Balletbo i Serra *val2 = 10000 << (CROS_EC_SENSOR_BITS - 1); 88c14dca07SEnric Balletbo i Serra ret = IIO_VAL_FRACTIONAL; 89c14dca07SEnric Balletbo i Serra break; 90c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_GYRO: 91c14dca07SEnric Balletbo i Serra /* 92c14dca07SEnric Balletbo i Serra * EC returns data in dps, iio expects rad/s. 93c14dca07SEnric Balletbo i Serra * Do not use IIO_DEGREE_TO_RAD to avoid precision 94c14dca07SEnric Balletbo i Serra * loss. Round to the nearest integer. 95c14dca07SEnric Balletbo i Serra */ 96c14dca07SEnric Balletbo i Serra *val = div_s64(val64 * 314159 + 9000000ULL, 1000); 97c14dca07SEnric Balletbo i Serra *val2 = 18000 << (CROS_EC_SENSOR_BITS - 1); 98c14dca07SEnric Balletbo i Serra ret = IIO_VAL_FRACTIONAL; 99c14dca07SEnric Balletbo i Serra break; 100c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_MAG: 101c14dca07SEnric Balletbo i Serra /* 102c14dca07SEnric Balletbo i Serra * EC returns data in 16LSB / uT, 103c14dca07SEnric Balletbo i Serra * iio expects Gauss 104c14dca07SEnric Balletbo i Serra */ 105c14dca07SEnric Balletbo i Serra *val = val64; 106c14dca07SEnric Balletbo i Serra *val2 = 100 << (CROS_EC_SENSOR_BITS - 1); 107c14dca07SEnric Balletbo i Serra ret = IIO_VAL_FRACTIONAL; 108c14dca07SEnric Balletbo i Serra break; 109c14dca07SEnric Balletbo i Serra default: 110c14dca07SEnric Balletbo i Serra ret = -EINVAL; 111c14dca07SEnric Balletbo i Serra } 112c14dca07SEnric Balletbo i Serra break; 113c14dca07SEnric Balletbo i Serra default: 114c14dca07SEnric Balletbo i Serra ret = cros_ec_sensors_core_read(&st->core, chan, val, val2, 115c14dca07SEnric Balletbo i Serra mask); 116c14dca07SEnric Balletbo i Serra break; 117c14dca07SEnric Balletbo i Serra } 118c14dca07SEnric Balletbo i Serra mutex_unlock(&st->core.cmd_lock); 119c14dca07SEnric Balletbo i Serra 120c14dca07SEnric Balletbo i Serra return ret; 121c14dca07SEnric Balletbo i Serra } 122c14dca07SEnric Balletbo i Serra 123c14dca07SEnric Balletbo i Serra static int cros_ec_sensors_write(struct iio_dev *indio_dev, 124c14dca07SEnric Balletbo i Serra struct iio_chan_spec const *chan, 125c14dca07SEnric Balletbo i Serra int val, int val2, long mask) 126c14dca07SEnric Balletbo i Serra { 127c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_state *st = iio_priv(indio_dev); 128c14dca07SEnric Balletbo i Serra int i; 1295668bfddSEnric Balletbo i Serra int ret; 130c14dca07SEnric Balletbo i Serra int idx = chan->scan_index; 131c14dca07SEnric Balletbo i Serra 132c14dca07SEnric Balletbo i Serra mutex_lock(&st->core.cmd_lock); 133c14dca07SEnric Balletbo i Serra 134c14dca07SEnric Balletbo i Serra switch (mask) { 135c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_CALIBBIAS: 136c14dca07SEnric Balletbo i Serra st->core.calib[idx] = val; 137c14dca07SEnric Balletbo i Serra 138c14dca07SEnric Balletbo i Serra /* Send to EC for each axis, even if not complete */ 139c14dca07SEnric Balletbo i Serra st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET; 140c14dca07SEnric