drivers/gpu/drm/nouveau/nvkm/subdev/i2c/busnv04.c

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/nouveau/nvkm/subdev/i2c/busnv04.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/nouveau/nvkm/subdev/i2c/busnv04.c
Extension
.c
Size
3054 bytes
Lines
97
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.

Dependency Surface

Detected Declarations

Annotated Snippet

struct nv04_i2c_bus {
	struct nvkm_i2c_bus base;
	u8 drive;
	u8 sense;
};

static void
nv04_i2c_bus_drive_scl(struct nvkm_i2c_bus *base, int state)
{
	struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
	u8 val = nvkm_rdvgac(device, 0, bus->drive);
	if (state) val |= 0x20;
	else	   val &= 0xdf;
	nvkm_wrvgac(device, 0, bus->drive, val | 0x01);
}

static void
nv04_i2c_bus_drive_sda(struct nvkm_i2c_bus *base, int state)
{
	struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
	u8 val = nvkm_rdvgac(device, 0, bus->drive);
	if (state) val |= 0x10;
	else	   val &= 0xef;
	nvkm_wrvgac(device, 0, bus->drive, val | 0x01);
}

static int
nv04_i2c_bus_sense_scl(struct nvkm_i2c_bus *base)
{
	struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
	return !!(nvkm_rdvgac(device, 0, bus->sense) & 0x04);
}

static int
nv04_i2c_bus_sense_sda(struct nvkm_i2c_bus *base)
{
	struct nv04_i2c_bus *bus = nv04_i2c_bus(base);
	struct nvkm_device *device = bus->base.pad->i2c->subdev.device;
	return !!(nvkm_rdvgac(device, 0, bus->sense) & 0x08);
}

static const struct nvkm_i2c_bus_func
nv04_i2c_bus_func = {
	.drive_scl = nv04_i2c_bus_drive_scl,
	.drive_sda = nv04_i2c_bus_drive_sda,
	.sense_scl = nv04_i2c_bus_sense_scl,
	.sense_sda = nv04_i2c_bus_sense_sda,
	.xfer = nvkm_i2c_bit_xfer,
};

int
nv04_i2c_bus_new(struct nvkm_i2c_pad *pad, int id, u8 drive, u8 sense,
		 struct nvkm_i2c_bus **pbus)
{
	struct nv04_i2c_bus *bus;

	if (!(bus = kzalloc_obj(*bus)))
		return -ENOMEM;
	*pbus = &bus->base;

	nvkm_i2c_bus_ctor(&nv04_i2c_bus_func, pad, id, &bus->base);
	bus->drive = drive;
	bus->sense = sense;
	return 0;
}

Annotation

Implementation Notes