termios: Partially hide rtems_termios_tty

Move interrupt lock to device context and expose only this structure to
the read, write and set attributes device handler.  This makes these
device handler independent of the general Termios infrastructure
suitable for direct use in printk() support.

1 files changed, 90 insertions, 52 deletions

diff --git a/cpukit/libcsupport/src/termios.c b/cpukit/libcsupport/src/termios.c
index 6119b22a55..f0ecad0130 100644
--- a/cpukit/libcsupport/src/termios.c
+++ b/cpukit/libcsupport/src/termios.c
@@ -134,7 +134,7 @@ rtems_status_code rtems_termios_device_install(
   rtems_device_minor_number           minor,
   const rtems_termios_device_handler *handler,
   const rtems_termios_device_flow    *flow,
-  void                               *context
+  rtems_termios_device_context       *context
 )
 {
   rtems_status_code          sc;
@@ -227,12 +227,23 @@ rtems_status_code rtems_termios_device_remove(
   return RTEMS_SUCCESSFUL;
 }
 
+static rtems_termios_tty *
+legacyContextToTTY (rtems_termios_device_context *ctx)
+{
+  return RTEMS_CONTAINER_OF (ctx, rtems_termios_tty, legacy_device_context);
+}
+
 static bool
 rtems_termios_callback_firstOpen(
   rtems_termios_tty             *tty,
+  rtems_termios_device_context  *ctx,
+  struct termios                *term,
   rtems_libio_open_close_args_t *args
 )
 {
+  (void) ctx;
+  (void) term;
+
   (*tty->device.firstOpen) (tty->major, tty->minor, args);
 
   return true;
@@ -241,48 +252,61 @@ rtems_termios_callback_firstOpen(
 static void
 rtems_termios_callback_lastClose(
   rtems_termios_tty             *tty,
+  rtems_termios_device_context  *ctx,
   rtems_libio_open_close_args_t *args
 )
 {
+  (void) ctx;
+
   (*tty->device.lastClose) (tty->major, tty->minor, args);
 }
 
 static int
-rtems_termios_callback_pollRead (struct rtems_termios_tty *tty)
+rtems_termios_callback_pollRead (rtems_termios_device_context *ctx)
 {
+  rtems_termios_tty *tty = legacyContextToTTY (ctx);
+
   return (*tty->device.pollRead) (tty->minor);
 }
 
 static void
 rtems_termios_callback_write(
-  rtems_termios_tty *tty,
-  const char        *buf,
-  size_t             len
+  rtems_termios_device_context *ctx,
+  const char                   *buf,
+  size_t                        len
 )
 {
+  rtems_termios_tty *tty = legacyContextToTTY (ctx);
+
   (*tty->device.write) (tty->minor, buf, len);
 }
 
 static bool
 rtems_termios_callback_setAttributes(
-  rtems_termios_tty    *tty,
-  const struct termios *term
+  rtems_termios_device_context *ctx,
+  const struct termios         *term
 )
 {
+  rtems_termios_tty *tty = legacyContextToTTY (ctx);
+
   (*tty->device.setAttributes) (tty->minor, term);
 
   return true;
 }
 
 static void
-rtems_termios_callback_stopRemoteTx (rtems_termios_tty *tty)
+rtems_termios_callback_stopRemoteTx (rtems_termios_device_context *ctx)
 {
+  rtems_termios_tty *tty = legacyContextToTTY (ctx);
+
   (*tty->device.stopRemoteTx) (tty->minor);
 }
 
 static void
-rtems_termios_callback_startRemoteTx (rtems_termios_tty *tty)
+rtems_termios_callback_startRemoteTx (rtems_termios_device_context *ctx)
 {
+  rtems_termios_tty *tty = legacyContextToTTY (ctx);
+
   (*tty->device.startRemoteTx) (tty->minor);
 }
 
