Switch RISC-V MSRV to nightly release channel (#725)

* Use `nightly` release for MSRV check

* Un-pin the `log` package version

.github/workflows/ci.yml

@@ -403,7 +403,8 @@ jobs:
       - uses: dtolnay/rust-toolchain@v1
         with:
           target: riscv32imc-unknown-none-elf, riscv32imac-unknown-none-elf
-          toolchain: "1.65.0"
+          toolchain: "nightly-2022-09-16"
+          components: rust-src
       - uses: Swatinem/rust-cache@v2
 
       # Verify the MSRV for all RISC-V chips.

README.md

@@ -90,7 +90,8 @@ There are a number of other crates within the [esp-rs organization] which can be
 
 The **M**inimum **S**upported **R**ust **V**ersions are:
 
-- `1.65.0` for RISC-V devices (**ESP32-C2**, **ESP32-C3**, **ESP32-C6**, **ESP32-H2**)
+- `nightly-2022-09-16` for RISC-V devices (**ESP32-C2**, **ESP32-C3**, **ESP32-C6**, **ESP32-H2**)
+  - This corresponds to the date that the `1.65.0` release was branched from `master`
 - `1.65.0` for Xtensa devices (**ESP32**, **ESP32-S2**, **ESP32-S3**)
 - `1.67.0` for all `async` examples (`embassy_hello_world`, `embassy_wait`, etc.)
 

esp-hal-common/Cargo.toml

@@ -23,7 +23,7 @@ embedded-hal-1       = { version = "=1.0.0-alpha.11", optional = true, package =
 embedded-hal-nb      = { version = "=1.0.0-alpha.3", optional = true }
 esp-synopsys-usb-otg = { version = "0.3.2", optional = true, features = ["fs", "esp32sx"] }
 fugit                = "0.3.7"
-log                  = "=0.4.18"
+log                  = "0.4.20"
 lock_api             = { version = "0.4.10", optional = true }
 nb                   = "1.1.0"
 paste                = "1.0.14"