From 7cfb4fac2893457d9f4656bffbb9743c815a098f Mon Sep 17 00:00:00 2001
From: Barry Carter <barry.carter@openservo.org>
Date: Tue, 21 Jul 2015 20:10:49 +0100
Subject: [PATCH] Add Teensy LC support. Note: disables spi4teensy lib. (Barry
 Carter)

---
 avrpins.h  | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 settings.h |  8 ++++++-
 usbhost.h  |  4 +++-
 3 files changed, 74 insertions(+), 2 deletions(-)

diff --git a/avrpins.h b/avrpins.h
index 4e60e3a2..05c9ab79 100644
--- a/avrpins.h
+++ b/avrpins.h
@@ -835,6 +835,70 @@ MAKE_PIN(P33, CORE_PIN33_PORTREG, CORE_PIN33_BIT, CORE_PIN33_CONFIG);
 
 #undef MAKE_PIN
 
+#elif defined(CORE_TEENSY) && (defined(__MKL26Z64__))
+
+// we could get lower level by making these macros work properly.
+// for now just use the semi optimised version, it costs a lookup in the pin pgm table per op
+// but for now it will do.
+//#define GPIO_BITBAND_ADDR(reg, bit) (((volatile uint8_t *)&(reg) + ((bit) >> 3)))
+//#define GPIO_BITBAND_MASK(reg, bit) (1<<((bit) & 7))
+//#define GPIO_BITBAND_PTR(reg, bit) ((volatile uint8_t *)GPIO_BITBAND_ADDR((reg), (bit)))
+
+#include "core_pins.h"
+#include "avr_emulation.h"
+
+#define MAKE_PIN(className, baseReg, pinNum, configReg) \
+class className { \
+public: \
+  static void Set() { \
+    *portSetRegister(pinNum) = digitalPinToBitMask(pinNum); \
+  } \
+  static void Clear() { \
+    *portClearRegister(pinNum) = digitalPinToBitMask(pinNum); \
+  } \
+  static void SetDirRead() { \
+    configReg = PORT_PCR_SRE | PORT_PCR_DSE | PORT_PCR_MUX(1); \
+    *portModeRegister(pinNum) &= ~digitalPinToBitMask(pinNum); \
+  } \
+  static void SetDirWrite() { \
+    configReg = PORT_PCR_SRE | PORT_PCR_DSE | PORT_PCR_MUX(1); \
+    *portModeRegister(pinNum) |= digitalPinToBitMask(pinNum); \
+  } \
+  static uint8_t IsSet() { \
+    return (*portInputRegister(pinNum) & digitalPinToBitMask(pinNum)) ? 1 : 0; \
+  } \
+};
+
+MAKE_PIN(P0, CORE_PIN0_PORTREG, 0, CORE_PIN0_CONFIG);
+MAKE_PIN(P1, CORE_PIN1_PORTREG, 1, CORE_PIN1_CONFIG);
+MAKE_PIN(P2, CORE_PIN2_PORTREG, 2, CORE_PIN2_CONFIG);
+MAKE_PIN(P3, CORE_PIN3_PORTREG, 3, CORE_PIN3_CONFIG);
+MAKE_PIN(P4, CORE_PIN4_PORTREG, 4, CORE_PIN4_CONFIG);
+MAKE_PIN(P5, CORE_PIN5_PORTREG, 5, CORE_PIN5_CONFIG);
+MAKE_PIN(P6, CORE_PIN6_PORTREG, 6, CORE_PIN6_CONFIG);
+MAKE_PIN(P7, CORE_PIN7_PORTREG, 7, CORE_PIN7_CONFIG);
+MAKE_PIN(P8, CORE_PIN8_PORTREG, 8, CORE_PIN8_CONFIG);
+MAKE_PIN(P9, CORE_PIN9_PORTREG, 9, CORE_PIN9_CONFIG);
+MAKE_PIN(P10, CORE_PIN10_PORTREG, 10, CORE_PIN10_CONFIG);
+MAKE_PIN(P11, CORE_PIN11_PORTREG, 11, CORE_PIN11_CONFIG);
+MAKE_PIN(P12, CORE_PIN12_PORTREG, 12, CORE_PIN12_CONFIG);
+MAKE_PIN(P13, CORE_PIN13_PORTREG, 13, CORE_PIN13_CONFIG);
+MAKE_PIN(P14, CORE_PIN14_PORTREG, 14, CORE_PIN14_CONFIG);
+MAKE_PIN(P15, CORE_PIN15_PORTREG, 15, CORE_PIN15_CONFIG);
+MAKE_PIN(P16, CORE_PIN16_PORTREG, 16, CORE_PIN16_CONFIG);
+MAKE_PIN(P17, CORE_PIN17_PORTREG, 17, CORE_PIN17_CONFIG);
+MAKE_PIN(P18, CORE_PIN18_PORTREG, 18, CORE_PIN18_CONFIG);
+MAKE_PIN(P19, CORE_PIN19_PORTREG, 19, CORE_PIN19_CONFIG);
+MAKE_PIN(P20, CORE_PIN20_PORTREG, 20, CORE_PIN20_CONFIG);
+MAKE_PIN(P21, CORE_PIN21_PORTREG, 21, CORE_PIN21_CONFIG);
+MAKE_PIN(P22, CORE_PIN22_PORTREG, 22, CORE_PIN22_CONFIG);
+MAKE_PIN(P23, CORE_PIN23_PORTREG, 23, CORE_PIN23_CONFIG);
+MAKE_PIN(P24, CORE_PIN24_PORTREG, 24, CORE_PIN24_CONFIG);
+MAKE_PIN(P25, CORE_PIN25_PORTREG, 25, CORE_PIN25_CONFIG);
+MAKE_PIN(P26, CORE_PIN26_PORTREG, 26, CORE_PIN26_CONFIG);
+
+#undef MAKE_PIN
+
 #elif defined(ARDUINO_SAM_DUE) && defined(__SAM3X8E__)
 
