arno/trezor-firmware
1
0
Fork 0
mirror of https://github.com/trezor/trezor-firmware.git synced 2025-02-11 07:02:41 +00:00
Code Issues Releases Wiki Activity

trezorhal/usb: do not send full packets

Browse Source
This commit is contained in:
Jan Pochyla 2017-05-24 13:46:28 +02:00
parent f7d72741fd
commit ecd5fd858b
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
micropython/trezorhal/usb_vcp-impl.h
View File

@ -408,8 +408,9 @@ static uint8_t usb_vcp_class_sof(USBD_HandleTypeDef *dev, usb_vcp_state_t *state
// Read from the tx ring buffer // Read from the tx ring buffer
usb_rbuf_t *b = &state->tx_ring; usb_rbuf_t *b = &state->tx_ring;
uint8_t *buf = state->tx_packet; uint8_t *buf = state->tx_packet;
size_t len = state->max_packet_len; // We avoid sending full packets as they stall the hosts pipeline, see:
size_t mask = b->cap - 1; // <http://www.cypress.com/?id=4&rID=92719>
size_t len = state->max_packet_len - 1;
size_t i; size_t i;
for (i = 0; (i < len) && !ring_empty(b); i++) { for (i = 0; (i < len) && !ring_empty(b); i++) {
buf[i] = b->buf[b->read & mask]; buf[i] = b->buf[b->read & mask];