Add dummy driver to support sigma delta modulators.
Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@st.com --- drivers/iio/adc/Kconfig | 11 ++++ drivers/iio/adc/Makefile | 1 + drivers/iio/adc/simple_sd_adc.c | 112 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 124 insertions(+) create mode 100644 drivers/iio/adc/simple_sd_adc.c
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index e0b3c09..d4366ac 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -419,6 +419,17 @@ config ROCKCHIP_SARADC To compile this driver as a module, choose M here: the module will be called rockchip_saradc.
+config SIMPLE_SD_ADC + tristate "Simple sigma delta modulator" + depends on OF + select IIO_BUFFER + select IIO_TRIGGERED_BUFFER + help + Select this option to enables generic sigma delta modulator. + + This driver can also be built as a module. If so, the module + will be called simple-sd-adc. + config STM32_ADC_CORE tristate "STMicroelectronics STM32 adc core" depends on ARCH_STM32 || COMPILE_TEST diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 8e02a94..bd67144 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -57,3 +57,4 @@ obj-$(CONFIG_VF610_ADC) += vf610_adc.o obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o xilinx-xadc-y := xilinx-xadc-core.o xilinx-xadc-events.o obj-$(CONFIG_XILINX_XADC) += xilinx-xadc.o +obj-$(CONFIG_SIMPLE_SD_ADC) += simple_sd_adc.o diff --git a/drivers/iio/adc/simple_sd_adc.c b/drivers/iio/adc/simple_sd_adc.c new file mode 100644 index 0000000..4bc8b3c --- /dev/null +++ b/drivers/iio/adc/simple_sd_adc.c @@ -0,0 +1,112 @@ +/* + * simple sigma delta modulator driver + * + * Copyright (C) 2016, STMicroelectronics - All Rights Reserved + * Author: Arnaud Pouliquen arnaud.pouliquen@st.com. + * + * License type: GPLv2 + * + * 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. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. + * See the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see http://www.gnu.org/licenses/. + */ + +#include <linux/iio/iio.h> +#include <linux/module.h> +#include <linux/of_device.h> + +#include <linux/iio/triggered_buffer.h> + +static int simple_sd_of_xlate(struct iio_dev *iio, + const struct of_phandle_args *iiospec) +{ + dev_dbg(&iio->dev, "%s:\n", __func__); + if (iiospec->args[0] != 0) { + dev_err(&iio->dev, "Only one channel supported\n"); + return -EINVAL; + } + + return 0; +} + +static const struct iio_info simple_sd_iio_info = { + .of_xlate = simple_sd_of_xlate, +}; + +static const struct iio_buffer_setup_ops simple_sd_buffer_ops; + +static int simple_sd_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct iio_dev *iio; + struct iio_chan_spec *ch; + + dev_dbg(&pdev->dev, "%s:\n", __func__); + iio = devm_iio_device_alloc(dev, 0); + if (!iio) + return -ENOMEM; + + /* Define one channel */ + ch = devm_kzalloc(&iio->dev, sizeof(*ch), GFP_KERNEL); + if (!ch) + return -ENOMEM; + + iio->dev.parent = dev; + iio->dev.of_node = dev->of_node; + iio->name = dev_name(dev); + iio->info = &simple_sd_iio_info; + iio->modes = INDIO_BUFFER_HARDWARE; + + ch->type = IIO_VOLTAGE; + ch->indexed = 1; + ch->scan_index = 0; + ch->scan_type.sign = 'u'; + ch->scan_type.realbits = 1; + ch->scan_type.storagebits = 1; + ch->scan_type.shift = 0; + + iio->num_channels = 1; + iio->channels = ch; + + platform_set_drvdata(pdev, iio); + + return iio_device_register(iio); +} + +static int simple_sd_remove(struct platform_device *pdev) +{ + struct iio_dev *iio = platform_get_drvdata(pdev); + + iio_device_unregister(iio); + + return 0; +} + +static const struct of_device_id sd_adc_of_match[] = { + { .compatible = "sd-modulator" }, + { } +}; +MODULE_DEVICE_TABLE(of, adc081c_of_match); + +static struct platform_driver simple_sd_adc = { + .driver = { + .name = "simple_sd_adc", + .of_match_table = of_match_ptr(sd_adc_of_match), + }, + .probe = simple_sd_probe, + .remove = simple_sd_remove, +}; + +module_platform_driver(simple_sd_adc); + +MODULE_DESCRIPTION("simple signma delta modulator"); +MODULE_AUTHOR("Arnaud Pouliquen arnaud.pouliquen@st.com"); +MODULE_LICENSE("GPL v2");