[PATCH 21/33] dmaengine: at_hdmac: Fix impossible condition

Tudor Ambarus
2022-08-20T12:59:51Z

The iterator can not be greater than ATC_MAX_DSCR_TRIALS, as the for loop
will stop when i == ATC_MAX_DSCR_TRIALS. While here, use the common "i"
name for the iterator.

Fixes: 93dce3a6434f ("dmaengine: at_hdmac: fix residue computation")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
---
drivers/dma/at_hdmac.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index 16cea65a708d..c72c796d58bc 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -753,7 +753,8 @@ static int atc_get_bytes_left(struct dma_chan *chan, dma_cookie_t cookie)
struct at_desc *desc_first = atc_first_active(atchan);
struct at_desc *desc;
int ret;
- u32 ctrla, dscr, trials;
+ u32 ctrla, dscr;
+ unsigned int i;

/*
* If the cookie doesn't match to the currently running transfer then
@@ -823,7 +824,7 @@ static int atc_get_bytes_left(struct dma_chan *chan, dma_cookie_t cookie)
dscr = channel_readl(atchan, DSCR);
rmb(); /* ensure DSCR is read before CTRLA */
ctrla = channel_readl(atchan, CTRLA);
- for (trials = 0; trials < ATC_MAX_DSCR_TRIALS; ++trials) {
+ for (i = 0; i < ATC_MAX_DSCR_TRIALS; ++i) {
u32 new_dscr;

rmb(); /* ensure DSCR is read after CTRLA */
@@ -849,7 +850,7 @@ static int atc_get_bytes_left(struct dma_chan *chan, dma_cookie_t cookie)
rmb(); /* ensure DSCR is read before CTRLA */
ctrla = channel_readl(atchan, CTRLA);
}
- if (unlikely(trials >= ATC_MAX_DSCR_TRIALS))
+ if (unlikely(i == ATC_MAX_DSCR_TRIALS))
return -ETIMEDOUT;

/* for the first descriptor we can be more accurate */
--
2.25.1