Commits
Leilk Liu committed 37457607eca
spi: mediatek: mt8173 spi multiple devices support mt8173 IC spi HW has 4 gpio group, it's possible to support max <= 4 slave devices, even mtk spi HW is not congruent to spi core. 1. When a device do a spi_message transfer, spi HW should know which pad-group this device is on, and then writes pad-select register. 2. Mtk pad-select register just selects which MISO pin HW will receive data. For example, pad-select=1(select spi1 pins), HW just receives data from spi1 MISO, but it still send waveform to all 4 group cs/clk/mosi. If cs pin in other groups is still spi mode, after spi1 is selected(by active cs pin), devices on other group will also be selected. Signed-off-by: Leilk Liu <leilk.liu@mediatek.com> Signed-off-by: Mark Brown <broonie@kernel.org>