• Frieder Schrempf's avatar
    dt-bindings: spi: Adjust the bindings for the FSL QSPI driver · 78df3080
    Frieder Schrempf authored
    Adjust the documentation of the new SPI memory interface based
    driver to reflect the new drivers settings.
    
    The "old" driver was using the "fsl,qspi-has-second-chip" property to
    select one of two dual chip setups (two chips on one bus or two chips
    on separate buses). And it used the order in which the subnodes are
    defined in the dt to select the CS, the chip is connected to.
    
    Both methods are wrong and in fact the "reg" property should be used to
    determine which bus and CS a chip is connected to. This also enables us
    to use different setups than just single chip, or symmetric dual chip.
    
    So the porting of the driver from the MTD to the SPI framework actually
    enforces the use of the "reg" properties and makes
    "fsl,qspi-has-second-chip" superfluous.
    
    As all boards that have "fsl,qspi-has-second-chip" set, also have
    correct "reg" properties, the removal of this property shouldn't lead to
    any incompatibilities.
    
    The only compatibility issues I can see are with imx6sx-sdb.dts and
    imx6sx-sdb-reva.dts, which have their reg properties set incorrectly
    (see explanation here: [2]), all other boards should stay compatible.
    
    Also the "big-endian" flag was removed, as this setting is now selected
    by the driver, depending on which SoC is in use.
    
    [2] https://patchwork.ozlabs.org/patch/922817/#1925445Signed-off-by: default avatarFrieder Schrempf <frieder.schrempf@kontron.de>
    Reviewed-by: default avatarRob Herring <robh@kernel.org>
    Signed-off-by: default avatarMark Brown <broonie@kernel.org>
    78df3080
spi-fsl-qspi.txt 1.75 KB