From 837eb4d21ecde7bde7a1fe523594fdf509055f3f Mon Sep 17 00:00:00 2001 From: Geoff Lansberry Date: Wed, 21 Dec 2016 23:18:32 -0500 Subject: NFC: trf7970a: add device tree option for 27MHz clock The TRF7970A has configuration options to support hardware designs which use a 27.12MHz clock. This commit adds a device tree option 'clock-frequency' to support configuring the this chip for default 13.56MHz clock or the optional 27.12MHz clock. Acked-by: Rob Herring Acked-by: Mark Greer Signed-off-by: Geoff Lansberry Signed-off-by: Samuel Ortiz --- Documentation/devicetree/bindings/net/nfc/trf7970a.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt index 5889a3d133b2..1d186cd9817b 100644 --- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt +++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt @@ -21,6 +21,7 @@ Optional SoC Specific Properties: - t5t-rmb-extra-byte-quirk: Specify that the trf7970a has the erratum where an extra byte is returned by Read Multiple Block commands issued to Type 5 tags. +- clock-frequency: Set to specify that the input frequency to the trf7970a is 13560000Hz or 27120000Hz Example (for ARM-based BeagleBone with TRF7970A on SPI1): @@ -43,6 +44,7 @@ Example (for ARM-based BeagleBone with TRF7970A on SPI1): irq-status-read-quirk; en2-rf-quirk; t5t-rmb-extra-byte-quirk; + clock-frequency = <27120000>; status = "okay"; }; }; -- cgit v1.2.3