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 v1.2.3 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 v1.2.3 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 --- include/linux/mtd/mtd.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/mtd/mtd.h') 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; -- cgit v1.2.3 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 --- include/linux/mtd/mtd.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/mtd/mtd.h') 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 v1.2.3 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 --- include/linux/mtd/mtd.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/linux/mtd/mtd.h') 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 v1.2.3