the trait bound ... is not satisfied

[fmckeogh]

Building any example that uses i2c on both nightly-2018-05-10 and nightly-2018-04-18 results in the following errors. I am not sure if it is issue with ssd1306, my apologies if it is with another crate.

error[E0277]: the trait bound `blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>: hal::prelude::Write` is not satisfied
  --> examples/graphics_i2c.rs:60:52
   |
60 |     let mut disp: GraphicsMode<_> = Builder::new().connect_i2c(i2c).into();
   |                                                    ^^^^^^^^^^^ the trait `hal::prelude::Write` is not implemented for `blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>`

error[E0277]: the trait bound `blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>: hal::prelude::Write` is not satisfied
  --> examples/graphics_i2c.rs:60:69
   |
60 |     let mut disp: GraphicsMode<_> = Builder::new().connect_i2c(i2c).into();
   |                                                                     ^^^^ the trait `hal::prelude::Write` is not implemented for `blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>`
   |
   = note: required because of the requirements on the impl of `ssd1306::interface::DisplayInterface` for `ssd1306::interface::I2cInterface<blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>>`

error[E0277]: the trait bound `blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>: hal::prelude::Write` is not satisfied
  --> examples/graphics_i2c.rs:60:19
   |
60 |     let mut disp: GraphicsMode<_> = Builder::new().connect_i2c(i2c).into();
   |                   ^^^^^^^^^^^^^^^ the trait `hal::prelude::Write` is not implemented for `blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>`
   |
   = note: required because of the requirements on the impl of `ssd1306::interface::DisplayInterface` for `ssd1306::interface::I2cInterface<blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>>`
   = note: required by `ssd1306::mode::GraphicsMode`

error[E0599]: no method named `init` found for type `ssd1306::mode::GraphicsMode<ssd1306::interface::I2cInterface<blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>>>` in the current scope
  --> examples/graphics_i2c.rs:62:10
   |
62 |     disp.init().unwrap();
   |          ^^^^
   |
   = note: the method `init` exists but the following trait bounds were not satisfied:
           `ssd1306::interface::I2cInterface<blue_pill::i2c::I2c<blue_pill::<unnamed>::I2C1, (blue_pill::gpio::gpiob::PB8<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>, blue_pill::gpio::gpiob::PB9<blue_pill::gpio::Alternate<blue_pill::gpio::OpenDrain>>)>> : ssd1306::interface::DisplayInterface`

[therealprof]

Hm, the interfaces have changed. Guess we'll need to wait until the dust settles around the latest breakage before attempting to fix everything.

[ilya-epifanov]

japaric/stm32f103xx-hal#50 (comment)

I2c no longer implements Write, Read and WriteRead. You should use BlockingI2c for this.