From: Faiz Abbas <faiz_abbas@ti.com>
Date: Tue, 15 Oct 2019 12:54:34 +0000 (+0530)
Subject: scsi: Retry inquiry 3 times to overcome Unit Attention condition
X-Git-Url: http://git.dujemihanovic.xyz/?a=commitdiff_plain;h=d48f00ed11d04eb76d4510b3db1d7f36f758d4e9;p=u-boot.git

scsi: Retry inquiry 3 times to overcome Unit Attention condition

The UFS SCSI device LUNs are observed to return failure the first time a
unit ready inquiry is sent and pass on the second try. Send this
inquiry 3 times to make sure device is ready.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
---

diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index e55bb256a9..0639eb6b31 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -481,6 +481,7 @@ static int scsi_detect_dev(struct udevice *dev, int target, int lun,
 	lbaint_t capacity;
 	unsigned long blksz;
 	struct scsi_cmd *pccb = (struct scsi_cmd *)&tempccb;
+	int count, err;
 
 	pccb->target = target;
 	pccb->lun = lun;
@@ -516,9 +517,14 @@ static int scsi_detect_dev(struct udevice *dev, int target, int lun,
 	dev_desc->target = pccb->target;
 	dev_desc->lun = pccb->lun;
 
-	pccb->datalen = 0;
-	scsi_setup_test_unit_ready(pccb);
-	if (scsi_exec(dev, pccb)) {
+	for (count = 0; count < 3; count++) {
+		pccb->datalen = 0;
+		scsi_setup_test_unit_ready(pccb);
+		err = scsi_exec(dev, pccb);
+		if (!err)
+			break;
+	}
+	if (err) {
 		if (dev_desc->removable) {
 			dev_desc->type = perq;
 			goto removable;