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SubjectRe: [PATCH 2/3][V4] iio: imu: Add support for the ADIS16460 IMU
On Tue, 23 Jul 2019 10:36:39 +0300
Alexandru Ardelean <alexandru.ardelean@analog.com> wrote:

> The ADIS16460 device is a complete inertial system that includes a triaxial
> gyroscope and a triaxial accelerometer. It's more simplified design than
> that of the ADIS16480, and does not offer the triaxial magnetometers &
> pressure sensors. It does also have a temperature sensor (like the
> ADIS16480).
> Since it is part of the ADIS16XXX family, it re-uses parts of the ADIS
> library.
>
> Naturally, the register map is different and much more simplified than the
> ADIS16480 subfamily, so it cannot be integrated into that driver. A major
> difference is that the registers are not paged.
>
> One thing that is particularly special about it, is that it requires a
> higher delay between CS changes (i.e. when CS goes up, the spec recommends
> that it be brought down after a minimum of 16 uS).
> Other ADIS chips require (via spec) a minimum of 2 uS between CS changes.
> The kernel's 10 uS default should be fine for those other chips; they
> haven't been tested with lower CS change delays yet.
>
> Datasheet:
> https://www.analog.com/media/en/technical-documentation/data-sheets/adis16460.pdf
>
> Signed-off-by: Dragos Bogdan <dragos.bogdan@analog.com>
> Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Applied to the togreg branch of iio.git and pushed out as testing.

Note there was a typo / variable naming inconsistency that I fixed up.
See inline.

Thanks,

Jonathan

> ---
> MAINTAINERS | 7 +
> drivers/iio/imu/Kconfig | 12 +
> drivers/iio/imu/Makefile | 1 +
> drivers/iio/imu/adis16460.c | 489 ++++++++++++++++++++++++++++++++++++
> 4 files changed, 509 insertions(+)
> create mode 100644 drivers/iio/imu/adis16460.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 783569e3c4b4..f7de89e82e35 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -945,6 +945,13 @@ L: linux-iio@vger.kernel.org
> F: include/linux/iio/imu/adis.h
> F: drivers/iio/imu/adis.c
>
> +ANALOG DEVICES INC ADIS16460 DRIVER
> +M: Dragos Bogdan <dragos.bogdan@analog.com>
> +S: Supported
> +L: linux-iio@vger.kernel.org
> +W: http://ez.analog.com/community/linux-device-drivers
> +F: drivers/iio/imu/adis16460.c
> +
> ANALOG DEVICES INC ADP5061 DRIVER
> M: Stefan Popa <stefan.popa@analog.com>
> L: linux-pm@vger.kernel.org
> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
> index 4957e6df447e..f3c7282321a8 100644
> --- a/drivers/iio/imu/Kconfig
> +++ b/drivers/iio/imu/Kconfig
> @@ -17,6 +17,18 @@ config ADIS16400
> adis16365, adis16400 and adis16405 triaxial inertial sensors
> (adis16400 series also have magnetometers).
>
> +config ADIS16460
> + tristate "Analog Devices ADIS16460 and similar IMU driver"
> + depends on SPI
> + select IIO_ADIS_LIB
> + select IIO_ADIS_LIB_BUFFER if IIO_BUFFER
> + help
> + Say yes here to build support for Analog Devices ADIS16460 inertial
> + sensor.
> +
> + To compile this driver as a module, choose M here: the module will be
> + called adis16460.
