Patch to add the windowing support in the libnfc

This patch enables windowing of LLC packets send from chipset to host.
The host will now wait for up to 4 LLC packets from the chipset before
sending an ACK (S-Frame RR).

Change-Id: I6a70e1d780847a104e3ec8e403593a69e222aec9

1 files changed, 131 insertions, 34 deletions

diff --git a/src/phLlcNfc_Timer.c b/src/phLlcNfc_Timer.c
index c079760..06ca7e4 100644
--- a/src/phLlcNfc_Timer.c
+++ b/src/phLlcNfc_Timer.c
@@ -44,8 +44,6 @@
 /***************************** Macros *******************************/
 /**< Timer for connection timer index */
 #define PH_LLCNFC_CONNECTION_TO_INDEX       (0x00)
-/**< 0x0A Timer for ack time out value */
-#define PH_LLCNFC_ACK_TO_VALUE              (1000)
 /**< Maximum guard timer can be present */
 #define PH_LLCNFC_MAX_GUARD_TIMER           (0x04)
 /** Connection time out bit to set */
@@ -60,6 +58,8 @@
 #define PH_LLCNFC_CON_TO_BIT_VAL            (0x01)
 /** Guard time out bit to set */
 #define PH_LLCNFC_GUARD_TO_BIT_VAL          (0x02)
+/** ACK time out bit to set */
+#define PH_LLCNFC_ACK_TO_BIT_VAL            (0x04)
 
 #define GUARD_TO_URSET
 
@@ -84,7 +84,7 @@ void
 phLlcNfc_AckTimeoutCb (
     uint32_t TimerId                    
 );
-#endif
+#endif /* #ifdef PIGGY_BACK */
 
 /* This callback is for connection time out */
 static 
@@ -290,17 +290,22 @@ phLlcNfc_StartTimers (
             /* Get the ack timer flag */
             timerstarted = (uint8_t)GET_BITS8 (
                                     ps_timer_info->timer_flag, 
-                                    PH_LLCNFC_GUARD_TO_BIT, 
+                                    PH_LLCNFC_ACK_TO_BIT,
                                     PH_LLCNFC_TO_NOOFBITS);
-            if (0 == timerstarted)
+
+            if (FALSE == timerstarted)
             {
                 /* Timer not started, so start the timer */
                 ps_timer_info->timer_flag = (uint8_t)
                                 SET_BITS8 (ps_timer_info->timer_flag, 
-                                        PH_LLCNFC_GUARD_TO_BIT
-                                        PH_LLCNFC_TO_NOOFBITS
-                                        (PH_LLCNFC_GUARD_TO_BIT - 1));
+                                        PH_LLCNFC_ACK_TO_BIT,
+                                        PH_LLCNFC_TO_NOOFBITS,
+                                        (PH_LLCNFC_ACK_TO_BIT - 1));
             }
+
+
+            timer_resolution = ps_timer_info->ack_to_value = (uint16_t)
+                                            PH_LLCNFC_ACK_TO_VALUE;
             timerid = ps_timer_info->timer_id[PH_LLCNFC_ACKTIMER];
             Callback = (ppCallBck_t)&phLlcNfc_AckTimeoutCb;
             break;
@@ -380,7 +385,7 @@ phLlcNfc_StopTimers (
             {
                 /* The number of guard timer count is more than the 
                     guard timer to delete  */
-                while (start_index < no_of_guard_to_del)
+                while (start_index < (timer_count - no_of_guard_to_del))
                 {
                     /* Copy the previous stored timer values to the present */
                     ps_timer_info->guard_to_value[start_index] = (uint16_t)
@@ -457,11 +462,14 @@ phLlcNfc_StopTimers (
 #ifdef PIGGY_BACK
         case PH_LLCNFC_ACKTIMER:
         {
+            timerflag = (timerflag & PH_LLCNFC_ACK_TO_BIT_VAL);
+
             ps_timer_info->timer_flag = (uint8_t)
                                 SET_BITS8 (ps_timer_info->timer_flag, 
-                                        PH_LLCNFC_GUARD_TO_BIT, 
+                                        PH_LLCNFC_ACK_TO_BIT,
                                         PH_LLCNFC_TO_NOOFBITS, 0);
             timerid = ps_timer_info->timer_id[PH_LLCNFC_ACKTIMER];
+            ps_timer_info->ack_to_value = 0;
             break;
         }
 #endif /* #ifdef PIGGY_BACK */
@@ -486,7 +494,7 @@ phLlcNfc_StopTimers (
 
