staging:iio:accel:sca3000 add readback of the 3db low pass filter frequency

Driving towards getting rid of the non standard mode control interface.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>

diff --git a/drivers/staging/iio/accel/sca3000.c b/drivers/staging/iio/accel/sca3000.c
index 86b0f10..8aa6980 100644 (file)
--- a/drivers/staging/iio/accel/sca3000.c
+++ b/drivers/staging/iio/accel/sca3000.c
@@ -191,10 +191,13 @@ struct sca3000_chip_info {
        unsigned int            scale;
        bool                    temp_output;
        int                     measurement_mode_freq;
+       int                     measurement_mode_3db_freq;
        int                     option_mode_1;
        int                     option_mode_1_freq;
+       int                     option_mode_1_3db_freq;
        int                     option_mode_2;
        int                     option_mode_2_freq;
+       int                     option_mode_2_3db_freq;
        int                     mot_det_mult_xz[6];
        int                     mot_det_mult_y[7];
 };
@@ -219,36 +222,46 @@ static const struct sca3000_chip_info sca3000_spi_chip_info_tbl[] = {
                .scale = 7357,
                .temp_output = true,
                .measurement_mode_freq = 250,
+               .measurement_mode_3db_freq = 45,
                .option_mode_1 = SCA3000_OP_MODE_BYPASS,
                .option_mode_1_freq = 250,
+               .option_mode_1_3db_freq = 70,
                .mot_det_mult_xz = {50, 100, 200, 350, 650, 1300},
                .mot_det_mult_y = {50, 100, 150, 250, 450, 850, 1750},
        },
        [e02] = {
                .scale = 9810,
                .measurement_mode_freq = 125,
+               .measurement_mode_3db_freq = 40,
                .option_mode_1 = SCA3000_OP_MODE_NARROW,
                .option_mode_1_freq = 63,
+               .option_mode_1_3db_freq = 11,
                .mot_det_mult_xz = {100, 150, 300, 550, 1050, 2050},
                .mot_det_mult_y = {50, 100, 200, 350, 700, 1350, 2700},
        },
        [e04] = {
                .scale = 19620,
                .measurement_mode_freq = 100,
+               .measurement_mode_3db_freq = 38,
                .option_mode_1 = SCA3000_OP_MODE_NARROW,
                .option_mode_1_freq = 50,
+               .option_mode_1_3db_freq = 9,
                .option_mode_2 = SCA3000_OP_MODE_WIDE,
                .option_mode_2_freq = 400,
+               .option_mode_2_3db_freq = 70,
                .mot_det_mult_xz = {200, 300, 600, 1100, 2100, 4100},
                .mot_det_mult_y = {100, 200, 400, 7000, 1400, 2700, 54000},
        },
        [e05] = {
                .scale = 61313,
                .measurement_mode_freq = 200,
+               .measurement_mode_3db_freq = 60,
                .option_mode_1 = SCA3000_OP_MODE_NARROW,
                .option_mode_1_freq = 50,
+               .option_mode_1_3db_freq = 9,
                .option_mode_2 = SCA3000_OP_MODE_WIDE,
                .option_mode_2_freq = 400,
+               .option_mode_2_3db_freq = 75,
                .mot_det_mult_xz = {600, 900, 1700, 3200, 6100, 11900},
                .mot_det_mult_y = {300, 600, 1200, 2000, 4100, 7800, 15600},
        },
@@ -578,7 +591,8 @@ static const struct iio_event_spec sca3000_event = {
                .modified = 1,                                  \
                .channel2 = mod,                                \
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
-               .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
+               .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |\
+                       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),\
                .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
                .address = index,                               \
                .scan_index = index,                            \
@@ -738,6 +752,33 @@ static int write_raw_samp_freq(struct sca3000_state *st, int val)
                                     ctrlval);
 }
 
+static int sca3000_read_3db_freq(struct sca3000_state *st, int *val)
+{
+       int ret;
+
+       ret = sca3000_read_data_short(st, SCA3000_REG_MODE_ADDR, 1);
+       if (ret)
+               return ret;
+
+       /* mask bottom 2 bits - only ones that are relevant */
+       st->rx[0] &= SCA3000_REG_MODE_MODE_MASK;
+       switch (st->rx[0]) {
+       case SCA3000_REG_MODE_MEAS_MODE_NORMAL:
+               *val = st->info->measurement_mode_3db_freq;
+               return IIO_VAL_INT;
+       case SCA3000_REG_MODE_MEAS_MODE_MOT_DET:
+               return -EBUSY;
+       case SCA3000_REG_MODE_MEAS_MODE_OP_1:
+               *val = st->info->option_mode_1_3db_freq;
+               return IIO_VAL_INT;
+       case SCA3000_REG_MODE_MEAS_MODE_OP_2:
+               *val = st->info->option_mode_2_3db_freq;
+               return IIO_VAL_INT;
+       default:
+               return -EINVAL;
+       }
+}
+
 static int sca3000_read_raw(struct iio_dev *indio_dev,
                            struct iio_chan_spec const *chan,
                            int *val,
@@ -795,6 +836,11 @@ static int sca3000_read_raw(struct iio_dev *indio_dev,
                ret = read_raw_samp_freq(st, val);
                mutex_unlock(&st->lock);
                return ret ? ret : IIO_VAL_INT;
+       case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+               mutex_lock(&st->lock);
+               ret = sca3000_read_3db_freq(st, val);
+               mutex_unlock(&st->lock);
+               return ret;
        default:
                return -EINVAL;
        }