> +
> config ADIS16480
> tristate "Analog Devices ADIS16480 and similar IMU driver"
> depends on SPI
> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
> index 9e452fce1aaf..4a6958865504 100644
> --- a/drivers/iio/imu/Makefile
> +++ b/drivers/iio/imu/Makefile
> @@ -5,6 +5,7 @@
>
> # When adding new entries keep the list in alphabetical order
> obj-$(CONFIG_ADIS16400) += adis16400.o
> +obj-$(CONFIG_ADIS16460) += adis16460.o
> obj-$(CONFIG_ADIS16480) += adis16480.o
>
> adis_lib-y += adis.o
> diff --git a/drivers/iio/imu/adis16460.c b/drivers/iio/imu/adis16460.c
> new file mode 100644
> index 000000000000..db713cba75a2
> --- /dev/null
> +++ b/drivers/iio/imu/adis16460.c
> @@ -0,0 +1,489 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * ADIS16460 IMU driver
> + *
> + * Copyright 2019 Analog Devices Inc.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/module.h>
> +#include <linux/spi/spi.h>
> +
> +#include <linux/iio/iio.h>
> +#include <linux/iio/imu/adis.h>
> +
> +#include <linux/debugfs.h>
> +
> +#define ADIS16460_REG_FLASH_CNT 0x00
> +#define ADIS16460_REG_DIAG_STAT 0x02
> +#define ADIS16460_REG_X_GYRO_LOW 0x04
> +#define ADIS16460_REG_X_GYRO_OUT 0x06
> +#define ADIS16460_REG_Y_GYRO_LOW 0x08
> +#define ADIS16460_REG_Y_GYRO_OUT 0x0A
> +#define ADIS16460_REG_Z_GYRO_LOW 0x0C
> +#define ADIS16460_REG_Z_GYRO_OUT 0x0E
> +#define ADIS16460_REG_X_ACCL_LOW 0x10
> +#define ADIS16460_REG_X_ACCL_OUT 0x12
> +#define ADIS16460_REG_Y_ACCL_LOW 0x14
> +#define ADIS16460_REG_Y_ACCL_OUT 0x16
> +#define ADIS16460_REG_Z_ACCL_LOW 0x18
> +#define ADIS16460_REG_Z_ACCL_OUT 0x1A
> +#define ADIS16460_REG_SMPL_CNTR 0x1C
> +#define ADIS16460_REG_TEMP_OUT 0x1E
> +#define ADIS16460_REG_X_DELT_ANG 0x24
> +#define ADIS16460_REG_Y_DELT_ANG 0x26
> +#define ADIS16460_REG_Z_DELT_ANG 0x28
> +#define ADIS16460_REG_X_DELT_VEL 0x2A
> +#define ADIS16460_REG_Y_DELT_VEL 0x2C
> +#define ADIS16460_REG_Z_DELT_VEL 0x2E
> +#define ADIS16460_REG_MSC_CTRL 0x32
> +#define ADIS16460_REG_SYNC_SCAL 0x34
> +#define ADIS16460_REG_DEC_RATE 0x36
> +#define ADIS16460_REG_FLTR_CTRL 0x38
> +#define ADIS16460_REG_GLOB_CMD 0x3E
> +#define ADIS16460_REG_X_GYRO_OFF 0x40
> +#define ADIS16460_REG_Y_GYRO_OFF 0x42
> +#define ADIS16460_REG_Z_GYRO_OFF 0x44
> +#define ADIS16460_REG_X_ACCL_OFF 0x46
> +#define ADIS16460_REG_Y_ACCL_OFF 0x48
> +#define ADIS16460_REG_Z_ACCL_OFF 0x4A
> +#define ADIS16460_REG_LOT_ID1 0x52
> +#define ADIS16460_REG_LOT_ID2 0x54
> +#define ADIS16460_REG_PROD_ID 0x56
> +#define ADIS16460_REG_SERIAL_NUM 0x58
> +#define ADIS16460_REG_CAL_SGNTR 0x60
> +#define ADIS16460_REG_CAL_CRC 0x62
> +#define ADIS16460_REG_CODE_SGNTR 0x64
> +#define ADIS16460_REG_CODE_CRC 0x66
> +
> +struct adis16460_chip_info {
> + unsigned int num_channels;
> + const struct iio_chan_spec *channels;
> + unsigned int gyro_max_val;
> + unsigned int gyro_max_scale;
> + unsigned int accel_max_val;
> + unsigned int accel_max_scale;
> +};
> +
> +struct adis16460 {
> + const struct adis16460_chip_info *chip_info;
> + struct adis adis;
> +};
> +
> +#ifdef CONFIG_DEBUG_FS
