On 01/16/2018 10:14 PM, Brad Love wrote:
On 2018-01-16 13:32, Antti Palosaari wrote:
On 01/16/2018 07:31 PM, Brad Love wrote:
On 2018-01-15 23:07, Antti Palosaari wrote:
Hello
And what is rationale here, is there some use case demod must be
active and ts set to tristate (disabled)? Just put demod sleep when
you don't use it.
regards
Antti
Hello Antti,
Perhaps the .ts_bus_ctrl callback does not need to be included in ops,
but the function is necessary. The demod is already put to sleep when
not in use, but it leaves the ts bus open. The ts bus has no reason to
be open when the demod is put to sleep. Leaving the ts bus open during
sleep affects the other connected demod and nothing is received by it.
The lgdt3306a driver already tri states its ts bus when put to sleep,
the si2168 should as well.
Sounds possible, but unlikely as chip is firmware driven. When you put
chip to sleep you usually want set ts pins to tristate (also other
unused pins) in order to save energy. I haven't never tested it anyway
though, so it could be possible it leaves those pins to some other
state like random output at given time.
And if you cannot get stream from lgdt3306a, which is connected to
same bus, it really sounds like ts bus pins are left some state
(cannot work if same pin is driven high to other demod whilst other
tries to drive it low.
Setting ts pins to tri-state during sleep should resolve your issue.
Hello Antti,
This patch fixes the issue I'm describing, hence why I submitted it. The
ts bus must be tristated before putting the chip to sleep for the other
demod to get a stream.
I can test tri-state using power meter on some day, but it may be so
small current that it cannot be seen usb power meter I use (YZXstudio,
very nice small power meter).
regards
Antti
--
http://palosaari.fi/
