drivers/media/platform/rockchip/rkvdec/rkvdec-bitwriter.h

File Facts

System

Linux kernel

Corpus path

drivers/media/platform/rockchip/rkvdec/rkvdec-bitwriter.h

Extension

.h

Size

918 bytes

Lines

40

Domain

Driver Families

Bucket

drivers/media

Inferred role

Driver Families: implementation source

Status

source 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 or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/types.h
• linux/bits.h

Detected Declarations

• struct rkvdec_bw_field
• function rkvdec_set_bw_field

Annotated Snippet

struct rkvdec_bw_field {
	u16 offset;
	u8 len;
};

#define BW_FIELD(_offset, _len) ((struct rkvdec_bw_field){ _offset, _len })

static inline void rkvdec_set_bw_field(u32 *buf, struct rkvdec_bw_field field, u32 value)
{
	u8 bit = field.offset % 32;
	u16 word = field.offset / 32;
	u64 mask = GENMASK_ULL(bit + field.len - 1, bit);
	u64 val = ((u64)value << bit) & mask;

	buf[word] &= ~mask;
	buf[word] |= val;
	if (bit + field.len > 32) {
		buf[word + 1] &= ~(mask >> 32);
		buf[word + 1] |= val >> 32;
	}
}

#endif /* RKVDEC_BIT_WRITER_H_ */

Annotation

• Immediate include surface: `linux/types.h`, `linux/bits.h`.
• Detected declarations: `struct rkvdec_bw_field`, `function rkvdec_set_bw_field`.
• Atlas domain: Driver Families / drivers/media.
• Implementation status: source implementation candidate.

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.