[PATCH 3.10 41/52] iio: adc: at91: signedness bug in at91_adc_get_trigger_value_by_name()

Greg Kroah-Hartman
2014-06-24T16:38:48Z

From: Dan Carpenter <dan.carpenter@oracle.com>

commit 4f3bcd878f1d3c730fe00f619b7260c6125d49eb upstream.

at91_adc_get_trigger_value_by_name() was returning -ENOMEM truncated to
a positive u8 and that doesn't work. I've changed it to int and
refactored it to preserve the error code.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Tested-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/iio/adc/at91_adc.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -161,12 +161,11 @@ static int at91_adc_channel_init(struct
return idev->num_channels;
}

-static u8 at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
+static int at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
struct at91_adc_trigger *triggers,
const char *trigger_name)
{
struct at91_adc_state *st = iio_priv(idev);
- u8 value = 0;
int i;

for (i = 0; i < st->trigger_number; i++) {
@@ -179,15 +178,16 @@ static u8 at91_adc_get_trigger_value_by_
return -ENOMEM;

if (strcmp(trigger_name, name) == 0) {
- value = triggers[i].value;
kfree(name);
- break;
+ if (triggers[i].value == 0)
+ return -EINVAL;
+ return triggers[i].value;
}

kfree(name);
}

- return value;
+ return -EINVAL;
}

static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
@@ -197,14 +197,14 @@ static int at91_adc_configure_trigger(st
struct iio_buffer *buffer = idev->buffer;
struct at91_adc_reg_desc *reg = st->registers;
u32 status = at91_adc_readl(st, reg->trigger_register);
- u8 value;
+ int value;
u8 bit;

value = at91_adc_get_trigger_value_by_name(idev,
st->trigger_list,
idev->trig->name);
- if (value == 0)
- return -EINVAL;
+ if (value < 0)
+ return value;

if (state) {
st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL);