iio/adc/ad7298.c

106 	struct ad7298_state *st = iio_priv(indio_dev);
114 	command = AD7298_WRITE | st->ext_ref;
120 	st->tx_buf[0] = cpu_to_be16(command);
123 	st->ring_xfer[0].tx_buf = &st->tx_buf[0];
124 	st->ring_xfer[0].len = 2;
125 	st->ring_xfer[0].cs_change = 1;
126 	st->ring_xfer[1].tx_buf = &st->tx_buf[1];
127 	st->ring_xfer[1].len = 2;
128 	st->ring_xfer[1].cs_change = 1;
130 	spi_message_init(&st->ring_msg);
131 	spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg);
132 	spi_message_add_tail(&st->ring_xfer[1], &st->ring_msg);
135 		st->ring_xfer[i + 2].rx_buf = &st->rx_buf[i];
136 		st->ring_xfer[i + 2].len = 2;
137 		st->ring_xfer[i + 2].cs_change = 1;
138 		spi_message_add_tail(&st->ring_xfer[i + 2], &st->ring_msg);
141 	st->ring_xfer[i + 1].cs_change = 0;
150 	struct ad7298_state *st = iio_priv(indio_dev);
153 	b_sent = spi_sync(st->spi, &st->ring_msg);
157 	iio_push_to_buffers_with_timestamp(indio_dev, st->rx_buf,
166 static int ad7298_scan_direct(struct ad7298_state *st, unsigned ch)
169 	st->tx_buf[0] = cpu_to_be16(AD7298_WRITE | st->ext_ref |
172 	ret = spi_sync(st->spi, &st->scan_single_msg);
176 	return be16_to_cpu(st->rx_buf[0]);
179 static int ad7298_scan_temp(struct ad7298_state *st, int *val)
185 			  AD7298_TAVG | st->ext_ref);
187 	ret = spi_write(st->spi, (u8 *)&buf, 2);
193 	ret = spi_write(st->spi, (u8 *)&buf, 2);
199 	ret = spi_read(st->spi, (u8 *)&buf, 2);
208 static int ad7298_get_ref_voltage(struct ad7298_state *st)
212 	if (st->reg) {
213 		vref = regulator_get_voltage(st->reg);
230 	struct ad7298_state *st = iio_priv(indio_dev);
239 			ret = ad7298_scan_temp(st, val);
241 			ret = ad7298_scan_direct(st, chan->address);
255 			*val = ad7298_get_ref_voltage(st);
259 			*val = ad7298_get_ref_voltage(st);
266 		*val = 1093 - 2732500 / ad7298_get_ref_voltage(st);
286 	struct ad7298_state *st;
290 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
294 	st = iio_priv(indio_dev);
296 	st->reg = devm_regulator_get_optional(&spi->dev, "vref");
297 	if (!IS_ERR(st->reg)) {
298 		st->ext_ref = AD7298_EXTREF;
300 		ret = PTR_ERR(st->reg);
304 		st->reg = NULL;
307 	if (st->reg) {
308 		ret = regulator_enable(st->reg);
313 					       st->reg);
318 	st->spi = spi;
328 	st->scan_single_xfer[0].tx_buf = &st->tx_buf[0];
329 	st->scan_single_xfer[0].len = 2;
330 	st->scan_single_xfer[0].cs_change = 1;
331 	st->scan_single_xfer[1].tx_buf = &st->tx_buf[1];
332 	st->scan_single_xfer[1].len = 2;
333 	st->scan_single_xfer[1].cs_change = 1;
334 	st->scan_single_xfer[2].rx_buf = &st->rx_buf[0];
335 	st->scan_single_xfer[2].len = 2;
337 	spi_message_init(&st->scan_single_msg);
338 	spi_message_add_tail(&st->scan_single_xfer[0], &st->scan_single_msg);
339 	spi_message_add_tail(&st->scan_single_xfer[1], &st->scan_single_msg);
340 	spi_message_add_tail(&st->scan_single_xfer[2], &st->scan_single_msg);