Some Renesas SoC based boards mux SD and eMMC on a single sdio
controller, exposing user control by dip switch and software control by
gpio.

Purpose is to simplify development and provisioning by selecting boot
media at power-on, and again before starting linux.

Add binding and driver support for linking a (gpio) mux to renesas sdio
controller.

Introduce generic helper functions for getting managed and selected
mux-state objects, and switch i2c-omap and phy-can-transceiver drivers.

Signed-off-by: Josua Mayer <josua@solid-run.com>
---
Changes in v3:
- updated omap-i2c and phy-can-transceiver to use new helpers.
- created generic helper functions for getting managed optional mux-state.
  (Reported-by: Rob Herring <robh@kernel.org>)
- picked up binding ack by Rob Herring.
- replaced use of "SDIO" with "SD/SDIO/eMMC" in binding document and
  commit descriptions.
  (Reported-by: Ulf Hansson <ulf.hansson@linaro.org>)
- Link to v2: https://lore.kernel.org/r/20251201-rz-sdio-mux-v2-0-bcb581b88dd7@solid-run.com

Changes in v2:
- dropped mux-controller node from dt binding example
  (Reported-by: Conor Dooley <conor@kernel.org>
   Reported-by: Krzysztof Kozlowski <krzk@kernel.org>)
- Link to v1: https://lore.kernel.org/r/20251128-rz-sdio-mux-v1-0-1ede318d160f@solid-run.com

---
Josua Mayer (6):
      phy: can-transceiver: rename temporary helper function to avoid conflict
      mux: Add helper functions for getting optional and selected mux-state
      phy: can-transceiver: drop temporary helper getting optional mux-state
      i2c: omap: switch to new generic helper for getting selected mux-state
      dt-bindings: mmc: renesas,sdhi: Add mux-states property
      mmc: host: renesas_sdhi_core: support selecting an optional mux

 .../devicetree/bindings/mmc/renesas,sdhi.yaml      |  6 ++
 drivers/i2c/busses/i2c-omap.c                      | 19 ++----
 drivers/mmc/host/Kconfig                           |  1 +
 drivers/mmc/host/renesas_sdhi.h                    |  1 +
 drivers/mmc/host/renesas_sdhi_core.c               | 16 +++++-
 drivers/mux/core.c                                 | 67 +++++++++++++++++++---
 drivers/phy/phy-can-transceiver.c                  | 10 ----
 include/linux/mux/consumer.h                       |  4 ++
 8 files changed, 89 insertions(+), 35 deletions(-)
---
base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
change-id: 20251128-rz-sdio-mux-acc5137f1618

Best regards,
-- 
Josua Mayer <josua@solid-run.com>