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
|
// SPDX-License-Identifier: GPL-2.0
/*
* Driver for older Chrome OS EC accelerometer
*
* Copyright 2017 Google, Inc
*
* This driver uses the memory mapper cros-ec interface to communicate
* with the Chrome OS EC about accelerometer data or older commands.
* Accelerometer access is presented through iio sysfs.
*/
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/iio/buffer.h>
#include <linux/iio/common/cros_ec_sensors_core.h>
#include <linux/iio/iio.h>
#include <linux/iio/kfifo_buf.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/platform_device.h>
#define DRV_NAME "cros-ec-accel-legacy"
#define CROS_EC_SENSOR_LEGACY_NUM 2
/*
* Sensor scale hard coded at 10 bits per g, computed as:
* g / (2^10 - 1) = 0.009586168; with g = 9.80665 m.s^-2
*/
#define ACCEL_LEGACY_NSCALE 9586168
/*
* Sensor frequency is hard-coded to 10Hz.
*/
static const int cros_ec_legacy_sample_freq[] = { 10, 0 };
static int cros_ec_accel_legacy_read_cmd(struct iio_dev *indio_dev,
unsigned long scan_mask, s16 *data)
{
struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
int ret;
unsigned int i;
u8 sensor_num;
/*
* Read all sensor data through a command.
* Save sensor_num, it is assumed to stay.
*/
sensor_num = st->param.info.sensor_num;
st->param.cmd = MOTIONSENSE_CMD_DUMP;
st->param.dump.max_sensor_count = CROS_EC_SENSOR_LEGACY_NUM;
ret = cros_ec_motion_send_host_cmd(st,
sizeof(st->resp->dump) + CROS_EC_SENSOR_LEGACY_NUM *
sizeof(struct ec_response_motion_sensor_data));
st->param.info.sensor_num = sensor_num;
if (ret != 0) {
dev_warn(&indio_dev->dev, "Unable to read sensor data\n");
return ret;
}
for_each_set_bit(i, &scan_mask, indio_dev->masklength) {
*data = st->resp->dump.sensor[sensor_num].data[i] *
st->sign[i];
data++;
}
return 0;
}
static int cros_ec_accel_legacy_read(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
s16 data = 0;
int ret;
int idx = chan->scan_index;
mutex_lock(&st->cmd_lock);
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = st->read_ec_sensors_data(indio_dev, 1 << idx, &data);
if (ret < 0)
break;
ret = IIO_VAL_INT;
*val = data;
break;
case IIO_CHAN_INFO_SCALE:
WARN_ON(st->type != MOTIONSENSE_TYPE_ACCEL);
*val = 0;
*val2 = ACCEL_LEGACY_NSCALE;
ret = IIO_VAL_INT_PLUS_NANO;
break;
case IIO_CHAN_INFO_CALIBBIAS:
/* Calibration not supported. */
*val = 0;
ret = IIO_VAL_INT;
break;
case IIO_CHAN_INFO_SAMP_FREQ:
*val = cros_ec_legacy_sample_freq[0];
*val2 = cros_ec_legacy_sample_freq[1];
ret = IIO_VAL_INT_PLUS_MICRO;
break;
default:
ret = cros_ec_sensors_core_read(st, chan, val, val2,
mask);
break;
}
mutex_unlock(&st->cmd_lock);
return ret;
}
static int cros_ec_accel_legacy_write(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
/*
* Do nothing but don't return an error code to allow calibration
* script to work.
*/
if (mask == IIO_CHAN_INFO_CALIBBIAS)
return 0;
return -EINVAL;
}
/**
* cros_ec_accel_legacy_read_avail() - get available values
* @indio_dev: pointer to state information for device
* @chan: channel specification structure table
* @vals: list of available values
* @type: type of data returned
* @length: number of data returned in the array
* @mask: specifies which values to be requested
*
* Return: an error code or IIO_AVAIL_LIST
*/
static int cros_ec_accel_legacy_read_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals,
int *type,
int *length,
long mask)
{
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
*length = ARRAY_SIZE(cros_ec_legacy_sample_freq);
*vals = cros_ec_legacy_sample_freq;
*type = IIO_VAL_INT_PLUS_MICRO;
return IIO_AVAIL_LIST;
}
return -EINVAL;
}
static const struct iio_info cros_ec_accel_legacy_info = {
.read_raw = &cros_ec_accel_legacy_read,
.write_raw = &cros_ec_accel_legacy_write,
.read_avail = &cros_ec_accel_legacy_read_avail,
};
/*
* Present the channel using HTML5 standard:
* need to invert X and Y and invert some lid axis.
*/
#define CROS_EC_ACCEL_ROTATE_AXIS(_axis) \
((_axis) == CROS_EC_SENSOR_Z ? CROS_EC_SENSOR_Z : \
((_axis) == CROS_EC_SENSOR_X ? CROS_EC_SENSOR_Y : \
CROS_EC_SENSOR_X))
#define CROS_EC_ACCEL_LEGACY_CHAN(_axis) \
{ \
.type = IIO_ACCEL, \
.channel2 = IIO_MOD_X + (_axis), \
.modified = 1, \
.info_mask_separate = \
BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_CALIBBIAS), \
.info_mask_shared_by_all = \
BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.info_mask_shared_by_all_available = \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.ext_info = cros_ec_sensors_ext_info, \
.scan_type = { \
.sign = 's', \
.realbits = CROS_EC_SENSOR_BITS, \
.storagebits = CROS_EC_SENSOR_BITS, \
}, \
.scan_index = CROS_EC_ACCEL_ROTATE_AXIS(_axis), \
} \
static const struct iio_chan_spec cros_ec_accel_legacy_channels[] = {
CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_X),
CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_Y),
CROS_EC_ACCEL_LEGACY_CHAN(CROS_EC_SENSOR_Z),
IIO_CHAN_SOFT_TIMESTAMP(CROS_EC_SENSOR_MAX_AXIS)
};
static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct iio_dev *indio_dev;
struct cros_ec_sensors_core_state *state;
int ret;
indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*state));
if (!indio_dev)
return -ENOMEM;
ret = cros_ec_sensors_core_init(pdev, indio_dev, true,
cros_ec_sensors_capture, NULL);
if (ret)
return ret;
indio_dev->info = &cros_ec_accel_legacy_info;
state = iio_priv(indio_dev);
if (state->ec->cmd_readmem != NULL)
state->read_ec_sensors_data = cros_ec_sensors_read_lpc;
else
state->read_ec_sensors_data = cros_ec_accel_legacy_read_cmd;
indio_dev->channels = cros_ec_accel_legacy_channels;
indio_dev->num_channels = ARRAY_SIZE(cros_ec_accel_legacy_channels);
/* The lid sensor needs to be presented inverted. */
if (state->loc == MOTIONSENSE_LOC_LID) {
state->sign[CROS_EC_SENSOR_X] = -1;
state->sign[CROS_EC_SENSOR_Z] = -1;
}
return devm_iio_device_register(dev, indio_dev);
}
static struct platform_driver cros_ec_accel_platform_driver = {
.driver = {
.name = DRV_NAME,
},
.probe = cros_ec_accel_legacy_probe,
};
module_platform_driver(cros_ec_accel_platform_driver);
MODULE_DESCRIPTION("ChromeOS EC legacy accelerometer driver");
MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" DRV_NAME);
|
