iio/adc/mcp320x.c

120 static int mcp320x_adc_conversion(struct mcp320x *adc, u8 channel,
125 	if (adc->chip_info->conv_time) {
126 		ret = spi_sync(adc->spi, &adc->start_conv_msg);
130 		usleep_range(adc->chip_info->conv_time,
131 			     adc->chip_info->conv_time + 100);
134 	memset(&adc->rx_buf, 0, sizeof(adc->rx_buf));
135 	if (adc->chip_info->num_channels > 1)
136 		adc->tx_buf = mcp320x_channel_to_tx_data(device_index, channel,
139 	ret = spi_sync(adc->spi, &adc->msg);
145 		*val = (adc->rx_buf[0] << 5 | adc->rx_buf[1] >> 3);
150 		*val = (adc->rx_buf[0] << 2 | adc->rx_buf[1] >> 6);
153 		*val = (adc->rx_buf[0] << 7 | adc->rx_buf[1] >> 1);
158 		*val = (adc->rx_buf[0] << 4 | adc->rx_buf[1] >> 4);
161 		*val = sign_extend32((adc->rx_buf[0] & 0x1f) << 8
162 				    | adc->rx_buf[1], 12);
168 		u32 raw = be32_to_cpup((__be32 *)adc->rx_buf);
170 		if (!(adc->spi->mode & SPI_CPOL))
198 	struct mcp320x *adc = iio_priv(indio_dev);
202 	mutex_lock(&adc->lock);
204 	device_index = spi_get_device_id(adc->spi)->driver_data;
208 		ret = mcp320x_adc_conversion(adc, channel->address,
217 		ret = regulator_get_voltage(adc->reg);
223 		*val2 = adc->chip_info->resolution;
229 	mutex_unlock(&adc->lock);
382 	struct mcp320x *adc;
386 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc));
390 	adc = iio_priv(indio_dev);
391 	adc->spi = spi;
402 	adc->chip_info = chip_info;
404 	adc->transfer[0].tx_buf = &adc->tx_buf;
405 	adc->transfer[0].len = sizeof(adc->tx_buf);
406 	adc->transfer[1].rx_buf = adc->rx_buf;
407 	adc->transfer[1].len = DIV_ROUND_UP(chip_info->resolution, 8);
411 		spi_message_init_with_transfers(&adc->msg,
412 						&adc->transfer[1], 1);
414 		spi_message_init_with_transfers(&adc->msg, adc->transfer,
415 						ARRAY_SIZE(adc->transfer));
424 			adc->transfer[1].len++;
427 		adc->start_conv_transfer.delay.value = 8;
428 		adc->start_conv_transfer.delay.unit = SPI_DELAY_UNIT_USECS;
429 		spi_message_init_with_transfers(&adc->start_conv_msg,
430 						&adc->start_conv_transfer, 1);
440 		mcp320x_adc_conversion(adc, 0, 1, device_index, &ret);
441 		mcp320x_adc_conversion(adc, 0, 1, device_index, &ret);
444 	adc->reg = devm_regulator_get(&spi->dev, "vref");
445 	if (IS_ERR(adc->reg))
446 		return PTR_ERR(adc->reg);
448 	ret = regulator_enable(adc->reg);
452 	ret = devm_add_action_or_reset(&spi->dev, mcp320x_regulator_disable, adc->reg);
456 	mutex_init(&adc->lock);