1 files changed, 122 insertions, 35 deletions

diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c
index ea8a4146620..3383b025f62 100644
--- a/drivers/iio/industrialio-trigger.c
+++ b/drivers/iio/industrialio-trigger.c
@@ -55,25 +55,16 @@ static struct attribute *iio_trig_dev_attrs[] = {
 	&dev_attr_name.attr,
 	NULL,
 };
-
-static struct attribute_group iio_trig_attr_group = {
-	.attrs	= iio_trig_dev_attrs,
-};
-
-static const struct attribute_group *iio_trig_attr_groups[] = {
-	&iio_trig_attr_group,
-	NULL
-};
+ATTRIBUTE_GROUPS(iio_trig_dev);
 
 int iio_trigger_register(struct iio_trigger *trig_info)
 {
 	int ret;
 
 	trig_info->id = ida_simple_get(&iio_trigger_ida, 0, 0, GFP_KERNEL);
-	if (trig_info->id < 0) {
-		ret = trig_info->id;
-		goto error_ret;
-	}
+	if (trig_info->id < 0)
+		return trig_info->id;
+
 	/* Set the name used for the sysfs directory etc */
 	dev_set_name(&trig_info->dev, "trigger%ld",
 		     (unsigned long) trig_info->id);
@@ -91,7 +82,6 @@ int iio_trigger_register(struct iio_trigger *trig_info)
 
 error_unregister_id:
 	ida_simple_remove(&iio_trigger_ida, trig_info->id);
-error_ret:
 	return ret;
 }
 EXPORT_SYMBOL(iio_trigger_register);
@@ -127,12 +117,17 @@ static struct iio_trigger *iio_trigger_find_by_name(const char *name,
 void iio_trigger_poll(struct iio_trigger *trig, s64 time)
 {
 	int i;
-	if (!trig->use_count)
-		for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++)
-			if (trig->subirqs[i].enabled) {
-				trig->use_count++;
+
+	if (!atomic_read(&trig->use_count)) {
+		atomic_set(&trig->use_count, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
+
+		for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
+			if (trig->subirqs[i].enabled)
 				generic_handle_irq(trig->subirq_base + i);
-			}
+			else
+				iio_trigger_notify_done(trig);
+		}
+	}
 }
 EXPORT_SYMBOL(iio_trigger_poll);
 
@@ -146,19 +141,24 @@ EXPORT_SYMBOL(iio_trigger_generic_data_rdy_poll);
 void iio_trigger_poll_chained(struct iio_trigger *trig, s64 time)
 {
 	int i;
-	if (!trig->use_count)
-		for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++)
-			if (trig->subirqs[i].enabled) {
-				trig->use_count++;
+
+	if (!atomic_read(&trig->use_count)) {
+		atomic_set(&trig->use_count, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
+
+		for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
+			if (trig->subirqs[i].enabled)
 				handle_nested_irq(trig->subirq_base + i);
-			}
+			else
+				iio_trigger_notify_done(trig);
+		}
+	}
 }
 EXPORT_SYMBOL(iio_trigger_poll_chained);
 
 void iio_trigger_notify_done(struct iio_trigger *trig)
 {
-	trig->use_count--;
-	if (trig->use_count == 0 && trig->ops && trig->ops->try_reenable)
+	if (atomic_dec_and_test(&trig->use_count) && trig->ops &&
+		trig->ops->try_reenable)
 		if (trig->ops->try_reenable(trig))
 			/* Missed an interrupt so launch new poll now */
 			iio_trigger_poll(trig, 0);
@@ -232,13 +232,12 @@ static int iio_trigger_detach_poll_func(struct iio_trigger *trig,
 	if (trig->ops && trig->ops->set_trigger_state && no_other_users) {
 		ret = trig->ops->set_trigger_state(trig, false);
 		if (ret)
-			goto error_ret;
+			return ret;
 	}
 	iio_trigger_put_irq(trig, pf->irq);
 	free_irq(pf->irq, pf);
 	module_put(pf->indio_dev->info->driver_module);
 
-error_ret:
 	return ret;
 }
 
@@ -308,7 +307,7 @@ static ssize_t iio_trigger_read_current(struct device *dev,
  * iio_trigger_write_current() - trigger consumer sysfs set current trigger
  *
  * For trigger consumers the current_trigger interface allows the trigger
- * used for this device to be specified at run time based on the triggers
+ * used for this device to be specified at run time based on the trigger's
  * name.
  **/
 static ssize_t iio_trigger_write_current(struct device *dev,
@@ -346,7 +345,7 @@ static ssize_t iio_trigger_write_current(struct device *dev,
 
 	indio_dev->trig = trig;
 
