incubator-nuttx/drivers/mtd/ramtron.c

852 lines
28 KiB
C

/************************************************************************************
* drivers/mtd/ramtron.c
* Driver for SPI-based RAMTRON NVRAM Devices FM25V10 and others (not tested)
*
* Copyright (C) 2011 Uros Platise. All rights reserved.
* Copyright (C) 2009-2010, 2012-2013 Gregory Nutt. All rights reserved.
* Author: Uros Platise <uros.platise@isotel.eu>
* 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.
*
************************************************************************************/
/* OPTIONS:
* - additional non-jedec standard device: FM25H20
* must be enabled with the CONFIG_RAMTRON_FRAM_NON_JEDEC=y
*
* NOTE:
* - frequency is fixed to desired max by RAMTRON_INIT_CLK_MAX if new devices with
* different speed arrive, use the table to handle freq change and to fit all
* devices. Note that STM32_SPI driver is prone to too high freq. parameters and
* limit it within physical constraints. The speed may be changed through ioctl
* MTDIOC_SETSPEED
*
* TODO:
* - add support for sleep
* - add support for faster read FSTRD command
*/
/************************************************************************************
* 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 <assert.h>
#include <nuttx/kmalloc.h>
#include <nuttx/fs/ioctl.h>
#include <nuttx/spi/spi.h>
#include <nuttx/mtd/mtd.h>
/************************************************************************************
* Pre-processor Definitions
************************************************************************************/
/* Used to abort the write wait */
#ifndef CONFIG_MTD_RAMTRON_WRITEWAIT_COUNT
# define CONFIG_MTD_RAMTRON_WRITEWAIT_COUNT 100
#endif
/* RAMTRON devices are flat!
* For purpose of the VFAT file system we emulate the following configuration:
*/
#define RAMTRON_EMULATE_SECTOR_SHIFT 9
#define RAMTRON_EMULATE_PAGE_SHIFT 9
/* RAMTRON Identification register values */
#define RAMTRON_MANUFACTURER 0x7F
#define RAMTRON_MEMORY_TYPE 0xC2
/* Instructions:
* Command Value N Description Addr Dummy Data */
#define RAMTRON_WREN 0x06 /* 1 Write Enable 0 0 0 */
#define RAMTRON_WRDI 0x04 /* 1 Write Disable 0 0 0 */
#define RAMTRON_RDSR 0x05 /* 1 Read Status Register 0 0 >=1 */
#define RAMTRON_WRSR 0x01 /* 1 Write Status Register 0 0 1 */
#define RAMTRON_READ 0x03 /* 1 Read Data Bytes A 0 >=1 */
#define RAMTRON_FSTRD 0x0b /* 1 Higher speed read A 1 >=1 */
#define RAMTRON_WRITE 0x02 /* 1 Write A 0 1-256 */
#define RAMTRON_SLEEP 0xb9 /* TODO: */
#define RAMTRON_RDID 0x9f /* 1 Read Identification 0 0 1-3 */
#define RAMTRON_SN 0xc3 /* TODO: */
/* Status register bit definitions */
#define RAMTRON_SR_WIP (1 << 0) /* Bit 0: Write in progress bit */
#define RAMTRON_SR_WEL (1 << 1) /* Bit 1: Write enable latch bit */
#define RAMTRON_SR_BP_SHIFT (2) /* Bits 2-4: Block protect bits */
#define RAMTRON_SR_BP_MASK (7 << RAMTRON_SR_BP_SHIFT)
# define RAMTRON_SR_BP_NONE (0 << RAMTRON_SR_BP_SHIFT) /* Unprotected */
# define RAMTRON_SR_BP_UPPER64th (1 << RAMTRON_SR_BP_SHIFT) /* Upper 64th */
# define RAMTRON_SR_BP_UPPER32nd (2 << RAMTRON_SR_BP_SHIFT) /* Upper 32nd */
# define RAMTRON_SR_BP_UPPER16th (3 << RAMTRON_SR_BP_SHIFT) /* Upper 16th */
# define RAMTRON_SR_BP_UPPER8th (4 << RAMTRON_SR_BP_SHIFT) /* Upper 8th */
# define RAMTRON_SR_BP_UPPERQTR (5 << RAMTRON_SR_BP_SHIFT) /* Upper quarter */
# define RAMTRON_SR_BP_UPPERHALF (6 << RAMTRON_SR_BP_SHIFT) /* Upper half */
# define RAMTRON_SR_BP_ALL (7 << RAMTRON_SR_BP_SHIFT) /* All sectors */
#define RAMTRON_SR_SRWD (1 << 7) /* Bit 7: Status register write protect */
#define RAMTRON_DUMMY 0xa5
/************************************************************************************
* Private Types
************************************************************************************/
struct ramtron_parts_s
{
const char *name;
uint8_t id1;
uint8_t id2;
uint32_t size;
uint8_t addr_len;
uint32_t speed;
};
/* 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 ramtron_dev_s.
