4  * Copyright (c) 2013-2015 Intel Corporation.
36  * In case of ACPI, we use the hard-wired 5000 mV of the Galileo and IOT2000
38  * via the vref-supply regulator.
45  * chips. The ADC108S102 effectively returns a 12-bit result with the 2
46  * least-significant bits unset.
52  * 16-bit SPI command format:
54  *   [13:11] 3-bit channel address
60  * 16-bit SPI response format:
62  *   [11:0]  12-bit ADC sample (for ADC108S102, [1:0] will always be 0).
85 	 *  rx_buf: 1 dummy response, 8 channel responses, plus 64-bit timestamp
132 		st->tx_buf[cmds++] = cpu_to_be16(ADC108S102_CMD(bit));  in adc108s102_update_scan_mode()
135 	st->tx_buf[cmds++] = 0x00;  in adc108s102_update_scan_mode()
138 	st->ring_xfer.tx_buf = &st->tx_buf[0];  in adc108s102_update_scan_mode()
139 	st->ring_xfer.rx_buf = &st->rx_buf[0];  in adc108s102_update_scan_mode()
140 	st->ring_xfer.len = cmds * sizeof(st->tx_buf[0]);  in adc108s102_update_scan_mode()
142 	spi_message_init_with_transfers(&st->ring_msg, &st->ring_xfer, 1);  in adc108s102_update_scan_mode()
147 static irqreturn_t adc108s102_trigger_handler(int irq, void *p)  in adc108s102_trigger_handler()  argument
149 	struct iio_poll_func *pf = p;  in adc108s102_trigger_handler()
150 	struct iio_dev *indio_dev = pf->indio_dev;  in adc108s102_trigger_handler()
154 	ret = spi_sync(st->spi, &st->ring_msg);  in adc108s102_trigger_handler()
160 					   (u8 *)&st->rx_buf[1],  in adc108s102_trigger_handler()
164 	iio_trigger_notify_done(indio_dev->trig);  in adc108s102_trigger_handler()
173 	st->tx_buf[0] = cpu_to_be16(ADC108S102_CMD(ch));  in adc108s102_scan_direct()
174 	ret = spi_sync(st->spi, &st->scan_single_msg);  in adc108s102_scan_direct()
179 	return be16_to_cpu(st->rx_buf[1]);  in adc108s102_scan_direct()
195 		ret = adc108s102_scan_direct(st, chan->address);  in adc108s102_read_raw()
206 		if (chan->type != IIO_VOLTAGE)  in adc108s102_read_raw()
209 		*val = st->va_millivolt;  in adc108s102_read_raw()
210 		*val2 = chan->scan_type.realbits;  in adc108s102_read_raw()
217 	return -EINVAL;  in adc108s102_read_raw()
231 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));  in adc108s102_probe()
233 		return -ENOMEM;  in adc108s102_probe()
237 	if (ACPI_COMPANION(&spi->dev)) {  in adc108s102_probe()
238 		st->va_millivolt = ADC108S102_VA_MV_ACPI_DEFAULT;  in adc108s102_probe()
240 		st->reg = devm_regulator_get(&spi->dev, "vref");  in adc108s102_probe()
241 		if (IS_ERR(st->reg))  in adc108s102_probe()
242 			return PTR_ERR(st->reg);  in adc108s102_probe()
244 		ret = regulator_enable(st->reg);  in adc108s102_probe()
246 			dev_err(&spi->dev, "Cannot enable vref regulator\n");  in adc108s102_probe()
250 		ret = regulator_get_voltage(st->reg);  in adc108s102_probe()
252 			dev_err(&spi->dev, "vref get voltage failed\n");  in adc108s102_probe()
256 		st->va_millivolt = ret / 1000;  in adc108s102_probe()
260 	st->spi = spi;  in adc108s102_probe()
262 	indio_dev->name = spi->modalias;  in adc108s102_probe()
263 	indio_dev->dev.parent = &spi->dev;  in adc108s102_probe()
264 	indio_dev->modes = INDIO_DIRECT_MODE;  in adc108s102_probe()
265 	indio_dev->channels = adc108s102_channels;  in adc108s102_probe()
266 	indio_dev->num_channels = ARRAY_SIZE(adc108s102_channels);  in adc108s102_probe()
267 	indio_dev->info = &adc108s102_info;  in adc108s102_probe()
270 	st->scan_single_xfer.tx_buf = st->tx_buf;  in adc108s102_probe()
271 	st->scan_single_xfer.rx_buf = st->rx_buf;  in adc108s102_probe()
272 	st->scan_single_xfer.len = 2 * sizeof(st->tx_buf[0]);  in adc108s102_probe()
274 	spi_message_init_with_transfers(&st->scan_single_msg,  in adc108s102_probe()
275 					&st->scan_single_xfer, 1);  in adc108s102_probe()
284 		dev_err(&spi->dev, "Failed to register IIO device\n");  in adc108s102_probe()
293 	regulator_disable(st->reg);  in adc108s102_probe()
306 	regulator_disable(st->reg);  in adc108s102_remove()