Re: Cinergy T2 stopped working with kernel 2.6.30

[emagick@magic.ms]

I think I've found the problem:

------------------------------------------------------------------------
static int cinergyt2_fe_set_frontend(struct dvb_frontend *fe,
				  struct dvb_frontend_parameters *fep)
{
	struct cinergyt2_fe_state *state = fe->demodulator_priv;
	struct dvbt_set_parameters_msg param;
	char result[2];
	int err;

	param.cmd = CINERGYT2_EP1_SET_TUNER_PARAMETERS;
	param.tps = cpu_to_le16(compute_tps(fep));
	param.freq = cpu_to_le32(fep->frequency / 1000);
	param.bandwidth = 8 - fep->u.ofdm.bandwidth - BANDWIDTH_8_MHZ;

	err = dvb_usb_generic_rw(state->d,
			(char *)&param, sizeof(param),
			result, sizeof(result), 0);
------------------------------------------------------------------------

As dvbt_set_parameters_msg is declared with __attribute__((packed)), its
alignment is 8 bits.  In fact, cinergyt2_fe_set_frontend()'s param variable
is not aligned on a 32-bit boundary. Note that param is passed to usb_bulk_msg().
This seems to cause DMA problems on my hardware (Atom N270 + 945GSE + ICH7M).

I hope that I'm not talking to a black hole.