summaryrefslogtreecommitdiffstats
path: root/drivers/platform/chrome/cros_ec_sensorhub.c
blob: 31fb8bdaad5a35b6fba851f660927ae44152ec01 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
// SPDX-License-Identifier: GPL-2.0
/*
 * Sensor HUB driver that discovers sensors behind a ChromeOS Embedded
 * Controller.
 *
 * Copyright 2019 Google LLC
 */

#include <linux/init.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/platform_data/cros_ec_sensorhub.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/types.h>

#define DRV_NAME		"cros-ec-sensorhub"

static void cros_ec_sensorhub_free_sensor(void *arg)
{
	struct platform_device *pdev = arg;

	platform_device_unregister(pdev);
}

static int cros_ec_sensorhub_allocate_sensor(struct device *parent,
					     char *sensor_name,
					     int sensor_num)
{
	struct cros_ec_sensor_platform sensor_platforms = {
		.sensor_num = sensor_num,
	};
	struct platform_device *pdev;

	pdev = platform_device_register_data(parent, sensor_name,
					     PLATFORM_DEVID_AUTO,
					     &sensor_platforms,
					     sizeof(sensor_platforms));
	if (IS_ERR(pdev))
		return PTR_ERR(pdev);

	return devm_add_action_or_reset(parent,
					cros_ec_sensorhub_free_sensor,
					pdev);
}

static int cros_ec_sensorhub_register(struct device *dev,
				      struct cros_ec_sensorhub *sensorhub)
{
	int sensor_type[MOTIONSENSE_TYPE_MAX] = { 0 };
	struct cros_ec_command *msg = sensorhub->msg;
	struct cros_ec_dev *ec = sensorhub->ec;
	int ret, i;
	char *name;


	msg->version = 1;
	msg->insize = sizeof(struct ec_response_motion_sense);
	msg->outsize = sizeof(struct ec_params_motion_sense);

	for (i = 0; i < sensorhub->sensor_num; i++) {
		sensorhub->params->cmd = MOTIONSENSE_CMD_INFO;
		sensorhub->params->info.sensor_num = i;

		ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
		if (ret < 0) {
			dev_warn(dev, "no info for EC sensor %d : %d/%d\n",
				 i, ret, msg->result);
			continue;
		}

		switch (sensorhub->resp->info.type) {
		case MOTIONSENSE_TYPE_ACCEL:
			name = "cros-ec-accel";
			break;
		case MOTIONSENSE_TYPE_BARO:
			name = "cros-ec-baro";
			break;
		case MOTIONSENSE_TYPE_GYRO:
			name = "cros-ec-gyro";
			break;
		case MOTIONSENSE_TYPE_MAG:
			name = "cros-ec-mag";
			break;
		case MOTIONSENSE_TYPE_PROX:
			name = "cros-ec-prox";
			break;
		case MOTIONSENSE_TYPE_LIGHT:
			name = "cros-ec-light";
			break;
		case MOTIONSENSE_TYPE_ACTIVITY:
			name = "cros-ec-activity";
			break;
		default:
			dev_warn(dev, "unknown type %d\n",
				 sensorhub->resp->info.type);
			continue;
		}

		ret = cros_ec_sensorhub_allocate_sensor(dev, name, i);
		if (ret)
			return ret;

		sensor_type[sensorhub->resp->info.type]++;
	}

	if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2)
		ec->has_kb_wake_angle = true;

	if (cros_ec_check_features(ec,
				   EC_FEATURE_REFINED_TABLET_MODE_HYSTERESIS)) {
		ret = cros_ec_sensorhub_allocate_sensor(dev,
							"cros-ec-lid-angle",
							0);
		if (ret)
			return ret;
	}

	return 0;
}

static int cros_ec_sensorhub_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct cros_ec_dev *ec = dev_get_drvdata(dev->parent);
	struct cros_ec_sensorhub *data;
	struct cros_ec_command *msg;
	int ret, i, sensor_num;

	msg = devm_kzalloc(dev, sizeof(struct cros_ec_command) +
			   max((u16)sizeof(struct ec_params_motion_sense),
			       ec->ec_dev->max_response), GFP_KERNEL);
	if (!msg)
		return -ENOMEM;

