openthread: fix wrong OpenThread uart read return value handling
@@ -119,7 +119,7 @@ esp_err_t esp_openthread_uart_process()
if (rval > 0) {
otPlatUartReceived(s_uart_buffer, (uint16_t)rval);
- } else if (rval > 0) {
+ } else if (rval < 0) {
if (errno != EAGAIN) {
otLogWarnPlat("read uart failed: %d", errno);
return ESP_FAIL;
