Re: [PATCH] staging: iio: Drop ADIS16060 driver from staging

[Jonathan Cameron <jic23@jic23.retrosnub.co.uk>]

On Sun, 20 May 2018 14:45:01 +0100
Jonathan Cameron <Jonathan.Cameron@huawei.com> wrote:

> This part has been declared "not for new designs". It is now
> difficult to obtain and we have had no-one come forward with hardware
> making it difficult to proceed with the necessary work to move this
> driver out of staging.
> 
> The device uses two separate chip selects and would require locking
> between them which is thought to be difficult to enforce without
> non trivial changes in the SPI subsystem.  This work simply isn't worth
> doing given the status of the part and the fact no one seems to have
> gone for a similar hardware design since this one.
> 
> If anyone does have access to one of these and is willing to contribute
> the time necessary then we can reevaluate dropping the driver.
> 
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Applied to the togreg branch of iio.git ready for the merge window
after the one that will probably open later today.

Thanks,

Jonathan

> ---
>  drivers/staging/iio/Kconfig               |   1 -
>  drivers/staging/iio/Makefile              |   1 -
>  drivers/staging/iio/gyro/Kconfig          |  16 --
>  drivers/staging/iio/gyro/Makefile         |   6 -
>  drivers/staging/iio/gyro/adis16060_core.c | 234 ----------------------
>  5 files changed, 258 deletions(-)
> 
> diff --git a/drivers/staging/iio/Kconfig b/drivers/staging/iio/Kconfig
> index aee2335a25a1..e86ac9e47867 100644
> --- a/drivers/staging/iio/Kconfig
> +++ b/drivers/staging/iio/Kconfig
> @@ -9,7 +9,6 @@ source "drivers/staging/iio/adc/Kconfig"
>  source "drivers/staging/iio/addac/Kconfig"
>  source "drivers/staging/iio/cdc/Kconfig"
>  source "drivers/staging/iio/frequency/Kconfig"
> -source "drivers/staging/iio/gyro/Kconfig"
>  source "drivers/staging/iio/impedance-analyzer/Kconfig"
>  source "drivers/staging/iio/meter/Kconfig"
>  source "drivers/staging/iio/resolver/Kconfig"
> diff --git a/drivers/staging/iio/Makefile b/drivers/staging/iio/Makefile
> index c28d657497de..b15904b99581 100644
> --- a/drivers/staging/iio/Makefile
> +++ b/drivers/staging/iio/Makefile
> @@ -8,7 +8,6 @@ obj-y += adc/
>  obj-y += addac/
>  obj-y += cdc/
>  obj-y += frequency/
> -obj-y += gyro/
>  obj-y += impedance-analyzer/
>  obj-y += meter/
>  obj-y += resolver/
> diff --git a/drivers/staging/iio/gyro/Kconfig b/drivers/staging/iio/gyro/Kconfig
> deleted file mode 100644
> index f62f68fd6f3f..000000000000
> --- a/drivers/staging/iio/gyro/Kconfig
> +++ /dev/null
> @@ -1,16 +0,0 @@
> -#
> -# IIO Digital Gyroscope Sensor drivers configuration
> -#
> -menu "Digital gyroscope sensors"
> -
> -config ADIS16060
> -	tristate "Analog Devices ADIS16060 Yaw Rate Gyroscope with SPI driver"
> -	depends on SPI
> -	help
> -	  Say Y (yes) here to build support for Analog Devices adis16060 wide bandwidth
> -	  yaw rate gyroscope with SPI.
> -
> -	  To compile this driver as a module, say M here: the module will be
> -	  called adis16060. If unsure, say N.
> -
> -endmenu
> diff --git a/drivers/staging/iio/gyro/Makefile b/drivers/staging/iio/gyro/Makefile
> deleted file mode 100644
