new file mode 100644
@@ -0,0 +1,9 @@
+What: /sys/bus/auxiliary/devices/.../irqs/
+Date: April, 2024
+Contact: Shay Drory <shayd@nvidia.com>
+Description:
+ The /sys/devices/.../irqs directory contains a variable set of
+ files, with each file is named as irq number similar to PCI PF
+ or VF's irq number located in msi_irqs directory.
+ These irq files are added and removed dynamically when an IRQ
+ is requested and freed respectively for the PCI SF.
@@ -16,6 +16,7 @@ obj-$(CONFIG_NUMA) += node.o
obj-$(CONFIG_MEMORY_HOTPLUG) += memory.o
ifeq ($(CONFIG_SYSFS),y)
obj-$(CONFIG_MODULES) += module.o
+obj-$(CONFIG_AUXILIARY_BUS) += auxiliary_sysfs.o
endif
obj-$(CONFIG_SYS_HYPERVISOR) += hypervisor.o
obj-$(CONFIG_REGMAP) += regmap/
@@ -287,6 +287,7 @@ int auxiliary_device_init(struct auxiliary_device *auxdev)
dev->bus = &auxiliary_bus_type;
device_initialize(&auxdev->dev);
+ mutex_init(&auxdev->lock);
return 0;
}
EXPORT_SYMBOL_GPL(auxiliary_device_init);
new file mode 100644
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2024, NVIDIA CORPORATION & AFFILIATES
+ */
+
+#include <linux/auxiliary_bus.h>
+#include <linux/slab.h>
+
+struct auxiliary_irq_info {
+ struct device_attribute sysfs_attr;
+};
+
+static struct attribute *auxiliary_irq_attrs[] = {
+ NULL
+};
+
+static const struct attribute_group auxiliary_irqs_group = {
+ .name = "irqs",
+ .attrs = auxiliary_irq_attrs,
+};
+
+static int auxiliary_irq_dir_prepare(struct auxiliary_device *auxdev)
+{
+ int ret = 0;
+
+ mutex_lock(&auxdev->lock);
+ if (auxdev->irq_dir_exists)
+ goto unlock;
+
+ ret = devm_device_add_group(&auxdev->dev, &auxiliary_irqs_group);
+ if (ret)
+ goto unlock;
+
+ auxdev->irq_dir_exists = true;
+ xa_init(&auxdev->irqs);
+unlock:
+ mutex_unlock(&auxdev->lock);
+ return ret;
+}
+
+/**
+ * auxiliary_device_sysfs_irq_add - add a sysfs entry for the given IRQ
+ * @auxdev: auxiliary bus device to add the sysfs entry.
+ * @irq: The associated interrupt number.
+ *
+ * This function should be called after auxiliary device have successfully
+ * received the irq.
+ * The driver is responsible to add a unique irq for the auxiliary device. The
+ * driver can invoke this function from multiple thread context safely for
+ * unique irqs of the auxiliary devices. The driver must not invoke this API
+ * multiple times if the irq is already added previously.
+ *
+ * Return: zero on success or an error code on failure.
+ */
+int auxiliary_device_sysfs_irq_add(struct auxiliary_device *auxdev, int irq)
+{
+ struct auxiliary_irq_info *info __free(kfree) = NULL;
+ struct device *dev = &auxdev->dev;
+ char *name __free(kfree) = NULL;
+ int ret;
+
+ ret = auxiliary_irq_dir_prepare(auxdev);
+ if (ret)
+ return ret;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ sysfs_attr_init(&info->sysfs_attr.attr);
+ name = kasprintf(GFP_KERNEL, "%d", irq);
+ if (!name)
+ return -ENOMEM;
+
+ ret = xa_insert(&auxdev->irqs, irq, info, GFP_KERNEL);
+ if (ret)
+ return ret;
+
+ info->sysfs_attr.attr.name = name;
+ ret = sysfs_add_file_to_group(&dev->kobj, &info->sysfs_attr.attr,
+ auxiliary_irqs_group.name);
+ if (ret)
+ goto sysfs_add_err;
+
+ info->sysfs_attr.attr.name = no_free_ptr(name);
+ xa_store(&auxdev->irqs, irq, no_free_ptr(info), GFP_KERNEL);
+ return 0;
+
+sysfs_add_err:
+ xa_erase(&auxdev->irqs, irq);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(auxiliary_device_sysfs_irq_add);
+
+/**
+ * auxiliary_device_sysfs_irq_remove - remove a sysfs entry for the given IRQ
+ * @auxdev: auxiliary bus device to add the sysfs entry.
+ * @irq: the IRQ to remove.
+ *
+ * This function should be called to remove an IRQ sysfs entry.
+ * The driver must invoke this API when IRQ is released by the device.
+ */
+void auxiliary_device_sysfs_irq_remove(struct auxiliary_device *auxdev, int irq)
+{
+ struct auxiliary_irq_info *info __free(kfree) = xa_load(&auxdev->irqs, irq);
+ const char *name __free(kfree) = info->sysfs_attr.attr.name;
+ struct device *dev = &auxdev->dev;
+
+ sysfs_remove_file_from_group(&dev->kobj, &info->sysfs_attr.attr,
+ auxiliary_irqs_group.name);
+ xa_erase(&auxdev->irqs, irq);
+}
+EXPORT_SYMBOL_GPL(auxiliary_device_sysfs_irq_remove);
@@ -58,6 +58,9 @@
* in
* @name: Match name found by the auxiliary device driver,
* @id: unique identitier if multiple devices of the same name are exported,
+ * @irqs: irqs xarray contains irq indices which are used by the device,
+ * @lock: Synchronize irq sysfs creation,
+ * @irq_dir_exists: whether "irqs" directory exists,
*
* An auxiliary_device represents a part of its parent device's functionality.
* It is given a name that, combined with the registering drivers
@@ -138,7 +141,10 @@
struct auxiliary_device {
struct device dev;
const char *name;
+ struct xarray irqs;
+ struct mutex lock; /* Synchronize irq sysfs creation */
u32 id;
+ bool irq_dir_exists;
};
/**
@@ -212,8 +218,24 @@ int auxiliary_device_init(struct auxiliary_device *auxdev);
int __auxiliary_device_add(struct auxiliary_device *auxdev, const char *modname);
#define auxiliary_device_add(auxdev) __auxiliary_device_add(auxdev, KBUILD_MODNAME)
+#ifdef CONFIG_SYSFS
+int auxiliary_device_sysfs_irq_add(struct auxiliary_device *auxdev, int irq);
+void auxiliary_device_sysfs_irq_remove(struct auxiliary_device *auxdev,
+ int irq);
+#else /* CONFIG_SYSFS */
+static inline int
+auxiliary_device_sysfs_irq_add(struct auxiliary_device *auxdev, int irq)
+{
+ return 0;
+}
+
+static inline void
+auxiliary_device_sysfs_irq_remove(struct auxiliary_device *auxdev, int irq) {}
+#endif
+
static inline void auxiliary_device_uninit(struct auxiliary_device *auxdev)
{
+ mutex_destroy(&auxdev->lock);
put_device(&auxdev->dev);
}