From 548cd3ab54da10f896daa7ca422236847a915734 Mon Sep 17 00:00:00 2001 From: "Bean Huo 霍斌斌 (beanhuo)" Date: Wed, 17 Dec 2014 07:35:45 +0000 Subject: mtd: spi-nor: Add quad I/O support for Micron SPI NOR This patch adds code which enables Quad I/O mode on Micron SPI NOR flashes. For Micron SPI NOR flash, enabling or disabling quad I/O protocol can be done By two methods, which are to use EVCR (Enhanced Volatile Configuration Register) and the ENTER QUAD I/O MODE command. There is no difference between these two methods. Unfortunately, for some Micron SPI NOR flashes, there no ENTER Quad I/O command (35h), such as n25q064. But for all current Micron SPI NOR, if it support quad I/O mode, using EVCR definitely be supported. It is a recommended method to enable Quad I/O mode by EVCR, Quad I/O protocol bit 7. When EVCR bit 7 is reset to 0, the SPI NOR flash will operate in quad I/O mode. This patch has been tested on N25Q512A and MT25TL256BAA1ESF. Micron SPI NOR of spi_nor_ids[] table all support this method. Signed-off-by: Bean Huo Acked-by: Marek Vasut Signed-off-by: Brian Norris --- include/linux/mtd/spi-nor.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include') diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index 63aeccf9ddc8..4720b86ee73d 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -56,6 +56,10 @@ /* Used for Spansion flashes only. */ #define SPINOR_OP_BRWR 0x17 /* Bank register write */ +/* Used for Micron flashes only. */ +#define SPINOR_OP_RD_EVCR 0x65 /* Read EVCR register */ +#define SPINOR_OP_WD_EVCR 0x61 /* Write EVCR register */ + /* Status Register bits. */ #define SR_WIP 1 /* Write in progress */ #define SR_WEL 2 /* Write enable latch */ @@ -67,6 +71,9 @@ #define SR_QUAD_EN_MX 0x40 /* Macronix Quad I/O */ +/* Enhanced Volatile Configuration Register bits */ +#define EVCR_QUAD_EN_MICRON 0x80 /* Micron Quad I/O */ + /* Flag Status Register bits */ #define FSR_READY 0x80 -- cgit v1.2.3 From 3efe41be224c4441f2a872a25471a14d85ceb7c6 Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Wed, 26 Nov 2014 01:01:08 -0800 Subject: mtd: implement common reboot notifier boilerplate cfi_cmdset_000{1,2}.c already implement their own reboot notifiers, and we're going to add one for NAND. Let's put the boilerplate in one place. Signed-off-by: Brian Norris Tested-by: Scott Branden --- drivers/mtd/mtdcore.c | 20 ++++++++++++++++++++ include/linux/mtd/mtd.h | 1 + 2 files changed, 21 insertions(+) (limited to 'include') diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 4c611871d7e6..cbc0fc46d2d6 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include @@ -365,6 +366,17 @@ static struct device_type mtd_devtype = { .release = mtd_release, }; +static int mtd_reboot_notifier(struct notifier_block *n, unsigned long state, + void *cmd) +{ + struct mtd_info *mtd; + + mtd = container_of(n, struct mtd_info, reboot_notifier); + mtd->_reboot(mtd); + + return NOTIFY_DONE; +} + /** * add_mtd_device - register an MTD device * @mtd: pointer to new MTD device info structure @@ -565,6 +577,11 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types, err = -ENODEV; } + if (mtd->_reboot) { + mtd->reboot_notifier.notifier_call = mtd_reboot_notifier; + register_reboot_notifier(&mtd->reboot_notifier); + } + return err; } EXPORT_SYMBOL_GPL(mtd_device_parse_register); @@ -579,6 +596,9 @@ int mtd_device_unregister(struct mtd_info *master) { int err; + if (master->_reboot) + unregister_reboot_notifier(&master->reboot_notifier); + err = del_mtd_partitions(master); if (err) return err; diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index 031ff3a9a0bd..c06f5373d870 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -227,6 +227,7 @@ struct mtd_info { int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs); int (*_suspend) (struct mtd_info *mtd); void (*_resume) (struct mtd_info *mtd); + void (*_reboot) (struct mtd_info *mtd); /* * If the driver is something smart, like UBI, it may need to maintain * its own reference counting. The below functions are only for driver. -- cgit v1.2.3