diff options
author | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2011-11-01 13:08:19 +0000 |
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committer | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2011-11-01 13:08:19 +0000 |
commit | 53c07074863863faa8209e16c11240d02e0ec745 (patch) | |
tree | f664af4c84bf1eeee182afea0e8cb4e087b81511 /nuttx/drivers/mtd | |
parent | aca0035de6e6039f03b4954cdb6187267e1917d9 (diff) | |
download | px4-nuttx-53c07074863863faa8209e16c11240d02e0ec745.tar.gz px4-nuttx-53c07074863863faa8209e16c11240d02e0ec745.tar.bz2 px4-nuttx-53c07074863863faa8209e16c11240d02e0ec745.zip |
Add support for configurable block size on AT24 EEPROM driver
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4076 42af7a65-404d-4744-a932-0658087f49c3
Diffstat (limited to 'nuttx/drivers/mtd')
-rw-r--r-- | nuttx/drivers/mtd/at24xx.c | 777 |
1 files changed, 428 insertions, 349 deletions
diff --git a/nuttx/drivers/mtd/at24xx.c b/nuttx/drivers/mtd/at24xx.c index 2aa116d83..50a6ab913 100644 --- a/nuttx/drivers/mtd/at24xx.c +++ b/nuttx/drivers/mtd/at24xx.c @@ -1,349 +1,428 @@ -/************************************************************************************
- * drivers/mtd/at24xx.c
- * Driver for I2C-based at24cxx EEPROM(at24c32,at24c64,at24c128,at24c256)
- *
- * Copyright (C) 2011 Li Zhuoyi. All rights reserved.
- * Author: Li Zhuoyi <lzyy.cn@gmail.com>
- * History: 0.1 2011-08-20 initial version
- *
- * Derived from drivers/mtd/m25px.c
- *
- * Copyright (C) 2009-2011 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 <stdbool.h>
-#include <stdlib.h>
-#include <errno.h>
-#include <debug.h>
-
-#include <nuttx/kmalloc.h>
-#include <nuttx/ioctl.h>
-#include <nuttx/i2c.h>
-#include <nuttx/mtd.h>
-
-#ifdef CONFIG_MTD_AT24XX
-
-/************************************************************************************
- * Pre-processor Definitions
- ************************************************************************************/
-#ifndef CONFIG_AT24XX_SIZE
-#define CONFIG_AT24XX_SIZE 64
-#endif
-#ifndef CONFIG_AT24XX_ADDR
-#define CONFIG_AT24XX_ADDR 0x50
-#endif
-
-#if CONFIG_AT24XX_SIZE == 32
-#define AT24XX_NPAGES 128
-#define AT24XX_PAGESIZE 32
-#elif CONFIG_AT24XX_SIZE == 64
-#define AT24XX_NPAGES 256
-#define AT24XX_PAGESIZE 32
-#elif CONFIG_AT24XX_SIZE == 128
-#define AT24XX_NPAGES 256
-#define AT24XX_PAGESIZE 64
-#elif CONFIG_AT24XX_SIZE == 256
-#define AT24XX_NPAGES 512
-#define AT24XX_PAGESIZE 64
-#endif
-
-/************************************************************************************
- * 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 at24c_dev_s.
- */
-
-struct at24c_dev_s
-{
- struct mtd_dev_s mtd; /* MTD interface */
- FAR struct i2c_dev_s *dev; /* Saved I2C interface instance */
- uint8_t addr;
- uint16_t pagesize; /* 32,63 */
- uint16_t npages; /* 128,256,512,1024 */
-};
-
-/************************************************************************************
- * Private Function Prototypes
- ************************************************************************************/
-
-/* MTD driver methods */
-
-static int at24c_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks);
-static ssize_t at24c_bread(FAR struct mtd_dev_s *dev, off_t startblock,size_t nblocks, FAR uint8_t *buf);
-static ssize_t at24c_bwrite(FAR struct mtd_dev_s *dev, off_t startblock,size_t nblocks, FAR const uint8_t *buf);
-static ssize_t at24c_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes,FAR uint8_t *buffer);
-static int at24c_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg);
-
-/************************************************************************************
- * Private Data
- ************************************************************************************/
-static struct at24c_dev_s g_at24c =
-{
- .addr = CONFIG_AT24XX_ADDR,
- .pagesize = AT24XX_PAGESIZE,
- .npages = AT24XX_NPAGES,
-};
-
-/************************************************************************************
- * Private Functions
- ************************************************************************************/
-
-static int at24c_eraseall(FAR struct at24c_dev_s *priv)
-{
- int blocksleft = priv->pagesize;
- int startblock = 0;
- uint8_t buf[66];
- memset(&buf[2],0xff,priv->pagesize);
- I2C_SETADDRESS(priv->dev,priv->addr,7);
- I2C_SETFREQUENCY(priv->dev,100000);
- while (blocksleft-- > 0)
- {
- uint16_t offset=startblock*priv->pagesize;
- buf[1]=offset&0xff;
- buf[0]=(offset>>8)&0xff;
-
- while (I2C_WRITE(priv->dev,buf,2)<0)
- {
- usleep(1000);
- }
- I2C_WRITE(priv->dev, buf, priv->pagesize+2);
- startblock++;
- }
- return OK;
-}
-
-/************************************************************************************
- * Name: at24c_erase
- ************************************************************************************/
-
-static int at24c_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks)
-{
- /*
- * EEprom need not erase
- */
- return (int)nblocks;
-}
-
-/************************************************************************************
- * Name: at24c_bread
- ************************************************************************************/
-
-static ssize_t at24c_bread(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks,
- FAR uint8_t *buffer)
-{
- FAR struct at24c_dev_s *priv = (FAR struct at24c_dev_s *)dev;
- size_t blocksleft = nblocks;
-
- fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
-
- if (startblock >= priv->npages)
- {
- return 0;
- }
-
- if (startblock + nblocks > priv->npages)
- {
- nblocks = priv->npages - startblock;
- }
-
- I2C_SETADDRESS(priv->dev,priv->addr,7);
- I2C_SETFREQUENCY(priv->dev,100000);
- int tail;
- while (blocksleft-- > 0)
- {
- uint16_t offset=startblock*priv->pagesize;
- uint8_t buf[2];
- buf[1]=offset&0xff;
- buf[0]=(offset>>8)&0xff;
- while (I2C_WRITE(priv->dev,buf,2)<0)
- {
- fvdbg("wait\n");
- usleep(1000);
- }
- I2C_READ(priv->dev, buffer,priv->pagesize);
- startblock++;
- buffer+=priv->pagesize;
- }
- return nblocks;
-}
-
-/************************************************************************************
- * Name: at24c_bwrite
- ************************************************************************************/
-
-static ssize_t at24c_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks,
- FAR const uint8_t *buffer)
-{
- FAR struct at24c_dev_s *priv = (FAR struct at24c_dev_s *)dev;
- size_t blocksleft = nblocks;
- uint8_t buf[66];
-
- if (startblock >= priv->npages)
- {
- return 0;
- }
-
- if (startblock + nblocks > priv->npages)
- {
- nblocks = priv->npages - startblock;
- }
-
-
- fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
- I2C_SETADDRESS(priv->dev,priv->addr,7);
- I2C_SETFREQUENCY(priv->dev,100000);
- while (blocksleft-- > 0)
- {
- uint16_t offset=startblock*priv->pagesize;
- while (I2C_WRITE(priv->dev,(uint8_t *)&offset,2)<0)
- {
- fvdbg("wait\n");
- usleep(1000);
- }
- buf[1]=offset&0xff;
- buf[0]=(offset>>8)&0xff;
- memcpy(&buf[2],buffer,priv->pagesize);
-
- I2C_WRITE(priv->dev, buf, priv->pagesize+2);
- startblock++;
- buffer+=priv->pagesize;
- }
- return nblocks;
-}
-
-/************************************************************************************
- * Name: at24c_ioctl
- ************************************************************************************/
-
-static int at24c_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg)
-{
- FAR struct at24c_dev_s *priv = (FAR struct at24c_dev_s *)dev;
- int ret = -EINVAL; /* Assume good command with bad parameters */
-
- fvdbg("cmd: %d \n", cmd);
-
- switch (cmd)
- {
- case MTDIOC_GEOMETRY:
- {
- FAR struct mtd_geometry_s *geo = (FAR struct mtd_geometry_s *)((uintptr_t)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 = priv->pagesize;
- geo->erasesize = priv->pagesize;
- geo->neraseblocks = priv->npages;
- ret = OK;
-
- fvdbg("blocksize: %d erasesize: %d neraseblocks: %d\n",
- geo->blocksize, geo->erasesize, geo->neraseblocks);
- }
- }
- break;
-
- case MTDIOC_BULKERASE:
- ret=at24c_eraseall(priv);
- break;
-
- case MTDIOC_XIPBASE:
- default:
- ret = -ENOTTY; /* Bad command */
- break;
- }
-
- return ret;
-}
-
-/************************************************************************************
- * Public Functions
- ************************************************************************************/
-
-/************************************************************************************
- * Name: at24c_initialize
- *
- * Description:
- * Create an initialize 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).
- *
- ************************************************************************************/
-
-FAR struct mtd_dev_s *at24c_initialize(FAR struct i2c_dev_s *dev)
-{
- FAR struct at24c_dev_s *priv;
- int ret;
-
- fvdbg("dev: %p\n", dev);
-
- /* Allocate a state structure (we allocate the structure instead of using
- * a fixed, static allocation so that we can handle multiple FLASH devices.
- * The current implementation would handle only one FLASH part per SPI
- * device (only because of the SPIDEV_FLASH definition) and so would have
- * to be extended to handle multiple FLASH parts on the same SPI bus.
- */
-
- priv = &g_at24c;
- if (priv)
- {
- /* Initialize the allocated structure */
-
- priv->mtd.erase = at24c_erase;
- priv->mtd.bread = at24c_bread;
- priv->mtd.bwrite = at24c_bwrite;
- priv->mtd.ioctl = at24c_ioctl;
- priv->dev = dev;
- }
- /* Return the implementation-specific state structure as the MTD device */
- fvdbg("Return %p\n", priv);
- return (FAR struct mtd_dev_s *)priv;
-}
-
-#endif
+/************************************************************************************ + * drivers/mtd/at24xx.c + * Driver for I2C-based at24cxx EEPROM(at24c32,at24c64,at24c128,at24c256) + * + * Copyright (C) 2011 Li Zhuoyi. All rights reserved. + * Author: Li Zhuoyi <lzyy.cn@gmail.com> + * History: 0.1 2011-08-20 initial version + * + * 2011-11-1 Added support for larger MTD block sizes: Hal Glenn <hglenn@2g-eng.com> + * + * Derived from drivers/mtd/m25px.c + * + * Copyright (C) 2009-2011 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. + * + ************************************************************************************/ + +/************************************************************************************ + * Included Files + ************************************************************************************/ + +#include <nuttx/config.h> + +#include <sys/types.h> +#include <stdint.h> +#include <stdbool.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include <errno.h> +#include <debug.h> + +#include <nuttx/kmalloc.h> +#include <nuttx/ioctl.h> +#include <nuttx/i2c.h> +#include <nuttx/mtd.h> + +#ifdef CONFIG_MTD_AT24XX + +/************************************************************************************ + * Pre-processor Definitions + ************************************************************************************/ + +/* As a minimum, the size of the AT24 part and its 7-bit I2C address are required. */ + +#ifndef CONFIG_AT24XX_SIZE +# warning "Assuming AT24 size 64" +# define CONFIG_AT24XX_SIZE 64 +#endif +#ifndef CONFIG_AT24XX_ADDR +# warning "Assuming AT24 address of 0x50" +# define CONFIG_AT24XX_ADDR 0x50 +#endif + +/* Get the part configuration based on the size configuration */ + +#if CONFIG_AT24XX_SIZE == 32 +# define AT24XX_NPAGES 128 +# define AT24XX_PAGESIZE 32 +#elif CONFIG_AT24XX_SIZE == 48 +# define AT24XX_NPAGES 192 +# define AT24XX_PAGESIZE 32 +#elif CONFIG_AT24XX_SIZE == 64 +# define AT24XX_NPAGES 256 +# define AT24XX_PAGESIZE 32 +#elif CONFIG_AT24XX_SIZE == 128 +# define AT24XX_NPAGES 256 +# define AT24XX_PAGESIZE 64 +#elif CONFIG_AT24XX_SIZE == 256 +# define AT24XX_NPAGES 512 +# define AT24XX_PAGESIZE 64 +#endif + +/* For applications where a file system is used on the AT24, the tiny page sizes + * will result in very inefficient FLASH usage. In such cases, it is better if + * blocks are comprised of "clusters" of pages so that the file system block + * size is, say, 256 or 512 bytes. In any event, the block size *must* be an + * even multiple of the pages. + */ + +#ifndef CONFIG_AT24XX_MTD_BLOCKSIZE +# warning "Assuming driver block size is the same as the FLASH page size" +# define CONFIG_AT24XX_MTD_BLOCKSIZE AT24XX_PAGESIZE +#endif + +/************************************************************************************ + * 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 at24c_dev_s. + */ + +struct at24c_dev_s +{ + struct mtd_dev_s mtd; /* MTD interface */ + FAR struct i2c_dev_s *dev; /* Saved I2C interface instance */ + uint8_t addr; /* I2C address */ + uint16_t pagesize; /* 32, 63 */ + uint16_t npages; /* 128, 256, 512, 1024 */ +}; + +/************************************************************************************ + * Private Function Prototypes + ************************************************************************************/ + +/* MTD driver methods */ + +static int at24c_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks); +static ssize_t at24c_bread(FAR struct mtd_dev_s *dev, off_t startblock, + size_t nblocks, FAR uint8_t *buf); +static ssize_t at24c_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, + size_t nblocks, FAR const uint8_t *buf); +static ssize_t at24c_read(FAR struct mtd_dev_s *dev, off_t offset, + size_t nbytes,FAR uint8_t *buffer); +static int at24c_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg); + +/************************************************************************************ + * Private Data + ************************************************************************************/ + +/* At present, only a signal AT24 part is supported. In this case, a statically + * allocated state structure may be used. + */ + +static struct at24c_dev_s g_at24c; + +/************************************************************************************ + * Private Functions + ************************************************************************************/ + +static int at24c_eraseall(FAR struct at24c_dev_s *priv) +{ + int startblock = 0; + uint8_t buf[AT24XX_PAGESIZE + 2]; + + memset(&buf[2],0xff,priv->pagesize); + I2C_SETADDRESS(priv->dev,priv->addr,7); + I2C_SETFREQUENCY(priv->dev,100000); + + for (startblock = 0; startblock < priv->npages; startblock++) + { + uint16_t offset = startblock * priv->pagesize; + buf[1] = offset & 0xff; + buf[0] = (offset >> 8) & 0xff; + + while (I2C_WRITE(priv->dev, buf, 2) < 0) + { + usleep(1000); + } + I2C_WRITE(priv->dev, buf, priv->pagesize + 2); + } + + return OK; +} + +/************************************************************************************ + * Name: at24c_erase + ************************************************************************************/ + +static int at24c_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks) +{ + /* EEprom need not erase */ + + return (int)nblocks; +} + +/************************************************************************************ + * Name: at24c_bread + ************************************************************************************/ + +static ssize_t at24c_bread(FAR struct mtd_dev_s *dev, off_t startblock, + size_t nblocks, FAR uint8_t *buffer) +{ + FAR struct at24c_dev_s *priv = (FAR struct at24c_dev_s *)dev; + size_t blocksleft; + +#if CONFIG_AT24XX_MTD_BLOCKSIZE > AT24XX_PAGESIZE + startblock *= CONFIG_AT24XX_MTD_BLOCKSIZE / AT24XX_PAGESIZE; + nblocks *= CONFIG_AT24XX_MTD_BLOCKSIZE / AT24XX_PAGESIZE; +#endif + blocksleft = nblocks; + + fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks); + + if (startblock >= priv->npages) + { + return 0; + } + + if (startblock + nblocks > priv->npages) + { + nblocks = priv->npages - startblock; + } + + I2C_SETADDRESS(priv->dev,priv->addr,7); + I2C_SETFREQUENCY(priv->dev,100000); + + while (blocksleft-- > 0) + { + uint16_t offset = startblock * priv->pagesize; + uint8_t buf[2]; + buf[1] = offset & 0xff; + buf[0] = (offset >> 8) & 0xff; + + while (I2C_WRITE(priv->dev, buf, 2) < 0) + { + fvdbg("wait\n"); + usleep(1000); + } + + I2C_READ(priv->dev, buffer, priv->pagesize); + startblock++; + buffer += priv->pagesize; + } + +#if CONFIG_AT24XX_MTD_BLOCKSIZE > AT24XX_PAGESIZE + return nblocks / (CONFIG_AT24XX_MTD_BLOCKSIZE / AT24XX_PAGESIZE); +#else + return nblocks; +#endif +} + +/************************************************************************************ + * Name: at24c_bwrite + * + * Operates on MTD block's and translates to FLASH pages + * + ************************************************************************************/ + +static ssize_t at24c_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, + FAR const uint8_t *buffer) +{ + FAR struct at24c_dev_s *priv = (FAR struct at24c_dev_s *)dev; + size_t blocksleft; + uint8_t buf[AT24XX_PAGESIZE+2]; + +#if CONFIG_AT24XX_MTD_BLOCKSIZE > AT24XX_PAGESIZE + startblock *= CONFIG_AT24XX_MTD_BLOCKSIZE / AT24XX_PAGESIZE; + nblocks *= CONFIG_AT24XX_MTD_BLOCKSIZE / AT24XX_PAGESIZE; +#endif + blocksleft = nblocks; + + if (startblock >= priv->npages) + { + return 0; + } + + if (startblock + nblocks > priv->npages) + { + nblocks = priv->npages - startblock; + } + + fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks); + I2C_SETADDRESS(priv->dev, priv->addr, 7); + I2C_SETFREQUENCY(priv->dev, 100000); + + while (blocksleft-- > 0) + { + uint16_t offset = startblock * priv->pagesize; + while (I2C_WRITE(priv->dev, (uint8_t *)&offset, 2) < 0) + { + fvdbg("wait\n"); + usleep(1000); + } + + buf[1] = offset & 0xff; + buf[0] = (offset >> 8) & 0xff; + memcpy(&buf[2], buffer, priv->pagesize); + + I2C_WRITE(priv->dev, buf, priv->pagesize + 2); + startblock++; + buffer += priv->pagesize; + } + +#if CONFIG_AT24XX_MTD_BLOCKSIZE > AT24XX_PAGESIZE + return nblocks /(CONFIG_AT24XX_MTD_BLOCKSIZE / AT24XX_PAGESIZE); +#else + return nblocks; +#endif +} + +/************************************************************************************ + * Name: at24c_ioctl + ************************************************************************************/ + +static int at24c_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg) +{ + FAR struct at24c_dev_s *priv = (FAR struct at24c_dev_s *)dev; + int ret = -EINVAL; /* Assume good command with bad parameters */ + + fvdbg("cmd: %d \n", cmd); + + switch (cmd) + { + case MTDIOC_GEOMETRY: + { + FAR struct mtd_geometry_s *geo = (FAR struct mtd_geometry_s *)((uintptr_t)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. + * + * blocksize: + * May be user defined. The block size for the at24XX devices may be + * larger than the page size in order to better support file systems. + * The read and write functions translate BLOCKS to pages for the + * small flash devices + * erasesize: + * It has to be at least as big as the blocksize, bigger serves no + * purpose. + * neraseblocks + * Note that the device size is in kb, so * 1024 / 8 for bytes + */ + +#if CONFIG_AT24XX_MTD_BLOCKSIZE > AT24XX_PAGESIZE + geo->blocksize = CONFIG_AT24XX_MTD_BLOCKSIZE; + geo->erasesize = geo->blocksize; + geo->neraseblocks = CONFIG_AT24XX_SIZE * (1024/8) / geo->erasesize; +#else + geo->blocksize = priv->pagesize; + geo->erasesize = priv->pagesize; + geo->neraseblocks = priv->npages; +#endif + ret = OK; + + fvdbg("blocksize: %d erasesize: %d neraseblocks: %d\n", + geo->blocksize, geo->erasesize, geo->neraseblocks); + } + } + break; + + case MTDIOC_BULKERASE: + ret=at24c_eraseall(priv); + break; + + case MTDIOC_XIPBASE: + default: + ret = -ENOTTY; /* Bad command */ + break; + } + + return ret; +} + +/************************************************************************************ + * Public Functions + ************************************************************************************/ + +/************************************************************************************ + * Name: at24c_initialize + * + * Description: + * Create an initialize 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). + * + ************************************************************************************/ + +FAR struct mtd_dev_s *at24c_initialize(FAR struct i2c_dev_s *dev) +{ + FAR struct at24c_dev_s *priv; + + fvdbg("dev: %p\n", dev); + + /* Allocate a state structure (we allocate the structure instead of using + * a fixed, static allocation so that we can handle multiple FLASH devices. + * The current implementation would handle only one FLASH part per I2C + * device (only because of the SPIDEV_FLASH definition) and so would have + * to be extended to handle multiple FLASH parts on the same I2C bus. + */ + + priv = &g_at24c; + if (priv) + { + /* Initialize the allocated structure */ + + priv->addr = CONFIG_AT24XX_ADDR; + priv->pagesize = AT24XX_PAGESIZE; + priv->npages = AT24XX_NPAGES; + + priv->mtd.erase = at24c_erase; + priv->mtd.bread = at24c_bread; + priv->mtd.bwrite = at24c_bwrite; + priv->mtd.ioctl = at24c_ioctl; + priv->dev = dev; + } + + /* Return the implementation-specific state structure as the MTD device */ + + fvdbg("Return %p\n", priv); + return (FAR struct mtd_dev_s *)priv; +} + +#endif |