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
  ...

1 files changed, 97 insertions, 35 deletions

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 7db761afa578..b5750edf935c 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -157,6 +157,7 @@ static const char * const iio_chan_info_postfix[] = {
 	[IIO_CHAN_INFO_PHASE] = "phase",
 	[IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
 	[IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
+	[IIO_CHAN_INFO_HYSTERESIS_RELATIVE] = "hysteresis_relative",
 	[IIO_CHAN_INFO_INT_TIME] = "integration_time",
 	[IIO_CHAN_INFO_ENABLE] = "en",
 	[IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
@@ -625,7 +626,6 @@ EXPORT_SYMBOL(iio_read_mount_matrix);
 static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
 				  int size, const int *vals)
 {
-	unsigned long long tmp;
 	int tmp0, tmp1;
 	s64 tmp2;
 	bool scale_db = false;
@@ -658,9 +658,12 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
 		else
 			return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
 	case IIO_VAL_FRACTIONAL_LOG2:
-		tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
-		tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1);
-		return scnprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
+		tmp2 = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
+		tmp0 = (int)div_s64_rem(tmp2, 1000000000LL, &tmp1);
+		if (tmp0 == 0 && tmp2 < 0)
+			return snprintf(buf, len, "-0.%09u", abs(tmp1));
+		else
+			return scnprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
 	case IIO_VAL_INT_MULTIPLE:
 	{
 		int i;
@@ -1114,6 +1117,7 @@ int __iio_add_chan_devattr(const char *postfix,
 			   u64 mask,
 			   enum iio_shared_by shared_by,
 			   struct device *dev,
+			   struct iio_buffer *buffer,
 			   struct list_head *attr_list)
 {
 	int ret;
@@ -1129,6 +1133,7 @@ int __iio_add_chan_devattr(const char *postfix,
 		goto error_iio_dev_attr_free;
 	iio_attr->c = chan;
 	iio_attr->address = mask;
+	iio_attr->buffer = buffer;
 	list_for_each_entry(t, attr_list, l)
 		if (strcmp(t->dev_attr.attr.name,
 			   iio_attr->dev_attr.attr.name) == 0) {
@@ -1165,6 +1170,7 @@ static int iio_device_add_channel_label(struct iio_dev *indio_dev,
 				     0,
 				     IIO_SEPARATE,
 				     &indio_dev->dev,
+				     NULL,
 				     &iio_dev_opaque->channel_attr_list);
 	if (ret < 0)
 		return ret;
@@ -1190,6 +1196,7 @@ static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
 					     i,
 					     shared_by,
 					     &indio_dev->dev,
+					     NULL,
 					     &iio_dev_opaque->channel_attr_list);
 		if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
 			continue;
@@ -1226,6 +1233,7 @@ static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,
 					     i,
 					     shared_by,
 					     &indio_dev->dev,
+					     NULL,
 					     &iio_dev_opaque->channel_attr_list);
 		kfree(avail_postfix);
 		if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
@@ -1322,6 +1330,7 @@ static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
 					i,
 					ext_info->shared,
 					&indio_dev->dev,
+					NULL,
 					&iio_dev_opaque->channel_attr_list);
 			i++;
 			if (ret == -EBUSY && ext_info->shared)
@@ -1349,7 +1358,7 @@ void iio_free_chan_devattr_list(struct list_head *attr_list)
 	struct iio_dev_attr *p, *n;
 
 	list_for_each_entry_safe(p, n, attr_list, l) {
-		kfree(p->dev_attr.attr.name);
+		kfree_const(p->dev_attr.attr.name);
 		list_del(&p->l);
 		kfree(p);
 	}
@@ -1452,6 +1461,25 @@ static ssize_t iio_store_timestamp_clock(struct device *dev,
 	return len;
 }
 
+int iio_device_register_sysfs_group(struct iio_dev *indio_dev,
+				    const struct attribute_group *group)
+{
+	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
+	const struct attribute_group **new, **old = iio_dev_opaque->groups;
+	unsigned int cnt = iio_dev_opaque->groupcounter;
+
+	new = krealloc(old, sizeof(*new) * (cnt + 2), GFP_KERNEL);
+	if (!new)
+		return -ENOMEM;
+
+	new[iio_dev_opaque->groupcounter++] = group;
+	new[iio_dev_opaque->groupcounter] = NULL;
+
+	iio_dev_opaque->groups = new;
+
+	return 0;
+}
+
 static DEVICE_ATTR(current_timestamp_clock, S_IRUGO | S_IWUSR,
 		   iio_show_timestamp_clock, iio_store_timestamp_clock);
 