> index cf22d6d55e27..000000000000
> --- a/drivers/staging/iio/gyro/Makefile
> +++ /dev/null
> @@ -1,6 +0,0 @@
> -#
> -# Makefile for digital gyroscope sensor drivers
> -#
> -
> -adis16060-y             := adis16060_core.o
> -obj-$(CONFIG_ADIS16060) += adis16060.o
> diff --git a/drivers/staging/iio/gyro/adis16060_core.c b/drivers/staging/iio/gyro/adis16060_core.c
> deleted file mode 100644
> index 4e7630caf7d3..000000000000
> --- a/drivers/staging/iio/gyro/adis16060_core.c
> +++ /dev/null
> @@ -1,234 +0,0 @@
> -/*
> - * ADIS16060 Wide Bandwidth Yaw Rate Gyroscope with SPI driver
> - *
> - * Copyright 2010 Analog Devices Inc.
> - *
> - * Licensed under the GPL-2 or later.
> - */
> -
> -#include <linux/module.h>
> -#include <linux/delay.h>
> -#include <linux/mutex.h>
> -#include <linux/device.h>
> -#include <linux/kernel.h>
> -#include <linux/spi/spi.h>
> -#include <linux/slab.h>
> -#include <linux/sysfs.h>
> -
> -#include <linux/iio/iio.h>
> -#include <linux/iio/sysfs.h>
> -
> -#define ADIS16060_GYRO		0x20 /* Measure Angular Rate (Gyro) */
> -#define ADIS16060_TEMP_OUT	0x10 /* Measure Temperature */
> -#define ADIS16060_AIN2		0x80 /* Measure AIN2 */
> -#define ADIS16060_AIN1		0x40 /* Measure AIN1 */
> -
> -/**
> - * struct adis16060_state - device instance specific data
> - * @us_w:		actual spi_device to write config
> - * @us_r:		actual spi_device to read back data
> - * @buf:		transmit or receive buffer
> - * @buf_lock:		mutex to protect tx and rx
> - **/
> -struct adis16060_state {
> -	struct spi_device		*us_w;
> -	struct spi_device		*us_r;
> -	struct mutex			buf_lock;
> -
> -	u8 buf[3] ____cacheline_aligned;
> -};
> -
> -static struct iio_dev *adis16060_iio_dev;
> -
> -static int adis16060_spi_write_then_read(struct iio_dev *indio_dev,
> -					 u8 conf, u16 *val)
> -{
> -	int ret;
> -	struct adis16060_state *st = iio_priv(indio_dev);
> -
> -	mutex_lock(&st->buf_lock);
> -	st->buf[2] = conf; /* The last 8 bits clocked in are latched */
> -	ret = spi_write(st->us_w, st->buf, 3);
> -
> -	if (ret < 0) {
> -		mutex_unlock(&st->buf_lock);
> -		return ret;
> -	}
> -
> -	ret = spi_read(st->us_r, st->buf, 3);
> -
> -	/* The internal successive approximation ADC begins the
> -	 * conversion process on the falling edge of MSEL1 and
> -	 * starts to place data MSB first on the DOUT line at
> -	 * the 6th falling edge of SCLK
> -	 */
> -	if (!ret)
> -		*val = ((st->buf[0] & 0x3) << 12) |
> -			(st->buf[1] << 4) |
> -			((st->buf[2] >> 4) & 0xF);
> -	mutex_unlock(&st->buf_lock);
> -
> -	return ret;
> -}
> -
> -static int adis16060_read_raw(struct iio_dev *indio_dev,
> -			      struct iio_chan_spec const *chan,
> -			      int *val, int *val2,
> -			      long mask)
> -{
> -	u16 tval = 0;
> -	int ret;
> -
> -	switch (mask) {
> -	case IIO_CHAN_INFO_RAW:
> -		ret = adis16060_spi_write_then_read(indio_dev,
> -						    chan->address, &tval);
> -		if (ret < 0)
> -			return ret;
> -
> -		*val = tval;
> -		return IIO_VAL_INT;
> -	case IIO_CHAN_INFO_OFFSET:
> -		*val = -7;
> -		*val2 = 461117;
> -		return IIO_VAL_INT_PLUS_MICRO;
> -	case IIO_CHAN_INFO_SCALE:
> -		*val = 0;
> -		*val2 = 34000;
> -		return IIO_VAL_INT_PLUS_MICRO;
> -	}
> -
> -	return -EINVAL;
> -}
> -
> -static const struct iio_info adis16060_info = {
