Handle invalid baro pressure values

[haslinghuis]

Fixes: #12744

[blckmn]

AUTOMERGE: (FAIL)

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[ledvinap]

NaN source shall be fixed

[ledvinap]

Hmm ... only change to get NaN is in pressureToAltitude, by passing negative pressure.
So either check for negative result in ms5611 (https://github.com/betaflight/betaflight/blob/master/src/main/drivers/barometer/barometer_ms5611.c#L195) or in/before pressureToAltitude

[haslinghuis]

Should we drop the call to pressureToAltitude if pressure is negative or should we set it to 0 and let it calculate?
Also like to have root cause analysis as this was not an issue in 4.3.

[Neolight79]

Tested these changes on 4.4.1 - barometer MS5611 works well. (4.5.0 does not see any of the devices at all, but this is not relevant to these changes)
Thanks a lot @haslinghuis and @ledvinap

[ledvinap]

Looks good.

Now, someone should investigate why is ms5611 returning bad values shortly after initialization and make sure that negative/zero pressure is always returned in that case.

[ledvinap]

Can someone open MS5611 issue?

One possible way to investigate MS5611 problem is to dump I2C traffic (Saleae). If dump is available, I can look at it.

[Neolight79]

Can someone open MS5611 issue?

One possible way to investigate MS5611 problem is to dump I2C traffic (Saleae). If dump is available, I can look at it.

Well, this is interesting task, but I'm not fast in such projects. Anyway, I'll order board for Saleae and try to dump and analyze data. It won't fast. I'll be back when I'll have useful info.

[github-actions]

Do you want to test this code? Here you have an automated build:
Assets
WARNING: It may be unstable. Use only for testing! See: https://www.youtube.com/watch?v=I1uN9CN30gw for instructions for unified targets!

[Neolight79]

Can someone open MS5611 issue?

One possible way to investigate MS5611 problem is to dump I2C traffic (Saleae). If dump is available, I can look at it.

@ledvinap I've found what wrong data exactly is coming from MS5611. The way I did it is simple: first of all I found the number of wrong values - it is always 1, I simply added the counter of wrong values and put this number to DEBUG_SET(DEBUG_BARO, 0, WrongNumbersCount);.
The second step was to split int32_t into two int_t and put them into other debug variables:

DEBUG_SET(DEBUG_BARO, 1, (int)(WrongValue>>16));
DEBUG_SET(DEBUG_BARO, 2, (int)(WrongValue&65535));

This number obviosly is not changing in time, but I'm receiving different least significant part after every reset. I made 6 resets and received the following wrong pressure values:

1111 1111 1111 1010 | 1111 1011 1011 1000
1111 1111 1111 1010 | 1111 1010 1000 1010
1111 1111 1111 1010 | 1111 1001 1111 0110
1111 1111 1111 1010 | 1111 1001 1101 1011
1111 1111 1111 1010 | 1111 1010 0101 1100
1111 1111 1111 1010 | 1111 1010 1010 0011

Five most significant octets are not changing. Only three least significant octets are changing.
Hope it will help.
Thanks a lot!