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
cros_ec_light_prox_read(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)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
cros_ec_light_prox_write(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)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.curr_range = (val << 16) | (val2 / 100);
149 st->core.param.sensor_range.data = st->core.curr_range;
150 ret = cros_ec_motion_send_host_cmd(&st->core, 0);
151 if (ret == 0)
152 st->core.range_updated = true;
153 break;
154 default:
155 ret = cros_ec_sensors_core_write(&st->core, chan, val, val2,
156 mask);
157 break;
158 }
159
160 mutex_unlock(&st->core.cmd_lock);
161
162 return ret;
163 }
164
165 static const struct iio_info cros_ec_light_prox_info = {
166 .read_raw = &cros_ec_light_prox_read,
167 .write_raw = &cros_ec_light_prox_write,
168 .read_avail = &cros_ec_sensors_core_read_avail,
169 };
170
cros_ec_light_prox_probe(struct platform_device * pdev)171 static int cros_ec_light_prox_probe(struct platform_device *pdev)
172 {
173 struct device *dev = &pdev->dev;
174 struct iio_dev *indio_dev;
175 struct cros_ec_light_prox_state *state;
176 struct iio_chan_spec *channel;
177 int ret;
178
179 indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
180 if (!indio_dev)
181 return -ENOMEM;
182
183 ret = cros_ec_sensors_core_init(pdev, indio_dev, true,
184 cros_ec_sensors_capture,
185 cros_ec_sensors_push_data,
186 true);
187 if (ret)
188 return ret;
189
190 indio_dev->info = &cros_ec_light_prox_info;
191 state = iio_priv(indio_dev);
192 state->core.type = state->core.resp->info.type;
193 state->core.loc = state->core.resp->info.location;
194 channel = state->channels;
195
196 /* Common part */
197 channel->info_mask_shared_by_all =
198 BIT(IIO_CHAN_INFO_SAMP_FREQ);
199 channel->info_mask_shared_by_all_available =
200 BIT(IIO_CHAN_INFO_SAMP_FREQ);
201 channel->scan_type.realbits = CROS_EC_SENSOR_BITS;
202 channel->scan_type.storagebits = CROS_EC_SENSOR_BITS;
203 channel->scan_type.shift = 0;
204 channel->scan_index = 0;
205 channel->ext_info = cros_ec_sensors_ext_info;
206 channel->scan_type.sign = 'u';
207
208 /* Sensor specific */
209 switch (state->core.type) {
210 case MOTIONSENSE_TYPE_LIGHT:
211 channel->type = IIO_LIGHT;
212 channel->info_mask_separate =
213 BIT(IIO_CHAN_INFO_PROCESSED) |
214 BIT(IIO_CHAN_INFO_CALIBBIAS) |
215 BIT(IIO_CHAN_INFO_CALIBSCALE);
216 break;
217 case MOTIONSENSE_TYPE_PROX:
218 channel->type = IIO_PROXIMITY;
219 channel->info_mask_separate =
220 BIT(IIO_CHAN_INFO_RAW) |
221 BIT(IIO_CHAN_INFO_CALIBBIAS) |
222 BIT(IIO_CHAN_INFO_CALIBSCALE);
223 break;
224 default:
225 dev_warn(dev, "Unknown motion sensor\n");
226 return -EINVAL;
227 }
228
229 /* Timestamp */
230 channel++;
231 channel->type = IIO_TIMESTAMP;
232 channel->channel = -1;
233 channel->scan_index = 1;
234 channel->scan_type.sign = 's';
235 channel->scan_type.realbits = 64;
236 channel->scan_type.storagebits = 64;
237
238 indio_dev->channels = state->channels;
239
240 indio_dev->num_channels = CROS_EC_LIGHT_PROX_MAX_CHANNELS;
241
242 state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd;
243
244 return devm_iio_device_register(dev, indio_dev);
245 }
246
247 static const struct platform_device_id cros_ec_light_prox_ids[] = {
248 {
249 .name = "cros-ec-prox",
250 },
251 {
252 .name = "cros-ec-light",
253 },
254 { /* sentinel */ }
255 };
256 MODULE_DEVICE_TABLE(platform, cros_ec_light_prox_ids);
257
258 static struct platform_driver cros_ec_light_prox_platform_driver = {
259 .driver = {
260 .name = "cros-ec-light-prox",
261 .pm = &cros_ec_sensors_pm_ops,
262 },
263 .probe = cros_ec_light_prox_probe,
264 .id_table = cros_ec_light_prox_ids,
265 };
266 module_platform_driver(cros_ec_light_prox_platform_driver);
267
268 MODULE_DESCRIPTION("ChromeOS EC light/proximity sensors driver");
269 MODULE_LICENSE("GPL v2");
270