On Sb, 2019-01-19 at 17:55 +0000, Jonathan Cameron wrote: > Use caution when clicking links or attachments as this email originated > outside of Analog Devices. > > > On Tue, 15 Jan 2019 14:33:11 +0200 > Stefan Popa <stefan.popa@xxxxxxxxxx> wrote: > > > > > The ad7768-1 is a single channel, precision 24-bit analog to digital > > converter (ADC). > > > > This basic patch configures the device in fast mode, with 32 kSPS and > > leaves the default sinc5 filter. > > > > Two data conversion modes are made available. When data is retrieved by > > using the read_raw attribute, one shot single conversion mode is set. > > The continuous conversion mode is enabled when the triggered buffer > > mechanism is used. To assure correct data retrieval, the driver waits > > for the interrupt triggered by the low to high transition of the DRDY > > pin. > > > > Datasheets: > > Link: https://www.analog.com/media/en/technical-documentation/data-shee > > ts/ad7768-1.pdf > > > > Signed-off-by: Stefan Popa <stefan.popa@xxxxxxxxxx> > Hi Stefan, > > Driver is fine, but the licensing needs clarification. > "GPL" in module license means GPL v2 or later, but the SPDX is GPL v2 > only. > > I had a question out to Michael for some of his older drivers on > exactly this. We need to fix this one and tidy those up to > be clear one way or the other. > If you just let me know which one is right, I'll fix it up rather than > you having > to send a v3. > > Thanks, > > Jonathan > Hi Jonathan, Thank you for your review. Michael informed me that our drivers are typically GPL v2 only. I will check the other drivers that we've sent upstream and provide a patch to fix the wrong licenses. -Stefan > > > > --- > > Changes in v2: > > - Added values to all the elements of ad7768_pwrmode enum. > > - Removed the ad7768_ids enum, as the driver supports only one > > device. > > - Added a new data union which is part of the ad7768_state > > struct. This > > union, now includes a d8 field. > > - Used spi_write_then_read() in ad7768_spi_reg_read(). > > - Called spi_read() instead of spi_sync_transfer() in > > ad7768_trigger_handler(). > > - Used the devm_request_irq() instead of > > devm_request_threaded_irq(); called > > iio_trigger_poll() instead of iio_trigger_poll_chained(). > > > > MAINTAINERS | 7 + > > drivers/iio/adc/Kconfig | 13 ++ > > drivers/iio/adc/Makefile | 1 + > > drivers/iio/adc/ad7768-1.c | 459 > > +++++++++++++++++++++++++++++++++++++++++++++ > > 4 files changed, 480 insertions(+) > > create mode 100644 drivers/iio/adc/ad7768-1.c > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > index d039f66..3ba3811 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -862,6 +862,13 @@ S: Supported > > F: drivers/iio/adc/ad7606.c > > F: Documentation/devicetree/bindings/iio/adc/ad7606.txt > > > > +ANALOG DEVICES INC AD7768-1 DRIVER > > +M: Stefan Popa <stefan.popa@xxxxxxxxxx> > > +L: linux-iio@xxxxxxxxxxxxxxx > > +W: http://ez.analog.com/community/linux-device-drivers > > +S: Supported > > +F: drivers/iio/adc/ad7768-1.c > > + > > ANALOG DEVICES INC AD9389B DRIVER > > M: Hans Verkuil <hans.verkuil@xxxxxxxxx> > > L: linux-media@xxxxxxxxxxxxxxx > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > > index f3cc7a3..6c19dfe 100644 > > --- a/drivers/iio/adc/Kconfig > > +++ b/drivers/iio/adc/Kconfig > > @@ -108,6 +108,19 @@ config AD7766 > > To compile this driver as a module, choose M here: the module > > will be > > called ad7766. > > > > +config AD7768_1 > > + tristate "Analog Devices AD7768-1 ADC driver" > > + depends on SPI > > + select IIO_BUFFER > > + select IIO_TRIGGER > > + select IIO_TRIGGERED_BUFFER > > + help > > + Say yes here to build support for Analog Devices AD7768-1 SPI > > + simultaneously sampling sigma-delta analog to digital converter > > (ADC). > > + > > + To compile this driver as a module, choose M here: the module > > will be > > + called ad7768-1. > > + > > config AD7791 > > tristate "Analog Devices AD7791 ADC driver" > > depends on SPI > > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > > index ea50313..9d50f7b 100644 > > --- a/drivers/iio/adc/Makefile > > +++ b/drivers/iio/adc/Makefile > > @@ -15,6 +15,7 @@ obj-$(CONFIG_AD7606_IFACE_PARALLEL) += ad7606_par.o > > obj-$(CONFIG_AD7606_IFACE_SPI) += ad7606_spi.o > > obj-$(CONFIG_AD7606) += ad7606.o > > obj-$(CONFIG_AD7766) += ad7766.o > > +obj-$(CONFIG_AD7768_1) += ad7768-1.o > > obj-$(CONFIG_AD7791) += ad7791.o > > obj-$(CONFIG_AD7793) += ad7793.o > > obj-$(CONFIG_AD7887) += ad7887.o > > diff --git a/drivers/iio/adc/ad7768-1.c b/drivers/iio/adc/ad7768-1.c > > new file mode 100644 > > index 0000000..fdcb966 > > --- /dev/null > > +++ b/drivers/iio/adc/ad7768-1.c > > @@ -0,0 +1,459 @@ > > +// SPDX-License-Identifier: GPL-2.0 > This is GPl v2 only. The MODULE_LICENSE is GPL v2 or later. > > > > > +/* > > + * Analog Devices AD7768-1 SPI ADC driver > > + * > > + * Copyright 2017 Analog Devices Inc. > > + */ > > +#include <linux/bitfield.h> > > +#include <linux/clk.h> > > +#include <linux/delay.h> > > +#include <linux/device.h> > > +#include <linux/err.h> > > +#include <linux/kernel.h> > > +#include <linux/module.h> > > +#include <linux/regulator/consumer.h> > > +#include <linux/sysfs.h> > > +#include <linux/spi/spi.h> > > + > > +#include <linux/iio/buffer.h> > > +#include <linux/iio/iio.h> > > +#include <linux/iio/sysfs.h> > > +#include <linux/iio/trigger.h> > > +#include <linux/iio/triggered_buffer.h> > > +#include <linux/iio/trigger_consumer.h> > > + > > +/* AD7768 registers definition */ > > +#define AD7768_REG_CHIP_TYPE 0x3 > > +#define AD7768_REG_PROD_ID_L 0x4 > > +#define AD7768_REG_PROD_ID_H 0x5 > > +#define AD7768_REG_CHIP_GRADE 0x6 > > +#define AD7768_REG_SCRATCH_PAD 0x0A > > +#define AD7768_REG_VENDOR_L 0x0C > > +#define AD7768_REG_VENDOR_H 0x0D > > +#define AD7768_REG_INTERFACE_FORMAT 0x14 > > +#define AD7768_REG_POWER_CLOCK 0x15 > > +#define AD7768_REG_ANALOG 0x16 > > +#define AD7768_REG_ANALOG2 0x17 > > +#define AD7768_REG_CONVERSION 0x18 > > +#define AD7768_REG_DIGITAL_FILTER 0x19 > > +#define AD7768_REG_SINC3_DEC_RATE_MSB 0x1A > > +#define AD7768_REG_SINC3_DEC_RATE_LSB 0x1B > > +#define AD7768_REG_DUTY_CYCLE_RATIO 0x1C > > +#define AD7768_REG_SYNC_RESET 0x1D > > +#define AD7768_REG_GPIO_CONTROL 0x1E > > +#define AD7768_REG_GPIO_WRITE 0x1F > > +#define AD7768_REG_GPIO_READ 0x20 > > +#define AD7768_REG_OFFSET_HI 0x21 > > +#define AD7768_REG_OFFSET_MID 0x22 > > +#define AD7768_REG_OFFSET_LO 0x23 > > +#define AD7768_REG_GAIN_HI 0x24 > > +#define AD7768_REG_GAIN_MID 0x25 > > +#define AD7768_REG_GAIN_LO 0x26 > > +#define AD7768_REG_SPI_DIAG_ENABLE 0x28 > > +#define AD7768_REG_ADC_DIAG_ENABLE 0x29 > > +#define AD7768_REG_DIG_DIAG_ENABLE 0x2A > > +#define AD7768_REG_ADC_DATA 0x2C > > +#define AD7768_REG_MASTER_STATUS 0x2D > > +#define AD7768_REG_SPI_DIAG_STATUS 0x2E > > +#define AD7768_REG_ADC_DIAG_STATUS 0x2F > > +#define AD7768_REG_DIG_DIAG_STATUS 0x30 > > +#define AD7768_REG_MCLK_COUNTER 0x31 > > + > > +/* AD7768_REG_CONVERSION */ > > +#define AD7768_CONV_MODE_MSK GENMASK(2, 0) > > +#define AD7768_CONV_MODE(x) FIELD_PREP(AD7768_CONV_MODE_MSK, > > x) > > + > > +#define AD7768_RD_FLAG_MSK(x) (BIT(6) | ((x) & 