/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
/**
* @file STM32/USBv1/usb_lld.c
* @brief STM32 USB subsystem low level driver source.
*
* @addtogroup USB
* @{
*/
#include
#include "ch.h"
#include "hal.h"
#if HAL_USE_USB || defined(__DOXYGEN__)
#define BTABLE_ADDR 0x0000
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/** @brief USB1 driver identifier.*/
#if STM32_USB_USE_USB1 || defined(__DOXYGEN__)
USBDriver USBD1;
#endif
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
/**
* @brief EP0 state.
* @note It is an union because IN and OUT endpoints are never used at the
* same time for EP0.
*/
static union {
/**
* @brief IN EP0 state.
*/
USBInEndpointState in;
/**
* @brief OUT EP0 state.
*/
USBOutEndpointState out;
} ep0_state;
/**
* @brief Buffer for the EP0 setup packets.
*/
static uint8_t ep0setup_buffer[8];
/**
* @brief EP0 initialization structure.
*/
static const USBEndpointConfig ep0config = {
USB_EP_MODE_TYPE_CTRL,
_usb_ep0setup,
_usb_ep0in,
_usb_ep0out,
0x40,
0x40,
&ep0_state.in,
&ep0_state.out,
ep0setup_buffer
};
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/**
* @brief Resets the packet memory allocator.
*
* @param[in] usbp pointer to the @p USBDriver object
*/
static void usb_pm_reset(USBDriver *usbp) {
/* The first 64 bytes are reserved for the descriptors table. The effective
available RAM for endpoint buffers is just 448 bytes.*/
usbp->pmnext = 64;
}
/**
* @brief Resets the packet memory allocator.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] size size of the packet buffer to allocate
*/
static uint32_t usb_pm_alloc(USBDriver *usbp, size_t size) {
uint32_t next;
next = usbp->pmnext;
usbp->pmnext += size;
chDbgAssert(usbp->pmnext <= USB_PMA_SIZE, "usb_pm_alloc(), #1", "PMA overflow");
return next;
}
/**
* @brief Reads from a dedicated packet buffer.
*
* @param[in] udp pointer to a @p stm32_usb_descriptor_t
* @param[out] buf buffer where to copy the packet data
* @param[in] n maximum number of bytes to copy. This value must
* not exceed the maximum packet size for this endpoint.
*
* @notapi
*/
static void usb_packet_read_to_buffer(stm32_usb_descriptor_t *udp,
uint8_t *buf, size_t n) {
uint32_t *pmap= USB_ADDR2PTR(udp->RXADDR0);
n = (n + 1) / 2;
while (n > 0) {
/* Note, this line relies on the Cortex-M3/M4 ability to perform
unaligned word accesses.*/
*(uint16_t *)buf = (uint16_t)*pmap++;
buf += 2;
n--;
}
}
/**
* @brief Reads from a dedicated packet buffer.
*
* @param[in] udp pointer to a @p stm32_usb_descriptor_t
* @param[in] iqp pointer to an @p InputQueue object
* @param[in] n maximum number of bytes to copy. This value must
* not exceed the maximum packet size for this endpoint.
*
* @notapi
*/
static void usb_packet_read_to_queue(stm32_usb_descriptor_t *udp,
InputQueue *iqp, size_t n) {
uint32_t w;
size_t nhw;
uint32_t *pmap= USB_ADDR2PTR(udp->RXADDR0);
nhw = n / 2;
while (nhw > 0) {
w = *pmap++;
*iqp->q_wrptr++ = (uint8_t)w;
if (iqp->q_wrptr >= iqp->q_top)
iqp->q_wrptr = iqp->q_buffer;
*iqp->q_wrptr++ = (uint8_t)(w >> 8);
if (iqp->q_wrptr >= iqp->q_top)
iqp->q_wrptr = iqp->q_buffer;
nhw--;
}
/* Last byte for odd numbers.*/
if ((n & 1) != 0) {
w = *pmap++;
*iqp->q_wrptr++ = (uint8_t)w;
if (iqp->q_wrptr >= iqp->q_top)
iqp->q_wrptr = iqp->q_buffer;
}
/* Updating queue.*/
chSysLockFromIsr();
iqp->q_counter += n;
while (notempty(&iqp->q_waiting))
chSchReadyI(fifo_remove(&iqp->q_waiting))->p_u.rdymsg = Q_OK;
chSysUnlockFromIsr();
}
/**
* @brief Writes to a dedicated packet buffer.
