Merge tag 'iio-for-5.13a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

1st set of IIO/counter device support, features and cleanup in the 5.13 cycle

Big set in here from Alexandru Ardelean enabling multiple buffer support.
This includes providing a new directory per buffer that combines
what was previously in buffer/ and scan_elements/. Old interfaces still
in place for compatiblity.

Note immuatable branch for scmi patches to allow for some significant
rework going on in that subsystem.  Merge required updating to reflect
some changes in IIO.

Late rebase to fix some wrong fixes tags due to some earlier rebases
made necessary by messing up the immutable branch.

IIO New Device Support
* adi,ad5686
  - Add info to support AD5673R and AD5677R
* bosch,bmi088
  - New driver supporting this accelerometer + gyroscope
* cros_ec_mkbp
  - New driver for this proximity sensor that exposes a 'front'
    sensor. Very simple switch like device, but driver allows it
    to share interface with more sophisticated proximity sensors.
* iio_scmi
  - New driver to support ARM SCMI protocol to expose underlying
    accelerometers and gyroscopes via this firmware interface.
* st,st_magn
  - Add ID for IISMDC magnetometer.
* ti,ads131e0
  - New driver supporting ads131e04, ads131e06 and ads131e08 24 bit ADCs

Counter New Device Support
* IRQ or GPIO based counter
  - New driver for a conceptually simple counter that uses interrupts
    to perform the count.

Features
* core
  - Dual buffer supprt including:
     Various helpers to centralize handling of bufferer related elements.
     Document existing and new IOCTLs
     Register the IIO chrdev only if it can actually be used for anything.
     Rework attribute group creation in the core (lots of patches)
     Merge buffer/ and scan_elements/ entries into one list + maintain
     backwards compatible set.
     Introduce the internal logic and IOCTL to allow multiple buffers
     + access to an anon FD per buffer to actually read from it.
     Tidy up tools/iio/iio_generic_buffer and switch to new interfaces.
     Update ABI docs.
     A few follow up fixes, unsuprising as this was a huge bit of rework.
  - Move common case setting of trig->parent to the core.
  - Provide an iio_read_channel_processed_scale() to avoid loss of
    precision from iio_read_channel_processed() then applying integer
    scale. Use it in ntc_thermistor driver in hwmon.
  - Allow drivers to specify labels from elsewhere than DT. Use it for
    bmc150 and kxcjk-1013 labels related to position on 2 in one tablets.
  - Document label usage for proximity and accelerometer sensors.
  - Some local variable renames for consistency
tools
  - Add -a parameter to iio_event_monitor to allow autoenabling of events.
* acpi_als
  - Add trigger support for devices that don't support notification method.
* adi,ad7124
  - Allow more than 8 channels.  This is a complex little device, but is
    capable of supporting up to 16 channels if the share certain
    configuration settings.
* hrtimer-trigger
  - Support sampling frequency below 1Hz.
* mediatek,mt8195-auxadc
  - Add compatible to binding docs (always also includes mt8173)
* st,stm32-adc
  - Enable timetamps when not using DMA.
* vishay,vcnl3020
  - Sampling frequency control.

Cleanup and minor fixes:
* treewide
  - Use some getter and setter functions instead of opencoding.
  - Set of fixes for pointless casts in various drivers.
  - Avoid wrong kernel-doc marking on comment blocks.
  - Fix various other minor kernel-doc issues shown by W=1
* core
  - Use a signed temporary for IIO_VAL_FRACTIONAL_LOG2 to avoid odd casts.
  - Fix IIO_VAL_FRACTIONAL_LOG2 for values between -1.0 and 0.0
  - Add unit tests for iio_format_value()
* docs
  - Fix formatting/typos in iio_configfs.rst and buffers.rst
  - Add documentation of index in buffers.rst
  - Fix scan element description
  - Avoid some issues with HTML generation from ABI docs by moving
    duplicated defintions to more generic files.
  - Drop reference to long dead mailing list.
* 104-quad
  - Remove left over deprecated IIO counter ABI.
* adi,adi-axi-adc
  - Fix wrong bit of docs.
* adi,ad5791
  - Typos
* adi,ad9834
   - Switch to device managed functions in probe.
* adi,adis*
  - Add and use helpers for locking to reduced duplication.
* adi,adis16480
  - Fix calculation of sampling frequency when using pulse per second input.
* adi,adis16475
  - Calculate the IMU scaled internal sampling rate and runtime depending
    on sysfs based configuration rather than getting from DT. Drop now
    unnecessary property from DT bindings doc.
* cros_ec
   - Fix result of a series of recent changes that means extended buffer
     attributes turn up in the wrong place. Too complex to revert the
     various patches unfortunately so this is a bit messy.
* fsl,mma3452
  - Indentation cleanup.
* hid-sensors
  - Size of storage needs to increase for some parts when using quaternions.
  - Move the get sensistivity attribute to hid-sensors-common to reduce
    duplication.  Enable it for more device types.
  - Correctly handle relative sensitivity if reported that way including
    documenting the new ABI.
* maxim,max517
  - Use device managed functions in probe.
* mediatek,mt6360-adc
  - Use asm/unaligned.h instead of directly including
    unaligned/be_byteshift.h
* novuton,npcm-adc
  - Local lock instead of missusing mlock.
* semtech,sx9500
  - Typos
* st,sensor
  - typo fix
* st,spear-adc
  - Local lock instead of missusing mlock.
* st,stm32-adc
  - Long standing HAS_IOMEM dependency fix.
* st,stm32-counter
  - Remove left over deprecated IIO counter ABI.
* ti,palmas-adc
  - Local lock instead of missusing mlock.
* ti,tmp007
  - Switch to device managed functions in probe.

