748 lines
23 KiB
Rust

//! USB Type-C/USB Power Delivery Interface (UCPD)
// Implementation Notes
//
// As of Feb. 2024 the UCPD peripheral is availalbe on: G0, G4, H5, L5, U5
//
// Cube HAL LL Driver (g0):
// https://github.com/STMicroelectronics/stm32g0xx_hal_driver/blob/v1.4.6/Inc/stm32g0xx_ll_ucpd.h
// https://github.com/STMicroelectronics/stm32g0xx_hal_driver/blob/v1.4.6/Src/stm32g0xx_ll_ucpd.c
// Except for a the `LL_UCPD_RxAnalogFilterEnable/Disable()` functions the Cube HAL implementation of
// all families is the same.
//
// Dead battery pull-down resistors functionality is enabled by default on startup and must
// be disabled by setting a bit in PWR/SYSCFG registers. The exact name and location for that
// bit is different for each familily.
use core::future::poll_fn;
use core::marker::PhantomData;
use core::sync::atomic::{AtomicBool, Ordering};
use core::task::Poll;
use embassy_hal_internal::drop::OnDrop;
use embassy_hal_internal::PeripheralType;
use embassy_sync::waitqueue::AtomicWaker;
use crate::dma::{ChannelAndRequest, TransferOptions};
use crate::interrupt::typelevel::Interrupt;
use crate::pac::ucpd::vals::{Anamode, Ccenable, PscUsbpdclk, Txmode};
pub use crate::pac::ucpd::vals::{Phyccsel as CcSel, Rxordset, TypecVstateCc as CcVState};
use crate::rcc::{self, RccPeripheral};
use crate::{interrupt, Peri};
pub(crate) fn init(
_cs: critical_section::CriticalSection,
#[cfg(peri_ucpd1)] ucpd1_db_enable: bool,
#[cfg(peri_ucpd2)] ucpd2_db_enable: bool,
) {
#[cfg(stm32g0x1)]
{
// according to RM0444 (STM32G0x1) section 8.1.1:
// when UCPD is disabled setting the strobe will disable dead battery
// (which is enabled after reset) but if UCPD is enabled, setting the
// strobe will apply the CC pin configuration from the control register
// (which is why we need to be careful about when we call this)
crate::pac::SYSCFG.cfgr1().modify(|w| {
w.set_ucpd1_strobe(!ucpd1_db_enable);
w.set_ucpd2_strobe(!ucpd2_db_enable);
});
}
#[cfg(any(stm32g4, stm32l5))]
{
crate::pac::PWR.cr3().modify(|w| {
#[cfg(stm32g4)]
w.set_ucpd1_dbdis(!ucpd1_db_enable);
#[cfg(stm32l5)]
w.set_ucpd_dbdis(!ucpd1_db_enable);
})
}
#[cfg(any(stm32h5, stm32u5, stm32h7rs))]
{
crate::pac::PWR.ucpdr().modify(|w| {
w.set_ucpd_dbdis(!ucpd1_db_enable);
})
}
}
/// Pull-up or Pull-down resistor state of both CC lines.
#[derive(Debug, Clone, Copy, PartialEq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum CcPull {
/// Analog PHY for CC pin disabled.
Disabled,
/// Rd=5.1k pull-down resistor.
Sink,
/// Rp=56k pull-up resistor to indicate default USB power.
SourceDefaultUsb,
/// Rp=22k pull-up resistor to indicate support for up to 1.5A.
Source1_5A,
/// Rp=10k pull-up resistor to indicate support for up to 3.0A.
