diff options
Diffstat (limited to 'drivers/mtd/devices/at91_dataflash26.c')
| -rw-r--r-- | drivers/mtd/devices/at91_dataflash26.c | 485 |
1 files changed, 0 insertions, 485 deletions
diff --git a/drivers/mtd/devices/at91_dataflash26.c b/drivers/mtd/devices/at91_dataflash26.c deleted file mode 100644 index 64ce37f..0000000 --- a/drivers/mtd/devices/at91_dataflash26.c +++ /dev/null @@ -1,485 +0,0 @@ -/* - * Atmel DataFlash driver for Atmel AT91RM9200 (Thunder) - * This is a largely modified version of at91_dataflash.c that - * supports AT26xxx dataflash chips. The original driver supports - * AT45xxx chips. - * - * Note: This driver was only tested with an AT26F004. It should be - * easy to make it work with other AT26xxx dataflash devices, though. - * - * Copyright (C) 2007 Hans J. Koch <hjk@linutronix.de> - * original Copyright (C) SAN People (Pty) Ltd - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * version 2 as published by the Free Software Foundation. -*/ - -#include <linux/config.h> -#include <linux/module.h> -#include <linux/init.h> -#include <linux/mtd/mtd.h> - -#include <asm/arch/at91_spi.h> - -#define DATAFLASH_MAX_DEVICES 4 /* max number of dataflash devices */ - -#define MANUFACTURER_ID_ATMEL 0x1F - -/* command codes */ - -#define AT26_OP_READ_STATUS 0x05 -#define AT26_OP_READ_DEV_ID 0x9F -#define AT26_OP_ERASE_PAGE_4K 0x20 -#define AT26_OP_READ_ARRAY_FAST 0x0B -#define AT26_OP_SEQUENTIAL_WRITE 0xAF -#define AT26_OP_WRITE_ENABLE 0x06 -#define AT26_OP_WRITE_DISABLE 0x04 -#define AT26_OP_SECTOR_PROTECT 0x36 -#define AT26_OP_SECTOR_UNPROTECT 0x39 - -/* status register bits */ - -#define AT26_STATUS_BUSY 0x01 -#define AT26_STATUS_WRITE_ENABLE 0x02 - -struct dataflash_local -{ - int spi; /* SPI chip-select number */ - unsigned int page_size; /* number of bytes per page */ -}; - - -/* Detected DataFlash devices */ -static struct mtd_info* mtd_devices[DATAFLASH_MAX_DEVICES]; -static int nr_devices = 0; - -/* Allocate a single SPI transfer descriptor. We're assuming that if multiple - SPI transfers occur at the same time, spi_access_bus() will serialize them. - If this is not valid, then either (i) each dataflash 'priv' structure - needs it's own transfer descriptor, (ii) we lock this one, or (iii) use - another mechanism. */ -static struct spi_transfer_list* spi_transfer_desc; - -/* - * Perform a SPI transfer to access the DataFlash device. - */ -static int do_spi_transfer(int nr, char* tx, int tx_len, char* rx, int rx_len, - char* txnext, int txnext_len, char* rxnext, int rxnext_len) -{ - struct spi_transfer_list* list = spi_transfer_desc; - - list->tx[0] = tx; list->txlen[0] = tx_len; - list->rx[0] = rx; list->rxlen[0] = rx_len; - - list->tx[1] = txnext; list->txlen[1] = txnext_len; - list->rx[1] = rxnext; list->rxlen[1] = rxnext_len; - - list->nr_transfers = nr; - /* Note: spi_transfer() always returns 0, there are no error checks */ - return spi_transfer(list); -} - -/* - * Return the status of the DataFlash device. - */ -static unsigned char at91_dataflash26_status(void) -{ - unsigned char command[2]; - - command[0] = AT26_OP_READ_STATUS; - command[1] = 0; - - do_spi_transfer(1, command, 2, command, 2, NULL, 0, NULL, 0); - - return command[1]; -} - -/* - * Poll the DataFlash device until it is READY. - */ -static unsigned char at91_dataflash26_waitready(void) -{ - unsigned char status; - - while (1) { - status = at91_dataflash26_status(); - if (!