1 // SPDX-License-Identifier: GPL-2.0
33 		*val *= rescale->numerator;  in rescale_process_scale()
34 		if (rescale->denominator == 1)  in rescale_process_scale()
36 		*val2 = rescale->denominator;  in rescale_process_scale()
44 		if (!check_mul_overflow(*val, rescale->numerator, &_val) &&  in rescale_process_scale()
45 		    !check_mul_overflow(*val2, rescale->denominator, &_val2)) {  in rescale_process_scale()
53 		tmp = div_s64(tmp, rescale->denominator);  in rescale_process_scale()
54 		tmp *= rescale->numerator;  in rescale_process_scale()
82 		 * *val = 1 and *val2 = -0.5 yields -1.5 not -0.5.  in rescale_process_scale()
86 		tmp = (s64)abs(*val) * abs(rescale->numerator);  in rescale_process_scale()
87 		*val = div_s64_rem(tmp, abs(rescale->denominator), &rem);  in rescale_process_scale()
89 		tmp = (s64)rem * mult + (s64)abs(*val2) * abs(rescale->numerator);  in rescale_process_scale()
90 		tmp = div_s64(tmp, abs(rescale->denominator));  in rescale_process_scale()
98 		if (neg ^ ((rescale->numerator < 0) ^ (rescale->denominator < 0))) {  in rescale_process_scale()
100 				*val = -*val;  in rescale_process_scale()
102 				*val2 = -*val2;  in rescale_process_scale()
107 		return -EOPNOTSUPP;  in rescale_process_scale()
120 		tmp = (s64)rescale->offset * scale2;  in rescale_process_offset()
124 		*val = div_s64(rescale->offset, scale) + schan_off;  in rescale_process_offset()
127 		tmp = (s64)rescale->offset * (1 << scale2);  in rescale_process_offset()
131 		tmp = (s64)rescale->offset * 1000000000LL;  in rescale_process_offset()
136 		tmp = (s64)rescale->offset * 1000000LL;  in rescale_process_offset()
141 		return -EOPNOTSUPP;  in rescale_process_offset()
157 		if (rescale->chan_processed)  in rescale_read_raw()
163 			return iio_read_channel_processed(rescale->source, val);  in rescale_read_raw()
165 			return iio_read_channel_raw(rescale->source, val);  in rescale_read_raw()
168 		if (rescale->chan_processed) {  in rescale_read_raw()
170 			 * Processed channels are scaled 1-to-1  in rescale_read_raw()
176 			ret = iio_read_channel_scale(rescale->source, val, val2);  in rescale_read_raw()
181 		 * Processed channels are scaled 1-to-1 and source offset is  in rescale_read_raw()
202 		 *	offset = schan_offset + rescaler_offset / schan_scale  in rescale_read_raw()
204 		if (rescale->chan_processed) {  in rescale_read_raw()
205 			*val = rescale->offset;  in rescale_read_raw()
209 		if (iio_channel_has_info(rescale->source->channel,  in rescale_read_raw()
211 			ret = iio_read_channel_offset(rescale->source,  in rescale_read_raw()
214 				return ret < 0 ? ret : -EOPNOTSUPP;  in rescale_read_raw()
217 		if (iio_channel_has_info(rescale->source->channel,  in rescale_read_raw()
219 			ret = iio_read_channel_scale(rescale->source, &scale, &scale2);  in rescale_read_raw()
226 		 * rescaler and offset, if any.  in rescale_read_raw()
231 		return -EINVAL;  in rescale_read_raw()
245 		return iio_read_avail_channel_raw(rescale->source,  in rescale_read_avail()
248 		return -EINVAL;  in rescale_read_avail()
264 	return iio_read_channel_ext_info(rescale->source,  in rescale_read_ext_info()
265 					 rescale->ext_info[private].name,  in rescale_read_ext_info()
276 	return iio_write_channel_ext_info(rescale->source,  in rescale_write_ext_info()
277 					  rescale->ext_info[private].name,  in rescale_write_ext_info()