     PHNFC_UNUSED_VARIABLE (result);
     PHNFC_UNUSED_VARIABLE (TimerType);
-    PHNFC_UNUSED_VARIABLE (no_of_gaurd_to_del);
+    PHNFC_UNUSED_VARIABLE (no_of_guard_to_del);
 
 #endif /* #ifdef LLC_TIMER_ENABLE */
 }
@@ -602,23 +610,25 @@ phLlcNfc_GuardTimeoutCb (
     NFCSTATUS                   result = NFCSTATUS_SUCCESS;
     phLlcNfc_Timerinfo_t        *ps_timer_info = NULL;
     phLlcNfc_Frame_t            *ps_frame_info = NULL;
-    phLlcNfc_LlcPacket_t        *ps_packet_info = NULL;
+    phLlcNfc_LlcPacket_t        s_packet_info;
     uint8_t                     index = 0;
+    /* zero_to_index = Time out index has become 0 */
     uint8_t                     zero_to_index = 0;
+
 #if defined (GUARD_TO_ERROR)
     phNfc_sCompletionInfo_t     notifyinfo = {0,0,0};
 #endif /* #if defined (GUARD_TO_ERROR) */
-    PHNFC_UNUSED_VARIABLE(pContext);
 
     PH_LLCNFC_PRINT("\n\nLLC : GUARD TIMEOUT CB CALLED \n\n");
 
-    if ((NULL != gpphLlcNfc_Ctxt) && (TimerId == 
-        gpphLlcNfc_Ctxt->s_timerinfo.timer_id[PH_LLCNFC_GUARDTIMER]) && 
-        (PH_LLCNFC_GUARD_TO_BIT_VAL == 
-        (gpphLlcNfc_Ctxt->s_timerinfo.timer_flag & 
+    if ((NULL != gpphLlcNfc_Ctxt) && (TimerId ==
+        gpphLlcNfc_Ctxt->s_timerinfo.timer_id[PH_LLCNFC_GUARDTIMER]) &&
+        (PH_LLCNFC_GUARD_TO_BIT_VAL ==
+        (gpphLlcNfc_Ctxt->s_timerinfo.timer_flag &
         PH_LLCNFC_GUARD_TO_BIT_VAL)))
     {
         uint8_t                 timer_expired = FALSE;
+
         ps_frame_info = &(gpphLlcNfc_Ctxt->s_frameinfo);
         ps_timer_info = &(gpphLlcNfc_Ctxt->s_timerinfo);
 
@@ -632,8 +642,15 @@ phLlcNfc_GuardTimeoutCb (
            send called */
         while (index < ps_timer_info->guard_to_count) 
         {
+            /* This loop runs for all the timer present in the data structure.
+                This means if there are 2 I frame has been sent and
+                response is not received for the I frames sent then the
+                each time this timer expires, the time out value is decremented
+                by the PH_LLCNFC_RESOLUTION value */
             if (0 != ps_timer_info->guard_to_value[index])
             {
+                /* If timer value is not zero then enter,
+                    this means that the value is not zero */
                 if (ps_timer_info->guard_to_value[index] > 0)
                 {
                     if (ps_timer_info->guard_to_value[index] >= 
@@ -651,10 +668,20 @@ phLlcNfc_GuardTimeoutCb (
 
                 if (0 == ps_timer_info->guard_to_value[index])
                 {
+                    /* Timer value has expired, so resend has to be done
+                        Timer value is 0 */
+                    ps_timer_info->frame_type[index] = (uint8_t)resend_i_frame;
+                    if (FALSE == timer_expired)
+                    {
+                        /* As the statement is in the loop, so there are possibilities
+                            of more than 1 timer value can be 0, so if previous timer
+                            value has already been 0, then again dont change the
+                            index */
                     zero_to_index = index;
                     timer_expired = TRUE;
                 }
             }
+            }
             index = (uint8_t)(index + 1);
         }
 
@@ -686,7 +713,6 @@ phLlcNfc_GuardTimeoutCb (
 
                     timer_count = ps_timer_info->guard_to_count;
 
-                    
                     /* Check before changing the index to resend, if index 
                         already exist then dont set the index */
                     while ((FALSE == while_exit) && (start_index < timer_count))
@@ -702,13 +728,29 @@ phLlcNfc_GuardTimeoutCb (
                         }
                     }
 
-                    if (TRUE == while_exit)
+                    if (FALSE == while_exit)
                     {
+                        /* This " ps_timer_info->index_to_send " member is
+                           useful, when 2 time out values are 0, then
+                           only first timed out value has to be resent and
+                           other has to wait until the the first timed out
+                           I frame is resent
+                           This statement is executed only if, none of the timer
+                           has expires previously, this is the first timer in the
+                           list that has time out value has 0
+                           */
                         ps_timer_info->index_to_send = zero_to_index;
                     }
+                    else
+                    {
+                        /* This statement is executed only if, any one of the time
+                           out value was 0 previously, so first resend has to be done
+                           for the previous I frame, so the index is set to the previous
+                           I frame
+                           */
+                        ps_timer_info->index_to_send = start_index;
+                    }
 
-                    ps_timer_info->frame_type[zero_to_index] = (uint8_t)
-                                                            resend_i_frame;
                     /* Now resend the frame stored */
                     result = phLlcNfc_H_SendTimedOutIFrame (gpphLlcNfc_Ctxt, 
                                             &(ps_frame_info->s_send_store), 
@@ -741,16 +783,15 @@ phLlcNfc_GuardTimeoutCb (
 #if (!defined (GUARD_TO_ERROR) && defined (GUARD_TO_URSET))
 
                     PH_LLCNFC_PRINT("U-RSET IS SENT \n");
-                    ps_packet_info = &(gpphLlcNfc_Ctxt->s_frameinfo.s_llcpacket);
 
-                    result = phLlcNfc_H_CreateUFramePayload(gpphLlcNfc_Ctxt, 
-                                        ps_packet_info, 
-                                        &(ps_packet_info->llcbuf_len), 
+                    result = phLlcNfc_H_CreateUFramePayload(gpphLlcNfc_Ctxt,
+                                        &(s_packet_info),
+                                        &(s_packet_info.llcbuf_len),
                                         phLlcNfc_e_rset);
 
-                    result = phLlcNfc_Interface_Write(gpphLlcNfc_Ctxt, 
-                                    (uint8_t*)&(ps_packet_info->s_llcbuf), 
-                                    (uint32_t)ps_packet_info->llcbuf_len);
+                    result = phLlcNfc_Interface_Write(gpphLlcNfc_Ctxt,
+                                    (uint8_t*)&(s_packet_info.s_llcbuf),
+                                    (uint32_t)s_packet_info.llcbuf_len);
 
                     ps_frame_info->write_status = result;
                     if (NFCSTATUS_PENDING == result)
@@ -782,15 +823,71 @@ phLlcNfc_GuardTimeoutCb (
 }
 
 #ifdef PIGGY_BACK
+
 static 
 void 
 phLlcNfc_AckTimeoutCb (
     uint32_t TimerId
 )
 {
+    NFCSTATUS                   result = NFCSTATUS_SUCCESS;
+    phLlcNfc_Frame_t            *ps_frame_info = NULL;
+    phLlcNfc_Timerinfo_t        *ps_timer_info = NULL;
+    phLlcNfc_LlcPacket_t        s_packet_info;
+
+    PH_LLCNFC_PRINT("\n\nLLC : ACK TIMEOUT CB CALLED\n\n");
 
