Initial import

diff --git a/Makefile b/Makefile
new file mode 100644 (file)
index 0000000..c5d4c93
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,20 @@
+PART_NUMBER = bbb-eqep2b-ao2
+VERSION = 00A0
+
+# To get the include files, clone the repository from
+# https://github.com/beagleboard/bb.org-overlays.git
+# parallel to this directory.
+
+INCLUDE_PATH = ../bb.org-overlays/include
+
+compile: $(PART_NUMBER)-$(VERSION).dtbo
+
+install: compile
+       cp $(PART_NUMBER)-$(VERSION).dtbo /lib/firmware
+
+clean:
+       rm -f *.dtbo *.dts.tmp *~
+
+%.dtbo: %.dts
+       cpp -nostdinc -undef -D__DTS__ -I$(INCLUDE_PATH) -x assembler-with-cpp -o $<.tmp $<
+       dtc -Wno-unit_address_vs_reg -O dtb -o $@ -b 0 -@ $<.tmp

diff --git a/bbb-eqep2b-ao2-00A0.dts b/bbb-eqep2b-ao2-00A0.dts
new file mode 100644 (file)
index 0000000..0eaf9e3
--- /dev/null
+++ b/bbb-eqep2b-ao2-00A0.dts
@@ -0,0 +1,88 @@
+/*
+ * Set up eQEP in a way that does not conflict with HDMI.
+ *
+ * Copyright (C) 2013  Nathaniel R. Lewis - http://nathanielrlewis.com/
+ * Copyright (C) 2018  Antonio Ospite <ao2@ao2.it>
+ *
+ * This program is free softwarejc you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/board/am335x-bbw-bbb-base.h>
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/pinctrl/am33xx.h>
+
+/ {
+       compatible = "ti,beaglebone", "ti,beaglebone-black";
+
+       // Identification.
+       part-number = "bbb-eqep2b-ao2";
+       version     = "00A0";
+
+       // Resources this cape uses.
+       exclusive-use =
+               "P8.12",        // EQEP2A_in
+               "P8.11",        // EQEP2B_in
+               "P8.16",        // EQEP2_index
+               "P8.15",        // EQEP2_strobe
+
+               "eqep2";        // hardware ip used
+
+       fragment@0 {
+               target = <&am33xx_pinmux>;
+               __overlay__ {
+                       pinctrl_eqep2: pinctrl_eqep2_pins {
+                               pinctrl-single,pins = <
+                                       BONE_P8_12 (PIN_INPUT | MUX_MODE4)      // GPIO1_12 = EQEP2A_in
+                                       BONE_P8_11 (PIN_INPUT | MUX_MODE4)      // GPIO1_13 = EQEP2B_in
+                                       BONE_P8_16 (PIN_INPUT | MUX_MODE4)      // GPIO1_14 = EQEP2_index
+                                       BONE_P8_15 (PIN_INPUT | MUX_MODE4)      // GPIO1_15 = EQEP2_strobe
+                                       // From: https://groups.google.com/forum/#!searchin/beagleboard/eQep/beagleboard/Orp3tFcNgCc/mYacP_GkCQQJ
+                               >;
+                       };
+               };
+       };
+
+       fragment@1 {
+               target = <&epwmss2>;
+               __overlay__ {
+                       status = "okay";
+               };
+       };
+
+       fragment@2 {
+               target = <&eqep2>;
+               __overlay__ {
+                       pinctrl-names = "default";
+                       pinctrl-0 = <&pinctrl_eqep2>;
+
+                       count_mode = <0>;       // count_mode is not userspace op_mode
+                       // 0 -> Quadrature mode, normal 90 phase offset cha & chb.
+                       // 1 -> Direction mode.  cha input = clock, chb input = direction
+                       // 2 -> UP count mode for frequency measurement QDIR=1, ignore direction input
+                       // 3 -> DOWN count mode for frequency measurement QDIR=0, ignore direction input
+
+                       swap_inputs = <0>;      // swap channel A and B? (0 - no, 1 - yes)
+                       invert_qa = <1>;        // invert channel A input?
+                       invert_qb = <1>;        // invert channel B input?
+                       invert_qi = <0>;        // invert index input?
+                       invert_qs = <0>;        // invert strobe input?
+                       omit_interrupt = <0>;   // 1 -> do not install interrupt handler, 0 -> do install
+
+                       status = "okay";
+               };
+       };
+};

diff --git a/eQEP-test.sh b/eQEP-test.sh
new file mode 100755 (executable)
index 0000000..dd0e105
--- /dev/null
+++ b/eQEP-test.sh
@@ -0,0 +1,8 @@
+#!/bin/sh
+
+set -e
+
+while true;
+do
+  cat /sys/devices/platform/ocp/48304000.epwmss/48304180.eqep/position
+done