Support for Dual SPI and Quad SPI was added to the Linux driver in
commit 0605d9fb41 ("spi: sun6i: add quirk for dual and quad SPI modes
support") and commit 25453d797d ("spi: sun6i: add dual and quad SPI
modes support for R329/D1/R528/T113s").
However the binding was never updated to allow these modes. Allow them
by adding 2 and 4 to the allowed bus widths for the newer variants.
While at it, also add 0 to the allowed bus widths. This signals that
RX or TX is not available, i.e. the MISO or MOSI pin is disconnected.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Chen-Yu Tsai <wens@kernel.org>
Link: https://patch.msgid.link/20260302153559.3199783-2-wens@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Merge series from David Lechner <dlechner@baylibre.com>:
This series is adding support for SPI controllers and peripherals that
have multiple SPI data lanes (data lanes being independent sets of
SDI/SDO lines, each with their own serializer/deserializer).
This series covers this specific use case:
+--------------+ +---------+
| SPI | | SPI |
| Controller | | ADC |
| | | |
| CS0 |--->| CS |
| SCLK |--->| SCLK |
| SDO |--->| SDI |
| SDI0 |<---| SDOA |
| SDI1 |<---| SDOB |
| SDI2 |<---| SDOC |
| SDI3 |<---| SDOD |
+--------------+ +--------+
The ADC is a simultaneous sampling ADC that can convert 4 samples at the
same time. It has 4 data output lines (SDOA-D) that each contain the
data of one of the 4 channels. So it requires a SPI controller with 4
separate deserializers in order to receive all of the information at the
same time.
This should also work for the use case in [1] as well. (Some of the
patches in this series were already submitted there). In that case the
SPI controller is used kind of like it is two separate SPI controllers,
each with its own chip select, clock, and data lines.
[1]: https://lore.kernel.org/linux-spi/20250616220054.3968946-1-sean.anderson@linux.dev/
The DT bindings are a fairly straight-forward mapping of which pins on
the peripheral are connected to which pins on the controller. The SPI
core code parses this and makes the information available to drivers.
When a peripheral driver sees that multiple data lanes are wired up, it
can chose to use them when sending messages.
The SPI message API is a bit higher-level than just specifying the
number of data lines for a SPI transfer though. I did some research on
other SPI controllers that have this feature. They tend to be the kind
meant for connecting to two flash memory chips at the same time but can
be used more generically as well. They generally have the option to
either use one lane at a time (Sean's use case), or can mirror the same
data on multiple lanes (no users of this yet) or can perform striping
of a single data FIFO/DMA stream to/from the two lanes (our use case).
For now, the API assumes that if you want to do mirror/striping, then
you want to use all available data lanes. Otherwise, it just uses the
first data lane for "normal" SPI transfers.
Change spi-rx-bus-width and spi-tx-bus-width properties from single
uint32 values to arrays of uint32 values. This allows describing SPI
peripherals connected to controllers that have multiple data lanes for
receiving or transmitting two or more words in parallel.
Each index in the array corresponds to a physical data lane (one or more
wires depending on the bus width). Additional mapping properties will be
needed in cases where a lane on the controller or peripheral is skipped.
Bindings that make use of this property are updated in the same commit
to avoid validation errors.
The adi,ad4030 binding can now better describe the chips multi-lane
capabilities, so that binding is refined and gets a new example.
Converting from single uint32 to array of uint32 does not break .dts/
.dtb files since there is no difference between specifying a single
uint32 value and an array with a single uint32 value in devicetree.
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/20260123-spi-add-multi-bus-support-v6-1-12af183c06eb@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The A523 has four SPI controllers. One of them supports MIPI DBI mode
in addition to standard SPI.
Compared to older generations, this newer controller now has a combined
counter for the RX FIFO ad buffer levels. In older generations, the
RX buffer level was a separate bitfield in the FIFO status register.
In practice this difference is negligible. The buffer is mostly
invisible to the implementation. If programmed I/O transfers are limited
to the FIFO size, then the contents of the buffer seem to always be
flushed over to the FIFO. For DMA, the DRQ trigger levels are only tied
to the FIFO levels. In all other aspects, the controller is the same as
the one in the R329.
Add new compatible strings for the new controllers.
Signed-off-by: Chen-Yu Tsai <wens@kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Link: https://patch.msgid.link/20251221110513.1850535-2-wens@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The Allwinner H6 SPI controller has advanced features over the H3
version, but remains compatible with it.
Document the usual "specific", "fallback" compatible string pair.
Also add the R40 version while at it.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
While my email address has changed for a while, all the schemas I
contributed still have the old one unfortunately. Update it.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Rob Herring <robh@kernel.org>
