From df032bf27a414acf61c957ec2fad22a57d903b39 Mon Sep 17 00:00:00 2001 From: Avri Altman Date: Sun, 7 Oct 2018 17:30:35 +0300 Subject: scsi: ufs: Add a bsg endpoint that supports UPIUs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit For now, just provide an API to allocate and remove ufs-bsg node. We will use this framework to manage ufs devices by sending UPIU transactions. For the time being, implements an empty bsg_request() - will add some more functionality in coming patches. Nonetheless, we reveal here the protocol we are planning to use: UFS Transport Protocol Transactions. UFS transactions consist of packets called UFS Protocol Information Units (UPIU). There are UPIU’s defined for UFS SCSI commands, responses, data in and data out, task management, utility functions, vendor functions, transaction synchronization and control, and more. By using UPIUs, we get access to the most fine-grained internals of this protocol, and able to communicate with the device in ways, that are sometimes beyond the capacity of the ufs driver. Moreover and as a result, our core structure - ufs_bsg_node has a pretty lean structure: using upiu transactions that contains the outmost detailed info, so we don't really need complex constructs to support it. Signed-off-by: Avri Altman Reviewed-by: Christoph Hellwig Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen --- drivers/scsi/ufs/ufshcd.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/scsi/ufs/ufshcd.h') diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index 33fdd3f281ae..54e6fe87954f 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -702,6 +702,9 @@ struct ufs_hba { struct rw_semaphore clk_scaling_lock; struct ufs_desc_size desc_size; atomic_t scsi_block_reqs_cnt; + + struct device bsg_dev; + struct request_queue *bsg_queue; }; /* Returns true if clocks can be gated. Otherwise false */ -- cgit