diff options
Diffstat (limited to 'drivers/iio/light/si1133.c')
| -rw-r--r-- | drivers/iio/light/si1133.c | 37 |
1 files changed, 24 insertions, 13 deletions
diff --git a/drivers/iio/light/si1133.c b/drivers/iio/light/si1133.c index 015a21f0c2ef..9174ab928880 100644 --- a/drivers/iio/light/si1133.c +++ b/drivers/iio/light/si1133.c @@ -102,6 +102,9 @@ #define SI1133_INPUT_FRACTION_LOW 15 #define SI1133_LUX_OUTPUT_FRACTION 12 #define SI1133_LUX_BUFFER_SIZE 9 +#define SI1133_MEASURE_BUFFER_SIZE 3 + +#define SI1133_SIGN_BIT_INDEX 23 static const int si1133_scale_available[] = { 1, 2, 4, 8, 16, 32, 64, 128}; @@ -234,13 +237,13 @@ static const struct si1133_lux_coeff lux_coeff = { } }; -static int si1133_calculate_polynomial_inner(u32 input, u8 fraction, u16 mag, +static int si1133_calculate_polynomial_inner(s32 input, u8 fraction, u16 mag, s8 shift) { return ((input << fraction) / mag) << shift; } -static int si1133_calculate_output(u32 x, u32 y, u8 x_order, u8 y_order, +static int si1133_calculate_output(s32 x, s32 y, u8 x_order, u8 y_order, u8 input_fraction, s8 sign, const struct si1133_coeff *coeffs) { @@ -276,7 +279,7 @@ static int si1133_calculate_output(u32 x, u32 y, u8 x_order, u8 y_order, * The algorithm is from: * https://siliconlabs.github.io/Gecko_SDK_Doc/efm32zg/html/si1133_8c_source.html#l00716 */ -static int si1133_calc_polynomial(u32 x, u32 y, u8 input_fraction, u8 num_coeff, +static int si1133_calc_polynomial(s32 x, s32 y, u8 input_fraction, u8 num_coeff, const struct si1133_coeff *coeffs) { u8 x_order, y_order; @@ -614,7 +617,7 @@ static int si1133_measure(struct si1133_data *data, { int err; - __be16 resp; + u8 buffer[SI1133_MEASURE_BUFFER_SIZE]; err = si1133_set_adcmux(data, 0, chan->channel); if (err) @@ -625,12 +628,13 @@ static int si1133_measure(struct si1133_data *data, if (err) return err; - err = si1133_bulk_read(data, SI1133_REG_HOSTOUT(0), sizeof(resp), - (u8 *)&resp); + err = si1133_bulk_read(data, SI1133_REG_HOSTOUT(0), sizeof(buffer), + buffer); if (err) return err; - *val = be16_to_cpu(resp); + *val = sign_extend32((buffer[0] << 16) | (buffer[1] << 8) | buffer[2], + SI1133_SIGN_BIT_INDEX); return err; } @@ -704,9 +708,9 @@ static int si1133_get_lux(struct si1133_data *data, int *val) { int err; int lux; - u32 high_vis; - u32 low_vis; - u32 ir; + s32 high_vis; + s32 low_vis; + s32 ir; u8 buffer[SI1133_LUX_BUFFER_SIZE]; /* Activate lux channels */ @@ -719,9 +723,16 @@ static int si1133_get_lux(struct si1133_data *data, int *val) if (err) return err; - high_vis = (buffer[0] << 16) | (buffer[1] << 8) | buffer[2]; - low_vis = (buffer[3] << 16) | (buffer[4] << 8) | buffer[5]; - ir = (buffer[6] << 16) | (buffer[7] << 8) | buffer[8]; + high_vis = + sign_extend32((buffer[0] << 16) | (buffer[1] << 8) | buffer[2], + SI1133_SIGN_BIT_INDEX); + + low_vis = + sign_extend32((buffer[3] << 16) | (buffer[4] << 8) | buffer[5], + SI1133_SIGN_BIT_INDEX); + + ir = sign_extend32((buffer[6] << 16) | (buffer[7] << 8) | buffer[8], + SI1133_SIGN_BIT_INDEX); if (high_vis > SI1133_ADC_THRESHOLD || ir > SI1133_ADC_THRESHOLD) lux = si1133_calc_polynomial(high_vis, ir, |