mfd: ab8500-gpadc: Reduce conversion timeout

Reduce the conversion timeout from 2s to 0.5s
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NJonas Aaberg <jonas.aberg@stericsson.com>
Reviewed-by: NKarl KOMIEROWSKI <karl.komierowski@stericsson.com>

drivers/mfd/ab8500-gpadc.c

@@ -86,6 +86,8 @@
 /* Time in ms before disabling regulator */
 #define GPADC_AUDOSUSPEND_DELAY		1
 
+#define CONVERSION_TIME			500 /* ms */
+
 enum cal_channels {
 	ADC_INPUT_VMAIN = 0,
 	ADC_INPUT_BTEMP,
@@ -372,7 +374,8 @@ int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 channel)
 		goto out;
 	}
 	/* wait for completion of conversion */
-	if (!wait_for_completion_timeout(&gpadc->ab8500_gpadc_complete, 2*HZ)) {
+	if (!wait_for_completion_timeout(&gpadc->ab8500_gpadc_complete,
+					 msecs_to_jiffies(CONVERSION_TIME))) {
 		dev_err(gpadc->dev,
 			"timeout: didn't receive GPADC conversion interrupt\n");
 		ret = -EINVAL;