coresight: ultrasoc-smb: Config SMB buffer before register sink

The SMB dirver register the enable/disable sysfs interface in function
smb_register_sink(), however the buffer depends on the following
configuration to work well. So it'll be possible for user to access an
unreset one.

Move the config buffer operation to before register_sink().
Ignore the return value, if smb_config_inport() fails. That will
cause the hardwares disable trace path to fail, should not affect
SMB driver remove. So we make smb_remove() return success,

Fixes: 06f5c29 ("drivers/coresight: Add UltraSoc System Memory Buffer driver")
Signed-off-by: Junhao He <[email protected]>
Reviewed-by: James Clark <[email protected]>
Signed-off-by: Suzuki K Poulose <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

drivers/hwtracing/coresight/ultrasoc-smb.c

@@ -583,37 +583,32 @@ static int smb_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	ret = smb_config_inport(dev, true);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, drvdata);
 	spin_lock_init(&drvdata->spinlock);
 	drvdata->pid = -1;
 
 	ret = smb_register_sink(pdev, drvdata);
 	if (ret) {
+		smb_config_inport(&pdev->dev, false);
 		dev_err(dev, "Failed to register SMB sink\n");
 		return ret;
 	}
 
-	ret = smb_config_inport(dev, true);
-	if (ret) {
-		smb_unregister_sink(drvdata);
-		return ret;
-	}
-
-	platform_set_drvdata(pdev, drvdata);
-
 	return 0;
 }
 
 static int smb_remove(struct platform_device *pdev)
 {
 	struct smb_drv_data *drvdata = platform_get_drvdata(pdev);
-	int ret;
-
-	ret = smb_config_inport(&pdev->dev, false);
-	if (ret)
-		return ret;
 
 	smb_unregister_sink(drvdata);
 
+	smb_config_inport(&pdev->dev, false);
+
 	return 0;
 }