Added main library header file

For now, the new <pdb.h> file only has a function to start the library,
based on the old start_pd function from main.c.  It'll eventually be all
a user needs to include, but there's a lot more refactoring to do.

lib/include/pdb.h

@@ -0,0 +1,29 @@
+/*
+ * PD Buddy - USB Power Delivery for everyone
+ * Copyright (C) 2017 Clayton G. Hobbs <clay@lakeserv.net>
+ *
+ * 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 PDB_H
+#define PDB_H
+
+
+/*
+ * Initialize the PD Buddy firmware library, starting all its threads
+ */
+void pdb_init(void);
+
+
+#endif /* PDB_H */

lib/src/pdb.c

@@ -0,0 +1,43 @@
+/*
+ * PD Buddy - USB Power Delivery for everyone
+ * Copyright (C) 2017 Clayton G. Hobbs <clay@lakeserv.net>
+ *
+ * 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/>.
+ */
+
+#include <pdb.h>
+#include "policy_engine.h"
+#include "protocol_rx.h"
+#include "protocol_tx.h"
+#include "hard_reset.h"
+#include "int_n.h"
+#include "fusb302b.h"
+
+
+void pdb_init(void)
+{
+    /* Initialize the FUSB302B */
+    fusb_setup();
+
+    /* Create the policy engine thread. */
+    pdb_pe_run();
+
+    /* Create the protocol layer threads. */
+    pdb_prlrx_run();
+    pdb_prltx_run();
+    pdb_hardrst_run();
+
+    /* Create the INT_N thread. */
+    pdb_int_n_run();
+}

src/main.c

@@ -40,14 +40,9 @@
 #include "shell.h"
 #include "usbcfg.h"
 
+#include <pdb.h>
 #include "led.h"
 #include "device_policy_manager.h"
-#include "policy_engine.h"
-#include "protocol_tx.h"
-#include "protocol_rx.h"
-#include "hard_reset.h"
-#include "int_n.h"
-#include "fusb302b.h"
 #include "messages.h"
 
 /*
@@ -61,29 +56,6 @@ static const I2CConfig i2c2config = {
     0
 };
 
-/*
- * Start the USB Power Delivery threads
- */
-static void start_pd(void)
-{
-    /* Start I2C2 to make communication with the PHY possible */
-    i2cStart(&I2CD2, &i2c2config);
-
-    /* Initialize the FUSB302B */
-    fusb_setup();
-
-    /* Create the policy engine thread. */
-    pdb_pe_run();
-
-    /* Create the protocol layer threads. */
-    pdb_prlrx_run();
-    pdb_prltx_run();
-    pdb_hardrst_run();
-
-    /* Create the INT_N thread. */
-    pdb_int_n_run();
-}
-
 /*
  * Enter setup mode
  */
@@ -95,7 +67,7 @@ static void setup(void)
     pdb_dpm_usb_comms = true;
 
     /* Start the USB Power Delivery threads */
-    start_pd();
+    pdb_init();
 
     /* Indicate that we're in setup mode */
     chEvtSignal(pdb_led_thread, PDB_EVT_LED_CONFIG);
@@ -122,7 +94,7 @@ static void setup(void)
 static void sink(void)
 {
     /* Start the USB Power Delivery threads */
-    start_pd();
+    pdb_init();
 
     /* Wait, letting all the other threads do their work. */
     while (true) {
@@ -151,6 +123,9 @@ int main(void) {
     /* Create the LED thread. */
     pdb_led_run();
 
+    /* Start I2C2 to make communication with the PHY possible */
+    i2cStart(&I2CD2, &i2c2config);
+
     /* Decide what mode to enter by the state of the button */
     if (palReadLine(LINE_BUTTON) == PAL_HIGH) {
         /* Button pressed -> setup mode */