compat: backport n_tty_ioctl_helper

This function is needed by some bluetooth drivers

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

diff --git a/compat/compat-2.6.28.c b/compat/compat-2.6.28.c
index 115bd23a719d53db4d5f3cd8556f45d3e7c90f54..bfb645a8099d2d390321d761736165323458b557 100644 (file)
--- a/compat/compat-2.6.28.c
+++ b/compat/compat-2.6.28.c
@@ -13,6 +13,8 @@
 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28))
 
 #include <linux/usb.h>
+#include <linux/tty.h>
+#include <asm/poll.h>
 
 /* 2.6.28 compat code goes here */
 
@@ -370,4 +372,130 @@ void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off,
 }
 EXPORT_SYMBOL(skb_add_rx_frag);
 
+void tty_write_unlock(struct tty_struct *tty)
+{
+       mutex_unlock(&tty->atomic_write_lock);
+       wake_up_interruptible_poll(&tty->write_wait, POLLOUT);
+}
+
+int tty_write_lock(struct tty_struct *tty, int ndelay)
+{
+       if (!mutex_trylock(&tty->atomic_write_lock)) {
+               if (ndelay)
+                       return -EAGAIN;
+               if (mutex_lock_interruptible(&tty->atomic_write_lock))
+                       return -ERESTARTSYS;
+       }
+       return 0;
+}
+
+/**
+ *     send_prio_char          -       send priority character
+ *
+ *     Send a high priority character to the tty even if stopped
+ *
+ *     Locking: none for xchar method, write ordering for write method.
+ */
+
+static int send_prio_char(struct tty_struct *tty, char ch)
+{
+       int     was_stopped = tty->stopped;
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26))
+       if (tty->ops->send_xchar) {
+               tty->ops->send_xchar(tty, ch);
+#else
+       if (tty->driver->send_xchar) {
+               tty->driver->send_xchar(tty, ch);
+#endif
+               return 0;
+       }
+
+       if (tty_write_lock(tty, 0) < 0)
+               return -ERESTARTSYS;
+
+       if (was_stopped)
+               start_tty(tty);
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26))
+       tty->ops->write(tty, &ch, 1);
+#else
+       tty->driver->write(tty, &ch, 1);
+#endif
+       if (was_stopped)
+               stop_tty(tty);
+       tty_write_unlock(tty);
+       return 0;
+}
+
+int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
+                      unsigned int cmd, unsigned long arg)
+{
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26))
+       unsigned long flags;
+#endif
+       int retval;
+
+       switch (cmd) {
+       case TCXONC:
+               retval = tty_check_change(tty);
+               if (retval)
+                       return retval;
+               switch (arg) {
+               case TCOOFF:
+                       if (!tty->flow_stopped) {
+                               tty->flow_stopped = 1;
+                               stop_tty(tty);
+                       }
+                       break;
+               case TCOON:
+                       if (tty->flow_stopped) {
+                               tty->flow_stopped = 0;
+                               start_tty(tty);
+                       }
+                       break;
+               case TCIOFF:
+                       if (STOP_CHAR(tty) != __DISABLED_CHAR)
+                               return send_prio_char(tty, STOP_CHAR(tty));
+                       break;
+               case TCION:
+                       if (START_CHAR(tty) != __DISABLED_CHAR)
+                               return send_prio_char(tty, START_CHAR(tty));
+                       break;
+               default:
+                       return -EINVAL;
+               }
+               return 0;
+       case TCFLSH:
+               return tty_perform_flush(tty, arg);
+       case TIOCPKT:
+       {
+               int pktmode;
+
+               if (tty->driver->type != TTY_DRIVER_TYPE_PTY ||
+                   tty->driver->subtype != PTY_TYPE_MASTER)
+                       return -ENOTTY;
+               if (get_user(pktmode, (int __user *) arg))
+                       return -EFAULT;
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26))
+               spin_lock_irqsave(&tty->ctrl_lock, flags);
+#endif
+               if (pktmode) {
+                       if (!tty->packet) {
+                               tty->packet = 1;
+                               tty->link->ctrl_status = 0;
+                       }
+               } else
+                       tty->packet = 0;
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26))
+               spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+#endif
+               return 0;
+       }
+       default:
+               /* Try the mode commands */
+               return tty_mode_ioctl(tty, file, cmd, arg);
+       }
+}
+EXPORT_SYMBOL(n_tty_ioctl_helper);
+
 #endif /* LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28) */

diff --git a/include/linux/compat-2.6.28.h b/include/linux/compat-2.6.28.h
index 716054888fbdd4c42dcf463ff9bcedffa3ed23ac..649fbbc3183c46306b1e41ba95cf8cb977ecb43b 100644 (file)
--- a/include/linux/compat-2.6.28.h
+++ b/include/linux/compat-2.6.28.h
@@ -230,6 +230,12 @@ unsigned long round_jiffies_up(unsigned long j);
 extern void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page,
                            int off, int size);
 
+#define wake_up_interruptible_poll(x, m)                       \
+       __wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m))
+
+extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
+                      unsigned int cmd, unsigned long arg);
+
 #endif /* (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28)) */
 
 #endif /* LINUX_26_28_COMPAT_H */