]> sigrok.org Git - libsigrok.git/blobdiff - hardware/common/serial.c
Route sr_source_remove for all serial devices through a wrapper.
[libsigrok.git] / hardware / common / serial.c
index 2980d523bbe7c39d7df0cc8860e36c8ce4dcff3b..af80356a3cc72a714627a272e0a420c1a22e28d0 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * This file is part of the sigrok project.
+ * This file is part of the libsigrok project.
  *
  * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
  * Copyright (C) 2010-2012 Uwe Hermann <uwe@hermann-uwe.de>
  */
 
 #include <string.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#ifdef _WIN32
-#include <windows.h>
-#else
-#include <glob.h>
-#include <termios.h>
-#include <sys/ioctl.h>
-#endif
 #include <stdlib.h>
-#include <errno.h>
 #include <glib.h>
+#include <libserialport.h>
 #include "libsigrok.h"
 #include "libsigrok-internal.h"
 
-/* Message logging helpers with driver-specific prefix string. */
-#define DRIVER_LOG_DOMAIN "serial: "
-#define sr_log(l, s, args...) sr_log(l, DRIVER_LOG_DOMAIN s, ## args)
-#define sr_spew(s, args...) sr_spew(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_dbg(s, args...) sr_dbg(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_info(s, args...) sr_info(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_warn(s, args...) sr_warn(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_err(s, args...) sr_err(DRIVER_LOG_DOMAIN s, ## args)
-
-// FIXME: Must be moved, or rather passed as function argument.
-#ifdef _WIN32
-static HANDLE hdl;
-#endif
+/* Message logging helpers with subsystem-specific prefix string. */
+#define LOG_PREFIX "serial: "
+#define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
+#define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
+#define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
+#define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
+#define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
+#define sr_err(s, args...) sr_err(LOG_PREFIX s, ## args)
 
 /**
  * Open the specified serial port.
@@ -65,10 +49,9 @@ static HANDLE hdl;
  */
 SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
 {
-       int flags_local = 0;
-#ifdef _WIN32
-       DWORD desired_access = 0, flags_and_attributes = 0;
-#endif
+       int ret;
+       char *error;
+       int sp_flags = 0;
 
        if (!serial) {
                sr_dbg("Invalid serial port.");
@@ -77,37 +60,30 @@ SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
 
        sr_spew("Opening serial port '%s' (flags %d).", serial->port, flags);
 
-#ifdef _WIN32
-       /* Map 'flags' to the OS-specific settings. */
-       desired_access |= GENERIC_READ;
-       flags_and_attributes = FILE_ATTRIBUTE_NORMAL;
-       if (flags & SERIAL_RDWR)
-               desired_access |= GENERIC_WRITE;
-       if (flags & SERIAL_NONBLOCK)
-               flags_and_attributes |= FILE_FLAG_OVERLAPPED;
-
-       hdl = CreateFile(serial->port, desired_access, 0, 0,
-                        OPEN_EXISTING, flags_and_attributes, 0);
-       if (hdl == INVALID_HANDLE_VALUE) {
-               sr_err("Error opening serial port '%s'.", serial->port);
-               return SR_ERR;
-       }
-#else
-       /* Map 'flags' to the OS-specific settings. */
+       sp_get_port_by_name(serial->port, &serial->data);
+
        if (flags & SERIAL_RDWR)
-               flags_local |= O_RDWR;
-       if (flags & SERIAL_RDONLY)
-               flags_local |= O_RDONLY;
-       if (flags & SERIAL_NONBLOCK)
-               flags_local |= O_NONBLOCK;
-
-       if ((serial->fd = open(serial->port, flags_local)) < 0) {
-               sr_err("Error opening serial port '%s': %s.", serial->port,
-                      strerror(errno));
+               sp_flags = (SP_MODE_READ | SP_MODE_WRITE);
+       else if (flags & SERIAL_RDONLY)
+               sp_flags = SP_MODE_READ;
+
+       serial->nonblocking = (flags & SERIAL_NONBLOCK) ? 1 : 0;
+
+       ret = sp_open(serial->data, sp_flags);
+
+       switch (ret) {
+       case SP_ERR_ARG:
+               sr_err("Attempt to open serial port with invalid parameters.");
+               return SR_ERR_ARG;
+       case SP_ERR_FAIL:
+               error = sp_last_error_message();
+               sr_err("Error opening port: %s.", error);
+               sp_free_error_message(error);
                return SR_ERR;
        }
 
