/**************************************************************************** * drivers/mtd/at24xx.c * * Copyright (C) 2011 Li Zhuoyi. All rights reserved. * Copyright (C) 2013, 2016 Gregory Nutt. All rights reserved. * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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 #if !defined(CONFIG_AT24XX_ADDR) && !defined(CONFIG_AT24XX_MULTI) # warning "Assuming AT24 I2C address of 0x50" # define CONFIG_AT24XX_ADDR 0x50 #endif #ifndef CONFIG_AT24XX_FREQUENCY # warning "Assuming AT24 I2C frequency of 100KHz" # define CONFIG_AT24XX_FREQUENCY 100000 #endif /* Get the part configuration based on the size configuration */ #if CONFIG_AT24XX_SIZE == 2 /* AT24C02: 2Kbits = 256; 32 * 8 = 256 */ # define AT24XX_NPAGES 32 # define AT24XX_PAGESIZE 8 # define AT24XX_ADDRSIZE 1 #elif CONFIG_AT24XX_SIZE == 4 /* AT24C04: 4Kbits = 512B; 32 * 16 = 512 */ # define AT24XX_NPAGES 32 # define AT24XX_PAGESIZE 16 # define AT24XX_ADDRSIZE 1 #elif CONFIG_AT24XX_SIZE == 8 /* AT24C08: 8Kbits = 1KiB; 64 * 16 = 1024 */ # define AT24XX_NPAGES 64 # define AT24XX_PAGESIZE 16 # define AT24XX_ADDRSIZE 1 #elif CONFIG_AT24XX_SIZE == 16 /* AT24C16: 16Kbits = 2KiB; 128 * 16 = 2048 */ # define AT24XX_NPAGES 128 # define AT24XX_PAGESIZE 16 # define AT24XX_ADDRSIZE 1 #elif CONFIG_AT24XX_SIZE == 32 /* AT24C32: 32Kbits = 4KiB; 128 * 32 = 4096 */ # define AT24XX_NPAGES 128 # define AT24XX_PAGESIZE 32 # define AT24XX_ADDRSIZE 2 #elif CONFIG_AT24XX_SIZE == 48 /* AT24C48: 48Kbits = 6KiB; 192 * 32 = 6144 */ # define AT24XX_NPAGES 192 # define AT24XX_PAGESIZE 32 # define AT24XX_ADDRSIZE 2 #elif CONFIG_AT24XX_SIZE == 64 /* AT24C64: 64Kbits = 8KiB; 256 * 32 = 8192 */ # define AT24XX_NPAGES 256 # define AT24XX_PAGESIZE 32 # define AT24XX_ADDRSIZE 2 #elif CONFIG_AT24XX_SIZE == 128 /* AT24C128: 128Kbits = 16KiB; 256 * 64 = 16384 */ # define AT24XX_NPAGES 256 # define AT24XX_PAGESIZE 64 # define AT24XX_ADDRSIZE 2 #elif CONFIG_AT24XX_SIZE == 256 /* AT24C256: 256Kbits = 32KiB; 512 * 64 = 32768 */ # define AT24XX_NPAGES 512 # define AT24XX_PAGESIZE 64 # define AT24XX_ADDRSIZE 2 #elif CONFIG_AT24XX_SIZE == 512 /* AT24C512: 512Kbits = 64KiB; 512 * 128 = 65536 */ # define AT24XX_NPAGES 512 # define AT24XX_PAGESIZE 128 # define AT24XX_ADDRSIZE 2 #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 MTD driver block size is the same as the FLASH page size" # define CONFIG_AT24XX_MTD_BLOCKSIZE AT24XX_PAGESIZE #endif #ifndef CONFIG_AT24XX_TIMEOUT_MS # define CONFIG_AT24XX_TIMEOUT_MS 10 #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_master_s *dev; /* Saved I2C interface instance */ bool initd; /* True: The device has been initialize */ #ifdef CONFIG_AT24XX_EXTENDED bool extended; /* True: use extended memory region */ #endif 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 ****************************************************************************/ #ifndef CONFIG_AT24XX_MULTI /* If only a signal AT24 part is supported then a statically allocated state * structure may be used. */ static struct at24c_dev_s g_at24c; #endif /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: at24c_i2c_write * * Description: * Write to the I2C device. * ****************************************************************************/ static int at24c_i2c_write(FAR struct at24c_dev_s *priv, uint16_t at24addr, FAR const uint8_t *buffer, int buflen) { struct i2c_msg_s