> +
> +static int adis16460_show_serial_number(void *arg, u64 *val)
> +{
> + struct adis16460 *adis16460 = arg;
> + u16 serial;
> + int ret;
> +
> + ret = adis_read_reg_16(&adis16460->adis, ADIS16460_REG_SERIAL_NUM,
> + &serial);
> + if (ret < 0)
> + return ret;
> +
> + *val = serial;
> +
> + return 0;
> +}
> +DEFINE_SIMPLE_ATTRIBUTE(adis16460_serial_number_fops,
> + adis16460_show_serial_number, NULL, "0x%.4llx\n");
> +
> +static int adis16460_show_product_id(void *arg, u64 *val)
> +{
> + struct adis16460 *adis16460 = arg;
> + u16 prod_id;
> + int ret;
> +
> + ret = adis_read_reg_16(&adis16460->adis, ADIS16460_REG_PROD_ID,
> + &prod_id);
> + if (ret < 0)
> + return ret;
> +
> + *val = prod_id;
> +
> + return 0;
> +}
> +DEFINE_SIMPLE_ATTRIBUTE(adis16460_product_id_fops,
> + adis16460_show_product_id, NULL, "%llu\n");
> +
> +static int adis16460_show_flash_count(void *arg, u64 *val)
> +{
> + struct adis16460 *adis16460 = arg;
> + u32 flash_count;
> + int ret;
> +
> + ret = adis_read_reg_32(&adis16460->adis, ADIS16460_REG_FLASH_CNT,
> + &flash_count);
> + if (ret < 0)
> + return ret;
> +
> + *val = flash_count;
> +
> + return 0;
> +}
> +DEFINE_SIMPLE_ATTRIBUTE(adis16460_flash_count_fops,
> + adis16460_show_flash_count, NULL, "%lld\n");
> +
> +static int adis16460_debugfs_init(struct iio_dev *indio_dev)
> +{
> + struct adis16460 *adis16460 = iio_priv(indio_dev);
> +
> + debugfs_create_file("serial_number", 0400, indio_dev->debugfs_dentry,
> + adis16460, &adis16460_serial_number_fops);
> + debugfs_create_file("product_id", 0400, indio_dev->debugfs_dentry,
> + adis16460, &adis16460_product_id_fops);
> + debugfs_create_file("flash_count", 0400, indio_dev->debugfs_dentry,
> + adis16460, &adis16460_flash_count_fops);
> +
> + return 0;
> +}
> +
> +#else
> +
> +static int adis16460_debugfs_init(struct iio_dev *indio_dev)
> +{
> + return 0;
> +}
> +
> +#endif
> +
> +static int adis16460_set_freq(struct iio_dev *indio_dev, int val, int val2)
> +{
> + struct adis16460 *st = iio_priv(indio_dev);
> + unsigned int t;
> +
> + t = val * 1000 + val2 / 1000;
> + if (t <= 0)
> + return -EINVAL;
> +
> + t = 2048000 / t;
> + if (t > 2048)
> + t = 2048;
> +
> + if (t != 0)
> + t--;
> +
> + return adis_write_reg_16(&st->adis, ADIS16460_REG_DEC_RATE, t);
> +}
> +
> +static int adis16460_get_freq(struct iio_dev *indio_dev, int *val, int *val2)
> +{
> + struct adis16460 *st = iio_priv(indio_dev);
> + uint16_t t;
> + int ret;
> + unsigned int freq;
> +
> + ret = adis_read_reg_16(&st->adis, ADIS16460_REG_DEC_RATE, &t);
> + if (ret < 0)
> + return ret;
> +
> + freq = 2048000 / (t + 1);
> + *val = freq / 1000;
> + *val2 = (freq % 1000) * 1000;
> +
> + return IIO_VAL_INT_PLUS_MICRO;
> +}
> +
> +static int adis16460_read_raw(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan, int *val, int *val2, long info)
> +{
> + struct adis16460 *st = iio_priv(indio_dev);
> +
> + switch (info) {
> + case IIO_CHAN_INFO_RAW:
> + return adis_single_conversion(indio_dev, chan, 0, val);
> + case IIO_CHAN_INFO_SCALE:
> + switch (chan->type) {
