diff options
Diffstat (limited to 'nuttx/drivers/mtd/skeleton.c')
| -rw-r--r-- | nuttx/drivers/mtd/skeleton.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/nuttx/drivers/mtd/skeleton.c b/nuttx/drivers/mtd/skeleton.c new file mode 100644 index 000000000..673ddadb3 --- /dev/null +++ b/nuttx/drivers/mtd/skeleton.c @@ -0,0 +1,275 @@ +/**************************************************************************** + * drivers/mtd/skeleton.c + * + * Copyright (C) 2011 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. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <sys/types.h> +#include <stdint.h> +#include <errno.h> + +#include <nuttx/fs/ioctl.h> +#include <nuttx/mtd.h> + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Types + ****************************************************************************/ + +/* This type represents the state of the MTD device. The struct mtd_dev_s + * must appear at the beginning of the definition so that you can freely + * cast between pointers to struct mtd_dev_s and struct skel_dev_s. + */ + +struct skel_dev_s +{ + struct mtd_dev_s mtd; + + /* Other implementation specific data may follow here */ +}; + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +/* MTD driver methods */ + +static int skel_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks); +static ssize_t skel_bread(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, + FAR uint8_t *buf); +static ssize_t skel_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, + FAR const uint8_t *buf); +static ssize_t skel_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes, + FAR uint8_t *buffer); +static int skel_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg); + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +static struct skel_dev_s g_skeldev = +{ + { skel_erase, skel_rbead, skel_bwrite, skel_read, skel_ioctl }, + /* Initialization of any other implemenation specific data goes here */ +}; + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: skel_erase + ****************************************************************************/ + +static int skel_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks) +{ + FAR struct skel_dev_s *priv = (FAR struct skel_dev_s *)dev; + + /* The interface definition assumes that all erase blocks ar the same size. + * If that is not true for this particular device, then transform the + * start block and nblocks as necessary. + */ + + /* Erase the specified blocks and return status (OK or a negated errno) */ + + return OK; +} + +/**************************************************************************** + * Name: skel_bread + ****************************************************************************/ + +static ssize_t skel_bread(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, + FAR uint8_t *buf) +{ + FAR struct skel_dev_s *priv = (FAR struct skel_dev_s *)dev; + + /* The interface definition assumes that all read/write blocks ar the same size. + * If that is not true for this particular device, then transform the + * start block and nblocks as necessary. + */ + + /* Read the specified blocks into the provided user buffer and return status + * (The positive, number of blocks actually read or a negated errno). + */ + + return 0; +} + +/**************************************************************************** + * Name: skel_bwrite + ****************************************************************************/ + +static ssize_t skel_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, + FAR const uint8_t *buf) +{ + FAR struct skel_dev_s *priv = (FAR struct skel_dev_s *)dev; + + /* The interface definition assumes that all read/write blocks ar the same size. + * If that is not true for this particular device, then transform the + * start block and nblocks as necessary. + */ + + /* Write the specified blocks from the provided user buffer and return status + * (The positive, number of blocks actually written or a negated errno) + */ + + return 0; +} + +/**************************************************************************** + * Name: skel_read + ****************************************************************************/ + +static ssize_t skel_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes, + FAR uint8_t *buffer) +{ + FAR struct skel_dev_s *priv = (FAR struct skel_dev_s *)dev; + + /* Some devices may support byte oriented read (optional). Byte-oriented + * writing is inherently block oriented on most MTD devices and is not supported. + * It is recommended that low-level drivers not support read() if it requires + * buffering -- let the higher level logic handle that. If the read method is + * not implemented, just set the method pointer to NULL in the struct mtd_dev_s + * instance. + */ + + /* The interface definition assumes that all read/write blocks ar the same size. + * If that is not true for this particular device, then transform the + * start block and nblocks as necessary. + */ + + /* Read the specified blocks into the provided user buffer and return status + * (The positive, number of blocks actually read or a negated errno) + */ + + return 0; +} + +/**************************************************************************** + * Name: skel_ioctl + ****************************************************************************/ + +static int skel_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg) +{ + FAR struct skel_dev_s *priv = (FAR struct skel_dev_s *)dev; + int ret = -EINVAL; /* Assume good command with bad parameters */ + + switch (cmd) + { + case MTDIOC_GEOMETRY: + { + FAR struct mtd_geometry_s *geo = (FARstruct mtd_geometry_s *)arg; + if (geo) + { + /* Populate the geometry structure with information need to know + * the capacity and how to access the device. + * + * NOTE: that the device is treated as though it where just an array + * of fixed size blocks. That is most likely not true, but the client + * will expect the device logic to do whatever is necessary to make it + * appear so. + */ + + geo->blocksize = 512; /* Size of one read/write block */ + geo->erasesize = 4096; /* Size of one erase block */ + geo->neraseblocks = 1024; /* Number of erase blocks */ + ret = OK; + } + } + break; + + case MTDIOC_XIPBASE: + { + FAR void **ppv = (FAR void**)arg; + + if (ppv) + { + /* If media is directly acccesible, return (void*) base address + * of device memory. NULL otherwise. It is acceptable to omit + * this case altogether and simply return -ENOTTY. + */ + + *ppv = NULL; + ret = OK; + } + } + break; + + case MTDIOC_BULKERASE: + { + /* Erase the entire device */ + + ret = OK; + } + break; + + default: + ret = -ENOTTY; /* Bad command */ + break; + } + + return ret; +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: skel_initialize + * + * Description: + * Create and initialize an MTD device instance. MTD devices are not + * registered in the file system, but are created as instances that can + * be bound to other functions (such as a block or character driver front + * end). + * + ****************************************************************************/ + +void skel_initialize(void) +{ + /* Perform initialization as necessary */ + + /* Return the implementation-specific state structure as the MTD device */ + + return (FAR struct mtd_dev_s *)&g_skeldev; +} |