drivers/iio/light/cros_ec_light_prox.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * cros_ec_light_prox - Driver for light and prox sensors behing CrosEC.
   4  *
   5  * Copyright (C) 2017 Google, Inc
   6  */
   7
   8 #include <linux/device.h>
   9 #include <linux/iio/buffer.h>
  10 #include <linux/iio/common/cros_ec_sensors_core.h>
  11 #include <linux/iio/iio.h>
  12 #include <linux/iio/kfifo_buf.h>
  13 #include <linux/iio/trigger.h>
  14 #include <linux/iio/triggered_buffer.h>
  15 #include <linux/iio/trigger_consumer.h>
  16 #include <linux/kernel.h>
  17 #include <linux/mod_devicetable.h>
  18 #include <linux/module.h>
  19 #include <linux/platform_data/cros_ec_commands.h>
  20 #include <linux/platform_data/cros_ec_proto.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/slab.h>
  23
  24 /*
  25  * We only represent one entry for light or proximity. EC is merging different
  26  * light sensors to return the what the eye would see. For proximity, we
  27  * currently support only one light source.
  28  */
  29 #define CROS_EC_LIGHT_PROX_MAX_CHANNELS (1 + 1)
  30
  31 /* State data for ec_sensors iio driver. */
  32 struct cros_ec_light_prox_state {
  33         /* Shared by all sensors */
  34         struct cros_ec_sensors_core_state core;
  35
  36         struct iio_chan_spec channels[CROS_EC_LIGHT_PROX_MAX_CHANNELS];
  37 };
  38
  39 static int cros_ec_light_prox_read(struct iio_dev *indio_dev,
  40                                    struct iio_chan_spec const *chan,
  41                                    int *val, int *val2, long mask)
  42 {
  43         struct cros_ec_light_prox_state *st = iio_priv(indio_dev);
  44         u16 data = 0;
  45         s64 val64;
  46         int ret;
  47         int idx = chan->scan_index;
  48
  49         mutex_lock(&st->core.cmd_lock);
  50
  51         switch (mask) {
  52         case IIO_CHAN_INFO_RAW:
  53                 if (chan->type == IIO_PROXIMITY) {
  54                         ret = cros_ec_sensors_read_cmd(indio_dev, 1 << idx,
  55                                                      (s16 *)&data);
  56                         if (ret)
  57                                 break;
  58                         *val = data;
  59                         ret = IIO_VAL_INT;
  60                 } else {
  61                         ret = -EINVAL;
  62                 }
  63                 break;
  64         case IIO_CHAN_INFO_PROCESSED:
  65                 if (chan->type == IIO_LIGHT) {
  66                         ret = cros_ec_sensors_read_cmd(indio_dev, 1 << idx,
  67                                                      (s16 *)&data);
  68                         if (ret)
  69                                 break;
  70                         /*
  71                          * The data coming from the light sensor is
  72                          * pre-processed and represents the ambient light
  73                          * illuminance reading expressed in lux.
  74                          */
  75                         *val = data;
  76                         ret = IIO_VAL_INT;
  77                 } else {
  78                         ret = -EINVAL;
  79                 }
  80                 break;
  81         case IIO_CHAN_INFO_CALIBBIAS:
  82                 st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET;
  83                 st->core.param.sensor_offset.flags = 0;
  84
  85                 ret = cros_ec_motion_send_host_cmd(&st->core, 0);
  86                 if (ret)
  87                         break;
  88
  89                 /* Save values */
  90                 st->core.calib[0].offset =
  91                         st->core.resp->sensor_offset.offset[0];
  92
  93                 *val = st->core.calib[idx].offset;
  94                 ret = IIO_VAL_INT;
  95                 break;
  96         case IIO_CHAN_INFO_CALIBSCALE:
  97                 /*
  98                  * RANGE is used for calibration
  99                  * scale is a number x.y, where x is coded on 16 bits,
 100                  * y coded on 16 bits, between 0 and 9999.
