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Message-Id: <20241014-wip-bl-ad3552r-axi-v0-iio-testing-v6-7-eeef0c1e0e56@baylibre.com>
Date: Mon, 14 Oct 2024 12:08:13 +0200
From: Angelo Dureghello <adureghello@...libre.com>
To: Nuno Sá <nuno.sa@...log.com>,
Lars-Peter Clausen <lars@...afoo.de>,
Michael Hennerich <Michael.Hennerich@...log.com>,
Jonathan Cameron <jic23@...nel.org>, Rob Herring <robh@...nel.org>,
Krzysztof Kozlowski <krzk+dt@...nel.org>,
Conor Dooley <conor+dt@...nel.org>,
Olivier Moysan <olivier.moysan@...s.st.com>
Cc: linux-iio@...r.kernel.org, devicetree@...r.kernel.org,
linux-kernel@...r.kernel.org, dlechner@...libre.com,
Mark Brown <broonie@...nel.org>,
Angelo Dureghello <adureghello@...libre.com>
Subject: [PATCH v6 7/8] iio: dac: ad3552r: add high-speed platform driver
From: Angelo Dureghello <adureghello@...libre.com>
Add High Speed ad3552r platform driver.
The ad3552r DAC is controlled by a custom (fpga-based) DAC IP
through the current AXI backend, or similar alternative IIO backend.
Compared to the existing driver (ad3552r.c), that is a simple SPI
driver, this driver is coupled with a DAC IIO backend that finally
controls the ad3552r by a fpga-based "QSPI+DDR" interface, to reach
maximum transfer rate of 33MUPS using dma stream capabilities.
All commands involving QSPI bus read/write are delegated to the backend
through the provided APIs for bus read/write.
Signed-off-by: Angelo Dureghello <adureghello@...libre.com>
---
drivers/iio/dac/Kconfig | 14 ++
drivers/iio/dac/Makefile | 1 +
drivers/iio/dac/ad3552r-hs.c | 526 +++++++++++++++++++++++++++++++++++++++++++
drivers/iio/dac/ad3552r-hs.h | 18 ++
drivers/iio/dac/ad3552r.h | 7 +
5 files changed, 566 insertions(+)
diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
index fa091995d002..fc11698e88f2 100644
--- a/drivers/iio/dac/Kconfig
+++ b/drivers/iio/dac/Kconfig
@@ -6,6 +6,20 @@
menu "Digital to analog converters"
+config AD3552R_HS
+ tristate "Analog Devices AD3552R DAC High Speed driver"
+ select ADI_AXI_DAC
+ help
+ Say yes here to build support for Analog Devices AD3552R
+ Digital to Analog Converter High Speed driver.
+
+ The driver requires the assistance of an IP core to operate,
+ since data is streamed into target device via DMA, sent over a
+ QSPI + DDR (Double Data Rate) bus.
+
+ To compile this driver as a module, choose M here: the
+ module will be called ad3552r-hs.
+
config AD3552R
tristate "Analog Devices AD3552R DAC driver"
depends on SPI_MASTER
diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
index c92de0366238..d92e08ca93ca 100644
--- a/drivers/iio/dac/Makefile
+++ b/drivers/iio/dac/Makefile
@@ -4,6 +4,7 @@
#
# When adding new entries keep the list in alphabetical order
+obj-$(CONFIG_AD3552R_HS) += ad3552r-hs.o ad3552r-common.o
obj-$(CONFIG_AD3552R) += ad3552r.o ad3552r-common.o
obj-$(CONFIG_AD5360) += ad5360.o
obj-$(CONFIG_AD5380) += ad5380.o
diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
new file mode 100644
index 000000000000..cb29a600e141
--- /dev/null
+++ b/drivers/iio/dac/ad3552r-hs.c
@@ -0,0 +1,526 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Analog Devices AD3552R
+ * Digital to Analog converter driver, High Speed version
+ *
+ * Copyright 2024 Analog Devices Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iio/backend.h>
