diff --git a/examples/platform/turbotjson.json b/examples/platform/turbotjson.json
index 8a7cc5d..6e9cad5 100644
--- a/examples/platform/turbotjson.json
+++ b/examples/platform/turbotjson.json
@@ -1,5 +1,5 @@
 {
-  "version": "1.0.0",
+  "version": "1.1.0",
   "platform": [
     {
       "id":300,
@@ -59,14 +59,14 @@
     { "index": 27, "rawpin": 360 }
     ],
   "I2C": [
-    { "sclpin":13, "sdapin":15, "rawpin": 0, "index": 0, "default":true }
+    { "sclpin":13, "sdapin":15, "bus": 9, "index": 0, "default":true }
     ],
   "PWM": [
     { "index":22, "rawpin":0, "chipID":0},
     { "index":24, "rawpin":0, "chipID":1 }
   ],
   "SPI": [
-    { "index":0, "chipID": 0, "clock": 11, "miso": 7, "mosi": 9, "chipselect": 5, "default": true}
+    { "index":0, "bus": 0, "slaveselect": 0, "clock": 11, "miso": 7, "mosi": 9, "chipselect": 5, "default": true}
   ],
   "UART": [
     { "index":0, "chipID":0, "rawpin":0, "path":"/dev/ttyS0", "default":true}
diff --git a/include/mraa_internal_types.h b/include/mraa_internal_types.h
index d75ec5c..f5061e8 100644
--- a/include/mraa_internal_types.h
+++ b/include/mraa_internal_types.h
@@ -35,6 +35,12 @@
 #define HAVE_PTHREAD_CANCEL
 #endif
 
+// Max count for various busses
+#define MAX_I2C_BUS_COUNT 12
+#define MAX_SPI_BUS_COUNT 12
+#define MAX_UART_COUNT 6
+
+
 // general status failures for internal functions
 #define MRAA_PLATFORM_NO_INIT -3
 #define MRAA_IO_SETUP_FAILURE -2
@@ -66,9 +72,11 @@
 #define MISO_KEY "miso"
 #define MOSI_KEY "mosi"
 #define CS_KEY "chipselect"
+#define SS_KEY "slaveselect"
 #define PIN_KEY "pin"
 #define IO_KEY "layout"
 #define PLATFORM_KEY "platform"
+#define BUS_KEY "bus"
 
 // IO keys
 #define GPIO_KEY "GPIO"
@@ -346,16 +354,16 @@ typedef struct _board_t {
     int gpio_count; /**< GPIO Count */
     int aio_count;  /**< Analog side Count */
     int i2c_bus_count; /**< Usable i2c Count */
-    mraa_i2c_bus_t  i2c_bus[12]; /**< Array of i2c */
+    mraa_i2c_bus_t  i2c_bus[MAX_I2C_BUS_COUNT]; /**< Array of i2c */
     unsigned int def_i2c_bus; /**< Position in array of default i2c bus */
     int spi_bus_count; /**< Usable spi Count */
-    mraa_spi_bus_t spi_bus[12];       /**< Array of spi */
+    mraa_spi_bus_t spi_bus[MAX_SPI_BUS_COUNT];       /**< Array of spi */
     unsigned int def_spi_bus; /**< Position in array of defult spi bus */
     unsigned int adc_raw; /**< ADC raw bit value */
     unsigned int adc_supported; /**< ADC supported bit value */
     unsigned int def_uart_dev; /**< Position in array of defult uart */
     int uart_dev_count; /**< Usable spi Count */
-    mraa_uart_dev_t uart_dev[6]; /**< Array of UARTs */
+    mraa_uart_dev_t uart_dev[MAX_UART_COUNT]; /**< Array of UARTs */
     mraa_boolean_t no_bus_mux; /**< i2c/spi/adc/pwm/uart bus muxing setup not required */
     int pwm_default_period; /**< The default PWM period is US */
     int pwm_max_period; /**< Maximum period in us */
diff --git a/src/i2c/i2c.c b/src/i2c/i2c.c
index 5de8d24..5af7526 100644
--- a/src/i2c/i2c.c
+++ b/src/i2c/i2c.c
@@ -167,7 +167,7 @@ mraa_i2c_init(int bus)
     }
     if (!board->no_bus_mux) {
         int pos = board->i2c_bus[bus].sda;
-        if (board->pins[pos].i2c.mux_total > 0) {
+        if (pos >=0 && board->pins[pos].i2c.mux_total > 0) {
             if (mraa_setup_mux_mapped(board->pins[pos].i2c) != MRAA_SUCCESS) {
                 syslog(LOG_ERR, "i2c%i_init: Failed to set-up i2c sda multiplexer", bus);
                 return NULL;
@@ -175,7 +175,7 @@ mraa_i2c_init(int bus)
         }
 
