1 // SPDX-License-Identifier: GPL-2.0-only
34  * - get device out of low power mode,
35  * - setup hardware sampling period,
36  * - at end of period, upon data ready interrupt: pop pressure samples out of
38  * - when no longer needed, stop sampling process by putting device into
70 /* 200 ms should be enough for the longest conversion time in one-shot mode. */
78  * struct zpa2326_frequency - Hardware sampling frequency descriptor
102 		ARRAY_SIZE(zpa2326_sampling_frequencies) - 1];  in zpa2326_highest_frequency()
106  * struct zpa2326_private - Per-device internal private state
121  * @vref:       Power / voltage reference.
122  * @vdd:        Power supply.
133 	struct regulator               *vref;  member
138 	dev_err(idev->dev.parent, fmt "\n", ##__VA_ARGS__)
141 	dev_warn(idev->dev.parent, fmt "\n", ##__VA_ARGS__)
144 	dev_dbg(idev->dev.parent, fmt "\n", ##__VA_ARGS__)
210  * zpa2326_enable_device() - Enable device, i.e. get out of low power mode.
223 			    iio_priv(indio_dev))->regmap,  in zpa2326_enable_device()
236  * zpa2326_sleep() - Disable device, i.e. switch to low power mode.
249 			    iio_priv(indio_dev))->regmap,  in zpa2326_sleep()
262  * zpa2326_reset_device() - Reset device to default hardware state.
275 			    iio_priv(indio_dev))->regmap,  in zpa2326_reset_device()
290  * zpa2326_start_oneshot() - Start a single sampling cycle, i.e. in one shot
304 			    iio_priv(indio_dev))->regmap,  in zpa2326_start_oneshot()
320  * zpa2326_power_on() - Power on device to allow subsequent configuration.
336 	err = regulator_enable(private->vref);  in zpa2326_power_on()
340 	err = regulator_enable(private->vdd);  in zpa2326_power_on()
342 		goto vref;  in zpa2326_power_on()
359 	regulator_disable(private->vdd);  in zpa2326_power_on()
360 vref:  in zpa2326_power_on()
361 	regulator_disable(private->vref);  in zpa2326_power_on()
369  * zpa2326_power_off() - Power off device, i.e. disable attached power
379 	regulator_disable(private->vdd);  in zpa2326_power_off()
380 	regulator_disable(private->vref);  in zpa2326_power_off()
386  * zpa2326_config_oneshot() - Setup device for one shot / on demand mode.
406 						iio_priv(indio_dev))->regmap;  in zpa2326_config_oneshot()
411 	err = regmap_write(regs, ZPA2326_CTRL_REG3_REG, freq->odr);  in zpa2326_config_oneshot()
421 			dev_err(indio_dev->dev.parent,  in zpa2326_config_oneshot()
427 	zpa2326_dbg(indio_dev, "one shot mode setup @%dHz", freq->hz);  in zpa2326_config_oneshot()
433  * zpa2326_clear_fifo() - Clear remaining entries in hardware FIFO.
448 			       iio_priv(indio_dev))->regmap;  in zpa2326_clear_fifo()
482 			min_count--;  in zpa2326_clear_fifo()
503  * zpa2326_dequeue_pressure() - Retrieve the most recent pressure sample from
516 			       iio_priv(indio_dev))->regmap;  in zpa2326_dequeue_pressure()
519 	int            cleared = -1;  in zpa2326_dequeue_pressure()
541 		return zpa2326_clear_fifo(indio_dev, ZPA2326_FIFO_DEPTH - 1);  in zpa2326_dequeue_pressure()
573  * zpa2326_fill_sample_buffer() - Enqueue new channel samples to IIO buffer.
591 	if (test_bit(0, indio_dev->active_scan_mask)) {  in zpa2326_fill_sample_buffer()
601 	if (test_bit(1, indio_dev->active_scan_mask)) {  in zpa2326_fill_sample_buffer()
603 		err = regmap_bulk_read(private->regmap, ZPA2326_TEMP_OUT_L_REG,  in zpa2326_fill_sample_buffer()
614 	 *   - by hardware interrupt handler if interrupt is available: see  in zpa2326_fill_sample_buffer()
616 	 *   - or oneshot completion polling machinery : see  in zpa2326_fill_sample_buffer()
622 					   private->timestamp);  in zpa2326_fill_sample_buffer()
634 		return -EAGAIN;  in zpa2326_runtime_suspend()
657  * zpa2326_resume() - Request the PM layer to power supply the device.
661  *  < 0 - a negative error code meaning failure ;
662  *    0 - success, device has just been powered up ;
663  *    1 - success, device was already powered.
