From 7dde2719fb3892ad69da4b1c5790bac5ea958a09 Mon Sep 17 00:00:00 2001 From: David Lechner Date: Thu, 5 Oct 2023 19:50:20 -0500 Subject: staging: iio: resolver: ad2s1210: convert fexcit to channel attribute The ad2s1210 driver has a device-specific attribute `fexcit` for setting the frequency of the excitation output. This converts it to a channel in order to use standard IIO ABI. The excitation frequency is an analog output that generates a sine wave. Only the frequency is configurable. According to the datasheet, the specified range of the excitation frequency is from 2 kHz to 20 kHz and can be set in increments of 250 Hz. Signed-off-by: David Lechner Link: https://lore.kernel.org/r/20231005-ad2s1210-mainline-v4-3-ec00746840fc@baylibre.com Signed-off-by: Jonathan Cameron --- drivers/staging/iio/resolver/ad2s1210.c | 123 ++++++++++++++++++-------------- 1 file changed, 71 insertions(+), 52 deletions(-) (limited to 'drivers/staging/iio/resolver/ad2s1210.c') diff --git a/drivers/staging/iio/resolver/ad2s1210.c b/drivers/staging/iio/resolver/ad2s1210.c index af063eb25e9c..0c7772725330 100644 --- a/drivers/staging/iio/resolver/ad2s1210.c +++ b/drivers/staging/iio/resolver/ad2s1210.c @@ -227,54 +227,6 @@ static int ad2s1210_set_resolution_gpios(struct ad2s1210_state *st, bitmap); } -static ssize_t ad2s1210_show_fexcit(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev)); - unsigned int value; - u16 fexcit; - int ret; - - mutex_lock(&st->lock); - ret = regmap_read(st->regmap, AD2S1210_REG_EXCIT_FREQ, &value); - if (ret < 0) - goto error_ret; - - fexcit = value * st->clkin_hz / (1 << 15); - - ret = sprintf(buf, "%u\n", fexcit); - -error_ret: - mutex_unlock(&st->lock); - return ret; -} - -static ssize_t ad2s1210_store_fexcit(struct device *dev, - struct device_attribute *attr, - const char *buf, size_t len) -{ - struct ad2s1210_state *st = iio_priv(dev_to_iio_dev(dev)); - u16 fexcit; - int ret; - - ret = kstrtou16(buf, 10, &fexcit); - if (ret < 0 || fexcit < AD2S1210_MIN_EXCIT || fexcit > AD2S1210_MAX_EXCIT) - return -EINVAL; - - mutex_lock(&st->lock); - ret = ad2s1210_reinit_excitation_frequency(st, fexcit); - if (ret < 0) - goto error_ret; - - ret = len; - -error_ret: - mutex_unlock(&st->lock); - - return ret; -} - static ssize_t ad2s1210_show_resolution(struct device *dev, struct device_attribute *attr, char *buf) @@ -478,6 +430,38 @@ static int ad2s1210_set_hysteresis(struct ad2s1210_state *st, int val) return ret; } +static int ad2s1210_get_excitation_frequency(struct ad2s1210_state *st, int *val) +{ + unsigned int reg_val; + int ret; + + mutex_lock(&st->lock); + ret = regmap_read(st->regmap, AD2S1210_REG_EXCIT_FREQ, ®_val); + if (ret < 0) + goto error_ret; + + *val = reg_val * st->clkin_hz / (1 << 15); + ret = IIO_VAL_INT; + +error_ret: + mutex_unlock(&st->lock); + return ret; +} + +static int ad2s1210_set_excitation_frequency(struct ad2s1210_state *st, int val) +{ + int ret; + + if (val < AD2S1210_MIN_EXCIT || val > AD2S1210_MAX_EXCIT) + return -EINVAL; + + mutex_lock(&st->lock); + ret = ad2s1210_reinit_excitation_frequency(st, val); + mutex_unlock(&st->lock); + + return ret; +} + static const int ad2s1210_velocity_scale[] = { 17089132, /* 8.192MHz / (2*pi * 2500 / 2^15) */ 42722830, /* 8.192MHz / (2*pi * 1000 / 2^15) */ @@ -510,6 +494,13 @@ static int ad2s1210_read_raw(struct iio_dev *indio_dev, default: return -EINVAL; } + case IIO_CHAN_INFO_FREQUENCY: + switch (chan->type) { + case IIO_ALTVOLTAGE: + return ad2s1210_get_excitation_frequency(st, val); + default: + return -EINVAL; + } case IIO_CHAN_INFO_HYSTERESIS: switch (chan->type) { case IIO_ANGL: @@ -527,9 +518,24 @@ static int ad2s1210_read_avail(struct iio_dev *indio_dev, const int **vals, int *type, int *length, long mask) { + static const int excitation_frequency_available[] = { + AD2S1210_MIN_EXCIT, + 250, /* step */ + AD2S1210_MAX_EXCIT, + }; + struct ad2s1210_state *st = iio_priv(indio_dev); switch (mask) { + case IIO_CHAN_INFO_FREQUENCY: + switch (chan->type) { + case IIO_ALTVOLTAGE: + *type = IIO_VAL_INT; + *vals = excitation_frequency_available; + return IIO_AVAIL_RANGE; + default: + return -EINVAL; + } case IIO_CHAN_INFO_HYSTERESIS: switch (chan->type) { case IIO_ANGL: @@ -552,6 +558,13 @@ static int ad2s1210_write_raw(struct iio_dev *indio_dev, struct ad2s1210_state *st = iio_priv(indio_dev); switch (mask) { + case IIO_CHAN_INFO_FREQUENCY: + switch (chan->type) { + case IIO_ALTVOLTAGE: + return ad2s1210_set_excitation_frequency(st, val); + default: + return -EINVAL; + } case IIO_CHAN_INFO_HYSTERESIS: switch (chan->type) { case IIO_ANGL: @@ -564,8 +577,6 @@ static int ad2s1210_write_raw(struct iio_dev *indio_dev, } } -static IIO_DEVICE_ATTR(fexcit, 0644, - ad2s1210_show_fexcit, ad2s1210_store_fexcit, 0); static IIO_DEVICE_ATTR(bits, 0644, ad2s1210_show_resolution, ad2s1210_store_resolution, 0); static IIO_DEVICE_ATTR(fault, 0644, @@ -609,11 +620,19 @@ static const struct iio_chan_spec ad2s1210_channels[] = { .channel = 0, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), - } + }, { + /* excitation frequency output */ + .type = IIO_ALTVOLTAGE, + .indexed = 1, + .channel = 0, + .output = 1, + .scan_index = -1, + .info_mask_separate = BIT(IIO_CHAN_INFO_FREQUENCY), + .info_mask_separate_available = BIT(IIO_CHAN_INFO_FREQUENCY), + }, }; static struct attribute *ad2s1210_attributes[] = { - &iio_dev_attr_fexcit.dev_attr.attr, &iio_dev_attr_bits.dev_attr.attr, &iio_dev_attr_fault.dev_attr.attr, &iio_dev_attr_los_thrd.dev_attr.attr, -- cgit v1.2.3