xref: /openbmc/linux/include/linux/input/adxl34x.h (revision 95e9fd10)
1 /*
2  * include/linux/input/adxl34x.h
3  *
4  * Digital Accelerometer characteristics are highly application specific
5  * and may vary between boards and models. The platform_data for the
6  * device's "struct device" holds this information.
7  *
8  * Copyright 2009 Analog Devices Inc.
9  *
10  * Licensed under the GPL-2 or later.
11  */
12 
13 #ifndef __LINUX_INPUT_ADXL34X_H__
14 #define __LINUX_INPUT_ADXL34X_H__
15 
16 struct adxl34x_platform_data {
17 
18 	/*
19 	 * X,Y,Z Axis Offset:
20 	 * offer user offset adjustments in twoscompliment
21 	 * form with a scale factor of 15.6 mg/LSB (i.e. 0x7F = +2 g)
22 	 */
23 
24 	s8 x_axis_offset;
25 	s8 y_axis_offset;
26 	s8 z_axis_offset;
27 
28 	/*
29 	 * TAP_X/Y/Z Enable: Setting TAP_X, Y, or Z Enable enables X,
30 	 * Y, or Z participation in Tap detection. A '0' excludes the
31 	 * selected axis from participation in Tap detection.
32 	 * Setting the SUPPRESS bit suppresses Double Tap detection if
33 	 * acceleration greater than tap_threshold is present during the
34 	 * tap_latency period, i.e. after the first tap but before the
35 	 * opening of the second tap window.
36 	 */
37 
38 #define ADXL_SUPPRESS	(1 << 3)
39 #define ADXL_TAP_X_EN	(1 << 2)
40 #define ADXL_TAP_Y_EN	(1 << 1)
41 #define ADXL_TAP_Z_EN	(1 << 0)
42 
43 	u8 tap_axis_control;
44 
45 	/*
46 	 * tap_threshold:
47 	 * holds the threshold value for tap detection/interrupts.
48 	 * The data format is unsigned. The scale factor is 62.5 mg/LSB
49 	 * (i.e. 0xFF = +16 g). A zero value may result in undesirable
50 	 * behavior if Tap/Double Tap is enabled.
51 	 */
52 
53 	u8 tap_threshold;
54 
55 	/*
56 	 * tap_duration:
57 	 * is an unsigned time value representing the maximum
58 	 * time that an event must be above the tap_threshold threshold
59 	 * to qualify as a tap event. The scale factor is 625 us/LSB. A zero
60 	 * value will prevent Tap/Double Tap functions from working.
61 	 */
62 
63 	u8 tap_duration;
64 
65 	/*
66 	 * tap_latency:
67 	 * is an unsigned time value representing the wait time
68 	 * from the detection of a tap event to the opening of the time
69 	 * window tap_window for a possible second tap event. The scale
70 	 * factor is 1.25 ms/LSB. A zero value will disable the Double Tap
71 	 * function.
72 	 */
73 
74 	u8 tap_latency;
75 
76 	/*
77 	 * tap_window:
78 	 * is an unsigned time value representing the amount
79 	 * of time after the expiration of tap_latency during which a second
80 	 * tap can begin. The scale factor is 1.25 ms/LSB. A zero value will
81 	 * disable the Double Tap function.
82 	 */
83 
84 	u8 tap_window;
85 
86 	/*
87 	 * act_axis_control:
88 	 * X/Y/Z Enable: A '1' enables X, Y, or Z participation in activity
89 	 * or inactivity detection. A '0' excludes the selected axis from
90 	 * participation. If all of the axes are excluded, the function is
91 	 * disabled.
92 	 * AC/DC: A '0' = DC coupled operation and a '1' = AC coupled
93 	 * operation. In DC coupled operation, the current acceleration is
94 	 * compared with activity_threshold and inactivity_threshold directly
95 	 * to determine whether activity or inactivity is detected. In AC
96 	 * coupled operation for activity detection, the acceleration value
97 	 * at the start of activity detection is taken as a reference value.
98 	 * New samples of acceleration are then compared to this
99 	 * reference value and if the magnitude of the difference exceeds
100 	 * activity_threshold the device will trigger an activity interrupt. In
101 	 * AC coupled operation for inactivity detection, a reference value
102 	 * is used again for comparison and is updated whenever the
103 	 * device exceeds the inactivity threshold. Once the reference
104 	 * value is selected, the device compares the magnitude of the
105 	 * difference between the reference value and the current
106 	 * acceleration with inactivity_threshold. If the difference is below
107 	 * inactivity_threshold for a total of inactivity_time, the device is
108 	 * considered inactive and the inactivity interrupt is triggered.
109 	 */
110 
111 #define ADXL_ACT_ACDC		(1 << 7)
112 #define ADXL_ACT_X_EN		(1 << 6)
113 #define ADXL_ACT_Y_EN		(1 << 5)
114 #define ADXL_ACT_Z_EN		(1 << 4)
115 #define ADXL_INACT_ACDC		(1 << 3)
116 #define ADXL_INACT_X_EN		(1 << 2)
117 #define ADXL_INACT_Y_EN		(1 << 1)
118 #define ADXL_INACT_Z_EN		(1 << 0)
119 
120 	u8 act_axis_control;
121 
122 	/*
123 	 * activity_threshold:
124 	 * holds the threshold value for activity detection.
125 	 * The data format is unsigned. The scale factor is
126 	 * 62.5 mg/LSB. A zero value may result in undesirable behavior if
127 	 * Activity interrupt is enabled.
128 	 */
129 
130 	u8 activity_threshold;
131 
132 	/*
133 	 * inactivity_threshold:
134 	 * holds the threshold value for inactivity
135 	 * detection. The data format is unsigned. The scale
136 	 * factor is 62.5 mg/LSB. A zero value may result in undesirable
137 	 * behavior if Inactivity interrupt is enabled.
138 	 */
139 
140 	u8 inactivity_threshold;
141 
142 	/*
143 	 * inactivity_time:
144 	 * is an unsigned time value representing the
145 	 * amount of time that acceleration must be below the value in
146 	 * inactivity_threshold for inactivity to be declared. The scale factor
147 	 * is 1 second/LSB. Unlike the other interrupt functions, which
148 	 * operate on unfiltered data, the inactivity function operates on the
149 	 * filtered output data. At least one output sample must be
150 	 * generated for the inactivity interrupt to be triggered. This will
151 	 * result in the function appearing un-responsive if the
152 	 * inactivity_time register is set with a value less than the time
153 	 * constant of the Output Data Rate. A zero value will result in an
154 	 * interrupt when the output data is below inactivity_threshold.
155 	 */
156 
157 	u8 inactivity_time;
158 
159 	/*
160 	 * free_fall_threshold:
161 	 * holds the threshold value for Free-Fall detection.
162 	 * The data format is unsigned. The root-sum-square(RSS) value
163 	 * of all axes is calculated and compared to the value in
164 	 * free_fall_threshold to determine if a free fall event may be
165 	 * occurring.  The scale factor is 62.5 mg/LSB. A zero value may
166 	 * result in undesirable behavior if Free-Fall interrupt is
167 	 * enabled. Values between 300 and 600 mg (0x05 to 0x09) are
168 	 * recommended.
169 	 */
170 
171 	u8 free_fall_threshold;
172 
173 	/*
174 	 * free_fall_time:
175 	 * is an unsigned time value representing the minimum
176 	 * time that the RSS value of all axes must be less than
177 	 * free_fall_threshold to generate a Free-Fall interrupt. The
178 	 * scale factor is 5 ms/LSB. A zero value may result in
179 	 * undesirable behavior if Free-Fall interrupt is enabled.
180 	 * Values between 100 to 350 ms (0x14 to 0x46) are recommended.