Other
* MAINTAINERS
  - Move Peter Meerwald-Stadler to Credits at his request

* tag 'iio-for-5.13a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (119 commits)
  iio: acpi_als: Add trigger support
  iio: acpi_als: Add local variable dev in probe
  iio: acpi_als: Add timestamp channel
  iio: adc: ad7292: Modify the bool initialization assignment
  iio: cros: unify hw fifo attributes without API changes
  iio: kfifo: add devm_iio_triggered_buffer_setup_ext variant
  iio: event_monitor: Enable events before monitoring
  dt-bindings: iio: adc: Add compatible for Mediatek MT8195
  iio:magnetometer: Add Support for ST IIS2MDC
  dt-bindings: iio: st,st-sensors add IIS2MDC.
  staging: iio: ad9832: kernel-doc fixes
  iio:dac:max517.c: Use devm_iio_device_register()
  iio:cros_ec_sensors: Fix a wrong function name in kernel doc.
  iio: buffer: kfifo_buf: kernel-doc, typo in function name.
  iio: accel: sca3000: kernel-doc fixes. Missing - and wrong function names.
  iio: adc: adi-axi-adc: Drop false marking for kernel-doc
  iio: adc: cpcap-adc: kernel-doc fix - that should be _ in structure name
  iio: dac: ad5504: fix wrong part number in kernel-doc structure name.
  iio: dac: ad5770r: kernel-doc fix case of letter R wrong in structure name
  iio: adc: ti-adc084s021: kernel-doc fixes, missing function names
  ...

13 files changed, 221 insertions, 120 deletions

diff --git a/drivers/iio/imu/adis16400.c b/drivers/iio/imu/adis16400.c
index 785a4ce606d8..768aa493a1a6 100644
--- a/drivers/iio/imu/adis16400.c
+++ b/drivers/iio/imu/adis16400.c
@@ -504,7 +504,6 @@ static int adis16400_write_raw(struct iio_dev *indio_dev,
 	struct iio_chan_spec const *chan, int val, int val2, long info)
 {
 	struct adis16400_state *st = iio_priv(indio_dev);
-	struct mutex *slock = &st->adis.state_lock;
 	int ret, sps;
 
 	switch (info) {
@@ -517,18 +516,18 @@ static int adis16400_write_raw(struct iio_dev *indio_dev,
 		 * Need to cache values so we can update if the frequency
 		 * changes.
 		 */
-		mutex_lock(slock);
+		adis_dev_lock(&st->adis);
 		st->filt_int = val;
 		/* Work out update to current value */
 		sps = st->variant->get_freq(st);
 		if (sps < 0) {
-			mutex_unlock(slock);
+			adis_dev_unlock(&st->adis);
 			return sps;
 		}
 
 		ret = __adis16400_set_filter(indio_dev, sps,
 			val * 1000 + val2 / 1000);
-		mutex_unlock(slock);
+		adis_dev_unlock(&st->adis);
 		return ret;
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		sps = val * 1000 + val2 / 1000;
@@ -536,9 +535,9 @@ static int adis16400_write_raw(struct iio_dev *indio_dev,
 		if (sps <= 0)
 			return -EINVAL;
 
-		mutex_lock(slock);
+		adis_dev_lock(&st->adis);
 		ret = st->variant->set_freq(st, sps);
-		mutex_unlock(slock);
+		adis_dev_unlock(&st->adis);
 		return ret;
 	default:
 		return -EINVAL;
@@ -549,7 +548,6 @@ static int adis16400_read_raw(struct iio_dev *indio_dev,
 	struct iio_chan_spec const *chan, int *val, int *val2, long info)
 {
 	struct adis16400_state *st = iio_priv(indio_dev);
-	struct mutex *slock = &st->adis.state_lock;
 	int16_t val16;
 	int ret;
 
