xref: /linux/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c (revision e7e2296b0ecf9b6e934f7a1118cee91d4d486a84)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2012 Invensense, Inc.
4 */
5 
6 #include <linux/pm_runtime.h>
7 
8 #include <linux/iio/common/inv_sensors_timestamp.h>
9 #include <linux/iio/events.h>
10 
11 #include "inv_mpu_iio.h"
12 
13 static unsigned int inv_scan_query_mpu6050(struct iio_dev *indio_dev)
14 {
15 	struct inv_mpu6050_state  *st = iio_priv(indio_dev);
16 	unsigned int mask;
17 
18 	/*
19 	 * If the MPU6050 is just used as a trigger, then the scan mask
20 	 * is not allocated so we simply enable the temperature channel
21 	 * as a dummy and bail out.
22 	 */
23 	if (!indio_dev->active_scan_mask) {
24 		st->chip_config.temp_fifo_enable = true;
25 		return INV_MPU6050_SENSOR_TEMP;
26 	}
27 
28 	st->chip_config.gyro_fifo_enable =
29 		test_bit(INV_MPU6050_SCAN_GYRO_X,
30 			 indio_dev->active_scan_mask) ||
31 		test_bit(INV_MPU6050_SCAN_GYRO_Y,
32 			 indio_dev->active_scan_mask) ||
33 		test_bit(INV_MPU6050_SCAN_GYRO_Z,
34 			 indio_dev->active_scan_mask);
35 
36 	st->chip_config.accl_fifo_enable =
37 		test_bit(INV_MPU6050_SCAN_ACCL_X,
38 			 indio_dev->active_scan_mask) ||
39 		test_bit(INV_MPU6050_SCAN_ACCL_Y,
40 			 indio_dev->active_scan_mask) ||
41 		test_bit(INV_MPU6050_SCAN_ACCL_Z,
42 			 indio_dev->active_scan_mask);
43 
44 	st->chip_config.temp_fifo_enable =
45 		test_bit(INV_MPU6050_SCAN_TEMP, indio_dev->active_scan_mask);
46 
47 	mask = 0;
48 	if (st->chip_config.gyro_fifo_enable)
49 		mask |= INV_MPU6050_SENSOR_GYRO;
50 	if (st->chip_config.accl_fifo_enable)
51 		mask |= INV_MPU6050_SENSOR_ACCL;
52 	if (st->chip_config.temp_fifo_enable)
53 		mask |= INV_MPU6050_SENSOR_TEMP;
54 
55 	return mask;
56 }
57 
58 static unsigned int inv_scan_query_mpu9x50(struct iio_dev *indio_dev)
59 {
60 	struct inv_mpu6050_state *st = iio_priv(indio_dev);
61 	unsigned int mask;
62 
63 	mask = inv_scan_query_mpu6050(indio_dev);
64 
65 	/* no magnetometer if i2c auxiliary bus is used */
66 	if (st->magn_disabled)
67 		return mask;
68 
69 	st->chip_config.magn_fifo_enable =
70 		test_bit(INV_MPU9X50_SCAN_MAGN_X,
71 			 indio_dev->active_scan_mask) ||
72 		test_bit(INV_MPU9X50_SCAN_MAGN_Y,
73 			 indio_dev->active_scan_mask) ||
74 		test_bit(INV_MPU9X50_SCAN_MAGN_Z,
75 			 indio_dev->active_scan_mask);
76 	if (st->chip_config.magn_fifo_enable)
77 		mask |= INV_MPU6050_SENSOR_MAGN;
78 
79 	return mask;
80 }
81 
82 static unsigned int inv_scan_query(struct iio_dev *indio_dev)
83 {
84 	struct inv_mpu6050_state *st = iio_priv(indio_dev);
85 
86 	switch (st->chip_type) {
87 	case INV_MPU9150:
88 	case INV_MPU9250:
89 	case INV_MPU9255:
90 		return inv_scan_query_mpu9x50(indio_dev);
91 	default:
92 		return inv_scan_query_mpu6050(indio_dev);
93 	}
94 }
95 
96 static unsigned int inv_compute_skip_samples(const struct inv_mpu6050_state *st)
97 {
98 	unsigned int skip_samples = 0;
99 
100 	/* mag first sample is always not ready, skip it */
101 	if (st->chip_config.magn_fifo_enable)
102 		skip_samples = 1;
103 
104 	return skip_samples;
105 }
106 
107 int inv_mpu6050_prepare_fifo(struct inv_mpu6050_state *st, bool enable)
108 {
109 	uint8_t d;
110 	int ret;
111 
112 	if (enable) {
113 		/* reset timestamping */
114 		inv_sensors_timestamp_reset(&st->timestamp);
