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author | Lorenz Meier <lm@inf.ethz.ch> | 2013-06-01 01:04:32 +0200 |
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committer | Lorenz Meier <lm@inf.ethz.ch> | 2013-06-01 01:04:32 +0200 |
commit | 5375bb5b86e266157ceceef08c367da711b8144e (patch) | |
tree | 88bc81cab11d8f0b2b6f9391f803051c081b2ecb /nuttx/drivers/mtd/m25px.c | |
parent | 27ee36b2049167a1272122548fe61aa2993d79c1 (diff) | |
download | px4-firmware-5375bb5b86e266157ceceef08c367da711b8144e.tar.gz px4-firmware-5375bb5b86e266157ceceef08c367da711b8144e.tar.bz2 px4-firmware-5375bb5b86e266157ceceef08c367da711b8144e.zip |
Cleanup, WIP, needs a NuttX checkout to Firmware/NuttX now
Diffstat (limited to 'nuttx/drivers/mtd/m25px.c')
-rw-r--r-- | nuttx/drivers/mtd/m25px.c | 798 |
1 files changed, 0 insertions, 798 deletions
diff --git a/nuttx/drivers/mtd/m25px.c b/nuttx/drivers/mtd/m25px.c deleted file mode 100644 index 4f96c5a3b..000000000 --- a/nuttx/drivers/mtd/m25px.c +++ /dev/null @@ -1,798 +0,0 @@ -/************************************************************************************ - * drivers/mtd/m25px.c - * Driver for SPI-based M25P1 (128Kbit), M25P64 (32Mbit), M25P64 (64Mbit), and - * M25P128 (128Mbit) FLASH (and compatible). - * - * 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 <errno.h> -#include <debug.h> - -#include <nuttx/kmalloc.h> -#include <nuttx/fs/ioctl.h> -#include <nuttx/spi.h> -#include <nuttx/mtd.h> - -/************************************************************************************ - * Pre-processor Definitions - ************************************************************************************/ -/* Configuration ********************************************************************/ -/* Per the data sheet, MP25P10 parts can be driven with either SPI mode 0 (CPOL=0 and - * CPHA=0) or mode 3 (CPOL=1 and CPHA=1). But I have heard that other devices can - * operated in mode 0 or 1. So you may need to specify CONFIG_MP25P_SPIMODE to - * select the best mode for your device. If CONFIG_MP25P_SPIMODE is not defined, - * mode 0 will be used. - */ - -#ifndef CONFIG_MP25P_SPIMODE -# define CONFIG_MP25P_SPIMODE SPIDEV_MODE0 -#endif - -/* Various manufacturers may have produced the parts. 0x20 is the manufacturer ID - * for the STMicro MP25x serial FLASH. If, for example, you are using the a Macronix - * International MX25 serial FLASH, the correct manufacturer ID would be 0xc2. - */ - -#ifndef CONFIG_MP25P_MANUFACTURER -# define CONFIG_MP25P_MANUFACTURER 0x20 -#endif - -/* M25P Registers *******************************************************************/ -/* Indentification register values */ - -#define M25P_MANUFACTURER CONFIG_MP25P_MANUFACTURER -#define M25P_MEMORY_TYPE 0x20 -#define M25P_M25P1_CAPACITY 0x11 /* 1 M-bit */ -#define M25P_M25P32_CAPACITY 0x16 /* 32 M-bit */ -#define M25P_M25P64_CAPACITY 0x17 /* 64 M-bit */ -#define M25P_M25P128_CAPACITY 0x18 /* 128 M-bit */ - -/* M25P1 capacity is 131,072 bytes: - * (4 sectors) * (32,768 bytes per sector) - * (512 pages) * (256 bytes per page) - */ - -#define M25P_M25P1_SECTOR_SHIFT 15 /* Sector size 1 << 15 = 65,536 */ -#define M25P_M25P1_NSECTORS 4 -#define M25P_M25P1_PAGE_SHIFT 8 /* Page size 1 << 8 = 256 */ -#define M25P_M25P1_NPAGES 512 - -/* M25P32 capacity is 4,194,304 bytes: - * (64 sectors) * (65,536 bytes per sector) - * (16384 pages) * (256 bytes per page) - */ - -#define M25P_M25P32_SECTOR_SHIFT 16 /* Sector size 1 << 16 = 65,536 */ -#define M25P_M25P32_NSECTORS 64 -#define M25P_M25P32_PAGE_SHIFT 8 /* Page size 1 << 8 = 256 */ -#define M25P_M25P32_NPAGES 16384 - -/* M25P64 capacity is 8,338,608 bytes: - * (128 sectors) * (65,536 bytes per