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i2c-v2: Correct number of chunks calculation

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This commit is contained in:
Thales Fragoso
2021-07-08 19:53:47 -03:00
parent 8c7f8a61e3
commit f2e78e9c34
2 changed files with 21 additions and 6 deletions
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1
embassy-stm32/src/i2c/mod.rs
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@@ -6,6 +6,7 @@ mod _version;
use crate::peripherals;
pub use _version::*;
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum Error {
Bus,
Arbitration,

26
embassy-stm32/src/i2c/v2.rs
View File

@@ -147,6 +147,8 @@ impl<'d, T: Instance> I2c<'d, T> {
fn master_continue(&mut self, length: usize, reload: bool) {
assert!(length < 256 && length > 0);
while unsafe { !T::regs().isr().read().tcr() } {}
let reload = if reload {
i2c::vals::Reload::NOTCOMPLETED
} else {
@@ -245,19 +247,25 @@ impl<'d, T: Instance> I2c<'d, T> {
}
fn read(&mut self, address: u8, buffer: &mut [u8], restart: bool) -> Result<(), Error> {
let last_chunk = (buffer.len() / 255).saturating_sub(1);
let completed_chunks = buffer.len() / 255;
let total_chunks = if completed_chunks * 255 == buffer.len() {
completed_chunks
} else {
completed_chunks + 1
};
let last_chunk_idx = total_chunks.saturating_sub(1);
self.master_read(
address,
buffer.len().min(255),
Stop::Automatic,
last_chunk != 0,
last_chunk_idx != 0,
restart,
);
for (number, chunk) in buffer.chunks_mut(255).enumerate() {
if number != 0 {
self.master_continue(chunk.len(), number != last_chunk);
self.master_continue(chunk.len(), number != last_chunk_idx);
}
for byte in chunk {
@@ -273,7 +281,13 @@ impl<'d, T: Instance> I2c<'d, T> {
}
fn write(&mut self, address: u8, bytes: &[u8], send_stop: bool) -> Result<(), Error> {
let last_chunk = (bytes.len() / 255).saturating_sub(1);
let completed_chunks = bytes.len() / 255;
let total_chunks = if completed_chunks * 255 == bytes.len() {
completed_chunks
} else {
completed_chunks + 1
};
let last_chunk_idx = total_chunks.saturating_sub(1);
// I2C start
//
@@ -282,12 +296,12 @@ impl<'d, T: Instance> I2c<'d, T> {
address,
bytes.len().min(255),
Stop::Software,
last_chunk != 0,
last_chunk_idx != 0,
);
for (number, chunk) in bytes.chunks(255).enumerate() {
if number != 0 {
self.master_continue(chunk.len(), number != last_chunk);
self.master_continue(chunk.len(), number != last_chunk_idx);
}
for byte in chunk {