[PATCH v4 1/5] scsi: Adjust DBD setting in mode sense for caching mode page per LLD

[Can Guo <cang@codeaurora.org>]

UFS JEDEC standards require DBD field to be set to 1 in mode sense command.
This patch allows LLD to define the setting of DBD if required.

Signed-off-by: Can Guo <cang@codeaurora.org>
---
 drivers/scsi/scsi_lib.c    | 2 ++
 include/scsi/scsi_device.h | 1 +
 2 files changed, 3 insertions(+)

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 5447738..3812e90 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2108,6 +2108,8 @@ void scsi_exit_queue(void)
 
 	memset(data, 0, sizeof(*data));
 	memset(&cmd[0], 0, 12);
+
+	dbd = sdev->set_dbd_for_ms ? 8 : dbd;
 	cmd[1] = dbd & 0x18;	/* allows DBD and LLBA bits */
 	cmd[2] = modepage;
 
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 3ed836d..f8312a3 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -172,6 +172,7 @@ struct scsi_device {
 				     * because we did a bus reset. */
 	unsigned use_10_for_rw:1; /* first try 10-byte read / write */
 	unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
+	unsigned set_dbd_for_ms:1; /* Set "DBD" field in mode sense */
 	unsigned no_report_opcodes:1;	/* no REPORT SUPPORTED OPERATION CODES */
 	unsigned no_write_same:1;	/* no WRITE SAME command */
 	unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
-- 
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