mirror of
https://github.com/Keychron/qmk_firmware.git
synced 2024-11-26 02:17:38 +06:00
60 lines
1.9 KiB
C
60 lines
1.9 KiB
C
/* Copyright 2020 Dimitris Papavasiliou <dpapavas@protonmail.ch>
|
|
*
|
|
* This program 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.
|
|
*
|
|
* This program 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 <https://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <LUFA/Drivers/USB/USB.h>
|
|
|
|
#include "lagrange.h"
|
|
|
|
#ifndef SPLIT_USB_TIMEOUT_POLL
|
|
# define SPLIT_USB_TIMEOUT_POLL 10
|
|
#endif
|
|
|
|
/* Instead of timing out, the slave waits indefinitely for the other
|
|
* side to signal that it has become master. This avoids both sides
|
|
* assuming the slave role when the USB port is powered but not
|
|
* otherwise active (e.g. when the host is turned off, or suspended).
|
|
* The SPI SS line is used for signaling. On power-up it is
|
|
* configured as input with pull-up enabled. When one side assumes
|
|
* the master role, it reconfigures the line for SPI, and pulls it low
|
|
* to select the slave, which doubles as the signal. */
|
|
|
|
bool is_keyboard_master(void) {
|
|
static int8_t is_master = -1;
|
|
|
|
if (is_master < 0) {
|
|
while (readPin(SPI_SS_PIN)) {
|
|
if (USB_Device_IsAddressSet()) {
|
|
is_master = 1;
|
|
return is_master;
|
|
}
|
|
wait_ms(SPLIT_USB_TIMEOUT_POLL);
|
|
}
|
|
|
|
is_master = 0;
|
|
|
|
USB_Disable();
|
|
USB_DeviceState = DEVICE_STATE_Unattached;
|
|
}
|
|
|
|
return is_master;
|
|
}
|
|
|
|
void keyboard_pre_init_kb(void) {
|
|
setPinInputHigh(SPI_SS_PIN);
|
|
|
|
keyboard_pre_init_user();
|
|
}
|