1 // SPDX-License-Identifier: GPL-2.0+
34 #define AD4000_CFG_HIGHZ		BIT(2) /* High impedance mode  */
56 		.shift = _storage_bits - _real_bits,				\
78 		.shift = _storage_bits - _real_bits,				\
98 /* maps adi,sdi-pin property value to enum */
101 	[AD4000_SDI_VIO] = "high",
254 	if (chan->scan_type.sign == 's')  in ad4000_fill_scale_tbl()
255 		scale_bits = chan->scan_type.realbits - 1;  in ad4000_fill_scale_tbl()
257 		scale_bits = chan->scan_type.realbits;  in ad4000_fill_scale_tbl()
265 	val = mult_frac(st->vref_mv, MICRO, st->gain_milli);  in ad4000_fill_scale_tbl()
272 	st->scale_tbl[0][0] = tmp0; /* Integer part */  in ad4000_fill_scale_tbl()
273 	st->scale_tbl[0][1] = abs(tmp1); /* Fractional part */  in ad4000_fill_scale_tbl()
276 	st->scale_tbl[1][0] = tmp0;  in ad4000_fill_scale_tbl()
279 	if (chan->differential)  in ad4000_fill_scale_tbl()
280 		st->scale_tbl[1][1] = DIV_ROUND_CLOSEST(abs(tmp1) * 4, 5);  in ad4000_fill_scale_tbl()
282 		st->scale_tbl[1][1] = DIV_ROUND_CLOSEST(abs(tmp1) * 9, 10);  in ad4000_fill_scale_tbl()
287 	st->tx_buf[0] = AD4000_WRITE_COMMAND;  in ad4000_write_reg()
288 	st->tx_buf[1] = val;  in ad4000_write_reg()
289 	return spi_write(st->spi, st->tx_buf, ARRAY_SIZE(st->tx_buf));  in ad4000_write_reg()
295 		.tx_buf = st->tx_buf,  in ad4000_read_reg()
296 		.rx_buf = st->rx_buf,  in ad4000_read_reg()
301 	st->tx_buf[0] = AD4000_READ_COMMAND;  in ad4000_read_reg()
302 	ret = spi_sync_transfer(st->spi, &t, 1);  in ad4000_read_reg()
306 	*val = st->rx_buf[1];  in ad4000_read_reg()
315 	 * In 4-wire mode, the CNV line is held high for the entire conversion  in ad4000_convert_and_acquire()
318 	 * gpiod_set_value_cansleep() has no effect.  in ad4000_convert_and_acquire()
320 	gpiod_set_value_cansleep(st->cnv_gpio, 1);  in ad4000_convert_and_acquire()
321 	ret = spi_sync(st->spi, &st->msg);  in ad4000_convert_and_acquire()
322 	gpiod_set_value_cansleep(st->cnv_gpio, 0);  in ad4000_convert_and_acquire()
338 	if (chan->scan_type.storagebits > 16)  in ad4000_single_conversion()
339 		sample = be32_to_cpu(st->scan.data.sample_buf32);  in ad4000_single_conversion()
341 		sample = be16_to_cpu(st->scan.data.sample_buf16);  in ad4000_single_conversion()
343 	sample >>= chan->scan_type.shift;  in ad4000_single_conversion()
345 	if (chan->scan_type.sign == 's')  in ad4000_single_conversion()
346 		*val = sign_extend32(sample, chan->scan_type.realbits - 1);  in ad4000_single_conversion()
359 		iio_device_claim_direct_scoped(return -EBUSY, indio_dev)  in ad4000_read_raw()
363 		*val = st->scale_tbl[st->span_comp][0];  in ad4000_read_raw()
364 		*val2 = st->scale_tbl[st->span_comp][1];  in ad4000_read_raw()
368 		if (st->span_comp)  in ad4000_read_raw()
369 			*val = mult_frac(st->vref_mv, 1, 10);  in ad4000_read_raw()
373 		return -EINVAL;  in ad4000_read_raw()
386 		*vals = (int *)st->scale_tbl;  in ad4000_read_avail()
391 		return -EINVAL;  in ad4000_read_avail()
417 		iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {  in ad4000_write_raw()
418 			guard(mutex)(&st->lock);  in ad4000_write_raw()
424 			span_comp_en = val2 == st->scale_tbl[1][1];  in ad4000_write_raw()
432 			st->span_comp = span_comp_en;  in ad4000_write_raw()
437 		return -EINVAL;  in ad4000_write_raw()
444 	struct iio_dev *indio_dev = pf->indio_dev;  in ad4000_trigger_handler()
452 	iio_push_to_buffers_with_timestamp(indio_dev, &st->scan, pf->timestamp);  in ad4000_trigger_handler()
455 	iio_trigger_notify_done(indio_dev->trig);  in ad4000_trigger_handler()
472  * in "3-wire" mode, selected when the adi,sdi-pin device tree property is
473  * absent or set to "high". In this connection mode, the ADC SDI pin is
490 	struct spi_transfer *xfers = st->xfers;  in ad4000_prepare_3wire_mode_message()
496 	xfers[1].rx_buf = &st->scan.data;  in ad4000_prepare_3wire_mode_message()
497 	xfers[1].len = BITS_TO_BYTES(chan->scan_type.storagebits);  in ad4000_prepare_3wire_mode_message()
501 	spi_message_init_with_transfers(&st->msg, st->xfers, 2);  in ad4000_prepare_3wire_mode_message()
503 	return devm_spi_optimize_message(&st->spi->dev, st->spi, &st->msg);  in ad4000_prepare_3wire_mode_message()
508  * in "4-wire" mode, selected when the adi,sdi-pin device tree property is
517 	struct spi_transfer *xfers = st->xfers;  in ad4000_prepare_4wire_mode_message()
520 	 * Dummy transfer to cause enough delay between CNV going high and SDI  in ad4000_prepare_4wire_mode_message()
527 	xfers[1].rx_buf = &st->scan.data;  in ad4000_prepare_4wire_mode_message()
528 	xfers[1].len = BITS_TO_BYTES(chan->scan_type.storagebits);  in ad4000_prepare_4wire_mode_message()
530 	spi_message_init_with_transfers(&st->msg, st->xfers, 2);  in ad4000_prepare_4wire_mode_message()
532 	return devm_spi_optimize_message(&st->spi->dev, st->spi, &st->msg);  in ad4000_prepare_4wire_mode_message()
539 	if (device_property_present(&st->spi->dev, "adi,high-z-input"))  in ad4000_config()
548 	struct device *dev = &spi->dev;  in ad4000_probe()
555 		return -ENOMEM;  in ad4000_probe()
559 		return -EINVAL;  in ad4000_probe()
562 	st->spi = spi;  in ad4000_probe()
569 	ret = devm_regulator_get_enable_read_voltage(dev, "ref");  in ad4000_probe()
572 				     "Failed to get ref regulator reference\n");  in ad4000_probe()
573 	st->vref_mv = ret / 1000;  in ad4000_probe()
575 	st->cnv_gpio = devm_gpiod_get_optional(dev, "cnv", GPIOD_OUT_HIGH);  in ad4000_probe()
576 	if (IS_ERR(st->cnv_gpio))  in ad4000_probe()
577 		return dev_err_probe(dev, PTR_ERR(st->cnv_gpio),  in ad4000_probe()
580 	ret = device_property_match_property_string(dev, "adi,sdi-pin",  in ad4000_probe()
583 	if (ret < 0 && ret != -EINVAL)  in ad4000_probe()
585 				     "getting adi,sdi-pin property failed\n");  in ad4000_probe()
588 	st->sdi_pin = ret == -EINVAL ? AD4000_SDI_MOSI : ret;  in ad4000_probe()
589 	switch (st->sdi_pin) {  in ad4000_probe()
591 		indio_dev->info = &ad4000_reg_access_info;  in ad4000_probe()
592 		indio_dev->channels = &chip->reg_access_chan_spec;  in ad4000_probe()
595 		 * In "3-wire mode", the ADC SDI line must be kept high when  in ad4000_probe()
597 		 * Request the SPI controller to make MOSI idle high.  in ad4000_probe()
599 		spi->mode |= SPI_MOSI_IDLE_HIGH;  in ad4000_probe()
604 		ret = ad4000_prepare_3wire_mode_message(st, indio_dev->channels);  in ad4000_probe()
614 		indio_dev->info = &ad4000_info;  in ad4000_probe()
615 		indio_dev->channels = &chip->chan_spec;  in ad4000_probe()
616 		ret = ad4000_prepare_3wire_mode_message(st, indio_dev->channels);  in ad4000_probe()
622 		indio_dev->info = &ad4000_info;  in ad4000_probe()
623 		indio_dev->channels = &chip->chan_spec;  in ad4000_probe()
624 		ret = ad4000_prepare_4wire_mode_message(st, indio_dev->channels);  in ad4000_probe()
630 		return dev_err_probe(dev, -EPROTONOSUPPORT,  in ad4000_probe()
634 		return dev_err_probe(dev, -EINVAL, "Unrecognized connection mode\n");  in ad4000_probe()
637 	indio_dev->name = chip->dev_name;  in ad4000_probe()
638 	indio_dev->num_channels = 1;  in ad4000_probe()
640 	devm_mutex_init(dev, &st->lock);  in ad4000_probe()
642 	st->gain_milli = 1000;  in ad4000_probe()
643 	if (chip->has_hardware_gain) {  in ad4000_probe()
644 		ret = device_property_read_u16(dev, "adi,gain-milli",  in ad4000_probe()
645 					       &st->gain_milli);  in ad4000_probe()
648 			gain_idx = find_closest(st->gain_milli, ad4000_gains,  in ad4000_probe()
650 			st->gain_milli = ad4000_gains[gain_idx];  in ad4000_probe()
657 	ad4000_fill_scale_tbl(st, indio_dev->channels);  in ad4000_probe()