sector) - * (32768 pages) * (256 bytes per page) - */ - -#define M25P_M25P64_SECTOR_SHIFT 16 /* Sector size 1 << 16 = 65,536 */ -#define M25P_M25P64_NSECTORS 128 -#define M25P_M25P64_PAGE_SHIFT 8 /* Page size 1 << 8 = 256 */ -#define M25P_M25P64_NPAGES 32768 - -/* M25P128 capacity is 16,777,216 bytes: - * (64 sectors) * (262,144 bytes per sector) - * (65536 pages) * (256 bytes per page) - */ - -#define M25P_M25P128_SECTOR_SHIFT 18 /* Sector size 1 << 18 = 262,144 */ -#define M25P_M25P128_NSECTORS 64 -#define M25P_M25P128_PAGE_SHIFT 8 /* Page size 1 << 8 = 256 */ -#define M25P_M25P128_NPAGES 65536 - -/* Instructions */ -/* Command Value N Description Addr Dummy Data */ -#define M25P_WREN 0x06 /* 1 Write Enable 0 0 0 */ -#define M25P_WRDI 0x04 /* 1 Write Disable 0 0 0 */ -#define M25P_RDID 0x9f /* 1 Read Identification 0 0 1-3 */ -#define M25P_RDSR 0x05 /* 1 Read Status Register 0 0 >=1 */ -#define M25P_WRSR 0x01 /* 1 Write Status Register 0 0 1 */ -#define M25P_READ 0x03 /* 1 Read Data Bytes 3 0 >=1 */ -#define M25P_FAST_READ 0x0b /* 1 Higher speed read 3 1 >=1 */ -#define M25P_PP 0x02 /* 1 Page Program 3 0 1-256 */ -#define M25P_SE 0xd8 /* 1 Sector Erase 3 0 0 */ -#define M25P_BE 0xc7 /* 1 Bulk Erase 0 0 0 */ -#define M25P_DP 0xb9 /* 2 Deep power down 0 0 0 */ -#define M25P_RES 0xab /* 2 Read Electronic Signature 0 3 >=1 */ - -/* NOTE 1: All parts, NOTE 2: M25P632/M25P64 */ - -/* Status register bit definitions */ - -#define M25P_SR_WIP (1 << 0) /* Bit 0: Write in progress bit */ -#define M25P_SR_WEL (1 << 1) /* Bit 1: Write enable latch bit */ -#define M25P_SR_BP_SHIFT (2) /* Bits 2-4: Block protect bits */ -#define M25P_SR_BP_MASK (7 << M25P_SR_BP_SHIFT) -# define M25P_SR_BP_NONE (0 << M25P_SR_BP_SHIFT) /* Unprotected */ -# define M25P_SR_BP_UPPER64th (1 << M25P_SR_BP_SHIFT) /* Upper 64th */ -# define M25P_SR_BP_UPPER32nd (2 << M25P_SR_BP_SHIFT) /* Upper 32nd */ -# define M25P_SR_BP_UPPER16th (3 << M25P_SR_BP_SHIFT) /* Upper 16th */ -# define M25P_SR_BP_UPPER8th (4 << M25P_SR_BP_SHIFT) /* Upper 8th */ -# define M25P_SR_BP_UPPERQTR (5 << M25P_SR_BP_SHIFT) /* Upper quarter */ -# define M25P_SR_BP_UPPERHALF (6 << M25P_SR_BP_SHIFT) /* Upper half */ -# define M25P_SR_BP_ALL (7 << M25P_SR_BP_SHIFT) /* All sectors */ - /* Bits 5-6: Unused, read zero */ -#define M25P_SR_SRWD (1 << 7) /* Bit 7: Status register write protect */ - -#define M25P_DUMMY 0xa5 - -/************************************************************************************ - * 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 m25p_dev_s. - */ - -struct m25p_dev_s -{ - struct mtd_dev_s mtd; /* MTD interface */ - FAR struct spi_dev_s *dev; /* Saved SPI interface instance */ - uint8_t sectorshift; /* 16 or 18 */ - uint8_t pageshift; /* 8 */ - uint16_t nsectors; /* 128 or 64 */ - uint32_t npages; /* 32,768 or 65,536 */ -}; - -/************************************************************************************ - * Private Function Prototypes - ************************************************************************************/ - -/* Helpers */ - -static void m25p_lock(FAR struct spi_dev_s *dev); -static inline void m25p_unlock(FAR struct spi_dev_s *dev); -static inline int m25p_readid(struct m25p_dev_s *priv); -static void m25p_waitwritecomplete(struct m25p_dev_s *priv); -static void m25p_writeenable(struct m25p_dev_s *priv); -static inline void m25p_sectorerase(struct m25p_dev_s *priv, off_t offset); -static inline int m25p_bulkerase(struct m25p_dev_s *priv); -static inline void m25p_pagewrite(struct m25p_dev_s *priv, FAR const uint8_t *buffer, - off_t offset); - -/* MTD driver methods */ - -static int m25p_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks); -static ssize_t m25p_bread(FAR