Driver was reporting invalid raw read values for MAX6675 on big
endian architectures. MAX6675 buffered mode is not affected, nor
is the MAX31855.
The driver was losing a 2 byte read value when it used a 32 bit
integer buffer to store a 16 bit big endian value. Use big endian
types to properly align buffers on big endian architectures.
Fixes following sparse endianness warnings:
warning: cast to restricted __be16
warning: cast to restricted __be32
Fixes checkpatch issue:
CHECK: No space is necessary after a cast
Signed-off-by: sayli karnik <karniksayli1995@xxxxxxxxx>
Fixes: 1f25ca11d84a ("iio: temperature: add support for Maxim
thermocouple chips")
---
Changes in v4:
Reverted back to v2 with changed names for buffers
Changes in v3:
Updated the commit message
Updated the changelog to include explanation to the bug fix
Fixed the checkpatch issue: CHECK: No space is necessary after a cast
Added the fixes tag
drivers/iio/temperature/maxim_thermocouple.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/drivers/iio/temperature/maxim_thermocouple.c b/drivers/iio/temperature/maxim_thermocouple.c
index 39dd202..066161a 100644
--- a/drivers/iio/temperature/maxim_thermocouple.c
+++ b/drivers/iio/temperature/maxim_thermocouple.c
@@ -123,22 +123,24 @@ static int maxim_thermocouple_read(struct maxim_thermocouple_data *data,
{
unsigned int storage_bytes = data->chip->read_size;
unsigned int shift = chan->scan_type.shift + (chan->address * 8);
- unsigned int buf;
+ __be16 buf16;
+ __be32 buf32;
int ret;
- ret = spi_read(data->spi, (void *) &buf, storage_bytes);
- if (ret)
- return ret;
-
switch (storage_bytes) {
case 2:
- *val = be16_to_cpu(buf);
+ ret = spi_read(data->spi, (void *)&buf16, storage_bytes);
+ *val = be16_to_cpu(buf16);
break;
case 4:
- *val = be32_to_cpu(buf);
+ ret = spi_read(data->spi, (void *)&buf32, storage_bytes);
+ *val = be32_to_cpu(buf32);
break;
}
+ if (ret)
+ return ret;
+
/* check to be sure this is a valid reading */
if (*val & data->chip->status_bit)
return -EINVAL;
--
2.7.4
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
