A significant amount of functions and other definitions are available
through the public mmc card.h header file. Let's slim down this public mmc
interface, as to prevent users from abusing it, by moving some of the
functions/definitions to private mmc header files.

This change concentrates on moving the functions into private mmc headers,
following changes may continue with additional clean-ups.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>

A significant amount of functions are available through the public mmc
core.h header file. Let's slim down this public mmc interface, as to
prevent users from abusing it, by moving some of the functions to private
mmc header files.

This change concentrates on moving the functions into private mmc headers,
following changes may continue with additional clean-ups, as an example
some functions can be turned into static.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>

This is the first step in cleaning up the private mmc header files. In this
change we makes sure each header file builds standalone, as that helps to
resolve dependencies.

While changing this, it also seems reasonable to stop including other
headers from inside a header itself which it don't depend upon.
Additionally, in some cases such dependencies are better resolved by
forward declaring the needed struct.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>

Per SDIO Simplified Specification V3, section 3.1.2, A host that
supports UHS-I sets S18R to 1 in the argument of CMD5 to request a
change of the signal voltage to 1.8V. If the card supports UHS-I and
the current signal voltage is 3.3V, S18A is set to 1 in the R4 response.
If the signal voltage is already 1.8V, the card sets S18A to 0 so that
host maintains the current signal voltage. UHS-I is supported in SD mode
and S18A is always 0 in SPI mode.

For the current code, if the signaling voltage is fixed 1.8v, so
the card will set S18A to 0 for rocr and thus we would clear the
R4_18V_PRESENT from ocr, which make core won't try to use uhs mode.

To fix it, we expect sdio_read_cccr would fail if the uhs mode won't
work at all. Note that it's interesting that some sdio cards still
response S18A even the voltage is fixed to 1.8v and the CMD11 will
also accepted and finish enabling UHS mode successfully. I guess this
is why folks didn't notice this problem. Anyway, fix it.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Add new helper function, mmc_sdio_resend_if_cond, to be
reused when trying to retry the init sequence.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

* A multiplication for the size determination of a memory allocation
  indicated that an array data structure should be processed.
  Thus use the corresponding function "kmalloc_array".

  This issue was detected by using the Coccinelle software.

* Replace the specification of a data structure by a pointer dereference
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

* The script "checkpatch.pl" pointed information out like the following.

  WARNING: Prefer kcalloc over kzalloc with multiply

  Thus fix the affected source code place.

* Replace the specification of a data structure by a pointer dereference
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Replace the specification of a data structure by a pointer dereference
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer according to the Linux coding style convention.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The script "checkpatch.pl" pointed information out like the following.

WARNING: quoted string split across lines

Thus fix affected source code places.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Use space characters at some source code places according to
the Linux coding style convention.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The script "checkpatch.pl" pointed information out like the following.

WARNING: Prefer seq_puts to seq_printf

Thus fix the affected source code place.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Add a missing character in the function description.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

* A multiplication for the size determination of a memory allocation
  indicated that an array data structure should be processed.
  Thus use the corresponding function "kmalloc_array".

  This issue was detected by using the Coccinelle software.

* Replace the specification of a data structure by a pointer dereference
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The caller may supply connection ID, index, or both. All combinations are
possible and mmc framework should not make any assumption on what exactly
caller wants.

Remove con_id override conditionals in mmc_gpiod_request_ro() and
mmc_gpiod_request_cd().
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

In the MMC subsystem, we see such initializers that only clears the
first member explicitly.

For example,

  struct mmc_request mrq = {NULL};

sets the first member (.sbc) to NULL explicitly.  However, this is
an unstable form because we may insert a non-pointer member at the
top of the struct mmc_request in the future. (if we do so, the
compiler will spit warnings.)

So, using a designated initializer is preferred coding style.  The
expression above is equivalent to:

  struct mmc_request mrq = { .sbc = NULL };

Of course, this does not express our intention.  We want to fill
all struct members with zeros.  Please note struct members are
implicitly zero-cleared unless otherwise specified in the initializer.

After all, the most reasonable (and stable) form is:

  struct mmc_request mrq = {};

Do likewise for mmc_command, mmc_data as well.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

With gcc-4.1.2:

    mmc/core/block.c: In function ‘mmc_blk_issue_discard_rq’:
    mmc/core/block.c:1150: warning: ‘arg’ may be used uninitialized in this function
    mmc/core/block.c:1150: warning: ‘nr’ may be used uninitialized in this function
    mmc/core/block.c:1150: warning: ‘from’ may be used uninitialized in this function

While this is a false positive, it can be avoided easily by jumping over
the checks for "err" that are always false.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

In the eMMC 5.0 version of the spec, several EXT_CSD fields about
device lifetime are added.

 - Two types of estimated indications reflected by averaged wear out of memory
 - An indication reflected by average reserved blocks

Export the information through sysfs.
Signed-off-by: NJungseung Lee <js07.lee@samsung.com>
Reviewed-by: NJaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Regressions for not being able to detect an eMMC HS DDR mode card has been
reported for the sdhci-esdhc-imx driver, but potentially other sdhci
variants may suffer from the similar problem.

