On Thu, Nov 28, 2024 at 01:20:09AM +0900, Hector Martin wrote: > > > On 2024/11/28 0:29, Hector Martin wrote: > > > > > > On 2024/11/27 17:29, Sasha Finkelstein wrote: > >> On Wed, 27 Nov 2024 at 02:51, Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> wrote: > >>> I believe this needs to be done at the SPI controller level. See > >>> "cs-gpiods" property in > >>> Documentation/devicetree/bindings/spi/spi-controller.yaml that, as far > >>> as I understand, allows overriding controller's native CS handling with > >>> a GPIO when needed. > >> > >> I have already tried doing that (adding the relevant gpio as cs-gpios > >> on the controller) > >> and for some reason none of my attempts worked. Since there is no hardware > >> documentation, I can't really tell why, could be possible that we need both > >> native CS and that gpio, could be memory barrier issues somewhere in > >> the driver core, > >> but the method above is the only one i could get to work. > > > > Are you sure this isn't just a pinmux problem, i.e. the bootloader > > initializes the pinmux for hardware CS only on one device and not the other? > > > > See spi3_pins in the DTS in our downstream tree (and the reference from > > the SPI controller). If the rest of the SPI pins are already working > > properly you can just try with the CS pin (same index as on the gpio > > spec). Ideally we'd list the 4 pins, but someone needs to reverse > > engineer the mapping with m1n1 gpiola since we don't know what it is. > > > > If it really doesn't work with native CS and proper pinmux then cs-gpios > > on the controller should work. If it doesn't something weird is going on > > elsewhere. There's only one CS line, needing both makes no sense. > > > > Looked into this. The pins are 67=CLK, 68=MOSI, 69=MISO for spi0 on > t8103 (they should be added to pinctrl even though they are already > configured by iBoot, ping Janne). queued for the next revision of my "Add Apple SPI controller and spi-nor dt nodes" series [0] and imported in the downstream kernel. thanks Janne [0] https://lore.kernel.org/asahi/20241127-asahi-spi-dt-v1-0-907c9447f623@xxxxxxxxxx/
