v3: Functions moved around. Return values is simpler. Signed-off-by: Soeren Andersen <san at rosetechnology.dk> --- drivers/iio/adc/mcp320x.c | 201 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-------------------------- 1 file changed, 172 insertions(+), 29 deletions(-) diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c index 28a086e..77ee363 100644 --- a/drivers/iio/adc/mcp320x.c +++ b/drivers/iio/adc/mcp320x.c @@ -1,9 +1,20 @@ /* * Copyright (C) 2013 Oskar Andero <oskar.andero@xxxxxxxxx> + * Copyright (C) 2014 Allan Bendorff Jensen <abj@xxxxxxxxxxxxxxxxx> * - * Driver for Microchip Technology's MCP3204 and MCP3208 ADC chips. - * Datasheet can be found here: - * http://ww1.microchip.com/downloads/en/devicedoc/21298c.pdf + * Driver for following ADC chips from Microchip Technology's: + * 10 Bit converter + * MCP3001 + * MCP3002 + * MCP3004 + * MCP3008 + * ------------ + * 12 bit converter + * MCP3201 + * MCP3202 + * MCP3204 + * MCP3208 + * ------------ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -16,10 +27,16 @@ #include <linux/iio/iio.h> #include <linux/regulator/consumer.h> -#define MCP_SINGLE_ENDED (1 << 3) -#define MCP_START_BIT (1 << 4) +static int mcp320x_channel_to_tx_data(int device_index, + const unsigned int channel, bool differential); enum { + mcp3001, + mcp3002, + mcp3004, + mcp3008, + mcp3201, + mcp3202, mcp3204, mcp3208, }; @@ -36,17 +53,48 @@ struct mcp320x { struct mutex lock; }; -static int mcp320x_adc_conversion(struct mcp320x *adc, u8 msg) +static int mcp320x_adc_conversion(struct mcp320x *adc, u8 channel, + bool differential, int device_index) { int ret; + __be16 buf; - adc->tx_buf = msg; - ret = spi_sync(adc->spi, &adc->msg); - if (ret < 0) - return ret; + adc->rx_buf[0] = 0; + adc->rx_buf[1] = 0; + adc->tx_buf = mcp320x_channel_to_tx_data(device_index, + channel, differential); + + if (device_index != mcp3001 && device_index != mcp3201) { + ret = spi_sync(adc->spi, &adc->msg); + if (ret < 0) + return ret; + } else { + ret = spi_read(adc->spi, (u8 *)&buf, 2); + if (ret < 0) + return ret; + } - return ((adc->rx_buf[0] & 0x3f) << 6) | - (adc->rx_buf[1] >> 2); + switch (device_index) { + case mcp3001: + return ((be16_to_cpu(buf) >> 3) & 0x03ff); + case mcp3002: + return (((adc->rx_buf[0] << 2) | + ((adc->rx_buf[1] & 0xC0) >> 6)) & 0x03ff); + case mcp3004: + case mcp3008: + return ((((adc->rx_buf[0] & 0x7f) << 3) | + ((adc->rx_buf[1] & 0xe0) >> 5)) & 0x03ff); + case mcp3201: + return (be16_to_cpu(buf) >> 1); + case mcp3202: + return ((adc->rx_buf[0] << 4) | ((adc->rx_buf[1] & 0xf0) >> 4)); + case mcp3204: + case mcp3208: + return (((adc->rx_buf[0] & 0x7f) << 5) | + ((adc->rx_buf[1] & 0xf8) >> 3)); + default: + return -EINVAL; + } } static int mcp320x_read_raw(struct iio_dev *indio_dev, @@ -55,18 +103,17 @@ static int mcp320x_read_raw(struct iio_dev *indio_dev, { struct mcp320x *adc = iio_priv(indio_dev); int ret = -EINVAL; + int device_index = 0; mutex_lock(&adc->lock); + device_index = spi_get_device_id(adc->spi)->driver_data; + switch (mask) { case IIO_CHAN_INFO_RAW: - if (channel->differential) - ret = mcp320x_adc_conversion(adc, - MCP_START_BIT | channel->address); - else - ret = mcp320x_adc_conversion(adc, - MCP_START_BIT | MCP_SINGLE_ENDED | - channel->address); + ret = mcp320x_adc_conversion(adc, channel->address, + channel->differential, device_index); + if (ret < 0) goto out; @@ -75,17 +122,23 @@ static int mcp320x_read_raw(struct iio_dev *indio_dev, break; case IIO_CHAN_INFO_SCALE: - /* Digital output code = (4096 * Vin) / Vref */ + /* + * Digital output code = (resolution * Vin) / Vref + * Get regulator output voltage in uV. + */ ret = regulator_get_voltage(adc->reg); if (ret < 0) goto out; + /* convert regulator output voltage to mV */ *val = ret / 1000; - *val2 = 12; - ret = IIO_VAL_FRACTIONAL_LOG2; - break; + if (device_index == mcp3001 || device_index == mcp3002 || + device_index == mcp3004 || device_index == mcp3008) + *val2 = 10; + else + *val2 = 12; - default: + ret = IIO_VAL_FRACTIONAL_LOG2; break; } @@ -117,6 +170,16 @@ out: .