From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- Documentation/driver-api/nfc/nfc-pn544.rst | 34 ++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 Documentation/driver-api/nfc/nfc-pn544.rst (limited to 'Documentation/driver-api/nfc/nfc-pn544.rst') diff --git a/Documentation/driver-api/nfc/nfc-pn544.rst b/Documentation/driver-api/nfc/nfc-pn544.rst new file mode 100644 index 0000000000..6b2d8aae0c --- /dev/null +++ b/Documentation/driver-api/nfc/nfc-pn544.rst @@ -0,0 +1,34 @@ +============================================================================ +Kernel driver for the NXP Semiconductors PN544 Near Field Communication chip +============================================================================ + + +General +------- + +The PN544 is an integrated transmission module for contactless +communication. The driver goes under drives/nfc/ and is compiled as a +module named "pn544". + +Host Interfaces: I2C, SPI and HSU, this driver supports currently only I2C. + +Protocols +--------- + +In the normal (HCI) mode and in the firmware update mode read and +write functions behave a bit differently because the message formats +or the protocols are different. + +In the normal (HCI) mode the protocol used is derived from the ETSI +HCI specification. The firmware is updated using a specific protocol, +which is different from HCI. + +HCI messages consist of an eight bit header and the message body. The +header contains the message length. Maximum size for an HCI message is +33. In HCI mode sent messages are tested for a correct +checksum. Firmware update messages have the length in the second (MSB) +and third (LSB) bytes of the message. The maximum FW message length is +1024 bytes. + +For the ETSI HCI specification see +http://www.etsi.org/WebSite/Technologies/ProtocolSpecification.aspx -- cgit v1.2.3