software: Implement serial port detection

1 files changed, 94 insertions, 0 deletions

diff --git a/software/vendor/go.bug.st/serial/serial_linux.go b/software/vendor/go.bug.st/serial/serial_linux.go
new file mode 100644
index 0000000..fe114d9
--- /dev/null
+++ b/software/vendor/go.bug.st/serial/serial_linux.go
@@ -0,0 +1,94 @@
+//
+// Copyright 2014-2023 Cristian Maglie. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+
+package serial
+
+import "golang.org/x/sys/unix"
+
+const devFolder = "/dev"
+const regexFilter = "(ttyS|ttyHS|ttyUSB|ttyACM|ttyAMA|rfcomm|ttyO|ttymxc)[0-9]{1,3}"
+
+// termios manipulation functions
+
+var baudrateMap = map[int]uint32{
+	0:       unix.B9600, // Default to 9600
+	50:      unix.B50,
+	75:      unix.B75,
+	110:     unix.B110,
+	134:     unix.B134,
+	150:     unix.B150,
+	200:     unix.B200,
+	300:     unix.B300,
+	600:     unix.B600,
+	1200:    unix.B1200,
+	1800:    unix.B1800,
+	2400:    unix.B2400,
+	4800:    unix.B4800,
+	9600:    unix.B9600,
+	19200:   unix.B19200,
+	38400:   unix.B38400,
+	57600:   unix.B57600,
+	115200:  unix.B115200,
+	230400:  unix.B230400,
+	460800:  unix.B460800,
+	500000:  unix.B500000,
+	576000:  unix.B576000,
+	921600:  unix.B921600,
+	1000000: unix.B1000000,
+	1152000: unix.B1152000,
+	1500000: unix.B1500000,
+	2000000: unix.B2000000,
+	2500000: unix.B2500000,
+	3000000: unix.B3000000,
+	3500000: unix.B3500000,
+	4000000: unix.B4000000,
+}
+
+var databitsMap = map[int]uint32{
+	0: unix.CS8, // Default to 8 bits
+	5: unix.CS5,
+	6: unix.CS6,
+	7: unix.CS7,
+	8: unix.CS8,
+}
+
+const tcCMSPAR = unix.CMSPAR
+const tcIUCLC = unix.IUCLC
+
+const tcCRTSCTS uint32 = unix.CRTSCTS
+
+const ioctlTcgetattr = unix.TCGETS
+const ioctlTcsetattr = unix.TCSETS
+const ioctlTcflsh = unix.TCFLSH
+const ioctlTioccbrk = unix.TIOCCBRK
+const ioctlTiocsbrk = unix.TIOCSBRK
+
+func toTermiosSpeedType(speed uint32) uint32 {
+	return speed
+}
+
+func setTermSettingsBaudrate(speed int, settings *unix.Termios) (error, bool) {
+	baudrate, ok := baudrateMap[speed]
+	if !ok {
+		return nil, true
+	}
+	// revert old baudrate
+	for _, rate := range baudrateMap {
+		settings.Cflag &^= rate
+	}
+	// set new baudrate
+	settings.Cflag |= baudrate
+	settings.Ispeed = toTermiosSpeedType(baudrate)
+	settings.Ospeed = toTermiosSpeedType(baudrate)
+	return nil, false
+}
+
+func (port *unixPort) Drain() error {
+	// It's not super well documented, but this is the same as calling tcdrain:
+	// - https://git.musl-libc.org/cgit/musl/tree/src/termios/tcdrain.c
+	// - https://elixir.bootlin.com/linux/v6.2.8/source/drivers/tty/tty_io.c#L2673
+	return unix.IoctlSetInt(port.handle, unix.TCSBRK, 1)
+}