| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * MTD layer for NAND Mapped-block Management (NMBM) |
| * |
| * Copyright (C) 2020 MediaTek Inc. All Rights Reserved. |
| * |
| * Author: Weijie Gao <weijie.gao@mediatek.com> |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/device.h> |
| #include <linux/slab.h> |
| #include <linux/interrupt.h> |
| #include <linux/sched.h> |
| #include <linux/wait.h> |
| #include <linux/spinlock.h> |
| #include <linux/mtd/mtd.h> |
| #include <linux/mtd/flashchip.h> |
| #include <linux/mtd/partitions.h> |
| #include <linux/of_platform.h> |
| #include <linux/kern_levels.h> |
| |
| #include "nmbm-private.h" |
| #include "nmbm-debug.h" |
| |
| #define NMBM_MAX_RATIO_DEFAULT 1 |
| #define NMBM_MAX_BLOCKS_DEFAULT 256 |
| |
| struct nmbm_mtd { |
| struct mtd_info upper; |
| struct mtd_info *lower; |
| |
| struct nmbm_instance *ni; |
| uint8_t *page_cache; |
| |
| flstate_t state; |
| spinlock_t lock; |
| wait_queue_head_t wq; |
| |
| struct device *dev; |
| struct list_head node; |
| }; |
| |
| struct list_head nmbm_devs; |
| static DEFINE_MUTEX(nmbm_devs_lock); |
| |
| static int nmbm_lower_read_page(void *arg, uint64_t addr, void *buf, void *oob, |
| enum nmbm_oob_mode mode) |
| { |
| struct nmbm_mtd *nm = arg; |
| struct mtd_oob_ops ops; |
| int ret; |
| |
| memset(&ops, 0, sizeof(ops)); |
| |
| switch (mode) { |
| case NMBM_MODE_PLACE_OOB: |
| ops.mode = MTD_OPS_PLACE_OOB; |
| break; |
| case NMBM_MODE_AUTO_OOB: |
| ops.mode = MTD_OPS_AUTO_OOB; |
| break; |
| case NMBM_MODE_RAW: |
| ops.mode = MTD_OPS_RAW; |
| break; |
| default: |
| pr_debug("%s: unsupported NMBM mode: %u\n", __func__, mode); |
| return -ENOTSUPP; |
| } |
| |
| if (buf) { |
| ops.datbuf = buf; |
| ops.len = nm->lower->writesize; |
| } |
| |
| if (oob) { |
| ops.oobbuf = oob; |
| ops.ooblen = mtd_oobavail(nm->lower, &ops); |
| } |
| |
| ret = mtd_read_oob(nm->lower, addr, &ops); |
| nm->upper.ecc_stats.corrected = nm->lower->ecc_stats.corrected; |
| nm->upper.ecc_stats.failed = nm->lower->ecc_stats.failed; |
| |
| /* Report error on failure (including ecc error) */ |
| if (ret < 0 && ret != -EUCLEAN) |
| return ret; |
| |
| /* |
| * Since mtd_read_oob() won't report exact bitflips, what we can know |
| * is whether bitflips exceeds the threshold. |
| * We want the -EUCLEAN to be passed to the upper layer, but not the |
| * error value itself. To achieve this, report bitflips above the |
| * threshold. |
| */ |
| |
| if (ret == -EUCLEAN) { |
| return min_t(u32, nm->lower->bitflip_threshold + 1, |
| nm->lower->ecc_strength); |
| } |
| |
| /* For bitflips less than the threshold, return 0 */ |
| return 0; |
| } |
| |
| static int nmbm_lower_write_page(void *arg, uint64_t addr, const void *buf, |
| const void *oob, enum nmbm_oob_mode mode) |
