Hi, Am Dienstag, den 17.06.2014, 15:25 +0100 schrieb Lee Jones: > FAO DT chaps, > > I'd be interested to hear your opinion about this. any thoughts on this? With the MediaTek Reset Controller series (https://lkml.org/lkml/2014/10/29/1008) another possible use case for this feature came just up. > > For devices which have a complete register for themselves, it is possible to > > place them next to the syscon device with overlapping reg ranges. The same is > > not possible for devices which only occupy bitfields in registers shared with > > other users. > > For devices that are completely controlled by bitfields in the syscon address > > range, such as multiplexers or voltage regulators, allow to put child devices > > into the syscon device node. > > > > Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> regards Philipp > > --- > > Documentation/devicetree/bindings/mfd/syscon.txt | 11 +++++++++++ > > drivers/mfd/syscon.c | 2 ++ > > 2 files changed, 13 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt > > index fe8150b..a7e11d5 100644 > > --- a/Documentation/devicetree/bindings/mfd/syscon.txt > > +++ b/Documentation/devicetree/bindings/mfd/syscon.txt > > @@ -9,10 +9,21 @@ using a specific compatible value), interrogate the node (or associated > > OS driver) to determine the location of the registers, and access the > > registers directly. > > > > +Optionally, devices that are only controlled through single syscon > > +registers or bitfields can also be added as child nodes to the syscon > > +device node. These devices can implicitly assume their parent node > > +as syscon provider without referencing it explicitly via phandle. > > +In this case, the syscon node should have #address-cells = <1> and > > +#size-cells = <0> and no ranges property. > > + > > Required properties: > > - compatible: Should contain "syscon". > > - reg: the register region can be accessed from syscon > > > > +Optional properties: > > +- #address-cells: Should be 1. > > +- #size-cells: Should be 0. > > + > > Examples: > > gpr: iomuxc-gpr@020e0000 { > > compatible = "fsl,imx6q-iomuxc-gpr", "syscon"; > > diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c > > index dbea55d..1dde475 100644 > > --- a/drivers/mfd/syscon.c > > +++ b/drivers/mfd/syscon.c > > @@ -147,6 +147,8 @@ static int syscon_probe(struct platform_device *pdev) > > > > dev_dbg(dev, "regmap %pR registered\n", res); > > > > + of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev); > > + > > return 0; > > } > > > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
