Input: imx6ul_tsc - propagate the errors

imx6ul_adc_init() may fail in two cases, so we should better
propagate the errors and make sure that the callers of
this function also check and propagate the errors accordingly.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/imx6ul_tsc.c

@@ -94,7 +94,7 @@ struct imx6ul_tsc {
  * TSC module need ADC to get the measure value. So
  * before config TSC, we should initialize ADC module.
  */
-static void imx6ul_adc_init(struct imx6ul_tsc *tsc)
+static int imx6ul_adc_init(struct imx6ul_tsc *tsc)
 {
 	int adc_hc = 0;
 	int adc_gc;
@@ -122,17 +122,23 @@ static void imx6ul_adc_init(struct imx6ul_tsc *tsc)
 
 	timeout = wait_for_completion_timeout
 			(&tsc->completion, ADC_TIMEOUT);
-	if (timeout == 0)
+	if (timeout == 0) {
 		dev_err(tsc->dev, "Timeout for adc calibration\n");
+		return -ETIMEDOUT;
+	}
 
 	adc_gs = readl(tsc->adc_regs + REG_ADC_GS);
-	if (adc_gs & ADC_CALF)
+	if (adc_gs & ADC_CALF) {
 		dev_err(tsc->dev, "ADC calibration failed\n");
+		return -EINVAL;
+	}
 
 	/* TSC need the ADC work in hardware trigger */
 	adc_cfg = readl(tsc->adc_regs + REG_ADC_CFG);
 	adc_cfg |= ADC_HARDWARE_TRIGGER;
 	writel(adc_cfg, tsc->adc_regs + REG_ADC_CFG);
+
+	return 0;
 }
 
 /*
@@ -188,11 +194,17 @@ static void imx6ul_tsc_set(struct imx6ul_tsc *tsc)
 	writel(start, tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
 }
 
-static void imx6ul_tsc_init(struct imx6ul_tsc *tsc)
+static int imx6ul_tsc_init(struct imx6ul_tsc *tsc)
 {
-	imx6ul_adc_init(tsc);
+	int err;
+
+	err = imx6ul_adc_init(tsc);
+	if (err)
+		return err;
 	imx6ul_tsc_channel_config(tsc);
 	imx6ul_tsc_set(tsc);
+
+	return 0;
 }
 
 static void imx6ul_tsc_disable(struct imx6ul_tsc *tsc)
@@ -311,9 +323,7 @@ static int imx6ul_tsc_open(struct input_dev *input_dev)
 		return err;
 	}
 
-	imx6ul_tsc_init(tsc);
-
-	return 0;
+	return imx6ul_tsc_init(tsc);
 }
 
 static void imx6ul_tsc_close(struct input_dev *input_dev)
@@ -491,7 +501,7 @@ static int __maybe_unused imx6ul_tsc_resume(struct device *dev)
 			goto out;
 		}
 
-		imx6ul_tsc_init(tsc);
+		retval = imx6ul_tsc_init(tsc);
 	}
 
 out: