mtd: nand: fix Samsung SLC NAND identification regression
A combination of the following two commits caused a regression in 3.7-rc1 when identifying some Samsung NAND, so that some previously working NAND were no longer detected properly: commit e3b88bd6 mtd: nand: add generic READ ID length calculation functions commit e2d3a35e mtd: nand: detect Samsung K9GBG08U0A, K9GAG08U0F ID Particularly, a regression was seen on Samsung K9F2G08U0B, with the following full 8-byte READ ID string: ec da 10 95 44 00 ec da The basic problem is that Samsung manufactures both SLC and MLC NAND that use a non-standard decoding table for deriving information from their IDs. I have heuristically determined that all the chips that use the new table have ID strings which wrap around after the 6th byte. Unfortunately, I overlooked the fact that some older Samsung SLC (which use a different decoding table) have "5 byte ID strings" which also wrap around after the 6th byte. This patch re-introduces a distinction between these old and new Samsung NAND by checking that the 6th byte is non-zero, allowing both old and new Samsung NAND to be detected properly. Signed-off-by: NBrian Norris <computersforpeace@gmail.com> Tested-by: NBrian Norris <computersforpeace@gmail.com> Reported-by: NMarek Vasut <marex@denx.de> Tested-by: NMarek Vasut <marex@denx.de> Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Showing
想要评论请 注册 或 登录