@@ -605,17 +603,17 @@ static int adis16400_read_raw(struct iio_dev *indio_dev,
 		*val = st->variant->temp_offset;
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
-		mutex_lock(slock);
+		adis_dev_lock(&st->adis);
 		/* Need both the number of taps and the sampling frequency */
 		ret = __adis_read_reg_16(&st->adis,
 						ADIS16400_SENS_AVG,
 						&val16);
 		if (ret) {
-			mutex_unlock(slock);
+			adis_dev_unlock(&st->adis);
 			return ret;
 		}
 		ret = st->variant->get_freq(st);
-		mutex_unlock(slock);
+		adis_dev_unlock(&st->adis);
 		if (ret)
 			return ret;
 		ret /= adis16400_3db_divisors[val16 & 0x07];
@@ -623,9 +621,9 @@ static int adis16400_read_raw(struct iio_dev *indio_dev,
 		*val2 = (ret % 1000) * 1000;
 		return IIO_VAL_INT_PLUS_MICRO;
 	case IIO_CHAN_INFO_SAMP_FREQ:
-		mutex_lock(slock);
+		adis_dev_lock(&st->adis);
 		ret = st->variant->get_freq(st);
-		mutex_unlock(slock);
+		adis_dev_unlock(&st->adis);
 		if (ret)
 			return ret;
 		*val = ret / 1000;
diff --git a/drivers/iio/imu/adis16475.c b/drivers/iio/imu/adis16475.c
index 197d48240991..8f6bea4b6608 100644
--- a/drivers/iio/imu/adis16475.c
+++ b/drivers/iio/imu/adis16475.c
@@ -17,6 +17,8 @@
 #include <linux/iio/sysfs.h>
 #include <linux/iio/trigger_consumer.h>
 #include <linux/irq.h>
+#include <linux/lcm.h>
+#include <linux/math.h>
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
 #include <linux/property.h>
@@ -101,6 +103,7 @@ struct adis16475 {
 	u32 clk_freq;
 	bool burst32;
 	unsigned long lsb_flag;
+	u16 sync_mode;
 	/* Alignment needed for the timestamp */
 	__be16 data[ADIS16475_MAX_SCAN_DATA] __aligned(8);
 };
@@ -117,6 +120,11 @@ enum {
 	ADIS16475_SCAN_CRC_FAILURE,
 };
 
+static bool low_rate_allow;
+module_param(low_rate_allow, bool, 0444);
+MODULE_PARM_DESC(low_rate_allow,
+		 "Allow IMU rates below the minimum advisable when external clk is used in SCALED mode (default: N)");
+
 #ifdef CONFIG_DEBUG_FS
 static ssize_t adis16475_show_firmware_revision(struct file *file,
 						char __user *userbuf,
@@ -253,25 +261,92 @@ static int adis16475_get_freq(struct adis16475 *st, u32 *freq)
 {
 	int ret;
 	u16 dec;
+	u32 sample_rate = st->clk_freq;
+
+	adis_dev_lock(&st->adis);
+
+	if (st->sync_mode == ADIS16475_SYNC_SCALED) {
+		u16 sync_scale;
+
+		ret = __adis_read_reg_16(&st->adis, ADIS16475_REG_UP_SCALE, &sync_scale);
+		if (ret)
+			goto error;
+
+		sample_rate = st->clk_freq * sync_scale;
+	}
 
-	ret = adis_read_reg_16(&st->adis, ADIS16475_REG_DEC_RATE, &dec);
+	ret = __adis_read_reg_16(&st->adis, ADIS16475_REG_DEC_RATE, &dec);
 	if (ret)
-		return -EINVAL;
+		goto error;
 
-	*freq = DIV_ROUND_CLOSEST(st->clk_freq, dec + 1);
+	adis_dev_unlock(&st->adis);
+
+	*freq = DIV_ROUND_CLOSEST(sample_rate, dec + 1);
 
 	return 0;
+error:
+	adis_dev_unlock(&st->adis);
+	return ret;
 }
 
 static int adis16475_set_freq(struct adis16475 *st, const u32 freq)
 {
 	u16 dec;
 	int ret;
+	u32 sample_rate = st->clk_freq;
 
 	if (!freq)
 		return -EINVAL;
 
