bbb-eqep2b-ao2-00A0.dts

   1 /*
   2  * Set up eQEP in a way that does not conflict with HDMI.
   3  *
   4  * Copyright (C) 2013  Nathaniel R. Lewis - http://nathanielrlewis.com/
   5  * Copyright (C) 2018  Antonio Ospite <ao2@ao2.it>
   6  *
   7  * This program is free softwarejc you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 /dts-v1/;
  22 /plugin/;
  23
  24 #include <dt-bindings/board/am335x-bbw-bbb-base.h>
  25 #include <dt-bindings/gpio/gpio.h>
  26 #include <dt-bindings/pinctrl/am33xx.h>
  27
  28 / {
  29         compatible = "ti,beaglebone", "ti,beaglebone-black";
  30
  31         // Identification.
  32         part-number = "bbb-eqep2b-ao2";
  33         version     = "00A0";
  34
  35         // Resources this cape uses.
  36         exclusive-use =
  37                 "P8.12",        // EQEP2A_in
  38                 "P8.11",        // EQEP2B_in
  39                 "P8.16",        // EQEP2_index
  40                 "P8.15",        // EQEP2_strobe
  41
  42                 "eqep2";        // hardware ip used
  43
  44         fragment@0 {
  45                 target = <&am33xx_pinmux>;
  46                 __overlay__ {
  47                         pinctrl_eqep2: pinctrl_eqep2_pins {
  48                                 pinctrl-single,pins = <
  49                                         BONE_P8_12 (PIN_INPUT | MUX_MODE4)      // GPIO1_12 = EQEP2A_in
  50                                         BONE_P8_11 (PIN_INPUT | MUX_MODE4)      // GPIO1_13 = EQEP2B_in
  51                                         BONE_P8_16 (PIN_INPUT | MUX_MODE4)      // GPIO1_14 = EQEP2_index
  52                                         BONE_P8_15 (PIN_INPUT | MUX_MODE4)      // GPIO1_15 = EQEP2_strobe
  53                                         // From: https://groups.google.com/forum/#!searchin/beagleboard/eQep/beagleboard/Orp3tFcNgCc/mYacP_GkCQQJ
  54                                 >;
  55                         };
  56                 };
  57         };
  58
  59         fragment@1 {
  60                 target = <&epwmss2>;
  61                 __overlay__ {
  62                         status = "okay";
  63                 };
  64         };
  65
  66         fragment@2 {
  67                 target = <&eqep2>;
  68                 __overlay__ {
  69                         pinctrl-names = "default";
  70                         pinctrl-0 = <&pinctrl_eqep2>;
  71
  72                         count_mode = <0>;       // count_mode is not userspace op_mode
  73                         // 0 -> Quadrature mode, normal 90 phase offset cha & chb.
  74                         // 1 -> Direction mode.  cha input = clock, chb input = direction
  75                         // 2 -> UP count mode for frequency measurement QDIR=1, ignore direction input
  76                         // 3 -> DOWN count mode for frequency measurement QDIR=0, ignore direction input
  77
  78                         swap_inputs = <0>;      // swap channel A and B? (0 - no, 1 - yes)
  79                         invert_qa = <1>;        // invert channel A input?
  80                         invert_qb = <1>;        // invert channel B input?
  81                         invert_qi = <0>;        // invert index input?
  82                         invert_qs = <0>;        // invert strobe input?
  83                         omit_interrupt = <0>;   // 1 -> do not install interrupt handler, 0 -> do install
  84
  85                         status = "okay";
  86                 };
  87         };
  88 };