Message-ID: <20181210213410.738af156@archlinux>
Date:   Mon, 10 Dec 2018 21:34:10 +0000
From:   Jonathan Cameron <jic23@...nel.org>
To:     Stefan Popa <stefan.popa@...log.com>
Cc:     <Michael.Hennerich@...log.com>, <knaack.h@....de>,
        <lars@...afoo.de>, <pmeerw@...erw.net>,
        <gregkh@...uxfoundation.org>, <linux-kernel@...r.kernel.org>,
        <linux-iio@...r.kernel.org>, <devel@...verdev.osuosl.org>
Subject: Re: [PATCH v4 1/2] staging: iio: ad7606: Move out of staging

On Mon, 10 Dec 2018 13:03:33 +0200
Stefan Popa <stefan.popa@...log.com> wrote:

> Move ad7606 ADC driver out of staging and into the mainline.
> 
> Signed-off-by: Stefan Popa <stefan.popa@...log.com>

Looks good to me.  I'll let it sit for a few days though to give
time for a final review from anyone else who wants to and for
Rob to take a final look at the bindings if he wants to.

Thanks,

Jonathan

> ---
> Changes in v2:
> 	- Simplified the Kconfig menu.
> 	- Added SPDX-License-Identifier.
> 	- Ordered the includes alphabetically.
> 	- Used a threaded interrupt.
> 	- Replaced ad7606_poll_bh_to_ring() with ad7606_trigger_handler().
> 	- Used a trigger. 
> 	- Replaced wait_event_interruptible() with wait_for_completion_timeout().
> 	- Replaced wake_up_interruptible() with complete().
> 	- Used devm_iio_triggered_buffer_setup().
> 	- Added buffer_ops.
> 	- Used single line comments where needed.
> 	- Removed the gap between docs and struct.
> 	- Added ad7606_of_match[].
> Changes in v3:
> 	- Added a comment which offers more information of the way the interrupt
> 	  is triggered.
> 	- Fixed the way a new conversion is triggered.
> 	- endianness = IIO_CPU
> 	- Removed unnecessary mutex locks.
> 	- Removed the buffer_postdisable ops and replaced it with buffer_predisable.
> 	- Added a devm_add_action_or_reset() which deals with regulator_disable().
> 	- Misc style fixes.
> Changes in v4:
> 	- Removed unused fields from the ad7606_state struct.
> 	- Used the find_closest() macro when searching for the available scale
> 	and the oversampling ratios.
> 
>  MAINTAINERS                          |   7 +
>  drivers/iio/adc/Kconfig              |  28 ++
>  drivers/iio/adc/Makefile             |   3 +
>  drivers/iio/adc/ad7606.c             | 588 +++++++++++++++++++++++++++++++++++
>  drivers/iio/adc/ad7606.h             |  99 ++++++
>  drivers/iio/adc/ad7606_par.c         | 105 +++++++
>  drivers/iio/adc/ad7606_spi.c         |  82 +++++
>  drivers/staging/iio/adc/Kconfig      |  34 --
>  drivers/staging/iio/adc/Makefile     |   3 -
>  drivers/staging/iio/adc/ad7606.c     | 565 ---------------------------------
>  drivers/staging/iio/adc/ad7606.h     | 106 -------
>  drivers/staging/iio/adc/ad7606_par.c | 113 -------
>  drivers/staging/iio/adc/ad7606_spi.c |  79 -----
>  13 files changed, 912 insertions(+), 900 deletions(-)
>  create mode 100644 drivers/iio/adc/ad7606.c
>  create mode 100644 drivers/iio/adc/ad7606.h
>  create mode 100644 drivers/iio/adc/ad7606_par.c
>  create mode 100644 drivers/iio/adc/ad7606_spi.c
>  delete mode 100644 drivers/staging/iio/adc/ad7606.c
>  delete mode 100644 drivers/staging/iio/adc/ad7606.h
>  delete mode 100644 drivers/staging/iio/adc/ad7606_par.c
>  delete mode 100644 drivers/staging/iio/adc/ad7606_spi.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index f642044..843545d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -839,6 +839,13 @@ S:	Supported
>  F:	drivers/iio/dac/ad5758.c
>  F:	Documentation/devicetree/bindings/iio/dac/ad5758.txt
>  
> +ANALOG DEVICES INC AD7606 DRIVER
> +M:	Stefan Popa <stefan.popa@...log.com>
> +L:	linux-iio@...r.kernel.org
> +W:	http://ez.analog.com/community/linux-device-drivers
> +S:	Supported
> +F:	drivers/iio/adc/ad7606.c
> +
>  ANALOG DEVICES INC AD9389B DRIVER
>  M:	Hans Verkuil <hans.verkuil@...co.com>
>  L:	linux-media@...r.kernel.org
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index a52fea8..c3f61c9 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -58,6 +58,34 @@ config AD7476
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called ad7476.
