[PATCH v2 17/30] ufs: core: Add an argument to ufshcd_mcq_decide_queue_depth()

[Bart Van Assche <bvanassche@acm.org>]

Prepare for allocating SCSI commands in two steps by making the UFS device
queue depth an argument of ufshcd_mcq_decide_queue_depth().

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 drivers/ufs/core/ufs-mcq.c     | 14 ++++++++------
 drivers/ufs/core/ufshcd-priv.h |  2 +-
 drivers/ufs/core/ufshcd.c      |  2 +-
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/ufs/core/ufs-mcq.c b/drivers/ufs/core/ufs-mcq.c
index 4eb4f1af7800..a44ab6c010d8 100644
--- a/drivers/ufs/core/ufs-mcq.c
+++ b/drivers/ufs/core/ufs-mcq.c
@@ -132,6 +132,7 @@ EXPORT_SYMBOL_GPL(ufshcd_mcq_queue_cfg_addr);
 /**
  * ufshcd_mcq_decide_queue_depth - decide the queue depth
  * @hba: per adapter instance
+ * @ufs_dev_qd: maximum queue depth supported by the UFS device
  *
  * Return: queue-depth on success, non-zero on error
  *
@@ -140,7 +141,7 @@ EXPORT_SYMBOL_GPL(ufshcd_mcq_queue_cfg_addr);
  * Calculates and adjusts the queue depth based on the depth
  * supported by the HC and ufs device.
  */
-int ufshcd_mcq_decide_queue_depth(struct ufs_hba *hba)
+int ufshcd_mcq_decide_queue_depth(struct ufs_hba *hba, int ufs_dev_qd)
 {
 	int mac;
 
@@ -160,13 +161,14 @@ int ufshcd_mcq_decide_queue_depth(struct ufs_hba *hba)
 	if (mac < 0)
 		goto err;
 
-	WARN_ON_ONCE(!hba->dev_info.bqueuedepth);
 	/*
-	 * max. value of bqueuedepth = 256, mac is host dependent.
-	 * It is mandatory for UFS device to define bQueueDepth if
-	 * shared queuing architecture is enabled.
+	 * According to the UFS standard, the UFS device queue depth
+	 * (bQueueDepth) must be in the range 1..255 if the shared queueing
+	 * architecture is supported. bQueueDepth is zero if the shared queueing
+	 * architecture is not supported.
 	 */
-	return min_t(int, mac, hba->dev_info.bqueuedepth);
+	WARN_ON_ONCE(!ufs_dev_qd);
+	return min(mac, ufs_dev_qd);
 
 err:
 	dev_err(hba->dev, "Failed to get mac, err=%d\n", mac);
diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index d0a2c963a27d..c02f9a6af137 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -65,7 +65,7 @@ void ufshcd_compl_one_cqe(struct ufs_hba *hba, int task_tag,
 			  struct cq_entry *cqe);
 int ufshcd_mcq_init(struct ufs_hba *hba);
 void ufshcd_mcq_disable(struct ufs_hba *hba);
-int ufshcd_mcq_decide_queue_depth(struct ufs_hba *hba);
+int ufshcd_mcq_decide_queue_depth(struct ufs_hba *hba, int ufs_dev_qd);
 int ufshcd_mcq_memory_alloc(struct ufs_hba *hba);
 struct ufs_hw_queue *ufshcd_mcq_req_to_hwq(struct ufs_hba *hba,
 					   struct request *req);
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 09727a94595c..bed88caea319 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -8875,7 +8875,7 @@ static int ufshcd_alloc_mcq(struct ufs_hba *hba)
 	int ret;
 	int old_nutrs = hba->nutrs;
 
-	ret = ufshcd_mcq_decide_queue_depth(hba);
+	ret = ufshcd_mcq_decide_queue_depth(hba, hba->dev_info.bqueuedepth);
 	if (ret < 0)
 		return ret;