	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;

	data = devm_kzalloc(dev, sizeof(struct cros_ec_sensorhub), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	mutex_init(&data->cmd_lock);

	data->dev = dev;
	data->ec = ec;
	data->msg = msg;
	data->params = (struct ec_params_motion_sense *)msg->data;
	data->resp = (struct ec_response_motion_sense *)msg->data;

	dev_set_drvdata(dev, data);

	/* Check whether this EC is a sensor hub. */
	if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE)) {
		sensor_num = cros_ec_get_sensor_count(ec);
		if (sensor_num < 0) {
			dev_err(dev,
				"Unable to retrieve sensor information (err:%d)\n",
				sensor_num);
			return sensor_num;
		}
		if (sensor_num == 0) {
			dev_err(dev, "Zero sensors reported.\n");
			return -EINVAL;
		}
		data->sensor_num = sensor_num;

		/*
		 * Prepare the ring handler before enumering the
		 * sensors.
		 */
		if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
			ret = cros_ec_sensorhub_ring_allocate(data);
			if (ret)
				return ret;
		}

		/* Enumerate the sensors.*/
		ret = cros_ec_sensorhub_register(dev, data);
		if (ret)
			return ret;

		/*
		 * When the EC does not have a FIFO, the sensors will query
		 * their data themselves via sysfs or a software trigger.
		 */
		if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
			ret = cros_ec_sensorhub_ring_add(data);
			if (ret)
				return ret;
			/*
			 * The msg and its data is not under the control of the
			 * ring handler.
			 */
			return devm_add_action_or_reset(dev,
					cros_ec_sensorhub_ring_remove,
					data);
		}

	} else {
		/*
		 * If the device has sensors but does not claim to
		 * be a sensor hub, we are in legacy mode.
		 */
		data->sensor_num = 2;
		for (i = 0; i < data->sensor_num; i++) {
			ret = cros_ec_sensorhub_allocate_sensor(dev,
						"cros-ec-accel-legacy", i);
			if (ret)
				return ret;
		}
	}


	return 0;
}

#ifdef CONFIG_PM_SLEEP
/*
 * When the EC is suspending, we must stop sending interrupt,
 * we may use the same interrupt line for waking up the device.
 * Tell the EC to stop sending non-interrupt event on the iio ring.
 */
static int cros_ec_sensorhub_suspend(struct device *dev)
{
	struct cros_ec_sensorhub *sensorhub = dev_get_drvdata(dev);
	struct cros_ec_dev *ec = sensorhub->ec;

	if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))
		return cros_ec_sensorhub_ring_fifo_enable(sensorhub, false);
	return 0;
}

static int cros_ec_sensorhub_resume(struct device *dev)
{
	struct cros_ec_sensorhub *sensorhub = dev_get_drvdata(dev);
	struct cros_ec_dev *ec = sensorhub->ec;

	if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))
		return cros_ec_sensorhub_ring_fifo_enable(sensorhub, true);
	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(cros_ec_sensorhub_pm_ops,
		cros_ec_sensorhub_suspend,
		cros_ec_sensorhub_resume);

static struct platform_driver cros_ec_sensorhub_driver = {
	.driver = {
		.name = DRV_NAME,
		.pm = &cros_ec_sensorhub_pm_ops,
	},
	.probe = cros_ec_sensorhub_probe,
};

module_platform_driver(cros_ec_sensorhub_driver);

MODULE_ALIAS("platform:" DRV_NAME);
MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");
MODULE_DESCRIPTION("ChromeOS EC MEMS Sensor Hub Driver");
MODULE_LICENSE("GPL");