[iMXRT] dma: define MAX_CHUNK_SIZE constant

Instead of adding magic constants all over the place, let's just
define DMA MAX_CHUNK_SIZE in a single constant that be referenced by
the various users.

2 files changed, 4 insertions, 2 deletions

diff --git a/embassy-imxrt/src/dma.rs b/embassy-imxrt/src/dma.rs
index e71a27e0e..76c9953c1 100644
--- a/embassy-imxrt/src/dma.rs
+++ b/embassy-imxrt/src/dma.rs
@@ -16,6 +16,8 @@ use crate::peripherals::DMA0;
 use crate::sealed::Sealed;
 use crate::{BitIter, interrupt, pac, peripherals};
 
+pub(crate) const MAX_CHUNK_SIZE: usize = 1024;
+
 #[cfg(feature = "rt")]
 #[interrupt]
 fn DMA0() {
diff --git a/embassy-imxrt/src/flexcomm/uart.rs b/embassy-imxrt/src/flexcomm/uart.rs
index 2b759ba84..d13b32e93 100644
--- a/embassy-imxrt/src/flexcomm/uart.rs
+++ b/embassy-imxrt/src/flexcomm/uart.rs
@@ -598,7 +598,7 @@ impl<'a> UartTx<'a, Async> {
             regs.fifocfg().modify(|_, w| w.dmatx().disabled());
         });
 
-        for chunk in buf.chunks(1024) {
+        for chunk in buf.chunks(dma::MAX_CHUNK_SIZE) {
             regs.fifocfg().modify(|_, w| w.dmatx().enabled());
 
             let ch = self.tx_dma.as_mut().unwrap().reborrow();
@@ -726,7 +726,7 @@ impl<'a> UartRx<'a, Async> {
             regs.fifocfg().modify(|_, w| w.dmarx().disabled());
         });
 
-        for chunk in buf.chunks_mut(1024) {
+        for chunk in buf.chunks_mut(dma::MAX_CHUNK_SIZE) {
             regs.fifocfg().modify(|_, w| w.dmarx().enabled());
 
             let ch = self.rx_dma.as_mut().unwrap().reborrow();