msg; /* Setup for the transfer */ msg.frequency = CONFIG_AT24XX_FREQUENCY, msg.addr = at24addr; msg.flags = 0; msg.buffer = (FAR uint8_t *)buffer; /* Override const */ msg.length = buflen; /* Then perform the transfer. */ return I2C_TRANSFER(priv->dev, &msg, 1); } /**************************************************************************** * Name: at24c_i2c_read * * Description: * Read from the I2C device. * ****************************************************************************/ static int at24c_i2c_read(FAR struct at24c_dev_s *priv, uint16_t at24addr, FAR uint8_t *buffer, int buflen) { struct i2c_msg_s msg; /* Setup for the transfer */ msg.frequency = CONFIG_AT24XX_FREQUENCY, msg.addr = at24addr, msg.flags = I2C_M_READ; msg.buffer = buffer; msg.length = buflen; /* Then perform the transfer. */ return I2C_TRANSFER(priv->dev, &msg, 1); } /**************************************************************************** * Name: at24c_eraseall ****************************************************************************/ static int at24c_eraseall(FAR struct at24c_dev_s *priv) { uint8_t buf[AT24XX_PAGESIZE + AT24XX_ADDRSIZE]; int startblock = 0; uint16_t wait; memset(&buf[AT24XX_ADDRSIZE], 0xff, priv->pagesize); for (startblock = 0; startblock < priv->npages; startblock++) { uint16_t offset = startblock * priv->pagesize; uint16_t at24addr; #if AT24XX_ADDRSIZE == 2 buf[1] = offset & 0xff; buf[0] = (offset >> 8) & 0xff; at24addr = priv->addr; #else buf[0] = offset & 0xff; at24addr = (priv->addr | ((offset >> 8) & 0x07)); #endif wait = CONFIG_AT24XX_TIMEOUT_MS; while (at24c_i2c_write(priv, at24addr, buf, AT24XX_ADDRSIZE) < 0) { finfo("wait\n"); if (!wait--) { return -ETIMEDOUT; } nxsig_usleep(1000); } at24c_i2c_write(priv, at24addr, buf, AT24XX_PAGESIZE + AT24XX_ADDRSIZE); } 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_read_internal ****************************************************************************/ static ssize_t at24c_read_internal(FAR struct at24c_dev_s *priv, off_t offset, size_t nbytes, FAR uint8_t *buffer, uint8_t address) { uint8_t buf[AT24XX_ADDRSIZE]; uint16_t at24addr; uint16_t wait; finfo("offset: %lu nbytes: %lu address: %02x\n", (unsigned long)offset, (unsigned long)nbytes, address); /* "Random Read: A Random Read requires a dummy byte write sequence to * load in the data word address. Once the device address word and data * word address are clocked in and acknowledged by the EEPROM, the * microcontroller must generate another Start condition. The * microcontroller now initiates a current address read by sending a * device address with the read/write select bit high. The EEPROM * acknowledges the device address and serially clocks out the data word. * To end the random read sequence, the microcontroller does not respond * with a zero but does generate a Stop condition in the subsequent clock * cycle." * * A repeated START after the address is suggested, however, this simple * driver just performs the write as a sepate transfer with an additional, * unnecessary STOP. */ #if AT24XX_ADDRSIZE == 2 buf[1] = offset & 0xff; buf[0] = (offset >> 8) & 0xff; at24addr = address; #else buf[0] = offset & 0xff; at24addr = (address | ((offset >> 8) & 0x07)); #endif wait = CONFIG_AT24XX_TIMEOUT_MS; while (at24c_i2c_write(priv, at24addr, buf, AT24XX_ADDRSIZE) < 0) { finfo("wait\n"); if (!wait--) { return -ETIMEDOUT; } nxsig_usleep(1000); } /* Then