fix to hard code Can clock source to OSC

see: imxrt-rs#122 (comment)

Author: dstric-aqueduct

imxrt-hal/src/can/mod.rs

@@ -51,7 +51,7 @@ impl Unclocked {
         );
 
         let clk_sel = match clock_select {
-            ccm::can::ClockSelect::Pll2 => ral::ccm::CSCMR2::CAN_CLK_SEL::RW::CAN_CLK_SEL_1,
+            ccm::can::ClockSelect::OSC => ral::ccm::CSCMR2::CAN_CLK_SEL::RW::CAN_CLK_SEL_1,
         };
 
         // Select clock, and commit prescalar

imxrt-hal/src/ccm.rs

@@ -968,12 +968,12 @@ pub mod spi {
 
 /// Timing configurations for FlexCAN peripherals
 pub mod can {
-    use super::{ral::ccm, Divider, Frequency};
+    use super::{ral::ccm, Divider, Frequency, OSCILLATOR_FREQUENCY};
 
     #[derive(Clone, Copy)]
     #[non_exhaustive] // Not all variants added
     pub enum ClockSelect {
-        Pll2,
+        OSC,
     }
 
     #[derive(Clone, Copy, Debug, PartialEq, Eq)]
@@ -1113,7 +1113,7 @@ pub mod can {
     impl From<ClockSelect> for Frequency {
         fn from(clock_select: ClockSelect) -> Self {
             match clock_select {
-                ClockSelect::Pll2 => Frequency(528_000_000),
+                ClockSelect::OSC => OSCILLATOR_FREQUENCY,
             }
         }
     }