Source3_0A,
}
/// UCPD configuration
#[non_exhaustive]
#[derive(Copy, Clone, Debug)]
pub struct Config {
/// Receive SOP packets
pub sop: bool,
/// Receive SOP' packets
pub sop_prime: bool,
/// Receive SOP'' packets
pub sop_double_prime: bool,
/// Receive SOP'_Debug packets
pub sop_prime_debug: bool,
/// Receive SOP''_Debug packets
pub sop_double_prime_debug: bool,
}
impl Default for Config {
fn default() -> Self {
Self {
sop: true,
sop_prime: false,
sop_double_prime: false,
sop_prime_debug: false,
sop_double_prime_debug: false,
}
}
}
/// UCPD driver.
pub struct Ucpd<'d, T: Instance> {
cc_phy: CcPhy<'d, T>,
}
impl<'d, T: Instance> Ucpd<'d, T> {
/// Creates a new UCPD driver instance.
pub fn new(
_peri: Peri<'d, T>,
_irq: impl interrupt::typelevel::Binding<T::Interrupt, InterruptHandler<T>> + 'd,
cc1: Peri<'d, impl Cc1Pin<T>>,
cc2: Peri<'d, impl Cc2Pin<T>>,
config: Config,
) -> Self {
cc1.set_as_analog();
cc2.set_as_analog();
rcc::enable_and_reset::<T>();
T::Interrupt::unpend();
unsafe { T::Interrupt::enable() };
let r = T::REGS;
#[cfg(stm32h5)]
r.cfgr2().write(|w| {
// Only takes effect, when UCPDEN=0.
w.set_rxafilten(true);
});
r.cfgr1().write(|w| {
// "The receiver is designed to work in the clock frequency range from 6 to 18 MHz.
// However, the optimum performance is ensured in the range from 6 to 12 MHz"
// UCPD is driven by HSI16 (16MHz internal oscillator), which we need to divide by 2.
w.set_psc_usbpdclk(PscUsbpdclk::DIV2);
// Prescaler to produce a target half-bit frequency of 600kHz which is required
// to produce transmit with a nominal nominal bit rate of 300Kbps+-10% using
// biphase mark coding (BMC, aka differential manchester coding).
// A divider of 13 gives the target frequency closest to spec (~615kHz, 1.625us).
w.set_hbitclkdiv(13 - 1);
// Time window for detecting non-idle (12-20us).
// 1.75us * 8 = 14us.
w.set_transwin(8 - 1);
// Time from the end of last bit of a Frame until the start of the first bit of the
// next Preamble (min 25us).
// 1.75us * 17 = ~30us
w.set_ifrgap(17 - 1);
// UNDOCUMENTED: This register can only be written while UCPDEN=0 (found by testing).
let rxordset = (config.sop as u16) << 0
| (config.sop_prime as u16) << 1
| (config.sop_double_prime as u16) << 2
// Hard reset
| 0x1 << 3
| (config.sop_prime_debug as u16) << 4
| (config.sop_double_prime_debug as u16) << 5;
w.set_rxordseten(rxordset);
// Enable DMA
w.set_txdmaen(true);
w.set_rxdmaen(true);
w.set_ucpden(true);
});
// Software trim according to RM0481, p. 2650/2668
#[cfg(stm32h5)]
{
let trim_rd_cc1 = unsafe { *(0x4002_242C as *const u32) & 0xF };
let trim_rd_cc2 = unsafe { ((*(0x4002_242C as *const u32)) >> 8) & 0xF };
r.cfgr3().write(|w| {
w.set_trim_cc1_rd(trim_rd_cc1 as u8);
w.set_trim_cc2_rd(trim_rd_cc2 as u8);
});
}
// Software trim according to RM0456, p. 3480/3462
#[cfg(stm32u5)]
{
let trim_rd_cc1 = unsafe { *(0x0BFA_0544 as *const u8) & 0xF };
let trim_rd_cc2 = unsafe { *(0x0BFA_0546 as *const u8) & 0xF };
r.cfgr3().write(|w| {
w.set_trim_cc1_rd(trim_rd_cc1);
w.set_trim_cc2_rd(trim_rd_cc2);
});
}
Self {
cc_phy: CcPhy { _lifetime: PhantomData },
}
}
/// Returns the TypeC CC PHY.
pub fn cc_phy(&mut self) -> &mut CcPhy<'d, T> {
&mut self.cc_phy
}
/// Splits the UCPD driver into a TypeC PHY to control and monitor CC voltage
/// and a Power Delivery (PD) PHY with receiver and transmitter.
pub fn split_pd_phy(
self,
rx_dma: Peri<'d, impl RxDma<T>>,
tx_dma: Peri<'d, impl TxDma<T>>,
cc_sel: CcSel,
) -> (CcPhy<'d, T>, PdPhy<'d, T>) {
let r = T::REGS;
// TODO: Currently only SOP messages are supported.
r.tx_ordsetr().write(|w| w.set_txordset(0b10001_11000_11000_11000));
// Enable the receiver on one of the two CC lines.
r.cr().modify(|w| w.set_phyccsel(cc_sel));
// Enable hard reset receive interrupt.
r.imr().modify(|w| w.set_rxhrstdetie(true));
// Enable PD packet reception
r.cr().modify(|w| w.set_phyrxen(true));
// Both parts must be dropped before the peripheral can be disabled.
T::state().drop_not_ready.store(true, Ordering::Relaxed);
let rx_dma_req = rx_dma.request();
let tx_dma_req = tx_dma.request();
(
self.cc_phy,
PdPhy {
_lifetime: PhantomData,
rx_dma: ChannelAndRequest {
channel: rx_dma.into(),
request: rx_dma_req,
},
tx_dma: ChannelAndRequest {
channel: tx_dma.into(),
request: tx_dma_req,
},
},
)
}
}
/// Control and monitoring of TypeC CC pin functionailty.
pub struct CcPhy<'d, T: Instance> {
_lifetime: PhantomData<&'d mut T>,
}
impl<'d, T: Instance> Drop for CcPhy<'d, T> {
fn drop(&mut self) {
let r = T::REGS;
r.cr().modify(|w| {
w.set_cc1tcdis(true);
w.set_cc2tcdis(true);
w.set_ccenable(Ccenable::DISABLED);
});
// Check if the PdPhy part was dropped already.
let drop_not_ready = &T::state().drop_not_ready;
if drop_not_ready.load(Ordering::Relaxed) {
drop_not_ready.store(false, Ordering::Relaxed);
} else {
r.cfgr1().write(|w| w.set_ucpden(false));
rcc::disable::<T>();
T::Interrupt::disable();
}
}
}
impl<'d, T: Instance> CcPhy<'d, T> {
/// Sets the pull-up/pull-down resistor values exposed on the CC pins.
pub fn set_pull(&mut self, cc_pull: CcPull) {
T::REGS.cr().modify(|w| {
w.set_anamode(if cc_pull == CcPull::Sink {
Anamode::SINK
} else {
Anamode::SOURCE
});
w.set_anasubmode(match cc_pull {
CcPull::SourceDefaultUsb => 1,
CcPull::Source1_5A => 2,
CcPull::Source3_0A => 3,
_ => 0,
});
w.set_ccenable(if cc_pull == CcPull::Disabled {
Ccenable::DISABLED
} else {
Ccenable::BOTH
});
});
// Software trim according to RM0481, p. 2650/2668
#[cfg(stm32h5)]
T::REGS.cfgr3().modify(|w| match cc_pull {
CcPull::Source1_5A => {
let trim_1a5_cc1 = unsafe { *(0x08FF_F844 as *const u32) & 0xF };
let trim_1a5_cc2 = unsafe { ((*(0x08FF_F844 as *const u32)) >> 16) & 0xF };
w.set_trim_cc1_rp(trim_1a5_cc1 as u8);
w.set_trim_cc2_rp(trim_1a5_cc2 as u8);
}
_ => {
let trim_3a0_cc1 = unsafe { (*(0x4002_242C as *const u32) >> 4) & 0xF };
let trim_3a0_cc2 = unsafe { ((*(0x4002_242C as *const u32)) >> 12) & 0xF };
w.set_trim_cc1_rp(trim_3a0_cc1 as u8);
w.set_trim_cc2_rp(trim_3a0_cc2 as u8);
}
});
// Software trim according to RM0456, p. 3480/3462
#[cfg(stm32u5)]
T::REGS.cfgr3().modify(|w| match cc_pull {
CcPull::Source1_5A => {
let trim_1a5_cc1 = unsafe { *(0x0BFA_07A7 as *const u8) & 0xF };
let trim_1a5_cc2 = unsafe { *(0x0BFA_07A8 as *const u8) & 0xF };
w.set_trim_cc1_rp(trim_1a5_cc1);
w.set_trim_cc2_rp(trim_1a5_cc2);
}
_ => {
let trim_3a0_cc1 = unsafe { *(0x0BFA_0545 as *const u8) & 0xF };
let trim_3a0_cc2 = unsafe { *(0x0BFA_0547 as *const u8) & 0xF };
w.set_trim_cc1_rp(trim_3a0_cc1);
w.set_trim_cc2_rp(trim_3a0_cc2);
}
});
// Disable dead-battery pull-down resistors which are enabled by default on boot.