*
* @param[in] udp pointer to a @p stm32_usb_descriptor_t
* @param[in] buf buffer where to fetch the packet data
* @param[in] n maximum number of bytes to copy. This value must
* not exceed the maximum packet size for this endpoint.
*
* @notapi
*/
static void usb_packet_write_from_buffer(stm32_usb_descriptor_t *udp,
const uint8_t *buf,
size_t n) {
uint32_t *pmap = USB_ADDR2PTR(udp->TXADDR0);
udp->TXCOUNT0 = (uint16_t)n;
n = (n + 1) / 2;
while (n > 0) {
/* Note, this line relies on the Cortex-M3/M4 ability to perform
unaligned word accesses.*/
*pmap++ = *(uint16_t *)buf;
buf += 2;
n--;
}
}
/**
* @brief Prepares for a receive transaction on an OUT endpoint.
* @post The endpoint is ready for @p usbStartReceiveI().
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @param[in] n maximum number of bytes to copy
*
* @special
*/
static void usb_prepare_receive(USBDriver *usbp, usbep_t ep, size_t n) {
USBOutEndpointState *osp = usbp->epc[ep]->out_state;
osp->rxsize = n;
osp->rxcnt = 0;
/* Transfer initialization.*/
if (osp->rxsize == 0) /* Special case for zero sized packets.*/
osp->rxpkts = 1;
else
osp->rxpkts = (uint16_t)((n + usbp->epc[ep]->out_maxsize - 1) /
usbp->epc[ep]->out_maxsize);
}
/**
* @brief Prepares for a transmit transaction on an IN endpoint.
* @post The endpoint is ready for @p usbStartTransmitI().
* @note The transmit transaction size is equal to the data contained
* in the queue.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @param[in] n maximum number of bytes to copy
*
* @special
*/
static void usb_prepare_transmit(USBDriver *usbp, usbep_t ep, size_t n) {
USBInEndpointState *isp = usbp->epc[ep]->in_state;
isp->txsize = n;
isp->txcnt = 0;
/* Transfer initialization.*/
if (n > (size_t)usbp->epc[ep]->in_maxsize)
n = (size_t)usbp->epc[ep]->in_maxsize;
usb_packet_write_from_buffer(USB_GET_DESCRIPTOR(ep),
isp->mode.linear.txbuf, n);
}
/*===========================================================================*/
/* Driver interrupt handlers. */
/*===========================================================================*/
#if STM32_USB_USE_USB1 || defined(__DOXYGEN__)
/**
* @brief USB high priority interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(Vector8C) {
CH_IRQ_PROLOGUE();
CH_IRQ_EPILOGUE();
}
/**
* @brief USB low priority interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(Vector90) {
uint32_t istr;
size_t n;
USBDriver *usbp = &USBD1;
CH_IRQ_PROLOGUE();
istr = STM32_USB->ISTR;
/* USB bus reset condition handling.*/
if (istr & ISTR_RESET) {
_usb_reset(usbp);
_usb_isr_invoke_event_cb(usbp, USB_EVENT_RESET);
STM32_USB->ISTR = ~ISTR_RESET;
}
/* USB bus SUSPEND condition handling.*/
if (istr & ISTR_SUSP) {
STM32_USB->CNTR |= CNTR_FSUSP;
_usb_isr_invoke_event_cb(usbp, USB_EVENT_SUSPEND);
#if STM32_USB_LOW_POWER_ON_SUSPEND
STM32_USB->CNTR |= CNTR_LP_MODE;
#endif
STM32_USB->ISTR = ~ISTR_SUSP;
}
/* USB bus WAKEUP condition handling.*/
if (istr & ISTR_WKUP) {
uint32_t fnr = STM32_USB->FNR;
if (!(fnr & FNR_RXDP)) {
STM32_USB->CNTR &= ~CNTR_FSUSP;
_usb_isr_invoke_event_cb(usbp, USB_EVENT_WAKEUP);
}
#if STM32_USB_LOW_POWER_ON_SUSPEND
else {
/* Just noise, going back in SUSPEND mode, reference manual 22.4.5,
table 169.*/
STM32_USB->CNTR |= CNTR_LP_MODE;
}
#endif
STM32_USB->ISTR = ~ISTR_WKUP;
}
/* SOF handling.*/
if (istr & ISTR_SOF) {
_usb_isr_invoke_sof_cb(usbp);
STM32_USB->ISTR = ~ISTR_SOF;
}
/* Endpoint events handling.*/
while (istr & ISTR_CTR) {
uint32_t ep;
uint32_t epr = STM32_USB->EPR[ep = istr & ISTR_EP_ID_MASK];
const USBEndpointConfig *epcp = usbp->epc[ep];
if (epr & EPR_CTR_TX) {
/* IN endpoint, transmission.*/
EPR_CLEAR_CTR_TX(ep);
n = (size_t)USB_GET_DESCRIPTOR(ep)->TXCOUNT0;
epcp->in_state->mode.linear.txbuf += n;
epcp->in_state->txcnt += n;
epcp->in_state->txsize -= n;
if (epcp->in_state->txsize > 0) {
/* Transfer not completed, there are more packets to send.*/
if (epcp->in_state->txsize > epcp->in_maxsize)
n = epcp->in_maxsize;
else
n = epcp->in_state->txsize;
usb_packet_write_from_buffer(USB_GET_DESCRIPTOR(ep),
epcp->in_state->mode.linear.txbuf,
n);
usb_lld_start_in(usbp, ep);
}
else {
/* Transfer completed, invokes the callback.*/
_usb_isr_invoke_in_cb(usbp, ep);
}
}
if (epr & EPR_CTR_RX) {
EPR_CLEAR_CTR_RX(ep);
/* OUT endpoint, receive.*/
if (epr & EPR_SETUP) {
/* Setup packets handling, setup packets are handled using a
specific callback.*/
_usb_isr_invoke_setup_cb(usbp, ep);
}
else {
stm32_usb_descriptor_t *udp = USB_GET_DESCRIPTOR(ep);
n = (size_t)udp->RXCOUNT0 & RXCOUNT_COUNT_MASK;
/* Reads the packet into the linear buffer.*/
usb_packet_read_to_buffer(udp, epcp->out_state->mode.linear.rxbuf, n);
/* Transaction data updated.*/
epcp->out_state->mode.linear.rxbuf += n;
epcp->out_state->rxcnt += n;
epcp->out_state->rxsize -= n;
epcp->out_state->rxpkts -= 1;
if (epcp->out_state->rxpkts > 0) {
/* Transfer not completed, there are more packets to receive.*/
EPR_SET_STAT_RX(ep, EPR_STAT_RX_VALID);
}
else {
/* Transfer completed, invokes the callback.*/
_usb_isr_invoke_out_cb(usbp, ep);
}
}
}
istr = STM32_USB->ISTR;
}
CH_IRQ_EPILOGUE();
}
#endif
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Low level USB driver initialization.
*
* @notapi
*/
void usb_lld_init(void) {
/* Driver initialization.*/
usbObjectInit(&USBD1);
}
/**
* @brief Configures and activates the USB peripheral.
*
* @param[in] usbp pointer to the @p USBDriver object
*
* @notapi
*/
void usb_lld_start(USBDriver *usbp) {
if (usbp->state == USB_STOP) {
/* Clock activation.*/
#if STM32_USB_USE_USB1
if (&USBD1 == usbp) {
/* USB clock enabled.*/
rccEnableUSB(FALSE);
/* Powers up the transceiver while holding the USB in reset state.*/
STM32_USB->CNTR = CNTR_FRES;
/* Enabling the USB IRQ vectors, this also gives enough time to allow
the transceiver power up (1uS).*/
nvicEnableVector(19,
CORTEX_PRIORITY_MASK(STM32_USB_USB1_HP_IRQ_PRIORITY));
nvicEnableVector(20,
CORTEX_PRIORITY_MASK(STM32_USB_USB1_LP_IRQ_PRIORITY));
/* Releases the USB reset.*/
STM32_USB->CNTR = 0;
}
#endif
/* Reset procedure enforced on driver start.*/
_usb_reset(usbp);
}
/* Configuration.*/
}
/**
* @brief Deactivates the USB peripheral.
*
* @param[in] usbp pointer to the @p USBDriver object
*
* @notapi
*/
void usb_lld_stop(USBDriver *usbp) {
/* If in ready state then disables the USB clock.*/
if (usbp->state == USB_STOP) {
#if STM32_USB_USE_USB1
if (&USBD1 == usbp) {
nvicDisableVector(19);
nvicDisableVector(20);
STM32_USB->CNTR = CNTR_PDWN | CNTR_FRES;
rccDisableUSB(FALSE);
}
#endif
}
}
/**
* @brief USB low level reset routine.
*
* @param[in] usbp pointer to the @p USBDriver object
*
* @notapi
*/
void usb_lld_reset(USBDriver *usbp) {
uint32_t cntr;
/* Post reset initialization.*/
STM32_USB->BTABLE = 0;
STM32_USB->ISTR = 0;
STM32_USB->DADDR = DADDR_EF;
cntr = /*CNTR_ESOFM | */ CNTR_RESETM | CNTR_SUSPM |
CNTR_WKUPM | /*CNTR_ERRM | CNTR_PMAOVRM |*/ CNTR_CTRM;
/* The SOF interrupt is only enabled if a callback is defined for
this service because it is an high rate source.*/
if (usbp->config->sof_cb != NULL)
cntr |= CNTR_SOFM;
STM32_USB->CNTR = cntr;
/* Resets the packet memory allocator.*/
usb_pm_reset(usbp);
/* EP0 initialization.*/
usbp->epc[0] = &ep0config;
usb_lld_init_endpoint(usbp, 0);
}
/**
* @brief Sets the USB address.
*
* @param[in] usbp pointer to the @p USBDriver object
*
* @notapi
*/
void usb_lld_set_address(USBDriver *usbp) {
STM32_USB->DADDR = (uint32_t)(usbp->address) | DADDR_EF;
}
/**
* @brief Enables an endpoint.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*
* @notapi
*/
void usb_lld_init_endpoint(USBDriver *usbp, usbep_t ep) {
uint16_t nblocks, epr;
stm32_usb_descriptor_t *dp;
const USBEndpointConfig *epcp = usbp->epc[ep];
/* Setting the endpoint type.*/
switch (epcp->ep_mode & USB_EP_MODE_TYPE) {
case USB_EP_MODE_TYPE_ISOC:
epr = EPR_EP_TYPE_ISO;
break;
case USB_EP_MODE_TYPE_BULK:
epr = EPR_EP_TYPE_BULK;
break;
case USB_EP_MODE_TYPE_INTR:
epr = EPR_EP_TYPE_INTERRUPT;
break;
default:
epr = EPR_EP_TYPE_CONTROL;
}
/* IN endpoint initially in NAK mode.*/
if (epcp->in_cb != NULL)
epr |= EPR_STAT_TX_NAK;
/* OUT endpoint initially in NAK mode.*/
if (epcp->out_cb != NULL)
epr |= EPR_STAT_RX_NAK;
/* EPxR register setup.*/
EPR_SET(ep, epr | ep);
EPR_TOGGLE(ep, epr);
/* Endpoint size and address initialization.*/
if (epcp->out_maxsize > 62)
nblocks = (((((epcp->out_maxsize - 1) | 0x1f) + 1) / 32) << 10) |
0x8000;
else
nblocks = ((((epcp->out_maxsize - 1) | 1) + 1) / 2) << 10;
dp = USB_GET_DESCRIPTOR(ep);
dp->TXCOUNT0 = 0;
dp->RXCOUNT0 = nblocks;
dp->TXADDR0 = usb_pm_alloc(usbp, epcp->in_maxsize);
dp->RXADDR0 = usb_pm_alloc(usbp, epcp->out_maxsize);
}
/**
* @brief Disables all the active endpoints except the endpoint zero.
