Support GPIO for SPI Chip Selection?

[Qingwu-Li]

Possible to support an/several GPIO for SPI Chip Selection?

[vsergeev]

This could be supported relatively easily by passing a GPIO object as a cs_gpio keyword argument in the SPI constructor. The SPI object would assert and deassert the chip select in transfer(). Inverted / non-inverted would be up to the GPIO.