| { |
| struct nmbm_mtd *nm = arg; |
| struct mtd_oob_ops ops; |
| |
| memset(&ops, 0, sizeof(ops)); |
| |
| switch (mode) { |
| case NMBM_MODE_PLACE_OOB: |
| ops.mode = MTD_OPS_PLACE_OOB; |
| break; |
| case NMBM_MODE_AUTO_OOB: |
| ops.mode = MTD_OPS_AUTO_OOB; |
| break; |
| case NMBM_MODE_RAW: |
| ops.mode = MTD_OPS_RAW; |
| break; |
| default: |
| pr_debug("%s: unsupported NMBM mode: %u\n", __func__, mode); |
| return -ENOTSUPP; |
| } |
| |
| if (buf) { |
| ops.datbuf = (uint8_t *)buf; |
| ops.len = nm->lower->writesize; |
| } |
| |
| if (oob) { |
| ops.oobbuf = (uint8_t *)oob; |
| ops.ooblen = mtd_oobavail(nm->lower, &ops); |
| } |
| |
| return mtd_write_oob(nm->lower, addr, &ops); |
| } |
| |
| static int nmbm_lower_erase_block(void *arg, uint64_t addr) |
| { |
| struct nmbm_mtd *nm = arg; |
| struct erase_info ei; |
| |
| memset(&ei, 0, sizeof(ei)); |
| |
| ei.addr = addr; |
| ei.len = nm->lower->erasesize; |
| |
| return mtd_erase(nm->lower, &ei); |
| } |
| |
| static int nmbm_lower_is_bad_block(void *arg, uint64_t addr) |
| { |
| struct nmbm_mtd *nm = arg; |
| |
| return mtd_block_isbad(nm->lower, addr); |
| } |
| |
| static int nmbm_lower_mark_bad_block(void *arg, uint64_t addr) |
| { |
| struct nmbm_mtd *nm = arg; |
| |
| return mtd_block_markbad(nm->lower, addr); |
| } |
| |
| static void nmbm_lower_log(void *arg, enum nmbm_log_category level, |
| const char *fmt, va_list ap) |
| { |
| struct nmbm_mtd *nm = arg; |
| char *msg; |
| char *kl; |
| |
| msg = kvasprintf(GFP_KERNEL, fmt, ap); |
| if (!msg) { |
| dev_warn(nm->dev, "unable to print log\n"); |
| return; |
| } |
| |
| switch (level) { |
| case NMBM_LOG_DEBUG: |
| kl = KERN_DEBUG; |
| break; |
| case NMBM_LOG_WARN: |
| kl = KERN_WARNING; |
| break; |
| case NMBM_LOG_ERR: |
| kl = KERN_ERR; |
| break; |
| case NMBM_LOG_EMERG: |
| kl = KERN_EMERG; |
| break; |
| default: |
| kl = KERN_INFO ; |
| } |
| |
| dev_printk(kl, nm->dev, "%s", msg); |
| |
| kfree(msg); |
| } |
| |
| static int nmbm_get_device(struct nmbm_mtd *nm, int new_state) |
| { |
| DECLARE_WAITQUEUE(wait, current); |
| |
| retry: |
| spin_lock(&nm->lock); |
| |
| if (nm->state == FL_READY) { |
| nm->state = new_state; |
| spin_unlock(&nm->lock); |
| return 0; |
| } |
| |
| if (new_state == FL_PM_SUSPENDED) { |
| if (nm->state == FL_PM_SUSPENDED) { |
| spin_unlock(&nm->lock); |
| return 0; |
| } |
| } |
| |
| set_current_state(TASK_UNINTERRUPTIBLE); |
| add_wait_queue(&nm->wq, &wait); |
| spin_unlock(&nm->lock); |
| schedule(); |
| remove_wait_queue(&nm->wq, &wait); |
| goto retry; |
| } |
| |
| static void nmbm_release_device(struct nmbm_mtd *nm) |
| { |
| spin_lock(&nm->lock); |
| nm->state = FL_READY; |
| wake_up(&nm->wq); |
| spin_unlock(&nm->lock); |
| } |
| |
