Add struct pdb_fusb_config *cfg to fusb functions

Now the user-visible FUSB302B functions all take a struct
pdb_fusb_config * as a parameter.  The static functions don't use it
yet, but at least the public API of this code is in its finished state.

lib/include/fusb302b.h

 /*
  * Send a USB Power Delivery message to the FUSB302B
  */
-void fusb_send_message(const union pd_msg *msg);
+void fusb_send_message(struct pdb_fusb_config *cfg, const union pd_msg *msg);
 
 /*
  * Read a USB Power Delivery message from the FUSB302B
  */
-uint8_t fusb_read_message(union pd_msg *msg);
+uint8_t fusb_read_message(struct pdb_fusb_config *cfg, union pd_msg *msg);
 
 /*
  * Tell the FUSB302B to send a hard reset signal
  */
-void fusb_send_hardrst(void);
+void fusb_send_hardrst(struct pdb_fusb_config *cfg);
 
 /*
  * Read the FUSB302B status and interrupt flags into *status
  */
-void fusb_get_status(union fusb_status *status);
+void fusb_get_status(struct pdb_fusb_config *cfg, union fusb_status *status);
 
 /*
  * Read the FUSB302B BC_LVL as an enum fusb_typec_current
  */
-enum fusb_typec_current fusb_get_typec_current(void);
+enum fusb_typec_current fusb_get_typec_current(struct pdb_fusb_config *cfg);
 
 /*
  * Initialization routine for the FUSB302B
 /*
  * Reset the FUSB302B
  */
-void fusb_reset(void);
+void fusb_reset(struct pdb_fusb_config *cfg);
 
 
 #endif /* PDB_FUSB302B_H */

lib/src/fusb302b.c

     i2cMasterTransmit(&I2CD2, FUSB302B_ADDR, txbuf, size + 1, NULL, 0);
 }
 
-void fusb_send_message(const union pd_msg *msg)
+void fusb_send_message(struct pdb_fusb_config *cfg, const union pd_msg *msg)
 {
     /* Token sequences for the FUSB302B */
     static uint8_t sop_seq[5] = {
     };
 
     /* Take the I2C2 mutex now so there can't be a race condition on sop_seq */
-    i2cAcquireBus(&I2CD2);
+    i2cAcquireBus(cfg->i2cp);
 
     /* Get the length of the message: a two-octet header plus NUMOBJ four-octet
      * data objects */
     fusb_write_buf(FUSB_FIFOS, msg_len, msg->bytes);
     fusb_write_buf(FUSB_FIFOS, 4, eop_seq);
 
-    i2cReleaseBus(&I2CD2);
+    i2cReleaseBus(cfg->i2cp);
 }
 
-uint8_t fusb_read_message(union pd_msg *msg)
+uint8_t fusb_read_message(struct pdb_fusb_config *cfg, union pd_msg *msg)
 {
     uint8_t garbage[4];
     uint8_t numobj;
 
-    i2cAcquireBus(&I2CD2);
+    i2cAcquireBus(cfg->i2cp);
 
     /* If this isn't an SOP message, return error.
      * Because of our configuration, we should be able to assume this means the
     /* Throw the CRC32 in the garbage, since the PHY already checked it. */
     fusb_read_buf(FUSB_FIFOS, 4, garbage);
 
-    i2cReleaseBus(&I2CD2);
+    i2cReleaseBus(cfg->i2cp);
     return 0;
 }
 
-void fusb_send_hardrst(void)
+void fusb_send_hardrst(struct pdb_fusb_config *cfg)
 {
-    i2cAcquireBus(&I2CD2);
+    i2cAcquireBus(cfg->i2cp);
 
     /* Send a hard reset */
     fusb_write_byte(FUSB_CONTROL3, 0x07 | FUSB_CONTROL3_SEND_HARD_RESET);
 
-    i2cReleaseBus(&I2CD2);
+    i2cReleaseBus(cfg->i2cp);
 }
 
 void fusb_setup(struct pdb_fusb_config *cfg)
     i2cReleaseBus(cfg->i2cp);
 }
 
-void fusb_get_status(union fusb_status *status)
+void fusb_get_status(struct pdb_fusb_config *cfg, union fusb_status *status)
 {
-    i2cAcquireBus(&I2CD2);
+    i2cAcquireBus(cfg->i2cp);
 
     /* Read the interrupt and status flags into status */
     fusb_read_buf(FUSB_STATUS0A, 7, status->bytes);
 
-    i2cReleaseBus(&I2CD2);
+    i2cReleaseBus(cfg->i2cp);
 }
 
-enum fusb_typec_current fusb_get_typec_current(void)
+enum fusb_typec_current fusb_get_typec_current(struct pdb_fusb_config *cfg)
 {
-    i2cAcquireBus(&I2CD2);
+    i2cAcquireBus(cfg->i2cp);
 
     /* Read the BC_LVL into a variable */
     enum fusb_typec_current bc_lvl = fusb_read_byte(FUSB_STATUS0)
         & FUSB_STATUS0_BC_LVL;
 
-    i2cReleaseBus(&I2CD2);
+    i2cReleaseBus(cfg->i2cp);
 
     return bc_lvl;
 }
 
-void fusb_reset(void)
+void fusb_reset(struct pdb_fusb_config *cfg)
 {
-    i2cAcquireBus(&I2CD2);
+    i2cAcquireBus(cfg->i2cp);
 
     /* Flush the TX buffer */
     fusb_write_byte(FUSB_CONTROL0, 0x44);
     /* Reset the PD logic */
     fusb_write_byte(FUSB_RESET, FUSB_RESET_PD_RESET);
 
-    i2cReleaseBus(&I2CD2);
+    i2cReleaseBus(cfg->i2cp);
 }

lib/src/hard_reset.c

 {
     (void) cfg;
     /* Tell the PHY to send a hard reset */
-    fusb_send_hardrst();
+    fusb_send_hardrst(&cfg->fusb);
 
     return PRLHRWaitPHY;
 }

lib/src/int_n.c

         /* If the INT_N line is low */
         if (palReadLine(LINE_INT_N) == PAL_LOW) {
             /* Read the FUSB302B status and interrupt registers */
-            fusb_get_status(&status);
+            fusb_get_status(&cfg->fusb, &status);
 
             /* If the I_GCRCSENT flag is set, tell the Protocol RX thread */
             if (status.interruptb & FUSB_INTERRUPTB_I_GCRCSENT) {

lib/src/policy_engine.c

  */
 static enum policy_engine_state pe_sink_source_unresponsive(struct pdb_config *cfg)
 {
-    int tcc_match = cfg->dpm.evaluate_typec_current(cfg, fusb_get_typec_current());
+    int tcc_match = cfg->dpm.evaluate_typec_current(cfg, fusb_get_typec_current(&cfg->fusb));
 
     /* If the last two readings are the same, set the output */
     if (cfg->pe._old_tcc_match == tcc_match) {

lib/src/protocol_rx.c

          * because we have a big enough pool and are careful. */
         cfg->prl._rx_message = chPoolAlloc(&pdb_msg_pool);
         /* Read the message */
-        fusb_read_message(cfg->prl._rx_message);
+        fusb_read_message(&cfg->fusb, cfg->prl._rx_message);
         /* If it's a Soft_Reset, go to the soft reset state */
         if (PD_MSGTYPE_GET(cfg->prl._rx_message) == PD_MSGTYPE_SOFT_RESET
                 && PD_NUMOBJ_GET(cfg->prl._rx_message) == 0) {

lib/src/protocol_tx.c

 static enum protocol_tx_state protocol_tx_phy_reset(struct pdb_config *cfg)
 {
     /* Reset the PHY */
-    fusb_reset();
+    fusb_reset(&cfg->fusb);
 
     /* If a message was pending when we got here, tell the policy engine that
      * we failed to send it */
     cfg->prl._tx_message->hdr |= (cfg->prl._tx_messageidcounter % 8) << PD_HDR_MESSAGEID_SHIFT;
 
     /* Send the message to the PHY */
-    fusb_send_message(cfg->prl._tx_message);
+    fusb_send_message(&cfg->fusb, cfg->prl._tx_message);
 
     return PRLTxWaitResponse;
 }
     union pd_msg goodcrc;
 
     /* Read the GoodCRC */
-    fusb_read_message(&goodcrc);
+    fusb_read_message(&cfg->fusb, &goodcrc);
 
     /* Check that the message is correct */
     if (PD_MSGTYPE_GET(&goodcrc) == PD_MSGTYPE_GOODCRC