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \ } +static const struct iio_chan_spec mcp3201_channels[] = { + MCP320X_VOLTAGE_CHANNEL_DIFF(0), +}; + +static const struct iio_chan_spec mcp3202_channels[] = { + MCP320X_VOLTAGE_CHANNEL(0), + MCP320X_VOLTAGE_CHANNEL(1), + MCP320X_VOLTAGE_CHANNEL_DIFF(0), +}; + static const struct iio_chan_spec mcp3204_channels[] = { MCP320X_VOLTAGE_CHANNEL(0), MCP320X_VOLTAGE_CHANNEL(1), @@ -146,12 +209,36 @@ static const struct iio_info mcp320x_info = { .driver_module = THIS_MODULE, }; -struct mcp3208_chip_info { +struct mcp320x_chip_info { const struct iio_chan_spec *channels; unsigned int num_channels; }; -static const struct mcp3208_chip_info mcp3208_chip_infos[] = { +static const struct mcp320x_chip_info mcp320x_chip_infos[] = { + [mcp3001] = { + .channels = mcp3201_channels, + .num_channels = ARRAY_SIZE(mcp3201_channels) + }, + [mcp3002] = { + .channels = mcp3202_channels, + .num_channels = ARRAY_SIZE(mcp3202_channels) + }, + [mcp3004] = { + .channels = mcp3204_channels, + .num_channels = ARRAY_SIZE(mcp3204_channels) + }, + [mcp3008] = { + .channels = mcp3208_channels, + .num_channels = ARRAY_SIZE(mcp3208_channels) + }, + [mcp3201] = { + .channels = mcp3201_channels, + .num_channels = ARRAY_SIZE(mcp3201_channels) + }, + [mcp3202] = { + .channels = mcp3202_channels, + .num_channels = ARRAY_SIZE(mcp3202_channels) + }, [mcp3204] = { .channels = mcp3204_channels, .num_channels = ARRAY_SIZE(mcp3204_channels) @@ -162,11 +249,29 @@ static const struct mcp3208_chip_info mcp3208_chip_infos[] = { }, }; +static int mcp320x_channel_to_tx_data(int device_index, + const unsigned int channel, bool differential) +{ + switch (device_index) { + case mcp3002: + case mcp3202: + return(0x12 | (!differential << 3) | ((channel & 0x01) << 2)); + case mcp3004: + case mcp3204: + return(0x20 | (!differential << 4) | ((channel & 0x03) << 1)); + case mcp3008: + case mcp3208: + return(0x20 | (!differential << 4) | ((channel & 0x07) << 1)); + default: + return -EINVAL; + } +} + static int mcp320x_probe(struct spi_device *spi) { struct iio_dev *indio_dev; struct mcp320x *adc; - const struct mcp3208_chip_info *chip_info; + const struct mcp320x_chip_info *chip_info; int ret; indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); @@ -181,7 +286,7 @@ static int mcp320x_probe(struct spi_device *spi) indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->info = &mcp320x_info; - chip_info = &mcp3208_chip_infos[spi_get_device_id(spi)->driver_data]; + chip_info = &mcp320x_chip_infos[spi_get_device_id(spi)->driver_data]; indio_dev->channels = chip_info->channels; indio_dev->num_channels = chip_info->num_channels; @@ -226,7 +331,45 @@ static int mcp320x_remove(struct spi_device *spi) return 0; } +#if defined(CONFIG_OF) +static const struct of_device_id mcp320x_dt_ids[] = { + { + .compatible = "mcp3001", + .data = &mcp320x_chip_infos[mcp3001], + }, { + .compatible = "mcp3002", + .data = &mcp320x_chip_infos[mcp3002], + }, { + .compatible = "mcp3004", + .data = &mcp320x_chip_infos[mcp3004], + }, { + .compatible = "mcp3008", + .data = &mcp320x_chip_infos[mcp3004], + }, { + .compatible = "mcp3201", + .data = &mcp320x_chip_infos[mcp3201], + }, { + .compatible = "mcp3202", + .data = &mcp320x_chip_infos[mcp3202], + }, { + .compatible = "mcp3204", + .data = &mcp320x_chip_infos[mcp3204], + }, { + .compatible = "mcp3008", + .data = &mcp320x_chip_infos[mcp3208], + }, { + } +}; +MODULE_DEVICE_TABLE(of, mcp320x_dt_ids); +#endif + static const struct spi_device_id mcp320x_id[] = { + { "mcp3001", mcp3001 }, + { "mcp3002", mcp3002 }, + { "mcp3004", mcp3004 }, + { "mcp3008", mcp3008 }, + { "mcp3201", mcp3201 }, + { "mcp3202", mcp3202 }, { "mcp3204", mcp3204 }, { "mcp3208", mcp3208 }, { } @@ -245,5 +388,5 @@ static struct spi_driver mcp320x_driver = { module_spi_driver(mcp320x_driver); MODULE_AUTHOR("Oskar Andero <oskar.andero@xxxxxxxxx>"); -MODULE_DESCRIPTION("Microchip Technology MCP3204/08"); +MODULE_DESCRIPTION("Microchip Technology MCP3x01/02/04/08"); MODULE_LICENSE("GPL v2"); -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