critical_section::with(|cs| {
init(
cs,
false,
#[cfg(peri_ucpd2)]
false,
);
});
}
/// Returns the current voltage level of CC1 and CC2 pin as tuple.
///
/// Interpretation of the voltage levels depends on the configured CC line
/// pull-up/pull-down resistance.
pub fn vstate(&self) -> (CcVState, CcVState) {
let sr = T::REGS.sr().read();
(sr.typec_vstate_cc1(), sr.typec_vstate_cc2())
}
/// Waits for a change in voltage state on either CC line.
pub async fn wait_for_vstate_change(&self) -> (CcVState, CcVState) {
let _on_drop = OnDrop::new(|| self.enable_cc_interrupts(false));
let prev_vstate = self.vstate();
poll_fn(|cx| {
let vstate = self.vstate();
if vstate != prev_vstate {
Poll::Ready(vstate)
} else {
T::state().waker.register(cx.waker());
self.enable_cc_interrupts(true);
Poll::Pending
}
})
.await
}
fn enable_cc_interrupts(&self, enable: bool) {
T::REGS.imr().modify(|w| {
w.set_typecevt1ie(enable);
w.set_typecevt2ie(enable);
});
}
}
/// Receive SOP.
#[derive(Debug, Clone, Copy)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum Sop {
/// SOP
Sop,
/// SOP'
SopPrime,
/// SOP''
SopDoublePrime,
/// SOP'_Debug
SopPrimeDebug,
/// SOP''_Debug
SopDoublePrimeDebug,
}
/// Receive Error.
#[derive(Debug, Clone, Copy)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum RxError {
/// Incorrect CRC or truncated message (a line becoming static before EOP is met).
Crc,
/// Provided buffer was too small for the received message.
Overrun,
/// Hard Reset received before or during reception.
HardReset,
}
/// Transmit Error.
#[derive(Debug, Clone, Copy)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum TxError {
/// Concurrent receive in progress or excessive noise on the line.
Discarded,
/// Hard Reset received before or during transmission.
HardReset,
}
/// Power Delivery (PD) PHY.
pub struct PdPhy<'d, T: Instance> {
_lifetime: PhantomData<&'d mut T>,
rx_dma: ChannelAndRequest<'d>,
tx_dma: ChannelAndRequest<'d>,
}
impl<'d, T: Instance> Drop for PdPhy<'d, T> {
fn drop(&mut self) {
let r = T::REGS;
r.cr().modify(|w| w.set_phyrxen(false));
// Check if the CcPhy part was dropped already.
let drop_not_ready = &T::state().drop_not_ready;
if drop_not_ready.load(Ordering::Relaxed) {
drop_not_ready.store(false, Ordering::Relaxed);
} else {
r.cfgr1().write(|w| w.set_ucpden(false));
rcc::disable::<T>();
T::Interrupt::disable();
}
}
}
impl<'d, T: Instance> PdPhy<'d, T> {
/// Receives a PD message into the provided buffer.
///
/// Returns the number of received bytes or an error.
pub async fn receive(&mut self, buf: &mut [u8]) -> Result<usize, RxError> {
self.receive_with_sop(buf).await.map(|(_sop, size)| size)
}
/// Receives SOP and a PD message into the provided buffer.