         pos = board->i2c_bus[bus].scl;
-        if (board->pins[pos].i2c.mux_total > 0) {
+        if (pos >=0 && board->pins[pos].i2c.mux_total > 0) {
             if (mraa_setup_mux_mapped(board->pins[pos].i2c) != MRAA_SUCCESS) {
                 syslog(LOG_ERR, "i2c%i_init: Failed to set-up i2c scl multiplexer", bus);
                 return NULL;
diff --git a/src/json/jsonplatform.c b/src/json/jsonplatform.c
index 25a96ce..dc40c9a 100644
--- a/src/json/jsonplatform.c
+++ b/src/json/jsonplatform.c
@@ -138,22 +138,27 @@ mraa_init_json_platform_platform(json_object* jobj_platform, mraa_board_t* board
 
     // Check to see if they've provided a UART count
     ret = mraa_init_json_platform_get_index(jobj_platform, PLATFORM_KEY, UART_COUNT_KEY, index,
-                                            &(board->uart_dev_count), 6);
+                                            &(board->uart_dev_count), MAX_UART_COUNT);
     if (ret != MRAA_SUCCESS && ret != MRAA_ERROR_NO_DATA_AVAILABLE) {
         return ret;
     }
     // Check to see if they've provided a I2C count
     ret = mraa_init_json_platform_get_index(jobj_platform, PLATFORM_KEY, I2C_COUNT_KEY, index,
-                                            &(board->i2c_bus_count), 12);
+                                            &(board->i2c_bus_count), MAX_I2C_BUS_COUNT);
     if (ret != MRAA_SUCCESS && ret != MRAA_ERROR_NO_DATA_AVAILABLE) {
         return ret;
     }
+    for (int i = 0; i < board->i2c_bus_count; ++i)
+        board->i2c_bus[i].bus_id = -1;
+
     // Check to see if they've provided a SPI count
     ret = mraa_init_json_platform_get_index(jobj_platform, PLATFORM_KEY, SPI_COUNT_KEY, index,
-                                            &(board->spi_bus_count), 12);
+                                            &(board->spi_bus_count), MAX_SPI_BUS_COUNT);
     if (ret != MRAA_SUCCESS && ret != MRAA_ERROR_NO_DATA_AVAILABLE) {
         return ret;
     }
+    for (int i = 0; i < board->spi_bus_count; ++i)
+        board->spi_bus[i].bus_id = -1;
 
     // Set the PWM default numbers
     board->pwm_default_period = -1;
@@ -278,23 +283,22 @@ mraa_init_json_platform_i2c(json_object* jobj_i2c, mraa_board_t* board, int inde
 {
     int pos = 0;
     int pin = 0;
-    int sysfs_pin = 0;
+    int bus = 0;
+    // int sysfs_pin = 0;
     mraa_result_t ret = MRAA_SUCCESS;
     json_object* jobj_temp = NULL;
 
-    // disable bus if we error out
-    board->i2c_bus[pos].bus_id = -1;
+    // Default to no mux pins defined
+    board->pins[pin].i2c.mux_total = 0;
 
