From: Zorro Liu <lyx@rock-chips.com>
Date: Fri, 17 Jun 2016 03:43:19 +0000 (+0800)
Subject: driver, iio, mpuxxx: do nothing when fifo count is zero
X-Git-Tag: firefly_0821_release~2429
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=98827e305e4c13add79acbfc58f15bd96c09cc92;p=firefly-linux-kernel-4.4.55.git

driver, iio, mpuxxx: do nothing when fifo count is zero

if fifo count is zero, just wait for data ready, there is
no need to reset HW and SW fifo, or things may worse

Change-Id: Ie65cdfde9c4939be772861f5c0842fb66c384827
Signed-off-by: Zorro Liu <lyx@rock-chips.com>
---

diff --git a/drivers/staging/iio/imu/inv_mpu/inv_mpu_ring.c b/drivers/staging/iio/imu/inv_mpu/inv_mpu_ring.c
index d8558d75c70d..b4f15531da52 100644
--- a/drivers/staging/iio/imu/inv_mpu/inv_mpu_ring.c
+++ b/drivers/staging/iio/imu/inv_mpu/inv_mpu_ring.c
@@ -1002,8 +1002,10 @@ irqreturn_t inv_read_fifo(int irq, void *dev_id)
 		if (result)
 			goto end_session;
 		fifo_count = be16_to_cpup((__be16 *)(&data[0]));
+		/*
 		if (fifo_count == 0)
 			goto flush_fifo;
+		*/
 		if (fifo_count < bytes_per_datum)
 			goto end_session;
 		/* fifo count can't be odd number */