iio/adc/twl6030-gpadc.c

1 // SPDX-License-Identifier: GPL-2.0-only
5  * Copyright (C) 2009-2013 Texas Instruments Inc.
13  * Based on twl4030-madc.c
74  * struct twl6030_chnl_calib - channel calibration
77  * @offset_error:	offset of the real curve
86  * struct twl6030_ideal_code - GPADC calibration parameters
88  * to the and of the measurable input range
92  * @code2:	ideal code for at the end of the range
94  * @volt2:	voltage input at the end(high voltage)
107  * struct twl6030_gpadc_platform_data - platform specific data
108  * @nchannels:		number of GPADC channels
111  * @start_conversion:	pointer to ADC start conversion function
113  *			register address for reading conversion result
126  * struct twl6030_gpadc_data - GPADC data
129  * @irq_complete:	completion to signal end of conversion
323 	[11] = { /* ch 11, internal, VBUS DC-DC output current */
387 	complete(&gpadc->irq_complete);  in twl6030_gpadc_irq_handler()
418 	 * for any prior chosen channel, when the conversion is ready  in twl6032_channel_to_reg()
440 	const struct twl6030_ideal_code *ideal = pdata->ideal;  in twl6030_channel_calibrated()
443 	i = twl6030_gpadc_lookup(ideal, channel, pdata->nchannels);  in twl6030_channel_calibrated()
445 	return pdata->ideal[i].code2;  in twl6030_channel_calibrated()
451 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;  in twl6030_gpadc_make_correction()
455 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);  in twl6030_gpadc_make_correction()
456 	corrected_code = ((raw_code * 1000) -  in twl6030_gpadc_make_correction()
457 		gpadc->twl6030_cal_tbl[i].offset_error) /  in twl6030_gpadc_make_correction()
458 		gpadc->twl6030_cal_tbl[i].gain_error;  in twl6030_gpadc_make_correction()
466 	u8 reg = gpadc->pdata->channel_to_reg(channel);  in twl6030_gpadc_get_raw()
473 		dev_dbg(gpadc->dev, "unable to read register 0x%X\n", reg);  in twl6030_gpadc_get_raw()
478 	dev_dbg(gpadc->dev, "GPADC raw code: %d", raw_code);  in twl6030_gpadc_get_raw()
480 	if (twl6030_channel_calibrated(gpadc->pdata, channel))  in twl6030_gpadc_get_raw()
491 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;  in twl6030_gpadc_get_processed()
501 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);  in twl6030_gpadc_get_processed()
503 			gpadc->twl6030_cal_tbl[i].gain;  in twl6030_gpadc_get_processed()
508 	dev_dbg(gpadc->dev, "GPADC corrected code: %d", corrected_code);  in twl6030_gpadc_get_processed()
509 	dev_dbg(gpadc->dev, "GPADC value: %d", channel_value);  in twl6030_gpadc_get_processed()
524 	mutex_lock(&gpadc->lock);  in twl6030_gpadc_read_raw()
526 	ret = gpadc->pdata->start_conversion(chan->channel);  in twl6030_gpadc_read_raw()
528 		dev_err(gpadc->dev, "failed to start conversion\n");  in twl6030_gpadc_read_raw()
531 	/* wait for conversion to complete */  in twl6030_gpadc_read_raw()
533 				&gpadc->irq_complete, msecs_to_jiffies(5000));  in twl6030_gpadc_read_raw()
535 		ret = -ETIMEDOUT;  in twl6030_gpadc_read_raw()
538 		ret = -EINTR;  in twl6030_gpadc_read_raw()
544 		ret = twl6030_gpadc_get_raw(gpadc, chan->channel, val);  in twl6030_gpadc_read_raw()
545 		ret = ret ? -EIO : IIO_VAL_INT;  in twl6030_gpadc_read_raw()
549 		ret = twl6030_gpadc_get_processed(gpadc, chan->channel, val);  in twl6030_gpadc_read_raw()
550 		ret = ret ? -EIO : IIO_VAL_INT;  in twl6030_gpadc_read_raw()
557 	mutex_unlock(&gpadc->lock);  in twl6030_gpadc_read_raw()
568  * The goal is to find offset and gain of the real curve for each calibrated