-       sr_spew("Opened serial port '%s' (fd %d).", serial->port, serial->fd);
+#ifndef _WIN32
+       sp_get_port_handle(serial->data, &serial->fd);
 #endif
 
        if (serial->serialcomm)
@@ -126,6 +102,7 @@ SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
 SR_PRIV int serial_close(struct sr_serial_dev_inst *serial)
 {
        int ret;
+       char *error;
 
        if (!serial) {
                sr_dbg("Invalid serial port.");
@@ -139,24 +116,24 @@ SR_PRIV int serial_close(struct sr_serial_dev_inst *serial)
        }
 
        sr_spew("Closing serial port %s (fd %d).", serial->port, serial->fd);
-       ret = SR_OK;
-
-#ifdef _WIN32
-       /* Returns non-zero upon success, 0 upon failure. */
-       if (CloseHandle(hdl) == 0)
-               ret = SR_ERR;
-#else
-       /* Returns 0 upon success, -1 upon failure. */
-       if (close(serial->fd) < 0) {
-               sr_err("Error closing serial port: %s (fd %d).", strerror(errno),
-                               serial->fd);
-               ret = SR_ERR;
+
+       ret = sp_close(serial->data);
+       sp_free_port(serial->data);
+
+       switch (ret) {
+       case SP_ERR_ARG:
+               sr_err("Attempt to close an invalid serial port.");
+               return SR_ERR_ARG;
+       case SP_ERR_FAIL:
+               error = sp_last_error_message();
+               sr_err("Error closing port: %s.", error);
+               sp_free_error_message(error);
+               return SR_ERR;
        }
-#endif
 
        serial->fd = -1;
 
-       return ret;
+       return SR_OK;
 }
 
 /**
@@ -169,6 +146,7 @@ SR_PRIV int serial_close(struct sr_serial_dev_inst *serial)
 SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
 {
        int ret;
+       char *error;
 
        if (!serial) {
                sr_dbg("Invalid serial port.");
@@ -182,23 +160,21 @@ SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
        }
 
        sr_spew("Flushing serial port %s (fd %d).", serial->port, serial->fd);
-       ret = SR_OK;
 
-#ifdef _WIN32
-       /* Returns non-zero upon success, 0 upon failure. */
-       if (PurgeComm(hdl, PURGE_RXCLEAR | PURGE_TXCLEAR) == 0) {
-               sr_err("Error flushing serial port: %s.", strerror(errno));
-               ret = SR_ERR;
-       }
-#else
-       /* Returns 0 upon success, -1 upon failure. */
-       if (tcflush(serial->fd, TCIOFLUSH) < 0) {
-               sr_err("Error flushing serial port: %s.", strerror(errno));
-               ret = SR_ERR;
+       ret = sp_flush(serial->data, SP_BUF_BOTH);
+
+       switch (ret) {
+       case SP_ERR_ARG:
+               sr_err("Attempt to flush an invalid serial port.");
+               return SR_ERR_ARG;
+       case SP_ERR_FAIL:
+               error = sp_last_error_message();
+               sr_err("Error flushing port: %s.", error);
+               sp_free_error_message(error);
+               return SR_ERR;
        }
 
-       return ret;
-#endif
+       return SR_OK;
 }
 
 /**
@@ -208,38 +184,42 @@ SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
  * @param buf Buffer containing the bytes to write.
  * @param count Number of bytes to write.
  *
- * @return The number of bytes written, or -1 upon failure.
+ * @return The number of bytes written, or a negative error code upon failure.
  */
 SR_PRIV int serial_write(struct sr_serial_dev_inst *serial,
                const void *buf, size_t count)
 {
        ssize_t ret;
+       char *error;
 
        if (!serial) {
                sr_dbg("Invalid serial port.");
-               return -1;
+               return SR_ERR;
        }
 
        if (serial->fd == -1) {
                sr_dbg("Cannot use unopened serial port %s (fd %d).",
                                serial->port, serial->fd);
-               return -1;
+               return SR_ERR;
        }
 
