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Diffstat (limited to 'Documentation/devicetree/bindings/pinctrl/nvidia,tegra20-pinmux.txt')
-rw-r--r-- | Documentation/devicetree/bindings/pinctrl/nvidia,tegra20-pinmux.txt | 131 |
1 files changed, 129 insertions, 2 deletions
diff --git a/Documentation/devicetree/bindings/pinctrl/nvidia,tegra20-pinmux.txt b/Documentation/devicetree/bindings/pinctrl/nvidia,tegra20-pinmux.txt index 36f82dbdd14..c8e578263ce 100644 --- a/Documentation/devicetree/bindings/pinctrl/nvidia,tegra20-pinmux.txt +++ b/Documentation/devicetree/bindings/pinctrl/nvidia,tegra20-pinmux.txt @@ -1,5 +1,132 @@ -NVIDIA Tegra 2 pinmux controller +NVIDIA Tegra20 pinmux controller Required properties: -- compatible : "nvidia,tegra20-pinmux" +- compatible: "nvidia,tegra20-pinmux" +- reg: Should contain the register physical address and length for each of + the tri-state, mux, pull-up/down, and pad control register sets. +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". + +Tegra's pin configuration nodes act as a container for an abitrary number of +subnodes. Each of these subnodes represents some desired configuration for a +pin, a group, or a list of pins or groups. This configuration can include the +mux function to select on those pin(s)/group(s), and various pin configuration +parameters, such as pull-up, tristate, drive strength, etc. + +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 or tristate parameter. For this +reason, even seemingly boolean values are actually tristates in this binding: +unspecified, off, or on. Unspecified is represented as an absent property, +and off/on are represented as integer values 0 and 1. + +Required subnode-properties: +- nvidia,pins : An array of strings. Each string contains the name of a pin or + group. Valid values for these names are listed below. + +Optional subnode-properties: +- nvidia,function: A string containing the name of the function to mux to the + pin or group. Valid values for function names are listed below. See the Tegra + TRM to determine which are valid for each pin or group. +- nvidia,pull: Integer, representing the pull-down/up to apply to the pin. + 0: none, 1: down, 2: up. +- nvidia,tristate: Integer. + 0: drive, 1: tristate. +- nvidia,high-speed-mode: Integer. Enable high speed mode the pins. + 0: no, 1: yes. +- nvidia,schmitt: Integer. Enables Schmitt Trigger on the input. + 0: no, 1: yes. +- nvidia,low-power-mode: Integer. Valid values 0-3. 0 is least power, 3 is + most power. Controls the drive power or current. See "Low Power Mode" + or "LPMD1" and "LPMD0" in the Tegra TRM. +- nvidia,pull-down-strength: Integer. Controls drive strength. 0 is weakest. + The range of valid values depends on the pingroup. See "CAL_DRVDN" in the + Tegra TRM. +- nvidia,pull-up-strength: Integer. Controls drive strength. 0 is weakest. + The range of valid values depends on the pingroup. See "CAL_DRVUP" in the + Tegra TRM. +- nvidia,slew-rate-rising: Integer. Controls rising signal slew rate. 0 is + fastest. The range of valid values depends on the pingroup. See + "DRVDN_SLWR" in the Tegra TRM. +- nvidia,slew-rate-falling: Integer. Controls falling signal slew rate. 0 is + fastest. The range of valid values depends on the pingroup. See + "DRVUP_SLWF" in the Tegra TRM. + +Note that many of these properties are only valid for certain specific pins +or groups. See the Tegra TRM and various pinmux spreadsheets for complete +details regarding which groups support which functionality. The Linux pinctrl +driver may also be a useful reference, since it consolidates, disambiguates, +and corrects data from all those sources. + +Valid values for pin and group names are: + + mux groups: + + These all support nvidia,function, nvidia,tristate, and many support + nvidia,pull. + + ata, atb, atc, atd, ate, cdev1, cdev2, crtp, csus, dap1, dap2, dap3, dap4, + ddc, dta, dtb, dtc, dtd, dte, dtf, gma, gmb, gmc, gmd, gme, gpu, gpu7, + gpv, hdint, i2cp, irrx, irtx, kbca, kbcb, kbcc, kbcd, kbce, kbcf, lcsn, + ld0, ld1, ld2, ld3, ld4, ld5, ld6, ld7, ld8, ld9, ld10, ld11, ld12, ld13, + ld14, ld15, ld16, ld17, ldc, ldi, lhp0, lhp1, lhp2, lhs, lm0, lm1, lpp, + lpw0, lpw1, lpw2, lsc0, lsc1, lsck, lsda, lsdi, lspi, lvp0, lvp1, lvs, + owc, pmc, pta, rm, sdb, sdc, sdd, sdio1, slxa, slxc, slxd, slxk, spdi, + spdo, spia, spib, spic, spid, spie, spif, spig, spih, uaa, uab, uac, uad, + uca, ucb, uda. + + tristate groups: + + These only support nvidia,pull. + + ck32, ddrc, pmca, pmcb, pmcc, pmcd, pmce, xm2c, xm2d, ls, lc, ld17_0, + ld19_18, ld21_20, ld23_22. + + drive groups: + + With some exceptions, these support nvidia,high-speed-mode, + nvidia,schmitt, nvidia,low-power-mode, nvidia,pull-down-strength, + nvidia,pull-up-strength, nvidia,slew_rate-rising, nvidia,slew_rate-falling. + + drive_ao1, drive_ao2, drive_at1, drive_at2, drive_cdev1, drive_cdev2, + drive_csus, drive_dap1, drive_dap2, drive_dap3, drive_dap4, drive_dbg, + drive_lcd1, drive_lcd2, drive_sdmmc2, drive_sdmmc3, drive_spi, drive_uaa, + drive_uab, drive_uart2, drive_uart3, drive_vi1, drive_vi2, drive_xm2a, + drive_xm2c, drive_xm2d, drive_xm2clk, drive_sdio1, drive_crt, drive_ddc, + drive_gma, drive_gmb, drive_gmc, drive_gmd, drive_gme, drive_owr, + drive_uda. + +Example: + + pinctrl@70000000 { + compatible = "nvidia,tegra20-pinmux"; + reg = < 0x70000014 0x10 /* Tri-state registers */ + 0x70000080 0x20 /* Mux registers */ + 0x700000a0 0x14 /* Pull-up/down registers */ + 0x70000868 0xa8 >; /* Pad control registers */ + }; + +Example board file extract: + + pinctrl@70000000 { + sdio4_default: sdio4_default { + atb { + nvidia,pins = "atb", "gma", "gme"; + nvidia,function = "sdio4"; + nvidia,pull = <0>; + nvidia,tristate = <0>; + }; + }; + }; + + sdhci@c8000600 { + pinctrl-names = "default"; + pinctrl-0 = <&sdio4_default>; + }; |