Allow triggering both zero-scale and full-scale calibration via sysfs in
the same way as it's done for ad7173.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxx>
---
drivers/iio/adc/ad7124.c | 141 ++++++++++++++++++++++++++++++++++-----
1 file changed, 124 insertions(+), 17 deletions(-)
diff --git a/drivers/iio/adc/ad7124.c b/drivers/iio/adc/ad7124.c
index 5c2e5a518af3..ad14503e9797 100644
--- a/drivers/iio/adc/ad7124.c
+++ b/drivers/iio/adc/ad7124.c
@@ -4,6 +4,9 @@
*
* Copyright 2018 Analog Devices Inc.
*/
+
+#define DEBUG
+
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/clk.h>
@@ -181,6 +184,7 @@ struct ad7124_channel {
struct ad7124_channel_config cfg;
unsigned int ain;
unsigned int slot;
+ u8 syscalib_mode;
};
struct ad7124_state {
@@ -202,23 +206,6 @@ struct ad7124_state {
DECLARE_KFIFO(live_cfgs_fifo, struct ad7124_channel_config *, AD7124_MAX_CONFIGS);
};
-static const struct iio_chan_spec ad7124_channel_template = {
- .type = IIO_VOLTAGE,
- .indexed = 1,
- .differential = 1,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
- BIT(IIO_CHAN_INFO_SCALE) |
- BIT(IIO_CHAN_INFO_OFFSET) |
- BIT(IIO_CHAN_INFO_SAMP_FREQ) |
- BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
- .scan_type = {
- .sign = 'u',
- .realbits = 24,
- .storagebits = 32,
- .endianness = IIO_BE,
- },
-};
-
static struct ad7124_chip_info ad7124_chip_info_tbl[] = {
[ID_AD7124_4] = {
.name = "ad7124-4",
@@ -903,6 +890,126 @@ static int ad7124_check_chip_id(struct ad7124_state *st)
return 0;
}
+enum {
+ AD7124_SYSCALIB_ZERO_SCALE,
+ AD7124_SYSCALIB_FULL_SCALE,
+};
+
+static ssize_t ad7124_write_syscalib(struct iio_dev *indio_dev,
+ uintptr_t private,
+ const struct iio_chan_spec *chan,
+ const char *buf, size_t len)
+{
+ struct ad7124_state *st = iio_priv(indio_dev);
+ struct ad7124_channel *ch = &st->channels[chan->channel];
+ struct device *dev = &st->sd.spi->dev;
+ bool sys_calib;
+ int ret, mode;
+
+ ret = kstrtobool(buf, &sys_calib);
+ if (ret)
+ return ret;
+
+ mode = ch->syscalib_mode;
+ if (sys_calib) {
+ if (mode == AD7124_SYSCALIB_ZERO_SCALE) {
+ ch->cfg.calibration_offset = 0x800000;
+
+ ret = ad_sd_calibrate(&st->sd, AD7124_MODE_CAL_SYS_ZERO,
+ chan->address);
+ if (ret < 0)
+ return ret;
+
+ ret = ad_sd_read_reg(&st->sd, AD7124_OFFSET(ch->cfg.cfg_slot), 3,
+ &ch->cfg.calibration_offset);
+ if (ret < 0)
+ return ret;
+
+ dev_dbg(dev, "offset for channel %d after zero-scale calibration: 0x%x\n",
+ chan->channel, ch->cfg.calibration_offset);
+ } else {
+ ch->cfg.calibration_gain = st->gain_default;
+
+ ret = ad_sd_calibrate(&st->sd, AD7124_MODE_CAL_SYS_FULL,
+ chan->address);
+ if (ret < 0)
+ return ret;
+
+ ret = ad_sd_read_reg(&st->sd, AD7124_GAIN(ch->cfg.cfg_slot), 3,
+ &ch->cfg.calibration_gain);
+ if (ret < 0)
+ return ret;
+
+ dev_dbg(dev, "gain for channel %d after full-scale calibration: 0x%x\n",
+ chan->channel, ch->cfg.calibration_gain);
+ }
+ }
+
+ return len;
+}
+
+static const char * const ad7124_syscalib_modes[] = {
+ [AD7124_SYSCALIB_ZERO_SCALE] = "zero_scale",
+ [AD7124_SYSCALIB_FULL_SCALE] = "full_scale",
+};
+
+static int ad7124_set_syscalib_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ unsigned int mode)
+{
+ struct ad7124_state *st = iio_priv(indio_dev);
+
+ st->channels[chan->channel].syscalib_mode = mode;
+
+ return 0;
+}
+
+static int ad7124_get_syscalib_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct ad7124_state *st = iio_priv(indio_dev);
+
+ return st->channels[chan->channel].syscalib_mode;
+}
+
+static const struct iio_enum ad7124_syscalib_mode_enum = {
+ .items = ad7124_syscalib_modes,
+ .num_items = ARRAY_SIZE(ad7124_syscalib_modes),
+ .set = ad7124_set_syscalib_mode,
+ .get = ad7124_get_syscalib_mode
+};
+
+static const struct iio_chan_spec_ext_info ad7124_calibsys_ext_info[] = {
+ {
+ .name = "sys_calibration",
+ .write = ad7124_write_syscalib,
+ .shared = IIO_SEPARATE,
+ },
+ IIO_ENUM("sys_calibration_mode", IIO_SEPARATE,
+ &ad7124_syscalib_mode_enum),
+ IIO_ENUM_AVAILABLE("sys_calibration_mode", IIO_SHARED_BY_TYPE,
+ &ad7124_syscalib_mode_enum),
+ { }
+};
+
+static const struct iio_chan_spec ad7124_channel_template = {
+ .type = IIO_VOLTAGE,
+ .indexed = 1,
+ .differential = 1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET) |
+ BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+ BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 24,
+ .storagebits = 32,
+ .endianness = IIO_BE,
+ },
+ .ext_info = ad7124_calibsys_ext_info,
+};
+
/*
* Input specifiers 8 - 15 are explicitly reserved for ad7124-4
* while they are fine for ad7124-8. Values above 31 don't fit
--
2.47.1
