2 * Copyright (C) 2014 Intel Corporation.
8 #define MAX_DEVICES 8 /* Check iio devices 0 to MAX_DEVICES-1 */
9 #define MAX_SENSORS 10 /* We can handle as many sensors */
10 #define MAX_CHANNELS 4 /* We can handle as many channels per sensor */
11 #define MAX_TRIGGERS 8 /* Check for triggers 0 to MAX_TRIGGERS-1 */
13 #define DEV_FILE_PATH "/dev/iio:device%d"
14 #define BASE_PATH "/sys/bus/iio/devices/iio:device%d/"
15 #define TRIGGER_FILE_PATH "/sys/bus/iio/devices/trigger%d/name"
17 #define CHANNEL_PATH BASE_PATH "scan_elements/"
18 #define ENABLE_PATH BASE_PATH "buffer/enable"
19 #define NAME_PATH BASE_PATH "name"
20 #define TRIGGER_PATH BASE_PATH "trigger/current_trigger"
21 #define SENSOR_OFFSET_PATH BASE_PATH "in_%s_offset"
22 #define SENSOR_SCALE_PATH BASE_PATH "in_%s_scale"
23 #define SENSOR_SAMPLING_PATH BASE_PATH "in_%s_sampling_frequency"
24 #define DEVICE_SAMPLING_PATH BASE_PATH "sampling_frequency"
25 #define DEVICE_AVAIL_FREQ_PATH BASE_PATH "sampling_frequency_available"
26 #define ILLUMINATION_CALIBPATH BASE_PATH "in_illuminance_calibscale"
28 #define PROP_BASE "ro.iio.%s.%s" /* Note: PROPERTY_KEY_MAX is small */
30 #define MAX_EVENTS 800 /* 800 hz */
31 #define MAX_TYPE_SPEC_LEN 32 /* Channel type spec len; ex: "le:u10/16>>0" */
32 #define MAX_SENSOR_REPORT_SIZE 32 /* Sensor report buffer size */
34 #define MAX_NAME_SIZE 32
36 #define ARRAY_SIZE(x) sizeof(x)/sizeof(x[0])
39 typedef uint64_t flag_t;
40 typedef int64_t max_delay_t;
42 typedef uint32_t flag_t;
43 typedef int32_t max_delay_t;
46 struct channel_descriptor_t
48 const char *name; /* channel name ; ex: x */
50 /* sysfs entries located under scan_elements */
51 const char *en_path; /* Enabled sysfs file name ; ex: "in_temp_en" */
52 const char *type_path; /* _type sysfs file name */
53 const char *index_path; /* _index sysfs file name */
55 /* sysfs entries located in /sys/bus/iio/devices/iio:deviceX */
56 const char *raw_path; /* _raw sysfs file name */
57 const char *input_path; /* _input sysfs file name */
58 const char *scale_path; /* _scale sysfs file name */
61 struct sensor_catalog_entry_t
63 const char *tag; /* Prefix such as "accel", "gyro", "temp"... */
64 const int type; /* Sensor type ; ex: SENSOR_TYPE_ACCELEROMETER */
65 const int num_channels; /* Expected iio channels for this sensor */
66 struct channel_descriptor_t channel[MAX_CHANNELS];
80 int offset; /* Offset in bytes within the iio character device report */
81 int size; /* Field size in bytes */
82 float scale; /* scale for each channel */
83 char type_spec[MAX_TYPE_SPEC_LEN]; /* From driver; ex: le:u10/16>>0 */
84 struct datum_info_t type_info; /* Decoded contents of type spec */
85 float opt_scale; /* Optional correction scale read from a property such
86 * as iio.accel.x.scale, allowing late compensation of
87 * problems such as misconfigured axes ; set to 1 by
88 * default. Applied at the end of the scaling process.