@@ -1525,8 +1553,10 @@ static int iio_device_register_sysfs(struct iio_dev *indio_dev)
 	if (clk)
 		iio_dev_opaque->chan_attr_group.attrs[attrn++] = clk;
 
-	indio_dev->groups[indio_dev->groupcounter++] =
-		&iio_dev_opaque->chan_attr_group;
+	ret = iio_device_register_sysfs_group(indio_dev,
+					      &iio_dev_opaque->chan_attr_group);
+	if (ret)
+		goto error_clear_attrs;
 
 	return 0;
 
@@ -1543,6 +1573,7 @@ static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
 	iio_free_chan_devattr_list(&iio_dev_opaque->channel_attr_list);
 	kfree(iio_dev_opaque->chan_attr_group.attrs);
 	iio_dev_opaque->chan_attr_group.attrs = NULL;
+	kfree(iio_dev_opaque->groups);
 }
 
 static void iio_dev_release(struct device *device)
@@ -1555,7 +1586,7 @@ static void iio_dev_release(struct device *device)
 	iio_device_unregister_eventset(indio_dev);
 	iio_device_unregister_sysfs(indio_dev);
 
-	iio_buffer_put(indio_dev->buffer);
+	iio_device_detach_buffers(indio_dev);
 
 	ida_simple_remove(&iio_ida, indio_dev->id);
 	kfree(iio_dev_opaque);
@@ -1574,7 +1605,7 @@ struct device_type iio_device_type = {
 struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv)
 {
 	struct iio_dev_opaque *iio_dev_opaque;
-	struct iio_dev *dev;
+	struct iio_dev *indio_dev;
 	size_t alloc_size;
 
 	alloc_size = sizeof(struct iio_dev_opaque);
@@ -1587,32 +1618,31 @@ struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv)
 	if (!iio_dev_opaque)
 		return NULL;
 
-	dev = &iio_dev_opaque->indio_dev;
-	dev->priv = (char *)iio_dev_opaque +
+	indio_dev = &iio_dev_opaque->indio_dev;
+	indio_dev->priv = (char *)iio_dev_opaque +
 		ALIGN(sizeof(struct iio_dev_opaque), IIO_ALIGN);
 
-	dev->dev.parent = parent;
-	dev->dev.groups = dev->groups;
-	dev->dev.type = &iio_device_type;
-	dev->dev.bus = &iio_bus_type;
-	device_initialize(&dev->dev);
-	dev_set_drvdata(&dev->dev, (void *)dev);
-	mutex_init(&dev->mlock);
-	mutex_init(&dev->info_exist_lock);
+	indio_dev->dev.parent = parent;
+	indio_dev->dev.type = &iio_device_type;
+	indio_dev->dev.bus = &iio_bus_type;
+	device_initialize(&indio_dev->dev);
+	iio_device_set_drvdata(indio_dev, (void *)indio_dev);
+	mutex_init(&indio_dev->mlock);
+	mutex_init(&indio_dev->info_exist_lock);
 	INIT_LIST_HEAD(&iio_dev_opaque->channel_attr_list);
 
-	dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
-	if (dev->id < 0) {
+	indio_dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
+	if (indio_dev->id < 0) {
 		/* cannot use a dev_err as the name isn't available */
 		pr_err("failed to get device id\n");
 		kfree(iio_dev_opaque);
 		return NULL;
 	}
-	dev_set_name(&dev->dev, "iio:device%d", dev->id);
+	dev_set_name(&indio_dev->dev, "iio:device%d", indio_dev->id);
 	INIT_LIST_HEAD(&iio_dev_opaque->buffer_list);
 	INIT_LIST_HEAD(&iio_dev_opaque->ioctl_handlers);
 
-	return dev;
+	return indio_dev;
 }
 EXPORT_SYMBOL(iio_device_alloc);
 
@@ -1676,13 +1706,24 @@ static int iio_chrdev_open(struct inode *inode, struct file *filp)
 {
 	struct iio_dev *indio_dev = container_of(inode->i_cdev,
 						struct iio_dev, chrdev);
+	struct iio_dev_buffer_pair *ib;
 
 	if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
 		return -EBUSY;
 
 	iio_device_get(indio_dev);
 
-	filp->private_data = indio_dev;
+	ib = kmalloc(sizeof(*ib), GFP_KERNEL);
+	if (!ib) {
+		iio_device_put(indio_dev);
+		clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
+		return -ENOMEM;
+	}
+
+	ib->indio_dev = indio_dev;
+	ib->buffer = indio_dev->buffer;
+
+	filp->private_data = ib;
 
 	return 0;
 }
@@ -1696,8 +1737,10 @@ static int iio_chrdev_open(struct inode *inode, struct file *filp)
  */
 static int iio_chrdev_release(struct inode *inode, struct file *filp)
 {
+	struct iio_dev_buffer_pair *ib = filp->private_data;
 	struct iio_dev *indio_dev = container_of(inode->i_cdev,
 						struct iio_dev, chrdev);
+	kfree(ib);
 	clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
 	iio_device_put(indio_dev);
 
@@ -1719,7 +1762,8 @@ void iio_device_ioctl_handler_unregister(struct iio_ioctl_handler *h)
 
 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
-	struct iio_dev *indio_dev = filp->private_data;
+	struct iio_dev_buffer_pair *ib = filp->private_data;
+	struct iio_dev *indio_dev = ib->indio_dev;
 	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
 	struct iio_ioctl_handler *h;
 	int ret = -ENODEV;
@@ -1761,6 +1805,15 @@ static const struct file_operations iio_buffer_fileops = {
 	.release = iio_chrdev_release,
 };
 
+static const struct file_operations iio_event_fileops = {
+	.owner = THIS_MODULE,
+	.llseek = noop_llseek,
+	.unlocked_ioctl = iio_ioctl,
+	.compat_ioctl = compat_ptr_ioctl,
+	.open = iio_chrdev_open,
+	.release = iio_chrdev_release,
+};
+
 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
 {
 	int i, j;
@@ -1788,6 +1841,8 @@ static const struct iio_buffer_setup_ops noop_ring_setup_ops;
 
 int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
 {
+	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
+	const char *label;
 	int ret;
 
 	if (!indio_dev->info)
@@ -1798,19 +1853,17 @@ int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
 	if (!indio_dev->dev.of_node && indio_dev->dev.parent)
 		indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
 
-	indio_dev->label = of_get_property(indio_dev->dev.of_node, "label",
-					   NULL);
+	label = of_get_property(indio_dev->dev.of_node, "label", NULL);
+	if (label)
+		indio_dev->label = label;
 
 	ret = iio_check_unique_scan_index(indio_dev);
 	if (ret < 0)
 		return ret;
 
-	/* configure elements for the chrdev */
-	indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
-
 	iio_device_register_debugfs(indio_dev);
 
-	ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
+	ret = iio_buffers_alloc_sysfs_and_mask(indio_dev);
 	if (ret) {
 		dev_err(indio_dev->dev.parent,
 			"Failed to create buffer sysfs interfaces\n");
@@ -1836,9 +1889,18 @@ int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
 		indio_dev->setup_ops == NULL)
 		indio_dev->setup_ops = &noop_ring_setup_ops;
 
-	cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
+	if (iio_dev_opaque->attached_buffers_cnt)
+		cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
+	else if (iio_dev_opaque->event_interface)
+		cdev_init(&indio_dev->chrdev, &iio_event_fileops);
+
+	if (iio_dev_opaque->attached_buffers_cnt || iio_dev_opaque->event_interface) {
+		indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
+		indio_dev->chrdev.owner = this_mod;
+	}
 
-	indio_dev->chrdev.owner = this_mod;
+	/* assign device groups now; they should be all registered now */
+	indio_dev->dev.groups = iio_dev_opaque->groups;
 
 	ret = cdev_device_add(&indio_dev->chrdev, &indio_dev->dev);
 	if (ret < 0)
@@ -1851,7 +1913,7 @@ error_unreg_eventset:
 error_free_sysfs:
 	iio_device_unregister_sysfs(indio_dev);
 error_buffer_free_sysfs:
-	iio_buffer_free_sysfs_and_mask(indio_dev);
+	iio_buffers_free_sysfs_and_mask(indio_dev);
 error_unreg_debugfs:
 	iio_device_unregister_debugfs(indio_dev);
 	return ret;
@@ -1885,7 +1947,7 @@ void iio_device_unregister(struct iio_dev *indio_dev)
 
 	mutex_unlock(&indio_dev->info_exist_lock);
 
-	iio_buffer_free_sysfs_and_mask(indio_dev);
+	iio_buffers_free_sysfs_and_mask(indio_dev);
 }
 EXPORT_SYMBOL(iio_device_unregister);