On Fri, 21 Mar 2025 21:28:48 +0100 Angelo Dureghello <adureghello@xxxxxxxxxxxx> wrote: > From: Angelo Dureghello <adureghello@xxxxxxxxxxxx> > > Add documentation for ad3552r driver, needed to describe the high-speed > driver debugfs attributes and shows how the user may use them. > > Signed-off-by: Angelo Dureghello <adureghello@xxxxxxxxxxxx> > --- > Documentation/iio/ad3552r.rst | 65 +++++++++++++++++++++++++++++++++++++++++++ > Documentation/iio/index.rst | 1 + > MAINTAINERS | 1 + > 3 files changed, 67 insertions(+) > > diff --git a/Documentation/iio/ad3552r.rst b/Documentation/iio/ad3552r.rst > new file mode 100644 > index 0000000000000000000000000000000000000000..638a62c99fb876cca026a0b1df469c81ba39ff29 > --- /dev/null > +++ b/Documentation/iio/ad3552r.rst > @@ -0,0 +1,65 @@ > +.. SPDX-License-Identifier: GPL-2.0-only > + > +============== > +AD3552R driver > +============== > + > +Device driver for Analog Devices Inc. AD35XXR series of DACs. The module name > +is ``ad3552r``. > +With the same module name, two different driver variants are available, the > +``generic spi`` variant, to be used with any classic SPI controllers, and the > +``hs`` (high speed) variant, for an ADI ``axi-dac`` (IP core) based controller > +that allows to reach the maximum sample rate supported from the DACs, using the > +DMA transfer and all the SPI lines available (D/QDSPI).. > +The high speed driver variant is intended to be used with the ``adi-axi-dac`` > +backend support enabled, that is enabled by default when the driver is selected. > + > +Supported devices > +================= > + > +* `AD3541R <https://www.analog.com/en/products/ad3541r.html>`_ > +* `AD3542R <https://www.analog.com/en/products/ad3542r.html>`_ > +* `AD3551R <https://www.analog.com/en/products/ad3551r.html>`_ > +* `AD3552R <https://www.analog.com/en/products/ad3552r.html>`_ > + > +Wiring connections > +------------------ > + > +:: > + > + .-----------------. .-------. > + | |--- D/QSPI -----| | > + | DAC IP CORE |--- SPI S_CLK --| DAC | > + | |--- SPI CS -----| | > + | |--- LDAC -------| | > + | |--- RESET ------| | > + |_________________| |_______| > + > + > +High speed features > +=================== > + > +Device attributes > +----------------- > + > +The following table shows the ad35xxr related device debug files, found in the > +specific device debug folder path ``/sys/kernel/debug/iio/iio:deviceX``. > + > ++----------------------+-------------------------------------------------------+ > +| Debugfs device files | Description | > ++----------------------+-------------------------------------------------------+ > +| data_source | The used data source, | > +| | as ``iio-buffer`` or ``backend-ramp-generator``. | > ++----------------------+-------------------------------------------------------+ Hmm. I'm not convinced yet that this is something that belongs in debugfs but will read on through the series. > + > +Usage examples > +-------------- > + > +. code-block:: bash > + root:/sys/bus/iio/devices/iio:device0# cat data_source > + iio-buffer > + root:/sys/bus/iio/devices/iio:device0# echo -n backend-ramp-generator > data_source > + root:/sys/bus/iio/devices/iio:device0# cat data_source⏎ Not sure what the trailing character is. > + backend-ramp-generator > + > + > diff --git a/Documentation/iio/index.rst b/Documentation/iio/index.rst > index bbb2edce8272e7483acca500d1a757bbcc11c1e0..2d6afc5a8ed54a90cd8d5723f0dc5212b8593d16 100644 > --- a/Documentation/iio/index.rst > +++ b/Documentation/iio/index.rst > @@ -19,6 +19,7 @@ Industrial I/O Kernel Drivers > .. toctree:: > :maxdepth: 1 > > + ad3552r > ad4000 > ad4030 > ad4695 > diff --git a/MAINTAINERS b/MAINTAINERS > index 57eaab00f6cb53df52a4799eb2c1afbbd1e77a1e..52bc56a9ee22c66b90555681c4757ea4399adae1 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -1295,6 +1295,7 @@ L: linux-iio@xxxxxxxxxxxxxxx > S: Supported > W: https://ez.analog.com/linux-software-drivers > F: Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml > +F: Documentation/iio/ad3552r.rst > F: drivers/iio/dac/ad3552r.c > > ANALOG DEVICES INC AD4000 DRIVER >
