int cros_ec_sysfs_set_input_attr_by_int(const char *path,
const char *attr, int value)
{
char buf[INT32_CHAR_LEN];
size_t n = snprintf(buf, sizeof(buf), "%d", value);
if (n > sizeof(buf)) {
return -1;
}
return cros_ec_sysfs_set_input_attr(path, attr, buf, n);
}
/*
* cros_ec_calibrate_3d_sensor: calibrate Accel or Gyro.
*
* In factory, calibration data is in VPD.
* It is available from user space by reading /sys/firmware/vpd/ro/<Key>.
* Key names are similar to iio: <type>_<axis>_calibbias,
* when type is in_accel or in_anglvel and axis is x,y, or z.
*/
static int cros_ec_calibrate_3d_sensor(int sensor_type, const char *device_name)
{
const char vpd_path[] = "/sys/firmware/vpd/ro";
char calib_value[MAX_AXIS][20];
char calib_key[MAX_AXIS][IIO_MAX_NAME_LENGTH];
bool calib_data_valid = true;
for (int i = X ; i < MAX_AXIS; i++) {
snprintf(calib_key[i], sizeof(calib_key[i]), "%s_%c_calibbias",
cros_ec_iio_axis_names[sensor_type], 'x' + i);
}
for (int i = X ; i < MAX_AXIS; i++) {
if (cros_ec_sysfs_get_attr(vpd_path, calib_key[i], calib_value[i])) {
ALOGI("Calibration key %s missing.\n", calib_key[i]);
calib_data_valid = false;
break;
}
}
if (calib_data_valid && sensor_type == CROS_EC_ACCEL) {
for (int i = X ; i < MAX_AXIS; i++) {
/*
* Workaround for invalid calibration values obveserved on several
* devices (b/26927000). If the value seems bogus, ignore the whole
* calibration.
* If one calibration axis is greater than 2 m/s^2, ignore.
*/
int value = atoi(calib_value[i]);
if (abs(value) > (2 * 1024 * 100 / 981)) {
ALOGE("Calibration data invalid on axis %d: %d\n", i, value);
calib_data_valid = false;
break;
}
}
}
for (int i = X ; i < MAX_AXIS; i++) {
const char *value = (calib_data_valid ? calib_value[i] : "0");
if (cros_ec_sysfs_set_input_attr(device_name, calib_key[i],
value, strlen(value))) {
ALOGE("Writing bias %s to %s for device %s failed.\n",
calib_key[i], value, device_name);
}
}
return 0;
}
/*
* Constructor.
*
* Setup and open the ring buffer.
*/
CrosECSensor::CrosECSensor(
struct cros_ec_sensor_info *sensor_info,
size_t sensor_nb,
struct cros_ec_gesture_info *gesture_info,
size_t gesture_nb,
const char *ring_device_name,
const char *trigger_name)
: mSensorInfo(sensor_info),
mSensorNb(sensor_nb),
mGestureInfo(gesture_info),
mGestureNb(gesture_nb)
{
char ring_buffer_name[IIO_MAX_NAME_LENGTH] = "/dev/";
strcat(ring_buffer_name, ring_device_name);
mDataFd = open(ring_buffer_name, O_RDONLY);
if (mDataFd < 0) {
ALOGE("open file '%s' failed: %s\n",
ring_buffer_name, strerror(errno));
}
strcpy(mRingPath, ring_device_name);
/* Be sure the buffer is disbabled before altering parameters */
if (cros_ec_sysfs_set_input_attr_by_int(mRingPath, "buffer/enable", 0) < 0) {
ALOGE("disable IIO buffer failed: %s\n", strerror(errno));
return;
}
if (cros_ec_sysfs_set_input_attr(mRingPath, "trigger/current_trigger",
trigger_name, strlen(trigger_name))) {
ALOGE("Unable to set trigger name: %s\n", strerror(errno));
return;
}
if (cros_ec_sysfs_set_input_attr_by_int(mRingPath, "buffer/length",
IIO_MAX_BUFF_SIZE) < 0) {
ALOGE("set IIO buffer length (%d) failed: %s\n",
IIO_MAX_BUFF_SIZE, strerror(errno));
}
if (cros_ec_sysfs_set_input_attr_by_int(mRingPath, "buffer/enable", 1) < 0) {
ALOGE("enable IIO buffer failed: %s\n",
strerror(errno));
return;
}
}