284 	struct iio_chan_spec *chan = &rescale->chan;  in rescale_configure_channel()
285 	struct iio_chan_spec const *schan = rescale->source->channel;  in rescale_configure_channel()
287 	chan->indexed = 1;  in rescale_configure_channel()
288 	chan->output = schan->output;  in rescale_configure_channel()
289 	chan->ext_info = rescale->ext_info;  in rescale_configure_channel()
290 	chan->type = rescale->cfg->type;  in rescale_configure_channel()
295 		dev_info(dev, "using raw+scale/offset source channel\n");  in rescale_configure_channel()
298 		rescale->chan_processed = true;  in rescale_configure_channel()
301 		return -EINVAL;  in rescale_configure_channel()
304 	chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  in rescale_configure_channel()
307 	if (rescale->offset)  in rescale_configure_channel()
308 		chan->info_mask_separate |= BIT(IIO_CHAN_INFO_OFFSET);  in rescale_configure_channel()
316 	    !rescale->chan_processed)  in rescale_configure_channel()
317 		chan->info_mask_separate_available |= BIT(IIO_CHAN_INFO_RAW);  in rescale_configure_channel()
331 	ret = device_property_read_u32(dev, "sense-resistor-micro-ohms",  in rescale_current_sense_amplifier_props()
338 	device_property_read_u32(dev, "sense-gain-mult", &gain_mult);  in rescale_current_sense_amplifier_props()
339 	device_property_read_u32(dev, "sense-gain-div", &gain_div);  in rescale_current_sense_amplifier_props()
347 	rescale->numerator = 1000000 / factor;  in rescale_current_sense_amplifier_props()
348 	rescale->denominator = sense / factor;  in rescale_current_sense_amplifier_props()
350 	factor = gcd(rescale->numerator, gain_mult);  in rescale_current_sense_amplifier_props()
351 	rescale->numerator /= factor;  in rescale_current_sense_amplifier_props()
352 	rescale->denominator *= gain_mult / factor;  in rescale_current_sense_amplifier_props()
354 	factor = gcd(rescale->denominator, gain_div);  in rescale_current_sense_amplifier_props()
355 	rescale->numerator *= gain_div / factor;  in rescale_current_sense_amplifier_props()
356 	rescale->denominator /= factor;  in rescale_current_sense_amplifier_props()
368 	ret = device_property_read_u32(dev, "shunt-resistor-micro-ohms",  in rescale_current_sense_shunt_props()
376 	rescale->numerator = 1000000 / factor;  in rescale_current_sense_shunt_props()
377 	rescale->denominator = shunt / factor;  in rescale_current_sense_shunt_props()
388 	ret = device_property_read_u32(dev, "output-ohms",  in rescale_voltage_divider_props()
389 				       &rescale->denominator);  in rescale_voltage_divider_props()
391 		dev_err(dev, "failed to read output-ohms: %d\n", ret);  in rescale_voltage_divider_props()
395 	ret = device_property_read_u32(dev, "full-ohms",  in rescale_voltage_divider_props()
396 				       &rescale->numerator);  in rescale_voltage_divider_props()
398 		dev_err(dev, "failed to read full-ohms: %d\n", ret);  in rescale_voltage_divider_props()
402 	factor = gcd(rescale->numerator, rescale->denominator);  in rescale_voltage_divider_props()
403 	rescale->numerator /= factor;  in rescale_voltage_divider_props()
404 	rescale->denominator /= factor;  in rescale_voltage_divider_props()
419 	ret = device_property_read_u32(dev, "excitation-current-microamp",  in rescale_temp_sense_rtd_props()
422 		dev_err(dev, "failed to read excitation-current-microamp: %d\n",  in rescale_temp_sense_rtd_props()
427 	ret = device_property_read_u32(dev, "alpha-ppm-per-celsius", &alpha);  in rescale_temp_sense_rtd_props()
429 		dev_err(dev, "failed to read alpha-ppm-per-celsius: %d\n",  in rescale_temp_sense_rtd_props()
434 	ret = device_property_read_u32(dev, "r-naught-ohms", &r0);  in rescale_temp_sense_rtd_props()
436 		dev_err(dev, "failed to read r-naught-ohms: %d\n", ret);  in rescale_temp_sense_rtd_props()
442 	rescale->numerator = 1000000 / factor;  in rescale_temp_sense_rtd_props()
443 	rescale->denominator = tmp / factor;  in rescale_temp_sense_rtd_props()
445 	rescale->offset = -1 * ((r0 * iexc) / 1000);  in rescale_temp_sense_rtd_props()
453 	s32 offset = 0;  in rescale_temp_transducer_props()  local
458 	device_property_read_u32(dev, "sense-offset-millicelsius", &offset);  in rescale_temp_transducer_props()
459 	device_property_read_u32(dev, "sense-resistor-ohms", &sense);  in rescale_temp_transducer_props()
460 	ret = device_property_read_u32(dev, "alpha-ppm-per-celsius", &alpha);  in rescale_temp_transducer_props()
462 		dev_err(dev, "failed to read alpha-ppm-per-celsius: %d\n", ret);  in rescale_temp_transducer_props()
466 	rescale->numerator = 1000000;  in rescale_temp_transducer_props()
467 	rescale->denominator = alpha * sense;  in rescale_temp_transducer_props()
469 	rescale->offset = div_s64((s64)offset * rescale->denominator,  in rescale_temp_transducer_props()
470 				  rescale->numerator);  in rescale_temp_transducer_props()
507 	{ .compatible = "current-sense-amplifier",
509 	{ .compatible = "current-sense-shunt",
511 	{ .compatible = "voltage-divider",
513 	{ .compatible = "temperature-sense-rtd",
515 	{ .compatible = "temperature-transducer",
523 	struct device *dev = &pdev->dev;  in rescale_probe()
540 		sizeof_ext_info *= sizeof(*rescale->ext_info);  in rescale_probe()
547 		return -ENOMEM;  in rescale_probe()
551 	rescale->cfg = device_get_match_data(dev);  in rescale_probe()
552 	rescale->numerator = 1;  in rescale_probe()
553 	rescale->denominator = 1;  in rescale_probe()
554 	rescale->offset = 0;  in rescale_probe()
556 	ret = rescale->cfg->props(dev, rescale);  in rescale_probe()
560 	if (!rescale->numerator || !rescale->denominator) {  in rescale_probe()
562 		return -EINVAL;  in rescale_probe()
567 	rescale->source = source;  in rescale_probe()
569 	indio_dev->name = dev_name(dev);  in rescale_probe()
570 	indio_dev->info = &rescale_info;  in rescale_probe()
571 	indio_dev->modes = INDIO_DIRECT_MODE;  in rescale_probe()
572 	indio_dev->channels = &rescale->chan;  in rescale_probe()
573 	indio_dev->num_channels = 1;  in rescale_probe()
575 		rescale->ext_info = devm_kmemdup(dev,  in rescale_probe()
576 						 source->channel->ext_info,  in rescale_probe()
578 		if (!rescale->ext_info)  in rescale_probe()
579 			return -ENOMEM;  in rescale_probe()
581 		for (i = 0; rescale->ext_info[i].name; ++i) {  in rescale_probe()
583 				&rescale->ext_info[i];  in rescale_probe()
585 			if (source->channel->ext_info[i].read)  in rescale_probe()
586 				ext_info->read = rescale_read_ext_info;  in rescale_probe()
587 			if (source->channel->ext_info[i].write)  in rescale_probe()
588 				ext_info->write = rescale_write_ext_info;  in rescale_probe()
589 			ext_info->private = i;  in rescale_probe()
603 		.name = "iio-rescale",