On 2018-01-16 14:38, Antti Palosaari wrote: > 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 > Nifty looking devices, one just fell into my shopping cart :) Cheers, Brad
