From 1de953e77b8c8b8cb6f734733cf20e95a1b0fbb8 Mon Sep 17 00:00:00 2001 From: Crt Mori Date: Fri, 2 Oct 2015 14:24:21 +0200 Subject: [PATCH] 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 Signed-off-by: Crt Mori Signed-off-by: Jonathan Cameron --- drivers/iio/temperature/mlx90614.c | 14 ++++++++------ 1 file 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; } -- 2.39.5