On 05/03/2013 11:00 AM, Lars-Peter Clausen wrote: > On 05/03/2013 11:58 AM, Oskar Andero wrote: >> This adds support for Microchip's 12 bit AD converters MCP3204 and >> MCP3208. These chips communicates over SPI and supports single-ended >> and pseudo-differential configurations. >> >> Cc: Jonathan Cameron <jic23@xxxxxxxxx> >> Cc: Lars-Peter Clausen <lars@xxxxxxxxxx> >> Signed-off-by: Oskar Andero <oskar.andero@xxxxxxxxx> > > Reviewed-by: Lars-Peter Clausen <lars@xxxxxxxxxx> Nice driver. Thanks Oskar and thanks Lars-Peter for your review work on this. Applied to the togreg branch of iio.git. Note this branch will be rebased before I send Greg a pull request (nature of where we are in the cycle!). Jonathan > >> --- >> drivers/iio/adc/Kconfig | 10 ++ >> drivers/iio/adc/Makefile | 1 + >> drivers/iio/adc/mcp320x.c | 257 ++++++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 268 insertions(+) >> create mode 100644 drivers/iio/adc/mcp320x.c >> >> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >> index ab0767e6..93129ec 100644 >> --- a/drivers/iio/adc/Kconfig >> +++ b/drivers/iio/adc/Kconfig >> @@ -133,6 +133,16 @@ config MAX1363 >> max11646, max11647) Provides direct access via sysfs and buffered >> data via the iio dev interface. >> >> +config MCP320X >> + tristate "Microchip Technology MCP3204/08" >> + depends on SPI >> + help >> + Say yes here to build support for Microchip Technology's MCP3204 or >> + MCP3208 analog to digital converter. >> + >> + This driver can also be built as a module. If so, the module will be >> + called mcp320x. >> + >> config TI_ADC081C >> tristate "Texas Instruments ADC081C021/027" >> depends on I2C >> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile >> index 0a825be..8f475d3 100644 >> --- a/drivers/iio/adc/Makefile >> +++ b/drivers/iio/adc/Makefile >> @@ -14,6 +14,7 @@ obj-$(CONFIG_AT91_ADC) += at91_adc.o >> obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o >> obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o >> obj-$(CONFIG_MAX1363) += max1363.o >> +obj-$(CONFIG_MCP320X) += mcp320x.o >> obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o >> obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o >> obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o >> diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c >> new file mode 100644 >> index 0000000..ebc0159 >> --- /dev/null >> +++ b/drivers/iio/adc/mcp320x.c >> @@ -0,0 +1,257 @@ >> +/* >> + * Copyright (C) 2013 Oskar Andero <oskar.andero@xxxxxxxxx> >> + * >> + * Driver for Microchip Technology's MCP3204 and MCP3208 ADC chips. >> + * Datasheet can be found here: >> + * http://ww1.microchip.com/downloads/en/devicedoc/21298c.pdf >> + * >> + * 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 >> + * published by the Free Software Foundation. >> + */ >> + >> +#include <linux/err.h> >> +#include <linux/spi/spi.h> >> +#include <linux/module.h> >> +#include <linux/iio/iio.h> >> +#include <linux/regulator/consumer.h> >> + >> +#define MCP_SINGLE_ENDED (1 << 3) >> +#define MCP_START_BIT (1 << 4) >> + >> +enum { >> + mcp3204, >> + mcp3208, >> +}; >> + >> +struct mcp320x { >> + struct spi_device *spi; >> + struct spi_message msg; >> + struct spi_transfer transfer[2]; >> + >> + u8 tx_buf; >> + u8 rx_buf[2]; >> + >> + struct regulator *reg; >> + struct mutex lock; >> +}; >> + >> +static int mcp320x_adc_conversion(struct mcp320x *adc, u8 msg) >> +{ >> + int ret; >> + >> + adc->tx_buf = msg; >> + ret = spi_sync(adc->spi, &adc->msg); >> + if (ret < 0) >> + return ret; >> + >> + return ((adc->rx_buf[0] & 0x3f) << 6) | >> + (adc->rx_buf[1] >> 2); >> +} >> + >> +static int mcp320x_read_raw(struct iio_dev *indio_dev, >> + struct iio_chan_spec const *channel, int *val, >> + int *val2, long mask) >> +{ >> + struct mcp320x *adc = iio_priv(indio_dev); >> + int ret = -EINVAL; >> + >> + mutex_lock(&adc->lock); >> + >> + 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); >> + if (ret < 0) >> + goto out; >> + >> + *val = ret; >> + ret = IIO_VAL_INT; >> + break; >> + >> + case IIO_CHAN_INFO_SCALE: >> + /* Digital output code = (4096 * Vin) / Vref */ >> + ret = regulator_get_voltage(adc->reg); >> + if (ret < 0) >> + goto out; >> + >> + *val = ret / 1000; >> + *val2 = 12; >> + ret = IIO_VAL_FRACTIONAL_LOG2; >> + break; >> + >> + default: >> + break; >> + } >> + >> +out: >> + mutex_unlock(&adc->lock); >> + >> + return ret; >> +} >> + >> +#define