This version is outdated by a newer approved version.
This version (22 May 2023 14:21) was approved by Paul Pop.The Previously approved version (16 May 2023 08:59) is available.
This version (22 May 2023 14:21) was approved by Paul Pop.The Previously approved version (16 May 2023 08:59) is available.This is an old revision of the document!
Table of Contents
AD3552R Dual Channel, 16-Bit, 33 MUPS, Multispan, Multi-IO SPI DAC Linux device driver
The AD3552R is a low drift, dual channel, ultra-fast, 16-bit accuracy, current output digital-to-analog converter (DAC) that can be configured in multiple voltage span ranges. The AD3552R operates with a fixed 2.5 V reference. Each DAC incorporates three drift compensating feedback resistors for the required external transimpedance amplifier (TIA) that scales the output voltage. Offset and gain scaling registers allow for generation of multiple output span ranges, such as 0 V to 2.5 V, 0 V to 5 V, 0 V to 10 V, −5 V to +5 V, and −10 V to +10 V, and custom intermediate ranges with full 16-bit resolution. The DAC can operate in fast mode for maximum speed or precision mode for maximum accuracy.
Supported Devices
Evaluation Boards
Description
This is a Linux industrial I/O (IIO) subsystem driver, targeting RF Transceivers. The industrial I/O subsystem provides a unified framework for drivers for many different types of converters and sensors using a number of different physical interfaces (i2c, spi, etc). See IIO for more information.
Source Code
Status
Files
| Function | File |
|---|---|
| driver | drivers/iio/dac/axi-ad3552r.c |
Example Linux Device-Tree Initialization
Required devicetree properties:
- compatible: Should always be “adi,axi-ad3552r”
- clocks: define reference clock See Documentation/devicetree/bindings/clock/clock-bindings.txt
Optional properties:
- reset-gpios : a GPIO spec for the Reset pin.
Example:
&fpga_axi {
axi_ad3552r: axi-ad3552r@44a74000 {
compatible = "adi,axi-ad3552r";
reg = <0x44a74000 0x1000>;
reset-gpios = <&gpio0 92 GPIO_ACTIVE_LOW>;
clocks = <&ref_clk>;
dmas = <&dac_tx_dma 0>;
dma-names = "tx";
channel@0 {
reg = <0>;
adi,output-range-microvolt = <0 10000000>;
};
channel@1 {
reg = <1>;
custom-output-range-config {
adi,gain-offset = <5>;
adi,gain-scaling-p-inv-log2 = <1>;
adi,gain-scaling-n-inv-log2 = <2>;
adi,rfb-ohms = <1>;
};
};
};
};
| Function | File |
|---|---|
| EVAL-AD3552R Device Tree | zynq-zed-adv7511-axi-ad3552r_evb.dts |
Enabling Linux driver support
Configure kernel with “make menuconfig” (alternatively use “make xconfig” or “make qconfig”)
Adding Linux driver support
Configure kernel with “make menuconfig” (alternatively use “make xconfig” or “make qconfig”)
Linux Kernel Configuration Device Drivers ---> <*> Industrial I/O support ---> --- Industrial I/O support -*- Enable ring buffer support within IIO -*- Industrial I/O lock free software ring -*- Enable triggered sampling support *** Digital to analog converters *** [--snip--] <*> Analog Devices AD3552R DAC driver [--snip--]
Hardware configuration
Driver testing / API
Each and every IIO device, typically a hardware chip, has a device folder under /sys/bus/iio/devices/iio:deviceX. Where X is the IIO index of the device. Under every of these directory folders reside a set of files, depending on the characteristics and features of the hardware device in question. These files are consistently generalized and documented in the IIO ABI documentation. In order to determine which IIO deviceX corresponds to which hardware device, the user can read the name file /sys/bus/iio/devices/iio:deviceX/name. In case the sequence in which the iio device drivers are loaded/registered is constant, the numbering is constant and may be known in advance.
This specifies any shell prompt running on the target
root@analog:/> cd /sys/bus/iio/devices/ root@analog:/sys/bus/iio/device> ls -l iio:device0 -> ../../../devices/soc0/axi/f8007100.adc/iio:device0 iio:device1 -> ../../../devices/soc0/fpga-axi@0/44a74000.axi-ad3552r/iio:device1 iio_sysfs_trigger -> ../../../devices/iio_sysfs_trigger root:/sys/bus/iio/devices> cd iio:device1 root@analog:/sys/bus/iio/devices/iio:device1# ls -l drwxr-xr-x 2 root root 0 May 16 07:42 buffer drwxr-xr-x 2 root root 0 May 15 15:04 buffer0 -r--r--r-- 1 root root 4096 May 16 07:42 dev -rw-r--r-- 1 root root 4096 May 16 07:42 input_source -r--r--r-- 1 root root 4096 May 16 07:42 input_source_available -r--r--r-- 1 root root 4096 May 15 15:04 name lrwxrwxrwx 1 root root 0 May 16 07:42 of_node -> ../../../../../firmware/devicetree/base/fpga-axi@0/axi-ad3552r@44a74000 -rw-r--r-- 1 root root 4096 May 16 07:42 output_range -r--r--r-- 1 root root 4096 May 16 07:42 output_range_available -rw-r--r-- 1 root root 4096 May 16 07:42 out_voltage0_raw -rw-r--r-- 1 root root 4096 May 16 07:42 out_voltage1_raw drwxr-xr-x 2 root root 0 May 15 15:04 power -rw-r--r-- 1 root root 4096 May 16 07:42 sampling_frequency drwxr-xr-x 2 root root 0 May 15 15:04 scan_elements -rw-r--r-- 1 root root 4096 May 16 07:42 stream_status -r--r--r-- 1 root root 4096 May 16 07:42 stream_status_available lrwxrwxrwx 1 root root 0 May 16 07:42 subsystem -> ../../../../../bus/iio -rw-r--r-- 1 root root 4096 May 16 07:42 uevent root:/sys/bus/iio/devices/iio:device1#
Show device name
This specifies any shell prompt running on the target
root:/sys/bus/iio/devices/iio:device1> cat name axi-ad3552r
DAC sampling rate (sampling_frequency)
Read only attribute which returns the DAC sampling rate in Hz.
This specifies any shell prompt running on the target
root@analog:/sys/bus/iio/devices/iio:device1# cat sampling_frequency 16666667 root@analog:/sys/bus/iio/devices/iio:device1# echo 15000000 > sampling_frequency -bash: echo: write error: Invalid argument root@analog:/sys/bus/iio/devices/iio:device1#
More Information
- IIO mailing list: linux [dash] iio [at] vger [dot] kernel [dot] org
resources/tools-software/linux-drivers/iio-dac/axi-ad3552r.1684515182.txt.gz · Last modified: 19 May 2023 18:53 by Marcelo Schmitt