Commit Graph

83 Commits

Author SHA1 Message Date
Linus Walleij 1bee324a56 mmc: ops: export mmc_get_status()
This function retrieves the status of the card with the default
number of retries. Since the block layer wants to use this, and
since the block layer is a loadable kernel module, we need to
export this symbol.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-08-30 15:03:39 +02:00
Shawn Lin e5d0e17bb6 mmc: mmc_ops: fix a typo for comment of mmc_start_bkops
Just a trivial fix for that found by reading the code.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-08-30 14:01:28 +02:00
Ulf Hansson 0796e439c5 mmc: core: Clarify code for sending CSD
To make the code more consistent and to increase readability, add an
mmc_spi_send_csd() function, which gets called from mmc_send_csd() in case
of SPI mode.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-06-20 10:30:47 +02:00
Ulf Hansson c92e68d8a6 mmc: core: Drop mmc_all_send_cid() and use mmc_send_cxd_native() instead
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-06-20 10:30:46 +02:00
Ulf Hansson a147373250 mmc: core: Re-factor code for sending CID
Instead of having the caller to check for SPI mode, let's leave that to
internals of mmc_send_cid(). In this way the code gets cleaner and it
becomes clear what is specific to SPI and non-SPI mode.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-06-20 10:30:45 +02:00
Ulf Hansson 3df66e77e1 mmc: core: Remove redundant code in mmc_send_cid()
The mmc_send_cid() is never called using non SPI mode. Thus, let's remove
the redundant code dealing with this.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-06-20 10:30:45 +02:00
Ulf Hansson d9df173758 mmc: core: Move mmc_flush_cache() from core.c to mmc_ops.c
The mmc_flush_cache() is a eMMC specific function, let's move it to
mmc_ops.c to make that clear.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-06-20 10:30:44 +02:00
Ulf Hansson 0f2c05125e mmc: core: Move mmc_interrupt_hpi() from core.c to mmc_ops.c
The mmc_interrupt_hpi() is a eMMC specific function, let's move it to
mmc_ops.c to make that clear. The move also enables us to make
mmc_send_hpi_cmd() static, so let's do that change as well.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-06-20 10:30:43 +02:00
Ulf Hansson 1cf8f7e5af mmc: core: Move mmc bkops functions from core.c to mmc_ops.c
The mmc_start_bkops(), mmc_stop_bkops() and mmc_read_bkops_status()
functions are all specific to eMMCs. To make this clear, let's move them
from from core.c to mmc_ops.c and take the opportunity to make
mmc_read_bkops_status() static.

While moving them, get rid of MMC_BKOPS_MAX_TIMEOUT (4 min) and use the
common default timeout MMC_OPS_TIMEOUT_MS (10 min) instead, as there is no
need to have specific default timeout for bkops.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-06-20 10:30:43 +02:00
Ulf Hansson 2185bc2cd6 mmc: block: Use __mmc_send_status() and drop get_card_status()
The only reason to why the mmc block device driver needs to implements its
own version of how to get the status of the card, is that it needs to
specify a different amount of retries.

Therefore add a new exported function which allows the caller to specify
the number of retries and convert everybody to use it, as this simplifies
the code.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-20 10:30:27 +02:00
Winkler, Tomas 06c9ccb78e mmc: core: add proper be32 annotation
Annotate big endian values correctly and make sparse happy.
In mmc_app_send_scr remove scr function parameter as it was
updating card->raw_scr anyway.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-04-24 21:42:19 +02:00
Adrian Hunter b658af7184 mmc: mmc: Add functions to enable / disable the Command Queue
Add helper functions to enable or disable the Command Queue.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-04-24 21:42:02 +02:00
Masahiro Yamada c7836d1593 mmc: use empty initializer list to zero-clear structures
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: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-02-13 13:19:54 +01:00
Ulf Hansson ee6ff743e3 mmc: core: Restore parts of the polling policy when switch to HS/HS DDR
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 e173f8911f ("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: Clemens Gruber <clemens.gruber@pqgruber.com>
Reported-by: Gary Bisson <gary.bisson@boundarydevices.com>
Fixes: e173f8911f ("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: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Tested-by: Haibo Chen <haibo.chen@nxp.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
2017-01-16 16:17:42 +01:00
Adrian Hunter e711f03091 mmc: mmc: Introduce mmc_abort_tuning()
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: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:16:22 +01:00
Adrian Hunter ef3d232245 mmc: mmc: Relax checking for switch errors after HS200 switch
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: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:15:46 +01:00
Shawn Lin 8cce3ecc53 mmc: core: remove BUG_ONs from mmc
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: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 10:31:09 +01:00
Ulf Hansson aa33ce3c41 mmc: core: Enable __mmc_switch() to change bus speed timing for the host
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: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
2016-11-29 09:05:25 +01:00
Ulf Hansson 5ec32f8411 mmc: core: Check SWITCH_ERROR bit from each CMD13 response when polling
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: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
2016-11-29 09:05:24 +01:00
Ulf Hansson 625228fa3e mmc: core: Rename ignore_crc to retry_crc_err to reflect its purpose
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: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
2016-11-29 09:05:23 +01:00
Ulf Hansson 89e57aedda mmc: core: Remove redundant __mmc_send_status()
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: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
2016-11-29 09:05:23 +01:00
Ulf Hansson 437590a123 mmc: core: Retry instead of ignore at CRC errors when polling for busy
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: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
2016-11-29 09:05:22 +01:00
Ulf Hansson 70562644f4 mmc: core: Don't use ->card_busy() and CMD13 in combination when polling
When polling for busy after sending a MMC_SWITCH command, both the optional
->card_busy() callback and CMD13 are being used in conjunction.

This doesn't make sense. Instead it's more reasonable to rely solely on the
->card_busy() callback when it exists. Let's change that and instead use
the CMD13 as a fall-back. In this way we avoid sending CMD13, unless it's
really needed.

Within this context, let's also take the opportunity to make some
additional clean-ups and clarifications to the related code.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
2016-11-29 09:00:35 +01:00
Ulf Hansson 716bdb8953 mmc: core: Factor out code related to polling in __mmc_switch()
In yet another step of cleaning up __mmc_switch(), let's factor out the
code that deals with card busy polling.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
2016-11-29 09:00:34 +01:00
Ulf Hansson cb26ce069f mmc: core: Clarify code which deals with polling in __mmc_switch()
The __mmc_switch() deserves a clean-up. In this step, let's move some code
outside of the do-while loop, which deal deals with the card busy polling.

This change simplifies the code in that sense that it becomes easier to follow
what is being executed during card busy polling, but it also gives a better
understanding for when polling isn't done.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
2016-11-29 09:00:33 +01:00
Ulf Hansson 20348d1981 mmc: core: Make mmc_switch_status() available for mmc core
Following changes needs mmc_switch_status() to be available both from mmc.c
and mmc_ops.c. Allow that by moving its implementation to mmc_ops.c and
make it available via mmc_ops.h.

Moving mmc_switch_status() to mmc_ops.c, also enables us to turn
mmc_switch_status_error() into static function. So let's take the
opportunity to change this as well.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
2016-11-29 09:00:33 +01:00
Chaotian Jing 987aa5f805 mmc: mmc: fix switch timeout issue caused by jiffies precision
with CONFIG_HZ=100, the precision of jiffies is 10ms, and the
generic_cmd6_time of some card is also 10ms. then, may be current
time is only 5ms, but already timed out caused by jiffies precision.

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:09 +02:00
Chaotian Jing 87a18a6a56 mmc: mmc: Use ->card_busy() to detect busy cards in __mmc_switch()
Some MMC hosts do not support MMC_CAP_WAIT_WHILE_BUSY, but implements the
->card_busy() callback. In such cases, extend __mmc_switch() to use this
method to check card status after switch command.