+#include <linux/iio/buffer.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/units.h>
+
+#include "ad3552r.h"
+#include "ad3552r-hs.h"
+
+struct ad3552r_hs_state {
+ const struct ad3552r_model_data *model_data;
+ struct gpio_desc *reset_gpio;
+ struct device *dev;
+ struct iio_backend *back;
+ bool single_channel;
+ struct ad3552r_hs_platform_data *data;
+ bool ddr_mode;
+};
+
+static int ad3552r_qspi_update_reg_bits(struct ad3552r_hs_state *st,
+ u32 reg, u32 mask, u32 val,
+ size_t xfer_size)
+{
+ u32 rval;
+ int err;
+
+ err = st->data->bus_reg_read(st->back, reg, &rval, xfer_size);
+ if (err)
+ return err;
+
+ rval &= ~mask;
+ rval |= val;
+
+ return st->data->bus_reg_write(st->back, reg, rval, xfer_size);
+}
+
+static int ad3552r_hs_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct ad3552r_hs_state *st = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ: {
+ int sclk;
+
+ ret = iio_backend_read_raw(st->back, chan, &sclk, 0,
+ IIO_CHAN_INFO_FREQUENCY);
+ if (ret != IIO_VAL_INT)
+ return -EINVAL;
+
+ /* Using 4 lanes (QSPI) */
+ *val = DIV_ROUND_CLOSEST(sclk * 4 * (1 + st->ddr_mode),
+ chan->scan_type.storagebits);
+
+ return IIO_VAL_INT;
+ }
+ case IIO_CHAN_INFO_RAW:
+ ret = st->data->bus_reg_read(st->back,
+ AD3552R_REG_ADDR_CH_DAC_16B(chan->channel),
+ val, 2);
+ if (ret)
+ return ret;
+
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad3552r_hs_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct ad3552r_hs_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
+ return st->data->bus_reg_write(st->back,
+ AD3552R_REG_ADDR_CH_DAC_16B(chan->channel),
+ val, 2);
+ }
+ unreachable();
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct ad3552r_hs_state *st = iio_priv(indio_dev);
+ struct iio_backend_data_fmt fmt = {
+ .type = IIO_BACKEND_DATA_UNSIGNED
+ };
+ int loop_len, val, err;
+
+ /* Inform DAC chip to switch into DDR mode */
+ err = ad3552r_qspi_update_reg_bits(st,
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+ AD3552R_MASK_SPI_CONFIG_DDR,
+ AD3552R_MASK_SPI_CONFIG_DDR, 1);
+ if (err)
+ return err;
+
+ /* Inform DAC IP to go for DDR mode from now on */
+ err = iio_backend_ddr_enable(st->back);
+ if (err) {
+ dev_warn(st->dev, "could not set DDR mode, not streaming");
+ goto exit_err;
+ }
+
+ st->ddr_mode = true;
+
+ switch (*indio_dev->active_scan_mask) {
+ case AD3552R_CH0_ACTIVE:
+ st->single_channel = true;
+ loop_len = 2;
+ val = AD3552R_REG_ADDR_CH_DAC_16B(0);
+ break;
+ case AD3552R_CH1_ACTIVE:
+ st->single_channel = true;
+ loop_len = 2;
+ val = AD3552R_REG_ADDR_CH_DAC_16B(1);
+ break;
+ case AD3552R_CH0_CH1_ACTIVE:
+ st->single_channel = false;
+ loop_len = 4;
+ val = AD3552R_REG_ADDR_CH_DAC_16B(1);
+ break;
+ default:
+ err = -EINVAL;
+ goto exit_err_ddr;
+ }
+
+ err = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_STREAM_MODE,
+ loop_len, 1);
+ if (err)
+ goto exit_err_ddr;
+
+ err = iio_backend_data_transfer_addr(st->back, val);
+ if (err)
+ goto exit_err_ddr;
+
+ err = iio_backend_data_format_set(st->back, 0, &fmt);
+ if (err)
+ goto exit_err_ddr;
+
+ err = iio_backend_data_stream_enable(st->back);
+ if (err)
+ goto exit_err_ddr;
+
+ return 0;
+
+exit_err_ddr:
+ iio_backend_ddr_disable(st->back);
+
+exit_err:
+ ad3552r_qspi_update_reg_bits(st,
