[PATCH] iioc: dac: ltc2664: Fix span variable usage in ltc2664_channel_config function

From: Mohammed Anees
Date: Fri Oct 04 2024 - 09:56:31 EST


In the current implementation of the ltc2664_channel_config function,
a variable named span is declared and initialized to 0, intended to
capture the return value of the ltc2664_set_span function. However,
the output of ltc2664_set_span is directly assigned to chan->span,
leaving span unchanged. As a result, when the function later checks
if (span < 0), this condition will never trigger an error since
span remains 0, this flaw leads to ineffective error handling. The
current patch resolves this issue by checking chan->span rather than
span and also effectively removing span variable.

Signed-off-by: Mohammed Anees <pvmohammedanees2003@xxxxxxxxx>
---
drivers/iio/dac/ltc2664.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/dac/ltc2664.c b/drivers/iio/dac/ltc2664.c
index 5be5345ac5c8..64c8a51aad81 100644
--- a/drivers/iio/dac/ltc2664.c
+++ b/drivers/iio/dac/ltc2664.c
@@ -516,7 +516,7 @@ static int ltc2664_channel_config(struct ltc2664_state *st)
const struct ltc2664_chip_info *chip_info = st->chip_info;
struct device *dev = &st->spi->dev;
u32 reg, tmp[2], mspan;
- int ret, span = 0;
+ int ret;

mspan = LTC2664_MSPAN_SOFTSPAN;
ret = device_property_read_u32(dev, "adi,manual-span-operation-config",
@@ -581,8 +581,8 @@ static int ltc2664_channel_config(struct ltc2664_state *st)
if (!ret && mspan == LTC2664_MSPAN_SOFTSPAN) {
chan->span = ltc2664_set_span(st, tmp[0] / 1000,
tmp[1] / 1000, reg);
- if (span < 0)
- return dev_err_probe(dev, span,
+ if (chan->span < 0)
+ return dev_err_probe(dev, chan->span,
"Failed to set span\n");
}

@@ -590,8 +590,8 @@ static int ltc2664_channel_config(struct ltc2664_state *st)
tmp, ARRAY_SIZE(tmp));
if (!ret) {
chan->span = ltc2664_set_span(st, 0, tmp[1] / 1000, reg);
- if (span < 0)
- return dev_err_probe(dev, span,
+ if (chan->span < 0)
+ return dev_err_probe(dev, chan->span,
"Failed to set span\n");
}
}
--
2.46.0