Deprecate pwm implementation (#352)

Author: Sh3Rm4n

CHANGELOG.md

@@ -35,6 +35,13 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - Fix wrong timer frequency calculation and unexpected panics ([#338])
 
+### Changed
+
+- The PWM implementation was deprecated. There is not yet an alternative
+  implementation, but it is hard to maintain the current implementation
+  and not easy to verify if it is really a safe implementation.
+  It is also not consistent with the rest of the crates API. ([#352])
+
 ## [v0.9.2] - 2023-02-20
 
 ### Added
@@ -599,6 +606,7 @@ let clocks = rcc
 [defmt]: https://github.com/knurling-rs/defmt
 [filter]: https://defmt.ferrous-systems.com/filtering.html
 
+[#352]: https://github.com/stm32-rs/stm32f3xx-hal/pull/352
 [#345]: https://github.com/stm32-rs/stm32f3xx-hal/pull/345
 [#346]: https://github.com/stm32-rs/stm32f3xx-hal/pull/346
 [#347]: https://github.com/stm32-rs/stm32f3xx-hal/pull/347

examples/pwm.rs

@@ -17,6 +17,7 @@ use hal::flash::FlashExt;
 use hal::gpio::GpioExt;
 use hal::pac;
 use hal::prelude::*;
+#[allow(deprecated)]
 use hal::pwm::{tim16, tim2, tim3, tim8};
 use hal::rcc::RccExt;
 
@@ -70,6 +71,7 @@ fn main() -> ! {
     // TIM3
     //
     // A four channel general purpose timer that's broadly available
+    #[allow(deprecated)]
     let tim3_channels = tim3(
         dp.TIM3,
         1280,    // resolution of duty cycle
@@ -119,6 +121,7 @@ fn main() -> ! {
     // TIM2
     //
     // A 32-bit timer, so we can set a larger resolution
+    #[allow(deprecated)]
     let tim2_channels = tim2(
         dp.TIM2,
         160000,  // resolution of duty cycle
@@ -134,6 +137,7 @@ fn main() -> ! {
     //
     // A single channel timer, so it doesn't return a tuple.  We can
     // just use it directly
+    #[allow(deprecated)]
     let mut tim16_ch1 = tim16(
         dp.TIM16,
         1280,    // resolution of duty cycle
@@ -148,6 +152,7 @@ fn main() -> ! {
     //
     // An advanced timer with complementary outputs, so we can output
     // to complementary pins (works just like standard pins)
+    #[allow(deprecated)]
     let tim8_channels = tim8(
         dp.TIM8,
         1280,       // resolution of duty cycle

src/pwm.rs

@@ -282,6 +282,7 @@ macro_rules! pwm_timer_private {
         /// of exactly one degree.
         #[allow(unused_parens)]
         #[must_use]
+        #[deprecated(since = "0.10.0", note = "needs refactoring and might violate safety rules conflicting with the timer API")]
         pub fn $timx(tim: $TIMx, res: $res, freq: Hertz, clocks: &Clocks) -> ($(PwmChannel<$TIMx_CHy, NoPins>),+) {
             // Power the timer and reset it to ensure a clean state
             // We use unsafe here to abstract away this implementation detail