>  
> +config AD7606
> +	tristate
> +	depends on GPIOLIB || COMPILE_TEST
> +	depends on HAS_IOMEM
> +	select IIO_BUFFER
> +	select IIO_TRIGGERED_BUFFER
> +
> +config AD7606_IFACE_PARALLEL
> +	tristate "Analog Devices AD7606 ADC driver with parallel interface support"
> +	select AD7606
> +	help
> +	  Say yes here to build parallel interface support for Analog Devices:
> +	  ad7605-4, ad7606, ad7606-6, ad7606-4 analog to digital converters (ADC).
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called ad7606_parallel.
> +
> +config AD7606_IFACE_SPI
> +	tristate "Analog Devices AD7606 ADC driver with spi interface support"
> +	depends on SPI
> +	select AD7606
> +	help
> +	  Say yes here to build spi interface support for Analog Devices:
> +	  ad7605-4, ad7606, ad7606-6, ad7606-4 analog to digital converters (ADC).
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called ad7606_spi.
> +
>  config AD7766
>  	tristate "Analog Devices AD7766/AD7767 ADC driver"
>  	depends on SPI_MASTER
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> index a6e6a0b..b734f4f 100644
> --- a/drivers/iio/adc/Makefile
> +++ b/drivers/iio/adc/Makefile
> @@ -8,6 +8,9 @@ obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
>  obj-$(CONFIG_AD7266) += ad7266.o
>  obj-$(CONFIG_AD7291) += ad7291.o
>  obj-$(CONFIG_AD7298) += ad7298.o
> +obj-$(CONFIG_AD7606_IFACE_PARALLEL) += ad7606_par.o
> +obj-$(CONFIG_AD7606_IFACE_SPI) += ad7606_spi.o
> +obj-$(CONFIG_AD7606) += ad7606.o
>  obj-$(CONFIG_AD7923) += ad7923.o
>  obj-$(CONFIG_AD7476) += ad7476.o
>  obj-$(CONFIG_AD7766) += ad7766.o
> diff --git a/drivers/iio/adc/ad7606.c b/drivers/iio/adc/ad7606.c
> new file mode 100644
> index 0000000..fa3c8e0
> --- /dev/null
> +++ b/drivers/iio/adc/ad7606.c
> @@ -0,0 +1,588 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * AD7606 SPI ADC driver
> + *
> + * Copyright 2011 Analog Devices Inc.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/sched.h>
> +#include <linux/slab.h>
> +#include <linux/sysfs.h>
> +#include <linux/util_macros.h>
> +
> +#include <linux/iio/iio.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/triggered_buffer.h>
> +#include <linux/iio/trigger_consumer.h>
> +
> +#include "ad7606.h"
> +
> +/*
> + * Scales are computed as 5000/32768 and 10000/32768 respectively,
> + * so that when applied to the raw values they provide mV values
> + */
> +static const unsigned int scale_avail[2] = {
> +	152588, 305176
> +};
> +
> +static const unsigned int ad7606_oversampling_avail[7] = {
> +	1, 2, 4, 8, 16, 32, 64,
> +};
> +
> +static int ad7606_reset(struct ad7606_state *st)
> +{
> +	if (st->gpio_reset) {
> +		gpiod_set_value(st->gpio_reset, 1);
> +		ndelay(100); /* t_reset >= 100ns */
> +		gpiod_set_value(st->gpio_reset, 0);
> +		return 0;
> +	}
> +
> +	return -ENODEV;
> +}
> +
> +static int ad7606_read_samples(struct ad7606_state *st)
> +{
> +	unsigned int num = st->chip_info->num_channels;
> +	u16 *data = st->data;
> +	int ret;
> +
> +	/*
> +	 * The frstdata signal is set to high while and after reading the sample
> +	 * of the first channel and low for all other channels. This can be used
> +	 * to check that the incoming data is correctly aligned. During normal
> +	 * operation the data should never become unaligned, but some glitch or
> +	 * electrostatic discharge might cause an extra read or clock cycle.