0x3F)) > > +#define AD7768_WR_FLAG_MSK(x) ((x) & 0x3F) > > + > > +enum ad7768_conv_mode { > > + AD7768_CONTINUOUS, > > + AD7768_ONE_SHOT, > > + AD7768_SINGLE, > > + AD7768_PERIODIC, > > + AD7768_STANDBY > > +}; > > + > > +enum ad7768_pwrmode { > > + AD7768_ECO_MODE = 0, > > + AD7768_MED_MODE = 2, > > + AD7768_FAST_MODE = 3 > > +}; > > + > > +static const struct iio_chan_spec ad7768_channels[] = { > > + { > > + .type = IIO_VOLTAGE, > > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), > > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), > > + .indexed = 1, > > + .channel = 0, > > + .scan_index = 0, > > + .scan_type = { > > + .sign = 'u', > > + .realbits = 24, > > + .storagebits = 32, > > + .shift = 8, > > + .endianness = IIO_BE, > > + }, > > + }, > > +}; > > + > > +struct ad7768_state { > > + struct spi_device *spi; > > + struct regulator *vref; > > + struct mutex lock; > > + struct completion completion; > > + struct iio_trigger *trig; > > + /* > > + * DMA (thus cache coherency maintenance) requires the > > + * transfer buffers to live in their own cache lines. > > + */ > > + union { > > + __be32 d32; > > + u8 d8[2]; > > + } data ____cacheline_aligned; > > +}; > > + > > +static int ad7768_spi_reg_read(struct ad7768_state *st, unsigned int > > addr, > > + unsigned int len) > > +{ > > + unsigned int shift; > > + int ret; > > + > > + shift = 32 - (8 * len); > > + st->data.d8[0] = AD7768_RD_FLAG_MSK(addr); > > + > > + ret = spi_write_then_read(st->spi, st->data.d8, 1, > > + &st->data.d32, len); > > + if (ret < 0) > > + return ret; > > + > > + return (be32_to_cpu(st->data.d32) >> shift); > > +} > > + > > +static int ad7768_spi_reg_write(struct ad7768_state *st, > > + unsigned int addr, > > + unsigned int val) > > +{ > > + st->data.d8[0] = AD7768_WR_FLAG_MSK(addr); > > + st->data.d8[1] = val & 0xFF; > > + > > + return spi_write(st->spi, st->data.d8, 2); > > +} > > + > > +static int ad7768_set_mode(struct ad7768_state *st, > > + enum ad7768_conv_mode mode) > > +{ > > + int regval; > > + > > + regval = ad7768_spi_reg_read(st, AD7768_REG_CONVERSION, 1); > > + if (regval < 0) > > + return regval; > > + > > + regval &= ~AD7768_CONV_MODE_MSK; > > + regval |= AD7768_CONV_MODE(mode); > > + > > + return ad7768_spi_reg_write(st, AD7768_REG_CONVERSION, regval); > > +} > > + > > +static int ad7768_scan_direct(struct iio_dev *indio_dev) > > +{ > > + struct ad7768_state *st = iio_priv(indio_dev); > > + int readval, ret; > > + > > + reinit_completion(&st->completion); > > + > > + ret = ad7768_set_mode(st, AD7768_ONE_SHOT); > > + if (ret < 0) > > + return ret; > > + > > + ret = wait_for_completion_timeout(&st->completion, > > + msecs_to_jiffies(1000)); > > + if (!ret) > > + return -ETIMEDOUT; > > + > > + readval = ad7768_spi_reg_read(st, AD7768_REG_ADC_DATA, 3); > > + if (readval < 0) > > + return readval; > > + /* > > + * Any SPI configuration of the AD7768-1 can only be > > + * performed in continuous conversion mode. > > + */ > > + ret = ad7768_set_mode(st, AD7768_CONTINUOUS); > > + if (ret < 0) > > + return ret; > > + > > + return readval; > > +} > > + > > +static int ad7768_reg_access(struct iio_dev *indio_dev, > > + unsigned int reg, > > + unsigned int writeval, > > + unsigned int *readval) > > +{ > > + struct ad7768_state *st = iio_priv(indio_dev); > > + int ret; > > + > > + mutex_lock(&st->lock); > > + if (readval) { > > + ret = ad7768_spi_reg_read(st, reg, 1); > > + if (ret < 0) > > + goto err_unlock; > > + *readval = ret; > > + ret = 0; > > + } else { > > + ret = ad7768_spi_reg_write(st, reg, writeval); > > + } > > +err_unlock: > > + mutex_unlock(&st->lock); > > + > > + return ret; > > +} > > + > > +static int ad7768_read_raw(struct iio_dev *indio_dev, > > + struct iio_chan_spec const *chan, > > + int *val, int *val2, long info) > > +{ > > + struct ad7768_state *st = iio_priv(indio_dev); > > + int scale_uv, ret; > > + > > + switch (info) { > > + case IIO_CHAN_INFO_RAW: > > + ret = iio_device_claim_direct_mode(indio_dev); > > + if (ret) > > + return ret; > > + > > + ret = ad7768_scan_direct(indio_dev); > > + if (ret >= 0) > > + *val = ret; > > + > > + iio_device_release_direct_mode(indio_dev); > > + if (ret < 0) > > + return ret; > > + > > + return IIO_VAL_INT; > > + > > + case IIO_CHAN_INFO_SCALE: > > + scale_uv = regulator_get_voltage(st->vref); > > + if (scale_uv < 0) > > + return scale_uv; > > + > > + *val = (scale_uv * 2) / 1000; > > + *val2 = chan->scan_type.realbits; > > + > > + return IIO_VAL_FRACTIONAL_LOG2; > > + } > > + > > + return -EINVAL; > > +} > > + > > +static const struct iio_info ad7768_info = { > > + .read_raw = &ad7768_read_raw, > > + .debugfs_reg_access = &ad7768_reg_access, > > +}; > > + > > +static int ad7768_setup(struct ad7768_state *st) > > +{ > > + int ret; > > + > > + /* > > + * Two writes to the SPI_RESET[1:0] bits are required to initiate > > + * a software reset. The bits must first be set to 11, and then > > + * to 10. When the sequence is detected, the reset occurs. > > + * See the datasheet, page 70. > > + */ > > + ret = ad7768_spi_reg_write(st, AD7768_REG_SYNC_RESET, 0x3); > > + if (ret) > > + return ret; > > + > > + ret = ad7768_spi_reg_write(st, AD7768_REG_SYNC_RESET, 0x2); > > + if (ret) > > + return ret; > > + > > + /* Set power mode to fast */ > > + return ad7768_spi_reg_write(st, AD7768_REG_POWER_CLOCK, > > + AD7768_FAST_MODE); > > +} > > + > > +static irqreturn_t ad7768_trigger_handler(int irq, void *p) > > +{ > > + struct iio_poll_func *pf = p; > > + struct iio_dev *indio_dev = pf->indio_dev; > > + struct ad7768_state *st = iio_priv(indio_dev); > > + int ret; > > + > > + mutex_lock(&st->lock); > > + > > + ret = spi_read(st->spi, &st->data.d32, 3); > > + if (ret < 0) > > + goto err_unlock; > > + > > + iio_push_to_buffers_with_timestamp(indio_dev, &st->data.d32, > > + iio_get_time_ns(indio_dev)); > > + > > + iio_trigger_notify_done(indio_dev->trig); > > +err_unlock: > > + mutex_unlock(&st->lock); > > + > > + return IRQ_HANDLED; > > +} > > + > > +static irqreturn_t ad7768_interrupt(int irq, void *dev_id) > > +{ > > + struct iio_dev *indio_dev = dev_id; > > + struct ad7768_state *st = iio_priv(indio_dev); > > + > > + if (iio_buffer_enabled(indio_dev)) > > + iio_trigger_poll(st->trig); > > + else > > + complete(&st->completion); > > + > > + return IRQ_HANDLED; > > +}; > > + > > +static int ad7768_buffer_postenable(struct iio_dev *indio_dev) > > +{ > > + struct ad7768_state *st = iio_priv(indio_dev); > > + > > + iio_triggered_buffer_postenable(indio_dev); > > + /* > > + * Write a 1 to the LSB of the INTERFACE_FORMAT register to enter > > + * continuous read mode. Subsequent data reads do not require an > > + * initial 8-bit write to query the ADC_DATA register. > > + */ > > + return ad7768_spi_reg_write(st, AD7768_REG_INTERFACE_FORMAT, > > 0x01); > > +} > > + > > +static int ad7768_buffer_predisable(struct iio_dev *indio_dev) > > +{ > > + struct ad7768_state *st = iio_priv(indio_dev); > > + int ret; > > + > > + /* > > + * To exit continuous read mode, perform a single read of the > > ADC_DATA > > + * reg (0x2C), which allows further configuration of the device. > > + */ > > + ret = ad7768_spi_reg_read(st, AD7768_REG_ADC_DATA, 