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:08 +02:00
Masahiro Yamada 0899e74193 mmc: remove unnecessary assignment statements before return
Variable assignment just before return is redundant.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-02-29 11:02:47 +01:00
Chaotian Jing 3bbb0deea6 mmc: core: fix __mmc_switch timeout caused by preempt
there is a time window between __mmc_send_status() and time_afer(),
on some eMMC chip, the timeout_ms is only 10ms, if this thread was
scheduled out during this period, then, even card has already changes
to transfer state by the result of CMD13, this part of code also treat
it to timeout error.
So, need calculate timeout first, then call __mmc_send_status(), if
already timeout and card still in programing state, then treat it to
the real timeout error.

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-12-22 11:32:18 +01:00
Chaotian Jing 9979dbe515 mmc: mmc: extend the mmc_send_tuning()
The mmc_execute_tuning() has already prepared the opcode,
there is no need to prepare it again at mmc_send_tuning(),
and, there is a BUG of mmc_send_tuning() to determine the opcode
by bus width, assume eMMC was running at HS200, 4bit mode,
then the mmc_send_tuning() will overwrite the opcode from CMD21
to CMD19, then got error.

in addition, extend an argument of "cmd_error" to allow getting
if there was cmd error when tune response.

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
[Ulf: Rebased patch]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-27 10:38:41 +01:00
Ulf Hansson f90d2e4035 mmc: core: Convert __mmc_switch() into an internal core function
As there are no users of the __mmc_switch() API, except for the mmc core
itself, let's convert it from an exported function into an internal.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 15:59:54 +01:00
Adrian Hunter ed16f58dc0 mmc: core: Separate out the mmc_switch status check so it can be re-used
Make a separate function to do the mmc_switch status check
so it can be re-used. This is preparation for adding support
for HS400 re-tuning.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:56 +02:00
Adrian Hunter c6dbab9cb5 mmc: core: Hold re-tuning during switch commands
Hold re-tuning during switch commands to prevent
it from conflicting with the busy state or the CMD13
verification.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:54 +02:00
Ulf Hansson 04cdbbfa73 mmc: core: Make tuning block patterns static
Since previous patches removed the need for the tuning block patterns
to be exported, let's move them close to the mmc_send_tuning() API.

Those are now intended to be used only by the mmc core.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
2015-01-19 09:56:24 +01:00
Ulf Hansson fe5afb13d4 mmc: core: Let mmc_send_tuning() to take struct mmc_host* as parameter
To be able to use mmc_send_tuning() prior the struct mmc_card has been
allocated, let's convert it to take the struct mmc_host* as parameter
instead.

Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Dong Aisheng <b29396@freescale.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
2014-12-08 09:11:04 +01:00
Minda Chen 996903de92 mmc: core: add core-level function for sending tuning commands
According to the SD card spec, Add a manual tuning command function
for SDR104/HS200.
Sending command 19 or command 21 to read data and compare with the
tunning block pattern.

This patch will help to decrease some platform private codes in SDHCI
platform_execute_tuning() callbacks.

Signed-off-by: Minda Chen <Minda.Chen@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-11-26 14:36:51 +01:00
Ulf Hansson 22b787007f mmc: core: Convert to use kzalloc() for CXD register buffers
While allocating buffers for CXD data, let's use kzalloc() to make sure
those are zeroed.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-11-10 12:40:45 +01:00
Ulf Hansson 601ed60cef mmc: core: Don't handle buffers on stack while fetching CXD registers
Due to previous patches, all callers of mmc_send_cxd_data() now
allocates their buffers from the heap. This enables us to simplify
mmc_send_cxd_data() by removing the support of handling buffers, which
are allocated from the stack.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-11-10 12:40:45 +01:00
Ulf Hansson 2fc91e8b0e mmc: core: Remove the redundant mmc_send_ext_csd() API
Previous patches has replaced the calls to mmc_send_ext_csd() into
mmc_get_ext_csd(), thus mmc_send_ext_csd() has become redundant. Let's
remove it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-11-10 12:40:44 +01:00
Ulf Hansson e21aa519ee mmc: core: Export mmc_get_ext_csd()
Callers of mmc_send_ext_csd() will be able to decrease code duplication
by using mmc_get_ext_csd() instead. Let's make it available.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-11-10 12:40:43 +01:00
Ulf Hansson 148bcab28f mmc: core: Add helper function for EXT_CSD support
The helper function mmc_can_ext_csd() will return a positive value if
the card supports the EXT_CSD register. Start using it at relavant
places in the mmc core.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-11-10 12:40:41 +01:00
Joe Perches 6606110d89 mmc: Convert pr_warning to pr_warn
Use the much more common pr_warn instead of pr_warning.

