[PATCH 1/3] scsi: ufs: add quirk to handle broken UIC command

From: jongmin jeong <jjmin.jeong@samsung.com>
To: jejb@linux.ibm.com, martin.petersen@oracle.com
Cc: alim.akhtar@samsung.com, avri.altman@wdc.com,
	cang@codeaurora.org, beanhuo@micron.com, adrian.hunter@intel.com,
	linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
	jjmin.jeong@samsung.com
Subject: [PATCH 1/3] scsi: ufs: add quirk to handle broken UIC command
Date: Thu, 27 May 2021 12:08:59 +0900	[thread overview]
Message-ID: <20210527030901.88403-2-jjmin.jeong@samsung.com> (raw)
In-Reply-To: <20210527030901.88403-1-jjmin.jeong@samsung.com>

samsung ExynosAuto SoC has two types of host controller interface to
support the virtualization of UFS Device.
One is the physical host(PH) that the same as conventaional UFSHCI,
and the other is the virtual host(VH) that support data transfer function only.

In this structure, the virtual host does not support UIC command.
To support this, we add the quirk and return 0 when the UIC command
send function is called.

Change-Id: Ie528726b29bcb643149440bf1c90eaa5995c5ac1
Signed-off-by: jongmin jeong <jjmin.jeong@samsung.com>
---
 drivers/scsi/ufs/ufshcd.c | 3 +++
 drivers/scsi/ufs/ufshcd.h | 6 ++++++
 2 files changed, 9 insertions(+)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 4ba3bbf14df0..ec663cb58233 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2318,6 +2318,9 @@ int ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd)
 	int ret;
 	unsigned long flags;
 
+	if (hba->quirks & UFSHCD_QUIRK_BROKEN_UIC_CMD)
+		return 0;
+
 	ufshcd_hold(hba, false);
 	mutex_lock(&hba->uic_cmd_mutex);
 	ufshcd_add_delay_before_dme_cmd(hba);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 0f0e62bfdafd..4a929bf7cf8e 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -569,6 +569,12 @@ enum ufshcd_quirks {
 	 * This quirk allows only sg entries aligned with page size.
 	 */
 	UFSHCD_QUIRK_ALIGN_SG_WITH_PAGE_SIZE		= 1 << 14,
+
+	/*
+	 * This quirk needs to be enabled if the host controller does not
+	 * support UIC command
+	 */
+	UFSHCD_QUIRK_BROKEN_UIC_CMD			= 1 << 15,
 };
 
 enum ufshcd_caps {
-- 
2.31.1