*
* @param[in] usbp pointer to the @p USBDriver object
*
* @notapi
*/
void usb_lld_disable_endpoints(USBDriver *usbp) {
unsigned i;
/* Resets the packet memory allocator.*/
usb_pm_reset(usbp);
/* Disabling all endpoints.*/
for (i = 1; i <= USB_ENDOPOINTS_NUMBER; i++) {
EPR_TOGGLE(i, 0);
EPR_SET(i, 0);
}
}
/**
* @brief Returns the status of an OUT endpoint.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @return The endpoint status.
* @retval EP_STATUS_DISABLED The endpoint is not active.
* @retval EP_STATUS_STALLED The endpoint is stalled.
* @retval EP_STATUS_ACTIVE The endpoint is active.
*
* @notapi
*/
usbepstatus_t usb_lld_get_status_out(USBDriver *usbp, usbep_t ep) {
(void)usbp;
switch (STM32_USB->EPR[ep] & EPR_STAT_RX_MASK) {
case EPR_STAT_RX_DIS:
return EP_STATUS_DISABLED;
case EPR_STAT_RX_STALL:
return EP_STATUS_STALLED;
default:
return EP_STATUS_ACTIVE;
}
}
/**
* @brief Returns the status of an IN endpoint.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @return The endpoint status.
* @retval EP_STATUS_DISABLED The endpoint is not active.
* @retval EP_STATUS_STALLED The endpoint is stalled.
* @retval EP_STATUS_ACTIVE The endpoint is active.
*
* @notapi
*/
usbepstatus_t usb_lld_get_status_in(USBDriver *usbp, usbep_t ep) {
(void)usbp;
switch (STM32_USB->EPR[ep] & EPR_STAT_TX_MASK) {
case EPR_STAT_TX_DIS:
return EP_STATUS_DISABLED;
case EPR_STAT_TX_STALL:
return EP_STATUS_STALLED;
default:
return EP_STATUS_ACTIVE;
}
}
/**
* @brief Reads a setup packet from the dedicated packet buffer.
* @details This function must be invoked in the context of the @p setup_cb
* callback in order to read the received setup packet.
* @pre In order to use this function the endpoint must have been
* initialized as a control endpoint.
* @post The endpoint is ready to accept another packet.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @param[out] buf buffer where to copy the packet data
*
* @notapi
*/
void usb_lld_read_setup(USBDriver *usbp, usbep_t ep, uint8_t *buf) {
uint32_t *pmap;
stm32_usb_descriptor_t *udp;
uint32_t n;
(void)usbp;
udp = USB_GET_DESCRIPTOR(ep);
pmap = USB_ADDR2PTR(udp->RXADDR0);
for (n = 0; n < 4; n++) {
*(uint16_t *)buf = (uint16_t)*pmap++;
buf += 2;
}
}
/**
* @brief Prepares for a receive operation.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @param[out] buf buffer where to copy the received data
* @param[in] n maximum number of bytes to copy
*
* @notapi
*/
void usb_lld_prepare_receive(USBDriver *usbp, usbep_t ep,
uint8_t *buf, size_t n) {
USBOutEndpointState *osp = usbp->epc[ep]->out_state;
osp->rxqueued = FALSE;
osp->mode.linear.rxbuf = buf;
usb_prepare_receive(usbp, ep, n);
}
/**
* @brief Prepares for a transmit operation.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @param[in] buf buffer where to fetch the data to be transmitted
* @param[in] n maximum number of bytes to copy
*
* @notapi
*/
void usb_lld_prepare_transmit(USBDriver *usbp, usbep_t ep,
const uint8_t *buf, size_t n) {
USBInEndpointState *isp = usbp->epc[ep]->in_state;
isp->txqueued = FALSE;
isp->mode.linear.txbuf = buf;
usb_prepare_transmit(usbp, ep, n);
}
/**
* @brief Prepares for a receive transaction on an OUT endpoint.
