1 // SPDX-License-Identifier: GPL-2.0-only
3  * MAX1117/MAX1118/MAX1119 8-bit, dual-channel ADCs driver
7  * Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX1117-MAX1119.pdf
13  * ------  ---------  -----------
14  * nCS        -->     CNVST
15  * SCK        -->     SCLK
16  * MISO       <--     DOUT
17  * ------  ---------  -----------
76 		 * and low for a second time.  in max1118_read()
80 			.delay = {	/* > CNVST Low Time 100 ns */  in max1118_read()
87 		 * The acquisition interval begins with the falling edge of  in max1118_read()
88 		 * CNVST.  The total acquisition and conversion process takes  in max1118_read()
99 			.rx_buf = &adc->data,  in max1118_read()
113 	return adc->data;  in max1118_read()
123 	switch (id->driver_data) {  in max1118_get_vref_mV()
129 		vref_uV = regulator_get_voltage(adc->reg);  in max1118_get_vref_mV()
135 	return -ENODEV;  in max1118_get_vref_mV()
146 		mutex_lock(&adc->lock);  in max1118_read_raw()
147 		*val = max1118_read(adc->spi, chan->channel);  in max1118_read_raw()
148 		mutex_unlock(&adc->lock);  in max1118_read_raw()
154 		*val = max1118_get_vref_mV(adc->spi);  in max1118_read_raw()
162 	return -EINVAL;  in max1118_read_raw()
172 	struct iio_dev *indio_dev = pf->indio_dev;  in max1118_trigger_handler()
177 	mutex_lock(&adc->lock);  in max1118_trigger_handler()
179 	for_each_set_bit(scan_index, indio_dev->active_scan_mask,  in max1118_trigger_handler()
180 			indio_dev->masklength) {  in max1118_trigger_handler()
182 				&indio_dev->channels[scan_index];  in max1118_trigger_handler()
183 		int ret = max1118_read(adc->spi, scan_chan->channel);  in max1118_trigger_handler()
186 			dev_warn(&adc->spi->dev,  in max1118_trigger_handler()
191 		adc->scan.channels[i] = ret;  in max1118_trigger_handler()
194 	iio_push_to_buffers_with_timestamp(indio_dev, &adc->scan,  in max1118_trigger_handler()
197 	mutex_unlock(&adc->lock);  in max1118_trigger_handler()
199 	iio_trigger_notify_done(indio_dev->trig);  in max1118_trigger_handler()
211 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc));  in max1118_probe()
213 		return -ENOMEM;  in max1118_probe()
216 	adc->spi = spi;  in max1118_probe()
217 	mutex_init(&adc->lock);  in max1118_probe()
219 	if (id->driver_data == max1118) {  in max1118_probe()
220 		adc->reg = devm_regulator_get(&spi->dev, "vref");  in max1118_probe()
221 		if (IS_ERR(adc->reg)) {  in max1118_probe()
222 			dev_err(&spi->dev, "failed to get vref regulator\n");  in max1118_probe()
223 			return PTR_ERR(adc->reg);  in max1118_probe()
225 		ret = regulator_enable(adc->reg);  in max1118_probe()
232 	indio_dev->name = spi_get_device_id(spi)->name;  in max1118_probe()
233 	indio_dev->info = &max1118_info;  in max1118_probe()
234 	indio_dev->modes = INDIO_DIRECT_MODE;  in max1118_probe()
235 	indio_dev->channels = max1118_channels;  in max1118_probe()
236 	indio_dev->num_channels = ARRAY_SIZE(max1118_channels);  in max1118_probe()
260 	if (id->driver_data == max1118)  in max1118_probe()
261 		regulator_disable(adc->reg);  in max1118_probe()
274 	if (id->driver_data == max1118)  in max1118_remove()
275 		return regulator_disable(adc->reg);  in max1118_remove()