From 7014568bad55c20b7ee4f439d78c9e875912d51f Mon Sep 17 00:00:00 2001 From: Vitaly Wool Date: Fri, 3 Nov 2006 18:20:38 +0300 Subject: [MTD] [NAND] remove len/ooblen confusion. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As was discussed between Ricard Wanderlöf, David Woodhouse, Artem Bityutskiy and me, the current API for reading/writing OOB is confusing. The thing that introduces confusion is the need to specify ops.len together with ops.ooblen for reads/writes that concern only OOB not data area. So, ops.len is overloaded: when ops.datbuf != NULL it serves to specify the length of the data read, and when ops.datbuf == NULL, it serves to specify the full OOB read length. The patch inlined below is the slightly updated version of the previous patch serving the same purpose, but with the new Artem's comments taken into account. Artem, BTW, thanks a lot for your valuable input! Signed-off-by: Vitaly Wool Signed-off-by: David Woodhouse --- include/linux/mtd/mtd.h | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) (limited to 'include/linux/mtd/mtd.h') diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index 94a443d45258..4fc391ec9d01 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -75,15 +75,12 @@ typedef enum { * struct mtd_oob_ops - oob operation operands * @mode: operation mode * - * @len: number of bytes to write/read. When a data buffer is given - * (datbuf != NULL) this is the number of data bytes. When - * no data buffer is available this is the number of oob bytes. + * @len: number of data bytes to write/read * - * @retlen: number of bytes written/read. When a data buffer is given - * (datbuf != NULL) this is the number of data bytes. When - * no data buffer is available this is the number of oob bytes. + * @retlen: number of data bytes written/read * - * @ooblen: number of oob bytes per page + * @ooblen: number of oob bytes to write/read + * @oobretlen: number of oob bytes written/read * @ooboffs: offset of oob data in the oob area (only relevant when * mode = MTD_OOB_PLACE) * @datbuf: data buffer - if NULL only oob data are read/written @@ -94,6 +91,7 @@ struct mtd_oob_ops { size_t len; size_t retlen; size_t ooblen; + size_t oobretlen; uint32_t ooboffs; uint8_t *datbuf; uint8_t *oobbuf; -- cgit v1.3-8-gc7d7 From c0fe10aef354912c38c43991dd38c16f1828cfe3 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Mon, 13 Nov 2006 13:47:43 +0200 Subject: [MTD] increase MAX_MTD_DEVICES Signed-off-by: Artem Bityutskiy --- include/linux/mtd/mtd.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/mtd/mtd.h') diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index 4fc391ec9d01..e34bbc98d4fe 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -23,7 +23,7 @@ #define MTD_CHAR_MAJOR 90 #define MTD_BLOCK_MAJOR 31 -#define MAX_MTD_DEVICES 16 +#define MAX_MTD_DEVICES 32 #define MTD_ERASE_PENDING 0x01 #define MTD_ERASING 0x02 -- cgit v1.3-8-gc7d7 From 29072b96078ffde36f03d51e6b5d0cff1ba8c7df Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 28 Sep 2006 15:38:36 +0200 Subject: [MTD] NAND: add subpage write support Many SLC NANDs support up to 4 writes at one NAND page. Add support of this feature. Signed-off-by: Artem Bityutskiy --- drivers/mtd/mtdconcat.c | 1 + drivers/mtd/mtdpart.c | 1 + drivers/mtd/nand/nand_base.c | 53 ++++++++++++++++++++++++++++++++++++-------- include/linux/mtd/mtd.h | 2 ++ include/linux/mtd/nand.h | 9 ++++++++ 5 files changed, 57 insertions(+), 9 deletions(-) (limited to 'include/linux/mtd/mtd.h') diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c index ec51483b1c51..06902683bc2a 100644 --- a/drivers/mtd/mtdconcat.c +++ b/drivers/mtd/mtdconcat.c @@ -772,6 +772,7 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[], /* subdevices to c concat->mtd.ecc_stats.badblocks += subdev[i]->ecc_stats.badblocks; if (concat->mtd.writesize != subdev[i]->writesize || + concat->mtd.subpage_sft != subdev[i]->subpage_sft || concat->mtd.oobsize != subdev[i]->oobsize || concat->mtd.ecctype != subdev[i]->ecctype || concat->mtd.eccsize != subdev[i]->eccsize || diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c index 89692f898ef4..bafd2fba87bd 100644 --- a/drivers/mtd/mtdpart.c +++ b/drivers/mtd/mtdpart.c @@ -340,6 +340,7 @@ int add_mtd_partitions(struct mtd_info *master, slave->mtd.oobsize = master->oobsize; slave->mtd.ecctype = master->ecctype; slave->mtd.eccsize = master->eccsize; + slave->mtd.subpage_sft = master->subpage_sft; slave->mtd.name = parts[i].name; slave->mtd.bank_size = master->bank_size; diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 5dcb2e066ce7..eed3271b99cc 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -1590,7 +1590,7 @@ static uint8_t *nand_fill_oob(struct nand_chip *chip, uint8_t *oob, return NULL; } -#define NOTALIGNED(x) (x & (mtd->writesize-1)) != 0 +#define NOTALIGNED(x) (x & (chip->subpagesize - 1)) != 0 /** * nand_do_write_ops - [Internal] NAND write with ECC @@ -1603,15 +1603,16 @@ static uint8_t *nand_fill_oob(struct nand_chip *chip, uint8_t *oob, static int nand_do_write_ops(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops) { - int chipnr, realpage, page, blockmask; + int chipnr, realpage, page, blockmask, column; struct nand_chip *chip = mtd->priv; uint32_t writelen = ops->len; uint8_t *oob = ops->oobbuf; uint8_t *buf = ops->datbuf; - int bytes = mtd->writesize; - int ret; + int ret, subpage; ops->retlen = 0; + if (!writelen) + return 0; /* reject writes, which are not page aligned */ if (NOTALIGNED(to) || NOTALIGNED(ops->len)) { @@ -1620,8 +1621,11 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to, return -EINVAL; } - if (!writelen) - return 0; + column = to & (mtd->writesize - 1); + subpage = column || (writelen & (mtd->writesize - 1)); + + if (subpage && oob) + return -EINVAL; chipnr = (int)(to >> chip->chip_shift); chip->select_chip(mtd, chipnr); @@ -1644,12 +1648,24 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to, memset(chip->oob_poi, 0xff, mtd->oobsize); while(1) { + int bytes = mtd->writesize; int cached = writelen > bytes && page != blockmask; + uint8_t *wbuf = buf; + + /* Partial page write ? */ + if (unlikely(column || writelen < (mtd->writesize - 1))) { + cached = 0; + bytes = min_t(int, bytes - column, (int) writelen); + chip->pagebuf = -1; + memset(chip->buffers->databuf, 0xff, mtd->writesize); + memcpy(&chip->buffers->databuf[column], buf, bytes); + wbuf = chip->buffers->databuf; + } if (unlikely(oob)) oob = nand_fill_oob(chip, oob, ops); - ret = chip->write_page(mtd, chip, buf, page, cached, + ret = chip->write_page(mtd, chip, wbuf, page, cached, (ops->mode == MTD_OOB_RAW)); if (ret) break; @@ -1658,6 +1674,7 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to, if (!writelen) break; + column = 0; buf += bytes; realpage++; @@ -2201,8 +2218,8 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd, /* Newer devices have all the information in additional id bytes */ if (!type->pagesize) { int extid; - /* The 3rd id byte contains non relevant data ATM */ - extid = chip->read_byte(mtd); + /* The 3rd id byte holds MLC / multichip data */ + chip->cellinfo = chip->read_byte(mtd); /* The 4th id byte is the important one */ extid = chip->read_byte(mtd); /* Calc pagesize */ @@ -2482,6 +2499,24 @@ int nand_scan_tail(struct mtd_info *mtd) } chip->ecc.total = chip->ecc.steps * chip->ecc.bytes; + /* + * Allow subpage writes up to ecc.steps. Not possible for MLC + * FLASH. + */ + if (!