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+Imagination Technologies Pistachio SoC pin controllers
+======================================================
+
+The pin controllers on Pistachio are a combined GPIO controller, (GPIO)
+interrupt controller, and pinmux + pinconf device. The system ("east") pin
+controller on Pistachio has 99 pins, 90 of which are MFIOs which can be
+configured as GPIOs. The 90 GPIOs are divided into 6 banks of up to 16 GPIOs
+each. The GPIO banks are represented as sub-nodes of the pad controller node.
+
+Please refer to pinctrl-bindings.txt, ../gpio/gpio.txt, and
+../interrupt-controller/interrupts.txt for generic information regarding
+pin controller, GPIO, and interrupt bindings.
+
+Required properties for pin controller node:
+--------------------------------------------
+ - compatible: "img,pistachio-system-pinctrl".
+ - reg: Address range of the pinctrl registers.
+
+Required properties for GPIO bank sub-nodes:
+--------------------------------------------
+ - interrupts: Interrupt line for the GPIO bank.
+ - gpio-controller: Indicates the device is a GPIO controller.
+ - #gpio-cells: Must be two. The first cell is the GPIO pin number and the
+ second cell indicates the polarity. See <dt-bindings/gpio/gpio.h> for
+ a list of possible values.
+ - interrupt-controller: Indicates the device is an interrupt controller.
+ - #interrupt-cells: Must be two. The first cell is the GPIO pin number and
+ the second cell encodes the interrupt flags. See
+ <dt-bindings/interrupt-controller/irq.h> for a list of valid flags.
+
+Note that the N GPIO bank sub-nodes *must* be named gpio0, gpio1, ... gpioN-1.
+
+Required properties for pin configuration sub-nodes:
+----------------------------------------------------
+ - pins: List of pins to which the configuration applies. See below for a
+ list of possible pins.
+
+Optional properties for pin configuration sub-nodes:
+----------------------------------------------------
+ - function: Mux function for the specified pins. This is not applicable for
+ non-MFIO pins. See below for a list of valid functions for each pin.
+ - bias-high-impedance: Enable high-impedance mode.
+ - bias-pull-up: Enable weak pull-up.
+ - bias-pull-down: Enable weak pull-down.
+ - bias-bus-hold: Enable bus-keeper mode.
+ - drive-strength: Drive strength in mA. Supported values: 2, 4, 8, 12.
+ - input-schmitt-enable: Enable Schmitt trigger.
+ - input-schmitt-disable: Disable Schmitt trigger.
+ - slew-rate: Slew rate control. 0 for slow, 1 for fast.
+
+Pin Functions
+--- ---------
+mfio0 spim1
+mfio1 spim1, spim0, uart1
+mfio2 spim1, spim0, uart1
+mfio3 spim1
+mfio4 spim1
+mfio5 spim1
+mfio6 spim1
+mfio7 spim1
+mfio8 spim0
+mfio9 spim0
+mfio10 spim0
+mfio11 spis
+mfio12 spis
+mfio13 spis
+mfio14 spis
+mfio15 sdhost, mips_trace_clk, mips_trace_data
+mfio16 sdhost, mips_trace_dint, mips_trace_data
+mfio17 sdhost, mips_trace_trigout, mips_trace_data
+mfio18 sdhost, mips_trace_trigin, mips_trace_data
+mfio19 sdhost, mips_trace_dm, mips_trace_data
+mfio20 sdhost, mips_trace_probe_n, mips_trace_data
