[PATCH 2/3][V4] iio: imu: Add support for the ADIS16460 IMU

Alexandru Ardelean
2019-07-23T07:37:09Z

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>
---
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[] = {
+ { "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");
--
2.20.1