///
/// Returns the start of packet type and number of received bytes or an error.
pub async fn receive_with_sop(&mut self, buf: &mut [u8]) -> Result<(Sop, usize), RxError> {
let r = T::REGS;
let mut dma = unsafe {
self.rx_dma
.read(r.rxdr().as_ptr() as *mut u8, buf, TransferOptions::default())
};
let _on_drop = OnDrop::new(|| {
Self::enable_rx_interrupt(false);
// Clear interrupt flags
r.icr().write(|w| {
w.set_rxorddetcf(true);
w.set_rxovrcf(true);
w.set_rxmsgendcf(true);
});
});
let mut rxpaysz = 0;
// Stop DMA reception immediately after receiving a packet, to prevent storing multiple packets in the same buffer.
poll_fn(|cx| {
let sr = r.sr().read();
if sr.rxhrstdet() {
dma.request_stop();
// Clean and re-enable hard reset receive interrupt.
r.icr().write(|w| w.set_rxhrstdetcf(true));
r.imr().modify(|w| w.set_rxhrstdetie(true));
Poll::Ready(Err(RxError::HardReset))
} else if sr.rxmsgend() {
dma.request_stop();
// Should be read immediately on interrupt.
rxpaysz = r.rx_payszr().read().rxpaysz().into();
let ret = if sr.rxovr() {
Err(RxError::Overrun)
} else if sr.rxerr() {
Err(RxError::Crc)
} else {
Ok(())
};
Poll::Ready(ret)
} else {
T::state().waker.register(cx.waker());
Self::enable_rx_interrupt(true);
Poll::Pending
}
})
.await?;
// Make sure that the last byte was fetched by DMA.
while r.sr().read().rxne() {
if dma.get_remaining_transfers() == 0 {
return Err(RxError::Overrun);
}
}
let sop = match r.rx_ordsetr().read().rxordset() {
Rxordset::SOP => Sop::Sop,
Rxordset::SOP_PRIME => Sop::SopPrime,
Rxordset::SOP_DOUBLE_PRIME => Sop::SopDoublePrime,
Rxordset::SOP_PRIME_DEBUG => Sop::SopPrimeDebug,
Rxordset::SOP_DOUBLE_PRIME_DEBUG => Sop::SopDoublePrimeDebug,
Rxordset::CABLE_RESET => return Err(RxError::HardReset),
// Extension headers are not supported
_ => unreachable!(),
};
Ok((sop, rxpaysz))
}
fn enable_rx_interrupt(enable: bool) {
T::REGS.imr().modify(|w| w.set_rxmsgendie(enable));
}
/// Transmits a PD message.
pub async fn transmit(&mut self, buf: &[u8]) -> Result<(), TxError> {
let r = T::REGS;
// When a previous transmission was dropped before it had finished it
// might still be running because there is no way to abort an ongoing
// message transmission. Wait for it to finish but ignore errors.
if r.cr().read().txsend() {
if let Err(TxError::HardReset) = Self::wait_tx_done().await {
return Err(TxError::HardReset);
}
}
// Clear the TX interrupt flags.
T::REGS.icr().write(|w| {
w.set_txmsgdisccf(true);
w.set_txmsgsentcf(true);
});
// Start the DMA and let it do its thing in the background.
let _dma = unsafe {
self.tx_dma
.write(buf, r.txdr().as_ptr() as *mut u8, TransferOptions::default())
};
// Configure and start the transmission.
r.tx_payszr().write(|w| w.set_txpaysz(buf.len() as _));
r.cr().modify(|w| {
w.set_txmode(Txmode::PACKET);
w.set_txsend(true);
});
Self::wait_tx_done().await
}
async fn wait_tx_done() -> Result<(), TxError> {
let _on_drop = OnDrop::new(|| Self::enable_tx_interrupts(false));
poll_fn(|cx| {
let r = T::REGS;
let sr = r.sr().read();
if sr.rxhrstdet() {
// Clean and re-enable hard reset receive interrupt.
r.icr().write(|w| w.set_rxhrstdetcf(true));
r.imr().modify(|w| w.set_rxhrstdetie(true));
Poll::Ready(Err(TxError::HardReset))
} else if sr.txmsgdisc() {
Poll::Ready(Err(TxError::Discarded))
} else if sr.txmsgsent() {
Poll::Ready(Ok(()))
} else {
T::state().waker.register(cx.waker());
Self::enable_tx_interrupts(true);
Poll::Pending
}
})
.await
}
fn enable_tx_interrupts(enable: bool) {
T::REGS.imr().modify(|w| {
w.set_txmsgdiscie(enable);
w.set_txmsgsentie(enable);
});
}
/// Transmit a hard reset.
pub async fn transmit_hardreset(&mut self) -> Result<(), TxError> {
let r = T::REGS;
// Clear the hardreset interrupt flags.
