blob: 556fa877f2e816a143113b880db1cf1c727285be (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
|
SPI Chip Select behavior:
With the Blackfin on-chip SPI peripheral, there is some logic tied to the CPHA
bit whether the Slave Select Line is controlled by hardware (CPHA=0) or
controlled by software (CPHA=1). However, the Linux SPI bus driver assumes that
the Slave Select is always under software control and being asserted during
the entire SPI transfer. - And not just bits_per_word duration.
In most cases you can utilize SPI MODE_3 instead of MODE_0 to work-around this
behavior. If your SPI slave device in question requires SPI MODE_0 or MODE_2
timing, you can utilize the GPIO controlled SPI Slave Select option instead.
You can even use the same pin whose peripheral role is a SSEL,
but use it as a GPIO instead.
|