*/
struct ramtron_dev_s
{
struct mtd_dev_s mtd; /* MTD interface */
FAR struct spi_dev_s *dev; /* Saved SPI interface instance */
uint8_t sectorshift;
uint8_t pageshift;
uint16_t nsectors;
uint32_t npages;
uint32_t speed; /* Overridable via ioctl */
FAR const struct ramtron_parts_s *part; /* Part instance */
};
/************************************************************************************
* Supported Part Lists
************************************************************************************/
/* Defines the initial speed compatible with all devices. In case of RAMTRON
* the defined devices within the part list have all the same speed.
*/
#define RAMTRON_INIT_CLK_MAX 40000000UL
static const struct ramtron_parts_s g_ramtron_parts[] =
{
{
"FM25V01", /* name */
0x21, /* id1 */
0x00, /* id2 */
16L*1024L, /* size */
2, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"FM25V01A", /* name */
0x21, /* id1 */
0x08, /* id2 */
16L*1024L, /* size */
2, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"FM25V02", /* name */
0x22, /* id1 */
0x00, /* id2 */
32L*1024L, /* size */
2, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"FM25V02A", /* name */
0x22, /* id1 */
0x08, /* id2 */
32L*1024L, /* size */
2, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"FM25VN02", /* name */
0x22, /* id1 */
0x01, /* id2 */
32L*1024L, /* size */
2, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"FM25V05", /* name */
0x23, /* id1 */
0x00, /* id2 */
64L*1024L, /* size */
2, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"FM25VN05", /* name */
0x23, /* id1 */
0x01, /* id2 */
64L*1024L, /* size */
2, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"FM25V10", /* name */
0x24, /* id1 */
0x00, /* id2 */
128L*1024L, /* size */
3, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"FM25VN10", /* name */
0x24, /* id1 */
0x01, /* id2 */
128L*1024L, /* size */
3, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"FM25V20A", /* name */
0x25, /* id1 */
0x08, /* id2 */
256L*1024L, /* size */
3, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"CY15B104Q", /* name */
0x26, /* id1 */
0x08, /* id2 */
512L*1024L, /* size */
3, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
{
"MB85RS1MT", /* name */
0x27, /* id1 */
0x03, /* id2 */
128L*1024L, /* size */
3, /* addr_len */
25000000 /* speed */
},
{
"MB85RS256B", /* name */
0x05, /* id1 */
0x09, /* id2 */
32L*1024L, /* size */
3, /* addr_len */
25000000 /* speed */
},
#ifdef CONFIG_RAMTRON_FRAM_NON_JEDEC
{
"FM25H20", /* name */
0xff, /* id1 */
0xff, /* id2 */
256L*1024L, /* size */
3, /* addr_len */
RAMTRON_INIT_CLK_MAX /* speed */
},
#endif
{
NULL, /* name */
0, /* id1 */
0, /* id2 */
0, /* size */
0, /* addr_len */
0 /* speed */
}
};
/************************************************************************************
* Private Function Prototypes
************************************************************************************/
/* Helpers */
static void ramtron_lock(FAR struct ramtron_dev_s *priv);
static inline void ramtron_unlock(FAR struct spi_dev_s *dev);
static inline int ramtron_readid(struct ramtron_dev_s *priv);
static int ramtron_waitwritecomplete(struct ramtron_dev_s *priv);
static void ramtron_writeenable(struct ramtron_dev_s *priv);
static inline int ramtron_pagewrite(struct ramtron_dev_s *priv,
FAR const uint8_t *buffer, off_t offset);
/* MTD driver methods */
static int ramtron_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks);
static ssize_t ramtron_bread(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR uint8_t *buf);
static ssize_t ramtron_bwrite(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR const uint8_t *buf);
static ssize_t ramtron_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes,
FAR uint8_t *buffer);
static int ramtron_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg);
/************************************************************************************
* Private Data
************************************************************************************/
/************************************************************************************
* Private Functions
************************************************************************************/
/************************************************************************************
* Name: ramtron_lock
************************************************************************************/
static void ramtron_lock(FAR struct ramtron_dev_s *priv)
{
FAR struct spi_dev_s *dev = priv->dev;
/* On SPI buses where there are multiple devices, it will be necessary to
* lock SPI to have exclusive access to the buses for a sequence of
* transfers. The bus should be locked before the chip is selected.