 101                  */
 102                 st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
 103                 st->core.param.sensor_range.data = EC_MOTION_SENSE_NO_VALUE;
 104
 105                 ret = cros_ec_motion_send_host_cmd(&st->core, 0);
 106                 if (ret)
 107                         break;
 108
 109                 val64 = st->core.resp->sensor_range.ret;
 110                 *val = val64 >> 16;
 111                 *val2 = (val64 & 0xffff) * 100;
 112                 ret = IIO_VAL_INT_PLUS_MICRO;
 113                 break;
 114         default:
 115                 ret = cros_ec_sensors_core_read(&st->core, chan, val, val2,
 116                                                 mask);
 117                 break;
 118         }
 119
 120         mutex_unlock(&st->core.cmd_lock);
 121
 122         return ret;
 123 }
 124
 125 static int cros_ec_light_prox_write(struct iio_dev *indio_dev,
 126                                struct iio_chan_spec const *chan,
 127                                int val, int val2, long mask)
 128 {
 129         struct cros_ec_light_prox_state *st = iio_priv(indio_dev);
 130         int ret;
 131         int idx = chan->scan_index;
 132
 133         mutex_lock(&st->core.cmd_lock);
 134
 135         switch (mask) {
 136         case IIO_CHAN_INFO_CALIBBIAS:
 137                 st->core.calib[idx].offset = val;
 138                 /* Send to EC for each axis, even if not complete */
 139                 st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET;
 140                 st->core.param.sensor_offset.flags = MOTION_SENSE_SET_OFFSET;
 141                 st->core.param.sensor_offset.offset[0] =
 142                         st->core.calib[0].offset;
 143                 st->core.param.sensor_offset.temp =
 144                                         EC_MOTION_SENSE_INVALID_CALIB_TEMP;
 145                 ret = cros_ec_motion_send_host_cmd(&st->core, 0);
 146                 break;
 147         case IIO_CHAN_INFO_CALIBSCALE:
 148                 st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
 149                 st->core.curr_range = (val << 16) | (val2 / 100);
 150                 st->core.param.sensor_range.data = st->core.curr_range;
 151                 ret = cros_ec_motion_send_host_cmd(&st->core, 0);
 152                 if (ret == 0)
 153                         st->core.range_updated = true;
 154                 break;
 155         default:
 156                 ret = cros_ec_sensors_core_write(&st->core, chan, val, val2,
 157                                                  mask);
 158                 break;
 159         }
 160
 161         mutex_unlock(&st->core.cmd_lock);
 162
 163         return ret;
 164 }
 165
 166 static const struct iio_info cros_ec_light_prox_info = {
 167         .read_raw = &cros_ec_light_prox_read,
 168         .write_raw = &cros_ec_light_prox_write,
 169         .read_avail = &cros_ec_sensors_core_read_avail,
 170 };
 171
 172 static int cros_ec_light_prox_probe(struct platform_device *pdev)
 173 {
 174         struct device *dev = &pdev->dev;
 175         struct iio_dev *indio_dev;
 176         struct cros_ec_light_prox_state *state;
 177         struct iio_chan_spec *channel;
 178         int ret;
 179
 180         indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
 181         if (!indio_dev)
 182                 return -ENOMEM;
 183
 184         ret = cros_ec_sensors_core_init(pdev, indio_dev, true,
 185                                         cros_ec_sensors_capture);
 186         if (ret)
 187                 return ret;
 188
 189         indio_dev->info = &cros_ec_light_prox_info;
 190         state = iio_priv(indio_dev);
 191         channel = state->channels;
 192
 193         /* Common part */
 194         channel->info_mask_shared_by_all =
 195                 BIT(IIO_CHAN_INFO_SAMP_FREQ);
 196         channel->info_mask_shared_by_all_available =
 197                 BIT(IIO_CHAN_INFO_SAMP_FREQ);
 198         channel->scan_type.realbits = CROS_EC_SENSOR_BITS;
 199         channel->scan_type.storagebits = CROS_EC_SENSOR_BITS;
 200         channel->scan_type.shift = 0;
 201         channel->scan_index = 0;
 202         channel->ext_info = cros_ec_sensors_ext_info;
 203         channel->scan_type.sign = 'u';
 204
 205         /* Sensor specific */
 206         switch (state->core.type) {
 207         case MOTIONSENSE_TYPE_LIGHT:
 208                 channel->type = IIO_LIGHT;
 209                 channel->info_mask_separate =
 210                         BIT(IIO_CHAN_INFO_PROCESSED) |
 211                         BIT(IIO_CHAN_INFO_CALIBBIAS) |
 212                         BIT(IIO_CHAN_INFO_CALIBSCALE);
 213                 break;
 214         case MOTIONSENSE_TYPE_PROX:
 215                 channel->type = IIO_PROXIMITY;
 216                 channel->info_mask_separate =
 217                         BIT(IIO_CHAN_INFO_RAW) |
 218                         BIT(IIO_CHAN_INFO_CALIBBIAS) |
 219                         BIT(IIO_CHAN_INFO_CALIBSCALE);
 220                 break;
 221         default:
 222                 dev_warn(dev, "Unknown motion sensor\n");
 223                 return -EINVAL;
 224         }
 225
 226         /* Timestamp */
 227         channel++;
 228         channel->type = IIO_TIMESTAMP;
 229         channel->channel = -1;
 230         channel->scan_index = 1;
 231         channel->scan_type.sign = 's';
 232         channel->scan_type.realbits = 64;
 233         channel->scan_type.storagebits = 64;
 234
 235         indio_dev->channels = state->channels;
 236
 237         indio_dev->num_channels = CROS_EC_LIGHT_PROX_MAX_CHANNELS;
 238
 239         state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd;
 240
 241         return cros_ec_sensors_core_register(dev, indio_dev,
 242                                              cros_ec_sensors_push_data);
 243 }
 244
 245 static const struct platform_device_id cros_ec_light_prox_ids[] = {
 246         {
 247                 .name = "cros-ec-prox",
 248         },
 249         {
 250                 .name = "cros-ec-light",
 251         },
 252         { /* sentinel */ }
 253 };
 254 MODULE_DEVICE_TABLE(platform, cros_ec_light_prox_ids);
 255
 256 static struct platform_driver cros_ec_light_prox_platform_driver = {
 257         .driver = {
 258                 .name   = "cros-ec-light-prox",
 259                 .pm     = &cros_ec_sensors_pm_ops,
 260         },
 261         .probe          = cros_ec_light_prox_probe,
 262         .id_table       = cros_ec_light_prox_ids,
 263 };
 264 module_platform_driver(cros_ec_light_prox_platform_driver);
 265
 266 MODULE_DESCRIPTION("ChromeOS EC light/proximity sensors driver");
 267 MODULE_LICENSE("GPL v2");