115 		/* reset FIFO */
116 		d = st->chip_config.user_ctrl | INV_MPU6050_BIT_FIFO_RST;
117 		ret = regmap_write(st->map, st->reg->user_ctrl, d);
118 		if (ret)
119 			return ret;
120 		/* enable sensor output to FIFO */
121 		d = 0;
122 		if (st->chip_config.gyro_fifo_enable)
123 			d |= INV_MPU6050_BITS_GYRO_OUT;
124 		if (st->chip_config.accl_fifo_enable)
125 			d |= INV_MPU6050_BIT_ACCEL_OUT;
126 		if (st->chip_config.temp_fifo_enable)
127 			d |= INV_MPU6050_BIT_TEMP_OUT;
128 		if (st->chip_config.magn_fifo_enable)
129 			d |= INV_MPU6050_BIT_SLAVE_0;
130 		ret = regmap_write(st->map, st->reg->fifo_en, d);
131 		if (ret)
132 			return ret;
133 		/* enable FIFO reading */
134 		d = st->chip_config.user_ctrl | INV_MPU6050_BIT_FIFO_EN;
135 		ret = regmap_write(st->map, st->reg->user_ctrl, d);
136 		if (ret)
137 			return ret;
138 		/* enable data interrupt */
139 		ret = regmap_update_bits(st->map, st->reg->int_enable,
140 				INV_MPU6050_BIT_DATA_RDY_EN, INV_MPU6050_BIT_DATA_RDY_EN);
141 	} else {
142 		/* disable data interrupt */
143 		ret = regmap_update_bits(st->map, st->reg->int_enable,
144 				INV_MPU6050_BIT_DATA_RDY_EN, 0);
145 		if (ret)
146 			return ret;
147 		ret = regmap_write(st->map, st->reg->fifo_en, 0);
148 		if (ret)
149 			return ret;
150 		/* restore user_ctrl for disabling FIFO reading */
151 		ret = regmap_write(st->map, st->reg->user_ctrl,
152 				   st->chip_config.user_ctrl);
153 	}
154 
155 	return ret;
156 }
157 
158 /**
159  *  inv_mpu6050_set_enable() - enable chip functions.
160  *  @indio_dev:	Device driver instance.
161  *  @enable: enable/disable
162  */
163 static int inv_mpu6050_set_enable(struct iio_dev *indio_dev, bool enable)
164 {
165 	struct inv_mpu6050_state *st = iio_priv(indio_dev);
166 	struct device *pdev = regmap_get_device(st->map);
167 	unsigned int scan;
168 	int result;
169 
170 	if (enable) {
171 		scan = inv_scan_query(indio_dev);
172 		result = pm_runtime_resume_and_get(pdev);
173 		if (result)
174 			return result;
175 		/*
176 		 * In case autosuspend didn't trigger, turn off first not
177 		 * required sensors excepted WoM
178 		 */
179 		result = inv_mpu6050_switch_engine(st, false, ~scan & ~INV_MPU6050_SENSOR_WOM);
180 		if (result)
181 			goto error_power_off;
182 		result = inv_mpu6050_switch_engine(st, true, scan);
183 		if (result)
184 			goto error_power_off;
185 		st->skip_samples = inv_compute_skip_samples(st);
186 		result = inv_mpu6050_prepare_fifo(st, true);
187 		if (result)
188 			goto error_power_off;
189 	} else {
190 		st->chip_config.gyro_fifo_enable = 0;
191 		st->chip_config.accl_fifo_enable = 0;
192 		st->chip_config.temp_fifo_enable = 0;
193 		st->chip_config.magn_fifo_enable = 0;
194 		result = inv_mpu6050_prepare_fifo(st, false);
195 		if (result)
196 			goto error_power_off;
197 		pm_runtime_put_autosuspend(pdev);
198 	}
199 
200 	return 0;
201 
202 error_power_off:
203 	pm_runtime_put_autosuspend(pdev);
204 	return result;
205 }
206 
207 /**
208  * inv_mpu_data_rdy_trigger_set_state() - set data ready interrupt state
209  * @trig: Trigger instance
210  * @state: Desired trigger state
211  */
212 static int inv_mpu_data_rdy_trigger_set_state(struct iio_trigger *trig,
213 					      bool state)
214 {
215 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
216 	struct inv_mpu6050_state *st = iio_priv(indio_dev);