MCP320X_VOLTAGE_CHANNEL(num) \ >> + { \ >> + .type = IIO_VOLTAGE, \ >> + .indexed = 1, \ >> + .channel = (num), \ >> + .address = (num), \ >> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ >> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \ >> + } >> + >> +#define MCP320X_VOLTAGE_CHANNEL_DIFF(num) \ >> + { \ >> + .type = IIO_VOLTAGE, \ >> + .indexed = 1, \ >> + .channel = (num * 2), \ >> + .channel2 = (num * 2 + 1), \ >> + .address = (num * 2), \ >> + .differential = 1, \ >> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ >> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \ >> + } >> + >> +static const struct iio_chan_spec mcp3204_channels[] = { >> + MCP320X_VOLTAGE_CHANNEL(0), >> + MCP320X_VOLTAGE_CHANNEL(1), >> + MCP320X_VOLTAGE_CHANNEL(2), >> + MCP320X_VOLTAGE_CHANNEL(3), >> + MCP320X_VOLTAGE_CHANNEL_DIFF(0), >> + MCP320X_VOLTAGE_CHANNEL_DIFF(1), >> +}; >> + >> +static const struct iio_chan_spec mcp3208_channels[] = { >> + MCP320X_VOLTAGE_CHANNEL(0), >> + MCP320X_VOLTAGE_CHANNEL(1), >> + MCP320X_VOLTAGE_CHANNEL(2), >> + MCP320X_VOLTAGE_CHANNEL(3), >> + MCP320X_VOLTAGE_CHANNEL(4), >> + MCP320X_VOLTAGE_CHANNEL(5), >> + MCP320X_VOLTAGE_CHANNEL(6), >> + MCP320X_VOLTAGE_CHANNEL(7), >> + MCP320X_VOLTAGE_CHANNEL_DIFF(0), >> + MCP320X_VOLTAGE_CHANNEL_DIFF(1), >> + MCP320X_VOLTAGE_CHANNEL_DIFF(2), >> + MCP320X_VOLTAGE_CHANNEL_DIFF(3), >> +}; >> + >> +static const struct iio_info mcp320x_info = { >> + .read_raw = mcp320x_read_raw, >> + .driver_module = THIS_MODULE, >> +}; >> + >> +struct mcp3208_chip_info { >> + const struct iio_chan_spec *channels; >> + unsigned int num_channels; >> +}; >> + >> +static const struct mcp3208_chip_info mcp3208_chip_infos[] = { >> + [mcp3204] = { >> + .channels = mcp3204_channels, >> + .num_channels = ARRAY_SIZE(mcp3204_channels) >> + }, >> + [mcp3208] = { >> + .channels = mcp3208_channels, >> + .num_channels = ARRAY_SIZE(mcp3208_channels) >> + }, >> +}; >> + >> +static int mcp320x_probe(struct spi_device *spi) >> +{ >> + struct iio_dev *indio_dev; >> + struct mcp320x *adc; >> + const struct mcp3208_chip_info *chip_info; >> + int ret; >> + >> + indio_dev = iio_device_alloc(sizeof(*adc)); >> + if (!indio_dev) >> + return -ENOMEM; >> + >> + adc = iio_priv(indio_dev); >> + adc->spi = spi; >> + >> + indio_dev->dev.parent = &spi->dev; >> + indio_dev->name = spi_get_device_id(spi)->name; >> + indio_dev->modes = INDIO_DIRECT_MODE; >> + indio_dev->info = &mcp320x_info; >> + >> + chip_info = &mcp3208_chip_infos[spi_get_device_id(spi)->driver_data]; >> + indio_dev->channels = chip_info->channels; >> + indio_dev->num_channels = chip_info->num_channels; >> + >> + adc->transfer[0].tx_buf = &adc->tx_buf; >> + adc->transfer[0].len = sizeof(adc->tx_buf); >> + adc->transfer[1].rx_buf = adc->rx_buf; >> + adc->transfer[1].len = sizeof(adc->rx_buf); >> + >> + spi_message_init_with_transfers(&adc->msg, adc->transfer, >> + ARRAY_SIZE(adc->transfer)); >> + >> + adc->reg = regulator_get(&spi->dev, "vref"); >> + if (IS_ERR(adc->reg)) { >> + ret = PTR_ERR(adc->reg); >> + goto iio_free; >> + } >> + >> + ret = regulator_enable(adc->reg); >> + if (ret < 0) >> + goto reg_free; >> + >> + mutex_init(&adc->lock); >> + >> + ret = iio_device_register(indio_dev); >> + if (ret < 0) >> + goto reg_disable; >> + >> + return 0; >> + >> +reg_disable: >> + regulator_disable(adc->reg); >> +reg_free: >> + regulator_put(adc->reg); >> +iio_free: >> + iio_device_free(indio_dev); >> + >> + return ret; >> +} >> + >> +static int mcp320x_remove(struct spi_device *spi) >> +{ >> + struct iio_dev *indio_dev = spi_get_drvdata(spi); >> + struct mcp320x *adc = iio_priv(indio_dev); >> + >> + iio_device_unregister(indio_dev); >> + regulator_disable(adc->reg); >> + regulator_put(adc->reg); >> + iio_device_free(indio_dev); >> + >> + return 0; >> +} >> + >> +static const struct spi_device_id mcp320x_id[] = { >> + { "mcp3204", mcp3204 }, >> + { "mcp3208", mcp3208 }, >> + { } >> +}; >> +MODULE_DEVICE_TABLE(spi, mcp320x_id); >> + >> +static struct spi_driver mcp320x_driver = { >> + .driver = { >> + .name = "mcp320x", >> + .owner = THIS_MODULE, >> + }, >> + .probe = mcp320x_probe, >> + .remove = mcp320x_remove, >> + .id_table = mcp320x_id, >> +}; >> +module_spi_driver(mcp320x_driver); >> + >> +MODULE_AUTHOR("Oskar Andero <oskar.andero@xxxxxxxxx>"); >> +MODULE_DESCRIPTION("Microchip Technology MCP3204/08"); >> +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