Balletbo i Serra st->core.param.sensor_offset.flags = 141c14dca07SEnric Balletbo i Serra MOTION_SENSE_SET_OFFSET; 142c14dca07SEnric Balletbo i Serra for (i = CROS_EC_SENSOR_X; i < CROS_EC_SENSOR_MAX_AXIS; i++) 143c14dca07SEnric Balletbo i Serra st->core.param.sensor_offset.offset[i] = 144c14dca07SEnric Balletbo i Serra st->core.calib[i]; 145c14dca07SEnric Balletbo i Serra st->core.param.sensor_offset.temp = 146c14dca07SEnric Balletbo i Serra EC_MOTION_SENSE_INVALID_CALIB_TEMP; 147c14dca07SEnric Balletbo i Serra 148c14dca07SEnric Balletbo i Serra ret = cros_ec_motion_send_host_cmd(&st->core, 0); 149c14dca07SEnric Balletbo i Serra break; 150c14dca07SEnric Balletbo i Serra case IIO_CHAN_INFO_SCALE: 151c14dca07SEnric Balletbo i Serra if (st->core.type == MOTIONSENSE_TYPE_MAG) { 152c14dca07SEnric Balletbo i Serra ret = -EINVAL; 153c14dca07SEnric Balletbo i Serra break; 154c14dca07SEnric Balletbo i Serra } 155c14dca07SEnric Balletbo i Serra st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE; 156c14dca07SEnric Balletbo i Serra st->core.param.sensor_range.data = val; 157c14dca07SEnric Balletbo i Serra 158c14dca07SEnric Balletbo i Serra /* Always roundup, so caller gets at least what it asks for. */ 159c14dca07SEnric Balletbo i Serra st->core.param.sensor_range.roundup = 1; 160c14dca07SEnric Balletbo i Serra 161c14dca07SEnric Balletbo i Serra ret = cros_ec_motion_send_host_cmd(&st->core, 0); 162c14dca07SEnric Balletbo i Serra break; 163c14dca07SEnric Balletbo i Serra default: 164c14dca07SEnric Balletbo i Serra ret = cros_ec_sensors_core_write( 165c14dca07SEnric Balletbo i Serra &st->core, chan, val, val2, mask); 166c14dca07SEnric Balletbo i Serra break; 167c14dca07SEnric Balletbo i Serra } 168c14dca07SEnric Balletbo i Serra 169c14dca07SEnric Balletbo i Serra mutex_unlock(&st->core.cmd_lock); 170c14dca07SEnric Balletbo i Serra 171c14dca07SEnric Balletbo i Serra return ret; 172c14dca07SEnric Balletbo i Serra } 173c14dca07SEnric Balletbo i Serra 174c14dca07SEnric Balletbo i Serra static const struct iio_info ec_sensors_info = { 175c14dca07SEnric Balletbo i Serra .read_raw = &cros_ec_sensors_read, 176c14dca07SEnric Balletbo i Serra .write_raw = &cros_ec_sensors_write, 177c14dca07SEnric Balletbo i Serra }; 178c14dca07SEnric Balletbo i Serra 179c14dca07SEnric Balletbo i Serra static int cros_ec_sensors_probe(struct platform_device *pdev) 180c14dca07SEnric Balletbo i Serra { 181c14dca07SEnric Balletbo i Serra struct device *dev = &pdev->dev; 182c14dca07SEnric Balletbo i Serra struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent); 183c14dca07SEnric Balletbo i Serra struct iio_dev *indio_dev; 184c14dca07SEnric Balletbo i Serra struct cros_ec_sensors_state *state; 185c14dca07SEnric Balletbo i Serra struct iio_chan_spec *channel; 186c14dca07SEnric Balletbo i Serra int ret, i; 187c14dca07SEnric Balletbo i Serra 188c14dca07SEnric Balletbo i Serra if (!ec_dev || !ec_dev->ec_dev) { 189c14dca07SEnric Balletbo i Serra dev_warn(&pdev->dev, "No CROS EC device found.