[PATCH v2] scsi: ufs: Disable WriteBooster capability in non-supported UFS device

[Stanley Chu]

If UFS device is not qualified to enter the detection of WriteBooster
probing by disallowed UFS version or device quirks, then WriteBooster
capability in host shall be disabled to prevent any WriteBooster
operations in the future.

Fixes: 3d17b9b5ab11 ("scsi: ufs: Add write booster feature support")
Signed-off-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
Tested-by: Steev Klimaszewski <steev@xxxxxxxx>
Reviewed-by: Avri Altman <avri.altman@xxxxxxx>
---
 drivers/scsi/ufs/ufshcd.c | 35 +++++++++++++++++++----------------
 1 file changed, 19 insertions(+), 16 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index f173ad1bd79f..c62bd47beeaa 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6847,21 +6847,31 @@ static int ufshcd_scsi_add_wlus(struct ufs_hba *hba)
 
 static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
 {
+	struct ufs_dev_info *dev_info = &hba->dev_info;
 	u8 lun;
 	u32 d_lu_wb_buf_alloc;
 
 	if (!ufshcd_is_wb_allowed(hba))
 		return;
+	/*
+	 * Probe WB only for UFS-2.2 and UFS-3.1 (and later) devices or
+	 * UFS devices with quirk UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES
+	 * enabled
+	 */
+	if (!(dev_info->wspecversion >= 0x310 ||
+	      dev_info->wspecversion == 0x220 ||
+	     (hba->dev_quirks & UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES)))
+		goto wb_disabled;
 
 	if (hba->desc_size[QUERY_DESC_IDN_DEVICE] <
 	    DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP + 4)
 		goto wb_disabled;
 
-	hba->dev_info.d_ext_ufs_feature_sup =
+	dev_info->d_ext_ufs_feature_sup =
 		get_unaligned_be32(desc_buf +
 				   DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP);
 
-	if (!(hba->dev_info.d_ext_ufs_feature_sup & UFS_DEV_WRITE_BOOSTER_SUP))
+	if (!(dev_info->d_ext_ufs_feature_sup & UFS_DEV_WRITE_BOOSTER_SUP))
 		goto wb_disabled;
 
 	/*
@@ -6870,17 +6880,17 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
 	 * a max of 1 lun would have wb buffer configured.
 	 * Now only shared buffer mode is supported.
 	 */
-	hba->dev_info.b_wb_buffer_type =
+	dev_info->b_wb_buffer_type =
 		desc_buf[DEVICE_DESC_PARAM_WB_TYPE];
 
-	hba->dev_info.b_presrv_uspc_en =
+	dev_info->b_presrv_uspc_en =
 		desc_buf[DEVICE_DESC_PARAM_WB_PRESRV_USRSPC_EN];
 
-	if (hba->dev_info.b_wb_buffer_type == WB_BUF_MODE_SHARED) {
-		hba->dev_info.d_wb_alloc_units =
+	if (dev_info->b_wb_buffer_type == WB_BUF_MODE_SHARED) {
+		dev_info->d_wb_alloc_units =
 		get_unaligned_be32(desc_buf +
 				   DEVICE_DESC_PARAM_WB_SHARED_ALLOC_UNITS);
-		if (!hba->dev_info.d_wb_alloc_units)
+		if (!dev_info->d_wb_alloc_units)
 			goto wb_disabled;
 	} else {
 		for (lun = 0; lun < UFS_UPIU_MAX_WB_LUN_ID; lun++) {
@@ -6891,7 +6901,7 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
 					(u8 *)&d_lu_wb_buf_alloc,
 					sizeof(d_lu_wb_buf_alloc));
 			if (d_lu_wb_buf_alloc) {
-				hba->dev_info.wb_dedicated_lu = lun;
+				dev_info->wb_dedicated_lu = lun;
 				break;
 			}
 		}
@@ -6977,14 +6987,7 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
 
 	ufs_fixup_device_setup(hba);
 
-	/*
-	 * Probe WB only for UFS-3.1 devices or UFS devices with quirk
-	 * UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES enabled
-	 */
-	if (dev_info->wspecversion >= 0x310 ||
-	    dev_info->wspecversion == 0x220 ||
-	    (hba->dev_quirks & UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES))
-		ufshcd_wb_probe(hba, desc_buf);
+	ufshcd_wb_probe(hba, desc_buf);
 
 	/*
 	 * ufshcd_read_string_desc returns size of the string
-- 
2.18.0