> + case IIO_ANGL_VEL:
> + *val = st->chip_info->gyro_max_scale;
> + *val2 = st->chip_info->gyro_max_val;
> + return IIO_VAL_FRACTIONAL;
> + case IIO_ACCEL:
> + *val = st->chip_info->accel_max_scale;
> + *val2 = st->chip_info->accel_max_val;
> + return IIO_VAL_FRACTIONAL;
> + case IIO_TEMP:
> + *val = 50; /* 50 milli degrees Celsius/LSB */
> + return IIO_VAL_INT;
> + default:
> + return -EINVAL;
> + }
> + case IIO_CHAN_INFO_OFFSET:
> + *val = 500; /* 25 degrees Celsius = 0x0000 */
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_SAMP_FREQ:
> + return adis16460_get_freq(indio_dev, val, val2);
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int adis16460_write_raw(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan, int val, int val2, long info)
> +{
> + switch (info) {
> + case IIO_CHAN_INFO_SAMP_FREQ:
> + return adis16460_set_freq(indio_dev, val, val2);
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +enum {
> + ADIS16460_SCAN_GYRO_X,
> + ADIS16460_SCAN_GYRO_Y,
> + ADIS16460_SCAN_GYRO_Z,
> + ADIS16460_SCAN_ACCEL_X,
> + ADIS16460_SCAN_ACCEL_Y,
> + ADIS16460_SCAN_ACCEL_Z,
> + ADIS16460_SCAN_TEMP,
> +};
> +
> +#define ADIS16460_MOD_CHANNEL(_type, _mod, _address, _si, _bits) \
> + { \
> + .type = (_type), \
> + .modified = 1, \
> + .channel2 = (_mod), \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> + .address = (_address), \
> + .scan_index = (_si), \
> + .scan_type = { \
> + .sign = 's', \
> + .realbits = (_bits), \
> + .storagebits = (_bits), \
> + .endianness = IIO_BE, \
> + }, \
> + }
> +
> +#define ADIS16460_GYRO_CHANNEL(_mod) \
> + ADIS16460_MOD_CHANNEL(IIO_ANGL_VEL, IIO_MOD_ ## _mod, \
> + ADIS16460_REG_ ## _mod ## _GYRO_LOW, ADIS16460_SCAN_GYRO_ ## _mod, \
> + 32)
> +
> +#define ADIS16460_ACCEL_CHANNEL(_mod) \
> + ADIS16460_MOD_CHANNEL(IIO_ACCEL, IIO_MOD_ ## _mod, \
> + ADIS16460_REG_ ## _mod ## _ACCL_LOW, ADIS16460_SCAN_ACCEL_ ## _mod, \
> + 32)
> +
> +#define ADIS16460_TEMP_CHANNEL() { \
> + .type = IIO_TEMP, \
> + .indexed = 1, \
> + .channel = 0, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
> + BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_OFFSET), \
> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> + .address = ADIS16460_REG_TEMP_OUT, \
> + .scan_index = ADIS16460_SCAN_TEMP, \
> + .scan_type = { \
> + .sign = 's', \
> + .realbits = 16, \
> + .storagebits = 16, \
> + .endianness = IIO_BE, \
> + }, \
> + }
> +
> +static const struct iio_chan_spec adis16460_channels[] = {
> + ADIS16460_GYRO_CHANNEL(X),
> + ADIS16460_GYRO_CHANNEL(Y),
> + ADIS16460_GYRO_CHANNEL(Z),
> + ADIS16460_ACCEL_CHANNEL(X),
> + ADIS16460_ACCEL_CHANNEL(Y),
> + ADIS16460_ACCEL_CHANNEL(Z),
> + ADIS16460_TEMP_CHANNEL(),
> + IIO_CHAN_SOFT_TIMESTAMP(7)
> +};
> +
> +static const struct adis16460_chip_info adis16460_chip_info = {
> + .channels = adis16460_channels,
> + .num_channels = ARRAY_SIZE(adis16460_channels),
> + /*
> + * storing the value in rad/degree and the scale in degree
> + * gives us the result in rad and better precession than
> + * storing the scale directly in rad.