struct mtd_dev_s *dev, off_t startblock, - size_t nblocks, FAR uint8_t *buf); -static ssize_t m25p_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, - size_t nblocks, FAR const uint8_t *buf); -static ssize_t m25p_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes, - FAR uint8_t *buffer); -static int m25p_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg); - -/************************************************************************************ - * Private Data - ************************************************************************************/ - -/************************************************************************************ - * Private Functions - ************************************************************************************/ - -/************************************************************************************ - * Name: m25p_lock - ************************************************************************************/ - -static void m25p_lock(FAR struct spi_dev_s *dev) -{ - /* On SPI busses where there are multiple devices, it will be necessary to - * lock SPI to have exclusive access to the busses 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 exclusiv 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 buss is being shared, then it may have been left in an incompatible - * state. - */ - - SPI_SETMODE(dev, CONFIG_MP25P_SPIMODE); - SPI_SETBITS(dev, 8); - (void)SPI_SETFREQUENCY(dev, 20000000); -} - -/************************************************************************************ - * Name: m25p_unlock - ************************************************************************************/ - -static inline void m25p_unlock(FAR struct spi_dev_s *dev) -{ - (void)SPI_LOCK(dev, false); -} - -/************************************************************************************ - * Name: m25p_readid - ************************************************************************************/ - -static inline int m25p_readid(struct m25p_dev_s *priv) -{ - uint16_t manufacturer; - uint16_t memory; - uint16_t capacity; - - fvdbg("priv: %p\n", priv); - - /* Lock the SPI bus, configure the bus, and select this FLASH part. */ - - m25p_lock(priv->dev); - SPI_SELECT(priv->dev, SPIDEV_FLASH, true); - - /* Send the "Read ID (RDID)" command and read the first three ID bytes */ - - (void)SPI_SEND(priv->dev, M25P_RDID); - manufacturer = SPI_SEND(priv->dev, M25P_DUMMY); - memory = SPI_SEND(priv->dev, M25P_DUMMY); - capacity = SPI_SEND(priv->dev, M25P_DUMMY); - - /* Deselect the FLASH and unlock the bus */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, false); - m25p_unlock(priv->dev); - - fvdbg("manufacturer: %02x memory: %02x capacity: %02x\n", - manufacturer, memory, capacity); - - /* Check for a valid manufacturer and memory type */ - - if (manufacturer == M25P_MANUFACTURER && memory == M25P_MEMORY_TYPE) - { - /* Okay.. is it a FLASH capacity that we understand? */ - - if (capacity == M25P_M25P1_CAPACITY) - { - /* Save the FLASH geometry */ - - priv->sectorshift = M25P_M25P1_SECTOR_SHIFT; - priv->nsectors = M25P_M25P1_NSECTORS; - priv->pageshift = M25P_M25P1_PAGE_SHIFT; - priv->npages = M25P_M25P1_NPAGES; - return OK; - } - else if (capacity == M25P_M25P32_CAPACITY) - { - /* Save the FLASH geometry */ - - priv->sectorshift = M25P_M25P32_SECTOR_SHIFT; - priv->nsectors = M25P_M25P32_NSECTORS; - priv->pageshift = M25P_M25P32_PAGE_SHIFT; - priv->npages = M25P_M25P32_NPAGES; - return OK; - } - else if (capacity == M25P_M25P64_CAPACITY) - { - /* Save the FLASH geometry */ - - priv->sectorshift = M25P_M25P64_SECTOR_SHIFT; - priv->nsectors = M25P_M25P64_NSECTORS; - priv->pageshift = M25P_M25P64_PAGE_SHIFT; - priv->npages = M25P_M25P64_NPAGES; - return OK; - } - else if (capacity == M25P_M25P128_CAPACITY) - { - /* Save the FLASH geometry */ - - priv->sectorshift = M25P_M25P128_SECTOR_SHIFT; - priv->nsectors = M25P_M25P128_NSECTORS; - priv->pageshift = M25P_M25P128_PAGE_SHIFT; - priv->npages = M25P_M25P128_NPAGES; - return OK; - } - } - - return -ENODEV; -} - -/************************************************************************************ - * Name: m25p_waitwritecomplete - ************************************************************************************/ - -static void m25p_waitwritecomplete(struct m25p_dev_s *priv) -{ - uint8_t status; - - /* Are we the only device on the bus? */ - -#ifdef CONFIG_SPI_OWNBUS - - /* Select this FLASH part */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, true); - - /* Send "Read Status Register (RDSR)" command */ - - (void)SPI_SEND(priv->dev, M25P_RDSR); - - /* Loop as long as the memory is busy with a write cycle */ - - do - { - /* Send a dummy byte to generate the clock needed to shift out the status */ - - status = SPI_SEND(priv->dev, M25P_DUMMY); - } - while ((status & M25P_SR_WIP) != 0); - - /* Deselect the FLASH */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, false); - -#else - - /* Loop as long as the memory is busy with a write cycle */ - - do - { - /* Select this FLASH part */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, true); - - /* Send "Read Status Register (RDSR)" command */ - - (void)SPI_SEND(priv->dev, M25P_RDSR); - - /* Send a dummy byte to generate the clock needed to shift out the status */ - - status = SPI_SEND(priv->dev, M25P_DUMMY); - - /* Deselect the FLASH */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, false); - - /* Given that writing could take up to few tens of milliseconds, and erasing - * could take more. The following short delay in the "busy" case will allow - * other peripherals to access the SPI bus. - */ - - if ((status & M25P_SR_WIP) != 0) - { - m25p_unlock(priv->dev); - usleep(1000); - m25p_lock(priv->dev); - } - } - while ((status & M25P_SR_WIP) != 0); -#endif - - fvdbg("Complete\n"); -} - -/************************************************************************************ - * Name: m25p_writeenable - ************************************************************************************/ - -static void m25p_writeenable(struct m25p_dev_s *priv) -{ - /* Select this FLASH part */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, true); - - /* Send "Write Enable (WREN)" command */ - - (void)SPI_SEND(priv->dev, M25P_WREN); - - /* Deselect the FLASH */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, false); - fvdbg("Enabled\n"); -} - -/************************************************************************************ - * Name: m25p_sectorerase - ************************************************************************************/ - -static inline void m25p_sectorerase(struct m25p_dev_s *priv, off_t sector) -{ - off_t offset = sector << priv->sectorshift; - - fvdbg("sector: %08lx\n", (long)sector); - - /* 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. - */ - - m25p_waitwritecomplete(priv); - - /* Send write enable instruction */ - - m25p_writeenable(priv); - - /* Select this FLASH part */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, true); - - /* Send the "Sector Erase (SE)" instruction */ - - (void)SPI_SEND(priv->dev, M25P_SE); - - /* Send the sector offset high byte first. For all of the supported - * parts, the sector number is completely contained in the first byte - * and the values used in the following two bytes don't really matter. - */ - - (void)SPI_SEND(priv->dev, (offset >> 16) & 0xff); - (void)SPI_SEND(priv->dev, (offset >> 8) & 0xff); - (void)SPI_SEND(priv->dev, offset & 0xff); - - /* Deselect the FLASH */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, false); - fvdbg("Erased\n"); -} - -/************************************************************************************ - * Name: m25p_bulkerase - ************************************************************************************/ - -static inline int m25p_bulkerase(struct m25p_dev_s *priv) -{ - fvdbg("priv: %p\n", priv); - - /* 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. - */ - - m25p_waitwritecomplete(priv); - - /* Send write enable instruction */ - - m25p_writeenable(priv); - - /* Select this FLASH part */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, true); - - /* Send the "Bulk Erase (BE)" instruction */ - - (void)SPI_SEND(priv->dev, M25P_BE); - - /* Deselect the FLASH */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, false); - fvdbg("Return: OK\n"); - return OK; -} - -/************************************************************************************ - * Name: m25p_pagewrite - ************************************************************************************/ - -static inline void m25p_pagewrite(struct m25p_dev_s *priv, FAR const uint8_t *buffer, - off_t page) -{ - off_t offset = page << priv->pageshift; - - fvdbg("page: %08lx offset: %08lx\n", (long)page, (long)offset); - - /* 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. - */ - - m25p_waitwritecomplete(priv); - - /* Enable the write access to the FLASH */ - - m25p_writeenable(priv); - - /* Select this FLASH part */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, true); - - /* Send "Page Program (PP)" command */ - - (void)SPI_SEND(priv->dev, M25P_PP); - - /* Send the page offset high byte first. */ - - (void)SPI_SEND(priv->dev, (offset >> 16) & 0xff); - (void)SPI_SEND(priv->dev, (offset >> 8) & 0xff); - (void)SPI_SEND(priv->dev, offset & 0xff); - - /* 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); - fvdbg("Written\n"); -} - -/************************************************************************************ - * Name: m25p_erase - ************************************************************************************/ - -static int m25p_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks) -{ - FAR struct m25p_dev_s *priv = (FAR struct m25p_dev_s *)dev; - size_t blocksleft = nblocks; - - fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks); - - /* Lock access to the SPI bus until we complete the erase */ - - m25p_lock(priv->dev); - while (blocksleft-- > 0) - { - /* Erase each sector */ - - m25p_sectorerase(priv, startblock); - startblock++; - } - m25p_unlock(priv->dev); - return (int)nblocks; -} - -/************************************************************************************ - * Name: m25p_bread - ************************************************************************************/ - -static ssize_t m25p_bread(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, - FAR uint8_t *buffer) -{ - FAR struct m25p_dev_s *priv = (FAR struct m25p_dev_s *)dev; - ssize_t nbytes; - - fvdbg("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 = m25p_read(dev, startblock << priv->pageshift, nblocks << priv->pageshift, buffer); - if (nbytes > 0) - { - return nbytes >> priv->pageshift; - } - return (int)nbytes; -} - -/************************************************************************************ - * Name: m25p_bwrite - ************************************************************************************/ - -static ssize_t m25p_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, - FAR const uint8_t *buffer) -{ - FAR struct m25p_dev_s *priv = (FAR struct m25p_dev_s *)dev; - size_t