linux-toradex.git/include/linux/mtd/nand.h, branch v3.6.10

mtd: nand: allow NAND_NO_SUBPAGE_WRITE to be set from driver

2012-10-21T16:32:42+00:00

commit bf7a01bf7987b63b121d572b240c132ec44129c4 upstream.

The NAND_CHIPOPTIONS_MSK has limited utility and is causing real bugs. It
silently masks off at least one flag that might be set by the driver
(NAND_NO_SUBPAGE_WRITE). This breaks the GPMI NAND driver and possibly
others.

Really, as long as driver writers exercise a small amount of care with
NAND_* options, this mask is not necessary at all; it was only here to
prevent certain options from accidentally being set by the driver. But the
original thought turns out to be a bad idea occasionally. Thus, kill it.

Note, this patch fixes some major gpmi-nand breakage.

Signed-off-by: Brian Norris 
Tested-by: Huang Shijie 
Cc: stable@vger.kernel.org
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse 
Signed-off-by: Greg Kroah-Hartman 


index a11253a..c429abd 100644

mtd: nand: remove 'sndcmd' parameter of 'read_oob/read_oob_raw'

2012-05-14T04:24:40+00:00

As of [mtd: nand: remove autoincrement 'sndcmd' code], the
NAND_CMD_READ0 command is issued unconditionally.

Thus, read_oob/read_oob_raw's 'sndcmd' argument is no longer needed, as
well as their return code.

Remove the 'sndcmd' parameter, and set the return code to 0.

Signed-off-by: Shmulik Ladkani 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: nand: add 'oob_required' argument to NAND {read,write}_page interfaces

2012-05-14T04:20:00+00:00

New NAND controllers can perform read/write via HW engines which don't expose
OOB data in their DMA mode. To reflect this, we should rework the nand_chip /
nand_ecc_ctrl interfaces that assume that drivers will always read/write OOB
data in the nand_chip.oob_poi buffer. A better interface includes a boolean
argument that explicitly tells the callee when OOB data is requested by the
calling layer (for reading/writing to/from nand_chip.oob_poi).

This patch adds the 'oob_required' parameter to each relevant {read,write}_page
interface; all 'oob_required' parameters are left unused for now. The next
patch will set the parameter properly in the nand_base.c callers, and follow-up
patches will make use of 'oob_required' in some of the callee functions.

Note that currently, there is no harm in ignoring the 'oob_required' parameter
and *always* utilizing nand_chip.oob_poi, but there can be
performance/complexity/design benefits from avoiding filling oob_poi in the
common case. I will try to implement this for some drivers which can be ported
easily.

Note: I couldn't compile-test all of these easily, as some had ARCH
dependencies.

[dwmw2: Merge later 1/0 vs. true/false cleanup]
Signed-off-by: Brian Norris 
Reviewed-by: Shmulik Ladkani 
Acked-by: Jiandong Zheng 
Acked-by: Mike Dunn 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: add read_byte support to plat_nand

2012-05-14T04:16:53+00:00

Lantiq SoCs have a External Bus Unit (EBU) that is used to attach MTD media.
As we need to co-exist with PCI on the same bus, certain swapping settings must
be applied. Similar to the NOR map driver we need to apply a fix to make NAND
work. The easiest way is to use byte reads.

Signed-off-by: John Crispin 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: nand: kill NAND_NO_AUTOINCR option

2012-05-14T04:15:38+00:00

No drivers use auto-increment NAND, so kill the NO_AUTOINCR option entirely.

Signed-off-by: Brian Norris 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN

2012-05-14T04:14:23+00:00

The drivers' _read() method, absent an error, returns a non-negative integer
indicating the maximum number of bit errors that were corrected in any one
region comprising an ecc step.  MTD returns -EUCLEAN if this is >=
bitflip_threshold, 0 otherwise.  If bitflip_threshold is zero, the comparison is
not made since these devices lack ECC and always return zero in the non-error
case (thanks Brian)¹.  Note that this is a subtle change to the driver
interface.

This and the preceding patches in this set were tested with ubi on top of the
nandsim and docg4 devices, running the ubi test io_basic from mtd-utils.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-March/040468.html

Signed-off-by: Mike Dunn 
Acked-by: Robert Jarzmik 
Acked-by: Brian Norris 
Ivan Djelic 
Signed-off-by: Artem Bityutskiy 

Signed-off-by: David Woodhouse

mtd: add ecc_strength fields to mtd structs

2012-03-26T23:56:36+00:00

This adds 'ecc_strength' to struct mtd_info.  This stores the maximum number of
bit errors that can be corrected in one writesize region.

For consistency with the nand code, 'strength' is similiarly added to struct
nand_ecc_ctrl.  This stores the maximum number of bit errors that can be
corrected in one ecc step.

Signed-off-by: Mike Dunn 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: nand: correct comment on nand_chip badblockbits

2012-03-26T23:12:42+00:00

The description for badblockbits is incorrect. I think someone just made
up a false description on the spot to satisfy some kerneldoc warning.

Signed-off-by: Brian Norris 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: nand: add Macronix manufacturer

2012-01-09T17:59:33+00:00

Macronix is produing SLC NAND MX30LF1208AA, so add their manufacturer
code to the manufacturer lists.

Signed-off-by: Brian Norris 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: David Woodhouse

mtd: nand: kill member `ops' of `struct nand_chip'

2011-09-11T12:57:44+00:00

The nand_chip.ops field is a struct that is passed around globally with
no particular reason. Every time it is used, it could just as easily be
replaced with a local struct that is updated on each operation. So make
it local.

Signed-off-by: Brian Norris 
Signed-off-by: Artem Bityutskiy