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+ AD3552R_MASK_SPI_CONFIG_DDR,
+ 0, 1);
+
+ iio_backend_ddr_disable(st->back);
+
+ st->ddr_mode = false;
+
+ return err;
+}
+
+static int ad3552r_hs_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct ad3552r_hs_state *st = iio_priv(indio_dev);
+ int err;
+
+ err = iio_backend_data_stream_disable(st->back);
+ if (err)
+ return err;
+
+ /* Inform DAC to set in SDR mode */
+ err = ad3552r_qspi_update_reg_bits(st,
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+ AD3552R_MASK_SPI_CONFIG_DDR,
+ 0, 1);
+ if (err)
+ return err;
+
+ err = iio_backend_ddr_disable(st->back);
+ if (err)
+ return err;
+
+ st->ddr_mode = false;
+
+ return 0;
+}
+
+static int ad3552r_hs_set_output_range(struct ad3552r_hs_state *st,
+ unsigned int mode)
+{
+ return ad3552r_qspi_update_reg_bits(st,
+ AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE,
+ AD3552R_MASK_CH_OUTPUT_RANGE,
+ FIELD_PREP(AD3552R_MASK_CH0_RANGE, mode) |
+ FIELD_PREP(AD3552R_MASK_CH1_RANGE, mode),
+ 1);
+}
+
+static int ad3552r_hs_reset(struct ad3552r_hs_state *st)
+{
+ int err;
+
+ st->reset_gpio = devm_gpiod_get_optional(st->dev,
+ "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(st->reset_gpio))
+ return PTR_ERR(st->reset_gpio);
+
+ if (st->reset_gpio) {
+ fsleep(10);
+ gpiod_set_value_cansleep(st->reset_gpio, 1);
+ } else {
+ err = ad3552r_qspi_update_reg_bits(st,
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_A,
+ AD3552R_MASK_SOFTWARE_RESET,
+ AD3552R_MASK_SOFTWARE_RESET, 1);
+ if (err)
+ return err;
+ }
+ msleep(100);
+
+ return 0;
+}
+
+static int ad3552r_hs_scratch_pad_test(struct ad3552r_hs_state *st)
+{
+ int err, val;
+
+ err = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_SCRATCH_PAD,
+ AD3552R_SCRATCH_PAD_TEST_VAL1, 1);
+ if (err)
+ return err;
+
+ err = st->data->bus_reg_read(st->back, AD3552R_REG_ADDR_SCRATCH_PAD,
+ &val, 1);
+ if (err)
+ return err;
+
+ if (val != AD3552R_SCRATCH_PAD_TEST_VAL1) {
+ dev_err(st->dev,
+ "SCRATCH_PAD_TEST mismatch. Expected 0x%x, Read 0x%x\n",
+ AD3552R_SCRATCH_PAD_TEST_VAL1, val);
+ return -EIO;
+ }
+
+ err = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_SCRATCH_PAD,
+ AD3552R_SCRATCH_PAD_TEST_VAL2, 1);
+ if (err)
+ return err;
+
+ err = st->data->bus_reg_read(st->back, AD3552R_REG_ADDR_SCRATCH_PAD,
+ &val, 1);
+ if (err)
+ return err;
+
+ if (val != AD3552R_SCRATCH_PAD_TEST_VAL2) {
+ dev_err(st->dev,
+ "SCRATCH_PAD_TEST mismatch. Expected 0x%x, Read 0x%x\n",
+ AD3552R_SCRATCH_PAD_TEST_VAL2, val);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int ad3552r_hs_setup_custom_gain(struct ad3552r_hs_state *st,
+ u16 gain, u16 offset)
+{
+ int err;
+
+ err = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_CH_OFFSET(0),
+ offset, 1);
+ if (err)
+ return dev_err_probe(st->dev, err, "Error writing register\n");
+
+ err = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_CH_OFFSET(1),
+ offset, 1);
+ if (err)
+ return dev_err_probe(st->dev, err, "Error writing register\n");
+
+ err = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_CH_GAIN(0),
+ gain, 1);
+ if (err)
+ return dev_err_probe(st->dev, err, "Error writing register\n");
+
+ err = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_CH_GAIN(1),
+ gain, 1);
+ if (err)
+ return dev_err_probe(st->dev, err, "Error writing register\n");
