ca2a88f56a
Pull MTD updates from David Woodhouse:
- Various cleanups especially in NAND tests
- Add support for NAND flash on BCMA bus
- DT support for sh_flctl and denali NAND drivers
- Kill obsolete/superceded drivers (fortunet, nomadik_nand)
- Fix JFFS2 locking bug in ENOMEM failure path
- New SPI flash chips, as usual
- Support writing in 'reliable mode' for DiskOnChip G4
- Debugfs support in nandsim
* tag 'for-linus-20121219' of git://git.infradead.org/linux-mtd: (96 commits)
mtd: nand: typo in nand_id_has_period() comments
mtd: nand/gpio: use io{read,write}*_rep accessors
mtd: block2mtd: throttle writes by calling balance_dirty_pages_ratelimited.
mtd: nand: gpmi: reset BCH earlier, too, to avoid NAND startup problems
mtd: nand/docg4: fix and improve read of factory bbt
mtd: nand/docg4: reserve bb marker area in ecclayout
mtd: nand/docg4: add support for writing in reliable mode
mtd: mxc_nand: reorder part_probes to let cmdline override other sources
mtd: mxc_nand: fix unbalanced clk_disable() in error path
mtd: nandsim: Introduce debugfs infrastructure
mtd: physmap_of: error checking to prevent a NULL pointer dereference
mtg: docg3: potential divide by zero in doc_write_oob()
mtd: bcm47xxnflash: writing support
mtd: tests/read: initialize buffer for whole next page
mtd: at91: atmel_nand: return bit flips for the PMECC read_page()
mtd: fix recovery after failed write-buffer operation in cfi_cmdset_0002.c
mtd: nand: onfi need to be probed in 8 bits mode
mtd: nand: add NAND_BUSWIDTH_AUTO to autodetect bus width
mtd: nand: print flash size during detection
mted: nand_wait_ready timeout fix
...
Broadcom introduced new bus as replacement for older SSB. It is based on AMBA, however from programming point of view there is nothing AMBA specific we use. Standard AMBA drivers are platform specific, have hardcoded addresses and use AMBA standard fields like CID and PID. In case of Broadcom's cards every device consists of: 1) Broadcom specific AMBA device. It is put on AMBA bus, but can not be treated as standard AMBA device. Reading it's CID or PID can cause machine lockup. 2) AMBA standard devices called ports or wrappers. They have CIDs (AMBA_CID) and PIDs (0x103BB369), but we do not use that info for anything. One of that devices is used for managing Broadcom specific core. Addresses of AMBA devices are not hardcoded in driver and have to be read from EPROM. In this situation we decided to introduce separated bus. It can contain up to 16 devices identified by Broadcom specific fields: manufacturer, id, revision and class.