-	dec = DIV_ROUND_CLOSEST(st->clk_freq, freq);
+	adis_dev_lock(&st->adis);
+	/*
+	 * When using sync scaled mode, the input clock needs to be scaled so that we have
+	 * an IMU sample rate between (optimally) 1900 and 2100. After this, we can use the
+	 * decimation filter to lower the sampling rate in order to get what the user wants.
+	 * Optimally, the user sample rate is a multiple of both the IMU sample rate and
+	 * the input clock. Hence, calculating the sync_scale dynamically gives us better
+	 * chances of achieving a perfect/integer value for DEC_RATE. The math here is:
+	 *	1. lcm of the input clock and the desired output rate.
+	 *	2. get the highest multiple of the previous result lower than the adis max rate.
+	 *	3. The last result becomes the IMU sample rate. Use that to calculate SYNC_SCALE
+	 *	   and DEC_RATE (to get the user output rate)
+	 */
+	if (st->sync_mode == ADIS16475_SYNC_SCALED) {
+		unsigned long scaled_rate = lcm(st->clk_freq, freq);
+		int sync_scale;
+
+		/*
+		 * If lcm is bigger than the IMU maximum sampling rate there's no perfect
+		 * solution. In this case, we get the highest multiple of the input clock
+		 * lower than the IMU max sample rate.
+		 */
+		if (scaled_rate > 2100000)
+			scaled_rate = 2100000 / st->clk_freq * st->clk_freq;
+		else
+			scaled_rate = 2100000 / scaled_rate * scaled_rate;
+
+		/*
+		 * This is not an hard requirement but it's not advised to run the IMU
+		 * with a sample rate lower than 4000Hz due to possible undersampling
+		 * issues. However, there are users that might really want to take the risk.
+		 * Hence, we provide a module parameter for them. If set, we allow sample
+		 * rates lower than 4KHz. By default, we won't allow this and we just roundup
+		 * the rate to the next multiple of the input clock bigger than 4KHz. This
+		 * is done like this as in some cases (when DEC_RATE is 0) might give
+		 * us the closest value to the one desired by the user...
+		 */
+		if (scaled_rate < 1900000 && !low_rate_allow)
+			scaled_rate = roundup(1900000, st->clk_freq);
+
+		sync_scale = scaled_rate / st->clk_freq;
+		ret = __adis_write_reg_16(&st->adis, ADIS16475_REG_UP_SCALE, sync_scale);
+		if (ret)
+			goto error;
+
+		sample_rate = scaled_rate;
+	}
+
+	dec = DIV_ROUND_CLOSEST(sample_rate, freq);
 
 	if (dec)
 		dec--;
@@ -281,7 +356,7 @@ static int adis16475_set_freq(struct adis16475 *st, const u32 freq)
 
 	ret = adis_write_reg_16(&st->adis, ADIS16475_REG_DEC_RATE, dec);
 	if (ret)
-		return ret;
+		goto error;
 
 	/*
 	 * If decimation is used, then gyro and accel data will have meaningful
@@ -290,6 +365,9 @@ static int adis16475_set_freq(struct adis16475 *st, const u32 freq)
 	assign_bit(ADIS16475_LSB_DEC_MASK, &st->lsb_flag, dec);
 
 	return 0;
+error:
+	adis_dev_unlock(&st->adis);
+	return ret;
 }
 
 /* The values are approximated. */
@@ -1085,6 +1163,7 @@ static int adis16475_config_sync_mode(struct adis16475 *st)
 	}
 
 	sync = &st->info->sync[sync_mode];
+	st->sync_mode = sync->sync_mode;
 
 	/* All the other modes require external input signal */
 	if (sync->sync_mode != ADIS16475_SYNC_OUTPUT) {
@@ -1112,37 +1191,20 @@ static int adis16475_config_sync_mode(struct adis16475 *st)
 
 		if (sync->sync_mode == ADIS16475_SYNC_SCALED) {
 			u16 up_scale;
-			u32 scaled_out_freq = 0;
+
 			/*
-			 * If we are in scaled mode, we must have an up_scale.
-			 * In scaled mode the allowable input clock range is
-			 * 1 Hz to 128 Hz, and the allowable output range is
-			 * 1900 to 2100 Hz. Hence, a scale must be given to
-			 * get the allowable output.
+			 * In sync scaled mode, the IMU sample rate is the clk_freq * sync_scale.
+			 * Hence, default the IMU sample rate to the highest multiple of the input
+			 * clock lower than the IMU max sample rate. The optimal range is
+			 * 1900-2100 sps...
 			 */
-			ret = device_property_read_u32(dev,
-						       "adi,scaled-output-hz",
-						       &scaled_out_freq);
-			if (ret) {
-				dev_err(dev, "adi,scaled-output-hz must be given when in scaled sync mode");
-				return -EINVAL;
-			} else if (scaled_out_freq < 1900 ||
-				   scaled_out_freq > 2100) {
-				dev_err(dev, "Invalid value: %u for adi,scaled-output-hz",
-					scaled_out_freq);
-				return -EINVAL;
-			}
-
-			up_scale = DIV_ROUND_CLOSEST(scaled_out_freq,
-						     st->clk_freq);
+			up_scale = 2100 / st->clk_freq;
 
 			ret = __adis_write_reg_16(&st->adis,
 						  ADIS16475_REG_UP_SCALE,
 						  up_scale);
 			if (ret)
 				return ret;
-
-			st->clk_freq = scaled_out_freq;
 		}
 
 		st->clk_freq *= 1000;
diff --git a/drivers/iio/imu/adis16480.c b/drivers/iio/imu/adis16480.c
index dfe86c589325..f81b86690b76 100644
--- a/drivers/iio/imu/adis16480.c
+++ b/drivers/iio/imu/adis16480.c
@@ -10,6 +10,7 @@
 #include <linux/of_irq.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
+#include <linux/math.h>
 #include <linux/mutex.h>
 #include <linux/device.h>
 #include <linux/kernel.h>
@@ -17,6 +18,7 @@
 #include <linux/slab.h>
 #include <linux/sysfs.h>
 #include <linux/module.h>
+#include <linux/lcm.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
@@ -170,6 +172,11 @@ static const char * const adis16480_int_pin_names[4] = {
 	[ADIS16480_PIN_DIO4] = "DIO4",
 };
 
