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