scsi: ufs-bsg: Change the calling convention for write descriptor
When we had a write descriptor query upiu, we appended the descriptor right
after the bsg request. This was fine as the bsg driver allows to allocate
whatever buffer we needed in its job request.
Still, the proper way to deliver payload, however small (we only write
config descriptors of 144 bytes), is by using the job request payload data
buffer.
So change this ABI now, while ufs-bsg is still new, and nobody is actually
using it.
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Evan Green <evgreen@chromium.org>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/Documentation/scsi/ufs.txt b/Documentation/scsi/ufs.txt
index 520b5b0..78fe7cb 100644
--- a/Documentation/scsi/ufs.txt
+++ b/Documentation/scsi/ufs.txt
@@ -147,6 +147,12 @@
io_hdr_v4.max_response_len = reply_len;
io_hdr_v4.request_len = request_len;
io_hdr_v4.request = (__u64)request_upiu;
+ if (dir == SG_DXFER_TO_DEV) {
+ io_hdr_v4.dout_xfer_len = (uint32_t)byte_cnt;
+ io_hdr_v4.dout_xferp = (uintptr_t)(__u64)buff;
+ }
+
+If you wish to write a descriptor, use the dout_xferp sg_io_v4.
UFS Specifications can be found at,
UFS - http://www.jedec.org/sites/default/files/docs/JESD220.pdf