linux-stable.git/drivers/mtd/mtdcore.c, branch linux-3.5.y Linux kernel stable tree mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN 2012-05-14T04:14:23+00:00 Mike Dunn mikedunn@newsguy.com 2012-04-25T19:06:11+00:00 edbc4540e02c201bdd4f4d498ebb6ed517fd36e2 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 <mikedunn@newsguy.com> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> Acked-by: Brian Norris <computersforpeace@gmail.com> Ivan Djelic <ivan.djelic@parrot.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
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 <mikedunn@newsguy.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Ivan Djelic <ivan.djelic@parrot.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: bitflip_threshold added to mtd_info and sysfs 2012-05-14T04:11:39+00:00 Mike Dunn mikedunn@newsguy.com 2012-04-25T19:06:08+00:00 d062d4ede877fcd2ecc4c6262abad09a6f32950a An element 'bitflip_threshold' is added to struct mtd_info, and also exposed as a read/write variable in sysfs. This will be used to determine whether or not mtd_read() returns -EUCLEAN or 0 (absent a hard error). If the driver leaves it as zero, mtd will set it to a default value of ecc_strength. This v2 adds the line that propagates bitflip_threshold from the master to the partitions - thanks Ivan¹. ¹ http://lists.infradead.org/pipermail/linux-mtd/2012-April/040900.html Signed-off-by: Mike Dunn <mikedunn@newsguy.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
An element 'bitflip_threshold' is added to struct mtd_info, and also exposed as
a read/write variable in sysfs.  This will be used to determine whether or not
mtd_read() returns -EUCLEAN or 0 (absent a hard error).  If the driver leaves it
as zero, mtd will set it to a default value of ecc_strength.

This v2 adds the line that propagates bitflip_threshold from the master to the
partitions - thanks Ivan¹.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-April/040900.html

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: expose ecc_strength through sysfs 2012-05-14T04:10:45+00:00 Mike Dunn mikedunn@newsguy.com 2012-04-25T19:06:07+00:00 a9b672e82bca47bf2b37ee869b8095000cf3ca88 ecc_strength element of struct mtd_info is exposed as a read-only variable in sysfs. Signed-off-by: Mike Dunn <mikedunn@newsguy.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
ecc_strength element of struct mtd_info is exposed as a read-only variable in
sysfs.

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: unify initialization of erase_info->fail_addr 2012-03-27T00:02:24+00:00 Shmulik Ladkani shmulik.ladkani@gmail.com 2012-02-09T13:36:29+00:00 3b27dac03972c10980ec5480ad8425fc95aae9ad Initialization of 'erase_info->fail_addr' to MTD_FAIL_ADDR_UNKNOWN prior erase operation is duplicated accross several MTD drivers, and also taken care of by some MTD users as well. Harmonize it: initialize 'fail_addr' within 'mtd_erase()' interface. Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
Initialization of 'erase_info->fail_addr' to MTD_FAIL_ADDR_UNKNOWN prior
erase operation is duplicated accross several MTD drivers, and also taken
care of by some MTD users as well.

Harmonize it: initialize 'fail_addr' within 'mtd_erase()' interface.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: check for zero length in OTP functions 2012-03-26T23:32:29+00:00 Artem Bityutskiy artem.bityutskiy@linux.intel.com 2012-02-08T14:37:14+00:00 de3cac9357b5aa9f9f02520e5f2567b06f3f75a7 This patch changes all the OTP functions like 'mtd_get_fact_prot_info()' and makes them return zero immediately if the input 'len' parameter is 0. This is not really needed currently, but most of the other functions do this, and it is just consistent to do the same in the OTP functions. This patch also moves the OTP functions from the header file to mtdcore.c because they become a bit too big for being inlined. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
This patch changes all the OTP functions like 'mtd_get_fact_prot_info()' and
makes them return zero immediately if the input 'len' parameter is 0. This is
not really needed currently, but most of the other functions do this, and it is
just consistent to do the same in the OTP functions.