-#ifdef _WIN32
-       DWORD tmp = 0;
-
-       /* FIXME */
-       /* Returns non-zero upon success, 0 upon failure. */
-       WriteFile(hdl, buf, count, &tmp, NULL);
-#else
-       /* Returns the number of bytes written, or -1 upon failure. */
-       ret = write(serial->fd, buf, count);
-       if (ret < 0)
-               sr_err("Write error: %s.", strerror(errno));
+       if (serial->nonblocking)
+               ret = sp_nonblocking_write(serial->data, buf, count);
        else
-               sr_spew("Wrote %d/%d bytes (fd %d).", ret, count, serial->fd);
-#endif
+               ret = sp_blocking_write(serial->data, buf, count, 0);
+
+       switch (ret) {
+       case SP_ERR_ARG:
+               sr_err("Attempted serial port write with invalid arguments.");
+               return SR_ERR_ARG;
+       case SP_ERR_FAIL:
+               error = sp_last_error_message();
+               sr_err("Write error: %s.", error);
+               sp_free_error_message(error);
+               return SR_ERR;
+       }
+
+       sr_spew("Wrote %d/%d bytes (fd %d).", ret, count, serial->fd);
 
        return ret;
 }
@@ -251,34 +231,43 @@ SR_PRIV int serial_write(struct sr_serial_dev_inst *serial,
  * @param buf Buffer where to store the bytes that are read.
  * @param count The number of bytes to read.
  *
- * @return The number of bytes read, or -1 upon failure.
+ * @return The number of bytes read, or a negative error code upon failure.
  */
 SR_PRIV int serial_read(struct sr_serial_dev_inst *serial, void *buf,
                size_t count)
 {
        ssize_t ret;
+       char *error;
 
        if (!serial) {
                sr_dbg("Invalid serial port.");
-               return -1;
+               return SR_ERR;
        }
 
        if (serial->fd == -1) {
                sr_dbg("Cannot use unopened serial port %s (fd %d).",
                                serial->port, serial->fd);
-               return -1;
+               return SR_ERR;
        }
 
-#ifdef _WIN32
-       DWORD tmp = 0;
+       if (serial->nonblocking)
+               ret = sp_nonblocking_read(serial->data, buf, count);
+       else
+               ret = sp_blocking_read(serial->data, buf, count, 0);
 
-       /* FIXME */
-       /* Returns non-zero upon success, 0 upon failure. */
-       return ReadFile(hdl, buf, count, &tmp, NULL);
-#else
-       /* Returns the number of bytes read, or -1 upon failure. */
-       ret = read(serial->fd, buf, count);
-#endif
+       switch (ret) {
+       case SP_ERR_ARG:
+               sr_err("Attempted serial port read with invalid arguments.");
+               return SR_ERR_ARG;
+       case SP_ERR_FAIL:
+               error = sp_last_error_message();
+               sr_err("Read error: %s.", error);
+               sp_free_error_message(error);
+               return SR_ERR;
+       }
+
+       if (ret > 0)
+               sr_spew("Read %d/%d bytes (fd %d).", ret, count, serial->fd);
 
        return ret;
 }
@@ -300,6 +289,10 @@ SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
                              int bits, int parity, int stopbits,
                              int flowcontrol, int rts, int dtr)
 {
+       int ret;
+       char *error;
+       struct sp_port_config *config;
+
        if (!serial) {
                sr_dbg("Invalid serial port.");
                return SR_ERR;
@@ -314,319 +307,43 @@ SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
        sr_spew("Setting serial parameters on port %s (fd %d).", serial->port,
                serial->fd);
 
