drivers/media/pci/ddbridge/ddbridge-dummy-fe.c

Source file repositories/reference/linux-study-clean/drivers/media/pci/ddbridge/ddbridge-dummy-fe.c

File Facts

System
Linux kernel
Corpus path
drivers/media/pci/ddbridge/ddbridge-dummy-fe.c
Extension
.c
Size
3503 bytes
Lines
154
Domain
Driver Families
Bucket
drivers/media
Inferred role
Driver Families: exported/initcall integration point
Status
integration 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 ddbridge_dummy_fe_state {
	struct dvb_frontend frontend;
};

static int ddbridge_dummy_fe_read_status(struct dvb_frontend *fe,
				    enum fe_status *status)
{
	*status = FE_HAS_SIGNAL
		| FE_HAS_CARRIER
		| FE_HAS_VITERBI
		| FE_HAS_SYNC
		| FE_HAS_LOCK;

	return 0;
}

static int ddbridge_dummy_fe_read_ber(struct dvb_frontend *fe, u32 *ber)
{
	*ber = 0;
	return 0;
}

static int ddbridge_dummy_fe_read_signal_strength(struct dvb_frontend *fe,
					     u16 *strength)
{
	*strength = 0;
	return 0;
}

static int ddbridge_dummy_fe_read_snr(struct dvb_frontend *fe, u16 *snr)
{
	*snr = 0;
	return 0;
}

static int ddbridge_dummy_fe_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
{
	*ucblocks = 0;
	return 0;
}

/*
 * Should only be implemented if it actually reads something from the hardware.
 * Also, it should check for the locks, in order to avoid report wrong data
 * to userspace.
 */
static int ddbridge_dummy_fe_get_frontend(struct dvb_frontend *fe,
				     struct dtv_frontend_properties *p)
{
	return 0;
}

static int ddbridge_dummy_fe_set_frontend(struct dvb_frontend *fe)
{
	if (fe->ops.tuner_ops.set_params) {
		fe->ops.tuner_ops.set_params(fe);
		if (fe->ops.i2c_gate_ctrl)
			fe->ops.i2c_gate_ctrl(fe, 0);
	}

	return 0;
}

static int ddbridge_dummy_fe_sleep(struct dvb_frontend *fe)
{
	return 0;
}

static int ddbridge_dummy_fe_init(struct dvb_frontend *fe)
{
	return 0;
}

static void ddbridge_dummy_fe_release(struct dvb_frontend *fe)
{
	struct ddbridge_dummy_fe_state *state = fe->demodulator_priv;

	kfree(state);
}

static const struct dvb_frontend_ops ddbridge_dummy_fe_qam_ops;

struct dvb_frontend *ddbridge_dummy_fe_qam_attach(void)
{
	struct ddbridge_dummy_fe_state *state = NULL;

	/* allocate memory for the internal state */
	state = kzalloc_obj(struct ddbridge_dummy_fe_state);
	if (!state)
		return NULL;

Annotation

Implementation Notes