diff options
Diffstat (limited to 'drivers/staging/iio/resolver/ad2s1210.c')
-rw-r--r-- | drivers/staging/iio/resolver/ad2s1210.c | 191 |
1 files changed, 183 insertions, 8 deletions
diff --git a/drivers/staging/iio/resolver/ad2s1210.c b/drivers/staging/iio/resolver/ad2s1210.c index 4d651a2d0f38..12437f697f79 100644 --- a/drivers/staging/iio/resolver/ad2s1210.c +++ b/drivers/staging/iio/resolver/ad2s1210.c @@ -443,6 +443,123 @@ static int ad2s1210_set_phase_lock_range(struct ad2s1210_state *st, return ret; } +/* map resolution to microradians/LSB for LOT registers */ +static const int ad2s1210_lot_threshold_urad_per_lsb[] = { + 6184, /* 10-bit: ~0.35 deg/LSB, 45 deg max */ + 2473, /* 12-bit: ~0.14 deg/LSB, 18 deg max */ + 1237, /* 14-bit: ~0.07 deg/LSB, 9 deg max */ + 1237, /* 16-bit: same as 14-bit */ +}; + +static int ad2s1210_get_lot_high_threshold(struct ad2s1210_state *st, + int *val, int *val2) +{ + unsigned int reg_val; + int ret; + + mutex_lock(&st->lock); + ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, ®_val); + mutex_unlock(&st->lock); + + if (ret < 0) + return ret; + + *val = 0; + *val2 = reg_val * ad2s1210_lot_threshold_urad_per_lsb[st->resolution]; + return IIO_VAL_INT_PLUS_MICRO; +} + +static int ad2s1210_set_lot_high_threshold(struct ad2s1210_state *st, + int val, int val2) +{ + unsigned int high_reg_val, low_reg_val, hysteresis; + int ret; + + /* all valid values are between 0 and pi/4 radians */ + if (val != 0) + return -EINVAL; + + mutex_lock(&st->lock); + /* + * We need to read both high and low registers first so we can preserve + * the hysteresis. + */ + ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, &high_reg_val); + if (ret < 0) + goto error_ret; + + ret = regmap_read(st->regmap, AD2S1210_REG_LOT_LOW_THRD, &low_reg_val); + if (ret < 0) + goto error_ret; + + hysteresis = high_reg_val - low_reg_val; + high_reg_val = val2 / ad2s1210_lot_threshold_urad_per_lsb[st->resolution]; + low_reg_val = high_reg_val - hysteresis; + + ret = regmap_write(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, high_reg_val); + if (ret < 0) + goto error_ret; + + ret = regmap_write(st->regmap, AD2S1210_REG_LOT_LOW_THRD, low_reg_val); + +error_ret: + mutex_unlock(&st->lock); + + return ret; +} + +static int ad2s1210_get_lot_low_threshold(struct ad2s1210_state *st, + int *val, int *val2) +{ + unsigned int high_reg_val, low_reg_val; + int ret; + + mutex_lock(&st->lock); + ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, &high_reg_val); + if (ret < 0) + goto error_ret; + + ret = regmap_read(st->regmap, AD2S1210_REG_LOT_LOW_THRD, &low_reg_val); + +error_ret: + mutex_unlock(&st->lock); + + if (ret < 0) + return ret; + + /* sysfs value is hysteresis rather than actual low value */ + *val = 0; + *val2 = (high_reg_val - low_reg_val) * + ad2s1210_lot_threshold_urad_per_lsb[st->resolution]; + return IIO_VAL_INT_PLUS_MICRO; +} + +static int ad2s1210_set_lot_low_threshold(struct ad2s1210_state *st, + int val, int val2) +{ + unsigned int reg_val, hysteresis; + int ret; + + /* all valid values are between 0 and pi/4 radians */ + if (val != 0) + return -EINVAL; + + hysteresis = val2 / ad2s1210_lot_threshold_urad_per_lsb[st->resolution]; + + mutex_lock(&st->lock); + ret = regmap_read(st->regmap, AD2S1210_REG_LOT_HIGH_THRD, ®_val); + if (ret < 0) + goto error_ret; + + ret = regmap_write(st->regmap, AD2S1210_REG_LOT_LOW_THRD, + reg_val - hysteresis); + +error_ret: + mutex_unlock(&st->lock); + + return ret; +} + static int ad2s1210_get_excitation_frequency(struct ad2s1210_state *st, int *val) { unsigned int reg_val; @@ -608,12 +725,19 @@ static IIO_DEVICE_ATTR(dos_rst_max_thrd, 0644, static IIO_DEVICE_ATTR(dos_rst_min_thrd, 