dma: at_hdmac: fix invalid remaining bytes detection
Found using smatch:
drivers/dma/at_hdmac.c:299 atc_get_bytes_left() warn: unsigned
'atchan->remain_desc' is never less than zero.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index d20ab1b..ca9dd26 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -294,14 +294,16 @@
ret = -EINVAL;
goto out;
}
- atchan->remain_desc -= (desc_cur->lli.ctrla & ATC_BTSIZE_MAX)
- << (desc_first->tx_width);
- if (atchan->remain_desc < 0) {
+
+ count = (desc_cur->lli.ctrla & ATC_BTSIZE_MAX)
+ << desc_first->tx_width;
+ if (atchan->remain_desc < count) {
ret = -EINVAL;
goto out;
- } else {
- ret = atchan->remain_desc;
}
+
+ atchan->remain_desc -= count;
+ ret = atchan->remain_desc;
} else {
/*
* Get residual bytes when current