> + */
> + .gyro_max_val = IIO_RAD_TO_DEGREE(200 << 16),
> + .gyro_max_scale = 1,
> + .accel_max_val = IIO_M_S_2_TO_G(20000 << 16),
> + .accel_max_scale = 5,
> +};
> +
> +static const struct iio_info adis16460_info = {
> + .read_raw = &adis16460_read_raw,
> + .write_raw = &adis16460_write_raw,
> + .update_scan_mode = adis_update_scan_mode,
> + .debugfs_reg_access = adis_debugfs_reg_access,
> +};
> +
> +static int adis16460_enable_irq(struct adis *adis, bool enable)
> +{
> + /*
> + * There is no way to gate the data-ready signal internally inside the
> + * ADIS16460 :(
> + */
> + if (enable)
> + enable_irq(adis->spi->irq);
> + else
> + disable_irq(adis->spi->irq);
> +
> + return 0;
> +}
> +
> +static int adis16460_initial_setup(struct iio_dev *indio_dev)
> +{
> + struct adis16460 *st = iio_priv(indio_dev);
> + uint16_t prod_id;
> + unsigned int device_id;
> + int ret;
> +
> + adis_reset(&st->adis);
> + msleep(222);
> +
> + ret = adis_write_reg_16(&st->adis, ADIS16460_REG_GLOB_CMD, BIT(1));
> + if (ret)
> + return ret;
> + msleep(75);
> +
> + ret = adis_check_status(&st->adis);
> + if (ret)
> + return ret;
> +
> + ret = adis_read_reg_16(&st->adis, ADIS16460_REG_PROD_ID, &prod_id);
> + if (ret)
> + return ret;
> +
> + ret = sscanf(indio_dev->name, "adis%u\n", &device_id);
> + if (ret != 1)
> + return -EINVAL;
> +
> + if (prod_id != device_id)
> + dev_warn(&indio_dev->dev, "Device ID(%u) and product ID(%u) do not match.",
> + device_id, prod_id);
> +
> + return 0;
> +}
> +
> +#define ADIS16460_DIAG_STAT_IN_CLK_OOS 7
> +#define ADIS16460_DIAG_STAT_FLASH_MEM 6
> +#define ADIS16460_DIAG_STAT_SELF_TEST 5
> +#define ADIS16460_DIAG_STAT_OVERRANGE 4
> +#define ADIS16460_DIAG_STAT_SPI_COMM 3
> +#define ADIS16460_DIAG_STAT_FLASH_UPT 2
> +
> +static const char * const adis16460_status_error_msgs[] = {
> + [ADIS16460_DIAG_STAT_IN_CLK_OOS] = "Input clock out of sync",
> + [ADIS16460_DIAG_STAT_FLASH_MEM] = "Flash memory failure",
> + [ADIS16460_DIAG_STAT_SELF_TEST] = "Self test diagnostic failure",
> + [ADIS16460_DIAG_STAT_OVERRANGE] = "Sensor overrange",
> + [ADIS16460_DIAG_STAT_SPI_COMM] = "SPI communication failure",
> + [ADIS16460_DIAG_STAT_FLASH_UPT] = "Flash update failure",
> +};
> +
> +static const struct adis_data adis16460_data = {
> + .diag_stat_reg = ADIS16460_REG_DIAG_STAT,
> + .glob_cmd_reg = ADIS16460_REG_GLOB_CMD,
> + .has_paging = false,
> + .read_delay = 5,
> + .write_delay = 5,
> + .cs_change_delay = 16,
> + .status_error_msgs = adis16460_status_error_msgs,
> + .status_error_mask = BIT(ADIS16460_DIAG_STAT_IN_CLK_OOS) |
> + BIT(ADIS16460_DIAG_STAT_FLASH_MEM) |
> + BIT(ADIS16460_DIAG_STAT_SELF_TEST) |
