/**
* @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) {
USBOutEndpointState *osp = usbp->epc[ep]->out_state;
/* Transfer initialization.*/
if (osp->rxsize == 0) /* Special case for zero sized packets.*/
osp->rxpkts = 1;
else
osp->rxpkts = (uint16_t)((osp->rxsize + usbp->epc[ep]->out_maxsize - 1) /
usbp->epc[ep]->out_maxsize);
EPR_SET_STAT_RX(ep, EPR_STAT_RX_VALID);
}
/**
* @brief Starts a receive operation on an OUT endpoint.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
* @param[out] buf buffer where to copy the endpoint data
* @param[in] n maximum number of bytes to copy in the buffer
*
* @notapi
*/
void usb_lld_start_out(USBDriver *usbp, usbep_t ep,
uint8_t *buf, size_t n) {
USBOutEndpointState *osp = usbp->epc[ep]->out_state;
osp->rxbuf = buf;
osp->rxsize = n;
osp->rxcnt = 0;
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);
EPR_SET_STAT_RX(ep, EPR_STAT_RX_VALID);
}
/**
* @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->RXADDR);
for (n = 0; n < 4; n++) {
*(uint16_t *)buf = (uint16_t)*pmap++;
buf += 2;
}
EPR_SET_STAT_RX(ep, EPR_STAT_RX_VALID);
}
/**
* @brief Reads a packet from the dedicated packet buffer.
* @pre In order to use this function he endpoint must have been
* initialized in packet mode.
* @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
* @param[in] n maximum number of bytes to copy. This value must
* not exceed the maximum packet size for this endpoint.
* @return The received packet size regardless the specified
* @p n parameter.
* @retval 0 Zero size packet received.
*
* @notapi
*/
size_t usb_lld_read_packet(USBDriver *usbp, usbep_t ep,
uint8_t *buf, size_t n) {
uint32_t *pmap;
stm32_usb_descriptor_t *udp;
size_t count;
(void)usbp;
udp = USB_GET_DESCRIPTOR(ep);
pmap = USB_ADDR2PTR(udp->RXADDR);
count = udp->RXCOUNT & RXCOUNT_COUNT_MASK;
if (n > count)
n = count;
n = (n + 1) / 2;
while (n > 0) {
*(uint16_t *)buf = (uint16_t)*pmap++;
buf += 2;
n--;
}
EPR_SET_STAT_RX(ep, EPR_STAT_RX_VALID);
return count;
}
/**
* @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 Common ISR code, serves the EP-related interrupts.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*
* @notapi
*/
static void usb_serve_endpoints(USBDriver *usbp, uint32_t ep) {
size_t n;
uint32_t epr = STM32_USB->EPR[ep];
const USBEndpointConfig *epcp = usbp->epc[ep];
if (epr & EPR_CTR_TX) {
/* IN endpoint, transmission.*/
USBInEndpointState *isp = epcp->in_state;
EPR_CLEAR_CTR_TX(ep);
isp->txcnt += isp->txlast;
n = isp->txsize - isp->txcnt;
if (n > 0) {
/* Transfer not completed, there are more packets to send.*/
if (n > epcp->in_maxsize)
n = epcp->in_maxsize;
/* Writes the packet from the defined buffer.*/
isp->txbuf += isp->txlast;
isp->txlast = n;
usb_packet_write_from_buffer(ep, isp->txbuf, n);
/* Starting IN operation.*/
EPR_SET_STAT_TX(ep, EPR_STAT_TX_VALID);
}
else {
/* Transfer completed, invokes the callback.*/
_usb_isr_invoke_in_cb(usbp, ep);
}
}
if (epr & EPR_CTR_RX) {
/* OUT endpoint, receive.*/
EPR_CLEAR_CTR_RX(ep);
if (epr & EPR_SETUP) {
/* Setup packets handling, setup packets are handled using a
specific callback.*/
_usb_isr_invoke_setup_cb(usbp, ep);
}
else {
USBOutEndpointState *osp = epcp->out_state;
/* Reads the packet into the defined buffer.*/
n = usb_packet_read_to_buffer(ep, osp->rxbuf);
osp->rxbuf += n;
/* Transaction data updated.*/
osp->rxcnt += n;
osp->rxsize -= n;
osp->rxpkts -= 1;
/* The transaction is completed if the specified number of packets
has been received or the current packet is a short packet.*/
if ((n < epcp->out_maxsize) || (osp->rxpkts == 0)) {
/* Transfer complete, invokes the callback.*/
_usb_isr_invoke_out_cb(usbp, ep);
}
else {
/* Transfer not complete, there are more packets to receive.*/
EPR_SET_STAT_RX(ep, EPR_STAT_RX_VALID);
}
}
}
}
/**
* @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);
}
