[PATCH 4.20 72/88] mmc: cqhci: fix space allocated for transfer descriptor

[Greg Kroah-Hartman]

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Alamy Liu <alamy.liu@xxxxxxxxx>

commit 27ec9dc17c48ea2e642ccb90b4ebf7fd47468911 upstream.

There is not enough space being allocated when DCMD is disabled.

CQE_DCMD is not necessary to be enabled when CQE is enabled.
(Software could halt CQE to send command)

In the case that CQE_DCMD is not enabled, it still needs to allocate
space for data transfer. For instance:
  CQE_DCMD is enabled:  31 slots space (one slot used by DCMD)
  CQE_DCMD is disabled: 32 slots space

Fixes: a4080225f51d ("mmc: cqhci: support for command queue enabled host")
Signed-off-by: Alamy Liu <alamy.liu@xxxxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/mmc/host/cqhci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/mmc/host/cqhci.c
+++ b/drivers/mmc/host/cqhci.c
@@ -201,7 +201,7 @@ static int cqhci_host_alloc_tdl(struct c
 	cq_host->desc_size = cq_host->slot_sz * cq_host->num_slots;
 
 	cq_host->data_size = cq_host->trans_desc_len * cq_host->mmc->max_segs *
-		(cq_host->num_slots - 1);
+		cq_host->mmc->cqe_qdepth;
 
 	pr_debug("%s: cqhci: desc_size: %zu data_sz: %zu slot-sz: %d\n",
 		 mmc_hostname(cq_host->mmc), cq_host->desc_size, cq_host->data_size,