> + BIT(ADIS16460_DIAG_STAT_OVERRANGE) |
> + BIT(ADIS16460_DIAG_STAT_SPI_COMM) |
> + BIT(ADIS16460_DIAG_STAT_FLASH_UPT),
> + .enable_irq = adis16460_enable_irq,
> +};
> +
> +static int adis16460_probe(struct spi_device *spi)
> +{
> + struct iio_dev *indio_dev;
> + struct adis16460 *st;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
> + if (indio_dev == NULL)
> + return -ENOMEM;
> +
> + spi_set_drvdata(spi, indio_dev);
> +
> + st = iio_priv(indio_dev);
> +
> + st->chip_info = &adis16460_chip_info;
> + indio_dev->dev.parent = &spi->dev;
> + indio_dev->name = spi_get_device_id(spi)->name;
> + indio_dev->channels = st->chip_info->channels;
> + indio_dev->num_channels = st->chip_info->num_channels;
> + indio_dev->info = &adis16460_info;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> +
> + ret = adis_init(&st->adis, indio_dev, spi, &adis16460_data);
> + if (ret)
> + return ret;
> +
> + ret = adis_setup_buffer_and_trigger(&st->adis, indio_dev, NULL);
> + if (ret)
> + return ret;
> +
> + adis16460_enable_irq(&st->adis, 0);
> +
> + ret = adis16460_initial_setup(indio_dev);
> + if (ret)
> + goto error_cleanup_buffer;
> +
> + ret = iio_device_register(indio_dev);
> + if (ret)
> + goto error_cleanup_buffer;
> +
> + adis16460_debugfs_init(indio_dev);
> +
> + return 0;
> +
> +error_cleanup_buffer:
> + adis_cleanup_buffer_and_trigger(&st->adis, indio_dev);
> + return ret;
> +}
> +
> +static int adis16460_remove(struct spi_device *spi)
> +{
> + struct iio_dev *indio_dev = spi_get_drvdata(spi);
> + struct adis16460 *st = iio_priv(indio_dev);
> +
> + iio_device_unregister(indio_dev);
> +
> + adis_cleanup_buffer_and_trigger(&st->adis, indio_dev);
> +
> + return 0;
> +}
> +
> +static const struct spi_device_id adis16460_ids[] = {
this is plural, it's used below as singular
*_id;

I've fixed it up as ids everywhere.

Please check the result.

Jonathan

> + { "adis16460", 0 },
> + {}
> +};
> +MODULE_DEVICE_TABLE(spi, adis16460_id);
> +
> +static const struct of_device_id adis16460_of_match[] = {
> + { .compatible = "adi,adis16460" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, adis16460_of_match);
> +
> +static struct spi_driver adis16460_driver = {
> + .driver = {
> + .name = "adis16460",
> + .of_match_table = adis16460_of_match,
> + },
> + .id_table = adis16460_ids,
> + .probe = adis16460_probe,
> + .remove = adis16460_remove,
> +};
> +module_spi_driver(adis16460_driver);
> +
> +MODULE_AUTHOR("Dragos Bogdan <dragos.bogdan@analog.com>");
> +MODULE_DESCRIPTION("Analog Devices ADIS16460 IMU driver");
> +MODULE_LICENSE("GPL");

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