| static int nmbm_mtd_erase(struct mtd_info *mtd, struct erase_info *instr) |
| { |
| struct nmbm_mtd *nm = container_of(mtd, struct nmbm_mtd, upper); |
| int ret; |
| |
| nmbm_get_device(nm, FL_ERASING); |
| |
| ret = nmbm_erase_block_range(nm->ni, instr->addr, instr->len, |
| &instr->fail_addr); |
| |
| nmbm_release_device(nm); |
| |
| if (!ret) |
| return 0; |
| |
| return -EIO; |
| } |
| |
| static int nmbm_mtd_read_data(struct nmbm_mtd *nm, uint64_t addr, |
| struct mtd_oob_ops *ops, enum nmbm_oob_mode mode) |
| { |
| size_t len, ooblen, maxooblen, chklen; |
| uint32_t col, ooboffs; |
| uint8_t *datcache, *oobcache; |
| bool has_ecc_err = false; |
| int ret, max_bitflips = 0; |
| |
| col = addr & nm->lower->writesize_mask; |
| addr &= ~nm->lower->writesize_mask; |
| maxooblen = mtd_oobavail(nm->lower, ops); |
| ooboffs = ops->ooboffs; |
| ooblen = ops->ooblen; |
| len = ops->len; |
| |
| datcache = len ? nm->page_cache : NULL; |
| oobcache = ooblen ? nm->page_cache + nm->lower->writesize : NULL; |
| |
| ops->oobretlen = 0; |
| ops->retlen = 0; |
| |
| while (len || ooblen) { |
| ret = nmbm_read_single_page(nm->ni, addr, datcache, oobcache, |
| mode); |
| if (ret < 0 && ret != -EBADMSG) |
| return ret; |
| |
| /* Continue reading on ecc error */ |
| if (ret == -EBADMSG) |
| has_ecc_err = true; |
| |
| /* Record the maximum bitflips between pages */ |
| if (ret > max_bitflips) |
| max_bitflips = ret; |
| |
| if (len) { |
| /* Move data */ |
| chklen = nm->lower->writesize - col; |
| if (chklen > len) |
| chklen = len; |
| |
| memcpy(ops->datbuf + ops->retlen, datcache + col, |
| chklen); |
| len -= chklen; |
| col = 0; /* (col + chklen) % */ |
| ops->retlen += chklen; |
| } |
| |
| if (ooblen) { |
| /* Move oob */ |
| chklen = maxooblen - ooboffs; |
| if (chklen > ooblen) |
| chklen = ooblen; |
| |
| memcpy(ops->oobbuf + ops->oobretlen, oobcache + ooboffs, |
| chklen); |
| ooblen -= chklen; |
| ooboffs = 0; /* (ooboffs + chklen) % maxooblen; */ |
| ops->oobretlen += chklen; |
| } |
| |
| addr += nm->lower->writesize; |
| } |
| |
| if (has_ecc_err) |
| return -EBADMSG; |
| |
| return max_bitflips; |
| } |
| |
| static int nmbm_mtd_read_oob(struct mtd_info *mtd, loff_t from, |
| struct mtd_oob_ops *ops) |
| { |
| struct nmbm_mtd *nm = container_of(mtd, struct nmbm_mtd, upper); |
| uint32_t maxooblen; |
| enum nmbm_oob_mode mode; |
| int ret; |
| |
| if (!ops->oobbuf && !ops->datbuf) { |
| if (ops->ooblen || ops->len) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| switch (ops->mode) { |
| case MTD_OPS_PLACE_OOB: |
| mode = NMBM_MODE_PLACE_OOB; |
| break; |
| case MTD_OPS_AUTO_OOB: |
| mode = NMBM_MODE_AUTO_OOB; |
| break; |
| case MTD_OPS_RAW: |
| mode = NMBM_MODE_RAW; |
| break; |
| default: |
| pr_debug("%s: unsupported oob mode: %u\n", __func__, ops->mode); |
