On Tue, 20 Sep 2016, Lars-Peter Clausen wrote: > Add support for the AD7766, AD7766-1, AD7766-2, AD7767, AD7767-1, AD7767-2 > Analog to Digital converters. It's a family of single channel 24-bit SAR > ADCs. They are all digital interface compatible and the main difference is > the internal decimation rate and analog performance. For communication with > the host processor a SPI interface is used. looks good, nitpicking below > In addition the part has a data ready pin that is pulsed for one MCLK cycle > when a conversion has completed and can be used as a IIO trigger. > > Datasheets: > http://www.analog.com/media/en/technical-documentation/data-sheets/AD7766.pdf > http://www.analog.com/media/en/technical-documentation/data-sheets/AD7767.pdf > > Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx> > --- > drivers/iio/adc/Kconfig | 10 ++ > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/ad7766.c | 342 +++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 353 insertions(+) > create mode 100644 drivers/iio/adc/ad7766.c > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 7edcf32..c9c38e4 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -58,6 +58,16 @@ config AD7476 > To compile this driver as a module, choose M here: the > module will be called ad7476. > > +config AD7766 > + tristate "Analog Devices AD7766/AD7767 ADC driver" > + depends on SPI_MASTER > + help > + Say yes here to build support for Analog Devices AD7766, AD7766-1, > + AD7766-2, AD7767, AD7767-1, AD7767-2 SPI analog to digital converters. extra space before 'SPI' > + > + To compile this driver as a module, choose M here: the module will be > + called ad7766. > + > config AD7791 > tristate "Analog Devices AD7791 ADC driver" > depends on SPI > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index 7a40c04..96894b3 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -9,6 +9,7 @@ obj-$(CONFIG_AD7291) += ad7291.o > obj-$(CONFIG_AD7298) += ad7298.o > obj-$(CONFIG_AD7923) += ad7923.o > obj-$(CONFIG_AD7476) += ad7476.o > +obj-$(CONFIG_AD7766) += ad7766.o > obj-$(CONFIG_AD7791) += ad7791.o > obj-$(CONFIG_AD7793) += ad7793.o > obj-$(CONFIG_AD7887) += ad7887.o > diff --git a/drivers/iio/adc/ad7766.c b/drivers/iio/adc/ad7766.c > new file mode 100644 > index 0000000..4d82f9d > --- /dev/null > +++ b/drivers/iio/adc/ad7766.c > @@ -0,0 +1,342 @@ > +/* > + * AD7766/AD7767 SPI ADC driver > + * > + * Copyright 2016 Analog Devices Inc. > + * > + * Licensed under the GPL-2 or later. > + */ > + > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/device.h> > +#include <linux/err.h> > +#include <linux/gpio/consumer.h> > +#include <linux/module.h> > +#include <linux/regulator/consumer.h> > +#include <linux/slab.h> > +#include <linux/spi/spi.h> > + > +#include <linux/iio/iio.h> > +#include <linux/iio/buffer.h> > +#include <linux/iio/trigger.h> > +#include <linux/iio/trigger_consumer.h> > +#include <linux/iio/triggered_buffer.h> > + > +struct ad7766_chip_info { > + unsigned int decimation_factor; > +}; > + > +struct ad7766 { > + const struct ad7766_chip_info *chip_info; > + struct spi_device *spi; > + struct clk *mclk; > + struct gpio_desc *pd_gpio; > + struct regulator_bulk_data reg[3]; > + > + struct iio_trigger *trig; > + > + struct spi_transfer xfer; > + struct spi_message msg; > + > + /* > + * DMA (thus cache coherency maintenance) requires the > + * transfer buffers to live in their own cache lines. > + * Make the buffer large enough for one 24 bit sample and one 64 bit > + * aligned 64 bit timestamp. > + */ > + unsigned char data[ALIGN(3, sizeof(s64)) + sizeof(s64)] > + ____cacheline_aligned; > +}; > + > +enum ad7766_device_ids { > + ID_AD7766, > + ID_AD7766_1, > + ID_AD7766_2, 7767 missing? maybe worth a comment > +}; > + > +static irqreturn_t ad7766_trigger_handler(int irq, void *p) > +{ > + struct iio_poll_func *pf = p; > + struct iio_dev *indio_dev = pf->indio_dev; > + struct ad7766 *ad7766 = iio_priv(indio_dev); > + int ret; > + > + ret = spi_sync(ad7766->spi, &ad7766->msg); > + if (ret < 0) > + goto done; > + > + iio_push_to_buffers_with_timestamp(indio_dev, ad7766->data, > + pf->timestamp); > +done: > + iio_trigger_notify_done(indio_dev->trig); > + > + return IRQ_HANDLED; > +} > + > +static int ad7766_preenable(struct iio_dev *indio_dev) > +{ > + struct ad7766 *ad7766 = iio_priv(indio_dev); > + int ret; > + > + ret = regulator_bulk_enable(ARRAY_SIZE(ad7766->reg), ad7766->reg); two blanks before last argument > + if (ret < 0) { > + dev_err(&ad7766->spi->dev, "Failed to enable supplies: %d\n", > + ret); > + return ret; > + } > + > + ret = clk_prepare_enable(ad7766->mclk); > + if (ret < 0) { > + dev_err(&ad7766->spi->dev, "Failed to enable MCLK: %d\n", ret); > + regulator_bulk_disable(ARRAY_SIZE(ad7766->reg), ad7766->reg); > + return ret; > + } > + > + if (ad7766->pd_gpio) > + gpiod_set_value(ad7766->pd_gpio, 0); > + > + return 0; > +} > + > +static int ad7766_postdisable(struct iio_dev *indio_dev) > +{ > + struct ad7766 *ad7766 = iio_priv(indio_dev); > + > + if (ad7766->pd_gpio) > + gpiod_set_value(ad7766->pd_gpio, 1); > + > + /* > + * The PD pin is synchronous to the clock, so give it some time to > + * notice the change before we disable the clock. > + */ > + msleep(20); > + > + clk_disable_unprepare(ad7766->mclk); > + regulator_bulk_disable(ARRAY_SIZE(ad7766->reg), ad7766->reg); > + > + return 0; > +} > + > +static int ad7766_read_raw(struct iio_dev *indio_dev, > + const struct iio_chan_spec *chan, int *val, int *val2, long info) > +{ > + struct ad7766 *ad7766 = iio_priv(indio_dev); > + int scale_uv; > + > + switch (info) { > + case IIO_CHAN_INFO_SCALE: > + scale_uv = regulator_get_voltage(ad7766->reg[2].consumer); could use a #define for the index 2, VREF_something or so > + if (scale_uv < 0) > + return scale_uv; > + *val = scale_uv / 1000; > + *val2 = chan->scan_type.realbits; > + return IIO_VAL_FRACTIONAL_LOG2; > + case IIO_CHAN_INFO_SAMP_FREQ: > + *val = clk_get_rate(ad7766->mclk) / > + ad7766->chip_info->decimation_factor; > + return IIO_VAL_INT; > + } > + return -EINVAL; > +} > + > +static const struct iio_chan_spec ad7766_channels[] = { > + { > + .type = IIO_VOLTAGE, > + .indexed = 1, have only one channel and still indexed? > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), > + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), > + .scan_type = { > + .sign = 's', > + .realbits = 24, > + .storagebits = 32, > + .shift = 0, .shift not strictly necessary > + .endianness = IIO_BE, > + }, > + }, > + IIO_CHAN_SOFT_TIMESTAMP(1), > +}; > + > +static const struct ad7766_chip_info ad7766_chip_info[] = { > + [ID_AD7766] = { > + .decimation_factor = 8, > + }, > + [ID_AD7766_1] = { > + .decimation_factor = 16, > + }, > + [ID_AD7766_2] = { > + .decimation_factor = 32, > + }, > +}; > + > +static const struct iio_buffer_setup_ops ad7766_buffer_setup_ops = { > + .preenable = &ad7766_preenable, > + .postenable = &iio_triggered_buffer_postenable, > + .predisable = &iio_triggered_buffer_predisable, > + .postdisable = &ad7766_postdisable, > +}; > + > +static const struct iio_info ad7766_info = { > + .driver_module = THIS_MODULE, > + .read_raw = &ad7766_read_raw, > +}; > + > +static irqreturn_t ad7766_irq(int irq, void *private) > +{ > + iio_trigger_poll(private); > + return IRQ_HANDLED; > +} > + > +static int ad7766_set_trigger_state(struct iio_trigger *trig, bool enable) > +{ > + struct ad7766 *ad7766 = iio_trigger_get_drvdata(trig); > + > + if (enable) > + enable_irq(ad7766->spi->irq); > + else > + disable_irq(ad7766->spi->irq); > + > + return 0; > +} > + > +static const struct iio_trigger_ops ad7766_trigger_ops = { > + .owner = THIS_MODULE, > + .set_trigger_state = ad7766_set_trigger_state, > +}; > + > +static int ad7766_probe(struct spi_device *spi) > +{ > + const