+static bool low_rate_allow;
+module_param(low_rate_allow, bool, 0444);
+MODULE_PARM_DESC(low_rate_allow,
+		 "Allow IMU rates below the minimum advisable when external clk is used in PPS mode (default: N)");
+
 #ifdef CONFIG_DEBUG_FS
 
 static ssize_t adis16480_show_firmware_revision(struct file *file,
@@ -312,7 +319,8 @@ static int adis16480_debugfs_init(struct iio_dev *indio_dev)
 static int adis16480_set_freq(struct iio_dev *indio_dev, int val, int val2)
 {
 	struct adis16480 *st = iio_priv(indio_dev);
-	unsigned int t, reg;
+	unsigned int t, sample_rate = st->clk_freq;
+	int ret;
 
 	if (val < 0 || val2 < 0)
 		return -EINVAL;
@@ -321,28 +329,65 @@ static int adis16480_set_freq(struct iio_dev *indio_dev, int val, int val2)
 	if (t == 0)
 		return -EINVAL;
 
+	adis_dev_lock(&st->adis);
 	/*
-	 * When using PPS mode, the rate of data collection is equal to the
-	 * product of the external clock frequency and the scale factor in the
-	 * SYNC_SCALE register.
-	 * When using sync mode, or internal clock, the output data rate is
-	 * equal with  the clock frequency divided by DEC_RATE + 1.
+	 * When using PPS mode, the input clock needs to be scaled so that we have an IMU
+	 * sample rate between (optimally) 4000 and 4250. After this, we can use the
+	 * decimation filter to lower the sampling rate in order to get what the user wants.
+	 * Optimally, the user sample rate is a multiple of both the IMU sample rate and
+	 * the input clock. Hence, calculating the sync_scale dynamically gives us better
+	 * chances of achieving a perfect/integer value for DEC_RATE. The math here is:
+	 *	1. lcm of the input clock and the desired output rate.
+	 *	2. get the highest multiple of the previous result lower than the adis max rate.
+	 *	3. The last result becomes the IMU sample rate. Use that to calculate SYNC_SCALE
+	 *	   and DEC_RATE (to get the user output rate)
 	 */
 	if (st->clk_mode == ADIS16480_CLK_PPS) {
-		t = t / st->clk_freq;
-		reg = ADIS16495_REG_SYNC_SCALE;
-	} else {
-		t = st->clk_freq / t;
-		reg = ADIS16480_REG_DEC_RATE;
+		unsigned long scaled_rate = lcm(st->clk_freq, t);
+		int sync_scale;
+
+		/*
+		 * If lcm is bigger than the IMU maximum sampling rate there's no perfect
+		 * solution. In this case, we get the highest multiple of the input clock
+		 * lower than the IMU max sample rate.
+		 */
+		if (scaled_rate > st->chip_info->int_clk)
+			scaled_rate = st->chip_info->int_clk / st->clk_freq * st->clk_freq;
+		else
+			scaled_rate = st->chip_info->int_clk / scaled_rate * scaled_rate;
+
+		/*
+		 * This is not an hard requirement but it's not advised to run the IMU
+		 * with a sample rate lower than 4000Hz due to possible undersampling
+		 * issues. However, there are users that might really want to take the risk.
+		 * Hence, we provide a module parameter for them. If set, we allow sample
+		 * rates lower than 4KHz. By default, we won't allow this and we just roundup
+		 * the rate to the next multiple of the input clock bigger than 4KHz. This
+		 * is done like this as in some cases (when DEC_RATE is 0) might give
+		 * us the closest value to the one desired by the user...
+		 */
+		if (scaled_rate < 4000000 && !low_rate_allow)
+			scaled_rate = roundup(4000000, st->clk_freq);
+
+		sync_scale = scaled_rate / st->clk_freq;
+		ret = __adis_write_reg_16(&st->adis, ADIS16495_REG_SYNC_SCALE, sync_scale);
+		if (ret)
+			goto error;
+
+		sample_rate = scaled_rate;
 	}
 
+	t = DIV_ROUND_CLOSEST(sample_rate, t);
+	if (t)
+		t--;
+
 	if (t > st->chip_info->max_dec_rate)
 		t = st->chip_info->max_dec_rate;
 
