1 Microsemi Corporation (MSCC) Serial GPIO driver
3 The MSCC serial GPIO extends the number or GPIO's on the system by
4 means of 4 dedicated pins: one input, one output, one clock and one
5 strobe pin. By attaching a number of (external) shift registers, the
6 effective GPIO count can be extended by up to 128 GPIO's per
10 - compatible : "mscc,luton-sgpio" or "mscc,ocelot-sgpio"
11 - clock: Reference clock used to generate clock divider setting. See
12 mscc,sgpio-frequency property.
13 - reg : Physical base address and length of the controller's registers.
14 - #gpio-cells : Should be two. The first cell is the pin number and the
15 second cell is used to specify optional parameters:
16 - bit 0 specifies polarity (0 for normal, 1 for inverted)
17 - gpio-controller : Marks the device node as a GPIO controller.
18 - gpio-ranges: Standard gpio range(s): phandle, gpio base, pinctrl base
22 - ngpios: See gpio.txt
23 - mscc,sgpio-frequency: The frequency at which the serial bitstream is
24 generated and sampled. Default: 12500000 (Hz).
25 - mscc,sgpio-ports: A bitmask (32 bits) of which ports are enabled in
26 the serialized gpio stream. One 'port' will transport from 1 to 4
27 gpio bits. Default: 0xFFFFFFFF.
29 Typically the pinctrl-0 and pinctrl-names properties will also be
30 present to enable the use of the SIO CLK, LD, DI and DO for some
36 compatible = "mscc,ocelot-sgpio";
37 pinctrl-0 = <&sgpio_pins>;
38 pinctrl-names = "default";
39 reg = <0x10700f8 0x100>;
42 gpio-ranges = <&sgpio 0 0 64>;
43 mscc,sgpio-frequency = <12500>;
44 mscc,sgpio-ports = <0x000FFFFF>;