217 	int result;
218 
219 	mutex_lock(&st->lock);
220 	result = inv_mpu6050_set_enable(indio_dev, state);
221 	mutex_unlock(&st->lock);
222 
223 	return result;
224 }
225 
226 static const struct iio_trigger_ops inv_mpu_trigger_ops = {
227 	.set_trigger_state = &inv_mpu_data_rdy_trigger_set_state,
228 };
229 
230 static irqreturn_t inv_mpu6050_interrupt_timestamp(int irq, void *p)
231 {
232 	struct iio_dev *indio_dev = p;
233 	struct inv_mpu6050_state *st = iio_priv(indio_dev);
234 
235 	st->it_timestamp = iio_get_time_ns(indio_dev);
236 
237 	return IRQ_WAKE_THREAD;
238 }
239 
240 static irqreturn_t inv_mpu6050_interrupt_handle(int irq, void *p)
241 {
242 	struct iio_dev *indio_dev = p;
243 	struct inv_mpu6050_state *st = iio_priv(indio_dev);
244 	unsigned int int_status, wom_bits;
245 	u64 ev_code;
246 	int result;
247 
248 	switch (st->chip_type) {
249 	case INV_MPU6000:
250 	case INV_MPU6050:
251 	case INV_MPU9150:
252 		/*
253 		 * WoM is not supported and interrupt status read seems to be broken for
254 		 * some chips. Since data ready is the only interrupt, bypass interrupt
255 		 * status read and always assert data ready bit.
256 		 */
257 		wom_bits = 0;
258 		int_status = INV_MPU6050_BIT_RAW_DATA_RDY_INT;
259 		goto data_ready_interrupt;
260 	case INV_MPU6500:
261 	case INV_MPU6515:
262 	case INV_MPU6880:
263 	case INV_MPU9250:
264 	case INV_MPU9255:
265 		wom_bits = INV_MPU6500_BIT_WOM_INT;
266 		break;
267 	default:
268 		wom_bits = INV_ICM20608_BIT_WOM_INT;
269 		break;
270 	}
271 
272 	scoped_guard(mutex, &st->lock) {
273 		/* ack interrupt and check status */
274 		result = regmap_read(st->map, st->reg->int_status, &int_status);
275 		if (result) {
276 			dev_err(regmap_get_device(st->map), "failed to ack interrupt\n");
277 			return IRQ_HANDLED;
278 		}
279 
280 		/* handle WoM event */
281 		if (st->chip_config.wom_en && (int_status & wom_bits)) {
282 			ev_code = IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_X_OR_Y_OR_Z,
283 						     IIO_EV_TYPE_ROC, IIO_EV_DIR_RISING);
284 			iio_push_event(indio_dev, ev_code, st->it_timestamp);
285 		}
286 	}
287 
288 data_ready_interrupt:
289 	/* handle raw data interrupt */
290 	if (int_status & INV_MPU6050_BIT_RAW_DATA_RDY_INT) {
291 		indio_dev->pollfunc->timestamp = st->it_timestamp;
292 		iio_trigger_poll_nested(st->trig);
293 	}
294 
295 	return IRQ_HANDLED;
296 }
297 
298 int inv_mpu6050_probe_trigger(struct iio_dev *indio_dev, int irq_type)
299 {
300 	int ret;
301 	struct inv_mpu6050_state *st = iio_priv(indio_dev);
302 
303 	st->trig = devm_iio_trigger_alloc(&indio_dev->dev,
304 					  "%s-dev%d",
305 					  indio_dev->name,
306 					  iio_device_id(indio_dev));
307 	if (!st->trig)
308 		return -ENOMEM;
309 
310 	irq_type |= IRQF_ONESHOT;
311 	ret = devm_request_threaded_irq(&indio_dev->dev, st->irq,
312 					&inv_mpu6050_interrupt_timestamp,
313 					&inv_mpu6050_interrupt_handle,
314 					irq_type, "inv_mpu", indio_dev);
315 	if (ret)
316 		return ret;
317 
318 	st->trig->dev.parent = regmap_get_device(st->map);
319 	st->trig->ops = &inv_mpu_trigger_ops;
320 	iio_trigger_set_drvdata(st->trig, indio_dev);
321 
322 	ret = devm_iio_trigger_register(&indio_dev->dev, st->trig);
323 	if (ret)
324 		return ret;
325 
326 	indio_dev->trig = iio_trigger_get(st->trig);
327 
328 	return 0;
329 }
330