 // SetDirRead:
diff --git a/settings.h b/settings.h
index 5c060354..9d3a69cd 100644
--- a/settings.h
+++ b/settings.h
@@ -71,6 +71,12 @@ e-mail   :  support@circuitsathome.com
 #define USE_SPI4TEENSY3 1
 #endif
 
+// disabled on the Teensy LC as it is incompatible for now
+#if defined(__MKL26Z64__)
+#undef USE_SPI4TEENSY3
+#define USE_SPI4TEENSY3 0
+#endif
+
 ////////////////////////////////////////////////////////////////////////////////
 // AUTOMATIC Settings
 ////////////////////////////////////////////////////////////////////////////////
@@ -123,7 +129,7 @@ e-mail   :  support@circuitsathome.com
 #define EXT_RAM 0
 #endif
 
-#if defined(CORE_TEENSY) && (defined(__MK20DX128__) || defined(__MK20DX256__))
+#if defined(CORE_TEENSY) && (defined(__MK20DX128__) || defined(__MK20DX256__) || defined(__MKL26Z64__))
 #define USING_SPI4TEENSY3 USE_SPI4TEENSY3
 #else
 #define USING_SPI4TEENSY3 0
diff --git a/usbhost.h b/usbhost.h
index e610d938..383ce7e8 100644
--- a/usbhost.h
+++ b/usbhost.h
@@ -42,6 +42,8 @@ public:
 #elif SPI_HAS_TRANSACTION
         static void init() {
                 SPI.begin(); // The SPI library with transaction will take care of setting up the pins - settings is set in beginTransaction()
+                SPI_SS::SetDirWrite();
+                SPI_SS::Set();
         }
 #elif !defined(SPDR)
         static void init() {
@@ -84,7 +86,7 @@ typedef SPi< Pb1, Pb2, Pb3, Pb0 > spi;
 typedef SPi< Pb5, Pb3, Pb4, Pb2 > spi;
 #elif defined(__AVR_ATmega644__) || defined(__AVR_ATmega644P__) || defined(__AVR_ATmega1284__) || defined(__AVR_ATmega1284P__)
 typedef SPi< Pb7, Pb5, Pb6, Pb4 > spi;
-#elif (defined(CORE_TEENSY) && (defined(__MK20DX128__) || defined(__MK20DX256__))) || defined(__ARDUINO_X86__) || defined(__MIPSEL__)
+#elif (defined(CORE_TEENSY) && (defined(__MK20DX128__) || defined(__MK20DX256__) || defined(__MKL26Z64__))) || defined(__ARDUINO_X86__) || defined(__MIPSEL__)
 typedef SPi< P13, P11, P12, P10 > spi;
 #elif defined(ARDUINO_SAM_DUE) && defined(__SAM3X8E__)
 typedef SPi< P76, P75, P74, P10 > spi;