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. */
32struct 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
39static 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
125static 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
166static 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
172static 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
245static 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};
254MODULE_DEVICE_TABLE(platform, cros_ec_light_prox_ids);
255
256static 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};
264module_platform_driver(cros_ec_light_prox_platform_driver);
265
266MODULE_DESCRIPTION("ChromeOS EC light/proximity sensors driver");
267MODULE_LICENSE("GPL v2");
268