diff options
Diffstat (limited to 'nuttx/drivers/bch/bchdev_driver.c')
-rw-r--r-- | nuttx/drivers/bch/bchdev_driver.c | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/nuttx/drivers/bch/bchdev_driver.c b/nuttx/drivers/bch/bchdev_driver.c new file mode 100644 index 000000000..262a0af46 --- /dev/null +++ b/nuttx/drivers/bch/bchdev_driver.c @@ -0,0 +1,255 @@ +/**************************************************************************** + * drivers/bch/bchdev_driver.c + * + * Copyright (C) 2008-2009 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * 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/stat.h> +#include <sys/ioctl.h> + +#include <unistd.h> +#include <string.h> +#include <fcntl.h> +#include <sched.h> +#include <errno.h> +#include <assert.h> +#include <debug.h> + +#include <nuttx/fs/fs.h> +#include <nuttx/fs/ioctl.h> + +#include "bch_internal.h" + +/**************************************************************************** + * Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +static int bch_open(FAR struct file *filp); +static int bch_close(FAR struct file *filp); +static ssize_t bch_read(FAR struct file *, FAR char *, size_t); +static ssize_t bch_write(FAR struct file *, FAR const char *, size_t); +static int bch_ioctl(FAR struct file *filp, int cmd, unsigned long arg); + +/**************************************************************************** + * Public Data + ****************************************************************************/ + +const struct file_operations bch_fops = +{ + bch_open, /* open */ + bch_close, /* close */ + bch_read, /* read */ + bch_write, /* write */ + 0, /* seek */ + bch_ioctl /* ioctl */ +#ifndef CONFIG_DISABLE_POLL + , 0 /* poll */ +#endif +}; + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: bch_open + * + * Description: Open the block device + * + ****************************************************************************/ + +static int bch_open(FAR struct file *filp) +{ + FAR struct inode *inode = filp->f_inode; + FAR struct bchlib_s *bch; + + DEBUGASSERT(inode && inode->i_private); + bch = (FAR struct bchlib_s *)inode->i_private; + + /* Increment the reference count */ + + bchlib_semtake(bch); + if (bch->refs == MAX_OPENCNT) + { + return -EMFILE; + } + else + { + bch->refs++; + } + bchlib_semgive(bch); + + return OK; +} + +/**************************************************************************** + * Name: bch_close + * + * Description: close the block device + * + ****************************************************************************/ + +static int bch_close(FAR struct file *filp) +{ + FAR struct inode *inode = filp->f_inode; + FAR struct bchlib_s *bch; + int ret = OK; + + DEBUGASSERT(inode && inode->i_private); + bch = (FAR struct bchlib_s *)inode->i_private; + + /* Flush any dirty pages remaining in the cache */ + + bchlib_semtake(bch); + (void)bchlib_flushsector(bch); + + /* Decrement the reference count (I don't use bchlib_decref() because I + * want the entire close operation to be atomic wrt other driver operations. + */ + + if (bch->refs == 0) + { + ret = -EIO; + } + else + { + bch->refs--; + } + bchlib_semgive(bch); + + return ret; +} + +/**************************************************************************** + * Name:bch_read + ****************************************************************************/ + +static ssize_t bch_read(FAR struct file *filp, FAR char *buffer, size_t len) +{ + FAR struct inode *inode = filp->f_inode; + FAR struct bchlib_s *bch; + int ret; + + DEBUGASSERT(inode && inode->i_private); + bch = (FAR struct bchlib_s *)inode->i_private; + + bchlib_semtake(bch); + ret = bchlib_read(bch, buffer, filp->f_pos, len); + if (ret > 0) + { + filp->f_pos += len; + } + bchlib_semgive(bch); + return ret; +} + +/**************************************************************************** + * Name:bch_write + ****************************************************************************/ + +static ssize_t bch_write(FAR struct file *filp, FAR const char *buffer, size_t len) +{ + FAR struct inode *inode = filp->f_inode; + FAR struct bchlib_s *bch; + int ret = -EACCES; + + DEBUGASSERT(inode && inode->i_private); + bch = (FAR struct bchlib_s *)inode->i_private; + + if (!bch->readonly) + { + bchlib_semtake(bch); + ret = bchlib_write(bch, buffer, filp->f_pos, len); + if (ret > 0) + { + filp->f_pos += len; + } + bchlib_semgive(bch); + } + + return ret; +} + +/**************************************************************************** + * Name: bch_ioctl + * + * Description: Return device geometry + * + ****************************************************************************/ + +static int bch_ioctl(FAR struct file *filp, int cmd, unsigned long arg) +{ + FAR struct inode *inode = filp->f_inode; + FAR struct bchlib_s *bch; + int ret = -ENOTTY; + + DEBUGASSERT(inode && inode->i_private); + bch = (FAR struct bchlib_s *)inode->i_private; + + if (cmd == DIOC_GETPRIV) + { + FAR struct bchlib_s **bchr = (FAR struct bchlib_s **)((uintptr_t)arg); + + bchlib_semtake(bch); + if (!bchr && bch->refs < 255) + { + ret = -EINVAL; + } + else + { + bch->refs++; + *bchr = bch; + } + bchlib_semgive(bch); + } + + return ret; +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ |