channels: Refactor set_pwm to take voltage

The duty cycle of PWM pins can then be abstracted from its users.

src/channels.rs

@@ -398,14 +398,21 @@ impl Channels {
             * 4.0
     }
 
-    fn set_pwm(&mut self, channel: usize, pin: PwmPin, duty: f64) -> f64 {
+    fn set_pwm_pin_voltage(
+        &mut self,
+        channel: usize,
+        pin: PwmPin,
+        voltage: ElectricPotential,
+    ) -> ElectricPotential {
         fn set<P: hal::PwmPin<Duty = u16>>(pin: &mut P, duty: f64) -> f64 {
             let max = pin.get_max_duty();
             let value = ((duty * (max as f64)) as u16).min(max);
             pin.set_duty(value);
             value as f64 / (max as f64)
         }
-        match (channel, pin) {
+        let duty: f64 = (voltage / CPU_ADC_VREF).into();
+
+        let duty = match (channel, pin) {
             (_, PwmPin::ISet) => panic!("i_set is no pwm pin"),
             (0, PwmPin::MaxIPos) => set(&mut self.pwm.max_i_pos0, duty),
             (0, PwmPin::MaxINeg) => set(&mut self.pwm.max_i_neg0, duty),
@@ -414,7 +421,8 @@ impl Channels {
             (1, PwmPin::MaxINeg) => set(&mut self.pwm.max_i_neg1, duty),
             (1, PwmPin::MaxV) => set(&mut self.pwm.max_v1, duty),
             _ => unreachable!(),
-        }
+        };
+        duty * CPU_ADC_VREF
     }
 
     pub fn set_max_v(
@@ -425,10 +433,8 @@ impl Channels {
         let max_v = max_v.min(MAX_TEC_V).max(ElectricPotential::zero());
         self.channel_state(channel).output_limits.max_v = max_v;
         let v_maxv = max_v / 4.0;
-        let duty = (v_maxv / CPU_ADC_VREF).get::<ratio>();
 
-        let duty = self.set_pwm(channel, PwmPin::MaxV, duty);
-        let v_maxv = duty * CPU_ADC_VREF;
+        let v_maxv = self.set_pwm_pin_voltage(channel, PwmPin::MaxV, v_maxv);
         let max_v = 4.0 * v_maxv;
 
         (max_v, MAX_TEC_V)
@@ -448,10 +454,8 @@ impl Channels {
         let max_i_pos = max_i_pos.min(MAX_TEC_I).max(ElectricCurrent::zero());
         self.channel_state(channel).output_limits.max_i_pos = max_i_pos;
         let v_maxip = 10.0 * (max_i_pos * r_sense);
-        let duty = (v_maxip / CPU_ADC_VREF).get::<ratio>();
 
-        let duty = self.set_pwm(channel, pin, duty);
-        let v_maxip = duty * CPU_ADC_VREF;
+        let v_maxip = self.set_pwm_pin_voltage(channel, pin, v_maxip);
         let max_i_pos = v_maxip / 10.0 / r_sense;
 
         (max_i_pos, MAX_TEC_I)
@@ -471,10 +475,8 @@ impl Channels {
         let max_i_neg = max_i_neg.min(MAX_TEC_I).max(ElectricCurrent::zero());
         self.channel_state(channel).output_limits.max_i_neg = max_i_neg;
         let v_maxin = 10.0 * (max_i_neg * r_sense);
-        let duty = (v_maxin / CPU_ADC_VREF).get::<ratio>();
 
-        let duty = self.set_pwm(channel, pin, duty);
-        let v_maxin = duty * CPU_ADC_VREF;
+        let v_maxin = self.set_pwm_pin_voltage(channel, pin, v_maxin);
         let max_i_neg = v_maxin / 10.0 / r_sense;
 
         (max_i_neg, MAX_TEC_I)