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History log of /drivers/mmc/core/sd.c
Revision Date Author Comments
12e626dd0ef04c2e43a193b623a914745e1fd1e9 04-Dec-2008 San Mehat <san@android.com> mmc: sd: Add retries in re-detection

Signed-off-by: San Mehat <san@android.com>

mmc: sd: Remove debugging printk

Signed-off-by: Dima Zavin <dima@android.com>
65a213ff7fcec3c901d1aa929008d98ed35ed866 01-Dec-2008 San Mehat <san@android.com> mmc: sd: When resuming, try a little harder to init the card

Signed-off-by: San Mehat <san@android.com>
9faee2387ae0ba36f1db00b55337990bbc89ca3e 11-Nov-2008 San Mehat <san@google.com> mmc: sd: Add new CONFIG_MMC_PARANOID_SD_INIT for enabling retries during SD detection

Signed-off-by: San Mehat <san@google.com>
6606110d89aefcb21b9e70adfe064987cbd8393a 12-Sep-2014 Joe Perches <joe@perches.com> 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>
3d705d14fe4c72be83bae1610680e209ee226b9d 19-Aug-2014 Sascha Hauer <s.hauer@pengutronix.de> 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>
cdc991790c51c693d0c347a5286af017826a5d01 23-Apr-2014 Seungwon Jeon <tgih.jun@samsung.com> mmc: drop the speed mode of card's state

Timing mode identifier has same role and can take the place
of speed mode. This change removes all related speed mode.

Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
d1e58212caa4fdd95dfb003ba6e90aa0c9c1ac03 08-Mar-2014 Axel Lin <axel.lin@ingics.com> mmc: Convert to use ATTRIBUTE_GROUPS

Use new ATTRIBUTE_GROUPS macro to declare attribute groups.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
2501c9179dff2add6aadd3898cd729e94e777d3a 30-Oct-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Use MMC_UNSAFE_RESUME as default behavior

Invoking system suspend or shutdown without using the Kconfig option
MMC_UNSAFE_RESUME, did trigger an ungraceful power cut of the card.

To improve the situation, change the behavior to always make use of the
available bus_ops callbacks that handles system suspend and shutdown
properly.

By changing the behavior MMC_UNSAFE_RESUME becomes redundant, so lets's
remove it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
9288cac05405a7da406097a44721aa4004609b4d 26-Nov-2013 Wolfram Sang <wsa@the-dreams.de> mmc: core: sd: implement proper support for sd3.0 au sizes

This reverts and updates commit 77776fd0a4cc541b9 ("mmc: sd: fix the
maximum au_size for SD3.0"). The au_size for SD3.0 cannot be achieved
by a simple bit shift, so this needs to be implemented differently.
Also, don't print the warning in case of 0 since 'not defined' is
different from 'invalid'.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: stable <stable@vger.kernel.org> # [3.12, 3.13]
Signed-off-by: Chris Ball <chris@printf.net>
4d22378221bd0ed69c2e99408d31c108d72aeb80 10-Oct-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Add MMC_CAP_RUNTIME_RESUME to resume at runtime_resume

In some environments it is to prefer to postpone the resume of the card
device until runtime_resume is being carried out, since it will mean a
signficant decrease of the total system resume time.

The reason of the decreased resume time is simply because of the actual
re-initalization of the card, which typically takes hundreds of
milliseconds, is performed outside the resume sequence and wont thus
affect it.

For removable card, the detect work tries to re-detect the card to make
sure it is still present, as a part of that sequence the card will also
be runtime_resumed and thus also fully resumed.

For a non-removable card, typically a mmc blk request will trigger a
runtime_resume and thus fully resume the card. This also means the
first request will likely suffer from an inital latency since the
re-initialization of the card needs to be performed.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
0cb403a227774f60f6f52137ca3618805498c4e6 10-Oct-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Improve runtime PM support during suspend/resume for sd/mmc

The card device is considered as in-active after it has been suspended.
To prevent any further runtime PM requests in suspend state, we then
disable runtime PM.

After the card device has been resumed, we shall consider it as active,
like we also do after a probe sequence. When resumed, we can safely
enable runtime PM again.

This will make sure the PM core can request the card device to go to
in-active state after a resume has been completed. Previously we had to
wait for new pm_runtime_get->pm_runtime_put cycle to be executed.

Additionally, once a resume has been carried out, update the last busy
mark. At the moment this will have no effect but if the PM core will
respect autosuspend enabled devices, when it directly triggers a
runtime_suspend from a runtime_idle, it will mean the card device will
be scheduled for a delayed runtime_suspend instead of done immediately.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
0cc81a8c6442e43618ff245948bfaa14fdf7938b 03-Oct-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Remove redundant mmc_power_up|off at runtime callbacks

Commit "mmc: core: Push common suspend|resume code into each bus_ops"
moved the responsibility for doing mmc_power_up|off into each
suspend/resume bus_ops. When using MMC_CAP_AGGRESSIVE_PM, through the
runtime callbacks, calls to mmc_power_up|off became redundant.