     // Get the I2C bus array index
     ret = mraa_init_json_platform_get_index(jobj_i2c, I2C_KEY, INDEX_KEY, index, &pos, board->i2c_bus_count - 1);
     if (ret != MRAA_SUCCESS) {
         return ret;
     }
-    // Get the sysfs pin
-    ret = mraa_init_json_platform_get_pin(jobj_i2c, I2C_KEY, RAW_PIN_KEY, index, &sysfs_pin);
-    if (ret != MRAA_SUCCESS) {
-        return ret;
-    }
+    // Get the bus number (e.g. 2 for /dev/i2c-2). If it doesn't exist, default to bus = pos
+    bus = pos;
+    ret = mraa_init_json_platform_get_pin(jobj_i2c, I2C_KEY, BUS_KEY, index, &bus);
     // Setup the sda pin
     ret = mraa_init_json_platform_get_index(jobj_i2c, I2C_KEY, SDAPIN_KEY, index, &pin,
                                             board->phy_pin_count - 1);
@@ -302,7 +306,6 @@ mraa_init_json_platform_i2c(json_object* jobj_i2c, mraa_board_t* board, int inde
         board->i2c_bus[pos].sda = -1;
     } else if (ret == MRAA_SUCCESS) {
         board->pins[pin].capabilities.i2c = 1;
-        board->pins[pin].i2c.pinmap = sysfs_pin;
         board->i2c_bus[pos].sda = pin;
     } else {
         return ret;
@@ -314,13 +317,12 @@ mraa_init_json_platform_i2c(json_object* jobj_i2c, mraa_board_t* board, int inde
         board->i2c_bus[pos].scl = -1;
     } else if (ret == MRAA_SUCCESS) {
         board->pins[pin].capabilities.i2c = 1;
-        board->pins[pin].i2c.pinmap = sysfs_pin;
         board->i2c_bus[pos].scl = pin;
     } else {
         return ret;
     }
 
-    board->i2c_bus[pos].bus_id = pos;
+    board->i2c_bus[pos].bus_id = bus;
 
     // check to see if this i2c is the default one
     if (json_object_object_get_ex(jobj_i2c, DEFAULT_KEY, &jobj_temp)) {
@@ -369,8 +371,9 @@ mraa_result_t
 mraa_init_json_platform_spi(json_object* jobj_spi, mraa_board_t* board, int index)
 {
     int pos = 0;
+    int bus = 0;
+    int ss = 0;
     int pin = 0;
-    int parent_id = 0;
     json_object* jobj_temp = NULL;
     mraa_result_t ret = MRAA_SUCCESS;
 
@@ -380,19 +383,27 @@ mraa_init_json_platform_spi(json_object* jobj_spi, mraa_board_t* board, int inde
         return ret;
     }
 
-    // Get the parent id
-    ret = mraa_init_json_platform_get_pin(jobj_spi, SPI_KEY, CHIP_ID_KEY, index, &parent_id);
+    // Get the bus
+    ret = mraa_init_json_platform_get_pin(jobj_spi, SPI_KEY, BUS_KEY, index, &bus);
     if (ret != MRAA_SUCCESS) {
         return ret;
     }
 
+    // Get slave select
+    ret = mraa_init_json_platform_get_pin(jobj_spi, SPI_KEY, SS_KEY, index, &ss);
+    if (ret != MRAA_SUCCESS) {
+        return ret;
+    }
+
+    board->spi_bus[pos].bus_id = bus;
+    board->spi_bus[pos].slave_s = ss;
+
     // Setup the clock pin
     ret = mraa_init_json_platform_get_index(jobj_spi, SPI_KEY, CLOCK_KEY, index, &pin, board->phy_pin_count - 1);
     if (ret == MRAA_ERROR_NO_DATA_AVAILABLE) {
         board->spi_bus[pos].sclk = -1;
     } else if (ret == MRAA_SUCCESS) {
         board->pins[pin].capabilities.spi = 1;
-        board->pins[pin].spi.parent_id = parent_id;
         board->spi_bus[pos].sclk = pin;
     } else {
         return ret;
@@ -403,7 +414,6 @@ mraa_init_json_platform_spi(json_object* jobj_spi, mraa_board_t* board, int inde
         board->spi_bus[pos].miso = -1;
     } else if (ret == MRAA_SUCCESS) {
         board->pins[pin].capabilities.spi = 1;
-        board->pins[pin].spi.parent_id = parent_id;
         board->spi_bus[pos].miso = pin;
     } else {
         return ret;
@@ -414,7 +424,6 @@ mraa_init_json_platform_spi(json_object* jobj_spi, mraa_board_t* board, int inde
         board->spi_bus[pos].mosi = -1;
     } else if (ret == MRAA_SUCCESS) {
         board->pins[pin].capabilities.spi = 1;
-        board->pins[pin].spi.parent_id = parent_id;
         board->spi_bus[pos].mosi = pin;
     } else {
         return ret;
@@ -425,7 +434,6 @@ mraa_init_json_platform_spi(json_object* jobj_spi, mraa_board_t* board, int inde
         board->spi_bus[pos].cs = -1;
     } else if (ret == MRAA_SUCCESS) {
         board->pins[pin].capabilities.spi = 1;
-        board->pins[pin].spi.parent_id = parent_id;
         board->spi_bus[pos].cs = pin;
     } else {
         return ret;
diff --git a/src/spi/spi.c b/src/spi/spi.c
index e91dbf2..d571390 100644
--- a/src/spi/spi.c
+++ b/src/spi/spi.c
@@ -39,6 +39,7 @@
 #include <stdio.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <errno.h>
 
 #include "spi.h"
 #include "mraa_internal.h"
@@ -88,7 +89,7 @@ mraa_spi_init(int bus)
 
     if (!plat->no_bus_mux) {
         int pos = plat->spi_bus[bus].sclk;
-        if (plat->pins[pos].spi.mux_total > 0) {
+        if (pos >= 0 && plat->pins[pos].spi.mux_total > 0) {
             if (mraa_setup_mux_mapped(plat->pins[pos].spi) != MRAA_SUCCESS) {
                 syslog(LOG_ERR, "spi: failed to set-up spi sclk multiplexer");
                 return NULL;
@@ -96,7 +97,7 @@ mraa_spi_init(int bus)
         }
 
         pos = plat->spi_bus[bus].mosi;
-        if (plat->pins[pos].spi.mux_total > 0) {
+        if (pos >= 0 && plat->pins[pos].spi.mux_total > 0) {
             if (mraa_setup_mux_mapped(plat->pins[pos].spi) != MRAA_SUCCESS) {
                 syslog(LOG_ERR, "spi: failed to set-up spi mosi multiplexer");
                 return NULL;
@@ -104,7 +105,7 @@ mraa_spi_init(int bus)
         }
 
         pos = plat->spi_bus[bus].miso;
-        if (plat->pins[pos].spi.mux_total > 0) {
+        if (pos >= 0 && plat->pins[pos].spi.mux_total > 0) {
             if (mraa_setup_mux_mapped(plat->pins[pos].spi) != MRAA_SUCCESS) {
                 syslog(LOG_ERR, "spi: failed to set-up spi miso multiplexer");
                 return NULL;
@@ -112,7 +113,7 @@ mraa_spi_init(int bus)
         }
 
         pos = plat->spi_bus[bus].cs;
-        if (plat->pins[pos].spi.mux_total > 0) {
+        if (pos >= 0 && plat->pins[pos].spi.mux_total > 0) {
             if (mraa_setup_mux_mapped(plat->pins[pos].spi) != MRAA_SUCCESS) {
                 syslog(LOG_ERR, "spi: failed to set-up spi cs multiplexer");
                 return NULL;
@@ -158,7 +159,7 @@ mraa_spi_init_raw(unsigned int bus, unsigned int cs)
 
     dev->devfd = open(path, O_RDWR);
     if (dev->devfd < 0) {
-        syslog(LOG_ERR, "spi: Failed opening SPI Device. bus:%s", path);
+        syslog(LOG_ERR, "spi: Failed opening SPI Device. bus:%s. Error %d %s", path, errno, strerror(errno));
         status = MRAA_ERROR_INVALID_RESOURCE;
         goto init_raw_cleanup;
     }