-	if ((t != 0) && (st->clk_mode != ADIS16480_CLK_PPS))
-		t--;
-
-	return adis_write_reg_16(&st->adis, reg, t);
+	ret = __adis_write_reg_16(&st->adis, ADIS16480_REG_DEC_RATE, t);
+error:
+	adis_dev_unlock(&st->adis);
+	return ret;
 }
 
 static int adis16480_get_freq(struct iio_dev *indio_dev, int *val, int *val2)
@@ -350,34 +395,35 @@ static int adis16480_get_freq(struct iio_dev *indio_dev, int *val, int *val2)
 	struct adis16480 *st = iio_priv(indio_dev);
 	uint16_t t;
 	int ret;
-	unsigned int freq;
-	unsigned int reg;
+	unsigned int freq, sample_rate = st->clk_freq;
 
-	if (st->clk_mode == ADIS16480_CLK_PPS)
-		reg = ADIS16495_REG_SYNC_SCALE;
-	else
-		reg = ADIS16480_REG_DEC_RATE;
+	adis_dev_lock(&st->adis);
+
+	if (st->clk_mode == ADIS16480_CLK_PPS) {
+		u16 sync_scale;
+
+		ret = __adis_read_reg_16(&st->adis, ADIS16495_REG_SYNC_SCALE, &sync_scale);
+		if (ret)
+			goto error;
 
-	ret = adis_read_reg_16(&st->adis, reg, &t);
+		sample_rate = st->clk_freq * sync_scale;
+	}
+
+	ret = __adis_read_reg_16(&st->adis, ADIS16480_REG_DEC_RATE, &t);
 	if (ret)
-		return ret;
+		goto error;
 
-	/*
-	 * When using PPS mode, the rate of data collection is equal to the
-	 * product of the external clock frequency and the scale factor in the
-	 * SYNC_SCALE register.
-	 * When using sync mode, or internal clock, the output data rate is
-	 * equal with  the clock frequency divided by DEC_RATE + 1.
-	 */
-	if (st->clk_mode == ADIS16480_CLK_PPS)
-		freq = st->clk_freq * t;
-	else
-		freq = st->clk_freq / (t + 1);
+	adis_dev_unlock(&st->adis);
+
+	freq = DIV_ROUND_CLOSEST(sample_rate, (t + 1));
 
 	*val = freq / 1000;
 	*val2 = (freq % 1000) * 1000;
 
 	return IIO_VAL_INT_PLUS_MICRO;
+error:
+	adis_dev_unlock(&st->adis);
+	return ret;
 }
 
 enum {
@@ -552,7 +598,6 @@ static int adis16480_set_filter_freq(struct iio_dev *indio_dev,
 	const struct iio_chan_spec *chan, unsigned int freq)
 {
 	struct adis16480 *st = iio_priv(indio_dev);
-	struct mutex *slock = &st->adis.state_lock;
 	unsigned int enable_mask, offset, reg;
 	unsigned int diff, best_diff;
 	unsigned int i, best_freq;
@@ -563,7 +608,7 @@ static int adis16480_set_filter_freq(struct iio_dev *indio_dev,
 	offset = ad16480_filter_data[chan->scan_index][1];
 	enable_mask = BIT(offset + 2);
 
-	mutex_lock(slock);
+	adis_dev_lock(&st->adis);
 
 	ret = __adis_read_reg_16(&st->adis, reg, &val);
 	if (ret)
@@ -591,7 +636,7 @@ static int adis16480_set_filter_freq(struct iio_dev *indio_dev,
 
 	ret = __adis_write_reg_16(&st->adis, reg, val);
 out_unlock:
-	mutex_unlock(slock);
+	adis_dev_unlock(&st->adis);
 
 	return ret;
 }
@@ -1278,6 +1323,20 @@ static int adis16480_probe(struct spi_device *spi)
 
 		st->clk_freq = clk_get_rate(st->ext_clk);
 		st->clk_freq *= 1000; /* micro */
+		if (st->clk_mode == ADIS16480_CLK_PPS) {
+			u16 sync_scale;
+
+			/*
+			 * In PPS mode, the IMU sample rate is the clk_freq * sync_scale. Hence,
+			 * default the IMU sample rate to the highest multiple of the input clock
+			 * lower than the IMU max sample rate. The internal sample rate is the
+			 * max...
+			 */
+			sync_scale = st->chip_info->int_clk / st->clk_freq;
+			ret = __adis_write_reg_16(&st->adis, ADIS16495_REG_SYNC_SCALE, sync_scale);
+			if (ret)
+				return ret;
+		}
 	} else {
 		st->clk_freq = st->chip_info->int_clk;
 	}
diff --git a/drivers/iio/imu/adis_trigger.c b/drivers/iio/imu/adis_trigger.c
index 64e0ba51cb18..0f29e56200af 100644
--- a/drivers/iio/imu/adis_trigger.c
+++ b/drivers/iio/imu/adis_trigger.c
@@ -27,13 +27,6 @@ static const struct iio_trigger_ops adis_trigger_ops = {
 	.set_trigger_state = &adis_data_rdy_trigger_set_state,
 };
 
-static void adis_trigger_setup(struct adis *adis)
-{
-	adis->trig->dev.parent = &adis->spi->dev;
-	adis->trig->ops = &adis_trigger_ops;
-	iio_trigger_set_drvdata(adis->trig, adis);
-}
-
 static int adis_validate_irq_flag(struct adis *adis)
 {
 	/*
@@ -72,7 +65,8 @@ int devm_adis_probe_trigger(struct adis *adis, struct iio_dev *indio_dev)
 	if (!adis->trig)
 		return -ENOMEM;
 
-	adis_trigger_setup(adis);
+	adis->trig->ops = &adis_trigger_ops;
+	iio_trigger_set_drvdata(adis->trig, adis);
 
 	ret = adis_validate_irq_flag(adis);
 	if (ret)
diff --git a/drivers/iio/imu/fxos8700_i2c.c b/drivers/iio/imu/fxos8700_i2c.c
index 3ceb76366313..40a570325b0a 100644
--- a/drivers/iio/imu/fxos8700_i2c.c
+++ b/drivers/iio/imu/fxos8700_i2c.c
@@ -26,8 +26,7 @@ static int fxos8700_i2c_probe(struct i2c_client *client,
 
 	regmap = devm_regmap_init_i2c(client, &fxos8700_regmap_config);
 	if (IS_ERR(regmap)) {
-		dev_err(&client->dev, "Failed to register i2c regmap %d\n",
-			(int)PTR_ERR(regmap));
+		dev_err(&client->dev, "Failed to register i2c regmap %ld\n", PTR_ERR(regmap));
 		return PTR_ERR(regmap);
 	}
 
diff --git a/drivers/iio/imu/fxos8700_spi.c b/drivers/iio/imu/fxos8700_spi.c
index 57e7bb6444e7..27e694cce173 100644
--- a/drivers/iio/imu/fxos8700_spi.c
+++ b/drivers/iio/imu/fxos8700_spi.c
@@ -17,8 +17,7 @@ static int fxos8700_spi_probe(struct spi_device *spi)
 
 	regmap = devm_regmap_init_spi(spi, &fxos8700_regmap_config);
 	if (IS_ERR(regmap)) {
-		dev_err(&spi->dev, "Failed to register spi regmap %d\n",
-			(int)PTR_ERR(regmap));
+		dev_err(&spi->dev, "Failed to register spi regmap %ld\n", PTR_ERR(regmap));
 		return PTR_ERR(regmap);
 	}
 
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
index 3441b0d61c5d..383cc3250342 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
@@ -709,7 +709,6 @@ struct iio_dev *inv_icm42600_accel_init(struct inv_icm42600_state *st)
 	const char *name;
 	struct inv_icm42600_timestamp *ts;
 	struct iio_dev *indio_dev;
-	struct iio_buffer *buffer;
 	int ret;
 
 	name = devm_kasprintf(dev, GFP_KERNEL, "%s-accel", st->name);
@@ -720,23 +719,22 @@ struct iio_dev *inv_icm42600_accel_init(struct inv_icm42600_state *st)
 	if (!indio_dev)
 		return ERR_PTR(-ENOMEM);
 
-	buffer = devm_iio_kfifo_allocate(dev);
-	if (!buffer)
-		return ERR_PTR(-ENOMEM);
-
 	ts = iio_priv(indio_dev);
 	inv_icm42600_timestamp_init(ts, inv_icm42600_odr_to_period(st->conf.accel.odr));
 
 	iio_device_set_drvdata(indio_dev, st);
 	indio_dev->name = name;
 	indio_dev->info = &inv_icm42600_accel_info;
-	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
+	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->channels = inv_icm42600_accel_channels;
 	indio_dev->num_channels = ARRAY_SIZE(inv_icm42600_accel_channels);
 	indio_dev->available_scan_masks = inv_icm42600_accel_scan_masks;
-	indio_dev->setup_ops = &inv_icm42600_buffer_ops;
 
-	iio_device_attach_buffer(indio_dev, buffer);
+	ret = devm_iio_kfifo_buffer_setup(dev, indio_dev,
+					  INDIO_BUFFER_SOFTWARE,
+					  &inv_icm42600_buffer_ops);
+	if (ret)
+		return ERR_PTR(ret);
 
 	ret = devm_iio_device_register(dev, indio_dev);
 	if (ret)
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_gyro.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_gyro.c
index aee7b9ff4bf4..cec1dd0e0464 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_gyro.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_gyro.c
@@ -720,7 +720,6 @@ struct iio_dev *inv_icm42600_gyro_init(struct inv_icm42600_state *st)
 	const char *name;
 	struct inv_icm42600_timestamp *ts;
 	struct iio_dev *indio_dev;
-	struct iio_buffer *buffer;
 	int ret;
 
 	name = devm_kasprintf(dev, GFP_KERNEL, "%s-gyro", st->name);
@@ -731,23 +730,23 @@ struct iio_dev *inv_icm42600_gyro_init(struct inv_icm42600_state *st)
 	if (!indio_dev)
 		return ERR_PTR(-ENOMEM);
 
