@@ -128,6 +128,26 @@ The current UFSHCD implementation supports following functionality,
In this version of UFSHCD Query requests and power management
functionality are not implemented.
+4. BSG Support
+------------------
+
+This transport driver supports exchanging UFS protocol information units
+(UPIUs) with an UFS device. Typically, user space will allocate
+struct ufs_bsg_request and struct ufs_bsg_reply (see ufs_bsg.h) as
+request_upiu and reply_upiu respectively. Filling those UPIUs should
+be done in accordance with JEDEC spec UFS2.1 paragraph 10.7.
+*Caveat emptor*: The driver makes no further input validations and sends the
+UPIU to the device as it is. Open the bsg device in /dev/ufs-bsg and
+send SG_IO with the applicable sg_io_v4:
+
+ io_hdr_v4.guard = 'Q';
+ io_hdr_v4.protocol = BSG_PROTOCOL_SCSI;
+ io_hdr_v4.subprotocol = BSG_SUB_PROTOCOL_SCSI_TRANSPORT;
+ io_hdr_v4.response = (__u64)reply_upiu;
+ io_hdr_v4.max_response_len = reply_len;
+ io_hdr_v4.request_len = request_len;
+ io_hdr_v4.request = (__u64)request_upiu;
+
UFS Specifications can be found at,
UFS - http://www.jedec.org/sites/default/files/docs/JESD220.pdf
UFSHCI - http://www.jedec.org/sites/default/files/docs/JESD223.pdf
@@ -109,3 +109,22 @@ config SCSI_UFS_HISI
Select this if you have UFS controller on Hisilicon chipset.
If unsure, say N.
+
+config SCSI_UFS_BSG
+ bool "Universal Flash Storage BSG device node"
+ depends on SCSI_UFSHCD
+ select BLK_DEV_BSGLIB
+ help
+ Universal Flash Storage (UFS) is SCSI transport specification for
+ accessing flash storage on digital cameras, mobile phones and
+ consumer electronic devices.
+ An UFS controller communicates with an UFS device by exchanging
+ UFS Protocol Information Units (UPIUs).
+ UPIUs can not only be used as a transport layer for the SCSI protocol
+ but are also used by the UFS native command set.
+ This transport driver supports exchanging UFS protocol information units
+ with an UFS device. See also the ufshcd driver, which is a SCSI driver
+ that supports UFS devices.
+
+ Select this if you need a bsg device node for your UFS controller.
+ If unsure, say N.
@@ -4,7 +4,8 @@ obj-$(CONFIG_SCSI_UFS_DWC_TC_PCI) += tc-dwc-g210-pci.o ufshcd-dwc.o tc-dwc-g210.
obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) += tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-dwc-g210.o
obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o
obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
-ufshcd-core-objs := ufshcd.o ufs-sysfs.o
+ufshcd-core-y += ufshcd.o ufs-sysfs.o
+ufshcd-core-$(CONFIG_SCSI_UFS_BSG) += ufs_bsg.o
obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o
obj-$(CONFIG_SCSI_UFS_HISI) += ufs-hisi.o
new file mode 100644
@@ -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;
+}
new file mode 100644
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 Western Digital Corporation
+ */
+#ifndef UFS_BSG_H
+#define UFS_BSG_H
+
+#include <linux/bsg-lib.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+
+#include "ufshcd.h"
+#include "ufs.h"
+
+#ifdef CONFIG_SCSI_UFS_BSG
+void ufs_bsg_remove(struct ufs_hba *hba);
+int ufs_bsg_probe(struct ufs_hba *hba);
+#else
+static inline void ufs_bsg_remove(struct ufs_hba *hba) {}
+static inline int ufs_bsg_probe(struct ufs_hba *hba) {return 0; }
+#endif
+
+#endif /* UFS_BSG_H */
@@ -46,6 +46,7 @@
#include "ufs_quirks.h"
#include "unipro.h"
#include "ufs-sysfs.h"
+#include "ufs_bsg.h"
#define CREATE_TRACE_POINTS
#include <trace/events/ufs.h>
@@ -6633,6 +6634,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
hba->clk_scaling.is_allowed = true;
}
+ ufs_bsg_probe(hba);
+
scsi_scan_host(hba->host);
pm_runtime_put_sync(hba->dev);
}
@@ -7854,6 +7857,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
*/
void ufshcd_remove(struct ufs_hba *hba)
{
+ ufs_bsg_remove(hba);
ufs_sysfs_remove_nodes(hba->dev);
scsi_remove_host(hba->host);
/* disable interrupts */
@@ -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 */
@@ -1,8 +1,9 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
- * TBD - UFS Transport SGIO v4 BSG Message Support
+ * UFS Transport SGIO v4 BSG Message Support
*
* Copyright (C) 2011-2013 Samsung India Software Operations
+ * Copyright (C) 2018 Western Digital Corporation
*/
#ifndef SCSI_BSG_UFS_H
#define SCSI_BSG_UFS_H
@@ -69,6 +70,33 @@ struct utp_upiu_req {
union {
struct utp_upiu_cmd sc;
struct utp_upiu_query qr;
+ struct utp_upiu_query tr;
+ /* use utp_upiu_query to host the 4 dwords of uic command */
+ struct utp_upiu_query uc;
};
};
+
+/* request (CDB) structure of the sg_io_v4 */
+struct ufs_bsg_request {
+ uint32_t msgcode;
+ struct utp_upiu_req upiu_req;
+};
+
+/* response (request sense data) structure of the sg_io_v4 */
+struct ufs_bsg_reply {
+ /*
+ * The completion result. Result exists in two forms:
+ * if negative, it is an -Exxx system errno value. There will
+ * be no further reply information supplied.
+ * else, it's the 4-byte scsi error result, with driver, host,
+ * msg and status fields. The per-msgcode reply structure
+ * will contain valid data.
+ */
+ uint32_t result;
+
+ /* If there was reply_payload, how much was received? */
+ uint32_t reply_payload_rcv_len;
+
+ struct utp_upiu_req upiu_rsp;
+};
#endif /* UFS_BSG_H */