+
+ return 0;
+}
+
+static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
+{
+ u8 gs_p, gs_n;
+ s16 goffs;
+ u16 id, rfb;
+ u16 gain = 0, offset = 0;
+ u32 val, range;
+ int err;
+
+ err = ad3552r_hs_reset(st);
+ if (err)
+ return err;
+
+ err = iio_backend_ddr_disable(st->back);
+ if (err)
+ return err;
+
+ err = ad3552r_hs_scratch_pad_test(st);
+ if (err)
+ return err;
+
+ err = st->data->bus_reg_read(st->back, AD3552R_REG_ADDR_PRODUCT_ID_L,
+ &val, 1);
+ if (err)
+ return err;
+
+ id = val;
+
+ err = st->data->bus_reg_read(st->back, AD3552R_REG_ADDR_PRODUCT_ID_H,
+ &val, 1);
+ if (err)
+ return err;
+
+ id |= val << 8;
+ if (id != st->model_data->chip_id)
+ dev_info(st->dev, "Chip ID error. Expected 0x%x, Read 0x%x\n",
+ AD3552R_ID, id);
+
+ err = st->data->bus_reg_write(st->back,
+ AD3552R_REG_ADDR_SH_REFERENCE_CONFIG,
+ 0, 1);
+ if (err)
+ return err;
+
+ err = st->data->bus_reg_write(st->back,
+ AD3552R_REG_ADDR_TRANSFER_REGISTER,
+ AD3552R_MASK_QUAD_SPI |
+ AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
+ if (err)
+ return err;
+
+ err = iio_backend_data_source_set(st->back, 0, IIO_BACKEND_EXTERNAL);
+ if (err)
+ return err;
+
+ err = iio_backend_data_source_set(st->back, 1, IIO_BACKEND_EXTERNAL);
+ if (err)
+ return err;
+
+ err = ad3552r_get_ref_voltage(st->dev);
+ if (err < 0)
+ return err;
+
+ val = err;
+
+ err = ad3552r_qspi_update_reg_bits(st,
+ AD3552R_REG_ADDR_SH_REFERENCE_CONFIG,
+ AD3552R_MASK_REFERENCE_VOLTAGE_SEL,
+ val, 1);
+ if (err)
+ return err;
+
+ err = ad3552r_get_drive_strength(st->dev, &val);
+ if (!err) {
+ err = ad3552r_qspi_update_reg_bits(st,
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+ AD3552R_MASK_SDO_DRIVE_STRENGTH,
+ val, 1);
+ if (err)
+ return err;
+ }
+
+ struct fwnode_handle *child __free(fwnode_handle) =
+ device_get_named_child_node(st->dev, "channel");
+ if (!child)
+ return -EINVAL;
+
+ /*
+ * One of "adi,output-range-microvolt" or "custom-output-range-config"
+ * must be available in fdt.
+ */
+ err = ad3552r_get_output_range(st->dev, st->model_data, child, &range);
+ if (!err)
+ return ad3552r_hs_set_output_range(st, range);
+ if (err != -ENOENT)
+ return err;
+
+ err = ad3552r_get_custom_gain(st->dev, child, &gs_p, &gs_n, &rfb,
+ &goffs);
+ if (err)
+ return err;
+
+ gain = ad3552r_calc_custom_gain(gs_p, gs_n, goffs);
+ offset = abs(goffs);
+
+ return ad3552r_hs_setup_custom_gain(st, gain, offset);
+}
+
+static const struct iio_buffer_setup_ops ad3552r_hs_buffer_setup_ops = {
+ .postenable = ad3552r_hs_buffer_postenable,
+ .predisable = ad3552r_hs_buffer_predisable,
+};
+
+#define AD3552R_CHANNEL(ch) { \
+ .type = IIO_VOLTAGE, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .output = 1, \
+ .indexed = 1, \
+ .channel = (ch), \
+ .scan_index = (ch), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_BE, \
+ } \
+}
+
+static const struct iio_chan_spec ad3552r_hs_channels[] = {
+ AD3552R_CHANNEL(0),
+ AD3552R_CHANNEL(1),
+};
+
+static const struct iio_info ad3552r_hs_info = {
+ .read_raw = &ad3552r_hs_read_raw,
+ .write_raw = &ad3552r_hs_write_raw,
+};
+
+static int ad3552r_hs_probe(struct platform_device *pdev)
+{
+ struct ad3552r_hs_state *st;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+ st->dev = &pdev->dev;
+
+ st->data = pdev->dev.platform_data;