-	buffer = devm_iio_kfifo_allocate(dev);
-	if (!buffer)
-		return ERR_PTR(-ENOMEM);
-
 	ts = iio_priv(indio_dev);
 	inv_icm42600_timestamp_init(ts, inv_icm42600_odr_to_period(st->conf.gyro.odr));
 
 	iio_device_set_drvdata(indio_dev, st);
 	indio_dev->name = name;
 	indio_dev->info = &inv_icm42600_gyro_info;
-	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
+	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->channels = inv_icm42600_gyro_channels;
 	indio_dev->num_channels = ARRAY_SIZE(inv_icm42600_gyro_channels);
 	indio_dev->available_scan_masks = inv_icm42600_gyro_scan_masks;
 	indio_dev->setup_ops = &inv_icm42600_buffer_ops;
 
-	iio_device_attach_buffer(indio_dev, buffer);
+	ret = devm_iio_kfifo_buffer_setup(dev, indio_dev,
+					  INDIO_BUFFER_SOFTWARE,
+					  &inv_icm42600_buffer_ops);
+	if (ret)
+		return ERR_PTR(ret);
 
 	ret = devm_iio_device_register(dev, indio_dev);
 	if (ret)
diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
index 4377047d503a..fc5a60fcfec0 100644
--- a/drivers/iio/imu/kmx61.c
+++ b/drivers/iio/imu/kmx61.c
@@ -1268,7 +1268,6 @@ static struct iio_trigger *kmx61_trigger_setup(struct kmx61_data *data,
 	if (!trig)
 		return ERR_PTR(-ENOMEM);
 
-	trig->dev.parent = &data->client->dev;
 	trig->ops = &kmx61_trigger_ops;
 	iio_trigger_set_drvdata(trig, indio_dev);
 
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
index f1103ecedd64..16730a780964 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
@@ -739,20 +739,17 @@ static const struct iio_buffer_setup_ops st_lsm6dsx_buffer_ops = {
 
 int st_lsm6dsx_fifo_setup(struct st_lsm6dsx_hw *hw)
 {
-	struct iio_buffer *buffer;
-	int i;
+	int i, ret;
 
 	for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
 		if (!hw->iio_devs[i])
 			continue;
 
-		buffer = devm_iio_kfifo_allocate(hw->dev);
-		if (!buffer)
-			return -ENOMEM;
-
-		iio_device_attach_buffer(hw->iio_devs[i], buffer);
-		hw->iio_devs[i]->modes |= INDIO_BUFFER_SOFTWARE;
-		hw->iio_devs[i]->setup_ops = &st_lsm6dsx_buffer_ops;
+		ret = devm_iio_kfifo_buffer_setup(hw->dev, hw->iio_devs[i],
+						  INDIO_BUFFER_SOFTWARE,
+						  &st_lsm6dsx_buffer_ops);
+		if (ret)
+			return ret;
 	}
 
 	return 0;
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
index ec8d4351390a..8b4fc2c15622 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
@@ -29,8 +29,7 @@ static int st_lsm6dsx_i2c_probe(struct i2c_client *client,
 
 	regmap = devm_regmap_init_i2c(client, &st_lsm6dsx_i2c_regmap_config);
 	if (IS_ERR(regmap)) {
-		dev_err(&client->dev, "Failed to register i2c regmap %d\n",
-			(int)PTR_ERR(regmap));
+		dev_err(&client->dev, "Failed to register i2c regmap %ld\n", PTR_ERR(regmap));
 		return PTR_ERR(regmap);
 	}
 
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i3c.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i3c.c
index 57e633121bdc..8d4201b86e87 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i3c.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i3c.c
@@ -34,8 +34,7 @@ static int st_lsm6dsx_i3c_probe(struct i3c_device *i3cdev)
 
 	regmap = devm_regmap_init_i3c(i3cdev, &st_lsm6dsx_i3c_regmap_config);
 	if (IS_ERR(regmap)) {
-		dev_err(&i3cdev->dev, "Failed to register i3c regmap %d\n",
-			(int)PTR_ERR(regmap));
+		dev_err(&i3cdev->dev, "Failed to register i3c regmap %ld\n", PTR_ERR(regmap));
 		return PTR_ERR(regmap);
 	}
 
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c
index 349ec9c1890d..e80110b6b280 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c
@@ -29,8 +29,7 @@ static int st_lsm6dsx_spi_probe(struct spi_device *spi)
 
 	regmap = devm_regmap_init_spi(spi, &st_lsm6dsx_spi_regmap_config);
 	if (IS_ERR(regmap)) {
-		dev_err(&spi->dev, "Failed to register spi regmap %d\n",
-			(int)PTR_ERR(regmap));
+		dev_err(&spi->dev, "Failed to register spi regmap %ld\n", PTR_ERR(regmap));
 		return PTR_ERR(regmap);
 	}