(status & AT26_STATUS_BUSY)) - return status; - } -} - -/* - * Enable/disable write access - */ - static void at91_dataflash26_write_enable(int enable) -{ - unsigned char cmd[2]; - - DEBUG(MTD_DEBUG_LEVEL3, "write_enable: enable=%i\n", enable); - - if (enable) - cmd[0] = AT26_OP_WRITE_ENABLE; - else - cmd[0] = AT26_OP_WRITE_DISABLE; - cmd[1] = 0; - - do_spi_transfer(1, cmd, 2, cmd, 2, NULL, 0, NULL, 0); -} - -/* - * Protect/unprotect sector - */ - static void at91_dataflash26_sector_protect(loff_t addr, int protect) -{ - unsigned char cmd[4]; - - DEBUG(MTD_DEBUG_LEVEL3, "sector_protect: addr=0x%06x prot=%d\n", - addr, protect); - - if (protect) - cmd[0] = AT26_OP_SECTOR_PROTECT; - else - cmd[0] = AT26_OP_SECTOR_UNPROTECT; - cmd[1] = (addr & 0x00FF0000) >> 16; - cmd[2] = (addr & 0x0000FF00) >> 8; - cmd[3] = (addr & 0x000000FF); - - do_spi_transfer(1, cmd, 4, cmd, 4, NULL, 0, NULL, 0); -} - -/* - * Erase blocks of flash. - */ -static int at91_dataflash26_erase(struct mtd_info *mtd, - struct erase_info *instr) -{ - struct dataflash_local *priv = (struct dataflash_local *) mtd->priv; - unsigned char cmd[4]; - - DEBUG(MTD_DEBUG_LEVEL1, "dataflash_erase: addr=0x%06x len=%i\n", - instr->addr, instr->len); - - /* Sanity checks */ - if (priv->page_size != 4096) - return -EINVAL; /* Can't handle other sizes at the moment */ - - if ( ((instr->len % mtd->erasesize) != 0) - || ((instr->len % priv->page_size) != 0) - || ((instr->addr % priv->page_size) != 0) - || ((instr->addr + instr->len) > mtd->size)) - return -EINVAL; - - spi_access_bus(priv->spi); - - while (instr->len > 0) { - at91_dataflash26_write_enable(1); - at91_dataflash26_sector_protect(instr->addr, 0); - at91_dataflash26_write_enable(1); - cmd[0] = AT26_OP_ERASE_PAGE_4K; - cmd[1] = (instr->addr & 0x00FF0000) >> 16; - cmd[2] = (instr->addr & 0x0000FF00) >> 8; - cmd[3] = (instr->addr & 0x000000FF); - - DEBUG(MTD_DEBUG_LEVEL3, "ERASE: (0x%02x) 0x%02x 0x%02x" - "0x%02x\n", - cmd[0], cmd[1], cmd[2], cmd[3]); - - do_spi_transfer(1, cmd, 4, cmd, 4, NULL, 0, NULL, 0); - at91_dataflash26_waitready(); - - instr->addr += priv->page_size; /* next page */ - instr->len -= priv->page_size; - } - - at91_dataflash26_write_enable(0); - spi_release_bus(priv->spi); - - /* Inform MTD subsystem that erase is complete */ - instr->state = MTD_ERASE_DONE; - if (instr->callback) - instr->callback(instr); - - return 0; -} - -/* - * Read from the DataFlash device. - * from : Start offset in flash device - * len : Number of bytes to read - * retlen : Number of bytes actually read - * buf : Buffer that will receive data - */ -static int at91_dataflash26_read(struct mtd_info *mtd, loff_t from, size_t len, - size_t *retlen, u_char *buf) -{ - struct dataflash_local *priv = (struct dataflash_local *) mtd->priv; - unsigned char cmd[5]; - - DEBUG(MTD_DEBUG_LEVEL1, "dataflash_read: %lli .. %lli\n", - from, from+len); - - *retlen = 0; - - /* Sanity checks */ - if (!len) - return 0; - if (from + len > mtd->size) - return -EINVAL; - - cmd[0] = AT26_OP_READ_ARRAY_FAST; - cmd[1] = (from & 0x00FF0000) >> 16; - cmd[2] = (from & 0x0000FF00) >> 8; - cmd[3] = (from & 0x000000FF); - /* cmd[4] is a "Don't care" byte */ - - DEBUG(MTD_DEBUG_LEVEL3, "READ: (0x%02x) 0x%02x 0x%02x 0x%02x\n", - cmd[0], cmd[1], cmd[2], cmd[3]); - - spi_access_bus(priv->spi); - do_spi_transfer(2, cmd, 5, cmd, 5, buf, len, buf, len); - spi_release_bus(priv->spi); - - *retlen = len; - return 0; -} - -/* - * Write to the DataFlash device. - * to : Start offset in flash device - * len : Number of bytes to write - * retlen : Number of bytes actually written - * buf : Buffer containing the data - */ -static int at91_dataflash26_write(struct mtd_info *mtd, loff_t to, size_t len, - size_t *retlen, const u_char *buf) -{ - struct dataflash_local *priv = (struct dataflash_local *) mtd->priv; - unsigned int addr, buf_index = 0; - int ret = -EIO, sector, last_sector; - unsigned char status, cmd[5]; - - DEBUG(MTD_DEBUG_LEVEL1, "dataflash_write: %lli .. %lli\n", to, to+len); - - *retlen = 0; - - /* Sanity checks */ - if (!len) - return 0; - if (to + len > mtd->size) - return -EINVAL; - - spi_access_bus(priv->spi); - - addr = to; - last_sector = -1; - - while (buf_index < len) { - sector = addr / priv->page_size; - /* Write first byte if a new sector begins */ - if (sector != last_sector) { - at91_dataflash26_write_enable(1); - at91_dataflash26_sector_protect(addr, 0); - at91_dataflash26_write_enable(1); - - /* Program first byte of a new sector */ - cmd[0] = AT26_OP_SEQUENTIAL_WRITE; - cmd[1] = (addr & 0x00FF0000) >> 16; - cmd[2] = (addr & 0x0000FF00) >> 8; - cmd[3] = (addr & 0x000000FF); - cmd[4] = buf[buf_index++]; - do_spi_transfer(1, cmd, 5, cmd, 5, NULL, 0, NULL, 0); - status = at91_dataflash26_waitready(); - addr++; - /* On write errors, the chip resets the write enable - flag. This also happens after the last byte of a - sector is successfully programmed. */ - if ( ( !(status & AT26_STATUS_WRITE_ENABLE)) - && ((addr % priv->page_size) != 0) ) { - DEBUG(MTD_DEBUG_LEVEL1, - "write error1: addr=0x%06x, " - "status=0x%02x\n", addr, status); - goto write_err; - } - (*retlen)++; - last_sector = sector; - } - - /* Write subsequent bytes in the same sector */ - cmd[0] = AT26_OP_SEQUENTIAL_WRITE; - cmd[1] = buf[buf_index++]; - do_spi_transfer(1, cmd, 2, cmd, 2, NULL, 0, NULL, 0); - status = at91_dataflash26_waitready(); - addr++; - - if ( ( !(status & AT26_STATUS_WRITE_ENABLE)) - && ((addr % priv->page_size) != 0) ) { - DEBUG(MTD_DEBUG_LEVEL1, "write error2: addr=0x%06x, " - "status=0x%02x\n", addr, status); - goto write_err; - } - - (*retlen)++; - } - - ret = 0; - at91_dataflash26_write_enable(0); -write_err: - spi_release_bus(priv->spi); - return ret; -} - -/* - * Initialize and register DataFlash device with MTD subsystem. - */ -static int __init add_dataflash(int channel, char *name, int nr_pages, - int pagesize) -{ - struct mtd_info *device; - struct dataflash_local *priv; - - if (nr_devices >= DATAFLASH_MAX_DEVICES) { - printk(KERN_ERR "at91_dataflash26: Too many devices " - "detected\n"); - return 