This is a preparation for adding YAS537 variant. YAS537 uses other data types on the calibration coefficients [1] than YAS530 [2] and YAS532 [3]. On YAS537, at least for a4 and a7 this could matter because 8-bit unsigned data from the register gets stored into a signed data type, therefore this should be 8-bit as well. For YAS530/532, on the other hand, it doesn't seem to matter. The size of a2-a9 and k is smaller than 8-bit at extraction, also the applied math is low. And Cx/Cy1/Cy2, now being defined as signed 16-bit, are extracted as unsigned 8-bit and undergo only minor math. [1] https://github.com/msm8916-mainline/android_kernel_qcom_msm8916/blob/GT-I9195I/drivers/iio/magnetometer/yas_mag_drv-yas537.c#L76-L78 [2] https://github.com/NovaFusion/android_kernel_samsung_golden/blob/cm-12.1/drivers/sensor/compass/yas_mag_driver-yas530.c#L526-L527 [3] https://github.com/msm8916-mainline/android_kernel_qcom_msm8916/blob/GT-I9195I/drivers/iio/magnetometer/yas_mag_drv-yas532.c#L76-L77 Cc: Linus Walleij <linus.walleij@xxxxxxxxxx> Signed-off-by: Jakob Hauser <jahau@xxxxxxxxxxxxxx> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> --- drivers/iio/magnetometer/yamaha-yas530.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/iio/magnetometer/yamaha-yas530.c b/drivers/iio/magnetometer/yamaha-yas530.c index 9bfb3b573907..31637a890b7f 100644 --- a/drivers/iio/magnetometer/yamaha-yas530.c +++ b/drivers/iio/magnetometer/yamaha-yas530.c @@ -103,9 +103,11 @@ struct yas5xx_calibration { s32 r[3]; u32 f[3]; /* Temperature compensation calibration */ - s32 Cx, Cy1, Cy2; + s16 Cx, Cy1, Cy2; /* Misc calibration coefficients */ - s32 a2, a3, a4, a5, a6, a7, a8, a9, k; + s8 a2, a3, a4, a6, a7, a8; + s16 a5, a9; + u8 k; /* clock divider */ u8 dck; }; -- 2.35.1