transfer the following bytes */ at24c_i2c_read(priv, at24addr, buffer, nbytes); return nbytes; } /**************************************************************************** * 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; off_t offset; ssize_t nread; size_t i; #if CONFIG_AT24XX_MTD_BLOCKSIZE > AT24XX_PAGESIZE startblock *= (CONFIG_AT24XX_MTD_BLOCKSIZE / AT24XX_PAGESIZE); nblocks *= (CONFIG_AT24XX_MTD_BLOCKSIZE / AT24XX_PAGESIZE); #endif finfo("startblock: %08lx nblocks: %lu\n", (unsigned long)startblock, (unsigned long)nblocks); if (startblock >= priv->npages) { return 0; } if (startblock + nblocks > priv->npages) { nblocks = priv->npages - startblock; } /* Convert the access from startblock and number of blocks to a byte * offset and number of bytes. */ offset = startblock * priv->pagesize; /* Then perform the byte-oriented read for each block separately */ for (i = 0; i < nblocks; i++) { nread = at24c_read_internal(priv, offset, priv->pagesize, buffer, priv->addr); if (nread < 0) { return nread; } offset += priv->pagesize; 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 + AT24XX_ADDRSIZE]; uint16_t wait; #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; } finfo("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks); while (blocksleft-- > 0) { uint16_t offset = startblock * priv->pagesize; uint16_t at24addr; #if AT24XX_ADDRSIZE == 2 buf[1] = offset & 0xff; buf[0] = (offset >> 8) & 0xff; at24addr = priv->addr; #else buf[0] = offset & 0xff; at24addr = (priv->addr | ((offset >> 8) & 0x07)); #endif wait = CONFIG_AT24XX_TIMEOUT_MS; while (at24c_i2c_write(priv, at24addr, buf, AT24XX_ADDRSIZE) < 0) { finfo("wait\n"); if (!wait--) { return -ETIMEDOUT; } nxsig_usleep(1000); } memcpy(&buf[AT24XX_ADDRSIZE], buffer, priv->pagesize); at24c_i2c_write(priv, at24addr, buf, priv->pagesize + AT24XX_ADDRSIZE); 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_read ****************************************************************************/ static ssize_t at24c_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes, FAR uint8_t *buffer) { FAR struct at24c_dev_s *priv = (FAR struct at24c_dev_s *)dev; size_t memsize; uint8_t addr; finfo("offset: %lu nbytes: %lu\n", (unsigned long)offset, (unsigned long)nbytes); /* Don't permit reads beyond the end of the memory region */ #ifdef CONFIG_AT24XX_EXTENDED if (priv->extended) { memsize = CONFIG_AT24XX_EXTSIZE; } else #endif { memsize = AT24XX_NPAGES * AT24XX_PAGESIZE; } if (offset + nbytes > memsize) { /* Return 0 meaning end-of-file */ return 0; } /* Get the I2C address, converting it to the extended I2C if needed */ addr = priv->addr; #ifdef CONFIG_AT24XX_EXTENDED if (priv->extended) { addr |= 0x08; } #endif /* Then perform the byte-oriented read using common logic */ return at24c_read_internal(priv, offset, nbytes, buffer, addr); } /**************************************************************************** * 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 */ 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) { memset(geo, 0, sizeof(*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 kilobits and must be * scaled by 1024 / 8 */ #if CONFIG_AT24XX_MTD_BLOCKSIZE > AT24XX_PAGESIZE geo->blocksize = CONFIG_AT24XX_MTD_BLOCKSIZE; geo->erasesize = CONFIG_AT24XX_MTD_BLOCKSIZE; geo->neraseblocks = (CONFIG_AT24XX_SIZE * 1024 / 8) / CONFIG_AT24XX_MTD_BLOCKSIZE; #else