0; - } - - device = kzalloc(sizeof(struct mtd_info) + strlen(name) + 8, - GFP_KERNEL); - if (!device) - return -ENOMEM; - - device->name = (char *)&device[1]; - sprintf(device->name, "%s.spi%d", name, channel); - device->size = nr_pages * pagesize; - device->erasesize = pagesize; - device->owner = THIS_MODULE; - device->type = MTD_DATAFLASH; - device->flags = MTD_CAP_NORFLASH; - device->erase = at91_dataflash26_erase; - device->read = at91_dataflash26_read; - device->write = at91_dataflash26_write; - - priv = (struct dataflash_local *)kzalloc(sizeof(struct dataflash_local), - GFP_KERNEL); - if (!priv) { - kfree(device); - return -ENOMEM; - } - - priv->spi = channel; - priv->page_size = pagesize; - device->priv = priv; - - mtd_devices[nr_devices] = device; - nr_devices++; - printk(KERN_INFO "at91_dataflash26: %s detected [spi%i] (%i bytes)\n", - name, channel, device->size); - - return add_mtd_device(device); -} - -/* - * Detect and initialize DataFlash device connected to specified SPI channel. - * - */ - -struct dataflash26_types { - unsigned char id0; - unsigned char id1; - char *name; - int pagesize; - int nr_pages; -}; - -struct dataflash26_types df26_types[] = { - { - .id0 = 0x04, - .id1 = 0x00, - .name = "AT26F004", - .pagesize = 4096, - .nr_pages = 128, - }, - { - .id0 = 0x45, - .id1 = 0x01, - .name = "AT26DF081A", /* Not tested ! */ - .pagesize = 4096, - .nr_pages = 256, - }, -}; - -static int __init at91_dataflash26_detect(int channel) -{ - unsigned char status, cmd[5]; - int i; - - spi_access_bus(channel); - status = at91_dataflash26_status(); - - if (status == 0 || status == 0xff) { - printk(KERN_ERR "at91_dataflash26_detect: status error %d\n", - status); - spi_release_bus(channel); - return -ENODEV; - } - - cmd[0] = AT26_OP_READ_DEV_ID; - do_spi_transfer(1, cmd, 5, cmd, 5, NULL, 0, NULL, 0); - spi_release_bus(channel); - - if (cmd[1] != MANUFACTURER_ID_ATMEL) - return -ENODEV; - - for (i = 0; i < ARRAY_SIZE(df26_types); i++) { - if ( cmd[2] == df26_types[i].id0 - && cmd[3] == df26_types[i].id1) - return add_dataflash(channel, - df26_types[i].name, - df26_types[i].nr_pages, - df26_types[i].pagesize); - } - - printk(KERN_ERR "at91_dataflash26_detect: Unsupported device " - "(0x%02x/0x%02x)\n", cmd[2], cmd[3]); - return -ENODEV; -} - -static int __init at91_dataflash26_init(void) -{ - spi_transfer_desc = kmalloc(sizeof(struct spi_transfer_list), - GFP_KERNEL); - if (!spi_transfer_desc) - return -ENOMEM; - - /* DataFlash (SPI chip select 0) */ - at91_dataflash26_detect(0); - -#ifdef CONFIG_MTD_AT91_DATAFLASH_CARD - /* DataFlash card (SPI chip select 3) */ - at91_dataflash26_detect(3); -#endif - return 0; -} - -static void __exit at91_dataflash26_exit(void) -{ - int i; - - for (i = 0; i < DATAFLASH_MAX_DEVICES; i++) { - if (mtd_devices[i]) { - del_mtd_device(mtd_devices[i]); - kfree(mtd_devices[i]->priv); - kfree(mtd_devices[i]); - } - } - nr_devices = 0; - kfree(spi_transfer_desc); -} - -module_init(at91_dataflash26_init); -module_exit(at91_dataflash26_exit); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Hans J. Koch"); -MODULE_DESCRIPTION("DataFlash AT26xxx driver for Atmel AT91RM9200"); |