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e253d2c551
Most of the descriptions here are oriented to a Kernel developer. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
35 lines
1.3 KiB
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35 lines
1.3 KiB
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============================================================================
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Kernel driver for the NXP Semiconductors PN544 Near Field Communication chip
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============================================================================
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General
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-------
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The PN544 is an integrated transmission module for contactless
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communication. The driver goes under drives/nfc/ and is compiled as a
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module named "pn544".
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Host Interfaces: I2C, SPI and HSU, this driver supports currently only I2C.
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Protocols
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---------
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In the normal (HCI) mode and in the firmware update mode read and
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write functions behave a bit differently because the message formats
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or the protocols are different.
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In the normal (HCI) mode the protocol used is derived from the ETSI
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HCI specification. The firmware is updated using a specific protocol,
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which is different from HCI.
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HCI messages consist of an eight bit header and the message body. The
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header contains the message length. Maximum size for an HCI message is
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33. In HCI mode sent messages are tested for a correct
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checksum. Firmware update messages have the length in the second (MSB)
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and third (LSB) bytes of the message. The maximum FW message length is
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1024 bytes.
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For the ETSI HCI specification see
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http://www.etsi.org/WebSite/Technologies/ProtocolSpecification.aspx
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