\n"); 190c14dca07SEnric Balletbo i Serra return -EINVAL; 191c14dca07SEnric Balletbo i Serra } 192c14dca07SEnric Balletbo i Serra 193c14dca07SEnric Balletbo i Serra indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*state)); 194c14dca07SEnric Balletbo i Serra if (!indio_dev) 195c14dca07SEnric Balletbo i Serra return -ENOMEM; 196c14dca07SEnric Balletbo i Serra 197c14dca07SEnric Balletbo i Serra ret = cros_ec_sensors_core_init(pdev, indio_dev, true); 198c14dca07SEnric Balletbo i Serra if (ret) 199c14dca07SEnric Balletbo i Serra return ret; 200c14dca07SEnric Balletbo i Serra 201c14dca07SEnric Balletbo i Serra indio_dev->info = &ec_sensors_info; 202c14dca07SEnric Balletbo i Serra state = iio_priv(indio_dev); 203c14dca07SEnric Balletbo i Serra for (channel = state->channels, i = CROS_EC_SENSOR_X; 204c14dca07SEnric Balletbo i Serra i < CROS_EC_SENSOR_MAX_AXIS; i++, channel++) { 205c14dca07SEnric Balletbo i Serra /* Common part */ 206c14dca07SEnric Balletbo i Serra channel->info_mask_separate = 207c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_RAW) | 208c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_CALIBBIAS); 209c14dca07SEnric Balletbo i Serra channel->info_mask_shared_by_all = 210c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_SCALE) | 211c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_FREQUENCY) | 212c14dca07SEnric Balletbo i Serra BIT(IIO_CHAN_INFO_SAMP_FREQ); 213c14dca07SEnric Balletbo i Serra channel->scan_type.realbits = CROS_EC_SENSOR_BITS; 214c14dca07SEnric Balletbo i Serra channel->scan_type.storagebits = CROS_EC_SENSOR_BITS; 215c14dca07SEnric Balletbo i Serra channel->scan_index = i; 216c14dca07SEnric Balletbo i Serra channel->ext_info = cros_ec_sensors_ext_info; 217c14dca07SEnric Balletbo i Serra channel->modified = 1; 218c14dca07SEnric Balletbo i Serra channel->channel2 = IIO_MOD_X + i; 219c14dca07SEnric Balletbo i Serra channel->scan_type.sign = 's'; 220c14dca07SEnric Balletbo i Serra 221c14dca07SEnric Balletbo i Serra /* Sensor specific */ 222c14dca07SEnric Balletbo i Serra switch (state->core.type) { 223c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_ACCEL: 224c14dca07SEnric Balletbo i Serra channel->type = IIO_ACCEL; 225c14dca07SEnric Balletbo i Serra break; 226c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_GYRO: 227c14dca07SEnric Balletbo i Serra channel->type = IIO_ANGL_VEL; 228c14dca07SEnric Balletbo i Serra break; 229c14dca07SEnric Balletbo i Serra case MOTIONSENSE_TYPE_MAG: 230c14dca07SEnric Balletbo i Serra channel->type = IIO_MAGN; 231c14dca07SEnric Balletbo i Serra break; 232c14dca07SEnric Balletbo i Serra default: 233c14dca07SEnric Balletbo i Serra dev_err(&pdev->dev, "Unknown motion sensor\n"); 234c14dca07SEnric Balletbo i Serra return -EINVAL; 235c14dca07SEnric Balletbo i Serra } 236c14dca07SEnric Balletbo i Serra } 237c14dca07SEnric Balletbo i Serra 238c14dca07SEnric Balletbo i Serra /* Timestamp */ 239c14dca07SEnric Balletbo i Serra channel->type = IIO_TIMESTAMP; 240c14dca07SEnric