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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/mtd/devices/sst25l.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mtd/devices/sst25l.c')
-rw-r--r-- | drivers/mtd/devices/sst25l.c | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/drivers/mtd/devices/sst25l.c b/drivers/mtd/devices/sst25l.c new file mode 100644 index 0000000000..8813994ce9 --- /dev/null +++ b/drivers/mtd/devices/sst25l.c @@ -0,0 +1,421 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * sst25l.c + * + * Driver for SST25L SPI Flash chips + * + * Copyright © 2009 Bluewater Systems Ltd + * Author: Andre Renaud <andre@bluewatersys.com> + * Author: Ryan Mallon + * + * Based on m25p80.c + */ + +#include <linux/module.h> +#include <linux/device.h> +#include <linux/mutex.h> +#include <linux/interrupt.h> +#include <linux/slab.h> +#include <linux/sched.h> + +#include <linux/mtd/mtd.h> +#include <linux/mtd/partitions.h> + +#include <linux/spi/spi.h> +#include <linux/spi/flash.h> + +/* Erases can take up to 3 seconds! */ +#define MAX_READY_WAIT_JIFFIES msecs_to_jiffies(3000) + +#define SST25L_CMD_WRSR 0x01 /* Write status register */ +#define SST25L_CMD_WRDI 0x04 /* Write disable */ +#define SST25L_CMD_RDSR 0x05 /* Read status register */ +#define SST25L_CMD_WREN 0x06 /* Write enable */ +#define SST25L_CMD_READ 0x03 /* High speed read */ + +#define SST25L_CMD_EWSR 0x50 /* Enable write status register */ +#define SST25L_CMD_SECTOR_ERASE 0x20 /* Erase sector */ +#define SST25L_CMD_READ_ID 0x90 /* Read device ID */ +#define SST25L_CMD_AAI_PROGRAM 0xaf /* Auto address increment */ + +#define SST25L_STATUS_BUSY (1 << 0) /* Chip is busy */ +#define SST25L_STATUS_WREN (1 << 1) /* Write enabled */ +#define SST25L_STATUS_BP0 (1 << 2) /* Block protection 0 */ +#define SST25L_STATUS_BP1 (1 << 3) /* Block protection 1 */ + +struct sst25l_flash { + struct spi_device *spi; + struct mutex lock; + struct mtd_info mtd; +}; + +struct flash_info { + const char *name; + uint16_t device_id; + unsigned page_size; + unsigned nr_pages; + unsigned erase_size; +}; + +#define to_sst25l_flash(x) container_of(x, struct sst25l_flash, mtd) + +static struct flash_info sst25l_flash_info[] = { + {"sst25lf020a", 0xbf43, 256, 1024, 4096}, + {"sst25lf040a", 0xbf44, 256, 2048, 4096}, +}; + +static int sst25l_status(struct sst25l_flash *flash, int *status) +{ + struct spi_message m; + struct spi_transfer t; + unsigned char cmd_resp[2]; + int err; + + spi_message_init(&m); + memset(&t, 0, sizeof(struct spi_transfer)); + + cmd_resp[0] = SST25L_CMD_RDSR; + cmd_resp[1] = 0xff; + t.tx_buf = cmd_resp; + t.rx_buf = cmd_resp; + t.len = sizeof(cmd_resp); + spi_message_add_tail(&t, &m); + err = spi_sync(flash->spi, &m); + if (err < 0) + return err; + + *status = cmd_resp[1]; + return 0; +} + +static int sst25l_write_enable(struct sst25l_flash *flash, int enable) +{ + unsigned char command[2]; + int status, err; + + command[0] = enable ? SST25L_CMD_WREN : SST25L_CMD_WRDI; + err = spi_write(flash->spi, command, 1); + if (err) + return err; + + command[0] = SST25L_CMD_EWSR; + err = spi_write(flash->spi, command, 1); + if (err) + return err; + + command[0] = SST25L_CMD_WRSR; + command[1] = enable ? 0 : SST25L_STATUS_BP0 | SST25L_STATUS_BP1; + err = spi_write(flash->spi, command, 2); + if (err) + return err; + + if (enable) { + err = sst25l_status(flash, &status); + if (err) + return err; + if (!