* @post The endpoint is ready for @p usbStartReceiveI().
* @note The receive transaction size is equal to the space in the queue
* rounded to the lower multiple of a packet size. Make sure there
* is room for at least one packet in the queue before starting
* the receive operation.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @param[in] iq input queue to be filled with incoming data
* @param[in] n maximum number of bytes to copy
*
* @special
*/
void usb_lld_prepare_queued_receive(USBDriver *usbp, usbep_t ep,
InputQueue *iq, size_t n) {
USBOutEndpointState *osp = usbp->epc[ep]->out_state;
osp->rxqueued = TRUE;
osp->mode.queue.rxqueue = iq;
usb_prepare_receive(usbp, ep, n);
}
/**
* @brief Prepares for a transmit transaction on an IN endpoint.
* @post The endpoint is ready for @p usbStartTransmitI().
* @note The transmit transaction size is equal to the data contained
* in the queue.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @param[in] oq output queue to be fetched for outgoing data
* @param[in] n maximum number of bytes to copy
*
* @special
*/
void usb_lld_prepare_queued_transmit(USBDriver *usbp, usbep_t ep,
OutputQueue *oq, size_t n) {
USBInEndpointState *isp = usbp->epc[ep]->in_state;
isp->txqueued = TRUE;
isp->mode.queue.txqueue = oq;
usb_prepare_transmit(usbp, ep, n);
}
/**
* @brief Starts a receive operation on an OUT endpoint.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*
* @notapi
*/
void usb_lld_start_out(USBDriver *usbp, usbep_t ep) {
(void)usbp;
EPR_SET_STAT_RX(ep, EPR_STAT_RX_VALID);
}
/**
* @brief Starts a transmit operation on an IN endpoint.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*
* @notapi
*/
void usb_lld_start_in(USBDriver *usbp, usbep_t ep) {
(void)usbp;
EPR_SET_STAT_TX(ep, EPR_STAT_TX_VALID);
}
/**
* @brief Brings an OUT endpoint in the stalled state.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*
* @notapi
*/
void usb_lld_stall_out(USBDriver *usbp, usbep_t ep) {
(void)usbp;
EPR_SET_STAT_RX(ep, EPR_STAT_RX_STALL);
}
/**
* @brief Brings an IN endpoint in the stalled state.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*
* @notapi
*/
void usb_lld_stall_in(USBDriver *usbp, usbep_t ep) {
(void)usbp;
EPR_SET_STAT_TX(ep, EPR_STAT_TX_STALL);
}
/**
* @brief Brings an OUT endpoint in the active state.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*
* @notapi
*/
void usb_lld_clear_out(USBDriver *usbp, usbep_t ep) {
(void)usbp;
/* Makes sure to not put to NAK an endpoint that is already
transferring.*/
if ((STM32_USB->EPR[ep] & EPR_STAT_RX_MASK) != EPR_STAT_RX_VALID)
EPR_SET_STAT_TX(ep, EPR_STAT_RX_NAK);
}
/**
* @brief Brings an IN endpoint in the active state.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*
* @notapi
*/
void usb_lld_clear_in(USBDriver *usbp, usbep_t ep) {
(void)usbp;
/* Makes sure to not put to NAK an endpoint that is already
transferring.*/
if ((STM32_USB->EPR[ep] & EPR_STAT_TX_MASK) != EPR_STAT_TX_VALID)
EPR_SET_STAT_TX(ep, EPR_STAT_TX_NAK);
}
#endif /* HAL_USE_USB */
/** @} */