+    if ((NULL != gpphLlcNfc_Ctxt) && (TimerId ==
+        gpphLlcNfc_Ctxt->s_timerinfo.timer_id[PH_LLCNFC_ACKTIMER])
+        && (PH_LLCNFC_ACK_TO_BIT_VAL ==
+        (gpphLlcNfc_Ctxt->s_timerinfo.timer_flag &
+        PH_LLCNFC_ACK_TO_BIT_VAL)))
+    {
+        ps_frame_info = &(gpphLlcNfc_Ctxt->s_frameinfo);
+        ps_timer_info = &(gpphLlcNfc_Ctxt->s_timerinfo);
+
+        phLlcNfc_StopTimers (PH_LLCNFC_ACKTIMER, 0);
+
+        if (NFCSTATUS_BUSY == PHNFCSTATUS (ps_frame_info->write_status))
+        {
+            /* Any how write cannot be done and some frame is ready to be sent
+            so this frame will act as the ACK */
+            result = phLlcNfc_H_WriteWaitCall (gpphLlcNfc_Ctxt);
+        }
+        else
+        {
+            /* Create S frame */
+            (void)phLlcNfc_H_CreateSFramePayload (ps_frame_info, &(s_packet_info), phLlcNfc_e_rr);
+
+            result = phLlcNfc_Interface_Write(gpphLlcNfc_Ctxt,
+                        (uint8_t *)&(s_packet_info.s_llcbuf),
+                        (uint32_t)(s_packet_info.llcbuf_len));
+
+            if (NFCSTATUS_PENDING == result)
+            {
+                if (0 == ps_frame_info->send_error_count)
+                {
+                    ps_frame_info->write_wait_call = invalid_frame;
+                }
+                ps_frame_info->sent_frame_type = s_frame;
+            }
+            else
+            {
+                if (invalid_frame == ps_frame_info->write_wait_call)
+                {
+                    ps_frame_info->write_wait_call = s_frame;
+                }
+            }
+        }
+    }
+
+    /* ACK is sent, so reset the response received count */
+    gpphLlcNfc_Ctxt->s_frameinfo.resp_recvd_count = 0;
+
+    PH_LLCNFC_PRINT("\n\nLLC : ACK TIMEOUT CB END\n\n");
 }
-#endif
+
+#endif /* #ifdef PIGGY_BACK */
 
 static 
 void 
@@ -805,7 +902,7 @@ phLlcNfc_ConnectionTimeoutCb (
     void                        *p_upperctxt = NULL;
     phLlcNfc_Frame_t            *ps_frame_info = NULL;
     phLlcNfc_Timerinfo_t        *ps_timer_info = NULL;
-    PHNFC_UNUSED_VARIABLE(pContext);
+    phLlcNfc_LlcPacket_t        s_packet_info;
     
     PH_LLCNFC_PRINT("\n\nLLC : CONNECTION TIMEOUT CB CALLED\n\n");
     if ((NULL != gpphLlcNfc_Ctxt) && (TimerId == 
@@ -834,16 +931,16 @@ phLlcNfc_ConnectionTimeoutCb (
                 {
                     /* Create a U frame */
                     result = phLlcNfc_H_CreateUFramePayload(gpphLlcNfc_Ctxt, 
-                                        &(ps_frame_info->s_llcpacket),
-                                        &(ps_frame_info->s_llcpacket.llcbuf_len), 
+                                        &(s_packet_info),
+                                        &(s_packet_info.llcbuf_len),
                                         phLlcNfc_e_rset);
 
                     if (NFCSTATUS_SUCCESS == result)
                     {
                         /* Call DAL write */
                         result = phLlcNfc_Interface_Write (gpphLlcNfc_Ctxt, 
-                                (uint8_t*)&(ps_frame_info->s_llcpacket.s_llcbuf), 
-                                (uint32_t)(ps_frame_info->s_llcpacket.llcbuf_len));
+                                (uint8_t*)&(s_packet_info.s_llcbuf),
+                                (uint32_t)(s_packet_info.llcbuf_len));
                     }
                     if (NFCSTATUS_PENDING == result)
                     {