Add fallback compatibility strings for R-Car Gen 1, 2 and 3 to the SDHI
bindings and driver.
In the case of Renesas R-Car hardware we know that there are generations of
SoCs, f.e. Gen 1 and 2. But beyond that its not clear what the relationship
between IP blocks might be. For example, I believe that r8a7790 is older
than r8a7791 but that doesn't imply that the latter is a descendant of the
former or vice versa.
We can, however, by examining the documentation and behaviour of the
hardware at run-time observe that the current driver implementation appears
to be compatible with the IP blocks on SoCs within a given generation.
For the above reasons and convenience when enabling new SoCs a
per-generation fallback compatibility string scheme being adopted for
drivers for Renesas SoCs.
Based on mmc/next
Changes since v2:
* Update example to current upstream using newer CPG/MSSR bindings
Changes since v1:
* Describe example in patch one as being for the r8a7790 (R-Car H2) rather
than the r8a7779 (R-Car H1)
* Accumulate review tags from Geert Uytterhoeven
Simon Horman (3):
dt-bindings: mmc: renesas_sdhi: provide example in bindings
documentation
dt-bindings: mmc: renesas_sdhi: add R-Car Gen[123] fallback
compatibility strings
mmc: renesas_sdhi: implement R-Car Gen[123] fallback compatibility
strings
Documentation/devicetree/bindings/mmc/tmio_mmc.txt | 70 +++++++++++++++++++++-
drivers/mmc/host/renesas_sdhi_internal_dmac.c | 1 +
drivers/mmc/host/renesas_sdhi_sys_dmac.c | 5 +-
3 files changed, 74 insertions(+), 2 deletions(-)
--
2.11.0