| return -ENOTSUPP; |
| } |
| |
| maxooblen = mtd_oobavail(mtd, ops); |
| |
| /* Do not allow read past end of device */ |
| if (ops->datbuf && (from + ops->len) > mtd->size) { |
| pr_debug("%s: attempt to read beyond end of device\n", |
| __func__); |
| return -EINVAL; |
| } |
| |
| if (!ops->oobbuf) { |
| nmbm_get_device(nm, FL_READING); |
| |
| /* Optimized for reading data only */ |
| ret = nmbm_read_range(nm->ni, from, ops->len, ops->datbuf, |
| mode, &ops->retlen); |
| |
| nmbm_release_device(nm); |
| |
| return ret; |
| } |
| |
| if (unlikely(ops->ooboffs >= maxooblen)) { |
| pr_debug("%s: attempt to start read outside oob\n", |
| __func__); |
| return -EINVAL; |
| } |
| |
| if (unlikely(from >= mtd->size || |
| ops->ooboffs + ops->ooblen > ((mtd->size >> mtd->writesize_shift) - |
| (from >> mtd->writesize_shift)) * maxooblen)) { |
| pr_debug("%s: attempt to read beyond end of device\n", |
| __func__); |
| return -EINVAL; |
| } |
| |
| nmbm_get_device(nm, FL_READING); |
| ret = nmbm_mtd_read_data(nm, from, ops, mode); |
| nmbm_release_device(nm); |
| |
| return ret; |
| } |
| |
| static int nmbm_mtd_write_data(struct nmbm_mtd *nm, uint64_t addr, |
| struct mtd_oob_ops *ops, enum nmbm_oob_mode mode) |
| { |
| size_t len, ooblen, maxooblen, chklen; |
| uint32_t col, ooboffs; |
| uint8_t *datcache, *oobcache; |
| int ret; |
| |
| col = addr & nm->lower->writesize_mask; |
| addr &= ~nm->lower->writesize_mask; |
| maxooblen = mtd_oobavail(nm->lower, ops); |
| ooboffs = ops->ooboffs; |
| ooblen = ops->ooblen; |
| len = ops->len; |
| |
| datcache = len ? nm->page_cache : NULL; |
| oobcache = ooblen ? nm->page_cache + nm->lower->writesize : NULL; |
| |
| ops->oobretlen = 0; |
| ops->retlen = 0; |
| |
| while (len || ooblen) { |
| if (len) { |
| /* Move data */ |
| chklen = nm->lower->writesize - col; |
| if (chklen > len) |
| chklen = len; |
| |
| memset(datcache, 0xff, col); |
| memcpy(datcache + col, ops->datbuf + ops->retlen, |
| chklen); |
| memset(datcache + col + chklen, 0xff, |
| nm->lower->writesize - col - chklen); |
| len -= chklen; |
| col = 0; /* (col + chklen) % */ |
| ops->retlen += chklen; |
| } |
| |
| if (ooblen) { |
| /* Move oob */ |
| chklen = maxooblen - ooboffs; |
| if (chklen > ooblen) |
| chklen = ooblen; |
| |
| memset(oobcache, 0xff, ooboffs); |
| memcpy(oobcache + ooboffs, |
| ops->oobbuf + ops->oobretlen, chklen); |
| memset(oobcache + ooboffs + chklen, 0xff, |
| nm->lower->oobsize - ooboffs - chklen); |
| ooblen -= chklen; |
| ooboffs = 0; /* (ooboffs + chklen) % maxooblen; */ |
| ops->oobretlen += chklen; |
| } |
| |
| ret = nmbm_write_single_page(nm->ni, addr, datcache, oobcache, |
| mode); |
| if (ret) |
| return ret; |
| |
| addr += nm->lower->writesize; |
| } |
| |
| return 0; |
