drivers/media/pci/bt8xx/dst_ca.c

File Facts

System

Linux kernel

Corpus path

drivers/media/pci/bt8xx/dst_ca.c

Extension

.c

Size

19727 bytes

Lines

676

Domain

Driver Families

Bucket

drivers/media

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.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/kernel.h
• linux/module.h
• linux/slab.h
• linux/init.h
• linux/mutex.h
• linux/string.h
• linux/dvb/ca.h
• media/dvbdev.h
• media/dvb_frontend.h
• dst_ca.h
• dst_common.h

Detected Declarations

• function Copyright
• function put_command_and_length
• function put_checksum
• function dst_ci_command
• function dst_put_ci
• function ca_get_app_info
• function ca_get_ca_info
• function ca_get_slot_caps
• function ca_get_slot_descr
• function ca_get_slot_info
• function ca_get_message
• function handle_dst_tag
• function write_to_8820
• function asn_1_decode
• function debug_string
• function ca_set_pmt
• function dst_check_ca_pmt
• function ca_send_message
• function dst_ca_ioctl
• function dst_ca_open
• function dst_ca_release
• function dst_ca_read
• function dst_ca_write
• export dst_ca_attach

Annotated Snippet

static const struct file_operations dst_ca_fops = {
	.owner = THIS_MODULE,
	.unlocked_ioctl = dst_ca_ioctl,
	.open = dst_ca_open,
	.release = dst_ca_release,
	.read = dst_ca_read,
	.write = dst_ca_write,
	.llseek = noop_llseek,
};

static struct dvb_device dvbdev_ca = {
	.priv = NULL,
	.users = 1,
	.readers = 1,
	.writers = 1,
	.fops = &dst_ca_fops
};

struct dvb_device *dst_ca_attach(struct dst_state *dst, struct dvb_adapter *dvb_adapter)
{
	struct dvb_device *dvbdev;

	dprintk(verbose, DST_CA_ERROR, 1, "registering DST-CA device");
	if (dvb_register_device(dvb_adapter, &dvbdev, &dvbdev_ca, dst,
				DVB_DEVICE_CA, 0) == 0) {
		dst->dst_ca = dvbdev;
		return dst->dst_ca;
	}

	return NULL;
}

EXPORT_SYMBOL_GPL(dst_ca_attach);

MODULE_DESCRIPTION("DST DVB-S/T/C Combo CA driver");
MODULE_AUTHOR("Manu Abraham");
MODULE_LICENSE("GPL");

Annotation

• Immediate include surface: `linux/kernel.h`, `linux/module.h`, `linux/slab.h`, `linux/init.h`, `linux/mutex.h`, `linux/string.h`, `linux/dvb/ca.h`, `media/dvbdev.h`.
• Detected declarations: `function Copyright`, `function put_command_and_length`, `function put_checksum`, `function dst_ci_command`, `function dst_put_ci`, `function ca_get_app_info`, `function ca_get_ca_info`, `function ca_get_slot_caps`, `function ca_get_slot_descr`, `function ca_get_slot_info`.
• Atlas domain: Driver Families / drivers/media.
• 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.