[PATCH 1/2] spi: Add a DT binding for high-impedance turn-around
STALE2926d
From: Linus Walleij <hidden>
Date: 2018-09-25 20:40:15
Subsystem:
open firmware and flattened device tree bindings, spi subsystem, the rest · Maintainers:
Rob Herring, Krzysztof Kozlowski, Conor Dooley, Mark Brown, Linus Torvalds
Some 3WIRE SPI devices require the host to insert a "high-impedance turn-around" essentially a clock pulse after switching the one line from output to input. This is needed to support the TPO TPG110 panel to use the 3WIRE SPI bindings. Cc: devicetree@vger.kernel.org Cc: Andrzej Hajda <redacted> Cc: Lorenzo Bianconi <redacted> Signed-off-by: Linus Walleij <redacted> --- ChangeLog v1->v2: - Change some spelling, instert dash in high-impedance use turn-around instead of turnaround. --- Documentation/devicetree/bindings/spi/spi-bus.txt | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt
index 1f6e86f787ef..d0b2d88a20ee 100644
--- a/Documentation/devicetree/bindings/spi/spi-bus.txt
+++ b/Documentation/devicetree/bindings/spi/spi-bus.txt@@ -70,6 +70,10 @@ All slave nodes can contain the following optional properties: - spi-cs-high - Empty property indicating device requires chip select active high. - spi-3wire - Empty property indicating device requires 3-wire mode. +- spi-3wire-high-impedance-turn-around - Empty property indicating that a + 3wire host need to insert a high-impedance turn-around + clock cycle after turning the one output line into an + input line. - spi-lsb-first - Empty property indicating device requires LSB first mode. - spi-tx-bus-width - The bus width (number of data wires) that is used for MOSI. Defaults to 1 if not present.
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2.17.1