The driver spi-rockchip does not support spi slave mode, but the register map has an entry indicate that the chip support it. An example implementation found here: https://dev.t-firefly.com/thread-101485-1-1.html The patch is my first approach to support slave mode which is needed in one of our projects, the PCBA is not yet available but we think to have it for testing very soon. Yes, the code in the patch isn't tested yet. I found it odd, that the num_chipselect is set fixed to the amount of native chip-select lines rather use the max_native_cs. Changed it. - master->num_chipselect = ROCKCHIP_SPI_MAX_CS_NUM; + of_property_read_u32(np, "num-cs", &num_cs); + master->num_chipselect = num_cs; + master->max_native_cs = ROCKCHIP_SPI_MAX_CS_NUM; That ask to enable cs_gpiods, and support gpio cs + master->use_gpio_descriptors = true; Patch against next-20200505 Thanks for review! Happy hacking Chris Signed-off-by: Chris Ruehl <chris.ruehl@xxxxxxxxxxxx> --- _______________________________________________ Linux-rockchip mailing list Linux-rockchip@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/linux-rockchip
