Hello Crt Mori, The patch 764589b688a1: "iio: mlx90614: Implement filter configuration" from Aug 17, 2015, leads to the following static checker warning: drivers/iio/temperature/mlx90614.c:167 mlx90614_iir_search() warn: this cast is a no-op drivers/iio/temperature/mlx90614.c 158 ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG); 159 if (ret > 0) 160 return ret; 161 162 /* Write changed values */ 163 ret = mlx90614_write_word(client, MLX90614_CONFIG, 164 (i << MLX90614_CONFIG_IIR_SHIFT) | 165 (((u16) ((0x7 << MLX90614_CONFIG_FIR_SHIFT) | 166 ((u16) ret & (~((u16) MLX90614_CONFIG_FIR_MASK))))) & 167 (~(u16) MLX90614_CONFIG_IIR_MASK))); Quite a few of these casts make no sense. It's not clear what was intended. (~(u16) MLX90614_CONFIG_IIR_MASK) So we take int 0x7 and cast it to u16, then because of type promotion we convert it to int and do a bitwise negate. The static checker warning is because often that means (u16)~MLX90614_CONFIG_IIR_MASK is intended instead. In this case it looks like we could just remove the cast with no harm done. But why are we ANDing it with "ret" which is a negative error code??? I think there is some other typo here beyond the extra casts. 168 return ret; regards, dan carpenter -- 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