> +	 * Monitoring the frstdata signal allows to recover from such failure
> +	 * situations.
> +	 */
> +
> +	if (st->gpio_frstdata) {
> +		ret = st->bops->read_block(st->dev, 1, data);
> +		if (ret)
> +			return ret;
> +
> +		if (!gpiod_get_value(st->gpio_frstdata)) {
> +			ad7606_reset(st);
> +			return -EIO;
> +		}
> +
> +		data++;
> +		num--;
> +	}
> +
> +	return st->bops->read_block(st->dev, num, data);
> +}
> +
> +static irqreturn_t ad7606_trigger_handler(int irq, void *p)
> +{
> +	struct iio_poll_func *pf = p;
> +	struct iio_dev *indio_dev = pf->indio_dev;
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +	int ret;
> +
> +	mutex_lock(&st->lock);
> +
> +	ret = ad7606_read_samples(st);
> +	if (ret == 0)
> +		iio_push_to_buffers_with_timestamp(indio_dev, st->data,
> +						   iio_get_time_ns(indio_dev));
> +
> +	iio_trigger_notify_done(indio_dev->trig);
> +	/* The rising edge of the CONVST signal starts a new conversion. */
> +	gpiod_set_value(st->gpio_convst, 1);
> +
> +	mutex_unlock(&st->lock);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned int ch)
> +{
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +	int ret;
> +
> +	gpiod_set_value(st->gpio_convst, 1);
> +	ret = wait_for_completion_timeout(&st->completion,
> +					  msecs_to_jiffies(1000));
> +	if (!ret) {
> +		ret = -ETIMEDOUT;
> +		goto error_ret;
> +	}
> +
> +	ret = ad7606_read_samples(st);
> +	if (ret == 0)
> +		ret = st->data[ch];
> +
> +error_ret:
> +	gpiod_set_value(st->gpio_convst, 0);
> +
> +	return ret;
> +}
> +
> +static int ad7606_read_raw(struct iio_dev *indio_dev,
> +			   struct iio_chan_spec const *chan,
> +			   int *val,
> +			   int *val2,
> +			   long m)
> +{
> +	int ret;
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +
> +	switch (m) {
> +	case IIO_CHAN_INFO_RAW:
> +		ret = iio_device_claim_direct_mode(indio_dev);
> +		if (ret)
> +			return ret;
> +
> +		ret = ad7606_scan_direct(indio_dev, chan->address);
> +		iio_device_release_direct_mode(indio_dev);
> +
> +		if (ret < 0)
> +			return ret;
> +		*val = (short)ret;
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_SCALE:
> +		*val = 0;
> +		*val2 = scale_avail[st->range];
> +		return IIO_VAL_INT_PLUS_MICRO;
> +	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
> +		*val = st->oversampling;
> +		return IIO_VAL_INT;
> +	}
> +	return -EINVAL;
> +}
> +
> +static ssize_t in_voltage_scale_available_show(struct device *dev,
> +					       struct device_attribute *attr,
> +					       char *buf)
> +{
> +	int i, len = 0;
> +
> +	for (i = 0; i < ARRAY_SIZE(scale_avail); i++)
> +		len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06u ",
> +				 scale_avail[i]);
> +
> +	buf[len - 1] = '\n';
> +
> +	return len;
> +}
> +
> +static IIO_DEVICE_ATTR_RO(in_voltage_scale_available, 0);
> +
> +static int ad7606_write_raw(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan,
> +			    int val,
> +			    int val2,
> +			    long mask)
> +{
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +	int values[3], i;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_SCALE:
> +		mutex_lock(&st->lock);
> +		i = find_closest(val2, scale_avail, ARRAY_SIZE(scale_avail));
> +		gpiod_set_value(st->gpio_range, i);
> +		st->range = i;
> +		mutex_unlock(&st->lock);
> +
> +		return 0;
> +	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
> +		if (val2)
> +			return -EINVAL;
> +		i = find_closest(val, ad7606_oversampling_avail,
> +				 ARRAY_SIZE(ad7606_oversampling_avail));
> +
> +		values[0] = (i >> 0) & 1;
> +		values[1] = (i >> 1) & 1;
> +		values[2] = (i >> 2) & 1;
> +
> +		mutex_lock(&st->lock);
> +		gpiod_set_array_value(ARRAY_SIZE(values), st->gpio_os->desc,
> +				      values);
> +		st->oversampling = ad7606_oversampling_avail[i];
> +		mutex_unlock(&st->lock);
> +
> +		return 0;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static IIO_CONST_ATTR(oversampling_ratio_available, "1 2 4 8 16 32 64");
> +
> +static struct attribute *ad7606_attributes_os_and_range[] = {
> +	&iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
> +	&iio_const_attr_oversampling_ratio_available.dev_attr.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group ad7606_attribute_group_os_and_range = {
> +	.attrs = ad7606_attributes_os_and_range,
> +};
> +
> +static struct attribute *ad7606_attributes_os[] = {
> +	&iio_const_attr_oversampling_ratio_available.dev_attr.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group ad7606_attribute_group_os = {
> +	.attrs = ad7606_attributes_os,
> +};
> +
> +static struct attribute *ad7606_attributes_range[] = {
> +	&iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group ad7606_attribute_group_range = {
> +	.attrs = ad7606_attributes_range,
> +};
> +
> +#define AD760X_CHANNEL(num, mask) {				\
> +		.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),\
> +		.info_mask_shared_by_all = mask,		\
> +		.scan_index = num,				\
> +		.scan_type = {					\
> +			.sign = 's',				\
> +			.realbits = 16,				\
> +			.storagebits = 16,			\
> +			.endianness = IIO_CPU,			\
> +		},						\
> +}
> +
> +#define AD7605_CHANNEL(num)	\
> +	AD760X_CHANNEL(num, 0)
> +
> +#define AD7606_CHANNEL(num)	\
> +	AD760X_CHANNEL(num, BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO))
> +
> +static const struct iio_chan_spec ad7605_channels[] = {
> +	IIO_CHAN_SOFT_TIMESTAMP(4),
> +	AD7605_CHANNEL(0),
> +	AD7605_CHANNEL(1),
> +	AD7605_CHANNEL(2),
> +	AD7605_CHANNEL(3),
> +};
> +
> +static const struct iio_chan_spec ad7606_channels[] = {
> +	IIO_CHAN_SOFT_TIMESTAMP(8),
> +	AD7606_CHANNEL(0),
> +	AD7606_CHANNEL(1),
> +	AD7606_CHANNEL(2),
> +	AD7606_CHANNEL(3),
> +	AD7606_CHANNEL(4),
> +	AD7606_CHANNEL(5),
> +	AD7606_CHANNEL(6),
> +	AD7606_CHANNEL(7),
> +};
> +
> +static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
> +	/* More devices added in future */
> +	[ID_AD7605_4] = {
> +		.channels = ad7605_channels,
> +		.num_channels = 5,
> +	},
> +	[ID_AD7606_8] = {
> +		.channels = ad7606_channels,
> +		.num_channels = 9,
> +		.has_oversampling = true,
> +	},
> +	[ID_AD7606_6] = {
> +		.channels = ad7606_channels,
> +		.num_channels = 7,
> +		.has_oversampling = true,
> +	},
> +	[ID_AD7606_4] = {
> +		.channels = ad7606_channels,
> +		.num_channels = 5,
> +		.has_oversampling = true,
> +	},
> +};
> +
> +static int ad7606_request_gpios(struct ad7606_state *st)
> +{
> +	struct device *dev = st->dev;
> +
> +	st->gpio_convst = devm_gpiod_get(dev, "adi,conversion-start",
> +					 GPIOD_OUT_LOW);
> +	if (IS_ERR(st->gpio_convst))
> +		return PTR_ERR(st->gpio_convst);
> +
> +	st->gpio_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
> +	if (IS_ERR(st->gpio_reset))
> +		return PTR_ERR(st->gpio_reset);
> +
> +	st->gpio_range = devm_gpiod_get_optional(dev, "adi,range",
> +						 GPIOD_OUT_LOW);
> +	if (IS_ERR(st->gpio_range))
> +		return PTR_ERR(st->gpio_range);
> +
> +	st->gpio_standby = devm_gpiod_get_optional(dev, "standby",
> +						   GPIOD_OUT_HIGH);
> +	if (IS_ERR(st->gpio_standby))
> +		return PTR_ERR(st->gpio_standby);
> +
> +	st->gpio_frstdata = devm_gpiod_get_optional(dev, "adi,first-data",
> +						    GPIOD_IN);
> +	if (IS_ERR(st->gpio_frstdata))
> +		return PTR_ERR(st->gpio_frstdata);
> +
> +	if (!st->chip_info->has_oversampling)
> +		return 0;
> +
> +	st->gpio_os = devm_gpiod_get_array_optional(dev,
> +						    "adi,oversampling-ratio",
> +						    GPIOD_OUT_LOW);
> +	return PTR_ERR_OR_ZERO(st->gpio_os);
> +}
> +
> +/*
> + * The BUSY signal indicates when conversions are in progress, so when a rising
> + * edge of CONVST is applied, BUSY goes logic high and transitions low at the
> + * end of the entire conversion process. The falling edge of the BUSY signal
> + * triggers this interrupt.
> + */
> +static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
> +{
> +	struct iio_dev *indio_dev = dev_id;
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +
> +	if (iio_buffer_enabled(indio_dev)) {
> +		gpiod_set_value(st->gpio_convst, 0);
> +		iio_trigger_poll_chained(st->trig);
> +	} else {
> +		complete(&st->completion);
> +	}
> +
> +	return IRQ_HANDLED;
> +};
> +
> +static int ad7606_validate_trigger(struct iio_dev *indio_dev,
> +				   struct iio_trigger *trig)
> +{
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +
> +	if (st->trig != trig)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
> +static int ad7606_buffer_postenable(struct iio_dev *indio_dev)
> +{
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +
> +	iio_triggered_buffer_postenable(indio_dev);
> +	gpiod_set_value(st->gpio_convst, 1);
> +
> +	return 0;
> +}
> +
> +static int ad7606_buffer_predisable(struct iio_dev *indio_dev)
> +{
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +	int ret;
> +
> +	reinit_completion(&st->completion);
> +	gpiod_set_value(st->gpio_convst, 1);
> +	ret = wait_for_completion_timeout(&st->completion,
> +					  msecs_to_jiffies(1000));
> +	gpiod_set_value(st->gpio_convst, 0);
> +
> +	return iio_triggered_buffer_predisable(indio_dev);
> +}
> +
> +static const struct iio_buffer_setup_ops ad7606_buffer_ops = {
> +	.postenable = &ad7606_buffer_postenable,
> +	.predisable = &ad7606_buffer_predisable,
> +};
> +
> +static const struct iio_info ad7606_info_no_os_or_range = {
> +	.read_raw = &ad7606_read_raw,
> +	.validate_trigger = &ad7606_validate_trigger,
> +};
> +
> +static const struct iio_info ad7606_info_os_and_range = {
> +	.read_raw = &ad7606_read_raw,
> +	.write_raw = &ad7606_write_raw,
> +	.attrs = &ad7606_attribute_group_os_and_range,
> +	.validate_trigger = &ad7606_validate_trigger,
> +};
> +
> +static const struct iio_info ad7606_info_os = {
> +	.read_raw = &ad7606_read_raw,
> +	.write_raw = &ad7606_write_raw,
> +	.attrs = &ad7606_attribute_group_os,
> +	.validate_trigger = &ad7606_validate_trigger,
> +};
> +
> +static const struct iio_info ad7606_info_range = {
> +	.read_raw = &ad7606_read_raw,
> +	.write_raw = &ad7606_write_raw,
> +	.attrs = &ad7606_attribute_group_range,
> +	.validate_trigger = &ad7606_validate_trigger,
> +};
> +
> +static const struct iio_trigger_ops ad7606_trigger_ops = {
> +	.validate_device = iio_trigger_validate_own_device,
> +};
> +
> +static void ad7606_regulator_disable(void *data)
> +{
> +	struct ad7606_state *st = data;
> +
> +	regulator_disable(st->reg);
> +}
> +
> +int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
> +		 const char *name, unsigned int id,
> +		 const struct ad7606_bus_ops *bops)
> +{
> +	struct ad7606_state *st;
> +	int ret;
> +	struct iio_dev *indio_dev;
> +
> +	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	st = iio_priv(indio_dev);
> +	dev_set_drvdata(dev, indio_dev);
> +
> +	st->dev = dev;
> +	mutex_init(&st->lock);
> +	st->bops = bops;
> +	st->base_address = base_address;
> +	st->oversampling = 1;
> +
> +	st->reg = devm_regulator_get(dev, "avcc");
> +	if (IS_ERR(st->reg))
> +		return PTR_ERR(st->reg);
> +
> +	ret = regulator_enable(st->reg);
> +	if (ret) {
> +		dev_err(dev, "Failed to enable specified AVcc supply\n");
> +		return ret;
> +	}
> +
> +	ret = devm_add_action_or_reset(dev, ad7606_regulator_disable, st);
> +	if (ret)
> +		return ret;
> +
> +	st->chip_info = &ad7606_chip_info_tbl[id];
> +
> +	ret = ad7606_request_gpios(st);
> +	if (ret)
> +		return ret;
> +
> +	indio_dev->dev.parent = dev;
> +	if (st->gpio_os) {
> +		if (st->gpio_range)
> +			indio_dev->info = &ad7606_info_os_and_range;
> +		else
> +			indio_dev->info = &ad7606_info_os;
> +	} else {
> +		if (st->gpio_range)
> +			indio_dev->info = &ad7606_info_range;
> +		else
> +			indio_dev->info = &ad7606_info_no_os_or_range;
> +	}
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->name = name;
> +	indio_dev->channels = st->chip_info->channels;
> +	indio_dev->num_channels = st->chip_info->num_channels;
> +
> +	ret = ad7606_reset(st);
> +	if (ret)
> +		dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
> +
> +	st->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
> +					  indio_dev->name, indio_dev->id);
> +	if (st->trig == NULL)
> +		return -ENOMEM;
> +
> +	st->trig->ops = &ad7606_trigger_ops;
> +	st->trig->dev.parent = dev;
> +	iio_trigger_set_drvdata(st->trig, indio_dev);
> +	ret = devm_iio_trigger_register(dev, st->trig);
> +	if (ret)
> +		return ret;
> +
> +	indio_dev->trig = iio_trigger_get(st->trig);
> +
> +	init_completion(&st->completion);
> +
> +	ret = devm_request_threaded_irq(dev, irq,
> +					NULL,
> +					&ad7606_interrupt,
> +					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> +					name, indio_dev);
> +	if (ret)
> +		return ret;
> +
> +	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
> +					      &iio_pollfunc_store_time,
> +					      &ad7606_trigger_handler,
> +					      &ad7606_buffer_ops);
> +	if (ret)
> +		return ret;
> +
> +	return devm_iio_device_register(dev, indio_dev);
> +

Real nitpick.  No point in blank line here.  I'll probably take the view
this is so trivial I'll just fix it when applying (or forget about it).

> +}
> +EXPORT_SYMBOL_GPL(ad7606_probe);
> +
> +#ifdef CONFIG_PM_SLEEP
> +
> +static int ad7606_suspend(struct device *dev)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +
> +	if (st->gpio_standby) {
> +		gpiod_set_value(st->gpio_range, 1);
> +		gpiod_set_value(st->gpio_standby, 0);
> +	}
> +
> +	return 0;
> +}
> +
> +static int ad7606_resume(struct device *dev)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +
> +	if (st->gpio_standby) {
> +		gpiod_set_value(st->gpio_range, st->range);
> +		gpiod_set_value(st->gpio_standby, 1);
> +		ad7606_reset(st);
> +	}
> +
> +	return 0;
> +}
> +
> +SIMPLE_DEV_PM_OPS(ad7606_pm_ops, ad7606_suspend, ad7606_resume);
> +EXPORT_SYMBOL_GPL(ad7606_pm_ops);
> +
> +#endif
> +
> +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@...log.com>");
> +MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/iio/adc/ad7606.h b/drivers/iio/adc/ad7606.h
> new file mode 100644
> index 0000000..40433af
> --- /dev/null
> +++ b/drivers/iio/adc/ad7606.h
> @@ -0,0 +1,99 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * AD7606 ADC driver
> + *
> + * Copyright 2011 Analog Devices Inc.
> + */
> +
> +#ifndef IIO_ADC_AD7606_H_
> +#define IIO_ADC_AD7606_H_
> +
> +/**
> + * struct ad7606_chip_info - chip specific information
> + * @channels:		channel specification
> + * @num_channels:	number of channels
> + * @has_oversampling:   whether the device has oversampling support
> + */
> +struct ad7606_chip_info {
> +	const struct iio_chan_spec	*channels;
> +	unsigned int			num_channels;
> +	bool				has_oversampling;
> +};
> +
> +/**
> + * struct ad7606_state - driver instance specific data
> + * @dev		pointer to kernel device
> + * @chip_info		entry in the table of chips that describes this device
> + * @reg		regulator info for the the power supply of the device
> + * @bops		bus operations (SPI or parallel)
> + * @range		voltage range selection, selects which scale to apply
> + * @oversampling	oversampling selection
> + * @base_address	address from where to read data in parallel operation
> + * @lock		protect sensor state from concurrent accesses to GPIOs
> + * @gpio_convst	GPIO descriptor for conversion start signal (CONVST)
> + * @gpio_reset		GPIO descriptor for device hard-reset
> + * @gpio_range		GPIO descriptor for range selection
> + * @gpio_standby	GPIO descriptor for stand-by signal (STBY),
> + *			controls power-down mode of device
> + * @gpio_frstdata	GPIO descriptor for reading from device when data
> + *			is being read on the first channel
> + * @gpio_os		GPIO descriptors to control oversampling on the device
> + * @complete		completion to indicate end of conversion
> + * @trig		The IIO trigger associated with the device.
