Changeset 2b86087 in rtems

Timestamp:

08/23/09 15:00:29 (13 years ago)

Author:

Joel Sherrill <joel.sherrill@…>

Branches:

4.10, 4.11, 5, master

Children:

da42259

Parents:

b8dfc88

Message:

2009-08-22 Roxana Leontie <roxana.leontie@…>

• bsp_howto/framebuffer.t: documented the improvements made to read/write

Location:

doc

Files:

• ChangeLog (modified) (1 diff)
• bsp_howto/framebuffer.t (modified) (3 diffs)

doc/ChangeLog

@@ +1 @@
+2009-08-22      Roxana Leontie <roxana.leontie@gmail.com>
+
+        * bsp_howto/framebuffer.t: documented the improvements made to
+        read/write
+
 2009-08-21      Roxana Leontie <roxana.leontie@gmail.com>
 

doc/bsp_howto/framebuffer.t

@@ -151 +151 @@
 The @code{frame_buffer_read()} is invoked from a @code{read()} operation
 on the frame buffer device.
-Read functions should allow normal and partial reading at the end of frame buffer memory,
-returning RTEMS_UNSATISFIED if trying to read beyond the frame buffer
-memory or a negative number of bytes.  
+Read functions should allow normal and partial reading at the end of frame buffer memory.  
 This method returns RTEMS_SUCCESSFUL when the device is successfully read from:
 
@@ -164 +162 @@
 )
 @{
-  /*printk( "FBVGA read called.\n" );*/
   rtems_libio_rw_args_t *rw_args = (rtems_libio_rw_args_t *)arg;
-  if ( (rw_args->offset >= fb_fix.smem_len) || (rw_args->count < 0) )@{
-     return RTEMS_UNSATISFIED;
-  @}
-  else
-  @{
-        /*partial reading*/ 
-        if ( (rw_args->offset + rw_args->count) > fb_fix.smem_len )@{
-           rw_args->count = fb_fix.smem_len - rw_args->offset; 
-           memcpy(rw_args->buffer, (const void *) (rw_args->offset + fb_fix.smem_start), rw_args->count);
-           rw_args->bytes_moved = rw_args->count;
-           return RTEMS_SUCCESSFUL;
-        @}
-        /*best reading case*/
-        else@{
-           memcpy(rw_args->buffer, (const void *) (rw_args->offset + fb_fix.smem_start), rw_args->count);
-           rw_args->bytes_moved = rw_args->count;
-           return RTEMS_SUCCESSFUL;
-        @}
-   @}      
+  rw_args->bytes_moved = ((rw_args->offset + rw_args->count) > fb_fix.smem_len ) ? (fb_fix.smem_len - rw_args->offset) : rw_args->count;
+  memcpy(rw_args->buffer, (const void *) (fb_fix.smem_start + rw_args->offset), rw_args->bytes_moved);
+  return RTEMS_SUCCESSFUL;   
 @}
 @end group
@@ -207 +188 @@
 )
 @{
-  /*printk( "FBVGA write called.\n" );*/
   rtems_libio_rw_args_t *rw_args = (rtems_libio_rw_args_t *)arg;
-  if ( (rw_args->offset >= fb_fix.smem_len) || (rw_args->count < 0) )@{
-     return RTEMS_UNSATISFIED;
-  @}
-  else
-  @{
-        /*partial writing*/
-        if ( (rw_args->offset + rw_args->count) > fb_fix.smem_len )@{
-           rw_args->count = fb_fix.smem_len - rw_args->offset; 
-           memcpy( (void *) (rw_args->offset + fb_fix.smem_start), rw_args->buffer, rw_args->count);
-           rw_args->bytes_moved = rw_args->count;
-           return RTEMS_SUCCESSFUL;
-        @}
-        /* best writing case*/
-        else@{
-           memcpy( (void *) (rw_args->offset + fb_fix.smem_start), rw_args->buffer, rw_args->count);
-           rw_args->bytes_moved = rw_args->count;
-           return RTEMS_SUCCESSFUL;
-        @}
-   @}         
+  rw_args->bytes_moved = ((rw_args->offset + rw_args->count) > fb_fix.smem_len ) ? (fb_fix.smem_len - rw_args->offset) : rw_args->count;
+  memcpy( (void *) (fb_fix.smem_start + rw_args->offset), rw_args->buffer, rw_args->bytes_moved);
+  return RTEMS_SUCCESSFUL;          
 @}
 @end group