stm32: allow setting the PWM output polarity

embassy-stm32/src/timer/complementary_pwm.rs

@@ -108,6 +108,11 @@ impl<'d, T: ComplementaryCaptureCompare16bitInstance> ComplementaryPwm<'d, T> {
         self.inner.set_compare_value(channel, duty)
     }
 
+    pub fn set_polarity(&mut self, channel: Channel, polarity: OutputPolarity) {
+        self.inner.set_output_polarity(channel, polarity);
+        self.inner.set_complementary_output_polarity(channel, polarity);
+    }
+
     /// Set the dead time as a proportion of max_duty
     pub fn set_dead_time(&mut self, value: u16) {
         let (ckd, value) = compute_dead_time_value(value);

embassy-stm32/src/timer/mod.rs

@@ -53,6 +53,8 @@ pub(crate) mod sealed {
 
         fn set_output_compare_mode(&mut self, channel: Channel, mode: OutputCompareMode);
 
+        fn set_output_polarity(&mut self, channel: Channel, polarity: OutputPolarity);
+
         fn enable_channel(&mut self, channel: Channel, enable: bool);
 
         fn set_compare_value(&mut self, channel: Channel, value: u16);
@@ -61,6 +63,8 @@ pub(crate) mod sealed {
     }
 
     pub trait ComplementaryCaptureCompare16bitInstance: CaptureCompare16bitInstance {
+        fn set_complementary_output_polarity(&mut self, channel: Channel, polarity: OutputPolarity);
+
         fn set_dead_time_clock_division(&mut self, value: vals::Ckd);
 
         fn set_dead_time_value(&mut self, value: u8);
@@ -71,6 +75,8 @@ pub(crate) mod sealed {
     pub trait CaptureCompare32bitInstance: GeneralPurpose32bitInstance {
         fn set_output_compare_mode(&mut self, channel: Channel, mode: OutputCompareMode);
 
+        fn set_output_polarity(&mut self, channel: Channel, polarity: OutputPolarity);
+
         fn enable_channel(&mut self, channel: Channel, enable: bool);
 
         fn set_compare_value(&mut self, channel: Channel, value: u32);
@@ -125,6 +131,21 @@ impl From<OutputCompareMode> for stm32_metapac::timer::vals::Ocm {
     }
 }
 
+#[derive(Clone, Copy)]
+pub enum OutputPolarity {
+    ActiveHigh,
+    ActiveLow,
+}
+
+impl From<OutputPolarity> for bool {
+    fn from(mode: OutputPolarity) -> Self {
+        match mode {
+            OutputPolarity::ActiveHigh => false,
+            OutputPolarity::ActiveLow => true,
+        }
+    }
+}
+
 pub trait Basic16bitInstance: sealed::Basic16bitInstance + 'static {}
 
 pub trait GeneralPurpose16bitInstance: sealed::GeneralPurpose16bitInstance + 'static {}
@@ -265,6 +286,13 @@ macro_rules! impl_compare_capable_16bit {
                     .modify(|w| w.set_ocm(raw_channel % 2, mode.into()));
             }
 
+            fn set_output_polarity(&mut self, channel: Channel, polarity: OutputPolarity) {
+                use sealed::GeneralPurpose16bitInstance;
+                Self::regs_gp16()
+                    .ccer()
+                    .modify(|w| w.set_ccp(channel.raw(), polarity.into()));
+            }
+
             fn enable_channel(&mut self, channel: Channel, enable: bool) {
                 use sealed::GeneralPurpose16bitInstance;
                 Self::regs_gp16()
@@ -325,6 +353,13 @@ foreach_interrupt! {
                 Self::regs_gp32().ccmr_output(raw_channel / 2).modify(|w| w.set_ocm(raw_channel % 2, mode.into()));
             }
 
+            fn set_output_polarity(&mut self, channel: Channel, polarity: OutputPolarity) {
+                use crate::timer::sealed::GeneralPurpose32bitInstance;
+                Self::regs_gp32()
+                    .ccer()
+                    .modify(|w| w.set_ccp(channel.raw(), polarity.into()));
+            }
+
             fn enable_channel(&mut self, channel: Channel, enable: bool) {
                 use crate::timer::sealed::GeneralPurpose32bitInstance;
                 Self::regs_gp32().ccer().modify(|w| w.set_cce(channel.raw(), enable));
@@ -388,6 +423,13 @@ foreach_interrupt! {
                     .modify(|w| w.set_ocm(raw_channel % 2, mode.into()));
             }
 
+            fn set_output_polarity(&mut self, channel: Channel, polarity: OutputPolarity) {
+                use crate::timer::sealed::AdvancedControlInstance;
+                Self::regs_advanced()
+                    .ccer()
+                    .modify(|w| w.set_ccp(channel.raw(), polarity.into()));
+            }
+
             fn enable_channel(&mut self, channel: Channel, enable: bool) {
                 use crate::timer::sealed::AdvancedControlInstance;
                 Self::regs_advanced()
@@ -409,6 +451,13 @@ foreach_interrupt! {
         }
 
         impl sealed::ComplementaryCaptureCompare16bitInstance for crate::peripherals::$inst {
+            fn set_complementary_output_polarity(&mut self, channel: Channel, polarity: OutputPolarity) {
+                use crate::timer::sealed::AdvancedControlInstance;
+                Self::regs_advanced()
+                    .ccer()
+                    .modify(|w| w.set_ccnp(channel.raw(), polarity.into()));
+            }
+
             fn set_dead_time_clock_division(&mut self, value: vals::Ckd) {
                 use crate::timer::sealed::AdvancedControlInstance;
                 Self::regs_advanced().cr1().modify(|w| w.set_ckd(value));

embassy-stm32/src/timer/simple_pwm.rs

@@ -104,4 +104,8 @@ impl<'d, T: CaptureCompare16bitInstance> SimplePwm<'d, T> {
         assert!(duty <= self.get_max_duty());
         self.inner.set_compare_value(channel, duty)
     }
+
+    pub fn set_polarity(&mut self, channel: Channel, polarity: OutputPolarity) {
+        self.inner.set_output_polarity(channel, polarity);
+    }
 }