-#ifdef _WIN32
-       DCB dcb;
-
-       if (!GetCommState(hdl, &dcb)) {
-               sr_err("Failed to get comm state on port %s (fd %d): %d.",
-                      serial->port, serial->fd, GetLastError());
-               return SR_ERR;
-       }
-
-       switch (baudrate) {
-       /*
-        * The baudrates 50/75/134/150/200/1800/230400/460800 do not seem to
-        * have documented CBR_* macros.
-        */
-       case 110:
-               dcb.BaudRate = CBR_110;
-               break;
-       case 300:
-               dcb.BaudRate = CBR_300;
-               break;
-       case 600:
-               dcb.BaudRate = CBR_600;
-               break;
-       case 1200:
-               dcb.BaudRate = CBR_1200;
-               break;
-       case 2400:
-               dcb.BaudRate = CBR_2400;
-               break;
-       case 4800:
-               dcb.BaudRate = CBR_4800;
-               break;
-       case 9600:
-               dcb.BaudRate = CBR_9600;
-               break;
-       case 14400:
-               dcb.BaudRate = CBR_14400; /* Not available on Unix? */
-               break;
-       case 19200:
-               dcb.BaudRate = CBR_19200;
-               break;
-       case 38400:
-               dcb.BaudRate = CBR_38400;
-               break;
-       case 57600:
-               dcb.BaudRate = CBR_57600;
-               break;
-       case 115200:
-               dcb.BaudRate = CBR_115200;
-               break;
-       case 128000:
-               dcb.BaudRate = CBR_128000; /* Not available on Unix? */
-               break;
-       case 256000:
-               dcb.BaudRate = CBR_256000; /* Not available on Unix? */
-               break;
-       default:
-               sr_err("Unsupported baudrate: %d.", baudrate);
-               return SR_ERR;
-       }
-       sr_spew("Configuring baudrate to %d (%d).", baudrate, dcb.BaudRate);
-
-       sr_spew("Configuring %d data bits.", bits);
-       dcb.ByteSize = bits;
-
-       sr_spew("Configuring %d stop bits.", stopbits);
-       switch (stopbits) {
-       /* Note: There's also ONE5STOPBITS == 1.5 (unneeded so far). */
-       case 1:
-               dcb.StopBits = ONESTOPBIT;
-               break;
-       case 2:
-               dcb.StopBits = TWOSTOPBITS;
-               break;
-       default:
-               sr_err("Unsupported stopbits number: %d.", stopbits);
-               return SR_ERR;
-       }
-
+       sp_new_config(&config);
+       sp_set_config_baudrate(config, baudrate);
+       sp_set_config_bits(config, bits);
        switch (parity) {
-       /* Note: There's also SPACEPARITY, MARKPARITY (unneeded so far). */
-       case SERIAL_PARITY_NONE:
-               sr_spew("Configuring no parity.");
-               dcb.Parity = NOPARITY;
-               break;
-       case SERIAL_PARITY_EVEN:
-               sr_spew("Configuring even parity.");
-               dcb.Parity = EVENPARITY;
-               break;
-       case SERIAL_PARITY_ODD:
-               sr_spew("Configuring odd parity.");
-               dcb.Parity = ODDPARITY;
-               break;
-       default:
-               sr_err("Unsupported parity setting: %d.", parity);
-               return SR_ERR;
-       }
-
-       if (rts != -1) {
-               sr_spew("Setting RTS %s.", rts ? "high" : "low");
-               if (rts)
-                       dcb.fRtsControl = RTS_CONTROL_ENABLE;
-               else
-                       dcb.fRtsControl = RTS_CONTROL_DISABLE;
-       }
-
-       if (dtr != -1) {
-               sr_spew("Setting DTR %s.", dtr ? "high" : "low");
-               if (dtr)
-                       dcb.fDtrControl = DTR_CONTROL_ENABLE;
-               else
-                       dcb.fDtrControl = DTR_CONTROL_DISABLE;
-       }
-
-       if (!SetCommState(hdl, &dcb)) {
-               sr_err("Failed to set comm state on port %s (fd %d): %d.",
-                      serial->port, serial->fd, GetLastError());
-               return SR_ERR;
-       }
-#else
-       struct termios term;
-       speed_t baud;
-       int ret, controlbits;
-
-       if (tcgetattr(serial->fd, &term) < 0) {
-               sr_err("tcgetattr() error on port %s (fd %d): %s.",
-                               serial->port, serial->fd, strerror(errno));
-               return SR_ERR;
-       }
-
-       switch (baudrate) {
-       case 50:
-               baud = B50;
-               break;
-       case 75:
-               baud = B75;
-               break;
-       case 110:
-               baud = B110;
-               break;
-       case 134:
-               baud = B134;
-               break;
-       case 150:
-               baud = B150;
-               break;
-       case 200:
-               baud = B200;
-               break;
-       case 300:
-               baud = B300;
-               break;
-       case 600:
-               baud = B600;
-               break;
-       case 1200:
-               baud = B1200;
-               break;
-       case 1800:
-               baud = B1800;
-               break;
-       case 2400:
-               baud = B2400;
-               break;
-       case 4800:
-               baud = B4800;
-               break;
-       case 9600:
-               baud = B9600;
-               break;
-       case 19200:
-               baud = B19200;
-               break;
-       case 38400:
-               baud = B38400;
-               break;
-       case 57600:
-               baud = B57600;
-               break;
-       case 115200:
-               baud = B115200;
-               break;
-       case 230400:
-               baud = B230400;
-               break;
-#if !defined(__APPLE__) && !defined(__OpenBSD__)
-       case 460800:
-               baud = B460800;
-               break;
-#endif
-       default:
-               sr_err("Unsupported baudrate: %d.", baudrate);
-               return SR_ERR;
-       }
-
-       sr_spew("Configuring output baudrate to %d (%d).", baudrate, baud);
-       if (cfsetospeed(&term, baud) < 0) {
-               sr_err("cfsetospeed() error: %s.", strerror(errno));
-               return SR_ERR;
-       }
-
-       sr_spew("Configuring input baudrate to %d (%d).", baudrate, baud);
-       if (cfsetispeed(&term, baud) < 0) {
-               sr_err("cfsetispeed() error: %s.", strerror(errno));
-               return SR_ERR;
-       }
-
-       sr_spew("Configuring %d data bits.", bits);
-       term.c_cflag &= ~CSIZE;
-       switch (bits) {
-       case 8:
-               term.c_cflag |= CS8;
-               break;
-       case 7:
-               term.c_cflag |= CS7;
-               break;
-       default:
-               sr_err("Unsupported data bits number %d.", bits);
-               return SR_ERR;
-       }
-
-       sr_spew("Configuring %d stop bits.", stopbits);
-       term.c_cflag &= ~CSTOPB;
-       switch (stopbits) {
-       case 1:
-               term.c_cflag &= ~CSTOPB;
-               break;
-       case 2:
-               term.c_cflag |= CSTOPB;
-               break;
-       default:
-               sr_err("Unsupported stopbits number %d.", stopbits);
-               return SR_ERR;
-       }
-
-       term.c_iflag &= ~(IXON | IXOFF);
-       term.c_cflag &= ~CRTSCTS;
-       switch (flowcontrol) {
        case 0:
-               /* No flow control. */
-               sr_spew("Configuring no flow control.");
+               sp_set_config_parity(config, SP_PARITY_NONE);
                break;
        case 1:
-               sr_spew("Configuring RTS/CTS flow control.");
-               term.c_cflag |= CRTSCTS;
+               sp_set_config_parity(config, SP_PARITY_EVEN);
                break;
        case 2:
-               sr_spew("Configuring XON/XOFF flow control.");
-               term.c_iflag |= IXON | IXOFF;
+               sp_set_config_parity(config, SP_PARITY_ODD);
                break;
        default:
-               sr_err("Unsupported flow control setting %d.", flowcontrol);
-               return SR_ERR;
-       }
-
-       term.c_iflag &= ~IGNPAR;
-       term.c_cflag &= ~(PARODD | PARENB);
-       switch (parity) {
-       case SERIAL_PARITY_NONE:
-               sr_spew("Configuring no parity.");
-               term.c_iflag |= IGNPAR;
-               break;
-       case SERIAL_PARITY_EVEN:
-               sr_spew("Configuring even parity.");
-               term.c_cflag |= PARENB;
-               break;
-       case SERIAL_PARITY_ODD:
-               sr_spew("Configuring odd parity.");
-               term.c_cflag |= PARENB | PARODD;
-               break;
-       default:
-               sr_err("Unsupported parity setting %d.", parity);
-               return SR_ERR;
+               return SR_ERR_ARG;
        }
+       sp_set_config_stopbits(config, stopbits);
+       sp_set_config_rts(config, flowcontrol == 1 ? SP_RTS_FLOW_CONTROL : rts);
+       sp_set_config_cts(config, flowcontrol == 1 ? SP_CTS_FLOW_CONTROL : SP_CTS_IGNORE);
+       sp_set_config_dtr(config, dtr);
+       sp_set_config_dsr(config, SP_DSR_IGNORE);
+       sp_set_config_xon_xoff(config, flowcontrol == 2 ? SP_XONXOFF_INOUT : SP_XONXOFF_DISABLED);
 
