pppd: Add support for arbitrary baud rates via BOTHER on Linux (#278)

[ppp.git] / pppd / sys-linux.c

diff --git a/pppd/sys-linux.c b/pppd/sys-linux.c
index b0ad508185336785a80a156a81e9948bb5cd3cc4..c05047c765c1d6cad5e1cf38ce9897850d8a9658 100644 (file)
--- a/pppd/sys-linux.c
+++ b/pppd/sys-linux.c
@@ -104,6 +104,7 @@
 
 #if !defined(__GLIBC__) || __GLIBC__ >= 2
 #include <asm/types.h>         /* glibc 2 conflicts with linux/types.h */
+#include <asm/ioctls.h>
 #include <net/if.h>
 #include <net/if_arp.h>
 #include <net/route.h>
@@ -158,6 +159,20 @@
 #include <sys/locks.h>
 #endif
 
+#ifndef BOTHER
+#define BOTHER 0010000
+#endif
+struct termios2 {
+       unsigned int c_iflag;
+       unsigned int c_oflag;
+       unsigned int c_cflag;
+       unsigned int c_lflag;
+       unsigned char c_line;
+       unsigned char c_cc[19];
+       unsigned int c_ispeed;
+       unsigned int c_ospeed;
+};
+
 #ifdef INET6
 #ifndef _LINUX_IN6_H
 /*
@@ -898,6 +913,12 @@ struct speed {
 #ifdef B460800
     { 460800, B460800 },
 #endif
+#ifdef B500000
+    { 500000, B500000 },
+#endif
+#ifdef B576000
+    { 576000, B576000 },
+#endif
 #ifdef B921600
     { 921600, B921600 },
 #endif
@@ -942,7 +963,6 @@ static int translate_speed (int bps)
            if (bps == speedp->speed_int)
                return speedp->speed_val;
        }
-       warn("speed %d not supported", bps);
     }
     return 0;
 }
@@ -1021,26 +1041,57 @@ void set_up_tty(int tty_fd, int local)
     if (stop_bits >= 2)
        tios.c_cflag |= CSTOPB;
 
-    speed = translate_speed(inspeed);
-    if (speed) {
-       cfsetospeed (&tios, speed);
-       cfsetispeed (&tios, speed);
+    if (inspeed) {
+       speed = translate_speed(inspeed);
+       if (speed) {
+           cfsetospeed (&tios, speed);
+           cfsetispeed (&tios, speed);
+           speed = cfgetospeed(&tios);
+       }
+       baud_rate = baud_rate_of(speed);
     }
-/*
- * We can't proceed if the serial port speed is B0,
- * since that implies that the serial port is disabled.
- */
     else {
        speed = cfgetospeed(&tios);
-       if (speed == B0)
-           fatal("Baud rate for %s is 0; need explicit baud rate", devnam);
+       baud_rate = baud_rate_of(speed);
     }
 
     while (tcsetattr(tty_fd, TCSAFLUSH, &tios) < 0 && !ok_error(errno))
        if (errno != EINTR)
            fatal("tcsetattr: %m (line %d)", __LINE__);
 
-    baud_rate    = baud_rate_of(speed);
+/* Most Linux architectures and drivers support arbitrary baud rate values via BOTHER */
+#ifdef TCGETS2
+    if (!baud_rate) {
+       struct termios2 tios2;
+       if (ioctl(tty_fd, TCGETS2, &tios2) == 0) {
+           if (inspeed) {
+               tios2.c_cflag &= ~CBAUD;
+               tios2.c_cflag |= BOTHER;
+               tios2.c_ispeed = inspeed;
+               tios2.c_ospeed = inspeed;
+#ifdef TCSETS2
+               if (ioctl(tty_fd, TCSETS2, &tios2) == 0)
+                   baud_rate = inspeed;
+#endif
+           } else {
+               if ((tios2.c_cflag & CBAUD) == BOTHER && tios2.c_ospeed)
+                   baud_rate = tios2.c_ospeed;
+           }
+       }
+    }
+#endif
+
+/*
+ * We can't proceed if the serial port baud rate is unknown,
+ * since that implies that the serial port is disabled.
+ */
+    if (!baud_rate) {
+       if (inspeed)
+           fatal("speed %d not supported", inspeed);
+       else
+           fatal("Baud rate for %s is 0; need explicit baud rate", devnam);
+    }
+
     restore_term = 1;
 }