blocksleft = nblocks; - - fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks); - - /* Lock the SPI bus and write each page to FLASH */ - - m25p_lock(priv->dev); - while (blocksleft-- > 0) - { - m25p_pagewrite(priv, buffer, startblock); - startblock++; - } - m25p_unlock(priv->dev); - - return nblocks; -} - -/************************************************************************************ - * Name: m25p_read - ************************************************************************************/ - -static ssize_t m25p_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes, - FAR uint8_t *buffer) -{ - FAR struct m25p_dev_s *priv = (FAR struct m25p_dev_s *)dev; - - fvdbg("offset: %08lx nbytes: %d\n", (long)offset, (int)nbytes); - - /* 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. - */ - - m25p_waitwritecomplete(priv); - - /* Lock the SPI bus and select this FLASH part */ - - m25p_lock(priv->dev); - SPI_SELECT(priv->dev, SPIDEV_FLASH, true); - - /* Send "Read from Memory " instruction */ - - (void)SPI_SEND(priv->dev, M25P_READ); - - /* Send the page offset high byte first. */ - - (void)SPI_SEND(priv->dev, (offset >> 16) & 0xff); - (void)SPI_SEND(priv->dev, (offset >> 8) & 0xff); - (void)SPI_SEND(priv->dev, offset & 0xff); - - /* Then read all of the requested bytes */ - - SPI_RECVBLOCK(priv->dev, buffer, nbytes); - - /* Deselect the FLASH and unlock the SPI bus */ - - SPI_SELECT(priv->dev, SPIDEV_FLASH, false); - m25p_unlock(priv->dev); - fvdbg("return nbytes: %d\n", (int)nbytes); - return nbytes; -} - -/************************************************************************************ - * Name: m25p_ioctl - ************************************************************************************/ - -static int m25p_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg) -{ - FAR struct m25p_dev_s *priv = (FAR struct m25p_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 = (1 << priv->pageshift); - geo->erasesize = (1 << priv->sectorshift); - geo->neraseblocks = priv->nsectors; - ret = OK; - - fvdbg("blocksize: %d erasesize: %d neraseblocks: %d\n", - geo->blocksize, geo->erasesize, geo->neraseblocks); - } - } - break; - - case MTDIOC_BULKERASE: - { - /* Erase the entire device */ - - m25p_lock(priv->dev); - ret = m25p_bulkerase(priv); - m25p_unlock(priv->dev); - } - break; - - case MTDIOC_XIPBASE: - default: - ret = -ENOTTY; /* Bad command */ - break; - } - - fvdbg("return %d\n", ret); - return ret; -} - -/************************************************************************************ - * Public Functions - ************************************************************************************/ - -/************************************************************************************ - * Name: m25p_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 *m25p_initialize(FAR struct spi_dev_s *dev) -{ - FAR struct m25p_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 = (FAR struct m25p_dev_s *)kmalloc(sizeof(struct m25p_dev_s)); - if (priv) - { - /* Initialize the allocated structure */ - - priv->mtd.erase = m25p_erase; - priv->mtd.bread = m25p_bread; - priv->mtd.bwrite = m25p_bwrite; - priv->mtd.read = m25p_read; - priv->mtd.ioctl = m25p_ioctl; - priv->dev = dev; - - /* Deselect the FLASH */ - - SPI_SELECT(dev, SPIDEV_FLASH, false); - - /* Identify the FLASH chip and get its capacity */ - - ret = m25p_readid(priv); - if (ret != OK) - { - /* Unrecognized! Discard all of that work we just did and return NULL */ - - fdbg("Unrecognized\n"); - kfree(priv); - priv = NULL; - } - } - - /* Return the implementation-specific state structure as the MTD device */ - - fvdbg("Return %p\n", priv); - return (FAR struct mtd_dev_s *)priv; -} |