-       /* Turn off all serial port cooking. */
-       term.c_iflag &= ~(ISTRIP | INLCR | ICRNL);
-       term.c_oflag &= ~(ONLCR | OCRNL | ONOCR);
-#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
-       term.c_oflag &= ~OFILL;
-#endif
-
-       /* Disable canonical mode, and don't echo input characters. */
-       term.c_lflag &= ~(ICANON | ECHO);
+       ret = sp_set_config(serial->data, config);
+       sp_free_config(config);
 
-       /* Write the configured settings. */
-       if (tcsetattr(serial->fd, TCSADRAIN, &term) < 0) {
-               sr_err("tcsetattr() error: %s.", strerror(errno));
+       switch (ret) {
+       case SP_ERR_ARG:
+               sr_err("Invalid arguments for setting serial port parameters.");
+               return SR_ERR_ARG;
+       case SP_ERR_FAIL:
+               error = sp_last_error_message();
+               sr_err("Error setting serial port parameters: %s.", error);
+               sp_free_error_message(error);
                return SR_ERR;
        }
 
-       if (rts != -1) {
-               sr_spew("Setting RTS %s.", rts ? "high" : "low");
-               controlbits = TIOCM_RTS;
-               if ((ret = ioctl(serial->fd, rts ? TIOCMBIS : TIOCMBIC,
-                               &controlbits)) < 0) {
-                       sr_err("Error setting RTS: %s.", strerror(errno));
-                       return SR_ERR;
-               }
-       }
-
-       if (dtr != -1) {
-               sr_spew("Setting DTR %s.", dtr ? "high" : "low");
-               controlbits = TIOCM_DTR;
-               if ((ret = ioctl(serial->fd, dtr ? TIOCMBIS : TIOCMBIC,
-                               &controlbits)) < 0) {
-                       sr_err("Error setting DTR: %s.", strerror(errno));
-                       return SR_ERR;
-               }
-       }
-
-#endif
-
        return SR_OK;
 }
 
@@ -640,7 +357,7 @@ SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
  *
  * @return SR_OK upon success, SR_ERR upon failure.
  */
-#define SERIAL_COMM_SPEC "^(\\d+)/([78])([neo])([12])(.*)$"
+#define SERIAL_COMM_SPEC "^(\\d+)/([5678])([neo])([12])(.*)$"
 SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
                const char *paramstr)
 {
@@ -787,7 +504,8 @@ SR_PRIV int serial_readline(struct sr_serial_dev_inst *serial, char **buf,
                if (g_get_monotonic_time() - start > timeout_ms)
                        /* Timeout */
                        break;
-               g_usleep(2000);
+               if (len < 1)
+                       g_usleep(2000);
        }
        if (*buflen)
                sr_dbg("Received %d: '%s'.", *buflen, *buf);
@@ -868,7 +586,8 @@ SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
                        sr_dbg("Detection timed out after %dms.", time);
                        break;
                }
-               g_usleep(byte_delay_us);
+               if (len < 1)
+                       g_usleep(byte_delay_us);
        }
 
        *buflen = ibuf;
@@ -877,3 +596,56 @@ SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
 
        return SR_ERR;
 }
+
+/**
+ * Extract the serial device and options from the options linked list.
+ *
+ * @param options List of options passed from the command line.
+ * @param serial_device Pointer where to store the exctracted serial device.
+ * @param serial_options Pointer where to store the optional extracted serial
+ * options.
+ *
+ * @return SR_OK if a serial_device is found, SR_ERR if no device is found. The
+ * returned string should not be freed by the caller.
+ */
+SR_PRIV int sr_serial_extract_options(GSList *options, const char **serial_device,
+                                     const char **serial_options)
+{
+       GSList *l;
+       struct sr_config *src;
+
+       *serial_device = NULL;
+
+       for (l = options; l; l = l->next) {
+               src = l->data;
+               switch (src->key) {
+               case SR_CONF_CONN:
+                       *serial_device = g_variant_get_string(src->data, NULL);
+                       sr_dbg("Parsed serial device: %s", *serial_device);
+                       break;
+
+               case SR_CONF_SERIALCOMM:
+                       *serial_options = g_variant_get_string(src->data, NULL);
+                       sr_dbg("Parsed serial options: %s", *serial_options);
+                       break;
+               }
+       }
+
+       if (!*serial_device) {
+               sr_dbg("No serial device specified");
+               return SR_ERR;
+       }
+
+       return SR_OK;
+}
+
+SR_PRIV int serial_source_add(struct sr_serial_dev_inst *serial, int events,
+               int timeout, sr_receive_data_callback_t cb, void *cb_data)
+{
+       return sr_source_add(serial->fd, events, timeout, cb, cb_data);
+}
+
+SR_PRIV int serial_source_remove(struct sr_serial_dev_inst *serial)
+{
+       return sr_source_remove(serial->fd);
+}