regulator: add pbias regulator support

pbias register controls internal power supply to sd card i/o pads
in most OMAPs (OMAP2-5, DRA7).
Control bits for selecting voltage level and
enabling/disabling are in the same PBIAS register.

Signed-off-by: Balaji T K <balajitk@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Mark Brown <broonie@linaro.org>
Tested-by: Florian Vaussard <florian.vaussard@epfl.ch>
Tested-by: Stefan Roese <sr@denx.de>
Signed-off-by: Chris Ball <chris@printf.net>

1 files changed, 27 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/regulator/pbias-regulator.txt b/Documentation/devicetree/bindings/regulator/pbias-regulator.txt
new file mode 100644
index 000000000000..32aa26f1e434
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/pbias-regulator.txt
@@ -0,0 +1,27 @@
+PBIAS internal regulator for SD card dual voltage i/o pads on OMAP SoCs.
+
+Required properties:
+- compatible:
+  - "ti,pbias-omap" for OMAP2, OMAP3, OMAP4, OMAP5, DRA7.
+- reg: pbias register offset from syscon base and size of pbias register.
+- syscon : phandle of the system control module
+- regulator-name : should be
+                        pbias_mmc_omap2430 for OMAP2430, OMAP3 SoCs
+                        pbias_sim_omap3 for OMAP3 SoCs
+                        pbias_mmc_omap4 for OMAP4 SoCs
+                        pbias_mmc_omap5 for OMAP5 and DRA7 SoC
+
+Optional properties:
+- Any optional property defined in bindings/regulator/regulator.txt
+
+Example:
+
+                pbias_regulator: pbias_regulator {
+                        compatible = "ti,pbias-omap";
+                        reg = <0 0x4>;
+                        syscon = <&omap5_padconf_global>;
+                        pbias_mmc_reg: pbias_mmc_omap5 {
+                                regulator-name = "pbias_mmc_omap5";
+                                regulator-min-microvolt = <1800000>;
+                                regulator-max-microvolt = <3000000>;
+                        };