Block-to-character driver

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@1235 42af7a65-404d-4744-a932-0658087f49c3
2026-06-07 01:05:54 +08:00 · 2008-11-15 00:14:05 +00:00
parent c3edbc0eaf
commit 9f05f24615
12 changed files with 1780 additions and 0 deletions
@@ -0,0 +1,160 @@
+/****************************************************************************
+ * drivers/bch/bchlib_setup.c
+ *
+ *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Compilation Switches
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <sys/mount.h>
+
+#include <stdlib.h>
+#include <errno.h>
+#include <assert.h>
+#include <debug.h>
+
+#include <nuttx/fs.h>
+
+#include "bch_internal.h"
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: bchlib_setup
+ *
+ * Description:
+ *   Setup so that the block driver referenced by 'blkdev' can be accessed
+ *   similar to a character device.
+ *
+ ****************************************************************************/
+
+int bchlib_setup(const char *blkdev, boolean readonly, FAR void **handle)
+{
+  FAR struct bchlib_s *bch;
+  struct geometry geo;
+  int ret;
+
+  DEBUGASSERT(blkdev);
+
+  /* Allocate the BCH state structure */
+
+  bch = (FAR struct bchlib_s*)zalloc(sizeof(struct bchlib_s));
+  if (!bch)
+    {
+      fdbg("Failed to allocate BCH structure\n");
+      return -ENOMEM;
+    }
+
+  /* Open the block driver */
+
+  ret = open_blockdriver(blkdev, readonly ? MS_RDONLY : 0, &bch->inode);
+  if (ret < 0)
+    {
+      fdbg("Failed to open driver %s: %d\n", blkdev, -ret);
+      goto errout_with_bch;
+    }
+
+  DEBUGASSERT(bch->inode && bch->inode->u.i_bops && bch->inode->u.i_bops->geometry);
+
+  ret = bch->inode->u.i_bops->geometry(bch->inode, &geo);
+  if (ret < 0)
+    {
+      fdbg("geometry failed: %d\n", -ret);
+      goto errout_with_bch;
+    }
+
+  if (!geo.geo_available)
+    {
+      fdbg("geometry failed: %d\n", -ret);
+      ret = -ENODEV;
+      goto errout_with_bch;
+    }
+
+  if (!readonly && (!bch->inode->u.i_bops->write || !geo.geo_writeenabled))
+    {
+      fdbg("write access not supported\n");
+      ret = -EACCES;
+      goto errout_with_bch;
+    }
+
+  /* Save the geometry info and complete initialization of the structure */
+
+  sem_init(&bch->sem, 0, 1);
+  bch->nsectors = geo.geo_nsectors;
+  bch->sectsize = geo.geo_sectorsize;
+  bch->sector   = (size_t)-1;
+  bch->readonly = readonly;
+
+  /* Allocate the sector I/O buffer */
+
+  bch->buffer = (FAR ubyte *)malloc(bch->sectsize);
+  if (!bch->buffer)
+    {
+      fdbg("Failed to allocate sector buffer\n");
+      ret = -ENOMEM;
+      goto errout_with_bch;
+    }
+
+  *handle = bch;
+  return OK;
+
+errout_with_bch:
+  free(bch);
+  return ret;
+}