669 	err = pm_runtime_get_sync(indio_dev->dev.parent);  in zpa2326_resume()
671 		pm_runtime_put(indio_dev->dev.parent);  in zpa2326_resume()
689  * zpa2326_suspend() - Schedule a power down using autosuspend feature of PM
698 	struct device *parent = indio_dev->dev.parent;  in zpa2326_suspend()
740  * zpa2326_handle_irq() - Process hardware interrupts.
756 		 iio_priv(indio_dev))->timestamp = iio_get_time_ns(indio_dev);  in zpa2326_handle_irq()
763  * zpa2326_handle_threaded_irq() - Interrupt bottom-half handler.
778  * configured in one-shot mode either by an external trigger or the IIO read_raw
785  *   %IRQ_NONE - no consistent interrupt happened ;
786  *   %IRQ_HANDLED - there was new samples available.
805 	 * status de-asserts interrupt line.  in zpa2326_handle_threaded_irq()
807 	priv->result = regmap_read(priv->regmap, ZPA2326_INT_SOURCE_REG, &val);  in zpa2326_handle_threaded_irq()
808 	if (priv->result < 0) {  in zpa2326_handle_threaded_irq()
829 		priv->result = -ENODATA;  in zpa2326_handle_threaded_irq()
834 	iio_trigger_poll_nested(priv->trigger);  in zpa2326_handle_threaded_irq()
850 	complete(&priv->data_ready);  in zpa2326_handle_threaded_irq()
856  * zpa2326_wait_oneshot_completion() - Wait for oneshot data ready interrupt.
871 		&private->data_ready, ZPA2326_CONVERSION_JIFFIES);  in zpa2326_wait_oneshot_completion()
877 		return private->result;  in zpa2326_wait_oneshot_completion()
880 	regmap_read(private->regmap, ZPA2326_INT_SOURCE_REG, &val);  in zpa2326_wait_oneshot_completion()
886 		return -ETIME;  in zpa2326_wait_oneshot_completion()
890 	return -ERESTARTSYS;  in zpa2326_wait_oneshot_completion()
900 	private->irq = irq;  in zpa2326_init_managed_irq()
911 	init_completion(&private->data_ready);  in zpa2326_init_managed_irq()
930  * zpa2326_poll_oneshot_completion() - Actively poll for one shot data ready.
942 			       iio_priv(indio_dev))->regmap;  in zpa2326_poll_oneshot_completion()
949 	 * At least, 100 ms is needed for the device to complete its one-shot  in zpa2326_poll_oneshot_completion()
953 		return -ERESTARTSYS;  in zpa2326_poll_oneshot_completion()
962 			/* One-shot bit self clears at conversion end. */  in zpa2326_poll_oneshot_completion()
967 			err = -ETIME;  in zpa2326_poll_oneshot_completion()
985 		err = -ENODATA;  in zpa2326_poll_oneshot_completion()
998  * zpa2326_fetch_raw_sample() - Retrieve a raw sample and convert it to CPU
1011 			       iio_priv(indio_dev))->regmap;  in zpa2326_fetch_raw_sample()
1040 		/* Temperature is a 16 bits wide little-endian signed int. */  in zpa2326_fetch_raw_sample()
1046 		return -EINVAL;  in zpa2326_fetch_raw_sample()
1051  * zpa2326_sample_oneshot() - Perform a complete one shot sampling cycle.
1098 		ret = zpa2326_config_oneshot(indio_dev, priv->irq);  in zpa2326_sample_oneshot()
1109 	if (priv->irq > 0)  in zpa2326_sample_oneshot()
1129  * zpa2326_trigger_handler() - Perform an IIO buffered sampling round in one
1135  * Bottom-half handler called by the IIO trigger to which our device is
1152  *   %IRQ_NONE - no consistent interrupt happened ;
1153  *   %IRQ_HANDLED - there was new samples available.
1158 					     data)->indio_dev;  in zpa2326_trigger_handler()
1175 		if (priv->irq <= 0) {  in zpa2326_trigger_handler()
1181 			priv->timestamp = iio_get_time_ns(indio_dev);  in zpa2326_trigger_handler()
1198 	iio_trigger_notify_done(indio_dev->trig);  in zpa2326_trigger_handler()
1204  * zpa2326_preenable_buffer() - Prepare device for configuring triggered
1223 	 iio_priv(indio_dev))->waken = iio_priv(indio_dev);  in zpa2326_preenable_buffer()
1229  * zpa2326_postenable_buffer() - Configure device for triggered sampling.
1232  * Basically setup one-shot mode if plugging external trigger.