| } |
| |
| static int nmbm_mtd_write_oob(struct mtd_info *mtd, loff_t to, |
| struct mtd_oob_ops *ops) |
| { |
| struct nmbm_mtd *nm = container_of(mtd, struct nmbm_mtd, upper); |
| enum nmbm_oob_mode mode; |
| uint32_t maxooblen; |
| int ret; |
| |
| if (!ops->oobbuf && !ops->datbuf) { |
| if (ops->ooblen || ops->len) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| switch (ops->mode) { |
| case MTD_OPS_PLACE_OOB: |
| mode = NMBM_MODE_PLACE_OOB; |
| break; |
| case MTD_OPS_AUTO_OOB: |
| mode = NMBM_MODE_AUTO_OOB; |
| break; |
| case MTD_OPS_RAW: |
| mode = NMBM_MODE_RAW; |
| break; |
| default: |
| pr_debug("%s: unsupported oob mode: %u\n", __func__, |
| ops->mode); |
| return -ENOTSUPP; |
| } |
| |
| maxooblen = mtd_oobavail(mtd, ops); |
| |
| /* Do not allow write past end of device */ |
| if (ops->datbuf && (to + ops->len) > mtd->size) { |
| pr_debug("%s: attempt to write beyond end of device\n", |
| __func__); |
| return -EINVAL; |
| } |
| |
| if (!ops->oobbuf) { |
| nmbm_get_device(nm, FL_WRITING); |
| |
| /* Optimized for writing data only */ |
| ret = nmbm_write_range(nm->ni, to, ops->len, ops->datbuf, |
| mode, &ops->retlen); |
| |
| nmbm_release_device(nm); |
| |
| return ret; |
| } |
| |
| if (unlikely(ops->ooboffs >= maxooblen)) { |
| pr_debug("%s: attempt to start write outside oob\n", |
| __func__); |
| return -EINVAL; |
| } |
| |
| if (unlikely(to >= mtd->size || |
| ops->ooboffs + ops->ooblen > ((mtd->size >> mtd->writesize_shift) - |
| (to >> mtd->writesize_shift)) * maxooblen)) { |
| pr_debug("%s: attempt to write beyond end of device\n", |
| __func__); |
| return -EINVAL; |
| } |
| |
| nmbm_get_device(nm, FL_WRITING); |
| ret = nmbm_mtd_write_data(nm, to, ops, mode); |
| nmbm_release_device(nm); |
| |
| return ret; |
| } |
| |
| static int nmbm_mtd_block_isbad(struct mtd_info *mtd, loff_t offs) |
| { |
| struct nmbm_mtd *nm = container_of(mtd, struct nmbm_mtd, upper); |
| int ret; |
| |
| nmbm_get_device(nm, FL_READING); |
| ret = nmbm_check_bad_block(nm->ni, offs); |
| nmbm_release_device(nm); |
| |
| return ret; |
| } |
| |
| static int nmbm_mtd_block_markbad(struct mtd_info *mtd, loff_t offs) |
| { |
| struct nmbm_mtd *nm = container_of(mtd, struct nmbm_mtd, upper); |
| int ret; |
| |
| nmbm_get_device(nm, FL_WRITING); |
| ret = nmbm_mark_bad_block(nm->ni, offs); |
| nmbm_release_device(nm); |
| |
| return ret; |
| } |
| |
| static void nmbm_mtd_shutdown(struct mtd_info *mtd) |
| { |
| struct nmbm_mtd *nm = container_of(mtd, struct nmbm_mtd, upper); |
| |
| nmbm_get_device(nm, FL_PM_SUSPENDED); |
| } |
| |
| static int nmbm_probe(struct platform_device *pdev) |
| { |
| struct device_node *mtd_np, *np = pdev->dev.of_node; |
| uint32_t max_ratio, max_reserved_blocks, alloc_size; |
| bool forced_create, empty_page_ecc_ok; |
| struct nmbm_lower_device nld; |
| struct mtd_info *lower, *mtd; |
| struct nmbm_mtd *nm; |
| const char *mtdname; |
| int ret; |
| |
| mtd_np = of_parse_phandle(np, "lower-mtd-device", 0); |
| if (mtd_np) { |
| lower = get_mtd_device_by_node(mtd_np); |
| if (!IS_ERR(lower)) |
| goto do_attach_mtd; |
| |
| dev_dbg(&pdev->dev, "failed to find mtd device by phandle\n"); |
| return -EPROBE_DEFER; |
| } |
| |
| ret = of_property_read_string(np, "lower-mtd-name", &mtdname); |
| if (!ret) { |
| lower = get_mtd_device_nm(mtdname); |
| if (!IS_ERR(lower)) |
| goto do_attach_mtd; |
| |
| dev_dbg(&pdev->dev, "failed to find mtd device by name '%s'\n", |
| mtdname); |
| return -EPROBE_DEFER; |
| } |
| |
| do_attach_mtd: |
| if (of_property_read_u32(np, "max-ratio", &max_ratio)) |
| max_ratio = NMBM_MAX_RATIO_DEFAULT; |
| |
| if (of_property_read_u32(np, "max-reserved-blocks", |
| &max_reserved_blocks)) |
| max_reserved_blocks = NMBM_MAX_BLOCKS_DEFAULT; |
| |
| forced_create = of_property_read_bool(np, "forced-create"); |
| empty_page_ecc_ok = of_property_read_bool(np, |
| "empty-page-ecc-protected"); |
| |
| memset(&nld, 0, sizeof(nld)); |
| |
| nld.flags = 0; |
| |
| if (forced_create) |
| nld.flags |= NMBM_F_CREATE; |
| |
| if (empty_page_ecc_ok) |
| nld.flags |= NMBM_F_EMPTY_PAGE_ECC_OK; |
| |
| nld.max_ratio = max_ratio; |
| nld.max_reserved_blocks = max_reserved_blocks; |
| |
| nld.size = lower->size; |
| nld.erasesize = lower->erasesize; |
| nld.writesize = lower->writesize; |
| nld.oobsize = lower->oobsize; |
| nld.oobavail = lower->oobavail; |
| |
| nld.read_page = nmbm_lower_read_page; |
| nld.write_page = nmbm_lower_write_page; |
| nld.erase_block = nmbm_lower_erase_block; |
| nld.is_bad_block = nmbm_lower_is_bad_block; |
| nld.mark_bad_block = nmbm_lower_mark_bad_block; |
| |
| nld.logprint = nmbm_lower_log; |
| |
| alloc_size = nmbm_calc_structure_size(&nld); |
| |
| nm = devm_kzalloc(&pdev->dev, sizeof(*nm) + alloc_size + |
| lower->writesize + lower->oobsize, GFP_KERNEL); |
| if (!nm) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| nm->ni = (void *)nm + sizeof(*nm); |
| nm->page_cache = (uint8_t *)nm->ni + alloc_size; |
| nm->lower = lower; |
| nm->dev = &pdev->dev; |
| |
| INIT_LIST_HEAD(&nm->node); |
| spin_lock_init(&nm->lock); |
| init_waitqueue_head(&nm->wq); |
| |
| nld.arg = nm; |
| |
| ret = nmbm_attach(&nld, nm->ni); |
| if (ret) |
| goto out; |
| |
| /* Initialize upper mtd */ |
| mtd = &nm->upper; |
| |
| mtd->owner = THIS_MODULE; |
| mtd->dev.parent = &pdev->dev; |
| mtd->type = lower->type; |
| mtd->flags = lower->flags; |
| |
| mtd->size = (uint64_t)nm->ni->data_block_count * lower->erasesize; |
| mtd->erasesize = lower->erasesize; |
| mtd->writesize = lower->writesize; |
