The
magma driver provides an interface to Magma LC2+1Sp, 2+1Sp, 4+1Sp, 8+2Sp, 4Sp, 8Sp, 12Sp, 16Sp, 1P and 2P boards. These boards are based around the Cirrus Logic CD1400 serial/parallel communications engine and the Cirrus Logic CD1190 parallel communications engine.
The device minor numbers for this driver are encoded as follows:
+---+---+---+---+---+---+---+---+
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
+---+---+---+---+---+---+---+---+
| | | | | | | |
| | | | +---+---+---+---> port number
| | | |
| | | +-------------------> dial-out (on tty ports)
| | |
| | +-----------------------> unused
| |
+---+---------------------------> card number
Up to four cards are supported in the system.
All tty ports have full automatic hardware (RTS/CTS) flow control available and a 12 byte FIFO on the chip in each direction so errors should be minimal.