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dmaengine: at_hdmac: Fix impossible condition

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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: 93dce3a643 ("dmaengine: at_hdmac: fix residue computation")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-15-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Tudor Ambarus 2022-10-25 12:02:48 +03:00 committed by Vinod Koul
parent 580ee84405
commit 28cbe5a0a4
1 changed files with 4 additions and 3 deletions
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7
drivers/dma/at_hdmac.c
View file

@ -318,7 +318,8 @@ 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
@ -388,7 +389,7 @@ 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 */
@ -414,7 +415,7 @@ 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 */