It has become necessary to distinguish between the various DPFE API versions by version number. Having just chip-specific compatible strings and one generic version is no longer meeting our needs. Also, a new DPFE API version, v4, needs to be supported by the driver. As a result, an intermediate compatible string format is being introduced: brcm,dpfe-cpu-v<N> where <N> represents the API version number. This is more specific than the catch-all "brcm,dpfe-cpu" and more generic than chip-specific compatible strings, such as "brcm,bcm7271-dpfe-cpu". The changes are split into several steps. First, we update the binding and introduce the versioned compatible strings. Secondly, we add support for brcm,dpfe-cpu-v1 through brcm,dpfe-cpu-v3 in the driver to match existing API versions. Thirdly, we introduce DPFE API v4. Lastly, there is a change that isn't directly related to the introduction of the new binding format or DPFE API v4. However, with the increasing number of API versions, broadening compatibility can be helpful. If registering the driver using the DT-provided compatible string fails, the driver will try all DPFE APIs (except for v1) to see if one might end up working. This can come in handy if the driver moves on and learns about new API versions while Device Tree cannot be updated. Markus Mayer (4): dt-bindings: memory: additional compatible strings for Broadcom DPFE memory: brcmstb_dpfe: introduce version-specific compatible strings memory: brcmstb_dpfe: support DPFE API v4 memory: brcmstb_dpfe: introduce best-effort API detection .../memory-controllers/brcm,dpfe-cpu.yaml | 8 +- drivers/memory/brcmstb_dpfe.c | 95 ++++++++++++++++++- 2 files changed, 100 insertions(+), 3 deletions(-) -- 2.43.0
