I'm new in this forum and I'm coming with relatively specific question.
For my project I need to connect multiple (more than 2) I2S microphones to RPi 3. I see several different ways how to do that, on the other hand I'd like stay with minimum (or none) additional hardware.
My idea is to use standard existing I2S, just to add additional data-in ports on the GPIO. All I2S clocks would be shared over all I2S ports. Like that I'd read from GPIO instead of one bit, four or more bits (following number of I2S data-in ports I'd add). I had several discussions and I received fairly contradictory informations as on one side it was told to me that GPIO is not fast enough, on the other one of posts in this forum speaks about GPIO speed on the level of MHz. My target speed (bitclock) is of order 700kbps.
Can anybody advise me if the approach I proposed is feasible, e.g. that in principle the HW can manage it, and also point out (if exist) some software (drivers) that could help me to implement such a multiport I2S input.
Thanks to everybody