@@ -292,21 +316,22 @@ rtems_termios_callback_startRemoteTx (rtems_termios_tty *tty)
 static void
 drainOutput (struct rtems_termios_tty *tty)
 {
+  rtems_termios_device_context *ctx = tty->device_context;
   rtems_interrupt_lock_context lock_context;
   rtems_status_code sc;
 
   if (tty->handler.mode != TERMIOS_POLLED) {
-    rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+    rtems_termios_device_lock_acquire (ctx, &lock_context);
     while (tty->rawOutBuf.Tail != tty->rawOutBuf.Head) {
       tty->rawOutBufState = rob_wait;
-      rtems_termios_interrupt_lock_release (tty, &lock_context);
+      rtems_termios_device_lock_release (ctx, &lock_context);
       sc = rtems_semaphore_obtain(
         tty->rawOutBuf.Semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
       if (sc != RTEMS_SUCCESSFUL)
         rtems_fatal_error_occurred (sc);
-      rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+      rtems_termios_device_lock_acquire (ctx, &lock_context);
     }
-    rtems_termios_interrupt_lock_release (tty, &lock_context);
+    rtems_termios_device_lock_release (ctx, &lock_context);
   }
 }
 
@@ -344,7 +369,7 @@ rtems_termios_destroy_tty (rtems_termios_tty *tty, void *arg, bool last_close)
       rtems_fatal_error_occurred (sc);
   }
   if (last_close && tty->handler.last_close)
-     (*tty->handler.last_close)(tty, arg);
+     (*tty->handler.last_close)(tty, tty->device_context, arg);
 
   if (tty->device_node != NULL)
     tty->device_node->tty = NULL;
@@ -355,7 +380,10 @@ rtems_termios_destroy_tty (rtems_termios_tty *tty, void *arg, bool last_close)
   if ((tty->handler.poll_read == NULL) ||
       (tty->handler.mode == TERMIOS_TASK_DRIVEN))
     rtems_semaphore_delete (tty->rawInBuf.Semaphore);
-  rtems_interrupt_lock_destroy (&tty->interrupt_lock);
+
+  if (tty->device_context == &tty->legacy_device_context)
+    rtems_interrupt_lock_destroy (&tty->legacy_device_context.interrupt_lock);
+
   free (tty->rawInBuf.theBuf);
   free (tty->rawOutBuf.theBuf);
   free (tty->cbuf);
@@ -489,7 +517,10 @@ rtems_termios_open_tty(
       tty->device = *callbacks;
     }
 
-    rtems_interrupt_lock_initialize (&tty->interrupt_lock, "Termios");
+    if (tty->device_context == NULL) {
+      tty->device_context = &tty->legacy_device_context;
+      rtems_termios_device_context_initialize (tty->device_context, "Termios");
+    }
 
     /*
      * Create I/O tasks
@@ -569,8 +600,8 @@ rtems_termios_open_tty(
   }
   args->iop->data1 = tty;
   if (!tty->refcount++) {
-    if (tty->handler.first_open &&
-        !(*tty->handler.first_open)(tty, args)) {
+    if (tty->handler.first_open && !(*tty->handler.first_open)(
+        tty, tty->device_context, &tty->termios, args)) {
       rtems_termios_destroy_tty(tty, args, false);
       return NULL;
     }
@@ -683,24 +714,26 @@ rtems_termios_open (
 static void
 flushOutput (struct rtems_termios_tty *tty)
 {
+  rtems_termios_device_context *ctx = tty->device_context;
   rtems_interrupt_lock_context lock_context;
 
-  rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+  rtems_termios_device_lock_acquire (ctx, &lock_context);
   tty->rawOutBuf.Tail = 0;
   tty->rawOutBuf.Head = 0;
   tty->rawOutBufState = rob_idle;
-  rtems_termios_interrupt_lock_release (tty, &lock_context);
+  rtems_termios_device_lock_release (ctx, &lock_context);
 }
 
 static void
 flushInput (struct rtems_termios_tty *tty)
 {
+  rtems_termios_device_context *ctx = tty->device_context;
   rtems_interrupt_lock_context lock_context;
 