+mfio21 sdhost, mips_trace_data
+mfio22 sdhost, mips_trace_data
+mfio23 sdhost
+mfio24 sdhost
+mfio25 sdhost
+mfio26 sdhost
+mfio27 sdhost
+mfio28 i2c0, spim0
+mfio29 i2c0, spim0
+mfio30 i2c1, spim0
+mfio31 i2c1, spim1
+mfio32 i2c2
+mfio33 i2c2
+mfio34 i2c3
+mfio35 i2c3
+mfio36 i2s_out, audio_clk_in
+mfio37 i2s_out, debug_raw_cca_ind
+mfio38 i2s_out, debug_ed_sec20_cca_ind
+mfio39 i2s_out, debug_ed_sec40_cca_ind
+mfio40 i2s_out, debug_agc_done_0
+mfio41 i2s_out, debug_agc_done_1
+mfio42 i2s_out, debug_ed_cca_ind
+mfio43 i2s_out, debug_s2l_done
+mfio44 i2s_out
+mfio45 i2s_dac_clk, audio_sync
+mfio46 audio_trigger
+mfio47 i2s_in
+mfio48 i2s_in
+mfio49 i2s_in
+mfio50 i2s_in
+mfio51 i2s_in
+mfio52 i2s_in
+mfio53 i2s_in
+mfio54 i2s_in, spdif_in
+mfio55 uart0, spim0, spim1
+mfio56 uart0, spim0, spim1
+mfio57 uart0, spim0, spim1
+mfio58 uart0, spim1
+mfio59 uart1
+mfio60 uart1
+mfio61 spdif_out
+mfio62 spdif_in
+mfio63 eth, mips_trace_clk, mips_trace_data
+mfio64 eth, mips_trace_dint, mips_trace_data
+mfio65 eth, mips_trace_trigout, mips_trace_data
+mfio66 eth, mips_trace_trigin, mips_trace_data
+mfio67 eth, mips_trace_dm, mips_trace_data
+mfio68 eth, mips_trace_probe_n, mips_trace_data
+mfio69 eth, mips_trace_data
+mfio70 eth, mips_trace_data
+mfio71 eth
+mfio72 ir
+mfio73 pwmpdm, mips_trace_clk, sram_debug
+mfio74 pwmpdm, mips_trace_dint, sram_debug
+mfio75 pwmpdm, mips_trace_trigout, rom_debug
+mfio76 pwmpdm, mips_trace_trigin, rom_debug
+mfio77 mdc_debug, mips_trace_dm, rpu_debug
+mfio78 mdc_debug, mips_trace_probe_n, rpu_debug
+mfio79 ddr_debug, mips_trace_data, mips_debug
+mfio80 ddr_debug, mips_trace_data, mips_debug
+mfio81 dreq0, mips_trace_data, eth_debug
+mfio82 dreq1, mips_trace_data, eth_debug
+mfio83 mips_pll_lock, mips_trace_data, usb_debug
+mfio84 sys_pll_lock, mips_trace_data, usb_debug
+mfio85 wifi_pll_lock, mips_trace_data, sdhost_debug
+mfio86 bt_pll_lock, mips_trace_data, sdhost_debug
+mfio87 rpu_v_pll_lock, dreq2, socif_debug
+mfio88 rpu_l_pll_lock, dreq3, socif_debug
+mfio89 audio_pll_lock, dreq4, dreq5
+tck
+trstn
+tdi
+tms
+tdo
+jtag_comply
+safe_mode
+por_disable
+resetn
+
+Example:
+--------
+pinctrl@18101C00 {
+ compatible = "img,pistachio-system-pinctrl";
+ reg = <0x18101C00 0x400>;
+
+ gpio0: gpio0 {
+ interrupts = <GIC_SHARED 71 IRQ_TYPE_LEVEL_HIGH>;
+
+ gpio-controller;
+ #gpio-cells = <2>;
+
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ };
+
+ ...
+
+ gpio5: gpio5 {
+ interrupts = <GIC_SHARED 76 IRQ_TYPE_LEVEL_HIGH>;
+
+ gpio-controller;
+ #gpio-cells = <2>;
+
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ };
+
+ ...
+
+ uart0_xfer: uart0-xfer {
+ uart0-rxd {
+ pins = "mfio55";
+ function = "uart0";
+ };
+ uart0-txd {
+ pins = "mfio56";
+ function = "uart0";
+ };
+ };
+
+ uart0_rts_cts: uart0-rts-cts {
+ uart0-rts {
+ pins = "mfio57";
+ function = "uart0";
+ };
+ uart0-cts {
+ pins = "mfio58";
+ function = "uart0";
+ };
+ };
+};
+
+uart@... {
+ ...
+ pinctrl-names = "default";
+ pinctrl-0 = <&uart0_xfer>, <&uart0_rts_cts>;
+ ...
+};
+
+usb_vbus: fixed-regulator {
+ ...
+ gpio = <&gpio5 6 GPIO_ACTIVE_HIGH>;
+ ...
+};