When removing them, we are also able to remove the calls to
mmc_claim|release_host, thus simplifing code a bit more.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
9ec775f7efd6d17084b4f361804d2030d50fca0e 02-Oct-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: Don't force card to active state when entering suspend/shutdown

By adding a card state that records if it is suspended or resumed, we
can accept asyncronus suspend/resume requests for the mmc and sd
bus_ops.

MMC_CAP_AGGRESSIVE_PM, will at request inactivity through the runtime
bus_ops callbacks, execute a suspend of the the card. In the state were
this has been done, we can receive a suspend request for the mmc bus,
which for sd and mmc forced the card to active state by a
pm_runtime_get_sync. In other words, the card was resumed and then
immediately suspended again, completely unnecessary.

Since the suspend/resume bus_ops callbacks for sd and mmc are now
capable of handling asynchronous requests, we no longer need to force
the card to active state before executing suspend. Evidently preventing
the above sequence for MMC_CAP_AGGRESSIVE_PM.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
726d6f2374410d980341bfeb49399614e689e702 16-Sep-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Collect common code for card ocr validation

Since mmc_select_voltage now only gets called from the attach sequence,
it makes sense to move the out of spec validations of the card ocr into
this function.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
ce69d37b7d8fa692c45d71d94aa0c921859b82ce 16-Sep-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Prevent violation of specs while initializing cards

According to eMMC/SD/SDIO specs, the VDD (VCC) voltage level must be
maintained during the initialization sequence. If we want/need to tune
the voltage level, a complete power cycle of the card must be executed.

Most host drivers conforms to the specifications by only allowing to
change VDD voltage level at the MMC_POWER_UP state, but some also cares
about MMC_POWER_ON state, which they should'nt. This patch will not
break those drivers, but they could clean up code to better reflect
what is expected from the protocol layer.

A big re-work of the mmc_select_voltage function is done to only change
VDD voltage level if the host supports MMC_CAP2_FULL_PWR_CYCLE.
Otherwise only validation of the host and card ocr mask will be done.

A very nice side-effect of this patch is that we now don't need to
reset the negotiated ocr mask at the mmc_power_off function, since now
it will actually reflect the present voltage level, which safely can be
used at the next power up and re-initialization. Moreover, we then only
need to execute mmc_select_voltage from the attach sequence.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
6904115095ad60ced638eb1e36e0e4e5e7de00b0 13-Sep-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Move cached value of the negotiated ocr mask to card struct

The negotiated ocr mask is directly related to the card. Once a card
gets removed, the mask shall be dropped. By moving the cache of the ocr
mask from the host struct to the card struct we have accomplished this.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
0f791fdad82a02af013e4fc8c385dc690080c366 12-Sep-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Let mmc_set_signal_voltage take ocr as parameter

This is yet another step of restructure code to be able to fixup the
setup of the negotiated ocr mask.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
4a065193c46a16f1ddf20622c7011c8f327e0478 12-Sep-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Let mmc_power_up|cycle take ocr as parameter

As a step to fixup the setup of the negotiated ocr mask, we need the
mmc_power_up|cycle functions to take the ocr as a parameter.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
77776fd0a4cc541b9a528eacc1d31ca47eb1ae7a 18-Jul-2013 Jaehoon Chung <jh80.chung@samsung.com> mmc: sd: fix the maximum au_size for SD3.0

Since SD Physical Layer specification V3.0, AU_SIZE is supported up
to 0xf. So If SD-card is supported v3.0, then max_au should be 0xf.

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
7fca96758e977497c67a424006c60aaf2d3db212 17-Jul-2013 Wei WANG <wei_wang@realsil.com.cn> mmc: core: free mmc_card if cmd 3,9,7 fails in mmc_sd_init_card

In function mmc_sd_init_card, if command 3/9/7 got failed, mmc_card
allocated just before won't be freed. This would cause memory leak.

Signed-off-by: Wei WANG <wei_wang@realsil.com.cn>
Signed-off-by: Chris Ball <cjb@laptop.org>
5992e78697484d8f58b749f87a06f89f4ba40a47 10-Jun-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Add shutdown callback for SD bus_ops

For the SD .shutdown callback we re-use the SD suspend function since
it performs the relevant actions.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
74590263384e5d4601de7f0ee2790477578829ea 10-Jun-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Push common suspend|resume code into each bus_ops

By moving code from the mmc_suspend|resume_host down into each
.suspend|resume bus_ops callback, we get a more flexible solution.

Some nice side effects are that we get a better understanding of each
bus_ops suspend|resume sequence and the common code don't have to take
care of specific corner cases, especially for the SDIO case.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
c4d770d72492df510077b277f21ac5f0dad9e5eb 02-May-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: core: Support aggressive power management for (e)MMC/SD

Aggressive power management is suitable when saving power is
essential. At request inactivity timeout, aka pm runtime
autosuspend timeout, the card will be suspended.