> + * @data		buffer for reading data from the device
> + */
> +struct ad7606_state {
> +	struct device			*dev;
> +	const struct ad7606_chip_info	*chip_info;
> +	struct regulator		*reg;
> +	const struct ad7606_bus_ops	*bops;
> +	unsigned int			range;
> +	unsigned int			oversampling;
> +	void __iomem			*base_address;
> +
> +	struct mutex			lock; /* protect sensor state */
> +	struct gpio_desc		*gpio_convst;
> +	struct gpio_desc		*gpio_reset;
> +	struct gpio_desc		*gpio_range;
> +	struct gpio_desc		*gpio_standby;
> +	struct gpio_desc		*gpio_frstdata;
> +	struct gpio_descs		*gpio_os;
> +	struct iio_trigger		*trig;
> +	struct completion		completion;
> +
> +	/*
> +	 * DMA (thus cache coherency maintenance) requires the
> +	 * transfer buffers to live in their own cache lines.
> +	 * 8 * 16-bit samples + 64-bit timestamp
> +	 */
> +	unsigned short			data[12] ____cacheline_aligned;
> +};
> +
> +/**
> + * struct ad7606_bus_ops - driver bus operations
> + * @read_block		function pointer for reading blocks of data
> + */
> +struct ad7606_bus_ops {
> +	/* more methods added in future? */
> +	int (*read_block)(struct device *dev, int num, void *data);
> +};
> +
> +int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
> +		 const char *name, unsigned int id,
> +		 const struct ad7606_bus_ops *bops);
> +
> +enum ad7606_supported_device_ids {
> +	ID_AD7605_4,
> +	ID_AD7606_8,
> +	ID_AD7606_6,
> +	ID_AD7606_4
> +};
> +
> +#ifdef CONFIG_PM_SLEEP
> +extern const struct dev_pm_ops ad7606_pm_ops;
> +#define AD7606_PM_OPS (&ad7606_pm_ops)
> +#else
> +#define AD7606_PM_OPS NULL
> +#endif
> +
> +#endif /* IIO_ADC_AD7606_H_ */
> diff --git a/drivers/iio/adc/ad7606_par.c b/drivers/iio/adc/ad7606_par.c
> new file mode 100644
> index 0000000..32c7069
> --- /dev/null
> +++ b/drivers/iio/adc/ad7606_par.c
> @@ -0,0 +1,105 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * AD7606 Parallel Interface ADC driver
> + *
> + * Copyright 2011 Analog Devices Inc.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/types.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +
> +#include <linux/iio/iio.h>
> +#include "ad7606.h"
> +
> +static int ad7606_par16_read_block(struct device *dev,
> +				   int count, void *buf)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +
> +	insw((unsigned long)st->base_address, buf, count);
> +
> +	return 0;
> +}
> +
> +static const struct ad7606_bus_ops ad7606_par16_bops = {
> +	.read_block = ad7606_par16_read_block,
> +};
> +
> +static int ad7606_par8_read_block(struct device *dev,
> +				  int count, void *buf)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct ad7606_state *st = iio_priv(indio_dev);
> +
> +	insb((unsigned long)st->base_address, buf, count * 2);
> +
> +	return 0;
> +}
> +
> +static const struct ad7606_bus_ops ad7606_par8_bops = {
> +	.read_block = ad7606_par8_read_block,
> +};
> +
> +static int ad7606_par_probe(struct platform_device *pdev)
> +{
> +	const struct platform_device_id *id = platform_get_device_id(pdev);
> +	struct resource *res;
> +	void __iomem *addr;
> +	resource_size_t remap_size;
> +	int irq;
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0) {
> +		dev_err(&pdev->dev, "no irq: %d\n", irq);
> +		return irq;
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	addr = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(addr))
> +		return PTR_ERR(addr);
> +
> +	remap_size = resource_size(res);
> +
> +	return ad7606_probe(&pdev->dev, irq, addr,
> +			    id->name, id->driver_data,
> +			    remap_size > 1 ? &ad7606_par16_bops :
> +			    &ad7606_par8_bops);
> +}
> +
> +static const struct platform_device_id ad7606_driver_ids[] = {
> +	{ .name	= "ad7605-4", .driver_data = ID_AD7605_4, },
> +	{ .name	= "ad7606-4", .driver_data = ID_AD7606_4, },
> +	{ .name	= "ad7606-6", .driver_data = ID_AD7606_6, },
> +	{ .name	= "ad7606-8", .driver_data = ID_AD7606_8, },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(platform, ad7606_driver_ids);
> +
> +static const struct of_device_id ad7606_of_match[] = {
> +	{ .compatible = "adi,ad7605-4" },
> +	{ .compatible = "adi,ad7606-4" },
> +	{ .compatible = "adi,ad7606-6" },
> +	{ .compatible = "adi,ad7606-8" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, ad7606_of_match);
> +
> +static struct platform_driver ad7606_driver = {
> +	.probe = ad7606_par_probe,
> +	.id_table = ad7606_driver_ids,
> +	.driver = {
> +		.name = "ad7606",
> +		.pm = AD7606_PM_OPS,
> +		.of_match_table = ad7606_of_match,
> +	},
> +};
> +module_platform_driver(ad7606_driver);
> +
> +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@...log.com>");
> +MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/iio/adc/ad7606_spi.c b/drivers/iio/adc/ad7606_spi.c
> new file mode 100644
> index 0000000..6bb1867
> --- /dev/null
> +++ b/drivers/iio/adc/ad7606_spi.c
> @@ -0,0 +1,82 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * AD7606 SPI ADC driver
> + *
> + * Copyright 2011 Analog Devices Inc.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/spi/spi.h>
> +#include <linux/types.h>
> +#include <linux/err.h>
> +
> +#include <linux/iio/iio.h>
> +#include "ad7606.h"
> +
> +#define MAX_SPI_FREQ_HZ		23500000	/* VDRIVE above 4.75 V */
> +
> +static int ad7606_spi_read_block(struct device *dev,
> +				 int count, void *buf)
> +{
> +	struct spi_device *spi = to_spi_device(dev);
> +	int i, ret;
> +	unsigned short *data = buf;
> +	__be16 *bdata = buf;
> +
> +	ret = spi_read(spi, buf, count * 2);
> +	if (ret < 0) {
> +		dev_err(&spi->dev, "SPI read error\n");
> +		return ret;
> +	}
> +
> +	for (i = 0; i < count; i++)
> +		data[i] = be16_to_cpu(bdata[i]);
> +
> +	return 0;
> +}
> +
> +static const struct ad7606_bus_ops ad7606_spi_bops = {
> +	.read_block = ad7606_spi_read_block,
> +};
> +
> +static int ad7606_spi_probe(struct spi_device *spi)
> +{
> +	const struct spi_device_id *id = spi_get_device_id(spi);
> +
> +	return ad7606_probe(&spi->dev, spi->irq, NULL,
> +			    id->name, id->driver_data,
> +			    &ad7606_spi_bops);
> +}
> +
> +static const struct spi_device_id ad7606_id_table[] = {
> +	{ "ad7605-4", ID_AD7605_4 },
> +	{ "ad7606-4", ID_AD7606_4 },
> +	{ "ad7606-6", ID_AD7606_6 },
> +	{ "ad7606-8", ID_AD7606_8 },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(spi, ad7606_id_table);
> +
> +static const struct of_device_id ad7606_of_match[] = {
> +	{ .compatible = "adi,ad7605-4" },
> +	{ .compatible = "adi,ad7606-4" },
> +	{ .compatible = "adi,ad7606-6" },
> +	{ .compatible = "adi,ad7606-8" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, ad7606_of_match);
> +
> +static struct spi_driver ad7606_driver = {
> +	.driver = {
> +		.name = "ad7606",
> +		.of_match_table = ad7606_of_match,
> +		.pm = AD7606_PM_OPS,
> +	},
> +	.probe = ad7606_spi_probe,
> +	.id_table = ad7606_id_table,
> +};
> +module_spi_driver(ad7606_driver);
> +
> +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@...log.com>");
> +MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
> +MODULE_LICENSE("GPL v2");
...

Powered by blists - more mailing lists