3); > > + if (ret < 0) > > + return ret; > > + > > + return iio_triggered_buffer_predisable(indio_dev); > > +} > > + > > +static const struct iio_buffer_setup_ops ad7768_buffer_ops = { > > + .postenable = &ad7768_buffer_postenable, > > + .predisable = &ad7768_buffer_predisable, > > +}; > > + > > +static const struct iio_trigger_ops ad7768_trigger_ops = { > > + .validate_device = iio_trigger_validate_own_device, > > +}; > > + > > +static void ad7768_regulator_disable(void *data) > > +{ > > + struct ad7768_state *st = data; > > + > > + regulator_disable(st->vref); > > +} > > + > > +static int ad7768_probe(struct spi_device *spi) > > +{ > > + struct ad7768_state *st; > > + struct iio_dev *indio_dev; > > + int ret; > > + > > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); > > + if (!indio_dev) > > + return -ENOMEM; > > + > > + st = iio_priv(indio_dev); > > + st->spi = spi; > > + > > + st->vref = devm_regulator_get(&spi->dev, "vref"); > > + if (IS_ERR(st->vref)) > > + return PTR_ERR(st->vref); > > + > > + ret = regulator_enable(st->vref); > > + if (ret) { > > + dev_err(&spi->dev, "Failed to enable specified vref > > supply\n"); > > + return ret; > > + } > > + > > + ret = devm_add_action_or_reset(&spi->dev, > > ad7768_regulator_disable, st); > > + if (ret) > > + return ret; > > + > > + spi_set_drvdata(spi, indio_dev); > > + mutex_init(&st->lock); > > + > > + indio_dev->channels = ad7768_channels; > > + indio_dev->num_channels = ARRAY_SIZE(ad7768_channels); > > + indio_dev->dev.parent = &spi->dev; > > + indio_dev->name = spi_get_device_id(spi)->name; > > + indio_dev->info = &ad7768_info; > > + indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED; > > + > > + ret = ad7768_setup(st); > > + if (ret < 0) { > > + dev_err(&spi->dev, "AD7768 setup failed\n"); > > + return ret; > > + } > > + > > + st->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d", > > + indio_dev->name, indio_dev- > > >id); > > + if (!st->trig) > > + return -ENOMEM; > > + > > + st->trig->ops = &ad7768_trigger_ops; > > + st->trig->dev.parent = &spi->dev; > > + iio_trigger_set_drvdata(st->trig, indio_dev); > > + ret = devm_iio_trigger_register(&spi->dev, st->trig); > > + if (ret) > > + return ret; > > + > > + indio_dev->trig = iio_trigger_get(st->trig); > > + > > + init_completion(&st->completion); > > + > > + ret = devm_request_irq(&spi->dev, spi->irq, > > + &ad7768_interrupt, > > + IRQF_TRIGGER_RISING | IRQF_ONESHOT, > > + indio_dev->name, indio_dev); > > + if (ret) > > + return ret; > > + > > + ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, > > + &iio_pollfunc_store_time, > > + &ad7768_trigger_handler, > > + &ad7768_buffer_ops); > > + if (ret) > > + return ret; > > + > > + return devm_iio_device_register(&spi->dev, indio_dev); > > +} > > + > > +static const struct spi_device_id ad7768_id_table[] = { > > + { "ad7768-1", 0 }, > > + {} > > +}; > > +MODULE_DEVICE_TABLE(spi, ad7768_id_table); > > + > > +static const struct of_device_id ad7768_of_match[] = { > > + { .compatible = "adi,ad7768-1" }, > > + { }, > > +}; > > +MODULE_DEVICE_TABLE(of, ad7768_of_match); > > + > > +static struct spi_driver ad7768_driver = { > > + .driver = { > > + .name = "ad7768-1", > > + .of_match_table = ad7768_of_match, > > + }, > > + .probe = ad7768_probe, > > + .id_table = ad7768_id_table, > > +}; > > +module_spi_driver(ad7768_driver); > > + > > +MODULE_AUTHOR("Stefan Popa <stefan.popa@xxxxxxxxxx>"); > > +MODULE_DESCRIPTION("Analog Devices AD7768-1 ADC driver"); > > +MODULE_LICENSE("GPL"); > Mixed license. This is GPL v2 or later according to module.h. >