570  * gain: k = 1 + ((d2 - d1) / (x2 - x1))
571  * offset: b = d1 + (k - 1) * x1
577 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;  in twl6030_calibrate_channel()
579 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);  in twl6030_calibrate_channel()
582 	gain = ((ideal[i].volt2 - ideal[i].volt1) * 1000) /  in twl6030_calibrate_channel()
583 		(ideal[i].code2 - ideal[i].code1);  in twl6030_calibrate_channel()
588 	/* k - real curve gain */  in twl6030_calibrate_channel()
589 	k = 1000 + (((d2 - d1) * 1000) / (x2 - x1));  in twl6030_calibrate_channel()
591 	/* b - offset of the real curve gain */  in twl6030_calibrate_channel()
592 	b = (d1 * 1000) - (k - 1000) * x1;  in twl6030_calibrate_channel()
594 	gpadc->twl6030_cal_tbl[i].gain = gain;  in twl6030_calibrate_channel()
595 	gpadc->twl6030_cal_tbl[i].gain_error = k;  in twl6030_calibrate_channel()
596 	gpadc->twl6030_cal_tbl[i].offset_error = b;  in twl6030_calibrate_channel()
598 	dev_dbg(gpadc->dev, "GPADC d1   for Chn: %d = %d\n", channel, d1);  in twl6030_calibrate_channel()
599 	dev_dbg(gpadc->dev, "GPADC d2   for Chn: %d = %d\n", channel, d2);  in twl6030_calibrate_channel()
600 	dev_dbg(gpadc->dev, "GPADC x1   for Chn: %d = %d\n", channel, x1);  in twl6030_calibrate_channel()
601 	dev_dbg(gpadc->dev, "GPADC x2   for Chn: %d = %d\n", channel, x2);  in twl6030_calibrate_channel()
602 	dev_dbg(gpadc->dev, "GPADC Gain for Chn: %d = %d\n", channel, gain);  in twl6030_calibrate_channel()
603 	dev_dbg(gpadc->dev, "GPADC k    for Chn: %d = %d\n", channel, k);  in twl6030_calibrate_channel()
604 	dev_dbg(gpadc->dev, "GPADC b    for Chn: %d = %d\n", channel, b);  in twl6030_calibrate_channel()
611 	 * bit 0 - sign, bit 7 - reserved, 6..1 - trim value  in twl6030_gpadc_get_trim_offset()
613 	 * is absolute value, the correct conversion results are  in twl6030_gpadc_get_trim_offset()
638 		dev_err(gpadc->dev, "calibration failed\n");  in twl6030_calibration()
703 		val = -val;  in twl6032_get_trim_value()
717 		dev_err(gpadc->dev, "calibration failed\n");  in twl6032_calibration()
779 				d1 = -d1;  in twl6032_calibration()
787 				d2 = -d2;  in twl6032_calibration()
867 		.compatible = "ti,twl6030-gpadc",
871 		.compatible = "ti,twl6032-gpadc",
874 	{ /* end */ }
876 MODULE_DEVICE_TABLE(of, of_twl6030_match_tbl);
880 	struct device *dev = &pdev->dev;  in twl6030_gpadc_probe()
887 	pdata = device_get_match_data(&pdev->dev);  in twl6030_gpadc_probe()
889 		return -EINVAL;  in twl6030_gpadc_probe()
893 		return -ENOMEM;  in twl6030_gpadc_probe()
897 	gpadc->twl6030_cal_tbl = devm_kcalloc(dev,  in twl6030_gpadc_probe()
898 					pdata->nchannels,  in twl6030_gpadc_probe()
899 					sizeof(*gpadc->twl6030_cal_tbl),  in twl6030_gpadc_probe()
901 	if (!gpadc->twl6030_cal_tbl)  in twl6030_gpadc_probe()
902 		return -ENOMEM;  in twl6030_gpadc_probe()
904 	gpadc->dev = dev;  in twl6030_gpadc_probe()
905 	gpadc->pdata = pdata;  in twl6030_gpadc_probe()
908 	mutex_init(&gpadc->lock);  in twl6030_gpadc_probe()
909 	init_completion(&gpadc->irq_complete);  in twl6030_gpadc_probe()
911 	ret = pdata->calibrate(gpadc);  in twl6030_gpadc_probe()
960 	indio_dev->name = DRIVER_NAME;  in twl6030_gpadc_probe()
961 	indio_dev->info = &twl6030_gpadc_iio_info;  in twl6030_gpadc_probe()
962 	indio_dev->modes = INDIO_DIRECT_MODE;  in twl6030_gpadc_probe()
963 	indio_dev->channels = pdata->iio_channels;  in twl6030_gpadc_probe()
964 	indio_dev->num_channels = pdata->nchannels;  in twl6030_gpadc_probe()