94 /* Conversion function called once per channel */
95 float (*transform)(int s, int c, unsigned char* sample_data);
97 /* Function called once per sample */
98 int (*finalize)(int s, struct sensors_event_t* data);
103 char friendly_name[MAX_NAME_SIZE]; /* ex: Accelerometer */
104 char internal_name[MAX_NAME_SIZE]; /* ex: accel_3d */
105 char vendor_name[MAX_NAME_SIZE]; /* ex: Intel */
106 char init_trigger_name[MAX_NAME_SIZE]; /* ex: accel-name-dev1 */
107 char motion_trigger_name[MAX_NAME_SIZE];/* ex: accel-any-motion-dev1 */
113 * Currently active trigger - either a pointer to the initial (default)
114 * trigger name buffer, or a pointer to the motion trigger name buffer,
115 * or something else (typically NULL or a pointer to some static "\n".
116 * This is used to determine if the conditions are met to switch from
117 * the default trigger to the motion trigger for a sensor, or rather for
118 * the interrupt-driven sensors associated to a given iio device.
120 const char* selected_trigger;
122 float offset; /* (cooked = raw + offset) * scale */
123 float scale; /*default: 1. when set to 0, use channel specific value*/
124 float illumincalib; /* to set the calibration for the ALS */
126 float sampling_rate; /* requested events / second */
128 int dev_num; /* Associated iio dev num, ex: 3 for /dev/iio:device3 */
131 int catalog_index;/* Associated entry within the sensor_catalog array */
133 int num_channels; /* Actual channel count ; 0 for poll mode sensors */
136 * The array below indicates where to gather report data for this
137 * sensor inside the reports that we read from the iio character device.
138 * It is updated whenever channels are enabled or disabled on the same
139 * device. Channel size indicates the size in bytes of fields, and
140 * should be zero for disabled channels. The type field indicates how a
141 * specific channel data item is structured.
143 struct channel_info_t channel[MAX_CHANNELS];
146 * This flag is set if we acquired data from the sensor but did not
147 * forward it to upper layers (i.e. Android) yet. If so, report_buffer
148 * contains that data.
153 * Timestamp closely matching the date of sampling, preferably retrieved
154 * from a iio channel alongside sample data. Value zero indicates that
155 * we couldn't get such a closely correlated timestamp, and that one
156 * has to be generated before the report gets sent up to Android.
160 /* Buffer containing the last generated sensor report for this sensor */
161 unsigned char report_buffer[MAX_SENSOR_REPORT_SIZE];
163 /* Whether or not the above buffer contains data from a device report */
164 int report_initialized;
166 struct sample_ops_t ops;
168 int cal_level; /* 0 means not calibrated */
171 /* Filtering data for noisy sensors */
174 float prev_val; /* Previously reported value, for on-change sensors */
177 * Certain sensors expose their readings through sysfs files that have
178 * a long response time (100-200 ms for ALS). Rather than block our
179 * global control loop for several hundred ms each second, offload those
180 * lengthy blocking reads to dedicated threads, which will then report
181 * their data through a fd that we can add to our poll fd set.
183 int thread_data_fd[2];
184 pthread_t acquisition_thread;
186 /* For cal-uncal sensor pairs - index to the pair sensor in sensor_info */
189 uint32_t quirks; /* Bit mask expressing the need for special tweaks */
191 /* Note: we may have to explicitely serialize access to some fields */
195 * If the QUIRK_FIELD_ORDERING bit is set in quirks, the contents of
196 * this array are used in the finalization stage to swap sample fields
197 * before transmitting them to Android ; they form a mapping between
198 * the indices of the input and output arrays: ex: 0123 is identity for
199 * a sample containing 4 fields.
201 unsigned char order[MAX_CHANNELS];
203 /* A few variables used for data filtering */
204 float *history; /* Working buffer containing recorded samples */
205 int history_size; /* Number of recorded samples */
206 int history_entries; /* How many of these are initialized */
207 int history_index; /* Index of sample to evict next time */
210 /* Reference a few commonly used variables... */
211 extern int sensor_count;
212 extern struct sensor_t sensor_desc[MAX_SENSORS];
213 extern struct sensor_info_t sensor_info[MAX_SENSORS];
214 extern struct sensor_catalog_entry_t sensor_catalog[];