(chip->options & NAND_NO_SUBPAGE_WRITE) && + !(chip->cellinfo & NAND_CI_CELLTYPE_MSK)) { + switch(chip->ecc.steps) { + case 2: + mtd->subpage_sft = 1; + break; + case 4: + case 8: + mtd->subpage_sft = 2; + break; + } + } + chip->subpagesize = mtd->writesize >> mtd->subpage_sft; + /* Initialize state */ chip->state = FL_READY; diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index e34bbc98d4fe..18acb6d0033b 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -200,6 +200,8 @@ struct mtd_info { /* ECC status information */ struct mtd_ecc_stats ecc_stats; + /* Subpage shift (NAND) */ + int subpage_sft; void *priv; diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index 6fc3e07497e0..1aeedf27a1ff 100644 --- a/include/linux/mtd/nand.h +++ b/include/linux/mtd/nand.h @@ -166,6 +166,9 @@ typedef enum { * for all large page devices, as they do not support * autoincrement.*/ #define NAND_NO_READRDY 0x00000100 +/* Chip does not allow subpage writes */ +#define NAND_NO_SUBPAGE_WRITE 0x00000200 + /* Options valid for Samsung large page devices */ #define NAND_SAMSUNG_LP_OPTIONS \ @@ -193,6 +196,9 @@ typedef enum { /* Nand scan has allocated controller struct */ #define NAND_CONTROLLER_ALLOC 0x80000000 +/* Cell info constants */ +#define NAND_CI_CHIPNR_MSK 0x03 +#define NAND_CI_CELLTYPE_MSK 0x0C /* * nand_state_t - chip states @@ -341,6 +347,7 @@ struct nand_buffers { * @chipsize: [INTERN] the size of one chip for multichip arrays * @pagemask: [INTERN] page number mask = number of (pages / chip) - 1 * @pagebuf: [INTERN] holds the pagenumber which is currently in data_buf + * @subpagesize: [INTERN] holds the subpagesize * @ecclayout: [REPLACEABLE] the default ecc placement scheme * @bbt: [INTERN] bad block table pointer * @bbt_td: [REPLACEABLE] bad block table descriptor for flash lookup @@ -388,6 +395,8 @@ struct nand_chip { unsigned long chipsize; int pagemask; int pagebuf; + int subpagesize; + uint8_t cellinfo; int badblockpos; nand_state_t state; -- cgit v1.3-8-gc7d7 From 7799308f34d3c3371a319559687c78c0f2506fcf Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Wed, 11 Oct 2006 14:52:44 +0300 Subject: [MTD] add get_mtd_device_nm() function This patch adds one more function to the MTD interface to make it possible to open MTD devices by their names, not only numbers. This is very handy in many situations. Also, MTD device number depend on load order and may vary, while names are fixed. Signed-off-by: Artem Bityutskiy --- drivers/mtd/mtdcore.c | 38 ++++++++++++++++++++++++++++++++++++++ include/linux/mtd/mtd.h | 1 + 2 files changed, 39 insertions(+) (limited to 'include/linux/mtd/mtd.h') diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index c4d26de74349..06ec9f836ae5 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -223,6 +224,42 @@ struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) return ret; } +/** + * get_mtd_device_nm - obtain a validated handle for an MTD device by + * device name + * @name: MTD device name to open + * + * This function returns MTD device description structure in case of + * success and an error code in case of failure. + */ + +struct mtd_info *get_mtd_device_nm(const char *name) +{ + int i; + struct mtd_info *mtd = ERR_PTR(-ENODEV); + + mutex_lock(&mtd_table_mutex); + + for (i = 0; i < MAX_MTD_DEVICES; i++) { + if (mtd_table[i] && !strcmp(name, mtd_table[i]->name)) { + mtd = mtd_table[i]; + break; + } + } + + if (i == MAX_MTD_DEVICES) + goto out_unlock; + + if (!try_module_get(mtd->owner)) + goto out_unlock; + + mtd->usecount++; + +out_unlock: + mutex_unlock(&mtd_table_mutex); + return