(status & SST25L_STATUS_WREN)) + return -EROFS; + } + + return 0; +} + +static int sst25l_wait_till_ready(struct sst25l_flash *flash) +{ + unsigned long deadline; + int status, err; + + deadline = jiffies + MAX_READY_WAIT_JIFFIES; + do { + err = sst25l_status(flash, &status); + if (err) + return err; + if (!(status & SST25L_STATUS_BUSY)) + return 0; + + cond_resched(); + } while (!time_after_eq(jiffies, deadline)); + + return -ETIMEDOUT; +} + +static int sst25l_erase_sector(struct sst25l_flash *flash, uint32_t offset) +{ + unsigned char command[4]; + int err; + + err = sst25l_write_enable(flash, 1); + if (err) + return err; + + command[0] = SST25L_CMD_SECTOR_ERASE; + command[1] = offset >> 16; + command[2] = offset >> 8; + command[3] = offset; + err = spi_write(flash->spi, command, 4); + if (err) + return err; + + err = sst25l_wait_till_ready(flash); + if (err) + return err; + + return sst25l_write_enable(flash, 0); +} + +static int sst25l_erase(struct mtd_info *mtd, struct erase_info *instr) +{ + struct sst25l_flash *flash = to_sst25l_flash(mtd); + uint32_t addr, end; + int err; + + /* Sanity checks */ + if ((uint32_t)instr->len % mtd->erasesize) + return -EINVAL; + + if ((uint32_t)instr->addr % mtd->erasesize) + return -EINVAL; + + addr = instr->addr; + end = addr + instr->len; + + mutex_lock(&flash->lock); + + err = sst25l_wait_till_ready(flash); + if (err) { + mutex_unlock(&flash->lock); + return err; + } + + while (addr < end) { + err = sst25l_erase_sector(flash, addr); + if (err) { + mutex_unlock(&flash->lock); + dev_err(&flash->spi->dev, "Erase failed\n"); + return err; + } + + addr += mtd->erasesize; + } + + mutex_unlock(&flash->lock); + + return 0; +} + +static int sst25l_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, unsigned char *buf) +{ + struct sst25l_flash *flash = to_sst25l_flash(mtd); + struct spi_transfer transfer[2]; + struct spi_message message; + unsigned char command[4]; + int ret; + + spi_message_init(&message); + memset(&transfer, 0, sizeof(transfer)); + + command[0] = SST25L_CMD_READ; + command[1] = from >> 16; + command[2] = from >> 8; + command[3] = from; + + transfer[0].tx_buf = command; + transfer[0].len = sizeof(command); + spi_message_add_tail(&transfer[0], &message); + + transfer[1].rx_buf = buf; + transfer[1].len = len; + spi_message_add_tail(&transfer[1], &message); + + mutex_lock(&flash->lock); + + /* Wait for previous write/erase to complete */ + ret = sst25l_wait_till_ready(flash); + if (ret) { + mutex_unlock(&flash->lock); + return ret; + } + + spi_sync(flash->spi, &message); + + if (retlen && message.actual_length > sizeof(command)) + *retlen += message.actual_length - sizeof(command); + + mutex_unlock(&flash->lock); + return 0; +} + +static int sst25l_write(struct mtd_info *mtd, loff_t to, size_t len, + size_t *retlen, const unsigned char *buf) +{ + struct sst25l_flash *flash = to_sst25l_flash(mtd); + int i, j, ret, bytes, copied = 0; + unsigned char command[5]; + + if ((uint32_t)to % mtd->writesize) + return -EINVAL; + + mutex_lock(&flash->lock); + + ret = sst25l_write_enable(flash, 1); + if (ret) + goto out; + + for (i = 0; i < len; i += mtd->writesize) { + ret = sst25l_wait_till_ready(flash); + if (ret) + goto out; + + /* Write the first byte of the page */ + command[0] = SST25L_CMD_AAI_PROGRAM; + command[1] = (to + i) >> 16; + command[2] = (to + i) >> 8; + command[3] = (to + i); + command[4] = buf[i]; + ret = spi_write(flash->spi, command, 