The value of dma_counter is set once at the start of the transfer and remains
the same until the transfer is complete. This allows the check in esp_transfer_data
to be simplified since dma_left will always be non-zero until the transfer is
completed.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
---
 hw/scsi/esp.c         | 5 ++---
 include/hw/scsi/esp.h | 3 ---
 2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c
index f38b4a2ecd..5b47d035ab 100644
--- a/hw/scsi/esp.c
+++ b/hw/scsi/esp.c
@@ -229,7 +229,6 @@ static void do_busid_cmd(ESPState *s, uint8_t *buf, uint8_t busid)
     if (datalen != 0) {
         s->rregs[ESP_RSTAT] = STAT_TC;
         s->dma_left = 0;
-        s->dma_counter = 0;
         if (datalen > 0) {
             s->rregs[ESP_RSTAT] |= STAT_DI;
         } else {
@@ -538,6 +537,7 @@ void esp_command_complete(SCSIRequest *req, uint32_t status,
 void esp_transfer_data(SCSIRequest *req, uint32_t len)
 {
     ESPState *s = req->hba_private;
+    int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
 
     assert(!s->do_cmd);
     trace_esp_transfer_data(s->dma_left, s->ti_size);
@@ -545,7 +545,7 @@ void esp_transfer_data(SCSIRequest *req, uint32_t len)
     s->async_buf = scsi_req_get_buf(req);
     if (s->dma_left) {
         esp_do_dma(s);
-    } else if (s->dma_counter != 0 && s->ti_size <= 0) {
+    } else if (to_device) {
         /*
          * If this was the last part of a DMA transfer then the
          * completion interrupt is deferred to here.
@@ -564,7 +564,6 @@ static void handle_ti(ESPState *s)
     }
 
     dmalen = esp_get_tc(s);
-    s->dma_counter = dmalen;
 
     if (s->do_cmd) {
         minlen = (dmalen < ESP_CMDBUF_SZ) ? dmalen : ESP_CMDBUF_SZ;
diff --git a/include/hw/scsi/esp.h b/include/hw/scsi/esp.h
index 60cc3047a5..b307f5d261 100644
--- a/include/hw/scsi/esp.h
+++ b/include/hw/scsi/esp.h
@@ -45,9 +45,6 @@ struct ESPState {
 
     /* The amount of data left in the current DMA transfer.  */
     uint32_t dma_left;
-    /* The size of the current DMA transfer.  Zero if no transfer is in
-       progress.  */
-    uint32_t dma_counter;
     int dma_enabled;
 
     uint32_t async_len;
-- 
2.20.1