Adding missing libs

.gitignore

@@ -1,4 +1 @@
-*.o
-*.a
 build
-libs

libs/mcp23s17.h

@@ -0,0 +1,180 @@
+/**
+ * @file  mcp23s17.h
+ * @brief A simple static library for controlling an MCP23S17 port
+ *        expander over SPI.
+ *
+ * Datasheet: http://ww1.microchip.com/downloads/en/devicedoc/21952b.pdf
+ *
+ * Copyright (C) 2013 Thomas Preston <[email protected]>
+ *
+ * This program is free software: 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 3 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/>.
+*/
+#ifndef _MCP23S17_H
+#define _MCP23S17_H
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+#define WRITE_CMD 0
+#define READ_CMD 1
+
+// Register addresses
+#define IODIRA 0x00  // I/O direction A
+#define IODIRB 0x01  // I/O direction B
+#define IPOLA 0x02  // I/O polarity A
+#define IPOLB 0x03  // I/O polarity B
+#define GPINTENA 0x04  // interupt enable A
+#define GPINTENB 0x05  // interupt enable B
+#define DEFVALA 0x06  // register default value A (interupts)
+#define DEFVALB 0x07  // register default value B (interupts)
+#define INTCONA 0x08  // interupt control A
+#define INTCONB 0x09  // interupt control B
+#define IOCON 0x0A  // I/O config (also 0x0B)
+#define GPPUA 0x0C  // port A pullups
+#define GPPUB 0x0D  // port B pullups
+#define INTFA 0x0E  // interupt flag A (where the interupt came from)
+#define INTFB 0x0F  // interupt flag B
+#define INTCAPA 0x10  // interupt capture A (value at interupt is saved here)
+#define INTCAPB 0x11  // interupt capture B
+#define GPIOA 0x12  // port A
+#define GPIOB 0x13  // port B
+#define OLATA 0x14  // output latch A
+#define OLATB 0x15  // output latch B
+
+// I/O config
+#define BANK_OFF 0x00  // addressing mode
+#define BANK_ON 0x80
+#define INT_MIRROR_ON 0x40  // interupt mirror (INTa|INTb)
+#define INT_MIRROR_OFF 0x00
+#define SEQOP_OFF 0x20  // incrementing address pointer
+#define SEQOP_ON 0x00
+#define DISSLW_ON 0x10  // slew rate
+#define DISSLW_OFF 0x00
+#define HAEN_ON 0x08  // hardware addressing
+#define HAEN_OFF 0x00
+#define ODR_ON 0x04  // open drain for interupts
+#define ODR_OFF 0x00
+#define INTPOL_HIGH 0x02  // interupt polarity
+#define INTPOL_LOW 0x00
+
+#define GPIO_INTERRUPT_PIN 25
+
+/**
+ * Returns a file descriptor for the SPI device through which the
+ * MCP23S17 port expander can be accessed.
+ *
+ * @param bus The SPI bus.
+ * @param chip_select The SPI chip select.
+ */
+int mcp23s17_open(int bus, int chip_select);
+
+/**
+ * Returns the 8 bit value from the register specified. Must also specify
+ * which hardware address and file descriptor to use.
+ *
+ * @param reg The register to read from (example: IODIRA, GPIOA).
+ * @param hw_addr The hardware address of the MCP23S17.
+ * @param fd The file descriptor returned from <mcp23s17_open>"()".
+ */
+uint8_t mcp23s17_read_reg(uint8_t reg, uint8_t hw_addr, int fd);
+
+/**
+ * Writes an 8 bit value to the register specified. Must also specify
+ * which hardware address and file descriptor to use.
+ *
+ * @param data The data byte to be written.
+ * @param reg The register to write to (example: IODIRA, GPIOA).
+ * @param hw_addr The hardware address of the MCP23S17.
+ * @param fd The file descriptor returned from <mcp23s17_open>"()".
+ */
+void mcp23s17_write_reg(uint8_t data, uint8_t reg, uint8_t hw_addr, int fd);
+
+/**
+ * Reads a single bit from the register specified. Must also specify
+ * which hardware address and file descriptor to use.
+ *
+ * @param bit_num The bit number to read.
+ * @param reg The register to read from (example: IODIRA, GPIOA).
+ * @param hw_addr The hardware address of the MCP23S17.
+ * @param fd The file descriptor returned from <mcp23s17_open>"()".
+ */
+uint8_t mcp23s17_read_bit(uint8_t bit_num,
+                          uint8_t reg,
+                          uint8_t hw_addr,
+                          int fd);
+
+/**
+ * Writes a single bit to the register specified. Must also specify
+ * which hardware address and file descriptor to use.
+ *
+ * @param data The data to write.
+ * @param bit_num The bit number to write to.
+ * @param reg The register to write to (example: IODIRA, GPIOA).
+ * @param hw_addr The hardware address of the MCP23S17.
+ * @param fd The file descriptor returned from <mcp23s17_open>"()".
+ */
+void mcp23s17_write_bit(uint8_t data,
+                        uint8_t bit_num,
+                        uint8_t reg,
+                        uint8_t hw_addr,
+                        int fd);
+
+
+/**
+ * Enables interrupts and exports to the GPIO connection from 
+ * the mcp23s17. 
+ *  
+ * @return int 0 on success
+ */
+int mcp23s17_enable_interrupts();
+
+
+/**
+ * Disables interrupts and exports to the GPIO connection from 
+ * the mcp23s17. 
+ *  
+ * @return int 0 on success
+ */
+int mcp23s17_disable_interrupts();
+
+
+/**
+ * Waits for an interrupt from the mcp23s17 or until timeout is 
+ * reached.  
+ * @note This method does NOT reset the interrupt - which is 
+ *       done automatically for you by reading the input state
+ *       register.  Calling this method twice in a row without
+ *       reading the input register will cause it to always wait
+ *       for your timeout value, regardless of button presses.
+ *       To avoid this, read the input register after every call
+ *       to this method.
+ *  
+ * @param timeout Maximum ms to wait for input, -1 for forever 
+ * @return the number of file descriptors ready for the 
+ *         requested I/O, zero if no file descriptor became
+ *         ready during the requested timeout milliseconds, or
+ *         -1 on error.
+ */
+int mcp23s17_wait_for_interrupt(int timeout);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif