mfd: cpcap: Add minimal support

Many Motorola phones like droid 4 are using a custom PMIC called CPCAP
or 6556002. We can support it's core features quite easily with regmap_spi
and regmap_irq.

The children of cpcap, such as regulators, ADC and USB, can be just regular
device drivers and defined in the dts file. They get probed as we call
of_platform_populate() at the end of our probe, and then the children
can just call dev_get_regmap(dev.parent, NULL) to get the regmap.

Cc: devicetree@vger.kernel.org
Cc: Marcel Partap <mpartap@gmx.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Scott <michael.scott@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 31 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/mfd/motorola-cpcap.txt b/Documentation/devicetree/bindings/mfd/motorola-cpcap.txt
new file mode 100644
index 000000000000..15bc885f9df4
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/motorola-cpcap.txt
@@ -0,0 +1,31 @@
+Motorola CPCAP PMIC device tree binding
+
+Required properties:
+- compatible		: One or both of "motorola,cpcap" or "ste,6556002"
+- reg			: SPI chip select
+- interrupt-parent	: The parent interrupt controller
+- interrupts		: The interrupt line the device is connected to
+- interrupt-controller	: Marks the device node as an interrupt controller
+- #interrupt-cells	: The number of cells to describe an IRQ, should be 2
+- #address-cells	: Child device offset number of cells, should be 1
+- #size-cells		: Child device size number of cells, should be 0
+- spi-max-frequency	: Typically set to 3000000
+- spi-cs-high		: SPI chip select direction
+
+Example:
+
+&mcspi1 {
+	cpcap: pmic@0 {
+		compatible = "motorola,cpcap", "ste,6556002";
+		reg = <0>;	/* cs0 */
+		interrupt-parent = <&gpio1>;
+		interrupts = <7 IRQ_TYPE_EDGE_RISING>;
+		interrupt-controller;
+		#interrupt-cells = <2>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		spi-max-frequency = <3000000>;
+		spi-cs-high;
+	};
+};
+