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authorCrt Mori <cmo@melexis.com>2015-10-02 15:24:21 +0300
committerJonathan Cameron <jic23@kernel.org>2015-10-03 12:15:25 +0300
commit1de953e77b8c8b8cb6f734733cf20e95a1b0fbb8 (patch)
treea482c774bd4097f91bff9a84f6aa061be16106ff /drivers/iio/temperature/mlx90614.c
parentc05dc2cce7422a5c05db470572b22fcd855f8cd7 (diff)
downloadlinux-1de953e77b8c8b8cb6f734733cf20e95a1b0fbb8.tar.xz
iio: mlx96014: Error checking from positive to negative
Dan Carpenter reported a static checker report and after his mail I noticed that we actually return from function if positive value is obtained from i2c read. This was remainder from when code was not in separate function (which I changed during the review process). Static checker reported drivers/iio/temperature/mlx90614.c:167 mlx90614_iir_search() warn: this cast is a no-op which meant that cast before negating is useless. Dan also proposed a solution on nicer bit operation form. Also changed magic number to macro in process as that was confusing. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Crt Mori <cmo@melexis.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Diffstat (limited to 'drivers/iio/temperature/mlx90614.c')
-rw-r--r--drivers/iio/temperature/mlx90614.c14
1 files changed, 8 insertions, 6 deletions
diff --git a/drivers/iio/temperature/mlx90614.c b/drivers/iio/temperature/mlx90614.c
index 3fd3ba426a84..a570c2e2aac3 100644
--- a/drivers/iio/temperature/mlx90614.c
+++ b/drivers/iio/temperature/mlx90614.c
@@ -72,6 +72,7 @@
#define MLX90614_CONST_SCALE 20 /* Scale in milliKelvin (0.02 * 1000) */
#define MLX90614_CONST_RAW_EMISSIVITY_MAX 65535 /* max value for emissivity */
#define MLX90614_CONST_EMISSIVITY_RESOLUTION 15259 /* 1/65535 ~ 0.000015259 */
+#define MLX90614_CONST_FIR 0x7 /* Fixed value for FIR part of low pass filter */
struct mlx90614_data {
struct i2c_client *client;
@@ -156,15 +157,16 @@ static inline s32 mlx90614_iir_search(const struct i2c_client *client,
* changes
*/
ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
- if (ret > 0)
+ if (ret < 0)
return ret;
+ ret &= ~MLX90614_CONFIG_FIR_MASK;
+ ret |= MLX90614_CONST_FIR << MLX90614_CONFIG_FIR_SHIFT;
+ ret &= ~MLX90614_CONFIG_IIR_MASK;
+ ret |= i << MLX90614_CONFIG_IIR_SHIFT;
+
/* Write changed values */
- ret = mlx90614_write_word(client, MLX90614_CONFIG,
- (i << MLX90614_CONFIG_IIR_SHIFT) |
- (((u16) ((0x7 << MLX90614_CONFIG_FIR_SHIFT) |
- ((u16) ret & (~((u16) MLX90614_CONFIG_FIR_MASK))))) &
- (~(u16) MLX90614_CONFIG_IIR_MASK)));
+ ret = mlx90614_write_word(client, MLX90614_CONFIG, ret);
return ret;
}