*
* This is a blocking call and will not return until we have exclusive access to
* the SPI buss. We will retain that exclusive access until the bus is unlocked.
*/
(void)SPI_LOCK(dev, true);
/* After locking the SPI bus, the we also need call the setfrequency, setbits, and
* setmode methods to make sure that the SPI is properly configured for the device.
* If the SPI bus is being shared, then it may have been left in an incompatible
* state.
*/
SPI_SETMODE(dev, SPIDEV_MODE3);
SPI_SETBITS(dev, 8);
(void)SPI_HWFEATURES(dev, 0);
(void)SPI_SETFREQUENCY(dev, priv->speed);
}
/************************************************************************************
* Name: ramtron_unlock
************************************************************************************/
static inline void ramtron_unlock(FAR struct spi_dev_s *dev)
{
(void)SPI_LOCK(dev, false);
}
/************************************************************************************
* Name: ramtron_readid
************************************************************************************/
static inline int ramtron_readid(struct ramtron_dev_s *priv)
{
uint16_t manufacturer;
uint16_t memory;
uint16_t capacity;
uint16_t part;
int i;
finfo("priv: %p\n", priv);
/* Lock the SPI bus, configure the bus, and select this FLASH part. */
ramtron_lock(priv);
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send the "Read ID (RDID)" command */
(void)SPI_SEND(priv->dev, RAMTRON_RDID);
/* Read the first six manufacturer ID bytes. */
for (i = 0; i < 6; i++)
{
/* Read the next manufacturer byte */
manufacturer = SPI_SEND(priv->dev, RAMTRON_DUMMY);
/* Fujitsu parts such as MB85RS1MT only have 1-byte for the manufacturer
* ID. The manufacturer code is "0x4".
*/
if (i == 0 && manufacturer == 0x04)
{
break;
}
}
memory = SPI_SEND(priv->dev, RAMTRON_DUMMY);
capacity = SPI_SEND(priv->dev, RAMTRON_DUMMY); /* fram.id1 */
part = SPI_SEND(priv->dev, RAMTRON_DUMMY); /* fram.id2 */
/* Deselect the FLASH and unlock the bus */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
ramtron_unlock(priv->dev);
/* Select part from the part list */
for (priv->part = g_ramtron_parts;
priv->part->name != NULL &&
!(priv->part->id1 == capacity && priv->part->id2 == part);
priv->part++);
if (priv->part->name)
{
UNUSED(manufacturer); /* Eliminate warnings when debug is off */
UNUSED(memory); /* Eliminate warnings when debug is off */
finfo("RAMTRON %s of size %d bytes (mf:%02x mem:%02x cap:%02x part:%02x)\n",
priv->part->name, priv->part->size, manufacturer, memory, capacity, part);
priv->sectorshift = RAMTRON_EMULATE_SECTOR_SHIFT;
priv->nsectors = priv->part->size / (1 << RAMTRON_EMULATE_SECTOR_SHIFT);
priv->pageshift = RAMTRON_EMULATE_PAGE_SHIFT;
priv->npages = priv->part->size / (1 << RAMTRON_EMULATE_PAGE_SHIFT);
priv->speed = priv->part->speed;
return OK;
}
finfo("RAMTRON device not found\n");
return -ENODEV;
}
/************************************************************************************
* Name: ramtron_waitwritecomplete
************************************************************************************/
static int ramtron_waitwritecomplete(struct ramtron_dev_s *priv)
{
uint8_t status;
int retries = CONFIG_MTD_RAMTRON_WRITEWAIT_COUNT;
/* Select this FLASH part */
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send "Read Status Register (RDSR)" command */
(void)SPI_SEND(priv->dev, RAMTRON_RDSR);
/* Loop as long as the memory is busy with a write cycle, but limit the
* cycles.
*
* RAMTRON FRAM is never busy per spec compared to flash, and so anything
* exceeding the default timeout number is highly suspicious.
*/
do
{
/* Send a dummy byte to generate the clock needed to shift out the status */
status = SPI_SEND(priv->dev, RAMTRON_DUMMY);
}
while ((status & RAMTRON_SR_WIP) != 0 && retries-- > 0);
/* Deselect the FLASH */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
if (retries > 0)
{
finfo("Complete\n");
retries = OK;
}
else
{
ferr("ERROR: timeout waiting for write completion\n");
retries = -EAGAIN;
}
return retries;
}
/************************************************************************************
* Name: ramtron_writeenable
************************************************************************************/
static void ramtron_writeenable(struct ramtron_dev_s *priv)
{
/* Select this FLASH part */
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send "Write Enable (WREN)" command */
(void)SPI_SEND(priv->dev, RAMTRON_WREN);
/* Deselect the FLASH */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
finfo("Enabled\n");
}
/************************************************************************************
* Name: ramtron_sendaddr
************************************************************************************/
static inline void ramtron_sendaddr(const struct ramtron_dev_s *priv, uint32_t addr)
{
DEBUGASSERT(priv->part->addr_len == 3 || priv->part->addr_len == 2);
if (priv->part->addr_len == 3)
{
(void)SPI_SEND(priv->dev, (addr >> 16) & 0xff);
}
(void)SPI_SEND(priv->dev, (addr >> 8) & 0xff);
(void)SPI_SEND(priv->dev, addr & 0xff);
}
/************************************************************************************
* Name: ramtron_pagewrite
************************************************************************************/
static inline int ramtron_pagewrite(struct ramtron_dev_s *priv, FAR const uint8_t *buffer,
off_t page)
{
off_t offset = page << priv->pageshift;
finfo("page: %08lx offset: %08lx\n", (long)page, (long)offset);
#ifndef RAMTRON_WRITEWAIT
/* Wait for any preceding write to complete. We could simplify things by
* perform this wait at the end of each write operation (rather than at
* the beginning of ALL operations), but have the wait first will slightly
* improve performance.
*/
(void)ramtron_waitwritecomplete(priv);
#endif
/* Enable the write access to the FLASH */
ramtron_writeenable(priv);
/* Select this FLASH part */
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send "Page Program (PP)" command */
(void)SPI_SEND(priv->dev, RAMTRON_WRITE);
/* Send the page offset high byte first. */
ramtron_sendaddr(priv, offset);
/* Then write the specified number of bytes */
SPI_SNDBLOCK(priv->dev, buffer, 1 << priv->pageshift);
/* Deselect the FLASH: Chip Select high */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
finfo("Written\n");
#ifdef RAMTRON_WRITEWAIT
/* Wait for write completion now so we can report any errors to the caller. Thus
* the caller will know whether or not if the data is on stable storage
*/
return ramtron_waitwritecomplete(priv);
#else
return OK;
#endif
}
/************************************************************************************
* Name: ramtron_erase
************************************************************************************/
static int ramtron_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks)
{
finfo("startblock: %08lx nblocks: %d\n", (unsigned long)startblock, (int)nblocks);
finfo("On RAMTRON devices erasing makes no sense, returning as OK\n");
return (int)nblocks;
}
/************************************************************************************
* Name: ramtron_bread
************************************************************************************/
static ssize_t ramtron_bread(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR uint8_t *buffer)
{
FAR struct ramtron_dev_s *priv = (FAR struct ramtron_dev_s *)dev;
ssize_t nbytes;
finfo("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
/* On this device, we can handle the block read just like the byte-oriented read */
nbytes = ramtron_read(dev, startblock << priv->pageshift,
nblocks << priv->pageshift, buffer);
if (nbytes > 0)
{
return nbytes >> priv->pageshift;
}
return (int)nbytes;
}
/************************************************************************************
* Name: ramtron_bwrite
************************************************************************************/
static ssize_t ramtron_bwrite(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR const uint8_t *buffer)
{
FAR struct ramtron_dev_s *priv = (FAR struct ramtron_dev_s *)dev;
size_t blocksleft = nblocks;
finfo("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
/* Lock the SPI bus and write each page to FLASH */
ramtron_lock(priv);
while (blocksleft-- > 0)
{
if (ramtron_pagewrite(priv, buffer, startblock))
{
nblocks = 0;
break;
}
startblock++;
}
ramtron_unlock(priv->dev);
return nblocks;
}
/************************************************************************************
* Name: ramtron_read
************************************************************************************/
static ssize_t ramtron_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes,
FAR uint8_t *buffer)
{
FAR struct ramtron_dev_s *priv = (FAR struct ramtron_dev_s *)dev;
#ifdef RAMTRON_WRITEWAIT
uint8_t status;
#endif
finfo("offset: %08lx nbytes: %d\n", (long)offset, (int)nbytes);
#ifndef RAMTRON_WRITEWAIT
/* Wait for any preceding write to complete. We could simplify things by
* perform this wait at the end of each write operation (rather than at
* the beginning of ALL operations), but have the wait first will slightly
* improve performance.