-	if (oldtrig && indio_dev->trig != oldtrig)
+	if (oldtrig)
 		iio_trigger_put(oldtrig);
 	if (indio_dev->trig)
 		iio_trigger_get(indio_dev->trig);
@@ -393,7 +392,7 @@ static void iio_trig_release(struct device *device)
 
 static struct device_type iio_trig_type = {
 	.release = iio_trig_release,
-	.groups = iio_trig_attr_groups,
+	.groups = iio_trig_dev_groups,
 };
 
 static void iio_trig_subirqmask(struct irq_data *d)
@@ -414,9 +413,8 @@ static void iio_trig_subirqunmask(struct irq_data *d)
 	trig->subirqs[d->irq - trig->subirq_base].enabled = true;
 }
 
-struct iio_trigger *iio_trigger_alloc(const char *fmt, ...)
+static struct iio_trigger *viio_trigger_alloc(const char *fmt, va_list vargs)
 {
-	va_list vargs;
 	struct iio_trigger *trig;
 	trig = kzalloc(sizeof *trig, GFP_KERNEL);
 	if (trig) {
@@ -434,9 +432,8 @@ struct iio_trigger *iio_trigger_alloc(const char *fmt, ...)
 			kfree(trig);
 			return NULL;
 		}
-		va_start(vargs, fmt);
+
 		trig->name = kvasprintf(GFP_KERNEL, fmt, vargs);
-		va_end(vargs);
 		if (trig->name == NULL) {
 			irq_free_descs(trig->subirq_base,
 				       CONFIG_IIO_CONSUMERS_PER_TRIGGER);
@@ -457,6 +454,19 @@ struct iio_trigger *iio_trigger_alloc(const char *fmt, ...)
 		}
 		get_device(&trig->dev);
 	}
+
+	return trig;
+}
+
+struct iio_trigger *iio_trigger_alloc(const char *fmt, ...)
+{
+	struct iio_trigger *trig;
+	va_list vargs;
+
+	va_start(vargs, fmt);
+	trig = viio_trigger_alloc(fmt, vargs);
+	va_end(vargs);
+
 	return trig;
 }
 EXPORT_SYMBOL(iio_trigger_alloc);
@@ -468,6 +478,83 @@ void iio_trigger_free(struct iio_trigger *trig)
 }
 EXPORT_SYMBOL(iio_trigger_free);
 
+static void devm_iio_trigger_release(struct device *dev, void *res)
+{
+	iio_trigger_free(*(struct iio_trigger **)res);
+}
+
+static int devm_iio_trigger_match(struct device *dev, void *res, void *data)
+{
+	struct iio_trigger **r = res;
+
+	if (!r || !*r) {
+		WARN_ON(!r || !*r);
+		return 0;
+	}
+
+	return *r == data;
+}
+
+/**
+ * devm_iio_trigger_alloc - Resource-managed iio_trigger_alloc()
+ * @dev:		Device to allocate iio_trigger for
+ * @fmt:		trigger name format. If it includes format
+ *			specifiers, the additional arguments following
+ *			format are formatted and inserted in the resulting
+ *			string replacing their respective specifiers.
+ *
+ * Managed iio_trigger_alloc.  iio_trigger allocated with this function is
+ * automatically freed on driver detach.
+ *
+ * If an iio_trigger allocated with this function needs to be freed separately,
+ * devm_iio_trigger_free() must be used.
+ *
+ * RETURNS:
+ * Pointer to allocated iio_trigger on success, NULL on failure.
+ */
+struct iio_trigger *devm_iio_trigger_alloc(struct device *dev,
+						const char *fmt, ...)
+{
+	struct iio_trigger **ptr, *trig;
+	va_list vargs;
+
+	ptr = devres_alloc(devm_iio_trigger_release, sizeof(*ptr),
+			   GFP_KERNEL);
+	if (!ptr)
+		return NULL;
+
+	/* use raw alloc_dr for kmalloc caller tracing */
+	va_start(vargs, fmt);
+	trig = viio_trigger_alloc(fmt, vargs);
+	va_end(vargs);
+	if (trig) {
+		*ptr = trig;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return trig;
+}
+EXPORT_SYMBOL_GPL(devm_iio_trigger_alloc);
+
+/**
+ * devm_iio_trigger_free - Resource-managed iio_trigger_free()
+ * @dev:		Device this iio_dev belongs to
+ * @iio_trig:		the iio_trigger associated with the device
+ *
+ * Free iio_trigger allocated with devm_iio_trigger_alloc().
+ */
+void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig)
+{
+	int rc;
+
+	rc = devres_release(dev, devm_iio_trigger_release,
+			    devm_iio_trigger_match, iio_trig);
+	WARN_ON(rc);
+}
+EXPORT_SYMBOL_GPL(devm_iio_trigger_free);
+
 void iio_device_register_trigger_consumer(struct iio_dev *indio_dev)
 {
 	indio_dev->groups[indio_dev->groupcounter++] =