[PATCH 1/4] devicetree: bindings: pci: document tx-deempth tx swing and rx-eq property

[Ansuel Smith]

Document tx-deempth, tx swing and rx-eq property property used on some
device (qcom ipq806x or imx6q) to tune and fix init error of the pci
bridge.

Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
---
 Documentation/devicetree/bindings/pci/pci.txt | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/pci.txt b/Documentation/devicetree/bindings/pci/pci.txt
index 29bcbd88f457..df37486f1853 100644
--- a/Documentation/devicetree/bindings/pci/pci.txt
+++ b/Documentation/devicetree/bindings/pci/pci.txt
@@ -24,6 +24,24 @@ driver implementation may support the following properties:
    unsupported link speed, for instance, trying to do training for
    unsupported link speed, etc.  Must be '4' for gen4, '3' for gen3, '2'
    for gen2, and '1' for gen1. Any other values are invalid.
+- tx-deemph-gen1
+   If present this property will tune the Transmit De-Emphasis level for GEN1 if
+   supported by the driver.
+- tx-deemph-gen2-3p5db
+   If present this property will tune the Transmit De-Emphasis level for GEN2 in
+   3.5db band if supported by the driver.
+- tx-deempth-gen2-6db
+   If present this property will tune the Transmit De-Emphasis level for GEN2 in
+   6db band if supported by the driver.
+- tx-swing-full
+   If present this property will tune the Tx Swing Full value if supported by the
+   driver.
+- tx-swing-low
+   If present this property will tune the Tx Swing Low value if supported by the
+   driver.
+- rx-equalization
+   If present this property will tune the Rx equalization value if supported by
+   the driver.
 - reset-gpios:
    If present this property specifies PERST# GPIO. Host drivers can parse the
    GPIO and apply fundamental reset to endpoints.
-- 
2.25.1