drivers/gpu/drm/nouveau/nvkm/subdev/i2c/pad.c

File Facts

System

Linux kernel

Corpus path

drivers/gpu/drm/nouveau/nvkm/subdev/i2c/pad.c

Extension

.c

Size

3144 bytes

Lines

117

Domain

Driver Families

Bucket

drivers/gpu

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.
• 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

• pad.h

Detected Declarations

• function files
• function nvkm_i2c_pad_mode
• function nvkm_i2c_pad_release
• function nvkm_i2c_pad_acquire
• function nvkm_i2c_pad_fini
• function nvkm_i2c_pad_init
• function nvkm_i2c_pad_del
• function nvkm_i2c_pad_ctor
• function nvkm_i2c_pad_new_

Annotated Snippet

if (pad->mode != NVKM_I2C_PAD_OFF) {
			mutex_unlock(&pad->mutex);
			return -EBUSY;
		}
		nvkm_i2c_pad_mode_locked(pad, mode);
	}
	return 0;
}

void
nvkm_i2c_pad_fini(struct nvkm_i2c_pad *pad)
{
	PAD_TRACE(pad, "fini");
	nvkm_i2c_pad_mode_locked(pad, NVKM_I2C_PAD_OFF);
}

void
nvkm_i2c_pad_init(struct nvkm_i2c_pad *pad)
{
	PAD_TRACE(pad, "init");
	nvkm_i2c_pad_mode_locked(pad, pad->mode);
}

void
nvkm_i2c_pad_del(struct nvkm_i2c_pad **ppad)
{
	struct nvkm_i2c_pad *pad = *ppad;
	if (pad) {
		PAD_TRACE(pad, "dtor");
		list_del(&pad->head);
		kfree(pad);
		pad = NULL;
	}
}

void
nvkm_i2c_pad_ctor(const struct nvkm_i2c_pad_func *func, struct nvkm_i2c *i2c,
		  int id, struct nvkm_i2c_pad *pad)
{
	pad->func = func;
	pad->i2c = i2c;
	pad->id = id;
	pad->mode = NVKM_I2C_PAD_OFF;
	mutex_init(&pad->mutex);
	list_add_tail(&pad->head, &i2c->pad);
	PAD_TRACE(pad, "ctor");
}

int
nvkm_i2c_pad_new_(const struct nvkm_i2c_pad_func *func, struct nvkm_i2c *i2c,
		  int id, struct nvkm_i2c_pad **ppad)
{
	if (!(*ppad = kzalloc_obj(**ppad)))
		return -ENOMEM;
	nvkm_i2c_pad_ctor(func, i2c, id, *ppad);
	return 0;
}

Annotation

• Immediate include surface: `pad.h`.
• Detected declarations: `function files`, `function nvkm_i2c_pad_mode`, `function nvkm_i2c_pad_release`, `function nvkm_i2c_pad_acquire`, `function nvkm_i2c_pad_fini`, `function nvkm_i2c_pad_init`, `function nvkm_i2c_pad_del`, `function nvkm_i2c_pad_ctor`, `function nvkm_i2c_pad_new_`.
• Atlas domain: Driver Families / drivers/gpu.
• Implementation status: source implementation candidate.
• 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.