Commit 0883a7e7 authored by Pavol Rusnak's avatar Pavol Rusnak Committed by Damien George
Browse files

stmhal: Implement SNAK/CNAK mechanism for USB HID receive.

This implements flow control in case user does not call recv method often
enough (it tells host side to stop sending more data).
parent 6ace84b0
......@@ -89,7 +89,8 @@ static int8_t HID_Itf_Receive(uint8_t* Buf, uint32_t Len) {
// initiate next USB packet transfer, to append to existing data in buffer
USBD_HID_SetRxBuffer(&hUSBDDevice, buffer[current_write_buffer]);
USBD_HID_ReceivePacket(&hUSBDDevice);
// Set NAK to indicate we need to process read buffer
USBD_HID_SetNAK(&hUSBDDevice);
return USBD_OK;
}
......@@ -125,6 +126,9 @@ int USBD_HID_Rx(uint8_t *buf, uint32_t len, uint32_t timeout) {
memcpy(buf, buffer[current_read_buffer], last_read_len);
current_read_buffer = !current_read_buffer;
// Clear NAK to indicate we are ready to read more data
USBD_HID_ClearNAK(&hUSBDDevice);
// Success, return number of bytes read
return last_read_len;
}
......@@ -116,5 +116,7 @@ uint8_t USBD_HID_SetRxBuffer(USBD_HandleTypeDef *pdev, uint8_t *pbuff);
uint8_t USBD_HID_ReceivePacket(USBD_HandleTypeDef *pdev);
int USBD_HID_CanSendReport(USBD_HandleTypeDef *pdev);
uint8_t USBD_HID_SendReport(USBD_HandleTypeDef *pdev, uint8_t *report, uint16_t len);
uint8_t USBD_HID_SetNAK(USBD_HandleTypeDef *pdev);
uint8_t USBD_HID_ClearNAK(USBD_HandleTypeDef *pdev);
#endif // _USB_CDC_MSC_CORE_H_
......@@ -1093,6 +1093,24 @@ uint8_t USBD_HID_SendReport(USBD_HandleTypeDef *pdev, uint8_t *report, uint16_t
return USBD_OK;
}
uint8_t USBD_HID_SetNAK(USBD_HandleTypeDef *pdev) {
// get USBx object from pdev (needed for USBx_OUTEP macro below)
PCD_HandleTypeDef *hpcd = pdev->pData;
USB_OTG_GlobalTypeDef *USBx = hpcd->Instance;
// set NAK on HID OUT endpoint
USBx_OUTEP(HID_OUT_EP_WITH_CDC)->DOEPCTL |= USB_OTG_DOEPCTL_SNAK;
return USBD_OK;
}
uint8_t USBD_HID_ClearNAK(USBD_HandleTypeDef *pdev) {
// get USBx object from pdev (needed for USBx_OUTEP macro below)
PCD_HandleTypeDef *hpcd = pdev->pData;
USB_OTG_GlobalTypeDef *USBx = hpcd->Instance;
// clear NAK on HID OUT endpoint
USBx_OUTEP(HID_OUT_EP_WITH_CDC)->DOEPCTL |= USB_OTG_DOEPCTL_CNAK;
return USBD_OK;
}
// CDC/MSC/HID interface class callback structure
USBD_ClassTypeDef USBD_CDC_MSC_HID = {
USBD_CDC_MSC_HID_Init,
......
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment