scsi: ufs: mediatek: Add UFS_MTK_CAP_DISABLE_MCQ

Add new mediatek host cap UFS_MTK_CAP_DISABLE_MCQ to allow disabling MCQ
feature by assigning dts boolean property "mediatek,ufs-disable-mcq".
Signed-off-by: Po-Wen Kao <powen.kao@mediatek.com>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Acked-by: Chun-Hung Wu <Chun-Hung.Wu@mediatek.com>
Signed-off-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20240315083448.7185-4-peter.wang@mediatek.comSigned-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/ufs/host/ufs-mediatek.c

@@ -639,6 +639,9 @@ static void ufs_mtk_init_host_caps(struct ufs_hba *hba)
 	if (of_property_read_bool(np, "mediatek,ufs-tx-skew-fix"))
 		host->caps |= UFS_MTK_CAP_TX_SKEW_FIX;
 
+	if (of_property_read_bool(np, "mediatek,ufs-disable-mcq"))
+		host->caps |= UFS_MTK_CAP_DISABLE_MCQ;
+
 	dev_info(hba->dev, "caps: 0x%x", host->caps);
 }
 
@@ -902,6 +905,9 @@ static void ufs_mtk_init_mcq_irq(struct ufs_hba *hba)
 	host->mcq_nr_intr = UFSHCD_MAX_Q_NR;
 	pdev = container_of(hba->dev, struct platform_device, dev);
 
+	if (host->caps & UFS_MTK_CAP_DISABLE_MCQ)
+		goto failed;
+
 	for (i = 0; i < host->mcq_nr_intr; i++) {
 		/* irq index 0 is legacy irq, sq/cq irq start from index 1 */
 		irq = platform_get_irq(pdev, i + 1);
@@ -1617,6 +1623,12 @@ static int ufs_mtk_clk_scale_notify(struct ufs_hba *hba, bool scale_up,
 
 static int ufs_mtk_get_hba_mac(struct ufs_hba *hba)
 {
+	struct ufs_mtk_host *host = ufshcd_get_variant(hba);
+
+	/* MCQ operation not permitted */
+	if (host->caps & UFS_MTK_CAP_DISABLE_MCQ)
+		return -EPERM;
+
 	return MAX_SUPP_MAC;
 }
 

drivers/ufs/host/ufs-mediatek.h

@@ -143,6 +143,7 @@ enum ufs_mtk_host_caps {
 	UFS_MTK_CAP_ALLOW_VCCQX_LPM            = 1 << 5,
 	UFS_MTK_CAP_PMC_VIA_FASTAUTO           = 1 << 6,
 	UFS_MTK_CAP_TX_SKEW_FIX                = 1 << 7,
+	UFS_MTK_CAP_DISABLE_MCQ                = 1 << 8,
 };
 
 struct ufs_mtk_crypt_cfg {