1249 	if (!priv->waken) {  in zpa2326_postenable_buffer()
1262 	if (!iio_trigger_using_own(indio_dev) && priv->waken) {  in zpa2326_postenable_buffer()
1265 		 * powered up: reconfigure one-shot mode.  in zpa2326_postenable_buffer()
1267 		err = zpa2326_config_oneshot(indio_dev, priv->irq);  in zpa2326_postenable_buffer()
1292  * zpa2326_set_trigger_state() - Start / stop continuous sampling.
1306 							trig->dev.parent);  in zpa2326_set_trigger_state()
1325 		disable_irq(priv->irq);  in zpa2326_set_trigger_state()
1331 		err = regmap_write(priv->regmap, ZPA2326_CTRL_REG3_REG,  in zpa2326_set_trigger_state()
1332 				   zpa2326_highest_frequency()->odr);  in zpa2326_set_trigger_state()
1341 		err = regmap_read(priv->regmap, ZPA2326_INT_SOURCE_REG, &val);  in zpa2326_set_trigger_state()
1346 		 * Re-enable interrupts only if we can guarantee the device will  in zpa2326_set_trigger_state()
1350 		enable_irq(priv->irq);  in zpa2326_set_trigger_state()
1359 		if (priv->waken) {  in zpa2326_set_trigger_state()
1361 			err = regmap_write(priv->regmap, ZPA2326_CTRL_REG1_REG,  in zpa2326_set_trigger_state()
1369 		err = regmap_write(priv->regmap, ZPA2326_CTRL_REG3_REG,  in zpa2326_set_trigger_state()
1371 				   priv->frequency->odr);  in zpa2326_set_trigger_state()
1376 			    priv->frequency->hz);  in zpa2326_set_trigger_state()
1387  * zpa2326_init_managed_trigger() - Create interrupt driven / hardware trigger
1412 	trigger = devm_iio_trigger_alloc(parent, "%s-dev%d",  in zpa2326_init_managed_trigger()
1413 					 indio_dev->name,  in zpa2326_init_managed_trigger()
1416 		return -ENOMEM;  in zpa2326_init_managed_trigger()
1419 	trigger->ops = &zpa2326_trigger_ops;  in zpa2326_init_managed_trigger()
1421 	private->trigger = trigger;  in zpa2326_init_managed_trigger()
1434 	return ((struct zpa2326_private *)iio_priv(indio_dev))->frequency->hz;  in zpa2326_get_frequency()
1448 		return -EINVAL;  in zpa2326_set_frequency()
1455 	priv->frequency = &zpa2326_sampling_frequencies[freq];  in zpa2326_set_frequency()
1482 		return zpa2326_sample_oneshot(indio_dev, chan->type, val);  in zpa2326_read_raw()
1485 		switch (chan->type) {  in zpa2326_read_raw()
1498 			 *     Temp[degC] = Tempcode * 0.00649 - 176.83  in zpa2326_read_raw()
1502 			 * Hence, to produce a temperature in milli-degrees  in zpa2326_read_raw()
1507 			 *     Offset = -176.83 / 0.00649  in zpa2326_read_raw()
1515 			return -EINVAL;  in zpa2326_read_raw()
1519 		switch (chan->type) {  in zpa2326_read_raw()
1521 			*val = -17683000;  in zpa2326_read_raw()
1526 			return -EINVAL;  in zpa2326_read_raw()
1534 		return -EINVAL;  in zpa2326_read_raw()
1545 		return -EINVAL;  in zpa2326_write_raw()
1600 	indio_dev->modes = INDIO_DIRECT_MODE;  in zpa2326_create_managed_iiodev()
1601 	indio_dev->channels = zpa2326_channels;  in zpa2326_create_managed_iiodev()
1602 	indio_dev->num_channels = ARRAY_SIZE(zpa2326_channels);  in zpa2326_create_managed_iiodev()
1603 	indio_dev->name = name;  in zpa2326_create_managed_iiodev()
1604 	indio_dev->info = &zpa2326_info;  in zpa2326_create_managed_iiodev()
1622 		return -ENOMEM;  in zpa2326_probe()
1626 	priv->vref = devm_regulator_get(parent, "vref");  in zpa2326_probe()
1627 	if (IS_ERR(priv->vref))  in zpa2326_probe()
1628 		return PTR_ERR(priv->vref);  in zpa2326_probe()
1630 	priv->vdd = devm_regulator_get(parent, "vdd");  in zpa2326_probe()
1631 	if (IS_ERR(priv->vdd))  in zpa2326_probe()
1632 		return PTR_ERR(priv->vdd);  in zpa2326_probe()
1635 	priv->frequency = zpa2326_highest_frequency();  in zpa2326_probe()
1642 	priv->regmap = regmap;  in zpa2326_probe()
1670 		err = -ENODEV;  in zpa2326_probe()
1710 	zpa2326_fini_runtime(indio_dev->dev.parent);  in zpa2326_remove()