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
cros_ec_light_prox_read(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)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
cros_ec_light_prox_write(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)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
cros_ec_light_prox_probe(struct platform_device * pdev)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");
268