drivers/accessibility/speakup/devsynth.c

File Facts

System

Linux kernel

Corpus path

drivers/accessibility/speakup/devsynth.c

Extension

.c

Size

4055 bytes

Lines

179

Domain

Driver Families

Bucket

drivers/accessibility

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.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/errno.h
• linux/miscdevice.h
• linux/types.h
• linux/uaccess.h
• speakup.h
• spk_priv.h

Detected Declarations

• function speakup_file_write
• function speakup_file_writeu
• function speakup_file_read
• function speakup_file_open
• function speakup_file_release
• function speakup_register_devsynth
• function speakup_unregister_devsynth

Annotated Snippet

static const struct file_operations synth_fops = {
	.read = speakup_file_read,
	.write = speakup_file_write,
	.open = speakup_file_open,
	.release = speakup_file_release,
};

static const struct file_operations synthu_fops = {
	.read = speakup_file_read,
	.write = speakup_file_writeu,
	.open = speakup_file_open,
	.release = speakup_file_release,
};

static struct miscdevice synth_device = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = "synth",
	.fops = &synth_fops,
};

static struct miscdevice synthu_device = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = "synthu",
	.fops = &synthu_fops,
};

void speakup_register_devsynth(void)
{
	if (!synth_registered) {
		if (misc_register(&synth_device)) {
			pr_warn("Couldn't initialize miscdevice /dev/synth.\n");
		} else {
			pr_info("initialized device: /dev/synth, node (MAJOR %d, MINOR %d)\n",
				MISC_MAJOR, synth_device.minor);
			synth_registered = 1;
		}
	}
	if (!synthu_registered) {
		if (misc_register(&synthu_device)) {
			pr_warn("Couldn't initialize miscdevice /dev/synthu.\n");
		} else {
			pr_info("initialized device: /dev/synthu, node (MAJOR %d, MINOR %d)\n",
				MISC_MAJOR, synthu_device.minor);
			synthu_registered = 1;
		}
	}
}

void speakup_unregister_devsynth(void)
{
	if (synth_registered) {
		pr_info("speakup: unregistering synth device /dev/synth\n");
		misc_deregister(&synth_device);
		synth_registered = 0;
	}
	if (synthu_registered) {
		pr_info("speakup: unregistering synth device /dev/synthu\n");
		misc_deregister(&synthu_device);
		synthu_registered = 0;
	}
}

Annotation

• Immediate include surface: `linux/errno.h`, `linux/miscdevice.h`, `linux/types.h`, `linux/uaccess.h`, `speakup.h`, `spk_priv.h`.
• Detected declarations: `function speakup_file_write`, `function speakup_file_writeu`, `function speakup_file_read`, `function speakup_file_open`, `function speakup_file_release`, `function speakup_register_devsynth`, `function speakup_unregister_devsynth`.
• Atlas domain: Driver Families / drivers/accessibility.
• Implementation status: pattern implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

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.