0644, ad2s1210_show_reg, ad2s1210_store_reg, AD2S1210_REG_DOS_RST_MIN_THRD); -static IIO_DEVICE_ATTR(lot_high_thrd, 0644, - ad2s1210_show_reg, ad2s1210_store_reg, - AD2S1210_REG_LOT_HIGH_THRD); -static IIO_DEVICE_ATTR(lot_low_thrd, 0644, - ad2s1210_show_reg, ad2s1210_store_reg, - AD2S1210_REG_LOT_LOW_THRD); + +static const struct iio_event_spec ad2s1210_position_event_spec[] = { + { + /* Tracking error exceeds LOT threshold fault. */ + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_RISING, + .mask_separate = + /* Loss of tracking high threshold. */ + BIT(IIO_EV_INFO_VALUE) | + /* Loss of tracking low threshold. */ + BIT(IIO_EV_INFO_HYSTERESIS), + }, +}; static const struct iio_event_spec ad2s1210_phase_event_spec[] = { { @@ -658,6 +782,15 @@ static const struct iio_chan_spec ad2s1210_channels[] = { }, IIO_CHAN_SOFT_TIMESTAMP(2), { + /* used to configure LOT thresholds and get tracking error */ + .type = IIO_ANGL, + .indexed = 1, + .channel = 1, + .scan_index = -1, + .event_spec = ad2s1210_position_event_spec, + .num_event_specs = ARRAY_SIZE(ad2s1210_position_event_spec), + }, + { /* used to configure phase lock range and get phase lock error */ .type = IIO_PHASE, .indexed = 1, @@ -684,8 +817,6 @@ static struct attribute *ad2s1210_attributes[] = { &iio_dev_attr_dos_mis_thrd.dev_attr.attr, &iio_dev_attr_dos_rst_max_thrd.dev_attr.attr, &iio_dev_attr_dos_rst_min_thrd.dev_attr.attr, - &iio_dev_attr_lot_high_thrd.dev_attr.attr, - &iio_dev_attr_lot_low_thrd.dev_attr.attr, NULL, }; @@ -693,14 +824,40 @@ static const struct attribute_group ad2s1210_attribute_group = { .attrs = ad2s1210_attributes, }; +static ssize_t +in_angl1_thresh_rising_value_available_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev)); + int step = ad2s1210_lot_threshold_urad_per_lsb[st->resolution]; + + return sysfs_emit(buf, "[0 0.%06d 0.%06d]\n", step, step * 0x7F); +} + +static ssize_t +in_angl1_thresh_rising_hysteresis_available_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev)); + int step = ad2s1210_lot_threshold_urad_per_lsb[st->resolution]; + + return sysfs_emit(buf, "[0 0.%06d 0.%06d]\n", step, step * 0x7F); +} + static IIO_CONST_ATTR(in_phase0_mag_rising_value_available, __stringify(PHASE_44_DEG_TO_RAD_INT) "." __stringify(PHASE_44_DEG_TO_RAD_MICRO) " " __stringify(PHASE_360_DEG_TO_RAD_INT) "." __stringify(PHASE_360_DEG_TO_RAD_MICRO)); +static IIO_DEVICE_ATTR_RO(in_angl1_thresh_rising_value_available, 0); +static IIO_DEVICE_ATTR_RO(in_angl1_thresh_rising_hysteresis_available, 0); static struct attribute *ad2s1210_event_attributes[] = { &iio_const_attr_in_phase0_mag_rising_value_available.dev_attr.attr, + &iio_dev_attr_in_angl1_thresh_rising_value_available.dev_attr.attr, + &iio_dev_attr_in_angl1_thresh_rising_hysteresis_available.dev_attr.attr, NULL, }; @@ -742,6 +899,15 @@ static int ad2s1210_read_event_value(struct iio_dev *indio_dev, struct ad2s1210_state *st = iio_priv(indio_dev); switch (chan->type) { + case IIO_ANGL: + switch (info) { + case IIO_EV_INFO_VALUE: + return ad2s1210_get_lot_high_threshold(st, val, val2); + case IIO_EV_INFO_HYSTERESIS: + return ad2s1210_get_lot_low_threshold(st, val, val2); + default: + return -EINVAL; + } case IIO_PHASE: return ad2s1210_get_phase_lock_range(st, val, val2); default: @@ -759,6 +925,15 @@ static int ad2s1210_write_event_value(struct iio_dev *indio_dev, struct ad2s1210_state *st = iio_priv(indio_dev); switch (chan->type) { + case IIO_ANGL: + switch (info) { + case IIO_EV_INFO_VALUE: + return ad2s1210_set_lot_high_threshold(st, val, val2); + case IIO_EV_INFO_HYSTERESIS: + return ad2s1210_set_lot_low_threshold(st, val, val2); + default: + return -EINVAL; + } case IIO_PHASE: return ad2s1210_set_phase_lock_range(st, val, val2); default: |