mtd; +} + void put_mtd_device(struct mtd_info *mtd) { int c; @@ -267,6 +304,7 @@ int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs, EXPORT_SYMBOL(add_mtd_device); EXPORT_SYMBOL(del_mtd_device); EXPORT_SYMBOL(get_mtd_device); +EXPORT_SYMBOL(get_mtd_device_nm); EXPORT_SYMBOL(put_mtd_device); EXPORT_SYMBOL(register_mtd_user); EXPORT_SYMBOL(unregister_mtd_user); diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index 18acb6d0033b..89e937dfef55 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -216,6 +216,7 @@ extern int add_mtd_device(struct mtd_info *mtd); extern int del_mtd_device (struct mtd_info *mtd); extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num); +extern struct mtd_info *get_mtd_device_nm(const char *name); extern void put_mtd_device(struct mtd_info *mtd); -- cgit v1.3-8-gc7d7 From 9fe912cea32aec18f860c95e8574410b5892481b Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Wed, 11 Oct 2006 14:52:45 +0300 Subject: [MTD] add get and put methods This patch adds get_device() and put_device() methods to the MTD description structure (struct mtd_info). These methods are called by MTD whenever the MTD device is get or put. They are needed when the underlying driver is something smarter then just flash chip driver, for example UBI. Signed-off-by: Artem Bityutskiy --- drivers/mtd/mtdcore.c | 37 ++++++++++++++++++++++++++++++------- include/linux/mtd/mtd.h | 7 +++++++ 2 files changed, 37 insertions(+), 7 deletions(-) (limited to 'include/linux/mtd/mtd.h') diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 06ec9f836ae5..f11f55f02413 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -214,12 +214,23 @@ struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) ret = NULL; } - if (ret && !try_module_get(ret->owner)) + if (!ret) + goto out_unlock; + + if (!try_module_get(ret->owner)) { + ret = NULL; + goto out_unlock; + } + + if (ret->get_device && ret->get_device(ret)) { + module_put(ret->owner); ret = NULL; + goto out_unlock; + } - if (ret) - ret->usecount++; + ret->usecount++; +out_unlock: mutex_unlock(&mtd_table_mutex); return ret; } @@ -235,8 +246,8 @@ struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) struct mtd_info *get_mtd_device_nm(const char *name) { - int i; - struct mtd_info *mtd = ERR_PTR(-ENODEV); + int i, err = -ENODEV; + struct mtd_info *mtd = NULL; mutex_lock(&mtd_table_mutex); @@ -247,17 +258,27 @@ struct mtd_info *get_mtd_device_nm(const char *name) } } - if (i == MAX_MTD_DEVICES) + if (!mtd) goto out_unlock; if (!try_module_get(mtd->owner)) goto out_unlock; + if (mtd->get_device) { + err = mtd->get_device(mtd); + if (err) + goto out_put; + } + mtd->usecount++; + mutex_unlock(&mtd_table_mutex); + return mtd; +out_put: + module_put(mtd->owner); out_unlock: mutex_unlock(&mtd_table_mutex); - return mtd; + return ERR_PTR(err); } void put_mtd_device(struct mtd_info *mtd) @@ -266,6 +287,8 @@ void put_mtd_device(struct mtd_info *mtd) mutex_lock(&mtd_table_mutex); c = --mtd->usecount; + if (mtd->put_device) + mtd->put_device(mtd); mutex_unlock(&mtd_table_mutex); BUG_ON(c < 0); diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index 89e937dfef55..d644e57703ad 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -207,6 +207,13 @@ struct mtd_info { struct module *owner; int usecount; + + /* If the driver is something smart, like UBI, it may need to maintain + * its own reference counting. The below functions are only for driver. + * The driver may register its callbacks. These callbacks are not + * supposed to be called by MTD users */ + int (*get_device) (struct mtd_info *mtd); + void (*put_device) (struct mtd_info *mtd); }; -- cgit v1.3-8-gc7d7