T::REGS.icr().write(|w| {
w.set_hrstdisccf(true);
w.set_hrstsentcf(true);
});
// Trigger hard reset transmission.
r.cr().modify(|w| {
w.set_txhrst(true);
});
let _on_drop = OnDrop::new(|| self.enable_hardreset_interrupts(false));
poll_fn(|cx| {
let r = T::REGS;
let sr = r.sr().read();
if sr.rxhrstdet() {
// Clean and re-enable hard reset receive interrupt.
r.icr().write(|w| w.set_rxhrstdetcf(true));
r.imr().modify(|w| w.set_rxhrstdetie(true));
Poll::Ready(Err(TxError::HardReset))
} else if sr.hrstdisc() {
Poll::Ready(Err(TxError::Discarded))
} else if sr.hrstsent() {
Poll::Ready(Ok(()))
} else {
T::state().waker.register(cx.waker());
self.enable_hardreset_interrupts(true);
Poll::Pending
}
})
.await
}
fn enable_hardreset_interrupts(&self, enable: bool) {
T::REGS.imr().modify(|w| {
w.set_hrstdiscie(enable);
w.set_hrstsentie(enable);
});
}
}
/// Interrupt handler.
pub struct InterruptHandler<T: Instance> {
_phantom: PhantomData<T>,
}
impl<T: Instance> interrupt::typelevel::Handler<T::Interrupt> for InterruptHandler<T> {
unsafe fn on_interrupt() {
let r = T::REGS;
let sr = r.sr().read();
if sr.typecevt1() || sr.typecevt2() {
r.icr().write(|w| {
w.set_typecevt1cf(true);
w.set_typecevt2cf(true);
});
}
if sr.rxhrstdet() {
r.imr().modify(|w| w.set_rxhrstdetie(false));
}
if sr.rxmsgend() {
r.imr().modify(|w| w.set_rxmsgendie(false));
}
if sr.txmsgdisc() || sr.txmsgsent() {
r.imr().modify(|w| {
w.set_txmsgdiscie(false);
w.set_txmsgsentie(false);
});
}
if sr.hrstdisc() || sr.hrstsent() {
r.imr().modify(|w| {
w.set_hrstdiscie(false);
w.set_hrstsentie(false);
});
}
// Wake the task to clear and re-enabled interrupts.
T::state().waker.wake();
}
}
struct State {
waker: AtomicWaker,
// Inverted logic for a default state of 0 so that the data goes into the .bss section.
drop_not_ready: AtomicBool,
}
impl State {
pub const fn new() -> Self {
Self {
waker: AtomicWaker::new(),
drop_not_ready: AtomicBool::new(false),
}
}
}
trait SealedInstance {
const REGS: crate::pac::ucpd::Ucpd;
fn state() -> &'static State;
}
/// UCPD instance trait.
#[allow(private_bounds)]
pub trait Instance: SealedInstance + PeripheralType + RccPeripheral {
/// Interrupt for this instance.
type Interrupt: crate::interrupt::typelevel::Interrupt;
}
foreach_interrupt!(
($inst:ident, ucpd, UCPD, GLOBAL, $irq:ident) => {
impl SealedInstance for crate::peripherals::$inst {
const REGS: crate::pac::ucpd::Ucpd = crate::pac::$inst;
fn state() -> &'static State {
static STATE: State = State::new();
&STATE
}
}
impl Instance for crate::peripherals::$inst {
type Interrupt = crate::interrupt::typelevel::$irq;
}
};
);
pin_trait!(Cc1Pin, Instance);
pin_trait!(Cc2Pin, Instance);
dma_trait!(TxDma, Instance);
dma_trait!(RxDma, Instance);