On Thursday 04 August 2005 14:03, Johannes Stezenbach wrote:
>
> For the Nebula it may be that simple, but in the general case there
> might be more work to do (e.g. first make sure the demod is not
> in sleep state, need to probe PLL seperately etc.). Every time
> there's a new Nebula version the code needs updateing and gets more
> complex...
>
Mainly as an exercise for myself, I've coded this up.
So instead of trying to attach each frontend in turn, we attempt to read a
register on the nxt6000. Basically if the i2c read succeeds, we know that
we've got the nxt6000 frontend, otherwise it's the mt352. This also isn't a
terribly clean way of doing it, but it's how Nebula do it.
As I say, this was mainly an exercise for myself to see if I could implement
it successfully, so I won't be too upset if you decide it isn't worth doing.
Here's the code (hopefully it won't get too messed up by my MUA):
int i2cret;
u8 b0[] = { 0x00 };
u8 b1[] = { 0 };
struct i2c_msg msgs[] = {
{.addr = 0x14,.flags = 0,.buf = b0,.len = 1},
{.addr = 0x14,.flags = I2C_M_RD,.buf = b1,.len = 1}
};
i2cret = i2c_transfer(card->i2c_adapter, msgs, 2);
dprintk ("dvb_bt8xx: i2c read got value %d, function returned %d\n", b1[0],
i2cret);
if (b1[0] == 0x0b) {
/* Old Nebula (marked (c)2003 on high profile pci card) has nxt6000 demod */
card->fe = nxt6000_attach(&vp3021_alps_tded4_config, card->i2c_adapter);
dprintk ("dvb_bt8xx: an nxt6000 was detected on your digitv card\n");
} else {
/* New Nebula (marked (c)2005 on low profile pci card) has mt352 demod */
digitv_alps_tded4_reset(card);
card->fe = mt352_attach(&digitv_alps_tded4_config, card->i2c_adapter);
dprintk ("dvb_bt8xx: an mt352 was detected on your digitv card\n");
}
if (card->fe == NULL)
dprintk ("dvb_bt8xx: a supported frontend was not found on your digitv
card\n");
I don't have an nxt6000-based card to test with, but the code compiles cleanly
and succeeds in reading a value from the mt352 if I change the I2C address.
If you think doing this detection is worthwhile, I'll create a patch and get
somebody to test it with an nxt6000, otherwise I'll create a patch to remove
the comment from the code and stop bothering you :-)
Regards,
David.
