From 9c321d9b96a08dbff8982ccc9dbb03d41dec0fae Mon Sep 17 00:00:00 2001
From: Chris Manton <cmanton@google.com>
Date: Tue, 18 Aug 2020 16:06:34 -0700
Subject: [PATCH] Remove poor placement for SCN from tACL_CB

Bug: 163134718
Tag: #refactor
Test: compile & verify basic functions working
Change-Id: I3ffe28efe945cfc8a9abc3c96d790827625b0281
---
 stack/Android.bp     |  1 +
 stack/acl/acl.h      |  6 -----
 stack/acl/btm_acl.cc | 69 ----------------------------------------------------
 3 files changed, 1 insertion(+), 75 deletions(-)

diff --git a/stack/Android.bp b/stack/Android.bp
index aab5b4411..90efb3a8c 100644
--- a/stack/Android.bp
+++ b/stack/Android.bp
@@ -120,6 +120,7 @@ cc_library_static {
         "btm/btm_sco.cc",
         "btm/btm_iso.cc",
         "btm/btm_sec.cc",
+        "btm/btm_scn.cc",
         "btu/btu_hcif.cc",
         "btu/btu_task.cc",
         "gap/gap_ble.cc",
diff --git a/stack/acl/acl.h b/stack/acl/acl.h
index a734acde7..974f82d69 100644
--- a/stack/acl/acl.h
+++ b/stack/acl/acl.h
@@ -25,8 +25,6 @@
 #include "types/bt_transport.h"
 #include "types/raw_address.h"
 
-#define BTM_MAX_SCN_ 31  // PORT_MAX_RFC_PORTS system/bt/stack/include/rfcdefs.h
-
 /* Structure returned with Role Switch information (in tBTM_CMPL_CB callback
  * function) in response to BTM_SwitchRole call.
  */
@@ -80,11 +78,9 @@ typedef struct {
  ****************************************************/
 typedef struct {
  private:
-  friend bool BTM_FreeSCN(uint8_t scn);
   friend bool BTM_IsBleConnection(uint16_t hci_handle);
   friend bool BTM_ReadPowerMode(const RawAddress& remote_bda,
                                 tBTM_PM_MODE* p_mode);
-  friend bool BTM_TryAllocateSCN(uint8_t scn);
   friend bool acl_is_role_switch_allowed();
   friend const RawAddress acl_address_from_handle(uint16_t hci_handle);
   friend int btm_pm_find_acl_ind(const RawAddress& remote_bda);
@@ -104,7 +100,6 @@ typedef struct {
   friend uint16_t acl_get_link_supervision_timeout();
   friend uint16_t acl_get_supported_packet_types();
   friend uint16_t btm_get_acl_disc_reason_code(void);
-  friend uint8_t BTM_AllocateSCN(void);
   friend uint8_t acl_get_disconnect_reason();
   friend uint8_t btm_handle_to_acl_index(uint16_t hci_handle);
   friend void BTM_SetDefaultLinkSuperTout(uint16_t timeout);
@@ -153,6 +148,5 @@ typedef struct {
   uint16_t btm_def_link_policy;
   uint16_t btm_def_link_super_tout;
   uint8_t acl_disc_reason;
-  uint8_t btm_scn[BTM_MAX_SCN_];
   uint8_t pm_pend_link;
 } tACL_CB;
diff --git a/stack/acl/btm_acl.cc b/stack/acl/btm_acl.cc
index 3261724ee..cd049d1fe 100644
--- a/stack/acl/btm_acl.cc
+++ b/stack/acl/btm_acl.cc
@@ -1573,75 +1573,6 @@ void btm_acl_role_changed(uint8_t hci_status, const RawAddress& bd_addr,
 
 /*******************************************************************************
  *
- * Function         BTM_AllocateSCN
- *
- * Description      Look through the Server Channel Numbers for a free one.
- *
- * Returns          Allocated SCN number or 0 if none.
- *
- ******************************************************************************/
-
-uint8_t BTM_AllocateSCN(void) {
-  uint8_t x;
-  BTM_TRACE_DEBUG("BTM_AllocateSCN");
-
-  // stack reserves scn 1 for HFP, HSP we still do the correct way
-  for (x = 1; x < BTM_MAX_SCN; x++) {
-    if (!btm_cb.acl_cb_.btm_scn[x]) {
-      btm_cb.acl_cb_.btm_scn[x] = true;
-      return (x + 1);
-    }
-  }
-
-  return (0); /* No free ports */
-}
-
-/*******************************************************************************
- *
- * Function         BTM_TryAllocateSCN
- *
- * Description      Try to allocate a fixed server channel
- *
- * Returns          Returns true if server channel was available
- *
- ******************************************************************************/
-
-bool BTM_TryAllocateSCN(uint8_t scn) {
-  /* Make sure we don't exceed max port range.
-   * Stack reserves scn 1 for HFP, HSP we still do the correct way.
-   */
-  if ((scn >= BTM_MAX_SCN) || (scn == 1)) return false;
-
-  /* check if this port is available */
-  if (!btm_cb.acl_cb_.btm_scn[scn - 1]) {
-    btm_cb.acl_cb_.btm_scn[scn - 1] = true;
-    return true;
-  }
-
-  return (false); /* Port was busy */
-}
-
-/*******************************************************************************
- *
- * Function         BTM_FreeSCN
- *
- * Description      Free the specified SCN.
- *
- * Returns          true or false
- *
- ******************************************************************************/
-bool BTM_FreeSCN(uint8_t scn) {
-  BTM_TRACE_DEBUG("BTM_FreeSCN ");
-  if (scn <= BTM_MAX_SCN) {
-    btm_cb.acl_cb_.btm_scn[scn - 1] = false;
-    return (true);
-  } else {
-    return (false); /* Illegal SCN passed in */
-  }
-}
-
-/*******************************************************************************
- *
  * Function         btm_set_packet_types
  *
  * Description      This function sets the packet types used for a specific
-- 
2.11.0