geo->blocksize = priv->pagesize; geo->erasesize = priv->pagesize; geo->neraseblocks = priv->npages; #endif ret = OK; finfo("blocksize: %" PRId32 " erasesize: %" PRId32 " neraseblocks: %" PRId32 "\n", geo->blocksize, geo->erasesize, geo->neraseblocks); } } break; case BIOC_PARTINFO: { FAR struct partition_info_s *info = (FAR struct partition_info_s *)arg; if (info != NULL) { #if CONFIG_AT24XX_MTD_BLOCKSIZE > AT24XX_PAGESIZE info->numsectors = (CONFIG_AT24XX_SIZE * 1024 / 8) / CONFIG_AT24XX_MTD_BLOCKSIZE; info->sectorsize = CONFIG_AT24XX_MTD_BLOCKSIZE; #else info->numsectors = priv->npages; info->sectorsize = priv->pagesize; #endif info->startsector = 0; info->parent[0] = '\0'; ret = OK; } } break; case MTDIOC_BULKERASE: ret = at24c_eraseall(priv); break; #ifdef CONFIG_AT24XX_EXTENDED case MTDIOC_EXTENDED: priv->extended = (arg != 0); ret = OK; break; #endif default: ret = -ENOTTY; /* Bad command */ break; } return ret; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: at24c_initialize * * Description: * Create an initialized 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). * ****************************************************************************/ #ifdef CONFIG_AT24XX_MULTI FAR struct mtd_dev_s *at24c_initialize(FAR struct i2c_master_s *dev, uint8_t address) #else FAR struct mtd_dev_s *at24c_initialize(FAR struct i2c_master_s *dev) #endif { FAR struct at24c_dev_s *priv; #ifdef CONFIG_AT24XX_MULTI finfo("dev: %p address: %02x\n", dev, address); /* 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(0) definition) and so would * have to be extended to handle multiple FLASH parts on the same I2C bus. */ priv = kmm_zalloc(sizeof(struct at24c_dev_s)); if (priv == NULL) { ferr("ERROR: Failed to allocate device structure\n"); return NULL; } #else finfo("dev: %p\n", dev); /* If only a signal AT24 part is supported then a statically allocated * state structure is used. */ priv = &g_at24c; #endif if (!priv->initd) { /* Initialize the allocated structure */ #ifdef CONFIG_AT24XX_MULTI priv->addr = address; #else priv->addr = CONFIG_AT24XX_ADDR; #endif priv->pagesize = AT24XX_PAGESIZE; priv->npages = AT24XX_NPAGES; /* NOTE since the pre-allocated device structure lies in .bss, any * unsupported methods should have been nullified. */ priv->mtd.erase = at24c_erase; priv->mtd.bread = at24c_bread; priv->mtd.bwrite = at24c_bwrite; priv->mtd.read = at24c_read; priv->mtd.ioctl = at24c_ioctl; priv->mtd.name = "at24xx"; priv->dev = dev; priv->initd = true; } /* Return the implementation-specific state structure as the MTD device */ finfo("Return %p\n", priv); return (FAR struct mtd_dev_s *)priv; } /**************************************************************************** * Name: at24c_uninitialize * * Description: * Release resources held by an allocated MTD device instance. * Resources are only allocated for the case where multiple AT24xx * devices are support. * ****************************************************************************/ #ifdef CONFIG_AT24XX_MULTI void at24c_uninitialize(FAR struct mtd_dev_s *mtd) { FAR struct at24c_dev_s *priv = (FAR struct at24c_dev_s *)mtd; DEBUGASSERT(priv != NULL); #ifdef CONFIG_MTD_REGISTRATION /* Unregister the MTD with the procfs system if enabled */ mtd_unregister(&priv->mtd); #endif /* Free the MTD driver instance */ kmm_free(priv); } #endif /* CONFIG_AT24XX_MULTI */ #endif /* CONFIG_MTD_AT24XX */