Other miscellanea:

o Coalesce formats
o Realign arguments
o Remove extra spaces when coalescing formats

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-09-24 10:13:09 +02:00
Sascha Hauer 3d705d14fe mmc: implement Driver Stage Register handling
Some eMMC and SD cards implement a DSR register that allows to tune
raise/fall times and drive strength of the CMD and DATA outputs.
The values to use depend on the card in use and the host.
It might be needed to reduce the drive strength to prevent voltage peaks
above the host's specification.

Implement a 'dsr' devicetree property that allows to specify the value
to set the DSR to. For non-dt setups the new members of mmc_host can be
set by board code.

This patch was initially authored by Sascha Hauer. It contains
improvements authored by Markus Niebel and Uwe Kleine-König.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Markus Niebel <Markus.Niebel@tq-group.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2014-09-09 13:59:07 +02:00
Ulf Hansson b9ec26160f mmc: core: Fixup busy detection for mmc switch operations
If the host controller supports busy detection in HW, we expect the
MMC_CAP_WAIT_WHILE_BUSY to be set. Likewise the corresponding
host->max_busy_timeout should reflect the maximum busy detection
timeout supported by the host.

Previously we expected a host that supported MMC_CAP_WAIT_WHILE_BUSY to
cope with any timeout, which just isn't feasible due to HW limitations.

For most switch operations, R1B responses are expected and thus we need
to check for busy detection completion. To cope with cases where the
requested busy detection timeout is greater than what the host are able
to support, we fallback to use a R1 response instead. This will prevent
the host from doing HW busy detection.

In those cases, busy detection completion is handled by polling the for
the card's status using CMD13. This is the same mechanism used when the
host doesn't support MMC_CAP_WAIT_WHILE_BUSY.

Do note, a host->max_busy_timeout set to zero, is interpreted by the
mmc core as it don't know what the host supports. It will then provide
the host with whatever timeout the mmc core finds suitable.

For some cases the mmc core has unfurtunate no clue of what timeout to
use. In these cases we provide the host with a timeout value of zero,
which the host may interpret as use whatever timeout it finds suitable.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
2014-02-23 10:40:38 -05:00
Ulf Hansson 636bd13c12 mmc: core: Minor simplifications to __mmc_switch
Instead of using several references to card->host, let's use a local
variable. That means we can remove the BUG_ON verifications for the
same pointers.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
2014-02-23 10:40:34 -05:00
Ulf Hansson 4509f84775 mmc: core: Add ignore_crc flag to __mmc_switch
Instead of handle specific adaptations, releated to certain switch
operations, inside __mmc_switch, push this to be handled by the caller
instead.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
2014-02-23 10:40:30 -05:00
Ulf Hansson 1d4d77444b mmc: core: Rename cmd_timeout_ms to busy_timeout
To better reflect that the cmd_timeout_ms is directly related to the
busy detection timeout, let's rename it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
2014-02-23 10:40:26 -05:00
Ulf Hansson ecd3a7dad9 mmc: core: Silence compiler warning in __mmc_switch
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2013-11-08 14:31:58 -05:00
Ulf Hansson 878e200bbb mmc: core: Do not poll for busy with status cmd for all switch cmds
Some switch operations like poweroff notify, shall according to the
spec not be followed by any other new commands. For these cases and
when the host does'nt support MMC_CAP_WAIT_WHILE_BUSY, we must not
send status commands to poll for busy detection. Instead wait for
the stated timeout from the EXT_CSD before completing the request.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2013-10-30 20:26:24 -04:00