1 files changed, 93 insertions, 0 deletions
diff --git a/drivers/scsi/ufs/ufs_bsg.c b/drivers/scsi/ufs/ufs_bsg.c
new file mode 100644
index 000000000000..1036c520d349
--- /dev/null
+++ b/drivers/scsi/ufs/ufs_bsg.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * bsg endpoint that supports UPIUs
+ *
+ * Copyright (C) 2018 Western Digital Corporation
+ */
+#include "ufs_bsg.h"
+
+
+static int ufs_bsg_request(struct bsg_job *job)
+{
+	struct ufs_bsg_request *bsg_request = job->request;
+	struct ufs_bsg_reply *bsg_reply = job->reply;
+	int ret = -ENOTSUPP;
+
+	bsg_reply->reply_payload_rcv_len = 0;
+
+	/* Do Nothing for now */
+	dev_err(job->dev, "unsupported message_code 0x%x\n",
+		bsg_request->msgcode);
+
+	bsg_reply->result = ret;
+	job->reply_len = sizeof(struct ufs_bsg_reply) +
+			 bsg_reply->reply_payload_rcv_len;
+
+	bsg_job_done(job, ret, bsg_reply->reply_payload_rcv_len);
+
+	return ret;
+}
+
+/**
+ * ufs_bsg_remove - detach and remove the added ufs-bsg node
+ *
+ * Should be called when unloading the driver.
+ */
+void ufs_bsg_remove(struct ufs_hba *hba)
+{
+	struct device *bsg_dev = &hba->bsg_dev;
+
+	if (!hba->bsg_queue)
+		return;
+
+	bsg_unregister_queue(hba->bsg_queue);
+
+	device_del(bsg_dev);
+	put_device(bsg_dev);
+}
+
+static inline void ufs_bsg_node_release(struct device *dev)
+{
+	put_device(dev->parent);
+}
+
+/**
+ * ufs_bsg_probe - Add ufs bsg device node
+ * @hba: per adapter object
+ *
+ * Called during initial loading of the driver, and before scsi_scan_host.
+ */
+int ufs_bsg_probe(struct ufs_hba *hba)
+{
+	struct device *bsg_dev = &hba->bsg_dev;
+	struct Scsi_Host *shost = hba->host;
+	struct device *parent = &shost->shost_gendev;
+	struct request_queue *q;
+	int ret;
+
+	device_initialize(bsg_dev);
+
+	bsg_dev->parent = get_device(parent);
+	bsg_dev->release = ufs_bsg_node_release;
+
+	dev_set_name(bsg_dev, "ufs-bsg");
+
+	ret = device_add(bsg_dev);
+	if (ret)
+		goto out;
+
+	q = bsg_setup_queue(bsg_dev, dev_name(bsg_dev), ufs_bsg_request, 0);
+	if (IS_ERR(q)) {
+		ret = PTR_ERR(q);
+		goto out;
+	}
+
+	hba->bsg_queue = q;
+
+	return 0;
+
+out:
+	dev_err(bsg_dev, "fail to initialize a bsg dev %d\n", shost->host_no);
+	put_device(bsg_dev);
+	return ret;
+}