scsi: ufs: host: mediatek: Disable auto-hibern8 during power mode changes

Disable auto-hibern8 during power mode transitions to prevent unintended
entry into auto-hibern8. Restore the original auto-hibern8 timer value
after completing the power mode change to maintain system stability and
prevent potential issues during power state transitions.

Signed-off-by: Peter Wang <peter.wang@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Author: ptr324

drivers/ufs/host/ufs-mediatek.c

@@ -1429,19 +1429,49 @@ static int ufs_mtk_pre_pwr_change(struct ufs_hba *hba,
 	return ret;
 }
 
+static int ufs_mtk_auto_hibern8_disable(struct ufs_hba *hba)
+{
+	int ret;
+
+	/* disable auto-hibern8 */
+	ufshcd_writel(hba, 0, REG_AUTO_HIBERNATE_IDLE_TIMER);
+
+	/* wait host return to idle state when auto-hibern8 off */
+	ufs_mtk_wait_idle_state(hba, 5);
+
+	ret = ufs_mtk_wait_link_state(hba, VS_LINK_UP, 100);
+	if (ret) {
+		dev_warn(hba->dev, "exit h8 state fail, ret=%d\n", ret);
+
+		ufshcd_force_error_recovery(hba);
+
+		/* trigger error handler and break suspend */
+		ret = -EBUSY;
+	}
+
+	return ret;
+}
+
 static int ufs_mtk_pwr_change_notify(struct ufs_hba *hba,
 				enum ufs_notify_change_status stage,
 				const struct ufs_pa_layer_attr *dev_max_params,
 				struct ufs_pa_layer_attr *dev_req_params)
 {
 	int ret = 0;
+	static u32 reg;
 
 	switch (stage) {
 	case PRE_CHANGE:
+		if (ufshcd_is_auto_hibern8_supported(hba)) {
+			reg = ufshcd_readl(hba, REG_AUTO_HIBERNATE_IDLE_TIMER);
+			ufs_mtk_auto_hibern8_disable(hba);
+		}
 		ret = ufs_mtk_pre_pwr_change(hba, dev_max_params,
 					     dev_req_params);
 		break;
 	case POST_CHANGE:
+		if (ufshcd_is_auto_hibern8_supported(hba))
+			ufshcd_writel(hba, reg, REG_AUTO_HIBERNATE_IDLE_TIMER);
 		break;
 	default:
 		ret = -EINVAL;
@@ -1686,29 +1716,6 @@ static void ufs_mtk_dev_vreg_set_lpm(struct ufs_hba *hba, bool lpm)
 	}
 }
 
-static int ufs_mtk_auto_hibern8_disable(struct ufs_hba *hba)
-{
-	int ret;
-
-	/* disable auto-hibern8 */
-	ufshcd_writel(hba, 0, REG_AUTO_HIBERNATE_IDLE_TIMER);
-
-	/* wait host return to idle state when auto-hibern8 off */
-	ufs_mtk_wait_idle_state(hba, 5);
-
-	ret = ufs_mtk_wait_link_state(hba, VS_LINK_UP, 100);
-	if (ret) {
-		dev_warn(hba->dev, "exit h8 state fail, ret=%d\n", ret);
-
-		ufshcd_force_error_recovery(hba);
-
-		/* trigger error handler and break suspend */
-		ret = -EBUSY;
-	}
-
-	return ret;
-}
-
 static int ufs_mtk_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op,
 	enum ufs_notify_change_status status)
 {