Supported secure elements are typically found during a discovery process
initiated when the NFC controller is up and running. For a given NFC
chipset there can be many configurations (embedded SE or not, with or
without a SIM card wired to the NFC controller SWP interface, etc...) and
thus driver code will never know before hand which SEs are available.
So we remove this field, it will be replaced by a real SE discovery
mechanism.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Before any operation, driver interruption is de-asserted to prevent
race condition between TX and RX.
Transaction starts by emitting "Direct read" and acknowledged mode
bytes. Then packet length is read allowing to allocate correct NCI
socket buffer. After that payload is retrieved.
A delay after the transaction can be added.
This delay is determined by the driver during nci_spi_allocate_device()
call and can be 0.
If acknowledged mode is set:
- CRC of header and payload is checked
- if frame reception fails (CRC error): NACK is sent
- if received frame has ACK or NACK flag: unblock nci_spi_send()
Payload is passed to NCI module.
At the end, driver interruption is re asserted.
Signed-off-by: Frederic Danis <frederic.danis@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Before any operation, driver interruption is de-asserted to prevent
race condition between TX and RX.
The NCI over SPI header is added in front of NCI packet.
If acknowledged mode is set, CRC-16-CCITT is added to the packet.
Then the packet is forwarded to SPI module to be sent.
A delay after the transaction is added.
This delay is determined by the driver during nci_spi_allocate_device()
call and can be 0.
After data has been sent, driver interruption is re-asserted.
If acknowledged mode is set, nci_spi_send will block until
acknowledgment is received.
Signed-off-by: Frederic Danis <frederic.danis@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The NFC Forum defines a transport interface based on
Serial Peripheral Interface (SPI) for the NFC Controller
Interface (NCI).
This module implements the SPI transport of NCI, calling SPI module
directly to read/write data to NFC controller (NFCC).
NFCC driver should provide functions performing device open and close.
It should also provide functions asserting/de-asserting interruption
to prevent TX/RX race conditions.
NFCC driver can also fix a delay between transactions if needed by
the hardware.
Signed-off-by: Frederic Danis <frederic.danis@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>