| Message ID | 20170125202810.16876-3-chris.brandt@renesas.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jan 25, 2017 at 03:28:09PM -0500, Chris Brandt wrote: > In the case of a single clock source, you don't need names. However, > if the controller has 2 clock sources, you need to name them correctly > so the driver can find the 2nd one. The 2nd clock is for the internal > card detect logic. > > Signed-off-by: Chris Brandt <chris.brandt@renesas.com> > Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> > --- > v5: > * add Reviewed-by: Geert Uytterhoeven > * list number of clocks for each SoC > * remove example because it already exists in mmc.txt > v4: > * just explain there might be 2 clocks, don't explain how > we will use them in the driver > v3: > * add more clarification about why there are sometimes 2 clocks > and what you should do with them. > * remove 'status = "disabled"' from example > v2: > * fix spelling and change wording > * changed clock name from "carddetect" to "cd" > --- > Documentation/devicetree/bindings/mmc/tmio_mmc.txt | 13 +++++++++++++ > 1 file changed, 13 insertions(+) Acked-by: Rob Herring <robh@kernel.org> -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/mmc/tmio_mmc.txt b/Documentation/devicetree/bindings/mmc/tmio_mmc.txt index a1650ed..4fd8b7a 100644 --- a/Documentation/devicetree/bindings/mmc/tmio_mmc.txt +++ b/Documentation/devicetree/bindings/mmc/tmio_mmc.txt @@ -25,6 +25,19 @@ Required properties: "renesas,sdhi-r8a7795" - SDHI IP on R8A7795 SoC "renesas,sdhi-r8a7796" - SDHI IP on R8A7796 SoC +- clocks: Most controllers only have 1 clock source per channel. However, on + some variations of this controller, the internal card detection + logic that exists in this controller is sectioned off to be run by a + separate second clock source to allow the main core clock to be turned + off to save power. + If 2 clocks are specified by the hardware, you must name them as + "core" and "cd". If the controller only has 1 clock, naming is not + required. + Below is the number clocks for each supported SoC: + 1: SH73A0, R8A73A4, R8A7740, R8A7778, R8A7779, R8A7790 + R8A7791, R8A7792, R8A7793, R8A7794, R8A7795, R8A7796 + 2: R7S72100 + Optional properties: - toshiba,mmc-wrprotect-disable: write-protect detection is unavailable - pinctrl-names: should be "default", "state_uhs"