This version (05 Apr 2024 13:03) is a draft.
Approvals: 0/1The Previously approved version (06 Feb 2021 00:00) is available.
Approvals: 0/1The Previously approved version (06 Feb 2021 00:00) is available.
Table of Contents
AD8460 IIO DAC Linux Driver
Supported Devices
Evaluation Boards
Description
This is a Linux industrial I/O (IIO) subsystem driver, targeting single channel DAC. 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.
See IIO for more information.
Source Code
Status
| Source | Mainlined? |
|---|---|
| git | [No] |
Files
| Function | File |
|---|---|
| driver | drivers/iio/dac/ad8460.c |
| include | include/dt-bindings/iio/adi,ad8460.h |
| Documentation | Documentation/devicetree/bindings/iio/dac/ad8460.txt |
Hardware configuration
Device tree example
The following example instantiates the ad8460 driver for an AD8460 device connected on the SPI bus to the chip-select line 0.
#include <dt-bindings/iio/adi,ad8460.h>
#include "zynq-zed.dtsi"
#include "zynq-zed-adv7511.dtsi"
/ {
clocks {
sync_ext_clk: ext-clk {
#clock-cells = <0x0>;
compatible = "fixed-clock";
clock-frequency = <500000>;
clock-output-names = "sync_ext_clk";
};
};
};
&fpga_axi {
tx_dma: tx_dmac@44000000 {
compatible = "adi,axi-dmac-1.00.a";
reg = <0x44000000 0x1000>;
interrupts = <0 57 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clkc 15>;
#dma-cells = <1>;
adi,channels {
#size-cells = <0>;
#address-cells = <1>;
dma-channel@0 {
reg = <0>;
adi,source-bus-width = <64>;
adi,source-bus-type = <0>;
adi,destination-bus-width = <32>;
adi,destination-bus-type = <2>;
adi,cyclic;
};
};
};
};
&spi0 {
status = "okay";
ad8460: dac@0 {
compatible = "adi,ad8460";
reg = <0>;
spi-max-frequency = <8000000>;
adi,rset-ohms = <2000>;
adi,ilim-microamp = <100000 100000>;
adi,vlim-microvolt = <(-40000000) 40000000>;
adi,temp-lim-millicelsius = <40000>;
clocks = <&sync_ext_clk>;
clock-names = "sync_clk";
dma-names = "tx";
dmas = <&tx_dma 0>;
};
};
Driver testing
If the driver correctly detected the device, the “iio_info” program should inform us about the available channels:
root@linaro-ubuntu-desktop:~# iio_info
Library version: 0.24 (git tag: accb7b5)
Compiled with backends: local xml ip usb serial
IIO context created with local backend.
Backend version: 0.24 (git tag: accb7b5)
Backend description string: Linux analog 6.1.0-271638-g3dfbf1932ce9-dirty #348 SMP PREEMPT Fri Apr 5 16:48:16 CST 2024 armv7l
IIO context has 9 attributes:
hdl_system_id: [ad8460] on [zed] git branch [master] git [ea29a37eae8a1daeaadb79281b3085709aaedb1c] clean [2024-01-29 03:51:24] UTC
hw_model: AD8460-FMC-EVAL-BZ on Xilinx Zynq ZED
hw_carrier: Xilinx Zynq ZED
hw_mezzanine: AD8460-FMC-EVAL-BZ
hw_name: AD8460-EVAL-RevB
hw_vendor: Analog Devices
hw_serial: AD8460-FMC-EVAL-BZ
local,kernel: 6.1.0-271638-g3dfbf1932ce9-dirty
uri: local:
IIO context has 4 devices:
hwmon0: e000b000ethernetffffffff00
1 channels found:
temp1: (input)
3 channel-specific attributes found:
attr 0: crit value: 100000
attr 1: input value: 16000
attr 2: max_alarm value: 0
No trigger on this device
iio:device0: xadc
9 channels found:
voltage5: vccoddr (input)
3 channel-specific attributes found:
attr 0: label value: vccoddr
attr 1: raw value: 2048
attr 2: scale value: 0.732421875
voltage0: vccint (input)
3 channel-specific attributes found:
attr 0: label value: vccint
attr 1: raw value: 1382
attr 2: scale value: 0.732421875
voltage4: vccpaux (input)
3 channel-specific attributes found:
attr 0: label value: vccpaux
attr 1: raw value: 2454
attr 2: scale value: 0.732421875
temp0: (input)
3 channel-specific attributes found:
attr 0: offset value: -2219
attr 1: raw value: 2534
attr 2: scale value: 123.040771484
voltage7: vrefn (input)
3 channel-specific attributes found:
attr 0: label value: vrefn
attr 1: raw value: -4
attr 2: scale value: 0.732421875
voltage1: vccaux (input)
3 channel-specific attributes found:
attr 0: label value: vccaux
attr 1: raw value: 2452
attr 2: scale value: 0.732421875
voltage2: vccbram (input)
3 channel-specific attributes found:
attr 0: label value: vccbram
attr 1: raw value: 1381
attr 2: scale value: 0.732421875
voltage3: vccpint (input)
3 channel-specific attributes found:
attr 0: label value: vccpint
attr 1: raw value: 1376
attr 2: scale value: 0.732421875
voltage6: vrefp (input)
3 channel-specific attributes found:
attr 0: label value: vrefp
attr 1: raw value: 1702
attr 2: scale value: 0.732421875
2 device-specific attributes found:
attr 0: sampling_frequency value: 961538
attr 1: waiting_for_supplier value: 0
No trigger on this device
iio:device1: ad8460
1 channels found:
altvoltage0: (output)
2 channel-specific attributes found:
attr 0: powerdown value: 0
attr 1: sampling_frequency value: 500000
2 device-specific attributes found:
attr 0: scale value: 80
attr 1: waiting_for_supplier value: 0
5 debug attributes found:
debug attr 0: apg_pattern_memory value: 0 0x2000
debug attr 1: shutdown_flag value: 0
debug attr 2: apg_pattern_depth value: 3
debug attr 3: apg_mode_enable value: 0
debug attr 4: direct_reg_access value: 0x10
No trigger on this device
iio_sysfs_trigger:
0 channels found:
2 device-specific attributes found:
attr 0: add_trigger ERROR: Permission denied (13)
attr 1: remove_trigger ERROR: Permission denied (13)
No trigger on this device
playground/playground.txt · Last modified: 05 Apr 2024 13:03 by Tinaco Mariel