+ if (!st->data)
+ dev_err_probe(st->dev, -ENODEV, "No platform data !");
+
+ st->back = devm_iio_backend_get(&pdev->dev, NULL);
+ if (IS_ERR(st->back))
+ return PTR_ERR(st->back);
+
+ ret = devm_iio_backend_enable(&pdev->dev, st->back);
+ if (ret)
+ return ret;
+
+ st->model_data = device_get_match_data(&pdev->dev);
+
+ indio_dev->name = "ad3552r";
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->setup_ops = &ad3552r_hs_buffer_setup_ops;
+ indio_dev->channels = ad3552r_hs_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ad3552r_hs_channels);
+ indio_dev->info = &ad3552r_hs_info;
+
+ ret = devm_iio_backend_request_buffer(&pdev->dev, st->back, indio_dev);
+ if (ret)
+ return ret;
+
+ ret = ad3552r_hs_setup(st);
+ if (ret)
+ return ret;
+
+ return devm_iio_device_register(&pdev->dev, indio_dev);
+}
+
+static const struct ad3552r_model_data ad3552r_model_data = {
+ .model_name = "ad3552r",
+ .chip_id = AD3552R_ID,
+ .num_hw_channels = 2,
+ .ranges_table = ad3552r_ch_ranges,
+ .num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
+};
+
+static const struct of_device_id ad3552r_hs_of_id[] = {
+ { .compatible = "adi,ad3552r", .data = &ad3552r_model_data },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ad3552r_hs_of_id);
+
+static struct platform_driver axi_ad3552r_driver = {
+ .driver = {
+ .name = "ad3552r-axi",
+ .of_match_table = ad3552r_hs_of_id,
+ },
+ .probe = ad3552r_hs_probe,
+};
+module_platform_driver(axi_ad3552r_driver);
+
+MODULE_AUTHOR("Dragos Bogdan <dragos.bogdan@...log.com>");
+MODULE_AUTHOR("Angelo Dureghello <adueghello@...libre.com>");
+MODULE_DESCRIPTION("AD3552R Driver - AXI IP version");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(IIO_AD3552R);
diff --git a/drivers/iio/dac/ad3552r-hs.h b/drivers/iio/dac/ad3552r-hs.h
new file mode 100644
index 000000000000..dbf71d5e58c1
--- /dev/null
+++ b/drivers/iio/dac/ad3552r-hs.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2024 Analog Devices Inc.
+ * Copyright (c) 2024 Baylibre, SAS
+ */
+#ifndef __LINUX_PLATFORM_DATA_AD3552R_HS_H__
+#define __LINUX_PLATFORM_DATA_AD3552R_HS_H__
+
+struct iio_backend;
+
+struct ad3552r_hs_platform_data {
+ int (*bus_reg_read)(struct iio_backend *back, u32 reg, u32 *val,
+ size_t data_size);
+ int (*bus_reg_write)(struct iio_backend *back, u32 reg, u32 val,
+ size_t data_size);
+};
+
+#endif /* __LINUX_PLATFORM_DATA_AD3552R_HS_H__ */
diff --git a/drivers/iio/dac/ad3552r.h b/drivers/iio/dac/ad3552r.h
index 088eb8ecfac6..fc00ed4c2565 100644
--- a/drivers/iio/dac/ad3552r.h
+++ b/drivers/iio/dac/ad3552r.h
@@ -38,6 +38,8 @@
#define AD3552R_REG_ADDR_TRANSFER_REGISTER 0x0F
#define AD3552R_MASK_MULTI_IO_MODE GENMASK(7, 6)
#define AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE BIT(2)
+#define AD3552R_MASK_DUAL_SPI BIT(6)
+#define AD3552R_MASK_QUAD_SPI BIT(7)
#define AD3552R_REG_ADDR_INTERFACE_CONFIG_C 0x10
#define AD3552R_MASK_CRC_ENABLE (GENMASK(7, 6) |\
GENMASK(1, 0))
@@ -129,6 +131,11 @@
#define AD3552R_GAIN_SCALE 1000
#define AD3552R_LDAC_PULSE_US 100
+#define AD3552R_CH0_ACTIVE BIT(0)
+#define AD3552R_CH1_ACTIVE BIT(1)
+#define AD3552R_CH0_CH1_ACTIVE (AD3552R_CH0_ACTIVE | \
+ AD3552R_CH1_ACTIVE)
+
#define AD3552R_MAX_RANGES 5
#define AD3542R_MAX_RANGES 6
--
2.45.0.rc1
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