1*4882a593Smuzhiyun============================================================================ 2*4882a593SmuzhiyunKernel driver for the NXP Semiconductors PN544 Near Field Communication chip 3*4882a593Smuzhiyun============================================================================ 4*4882a593Smuzhiyun 5*4882a593Smuzhiyun 6*4882a593SmuzhiyunGeneral 7*4882a593Smuzhiyun------- 8*4882a593Smuzhiyun 9*4882a593SmuzhiyunThe PN544 is an integrated transmission module for contactless 10*4882a593Smuzhiyuncommunication. The driver goes under drives/nfc/ and is compiled as a 11*4882a593Smuzhiyunmodule named "pn544". 12*4882a593Smuzhiyun 13*4882a593SmuzhiyunHost Interfaces: I2C, SPI and HSU, this driver supports currently only I2C. 14*4882a593Smuzhiyun 15*4882a593SmuzhiyunProtocols 16*4882a593Smuzhiyun--------- 17*4882a593Smuzhiyun 18*4882a593SmuzhiyunIn the normal (HCI) mode and in the firmware update mode read and 19*4882a593Smuzhiyunwrite functions behave a bit differently because the message formats 20*4882a593Smuzhiyunor the protocols are different. 21*4882a593Smuzhiyun 22*4882a593SmuzhiyunIn the normal (HCI) mode the protocol used is derived from the ETSI 23*4882a593SmuzhiyunHCI specification. The firmware is updated using a specific protocol, 24*4882a593Smuzhiyunwhich is different from HCI. 25*4882a593Smuzhiyun 26*4882a593SmuzhiyunHCI messages consist of an eight bit header and the message body. The 27*4882a593Smuzhiyunheader contains the message length. Maximum size for an HCI message is 28*4882a593Smuzhiyun33. In HCI mode sent messages are tested for a correct 29*4882a593Smuzhiyunchecksum. Firmware update messages have the length in the second (MSB) 30*4882a593Smuzhiyunand third (LSB) bytes of the message. The maximum FW message length is 31*4882a593Smuzhiyun1024 bytes. 32*4882a593Smuzhiyun 33*4882a593SmuzhiyunFor the ETSI HCI specification see 34*4882a593Smuzhiyunhttp://www.etsi.org/WebSite/Technologies/ProtocolSpecification.aspx 35