-  rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+  rtems_termios_device_lock_acquire (ctx, &lock_context);
   tty->rawInBuf.Tail = 0;
   tty->rawInBuf.Head = 0;
-  rtems_termios_interrupt_lock_release (tty, &lock_context);
+  rtems_termios_device_lock_release (ctx, &lock_context);
 }
 
 static void
@@ -784,6 +817,7 @@ rtems_status_code rtems_termios_bufsize (
 static void
 termios_set_flowctrl(struct rtems_termios_tty *tty)
 {
+  rtems_termios_device_context *ctx = tty->device_context;
   rtems_interrupt_lock_context lock_context;
   /*
    * check for flow control options to be switched off
@@ -798,16 +832,16 @@ termios_set_flowctrl(struct rtems_termios_tty *tty)
     /* has output been stopped due to received XOFF? */
     if (tty->flow_ctrl & FL_OSTOP) {
       /* disable interrupts    */
-      rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+      rtems_termios_device_lock_acquire (ctx, &lock_context);
       tty->flow_ctrl &= ~FL_OSTOP;
       /* check for chars in output buffer (or rob_state?) */
       if (tty->rawOutBufState != rob_idle) {
         /* if chars available, call write function... */
         (*tty->handler.write)(
-          tty, &tty->rawOutBuf.theBuf[tty->rawOutBuf.Tail],1);
+          ctx, &tty->rawOutBuf.theBuf[tty->rawOutBuf.Tail],1);
       }
       /* reenable interrupts */
-      rtems_termios_interrupt_lock_release (tty, &lock_context);
+      rtems_termios_device_lock_release (ctx, &lock_context);
     }
   }
   /* check for incoming XON/XOFF flow control switched off */
@@ -826,7 +860,7 @@ termios_set_flowctrl(struct rtems_termios_tty *tty)
     /* restart remote Tx, if it was stopped */
     if ((tty->flow_ctrl & FL_IRTSOFF) &&
         (tty->flow.start_remote_tx != NULL)) {
-      tty->flow.start_remote_tx(tty);
+      tty->flow.start_remote_tx(ctx);
     }
     tty->flow_ctrl &= ~(FL_IRTSOFF);
   }
@@ -906,7 +940,7 @@ rtems_termios_ioctl (void *arg)
       }
     }
     if (tty->handler.set_attributes) {
-      sc = (*tty->handler.set_attributes)(tty, &tty->termios) ?
+      sc = (*tty->handler.set_attributes)(tty->device_context, &tty->termios) ?
         RTEMS_SUCCESSFUL : RTEMS_IO_ERROR;
     }
     break;
@@ -1003,7 +1037,7 @@ startXmit (
     nToSend = 0;
     /* stop transmitter */
     if (transmitting) {
-      (*tty->handler.write) (tty, NULL, 0);
+      (*tty->handler.write) (tty->device_context, NULL, 0);
     }
   } else {
     /* when flow control XON or XOF, don't send blocks of data     */
@@ -1017,7 +1051,7 @@ startXmit (
       nToSend = tty->rawOutBuf.Head - newTail;
 
     (*tty->handler.write)(
-        tty, &tty->rawOutBuf.theBuf[newTail], nToSend);
+        tty->device_context, &tty->rawOutBuf.theBuf[newTail], nToSend);
   }
 
   return nToSend;
@@ -1032,11 +1066,12 @@ rtems_termios_puts (
 {
   const char *buf = _buf;
   unsigned int newHead;
+  rtems_termios_device_context *ctx = tty->device_context;
   rtems_interrupt_lock_context lock_context;
   rtems_status_code sc;
 
   if (tty->handler.mode == TERMIOS_POLLED) {
-    (*tty->handler.write)(tty, buf, len);
+    (*tty->handler.write)(ctx, buf, len);
     return;
   }
 
@@ -1049,15 +1084,15 @@ rtems_termios_puts (
     if (newHead >= tty->rawOutBuf.Size)
       newHead -= tty->rawOutBuf.Size;
 
-    rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+    rtems_termios_device_lock_acquire (ctx, &lock_context);
     while (newHead == tty->rawOutBuf.Tail) {
       tty->rawOutBufState = rob_wait;
-      rtems_termios_interrupt_lock_release (tty, &lock_context);
+      rtems_termios_device_lock_release (ctx, &lock_context);
       sc = rtems_semaphore_obtain(
         tty->rawOutBuf.Semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
       if (sc != RTEMS_SUCCESSFUL)
         rtems_fatal_error_occurred (sc);
-      rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+      rtems_termios_device_lock_acquire (ctx, &lock_context);
     }
 
     /* Determine free space up to current tail or end of ring buffer */
@@ -1090,7 +1125,7 @@ rtems_termios_puts (
       startXmit (tty, tty->rawOutBuf.Tail, false);
     }
 
