pinctrl: palmas: add pincontrol driver

TI Palmas series Power Management IC have multiple pins which can be
configured for different functionality. This pins can be configured
for different function. Also their properties like pull up/down,
open drain enable/disable are configurable.

Add support for pincontrol driver Palmas series device like TPS65913,
TPS80036. The driver supports to be register from DT only.

Changes from V1:
- Add generic property for pins and functions in pinconf-generic.
- Add APIs to map the DT and subnode.
- Move common utils APIs to the pinctrl-utils from this file.
- Update the binding document accordingly.
Changes from V2:
- Add ack by Lee.
- Correct the binding docs.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 96 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-palmas.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-palmas.txt
new file mode 100644
index 000000000000..734d9b04d533
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-palmas.txt
@@ -0,0 +1,96 @@
+Palmas Pincontrol bindings
+
+The pins of Palmas device can be set on different option and provides
+the configuration for Pull UP/DOWN, open drain etc.
+
+Required properties:
+- compatible: It must be one of following:
+  - "ti,palmas-pinctrl" for Palma series of the pincontrol.
+  - "ti,tps65913-pinctrl" for Palma series device TPS65913.
+  - "ti,tps80036-pinctrl" for Palma series device TPS80036.
+
+Please refer to pinctrl-bindings.txt in this directory for details of the
+common pinctrl bindings used by client devices, including the meaning of the
+phrase "pin configuration node".
+
+Palmas's pin configuration nodes act as a container for an arbitrary number of
+subnodes. Each of these subnodes represents some desired configuration for a
+list of pins. This configuration can include the mux function to select on
+those pin(s), and various pin configuration parameters, such as pull-up,
+open drain.
+
+The name of each subnode is not important; all subnodes should be enumerated
+and processed purely based on their content.
+
+Each subnode only affects those parameters that are explicitly listed. In
+other words, a subnode that lists a mux function but no pin configuration
+parameters implies no information about any pin configuration parameters.
+Similarly, a pin subnode that describes a pullup parameter implies no
+information about e.g. the mux function.
+
+Optional properties:
+- ti,palmas-enable-dvfs1: Enable DVFS1. Configure pins for DVFS1 mode.
+	Selection primary or secondary function associated to I2C2_SCL_SCE,
+	I2C2_SDA_SDO pin/pad for DVFS1 interface
+- ti,palmas-enable-dvfs2: Enable DVFS2. Configure pins for DVFS2 mode.
+	Selection primary or secondary function associated to GPADC_START
+	and SYSEN2 pin/pad for DVFS2 interface
+
+This binding uses the following generic properties as defined in
+pinctrl-bindings.txt:
+
+Required: pins
+Options: function, bias-disable, bias-pull-up, bias-pull-down,
+	 bias-pin-default, drive-open-drain.
+
+Note that many of these properties are only valid for certain specific pins.
+See the Palmas device datasheet for complete details regarding which pins
+support which functionality.
+
+Valid values for pin names are:
+	gpio0, gpio1, gpio2, gpio3, gpio4, gpio5, gpio6, gpio7, gpio8, gpio9,
+	gpio10, gpio11, gpio12, gpio13, gpio14, gpio15, vac, powergood,
+	nreswarm, pwrdown, gpadc_start, reset_in, nsleep, enable1, enable2,
+	int.
+
+Valid value of function names are:
+	gpio, led, pwm, regen, sysen, clk32kgaudio, id, vbus_det, chrg_det,
+	vac, vacok, powergood, usb_psel, msecure, pwrhold, int, nreswarm,
+	simrsto, simrsti, low_vbat, wireless_chrg1, rcm, pwrdown, gpadc_start,
+	reset_in, nsleep, enable.
+
+There are 4 special functions: opt0, opt1, opt2 and opt3. If any of these
+functions is selected then directly pins register will be written with 0, 1, 2
+or 3 respectively if it is valid for that pins or list of pins.
+
+Example:
+	palmas: tps65913 {
+		....
+		pinctrl {
+			compatible = "ti,tps65913-pinctrl";
+			ti,palmas-enable-dvfs1;
+			pinctrl-names = "default";
+			pinctrl-0 = <&palmas_pins_state>;
+
+			palmas_pins_state: pinmux {
+				gpio0 {
+					pins = "gpio0";
+					function = "id";
+					bias-pull-up;
+				};
+
+				vac {
+					pins = "vac";
+					function = "vacok";
+					bias-pull-down;
+				};
+
+				gpio5 {
+					pins = "gpio5";
+					function = "opt0";
+					drive-open-drain = <1>;
+				};
+			};
+		};
+		....
+	};