drivers/acpi/ec_sys.c

File Facts

System

Linux kernel

Corpus path

drivers/acpi/ec_sys.c

Extension

.c

Size

3227 bytes

Lines

145

Domain

Driver Families

Bucket

drivers/acpi

Inferred role

Driver Families: operation-table or driver-model contract

Status

pattern implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

• Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
• Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/kernel.h
• linux/acpi.h
• linux/debugfs.h
• linux/module.h
• linux/uaccess.h
• internal.h

Detected Declarations

• function acpi_ec_read_io
• function acpi_ec_write_io
• function acpi_ec_add_debugfs
• function acpi_ec_sys_init
• function acpi_ec_sys_exit
• module init acpi_ec_sys_init

Annotated Snippet

static const struct file_operations acpi_ec_io_ops = {
	.owner = THIS_MODULE,
	.open  = simple_open,
	.read  = acpi_ec_read_io,
	.write = acpi_ec_write_io,
	.llseek = default_llseek,
};

static void acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count)
{
	struct dentry *dev_dir;
	char name[64];
	umode_t mode = 0400;

	if (ec_device_count == 0)
		acpi_ec_debugfs_dir = debugfs_create_dir("ec", NULL);

	sprintf(name, "ec%u", ec_device_count);
	dev_dir = debugfs_create_dir(name, acpi_ec_debugfs_dir);

	debugfs_create_x32("gpe", 0444, dev_dir, &first_ec->gpe);
	debugfs_create_bool("use_global_lock", 0444, dev_dir,
			    &first_ec->global_lock);

	if (write_support)
		mode = 0600;
	debugfs_create_file("io", mode, dev_dir, ec, &acpi_ec_io_ops);
}

static int __init acpi_ec_sys_init(void)
{
	if (first_ec)
		acpi_ec_add_debugfs(first_ec, 0);
	return 0;
}

static void __exit acpi_ec_sys_exit(void)
{
	debugfs_remove_recursive(acpi_ec_debugfs_dir);
}

module_init(acpi_ec_sys_init);
module_exit(acpi_ec_sys_exit);

Annotation

• Immediate include surface: `linux/kernel.h`, `linux/acpi.h`, `linux/debugfs.h`, `linux/module.h`, `linux/uaccess.h`, `internal.h`.
• Detected declarations: `function acpi_ec_read_io`, `function acpi_ec_write_io`, `function acpi_ec_add_debugfs`, `function acpi_ec_sys_init`, `function acpi_ec_sys_exit`, `module init acpi_ec_sys_init`.
• Atlas domain: Driver Families / drivers/acpi.
• Implementation status: pattern implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.