This patch also moves the OTP functions from the header file to mtdcore.c
because they become a bit too big for being inlined.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: move zero length verification to MTD API functions 2012-03-26T23:32:19+00:00 Artem Bityutskiy artem.bityutskiy@linux.intel.com 2012-02-06T11:27:43+00:00 bcb1d238716d138c9e16347fc32b3c1ae006339e In many places in drivers we verify for the zero length, but this is very inconsistent across drivers. This is obviously the right thing to do, though. This patch moves the check to the MTD API functions instead and removes a lot of duplication. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
In many places in drivers we verify for the zero length, but this is very
inconsistent across drivers. This is obviously the right thing to do, though.
This patch moves the check to the MTD API functions instead and removes a lot
of duplication.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: harmonize mtd_point interface implementation 2012-03-26T23:32:11+00:00 Artem Bityutskiy artem.bityutskiy@linux.intel.com 2012-02-08T13:13:26+00:00 0dd5235f51fb0eb0b8cef3fed35be39b8a06d7bd Some MTD drivers return -EINVAL if the 'phys' parameter is not NULL, trying to convey that they cannot return the physical address. However, this is not very logical because they still can return the virtual address ('virt'). But some drivers (lpddr) just ignore the 'phys' parameter instead, which is a more logical thing to do. Let's harmonize this and: 1. Always initialize 'virt' and 'phys' to 'NULL' in 'mtd_point()'. 2. Do not return an error if the physical address cannot be found. So as a result, all drivers will set 'phys' to 'NULL' if it is not supported. None of the 'mtd_point()' users use 'phys' anyway, so this should not break anything. I guess we could also just delete this parameter later. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
Some MTD drivers return -EINVAL if the 'phys' parameter is not NULL, trying to
convey that they cannot return the physical address. However, this is not very
logical because they still can return the virtual address ('virt'). But some
drivers (lpddr) just ignore the 'phys' parameter instead, which is a more
logical thing to do.

Let's harmonize this and:

1. Always initialize 'virt' and 'phys' to 'NULL' in 'mtd_point()'.
2. Do not return an error if the physical address cannot be found.

So as a result, all drivers will set 'phys' to 'NULL' if it is not supported.
None of the 'mtd_point()' users use 'phys' anyway, so this should not break
anything. I guess we could also just delete this parameter later.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: remove retlen zeroing duplication 2012-03-26T23:29:34+00:00 Artem Bityutskiy artem.bityutskiy@linux.intel.com 2012-02-06T10:39:07+00:00 834247ec7e281dee839fe4a04bc1bbf0c7395172 The MTD API function now zero the 'retlen' parameter before calling the driver's method — do not do this again in drivers. This removes duplicated '*retlen = 0' assignent from the following methods: 'mtd_point()' 'mtd_read()' 'mtd_write()' 'mtd_writev()' 'mtd_panic_write()' Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
The MTD API function now zero the 'retlen' parameter before calling
the driver's method — do not do this again in drivers. This removes
duplicated '*retlen = 0' assignent from the following methods:

    'mtd_point()'
    'mtd_read()'
    'mtd_write()'
    'mtd_writev()'
    'mtd_panic_write()'

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: remove R/O checking duplication 2012-03-26T23:29:11+00:00 Artem Bityutskiy artem.bityutskiy@linux.intel.com 2012-02-03T16:13:23+00:00 664addc248d2fed68d013d26ff2fc796d7134259 Many drivers check whether the partition is R/O and return -EROFS if yes. Let's stop having duplicated checks and move them to the API functions instead. And again a bit of noise - deleted few too sparse newlines, sorry. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
Many drivers check whether the partition is R/O and return -EROFS if yes.
Let's stop having duplicated checks and move them to the API functions
instead.

And again a bit of noise - deleted few too sparse newlines, sorry.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
mtd: add offset and length checks to the API function 2012-03-26T23:28:05+00:00 Artem Bityutskiy artem.bityutskiy@linux.intel.com 2012-02-03T12:34:14+00:00 8273a0c911d8e068297ef70aa7241ee78db4c712 Add verification of the offset and length to MTD API functions and verify that MTD device offset and length are within MTD device size. The modified API functions are: 'mtd_erase()' 'mtd_point()' 'mtd_unpoint()' 'mtd_get_unmapped_area()' 'mtd_read()' 'mtd_write()' 'mtd_panic_write()' 'mtd_lock()' 'mtd_unlock()' 'mtd_is_locked()' 'mtd_block_isbad()' 'mtd_block_markbad()' This patch also uninlines these functions and exports in mtdcore.c because they are not performance-critical and do not have to be inlined. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> 
Add verification of the offset and length to MTD API functions and verify that
MTD device offset and length are within MTD device size.

The modified API functions are:

'mtd_erase()'
'mtd_point()'
'mtd_unpoint()'
'mtd_get_unmapped_area()'
'mtd_read()'
'mtd_write()'
'mtd_panic_write()'
'mtd_lock()'
'mtd_unlock()'
'mtd_is_locked()'
'mtd_block_isbad()'
'mtd_block_markbad()'

This patch also uninlines these functions and exports in mtdcore.c because they
are not performance-critical and do not have to be inlined.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>