5); + if (ret < 0) + goto out; + copied++; + + /* + * Write the remaining bytes using auto address + * increment mode + */ + bytes = min_t(uint32_t, mtd->writesize, len - i); + for (j = 1; j < bytes; j++, copied++) { + ret = sst25l_wait_till_ready(flash); + if (ret) + goto out; + + command[1] = buf[i + j]; + ret = spi_write(flash->spi, command, 2); + if (ret) + goto out; + } + } + +out: + ret = sst25l_write_enable(flash, 0); + + if (retlen) + *retlen = copied; + + mutex_unlock(&flash->lock); + return ret; +} + +static struct flash_info *sst25l_match_device(struct spi_device *spi) +{ + struct flash_info *flash_info = NULL; + struct spi_message m; + struct spi_transfer t; + unsigned char cmd_resp[6]; + int i, err; + uint16_t id; + + spi_message_init(&m); + memset(&t, 0, sizeof(struct spi_transfer)); + + cmd_resp[0] = SST25L_CMD_READ_ID; + cmd_resp[1] = 0; + cmd_resp[2] = 0; + cmd_resp[3] = 0; + cmd_resp[4] = 0xff; + cmd_resp[5] = 0xff; + t.tx_buf = cmd_resp; + t.rx_buf = cmd_resp; + t.len = sizeof(cmd_resp); + spi_message_add_tail(&t, &m); + err = spi_sync(spi, &m); + if (err < 0) { + dev_err(&spi->dev, "error reading device id\n"); + return NULL; + } + + id = (cmd_resp[4] << 8) | cmd_resp[5]; + + for (i = 0; i < ARRAY_SIZE(sst25l_flash_info); i++) + if (sst25l_flash_info[i].device_id == id) + flash_info = &sst25l_flash_info[i]; + + if (!flash_info) + dev_err(&spi->dev, "unknown id %.4x\n", id); + + return flash_info; +} + +static int sst25l_probe(struct spi_device *spi) +{ + struct flash_info *flash_info; + struct sst25l_flash *flash; + struct flash_platform_data *data; + int ret; + + flash_info = sst25l_match_device(spi); + if (!flash_info) + return -ENODEV; + + flash = devm_kzalloc(&spi->dev, sizeof(*flash), GFP_KERNEL); + if (!flash) + return -ENOMEM; + + flash->spi = spi; + mutex_init(&flash->lock); + spi_set_drvdata(spi, flash); + + data = dev_get_platdata(&spi->dev); + if (data && data->name) + flash->mtd.name = data->name; + + flash->mtd.dev.parent = &spi->dev; + flash->mtd.type = MTD_NORFLASH; + flash->mtd.flags = MTD_CAP_NORFLASH; + flash->mtd.erasesize = flash_info->erase_size; + flash->mtd.writesize = flash_info->page_size; + flash->mtd.writebufsize = flash_info->page_size; + flash->mtd.size = flash_info->page_size * flash_info->nr_pages; + flash->mtd._erase = sst25l_erase; + flash->mtd._read = sst25l_read; + flash->mtd._write = sst25l_write; + + dev_info(&spi->dev, "%s (%lld KiB)\n", flash_info->name, + (long long)flash->mtd.size >> 10); + + pr_debug("mtd .name = %s, .size = 0x%llx (%lldMiB) " + ".erasesize = 0x%.8x (%uKiB) .numeraseregions = %d\n", + flash->mtd.name, + (long long)flash->mtd.size, (long long)(flash->mtd.size >> 20), + flash->mtd.erasesize, flash->mtd.erasesize / 1024, + flash->mtd.numeraseregions); + + + ret = mtd_device_register(&flash->mtd, data ? data->parts : NULL, + data ? data->nr_parts : 0); + if (ret) + return -ENODEV; + + return 0; +} + +static void sst25l_remove(struct spi_device *spi) +{ + struct sst25l_flash *flash = spi_get_drvdata(spi); + + WARN_ON(mtd_device_unregister(&flash->mtd)); +} + +static struct spi_driver sst25l_driver = { + .driver = { + .name = "sst25l", + }, + .probe = sst25l_probe, + .remove = sst25l_remove, +}; + +module_spi_driver(sst25l_driver); + +MODULE_DESCRIPTION("MTD SPI driver for SST25L Flash chips"); +MODULE_AUTHOR("Andre Renaud <andre@bluewatersys.com>, " + "Ryan Mallon"); +MODULE_LICENSE("GPL"); |