*/
(void)ramtron_waitwritecomplete(priv);
#endif
/* Lock the SPI bus and select this FLASH part */
ramtron_lock(priv);
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send "Read from Memory " instruction */
(void)SPI_SEND(priv->dev, RAMTRON_READ);
/* Send the page offset high byte first. */
ramtron_sendaddr(priv, offset);
/* Then read all of the requested bytes */
SPI_RECVBLOCK(priv->dev, buffer, nbytes);
#ifdef RAMTRON_WRITEWAIT
/* Read the status register. This isn't strictly needed, but it gives us a
* chance to detect if SPI transactions are operating correctly, which
* allows us to catch complete device failures in the read path. We expect
* the status register to just have the write enable bit set to the write
* enable state
*/
(void)SPI_SEND(priv->dev, RAMTRON_RDSR);
status = SPI_SEND(priv->dev, RAMTRON_DUMMY);
if ((status & ~RAMTRON_SR_SRWD) == 0)
{
ferr("ERROR: read status failed - got 0x%02x\n", (unsigned)status);
nbytes = -EIO;
}
#endif
/* Deselect the FLASH and unlock the SPI bus */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
ramtron_unlock(priv->dev);
finfo("return nbytes: %d\n", (int)nbytes);
return nbytes;
}
/************************************************************************************
* Name: ramtron_ioctl
************************************************************************************/
static int ramtron_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg)
{
FAR struct ramtron_dev_s *priv = (FAR struct ramtron_dev_s *)dev;
int ret = -EINVAL; /* Assume good command with bad parameters */
finfo("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 = (1 << priv->pageshift);
geo->erasesize = (1 << priv->sectorshift);
geo->neraseblocks = priv->nsectors;
ret = OK;
finfo("blocksize: %d erasesize: %d neraseblocks: %d\n",
geo->blocksize, geo->erasesize, geo->neraseblocks);
}
}
break;
case MTDIOC_BULKERASE:
finfo("BULDERASE: Makes no sense in ramtron. Let's confirm operation as OK\n");
ret = OK;
break;
#ifdef CONFIG_RAMTRON_SETSPEED
case MTDIOC_SETSPEED:
{
if (arg > 0 && arg <= RAMTRON_INIT_CLK_MAX)
{
priv->speed = arg;
finfo("set bus speed to %lu\n", priv->speed);
ret = OK;
}
}
break;
#endif
case MTDIOC_XIPBASE:
default:
ret = -ENOTTY; /* Bad command */
break;
}
finfo("return %d\n", ret);
return ret;
}
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: ramtron_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 *ramtron_initialize(FAR struct spi_dev_s *dev)
{
FAR struct ramtron_dev_s *priv;
finfo("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 = (FAR struct ramtron_dev_s *)kmm_zalloc(sizeof(struct ramtron_dev_s));
if (priv)
{
/* Initialize the allocated structure. (unsupported methods were
* nullified by kmm_zalloc).
*/
priv->mtd.erase = ramtron_erase;
priv->mtd.bread = ramtron_bread;
priv->mtd.bwrite = ramtron_bwrite;
priv->mtd.read = ramtron_read;
priv->mtd.ioctl = ramtron_ioctl;
priv->dev = dev;
/* Deselect the FLASH */
SPI_SELECT(dev, SPIDEV_FLASH, false);
/* Identify the FLASH chip and get its capacity */
if (ramtron_readid(priv) != OK)
{
/* Unrecognized! Discard all of that work we just did and return NULL */
kmm_free(priv);
return NULL;
}
}
/* Register the MTD with the procfs system if enabled */
#ifdef CONFIG_MTD_REGISTRATION
mtd_register(&priv->mtd, "ramtron");
#endif
/* Return the implementation-specific state structure as the MTD device */
finfo("Return %p\n", priv);
return (FAR struct mtd_dev_s *)priv;
}