> -	.read_raw = adis16060_read_raw,
> -};
> -
> -static const struct iio_chan_spec adis16060_channels[] = {
> -	{
> -		.type = IIO_ANGL_VEL,
> -		.modified = 1,
> -		.channel2 = IIO_MOD_Z,
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> -		.address = ADIS16060_GYRO,
> -	}, {
> -		.type = IIO_VOLTAGE,
> -		.indexed = 1,
> -		.channel = 0,
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> -		.address = ADIS16060_AIN1,
> -	}, {
> -		.type = IIO_VOLTAGE,
> -		.indexed = 1,
> -		.channel = 1,
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> -		.address = ADIS16060_AIN2,
> -	}, {
> -		.type = IIO_TEMP,
> -		.indexed = 1,
> -		.channel = 0,
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> -		BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE),
> -		.address = ADIS16060_TEMP_OUT,
> -	}
> -};
> -
> -static int adis16060_r_probe(struct spi_device *spi)
> -{
> -	int ret;
> -	struct adis16060_state *st;
> -	struct iio_dev *indio_dev;
> -
> -	/* setup the industrialio driver allocated elements */
> -	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
> -	if (!indio_dev)
> -		return -ENOMEM;
> -	/* this is only used for removal purposes */
> -	spi_set_drvdata(spi, indio_dev);
> -	st = iio_priv(indio_dev);
> -	st->us_r = spi;
> -	mutex_init(&st->buf_lock);
> -
> -	indio_dev->name = spi->dev.driver->name;
> -	indio_dev->dev.parent = &spi->dev;
> -	indio_dev->info = &adis16060_info;
> -	indio_dev->modes = INDIO_DIRECT_MODE;
> -	indio_dev->channels = adis16060_channels;
> -	indio_dev->num_channels = ARRAY_SIZE(adis16060_channels);
> -
> -	ret = devm_iio_device_register(&spi->dev, indio_dev);
> -	if (ret)
> -		return ret;
> -
> -	adis16060_iio_dev = indio_dev;
> -	return 0;
> -}
> -
> -static int adis16060_w_probe(struct spi_device *spi)
> -{
> -	int ret;
> -	struct iio_dev *indio_dev = adis16060_iio_dev;
> -	struct adis16060_state *st;
> -
> -	if (!indio_dev) {
> -		ret =  -ENODEV;
> -		goto error_ret;
> -	}
> -	st = iio_priv(indio_dev);
> -	spi_set_drvdata(spi, indio_dev);
> -	st->us_w = spi;
> -	return 0;
> -
> -error_ret:
> -	return ret;
> -}
> -
> -static int adis16060_w_remove(struct spi_device *spi)
> -{
> -	return 0;
> -}
> -
> -static struct spi_driver adis16060_r_driver = {
> -	.driver = {
> -		.name = "adis16060_r",
> -	},
> -	.probe = adis16060_r_probe,
> -};
> -
> -static struct spi_driver adis16060_w_driver = {
> -	.driver = {
> -		.name = "adis16060_w",
> -	},
> -	.probe = adis16060_w_probe,
> -	.remove = adis16060_w_remove,
> -};
> -
> -static __init int adis16060_init(void)
> -{
> -	int ret;
> -
> -	ret = spi_register_driver(&adis16060_r_driver);
> -	if (ret < 0)
> -		return ret;
> -
> -	ret = spi_register_driver(&adis16060_w_driver);
> -	if (ret < 0) {
> -		spi_unregister_driver(&adis16060_r_driver);
> -		return ret;
> -	}
> -
> -	return 0;
> -}
> -module_init(adis16060_init);
> -
> -static __exit void adis16060_exit(void)
> -{
> -	spi_unregister_driver(&adis16060_w_driver);
> -	spi_unregister_driver(&adis16060_r_driver);
> -}
> -module_exit(adis16060_exit);
> -
> -MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
> -MODULE_DESCRIPTION("Analog Devices ADIS16060 Yaw Rate Gyroscope Driver");
> -MODULE_LICENSE("GPL v2");