drivers/media/platform/samsung/s5p-mfc/s5p_mfc_opr.c

Source file repositories/reference/linux-study-clean/drivers/media/platform/samsung/s5p-mfc/s5p_mfc_opr.c

File Facts

System
Linux kernel
Corpus path
drivers/media/platform/samsung/s5p-mfc/s5p_mfc_opr.c
Extension
.c
Size
3256 bytes
Lines
122
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.

Dependency Surface

Detected Declarations

Annotated Snippet

if (b->dma < base) {
			mfc_err("Invalid memory configuration - buffer (%pad) is below base memory address(%pad)\n",
				&b->dma, &base);
			dma_free_coherent(mem_dev, b->size, b->virt, b->dma);
			return -ENOMEM;
		}
	}

	mfc_debug(3, "Allocated addr %p %pad\n", b->virt, &b->dma);
	return 0;
no_mem:
	mfc_err("Allocating private buffer of size %zu failed\n", b->size);
	return -ENOMEM;
}

int s5p_mfc_alloc_generic_buf(struct s5p_mfc_dev *dev, unsigned int mem_ctx,
			   struct s5p_mfc_priv_buf *b)
{
	struct device *mem_dev = dev->mem_dev[mem_ctx];

	mfc_debug(3, "Allocating generic buf: %zu\n", b->size);

	b->ctx = mem_ctx;
	b->virt = dma_alloc_coherent(mem_dev, b->size, &b->dma, GFP_KERNEL);
	if (!b->virt)
		goto no_mem;

	mfc_debug(3, "Allocated addr %p %pad\n", b->virt, &b->dma);
	return 0;
no_mem:
	mfc_err("Allocating generic buffer of size %zu failed\n", b->size);
	return -ENOMEM;
}

void s5p_mfc_release_priv_buf(struct s5p_mfc_dev *dev,
			      struct s5p_mfc_priv_buf *b)
{
	if (dev->mem_virt) {
		unsigned int start = (b->dma - dev->mem_base) >> PAGE_SHIFT;
		unsigned int count = b->size >> PAGE_SHIFT;

		bitmap_clear(dev->mem_bitmap, start, count);
	} else {
		struct device *mem_dev = dev->mem_dev[b->ctx];

		dma_free_coherent(mem_dev, b->size, b->virt, b->dma);
	}
	b->virt = NULL;
	b->dma = 0;
	b->size = 0;
}

void s5p_mfc_release_generic_buf(struct s5p_mfc_dev *dev,
			      struct s5p_mfc_priv_buf *b)
{
	struct device *mem_dev = dev->mem_dev[b->ctx];
	dma_free_coherent(mem_dev, b->size, b->virt, b->dma);
	b->virt = NULL;
	b->dma = 0;
	b->size = 0;
}

Annotation

Implementation Notes