1NVIDIA Tegra20 pinmux controller
   3Required properties:
   4- compatible: "nvidia,tegra20-pinmux"
   5- reg: Should contain the register physical address and length for each of
   6  the tri-state, mux, pull-up/down, and pad control register sets.
   8Please refer to pinctrl-bindings.txt in this directory for details of the
   9common pinctrl bindings used by client devices, including the meaning of the
  10phrase "pin configuration node".
  12Tegra's pin configuration nodes act as a container for an abitrary number of
  13subnodes. Each of these subnodes represents some desired configuration for a
  14pin, a group, or a list of pins or groups. This configuration can include the
  15mux function to select on those pin(s)/group(s), and various pin configuration
  16parameters, such as pull-up, tristate, drive strength, etc.
  18The name of each subnode is not important; all subnodes should be enumerated
  19and processed purely based on their content.
  21Each subnode only affects those parameters that are explicitly listed. In
  22other words, a subnode that lists a mux function but no pin configuration
  23parameters implies no information about any pin configuration parameters.
  24Similarly, a pin subnode that describes a pullup parameter implies no
  25information about e.g. the mux function or tristate parameter. For this
  26reason, even seemingly boolean values are actually tristates in this binding:
  27unspecified, off, or on. Unspecified is represented as an absent property,
  28and off/on are represented as integer values 0 and 1.
  30Required subnode-properties:
  31- nvidia,pins : An array of strings. Each string contains the name of a pin or
  32    group. Valid values for these names are listed below.
  34Optional subnode-properties:
  35- nvidia,function: A string containing the name of the function to mux to the
  36  pin or group. Valid values for function names are listed below. See the Tegra
  37  TRM to determine which are valid for each pin or group.
  38- nvidia,pull: Integer, representing the pull-down/up to apply to the pin.
  39    0: none, 1: down, 2: up.
  40- nvidia,tristate: Integer.
  41    0: drive, 1: tristate.
  42- nvidia,high-speed-mode: Integer. Enable high speed mode the pins.
  43    0: no, 1: yes.
  44- nvidia,schmitt: Integer. Enables Schmitt Trigger on the input.
  45    0: no, 1: yes.
  46- nvidia,low-power-mode: Integer. Valid values 0-3. 0 is least power, 3 is
  47    most power. Controls the drive power or current. See "Low Power Mode"
  48    or "LPMD1" and "LPMD0" in the Tegra TRM.
  49- nvidia,pull-down-strength: Integer. Controls drive strength. 0 is weakest.
  50    The range of valid values depends on the pingroup. See "CAL_DRVDN" in the
  51    Tegra TRM.
  52- nvidia,pull-up-strength: Integer. Controls drive strength. 0 is weakest.
  53    The range of valid values depends on the pingroup. See "CAL_DRVUP" in the
  54    Tegra TRM.
  55- nvidia,slew-rate-rising: Integer. Controls rising signal slew rate. 0 is
  56    fastest. The range of valid values depends on the pingroup. See
  57    "DRVDN_SLWR" in the Tegra TRM.
  58- nvidia,slew-rate-falling: Integer. Controls falling signal slew rate. 0 is
  59    fastest. The range of valid values depends on the pingroup. See
  60    "DRVUP_SLWF" in the Tegra TRM.
  62Note that many of these properties are only valid for certain specific pins
  63or groups. See the Tegra TRM and various pinmux spreadsheets for complete
  64details regarding which groups support which functionality. The Linux pinctrl
  65driver may also be a useful reference, since it consolidates, disambiguates,
  66and corrects data from all those sources.
  68Valid values for pin and group names are:
  70  mux groups:
  72    These all support nvidia,function, nvidia,tristate, and many support
  73    nvidia,pull.
  75    ata, atb, atc, atd, ate, cdev1, cdev2, crtp, csus, dap1, dap2, dap3, dap4,
  76    ddc, dta, dtb, dtc, dtd, dte, dtf, gma, gmb, gmc, gmd, gme, gpu, gpu7,
  77    gpv, hdint, i2cp, irrx, irtx, kbca, kbcb, kbcc, kbcd, kbce, kbcf, lcsn,
  78    ld0, ld1, ld2, ld3, ld4, ld5, ld6, ld7, ld8, ld9, ld10, ld11, ld12, ld13,
  79    ld14, ld15, ld16, ld17, ldc, ldi, lhp0, lhp1, lhp2, lhs, lm0, lm1, lpp,
  80    lpw0, lpw1, lpw2, lsc0, lsc1, lsck, lsda, lsdi, lspi, lvp0, lvp1, lvs,
  81    owc, pmc, pta, rm, sdb, sdc, sdd, sdio1, slxa, slxc, slxd, slxk, spdi,
  82    spdo, spia, spib, spic, spid, spie, spif, spig, spih, uaa, uab, uac, uad,
  83    uca, ucb, uda.
  85  tristate groups:
  87    These only support nvidia,pull.
  89    ck32, ddrc, pmca, pmcb, pmcc, pmcd, pmce, xm2c, xm2d, ls, lc, ld17_0,
  90    ld19_18, ld21_20, ld23_22.
  92  drive groups:
  94    With some exceptions, these support nvidia,high-speed-mode,
  95    nvidia,schmitt, nvidia,low-power-mode, nvidia,pull-down-strength,
  96    nvidia,pull-up-strength, nvidia,slew-rate-rising, nvidia,slew-rate-falling.
  98    drive_ao1, drive_ao2, drive_at1, drive_at2, drive_cdev1, drive_cdev2,
  99    drive_csus, drive_dap1, drive_dap2, drive_dap3, drive_dap4, drive_dbg,
 100    drive_lcd1, drive_lcd2, drive_sdmmc2, drive_sdmmc3, drive_spi, drive_uaa,
 101    drive_uab, drive_uart2, drive_uart3, drive_vi1, drive_vi2, drive_xm2a,
 102    drive_xm2c, drive_xm2d, drive_xm2clk, drive_sdio1, drive_crt, drive_ddc,
 103    drive_gma, drive_gmb, drive_gmc, drive_gmd, drive_gme, drive_owr,
 104    drive_uda.
 108        pinctrl@70000000 {
 109                compatible = "nvidia,tegra20-pinmux";
 110                reg = < 0x70000014 0x10    /* Tri-state registers */
 111                        0x70000080 0x20    /* Mux registers */
 112                        0x700000a0 0x14    /* Pull-up/down registers */
 113                        0x70000868 0xa8 >; /* Pad control registers */
 114        };
 116Example board file extract:
 118        pinctrl@70000000 {
 119                sdio4_default: sdio4_default {
 120                        atb {
 121                                nvidia,pins = "atb", "gma", "gme";
 122                                nvidia,function = "sdio4";
 123                                nvidia,pull = <0>;
 124                                nvidia,tristate = <0>;
 125                        };
 126                };
 127        };
 129        sdhci@c8000600 {
 130                pinctrl-names = "default";
 131                pinctrl-0 = <&sdio4_default>;
 132        };