Balletbo i Serra channel->channel = -1; 241c14dca07SEnric Balletbo i Serra channel->scan_index = CROS_EC_SENSOR_MAX_AXIS; 242c14dca07SEnric Balletbo i Serra channel->scan_type.sign = 's'; 243c14dca07SEnric Balletbo i Serra channel->scan_type.realbits = 64; 244c14dca07SEnric Balletbo i Serra channel->scan_type.storagebits = 64; 245c14dca07SEnric Balletbo i Serra 246c14dca07SEnric Balletbo i Serra indio_dev->channels = state->channels; 247c14dca07SEnric Balletbo i Serra indio_dev->num_channels = CROS_EC_SENSORS_MAX_CHANNELS; 248c14dca07SEnric Balletbo i Serra 249c14dca07SEnric Balletbo i Serra /* There is only enough room for accel and gyro in the io space */ 250c14dca07SEnric Balletbo i Serra if ((state->core.ec->cmd_readmem != NULL) && 251c14dca07SEnric Balletbo i Serra (state->core.type != MOTIONSENSE_TYPE_MAG)) 252c14dca07SEnric Balletbo i Serra state->core.read_ec_sensors_data = cros_ec_sensors_read_lpc; 253c14dca07SEnric Balletbo i Serra else 254c14dca07SEnric Balletbo i Serra state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd; 255c14dca07SEnric Balletbo i Serra 256754434c4SEnric Balletbo i Serra ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, 257c14dca07SEnric Balletbo i Serra cros_ec_sensors_capture, NULL); 258c14dca07SEnric Balletbo i Serra if (ret) 259c14dca07SEnric Balletbo i Serra return ret; 260c14dca07SEnric Balletbo i Serra 261754434c4SEnric Balletbo i Serra return devm_iio_device_register(dev, indio_dev); 262c14dca07SEnric Balletbo i Serra } 263c14dca07SEnric Balletbo i Serra 264c14dca07SEnric Balletbo i Serra static const struct platform_device_id cros_ec_sensors_ids[] = { 265c14dca07SEnric Balletbo i Serra { 266c14dca07SEnric Balletbo i Serra .name = "cros-ec-accel", 267c14dca07SEnric Balletbo i Serra }, 268c14dca07SEnric Balletbo i Serra { 269c14dca07SEnric Balletbo i Serra .name = "cros-ec-gyro", 270c14dca07SEnric Balletbo i Serra }, 271c14dca07SEnric Balletbo i Serra { 272c14dca07SEnric Balletbo i Serra .name = "cros-ec-mag", 273c14dca07SEnric Balletbo i Serra }, 274c14dca07SEnric Balletbo i Serra { /* sentinel */ } 275c14dca07SEnric Balletbo i Serra }; 276c14dca07SEnric Balletbo i Serra MODULE_DEVICE_TABLE(platform, cros_ec_sensors_ids); 277c14dca07SEnric Balletbo i Serra 278c14dca07SEnric Balletbo i Serra static struct platform_driver cros_ec_sensors_platform_driver = { 279c14dca07SEnric Balletbo i Serra .driver = { 280c14dca07SEnric Balletbo i Serra .name = "cros-ec-sensors", 2810dad1eceSGwendal Grignou .pm = &cros_ec_sensors_pm_ops, 282c14dca07SEnric Balletbo i Serra }, 283c14dca07SEnric Balletbo i Serra .probe = cros_ec_sensors_probe, 284c14dca07SEnric Balletbo i Serra .id_table = cros_ec_sensors_ids, 285c14dca07SEnric Balletbo i Serra }; 286c14dca07SEnric Balletbo i Serra module_platform_driver(cros_ec_sensors_platform_driver); 287c14dca07SEnric Balletbo i Serra 288c14dca07SEnric Balletbo i Serra MODULE_DESCRIPTION("ChromeOS EC 3-axis sensors driver"); 289c14dca07SEnric Balletbo i Serra MODULE_LICENSE("GPL v2"); 290