struct spi_device_id *id = spi_get_device_id(spi); > + struct iio_dev *indio_dev; > + struct ad7766 *ad7766; > + int ret; > + > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*ad7766)); > + if (!indio_dev) > + return -ENOMEM; > + > + ad7766 = iio_priv(indio_dev); > + ad7766->chip_info = &ad7766_chip_info[id->driver_data]; > + > + ad7766->mclk = devm_clk_get(&spi->dev, "mclk"); > + if (IS_ERR(ad7766->mclk)) > + return PTR_ERR(ad7766->mclk); > + > + ad7766->reg[0].supply = "avdd"; > + ad7766->reg[1].supply = "dvdd"; > + ad7766->reg[2].supply = "vref"; > + > + ret = devm_regulator_bulk_get(&spi->dev, ARRAY_SIZE(ad7766->reg), > + ad7766->reg); > + if (IS_ERR(ad7766->reg)) > + return PTR_ERR(ad7766->reg); > + > + ad7766->pd_gpio = devm_gpiod_get_optional(&spi->dev, "powerdown", > + GPIOD_OUT_HIGH); > + if (IS_ERR(ad7766->pd_gpio)) > + return PTR_ERR(ad7766->pd_gpio); > + > + indio_dev->dev.parent = &spi->dev; > + indio_dev->name = spi_get_device_id(spi)->name; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->channels = ad7766_channels; > + indio_dev->num_channels = ARRAY_SIZE(ad7766_channels); > + indio_dev->info = &ad7766_info; > + > + if (spi->irq > 0) { > + ad7766->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d", > + indio_dev->name, indio_dev->id); > + if (!ad7766->trig) > + return -ENOMEM; > + > + ad7766->trig->ops = &ad7766_trigger_ops; > + iio_trigger_set_drvdata(ad7766->trig, ad7766); > + > + ret = request_irq(spi->irq, ad7766_irq, IRQF_TRIGGER_FALLING, > + dev_name(&spi->dev), ad7766->trig); > + if (ret < 0) > + return ret; > + > + /* > + * The device generates interrupts as long as it is powered up. > + * Some platforms might not allow the option to power it down so > + * disable the interrupt to avoid extra load on the system > + */ > + disable_irq(spi->irq); > + > + ret = iio_trigger_register(ad7766->trig); > + if (ret) > + goto err_free_irq; > + } > + > + spi_set_drvdata(spi, indio_dev); > + > + ad7766->spi = spi; > + > + /* First byte always 0 */ > + ad7766->xfer.rx_buf = &ad7766->data[1]; > + ad7766->xfer.len = 3; > + > + spi_message_init(&ad7766->msg); > + spi_message_add_tail(&ad7766->xfer, &ad7766->msg); > + > + ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, > + &ad7766_trigger_handler, &ad7766_buffer_setup_ops); > + if (ret) > + goto err_trigger_unregister; > + > + ret = iio_device_register(indio_dev); > + if (ret) > + goto err_triggered_buffer_cleanup; > + return 0; > + > +err_triggered_buffer_cleanup: > + iio_triggered_buffer_cleanup(indio_dev); > +err_trigger_unregister: > + if (spi->irq > 0) > + iio_trigger_unregister(ad7766->trig); > +err_free_irq: > + if (spi->irq > 0) > + free_irq(spi->irq, ad7766->trig); > + > + return ret; > +} > + > +static int ad7766_remove(struct spi_device *spi) > +{ > + struct iio_dev *indio_dev = spi_get_drvdata(spi); > + struct ad7766 *ad7766 = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + iio_triggered_buffer_cleanup(indio_dev); > + if (spi->irq > 0) { > + iio_trigger_unregister(ad7766->trig); > + free_irq(spi->irq, ad7766->trig); > + } > + > + return 0; > +} > + > +static const struct spi_device_id ad7766_id[] = { > + {"ad7766", ID_AD7766}, > + {"ad7766-1", ID_AD7766_1}, > + {"ad7766-2", ID_AD7766_2}, > + {"ad7767", ID_AD7766}, > + {"ad7767-1", ID_AD7766_1}, > + {"ad7767-2", ID_AD7766_2}, > + {} > +}; > +MODULE_DEVICE_TABLE(spi, ad7766_id); > + > +static struct spi_driver ad7766_driver = { > + .driver = { > + .name = "ad7766", > + }, > + .probe = ad7766_probe, > + .remove = ad7766_remove, > + .id_table = ad7766_id, > +}; > +module_spi_driver(ad7766_driver); > + > +MODULE_AUTHOR("Lars-Peter Clausen <lars@xxxxxxxxxx>"); > +MODULE_DESCRIPTION("Analog Devices AD7766 and AD7767 ADCs driver support"); > +MODULE_LICENSE("GPL v2"); > -- Peter Meerwald-Stadler +43-664-2444418 (mobile) -- 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