181 	 */
182 
183 	u8 free_fall_time;
184 
185 	/*
186 	 * data_rate:
187 	 * Selects device bandwidth and output data rate.
188 	 * RATE = 3200 Hz / (2^(15 - x)). Default value is 0x0A, or 100 Hz
189 	 * Output Data Rate. An Output Data Rate should be selected that
190 	 * is appropriate for the communication protocol and frequency
191 	 * selected. Selecting too high of an Output Data Rate with a low
192 	 * communication speed will result in samples being discarded.
193 	 */
194 
195 	u8 data_rate;
196 
197 	/*
198 	 * data_range:
199 	 * FULL_RES: When this bit is set with the device is
200 	 * in Full-Resolution Mode, where the output resolution increases
201 	 * with RANGE to maintain a 4 mg/LSB scale factor. When this
202 	 * bit is cleared the device is in 10-bit Mode and RANGE determine the
203 	 * maximum g-Range and scale factor.
204 	 */
205 
206 #define ADXL_FULL_RES		(1 << 3)
207 #define ADXL_RANGE_PM_2g	0
208 #define ADXL_RANGE_PM_4g	1
209 #define ADXL_RANGE_PM_8g	2
210 #define ADXL_RANGE_PM_16g	3
211 
212 	u8 data_range;
213 
214 	/*
215 	 * low_power_mode:
216 	 * A '0' = Normal operation and a '1' = Reduced
217 	 * power operation with somewhat higher noise.
218 	 */
219 
220 	u8 low_power_mode;
221 
222 	/*
223 	 * power_mode:
224 	 * LINK: A '1' with both the activity and inactivity functions
225 	 * enabled will delay the start of the activity function until
226 	 * inactivity is detected. Once activity is detected, inactivity
227 	 * detection will begin and prevent the detection of activity. This
228 	 * bit serially links the activity and inactivity functions. When '0'
229 	 * the inactivity and activity functions are concurrent. Additional
230 	 * information can be found in the ADXL34x datasheet's Application
231 	 * section under Link Mode.
232 	 * AUTO_SLEEP: A '1' sets the ADXL34x to switch to Sleep Mode
233 	 * when inactivity (acceleration has been below inactivity_threshold
234 	 * for at least inactivity_time) is detected and the LINK bit is set.
235 	 * A '0' disables automatic switching to Sleep Mode. See the
236 	 * Sleep Bit section of the ADXL34x datasheet for more information.
237 	 */
238 
239 #define ADXL_LINK	(1 << 5)
240 #define ADXL_AUTO_SLEEP	(1 << 4)
241 
242 	u8 power_mode;
243 
244 	/*
245 	 * fifo_mode:
246 	 * BYPASS The FIFO is bypassed
247 	 * FIFO   FIFO collects up to 32 values then stops collecting data
248 	 * STREAM FIFO holds the last 32 data values. Once full, the FIFO's
249 	 *        oldest data is lost as it is replaced with newer data
250 	 *
251 	 * DEFAULT should be ADXL_FIFO_STREAM
252 	 */
253 
254 #define ADXL_FIFO_BYPASS	0
255 #define ADXL_FIFO_FIFO		1
256 #define ADXL_FIFO_STREAM	2
257 
258 	u8 fifo_mode;
259 
260 	/*
261 	 * watermark:
262 	 * The Watermark feature can be used to reduce the interrupt load
263 	 * of the system. The FIFO fills up to the value stored in watermark
264 	 * [1..32] and then generates an interrupt.
265 	 * A '0' disables the watermark feature.
266 	 */
267 
268 	u8 watermark;
269 
270 	/*
271 	 * When acceleration measurements are received from the ADXL34x
272 	 * events are sent to the event subsystem. The following settings
273 	 * select the event type and event code for new x, y and z axis data
274 	 * respectively.
275 	 */
276 	u32 ev_type;	/* EV_ABS or EV_REL */
277 
278 	u32 ev_code_x;	/* ABS_X,Y,Z or REL_X,Y,Z */
279 	u32 ev_code_y;	/* ABS_X,Y,Z or REL_X,Y,Z */
280 	u32 ev_code_z;	/* ABS_X,Y,Z or REL_X,Y,Z */
281 
282 	/*
283 	 * A valid BTN or KEY Code; use tap_axis_control to disable
284 	 * event reporting
285 	 */
286 
287 	u32 ev_code_tap[3];	/* EV_KEY {X-Axis, Y-Axis, Z-Axis} */
288 
289 	/*
290 	 * A valid BTN or KEY Code for Free-Fall or Activity enables
291 	 * input event reporting. A '0' disables the Free-Fall or
292 	 * Activity reporting.
293 	 */
294 
295 	u32 ev_code_ff;	/* EV_KEY */
296 	u32 ev_code_act_inactivity;	/* EV_KEY */
297 
298 	/*
299 	 * Use ADXL34x INT2 pin instead of INT1 pin for interrupt output
300 	 */
301 	u8 use_int2;
302 
303 	/*
304 	 * ADXL346 only ORIENTATION SENSING feature
305 	 * The orientation function of the ADXL346 reports both 2-D and
306 	 * 3-D orientation concurrently.
307 	 */
308 
309 #define ADXL_EN_ORIENTATION_2D		1
310 #define ADXL_EN_ORIENTATION_3D		2
311 #define ADXL_EN_ORIENTATION_2D_3D	3
312 
313 	u8 orientation_enable;
314 
315 	/*
316 	 * The width of the deadzone region between two or more
317 	 * orientation positions is determined by setting the Deadzone
318 	 * value. The deadzone region size can be specified with a
319 	 * resolution of 3.6deg. The deadzone angle represents the total
320 	 * angle where the orientation is considered invalid.
321 	 */
322 
323 #define ADXL_DEADZONE_ANGLE_0p0		0	/* !!!0.0 [deg] */
324 #define ADXL_DEADZONE_ANGLE_3p6		1	/* 3.6 [deg] */
325 #define ADXL_DEADZONE_ANGLE_7p2		2	/* 7.2 [deg] */
326 #define ADXL_DEADZONE_ANGLE_10p8	3	/* 10.8 [deg] */
327 #define ADXL_DEADZONE_ANGLE_14p4	4	/* 14.4 [deg] */
328 #define ADXL_DEADZONE_ANGLE_18p0	5	/* 18.0 [deg] */
329 #define ADXL_DEADZONE_ANGLE_21p6	6	/* 21.6 [deg] */
330 #define ADXL_DEADZONE_ANGLE_25p2	7	/* 25.2 [deg] */
331 
332 	u8 deadzone_angle;
333 
334 	/*
335 	 * To eliminate most human motion such as walking or shaking,
336 	 * a Divisor value should be selected to effectively limit the
337 	 * orientation bandwidth. Set the depth of the filter used to
338 	 * low-pass filter the measured acceleration for stable
339 	 * orientation sensing
340 	 */
341 
342 #define ADXL_LP_FILTER_DIVISOR_2	0
343 #define ADXL_LP_FILTER_DIVISOR_4	1
344 #define ADXL_LP_FILTER_DIVISOR_8	2
345 #define ADXL_LP_FILTER_DIVISOR_16	3
346 #define ADXL_LP_FILTER_DIVISOR_32	4
347 #define ADXL_LP_FILTER_DIVISOR_64	5
348 #define ADXL_LP_FILTER_DIVISOR_128	6
349 #define ADXL_LP_FILTER_DIVISOR_256	7
350 
351 	u8 divisor_length;
352 
353 	u32 ev_codes_orient_2d[4];	/* EV_KEY {+X, -X, +Y, -Y} */
354 	u32 ev_codes_orient_3d[6];	/* EV_KEY {+Z, +Y, +X, -X, -Y, -Z} */
355 };
356 #endif
357