-    rtems_termios_interrupt_lock_release (tty, &lock_context);
+    rtems_termios_device_lock_release (ctx, &lock_context);
 
     buf += nToCopy;
     len -= nToCopy;
@@ -1371,7 +1406,7 @@ fillBufferPoll (struct rtems_termios_tty *tty)
 
   if (tty->termios.c_lflag & ICANON) {
     for (;;) {
-      n = (*tty->handler.poll_read)(tty);
+      n = (*tty->handler.poll_read)(tty->device_context);
       if (n < 0) {
         rtems_task_wake_after (1);
       } else {
@@ -1384,7 +1419,7 @@ fillBufferPoll (struct rtems_termios_tty *tty)
 
     then = rtems_clock_get_ticks_since_boot();
     for (;;) {
-      n = (*tty->handler.poll_read)(tty);
+      n = (*tty->handler.poll_read)(tty->device_context);
       if (n < 0) {
         if (tty->termios.c_cc[VMIN]) {
           if (tty->termios.c_cc[VTIME] && tty->ccount) {
@@ -1447,12 +1482,12 @@ fillBufferQueue (struct rtems_termios_tty *tty)
           || (tty->flow_ctrl & FL_OSTOP))) {
           /* XON should be sent now... */
           (*tty->handler.write)(
-            tty, (void *)&(tty->termios.c_cc[VSTART]), 1);
+            tty->device_context, (void *)&(tty->termios.c_cc[VSTART]), 1);
         } else if (tty->flow_ctrl & FL_MDRTS) {
           tty->flow_ctrl &= ~FL_IRTSOFF;
           /* activate RTS line */
           if (tty->flow.start_remote_tx != NULL) {
-            tty->flow.start_remote_tx(tty);
+            tty->flow.start_remote_tx(tty->device_context);
           }
         }
       }
@@ -1550,6 +1585,7 @@ rtems_termios_enqueue_raw_characters (void *ttyp, const char *buf, int len)
   char c;
   int dropped = 0;
   bool flow_rcv = false; /* true, if flow control char received */
+  rtems_termios_device_context *ctx = tty->device_context;
   rtems_interrupt_lock_context lock_context;
 
   if (rtems_termios_linesw[tty->t_line].l_rint != NULL) {
@@ -1598,21 +1634,21 @@ rtems_termios_enqueue_raw_characters (void *ttyp, const char *buf, int len)
       /* restart output according to FL_ORCVXOF flag */
       if ((tty->flow_ctrl & (FL_ORCVXOF | FL_OSTOP)) == FL_OSTOP) {
         /* disable interrupts    */
-        rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+        rtems_termios_device_lock_acquire (ctx, &lock_context);
         tty->flow_ctrl &= ~FL_OSTOP;
         /* check for chars in output buffer (or rob_state?) */
         if (tty->rawOutBufState != rob_idle) {
           /* if chars available, call write function... */
           (*tty->handler.write)(
-            tty, &tty->rawOutBuf.theBuf[tty->rawOutBuf.Tail], 1);
+            ctx, &tty->rawOutBuf.theBuf[tty->rawOutBuf.Tail], 1);
         }
         /* reenable interrupts */
-        rtems_termios_interrupt_lock_release (tty, &lock_context);
+        rtems_termios_device_lock_release (ctx, &lock_context);
       }
     } else {
       newTail = (tty->rawInBuf.Tail + 1) % tty->rawInBuf.Size;
       /* if chars_in_buffer > highwater                */
-      rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+      rtems_termios_device_lock_acquire (ctx, &lock_context);
       if ((((newTail - tty->rawInBuf.Head + tty->rawInBuf.Size)
             % tty->rawInBuf.Size) > tty->highwater) &&
           !(tty->flow_ctrl & FL_IREQXOF)) {
@@ -1625,20 +1661,20 @@ rtems_termios_enqueue_raw_characters (void *ttyp, const char *buf, int len)
             /* if tx is stopped due to XOFF or out of data */
             /*    call write function here                 */
             tty->flow_ctrl |= FL_ISNTXOF;
-            (*tty->handler.write)(tty,
+            (*tty->handler.write)(ctx,
                 (void *)&(tty->termios.c_cc[VSTOP]), 1);
           }
         } else if ((tty->flow_ctrl & (FL_MDRTS | FL_IRTSOFF)) == (FL_MDRTS) ) {
           tty->flow_ctrl |= FL_IRTSOFF;
           /* deactivate RTS line */
           if (tty->flow.stop_remote_tx != NULL) {
-            tty->flow.stop_remote_tx(tty);
+            tty->flow.stop_remote_tx(ctx);
           }
         }
       }
 
       /* reenable interrupts */
-      rtems_termios_interrupt_lock_release (tty, &lock_context);
+      rtems_termios_device_lock_release (ctx, &lock_context);
 
       if (newTail == tty->rawInBuf.Head) {
         dropped++;
@@ -1672,16 +1708,17 @@ rtems_termios_refill_transmitter (struct rtems_termios_tty *tty)
   bool wakeUpWriterTask = false;
   unsigned int newTail;
   int nToSend;
+  rtems_termios_device_context *ctx = tty->device_context;
   rtems_interrupt_lock_context lock_context;
   int len;
 
-  rtems_termios_interrupt_lock_acquire (tty, &lock_context);
+  rtems_termios_device_lock_acquire (ctx, &lock_context);
 
   /* check for XOF/XON to send */
   if ((tty->flow_ctrl & (FL_MDXOF | FL_IREQXOF | FL_ISNTXOF))
       == (FL_MDXOF | FL_IREQXOF)) {
     /* XOFF should be sent now... */
-    (*tty->handler.write)(tty, (void *)&(tty->termios.c_cc[VSTOP]), 1);
+    (*tty->handler.write)(ctx, (void *)&(tty->termios.c_cc[VSTOP]), 1);
 
     tty->t_dqlen--;
     tty->flow_ctrl |= FL_ISNTXOF;
@@ -1697,7 +1734,7 @@ rtems_termios_refill_transmitter (struct rtems_termios_tty *tty)
      * buffer, although the corresponding data is not yet out!
      * Therefore the dequeue "length" should be reduced by 1
      */
-    (*tty->handler.write)(tty, (void *)&(tty->termios.c_cc[VSTART]), 1);
+    (*tty->handler.write)(ctx, (void *)&(tty->termios.c_cc[VSTART]), 1);
 
     tty->t_dqlen--;
     tty->flow_ctrl &= ~FL_ISNTXOF;
@@ -1714,7 +1751,7 @@ rtems_termios_refill_transmitter (struct rtems_termios_tty *tty)
       wakeUpWriterTask = true;
     }
 
-    (*tty->handler.write) (tty, NULL, 0);
+    (*tty->handler.write) (ctx, NULL, 0);
     nToSend = 0;
   } else {
     len = tty->t_dqlen;
@@ -1734,7 +1771,7 @@ rtems_termios_refill_transmitter (struct rtems_termios_tty *tty)
        * Buffer has become empty
        */
       tty->rawOutBufState = rob_idle;
-      (*tty->handler.write) (tty, NULL, 0);
+      (*tty->handler.write) (ctx, NULL, 0);
       nToSend = 0;
 
       /*
@@ -1751,7 +1788,7 @@ rtems_termios_refill_transmitter (struct rtems_termios_tty *tty)
     }
   }
 
-  rtems_termios_interrupt_lock_release (tty, &lock_context);
+  rtems_termios_device_lock_release (ctx, &lock_context);
 
   if (wakeUpWriterTask) {
     rtems_semaphore_release (tty->rawOutBuf.Semaphore);
@@ -1854,6 +1891,7 @@ static rtems_task rtems_termios_txdaemon(rtems_task_argument argument)
 static rtems_task rtems_termios_rxdaemon(rtems_task_argument argument)
 {
   struct rtems_termios_tty *tty = (struct rtems_termios_tty *)argument;
+  rtems_termios_device_context *ctx = tty->device_context;
   rtems_event_set the_event;
   int c;
   char c_buf;
@@ -1876,7 +1914,7 @@ static rtems_task rtems_termios_rxdaemon(rtems_task_argument argument)
     /*
      * do something
      */
-    c = tty->handler.poll_read(tty);
+    c = tty->handler.poll_read(ctx);
     if (c != EOF) {
       /*
        * poll_read did call enqueue on its own