| mtd->writebufsize = lower->writesize; |
| mtd->oobsize = lower->oobsize; |
| mtd->oobavail = lower->oobavail; |
| |
| mtd->erasesize_shift = lower->erasesize_shift; |
| mtd->writesize_shift = lower->writesize_shift; |
| mtd->erasesize_mask = lower->erasesize_mask; |
| mtd->writesize_mask = lower->writesize_mask; |
| |
| mtd->bitflip_threshold = lower->bitflip_threshold; |
| |
| mtd->ooblayout = lower->ooblayout; |
| |
| mtd->ecc_step_size = lower->ecc_step_size; |
| mtd->ecc_strength = lower->ecc_strength; |
| |
| mtd->numeraseregions = lower->numeraseregions; |
| mtd->eraseregions = lower->eraseregions; |
| |
| mtd->_erase = nmbm_mtd_erase; |
| mtd->_read_oob = nmbm_mtd_read_oob; |
| mtd->_write_oob = nmbm_mtd_write_oob; |
| mtd->_block_isbad = nmbm_mtd_block_isbad; |
| mtd->_block_markbad = nmbm_mtd_block_markbad; |
| mtd->_reboot = nmbm_mtd_shutdown; |
| |
| mtd_set_of_node(mtd, np); |
| |
| ret = mtd_device_register(mtd, NULL, 0); |
| if (ret) { |
| dev_err(&pdev->dev, "failed to register mtd device\n"); |
| nmbm_detach(nm->ni); |
| goto out; |
| } |
| |
| platform_set_drvdata(pdev, nm); |
| |
| mutex_lock(&nmbm_devs_lock); |
| list_add_tail(&nm->node, &nmbm_devs); |
| mutex_unlock(&nmbm_devs_lock); |
| |
| return 0; |
| |
| out: |
| if (nm) |
| devm_kfree(&pdev->dev, nm); |
| |
| put_mtd_device(lower); |
| |
| return ret; |
| } |
| |
| static int nmbm_remove(struct platform_device *pdev) |
| { |
| struct nmbm_mtd *nm = platform_get_drvdata(pdev); |
| struct mtd_info *lower = nm->lower; |
| int ret; |
| |
| ret = mtd_device_unregister(&nm->upper); |
| if (ret) |
| return ret; |
| |
| nmbm_detach(nm->ni); |
| |
| mutex_lock(&nmbm_devs_lock); |
| list_add_tail(&nm->node, &nmbm_devs); |
| mutex_unlock(&nmbm_devs_lock); |
| |
| devm_kfree(&pdev->dev, nm); |
| |
| put_mtd_device(lower); |
| |
| platform_set_drvdata(pdev, NULL); |
| |
| return 0; |
| } |
| |
| static const struct of_device_id nmbm_ids[] = { |
| { .compatible = "generic,nmbm" }, |
| { }, |
| }; |
| |
| MODULE_DEVICE_TABLE(of, nmbm_ids); |
| |
| static struct platform_driver nmbm_driver = { |
| .probe = nmbm_probe, |
| .remove = nmbm_remove, |
| .driver = { |
| .name = "nmbm", |
| .of_match_table = nmbm_ids, |
| }, |
| }; |
| |
| static int __init nmbm_init(void) |
| { |
| int ret; |
| |
| INIT_LIST_HEAD(&nmbm_devs); |
| |
| ret = platform_driver_register(&nmbm_driver); |
| if (ret) { |
| pr_err("failed to register nmbm driver\n"); |
| return ret; |
| } |
| |
| return 0; |
| } |
| module_init(nmbm_init); |
| |
| static void __exit nmbm_exit(void) |
| { |
| platform_driver_unregister(&nmbm_driver); |
| } |
| module_exit(nmbm_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Weijie Gao <weijie.gao@mediatek.com>"); |
| MODULE_DESCRIPTION("NAND mapping block management"); |