I2C timeout issues on ESP32 and ESP32S3

[yanshay]

I'm trying to use I2C with a PN532 board.

On ESP32 I managed to get it to work, however not without issues:

1. When created ### the I2C w/o timeout, I always received timeout errors, which doesn't sound right, I'd expect it to hang if there was a timeout, no? Maybe w/o timeout it defaults to timeout of 0?
2. When I created the I2C with timeout it mostly worked (so the device didn't really timeout). I used a very high timeout number, while later learnt that shouldn't work as from the code it looked like the number is limited to 8 bits value, but not verified in the code.

On ESP32S3

1. w/o timeout, the write hanged (could be something wrong with my wiring, but that's not the issue), so I tried using the timeout. First it panicked, then I learnt that I've set the timeout value too large (it's u32 in the interface but seems to be converted to u8 in the code), and the hal code on the non-ESP32 does such conversion (unlike the ESP32 code).
2. So I reduced the timeout to be within the range of the bits (which I believe is 8 bits), and it still hangs, timeout never takes place.

Looking at the i2c.rs code I found the code below, where it says that it requires a fix.
But the code looks like it's written. So is timeout on non ESP32 (in my case ESP32S3) working or not?
Also, in the ESP32 the time_out_value is not converted to u8 before feeding into the register (and it's a u32), is that correct behavior?

BTW, if it matters on the ESP32 I use I2C0 and on ESP32S3 I use I2C1.

            // The ESP32 variant does not have an enable flag for the
            // timeout mechanism
            cfg_if::cfg_if! {
                if #[cfg(esp32)] {
                    // timeout
                    self.register_block()
                        .to()
                        .write(|w| w.time_out().bits(time_out_value));    <--------- value fed as is
                }
                else {
                    // timeout
                    // FIXME: Enable timout for other chips!      <----------------- need to fix anything here?
                    #[allow(clippy::useless_conversion)]
                    self.register_block()
                        .to()
                        .write(|w| w.time_out_en().bit(time_out_en)
                        .time_out_value()
                        .bits(time_out_value.try_into().unwrap()).     <---------- panic if value too large
                    );
                }
            }

[lure23]

I'm also experiencing this (there's an issue open since 2 days: #2026).

• Can help test on C3 (ESP32-C3-DevKitC-02)
• Does not happen on C6 (ESP32-C6-DevKitM-1)

Since this is discussion, would you like to create an Issue with the above text, or join the existing one? :)

[MabezDev]

Please try again on main.

For future reference, bug reports should be opened as issues as I completely missed this till now.