The commit e173f891 ("mmc: core: Update CMD13 polling policy when
switch to HS DDR mode"), is causing the problem. It seems that change moved
one step to far, regarding changing the host's timing before polling for a
busy card.

To fix this, let's move back to the behaviour when the host's timing is
updated after the polling, but before the switch status is fetched and
validated.

In cases when polling with CMD13, we keep validating the switch status at
each attempt. However, to align with the other card busy detections
mechanism, let's fetch and validate the switch status also after the host's
timing is updated.
Reported-by: NClemens Gruber <clemens.gruber@pqgruber.com>
Reported-by: NGary Bisson <gary.bisson@boundarydevices.com>
Fixes: e173f891 ("mmc: core: Update CMD13 polling policy when switch..")
Cc: Shawn Lin <shawn.lin@rock-chips.com>
Cc: Dong Aisheng <aisheng.dong@nxp.com>
Cc: Haibo Chen <haibo.chen@nxp.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NClemens Gruber <clemens.gruber@pqgruber.com>
Tested-by: NJagan Teki <jagan@amarulasolutions.com>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Tested-by: NHaibo Chen <haibo.chen@nxp.com>
Reviewed-by: NDong Aisheng <aisheng.dong@nxp.com>

This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.
Requested-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The mmc_read_ssr() function results in DMA to the raw_ssr member of
struct mmc_card, which is not guaranteed to be cache line aligned & thus
might not meet the requirements set out in Documentation/DMA-API.txt:

  Warnings:  Memory coherency operates at a granularity called the cache
  line width.  In order for memory mapped by this API to operate
  correctly, the mapped region must begin exactly on a cache line
  boundary and end exactly on one (to prevent two separately mapped
  regions from sharing a single cache line).  Since the cache line size
  may not be known at compile time, the API will not enforce this
  requirement.  Therefore, it is recommended that driver writers who
  don't take special care to determine the cache line size at run time
  only map virtual regions that begin and end on page boundaries (which
  are guaranteed also to be cache line boundaries).

On some systems where DMA is non-coherent this can lead to us losing
data that shares cache lines with the raw_ssr array.

Fix this by kmalloc'ing a temporary buffer to perform DMA into. kmalloc
will ensure the buffer is suitably aligned, allowing the DMA to be
performed without any loss of data.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Fixes: 5275a652 ("mmc: sd: Export SD Status via “ssr” device attribute")
Cc: <stable@vger.kernel.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Commit e0097cf5 ("mmc: queue: Fix queue thread wake-up") did not go far
enough. mmc_wait_for_data_req_done() still contains some problems and can
be further simplified.  First it should not touch
context_info->is_waiting_last_req because that is a wake-up control used by
the owner of the context. Secondly, it should always return when one of its
wake-up conditions is met because, again, that is contolled by the owner of
the context.

While the current block driver does not have an issue, these problems were
exposed during testing of the Software Command Queue patches.

Fixes: e0097cf5 ("mmc: queue: Fix queue thread wake-up")
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Tested-by: NHarjani Ritesh <riteshh@codeaurora.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Once upon a time it made sense to keep the mmc block device driver and its
related code, in its own directory called card. Over time, more an more
functions/structures have become shared through generic mmc header files,
between the core and the card directory. In other words, the relationship
between them has become closer.

By sharing functions/structures via generic header files, it becomes easy
for outside users to abuse them. In a way to avoid that from happen, let's
move the files from card directory into the core directory, as it enables
us to move definitions of functions/structures into mmc core specific
header files.

Note, this is only the first step in providing a cleaner mmc interface for
outside users. Following changes will do the actual cleanup, as that is not
part of this change.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>

If a tuning command times out, the card could still be processing it, which
will cause problems for recovery. The eMMC specification says that CMD12
can be used to stop CMD21, so add a function that does that.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The JEDEC specification indicates CMD13 can be used after a HS200 switch
to check for errors. However in practice some boards experience CRC errors
in the CMD13 response. Consequently, for HS200, CRC errors are not a
reliable way to know the switch failed. If there really is a problem, we
would expect tuning will fail and the result ends up the same. So change
the error condition to ignore CRC errors in that case.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Acked-by: NJaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

BUG_ONs doesn't help anything except for stop the system from
running. If it occurs, it implies we should deploy proper error
handling for that. So this patch is gonna discard these meaningless
BUG_ONs and deploy error handling if needed.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

BUG_ONs doesn't help anything except for stop the system from
running. If it occurs, it implies we should deploy proper error
handling for that. So this patch is gonna discard these meaningless
BUG_ONs and deploy error handling if needed.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

BUG_ONs doesn't help anything except for stop the system from
running. If it occurs, it implies we should deploy proper error
handling for that. So this patch is gonna discard these meaningless
BUG_ONs and deploy error handling if needed.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Return error value for file_operations callback instead
of triggering BUG_ON which is meaningless. Personally I
don't believe n != EXT_CSD_STR_LEN could happen. Anyway,
propagate the error to the caller.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

BUG_ONs doesn't help anything except for stop the system from
running. If it occurs, it implies we should deploy proper error
handling for that. So this patch is gonna discard these meaningless
BUG_ONs and deploy error handling if needed.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Add definitions relating to Command Queuing.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The only time the driver sleeps expecting to be woken upon the arrival of
a new request, is when the dispatch queue is empty. The only time that it
is known whether the dispatch queue is empty is after NULL is returned
from blk_fetch_request() while under the queue lock.

Recognizing those facts, simplify the synchronization between the queue
thread and the request function. A couple of flags tell the request
function what to do, and the queue lock and barriers associated with
wake-ups ensure synchronization.

The result is simpler and allows the removal of the context_info lock.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NHarjani Ritesh <riteshh@codeaurora.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The void (*pre_req) callback in the struct mmc_host_ops vtable
is passing an argument "is_first_req" indicating whether this is
the first request or not.

None of the in-kernel users use this parameter: instead, since
they all just do variants of dma_map* they use the DMA cookie
to indicate whether a pre* callback has already been done for
a request when they decide how to handle it.

Delete the parameter from the callback and all users, as it is
just pointless cruft.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

According to the JEDEC specification, during bus timing change operations
for mmc, sending a CMD13 could trigger CRC errors.

As switching to HS DDR mode indeed causes a bus timing change, polling with
CMD13 to detect card busy, may thus potentially trigger CRC errors.
Currently these errors are treated as the switch to HS DDR mode failed.

To improve this behaviour, let's instead tell __mmc_switch() to retry when
it encounters CRC errors during polling.

Moreover, when switching to HS DDR mode, let's make sure the CMD13 polling
is done by having the mmc host and the mmc card, being configured to
operate at the same selected bus speed timing. Fix this by providing
MMC_TIMING_MMC_DDR52 as the timing parameter to __mmc_switch().
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>

In cases when the mmc host doesn't support HW busy detection, polling for a
card being busy by using CMD13 is beneficial. That is because, instead of
waiting a fixed amount of time, 500ms or the generic CMD6 time from
EXT_CSD, we find out a lot sooner when the card stops signaling busy. This
leads to a significant decreased total initialization time for the mmc
card.

However, to allow polling with CMD13 during a bus timing change operation,
such as switching to HS mode, we first need to update the mmc host's bus
timing before starting to poll. Deal with that, simply by providing
MMC_TIMING_MMC_HS as the timing parameter to __mmc_switch() from
mmc_select_hs().

By telling __mmc_switch() to allow polling with CMD13, also makes it
validate the CMD6 status, thus we can remove the corresponding checks.

When switching to HS400ES, the mmc_select_hs() function is called in one of
the intermediate steps. To still prevent CMD13 polling for HS400ES, let's
call the __mmc_switch() function in this path as it enables us to keep
using the existing method.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>

In cases when a speed mode change is requested for mmc cards, a CMD6 is
sent by calling __mmc_switch() during the card initialization. The CMD6
leads to the card entering a busy period. When that is completed, the host
must parse the CMD6 status to find out whether the change of the speed mode
succeeded.

To enable the mmc core to poll the card by using CMD13 to find out when the
busy period is completed, it's reasonable to make sure polling is done by
having the mmc host and the mmc card, being configured to operate at the
same selected bus speed timing.

Therefore, let's extend __mmc_switch() to take yet another parameter, which
allow its callers to update the bus speed timing of the mmc host. In this
way, __mmc_switch() also becomes capable of reading and validating the CMD6
status by sending a CMD13, in cases when that's desired.

If __mmc_switch() encounters a failure, we make sure to restores the old
bus speed timing for the mmc host, before propagating the error code.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>

According to the JEDEC specification, the SWITCH_ERROR bit in the device
status from a R1 response, is an error bit which may be cleared as soon as
the response that reports the error is sent.

When polling with CMD13 to find out when the card stops signaling busy
after a CMD6 has been sent, we currently parse only the last CMD13 response
for the SWITCH_ERROR bit. Consequentially we could loose important
information about the card.

In worst case if the card stops signaling busy within the allowed timeout,
we could end up believing that the CMD6 command completed successfully,
when in fact it didn't.

To improve the behaviour, let's parse each CMD13 response to see if the
SWITCH_ERROR bit is set in the device status. In such case, we abort the
polling loop and report the error.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>

The ignore_crc parameter/variable name is used at a couple of places in the
mmc core. Let's rename it to retry_crc_err to reflect its new purpose.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>

There are only one users left which calls __mmc_send_status(). Moreover,
the ignore_crc parameter isn't being used, so let's just remove these
redundant parts.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>

After a CMD6 command has been sent, the __mmc_switch() function might be
advised to poll the card for busy by using CMD13 and also by ignoring CRC
errors.

In the case of ignoring CRC errors, the mmc core tells the mmc host to also
ignore these errors via masking the MMC_RSP_CRC response flag. This seems
wrong, as it leads to that the mmc host could propagate an unreliable
response, instead of a proper error code.

What we really want, is not to ignore CRC errors but instead retry the
polling attempt. So, let's change this by treating a CRC error as the card
is still being busy and thus continue to run the polling loop.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>