Once a new request arrives, the card will be re-initalized and
thus the first request will suffer from a latency. This latency
is card-specific, experiments has shown in general that SD-cards
has quite poor initialization time, around 300ms-1100ms. eMMC is
not surprisingly far better but still a couple of hundreds of ms
has been observed.

Except for the request latency, it is important to know that
suspending the card will also prevent the card from executing
internal house-keeping operations in idle mode. This could mean
degradation in performance.

To use this feature make sure the request inactivity timeout is
chosen carefully. This has not been done as a part of this patch.

Enable this feature by using host cap MMC_CAP_AGGRESSIVE_PM and
by setting CONFIG_MMC_UNSAFE_RESUME.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
e94cfef698aae6b209d8918dd319312e4b02118d 02-May-2013 Ulf Hansson <ulf.hansson@linaro.org> mmc: block: Enable runtime pm for mmc blkdevice

Once the mmc blkdevice is being probed, runtime pm will be enabled.
By using runtime autosuspend, the power save operations can be done
when request inactivity occurs for a certain time. Right now the
selected timeout value is set to 3 s. Obviously this value will likely
need to be configurable somehow since it needs to be trimmed depending
on the power save algorithm.

For SD-combo cards, we are still leaving the enablement of runtime PM
to the SDIO init sequence since it depends on the capabilities of the
SDIO func driver.

Moreover, when the blk device is being suspended, we make sure the device
will be runtime resumed. The reason for doing this is that we want the
host suspend sequence to be unaware of any runtime power save operations
done for the card in this phase. Thus it can just handle the suspend as
the card is fully powered from a runtime perspective.

Finally, this patch prepares to make it possible to move BKOPS handling
into the runtime callbacks for the mmc bus_ops. Thus IDLE BKOPS can be
accomplished.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
810e08ee425f8d7327e4b30069a9b2b3dccfc67d 17-Apr-2013 Fredrik Soderstedt <fredrik.soderstedt@stericsson.com> mmc: core: Only execute tuning for SDR50 and SDR104

Only execute tuning for sd and sdio devices that are using
SDR50 or SDR104.

Make sure clock is hold during tuning for sdio devices.

Signed-off-by: Fredrik Soderstedt <fredrik.soderstedt@stericsson.com>
Acked-by: Johan Rudholm <jrudholm@gmail.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
52983382c74f59a3953e622d7661a24e1bc4388a 31-Jan-2013 Kevin Liu <kliu5@marvell.com> mmc: sdhci: enhance preset value function

4d55c5a1 ("mmc: sdhci: enable preset value after uhs initialization")
added preset value support and enabled it by default during sd card init.

Below are the enhancements introduced by this patch:

1. In current code, preset value is enabled after setting clock finished,
which means the clock is manually set by driver firstly and then suddenly
switched to preset value at this point. So the first setting is useless
and unnecessary. What's more, the first clock setting may differ from the
preset one. The better way is enable preset value just after switch to
UHS mode so the preset value can take effect immediately. So move preset
value enable from mmc_sd_init_card to sdhci_set_ios which will be called
during set timing.

2. In current code, preset value is disabled at the beginning of
mmc_attach_sd. It's too late since low freq (400khz) should be set in
mmc_power_up. So move preset value disable to sdhci_set_ios which will
be called during power up.

3. host->clock and ios->drv_type should also be updated according to the
preset value if it's enabled. Current code missed this.

4. This patch also introduce a quirk to disable preset value in case
preset value doesn't work.

This patch has been verified on sdhci-pxav3 platform with both preset
enabled and disabled.

Signed-off-by: Kevin Liu <kliu5@marvell.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
0797e5f1453b2bedc08bbcbea0ea4fbe20350823 28-Jan-2013 Johan Rudholm <johan.rudholm@stericsson.com> mmc: core: Fixup signal voltage switch

When switching SD and SDIO cards from 3.3V to 1.8V signal levels, the
clock should be gated for 5 ms during the step. After enabling the
clock, the host should wait for at least 1 ms before checking for
failure. Failure by the card to switch is indicated by dat[0:3] being
pulled low. The host should check for this condition and power-cycle
the card if failure is indicated.

Add a retry mechanism for the SDIO case.

If the voltage switch fails repeatedly, give up and continue the
initialization using the original voltage.

This patch places a couple of requirements on the host driver:

1) mmc_set_ios with ios.clock = 0 must gate the clock
2) mmc_power_off must actually cut the power to the card
3) The card_busy host_ops member must be implemented

if these requirements are not fulfilled, the 1.8V signal voltage switch
will still be attempted but may not be successful.

Signed-off-by: Johan Rudholm <johan.rudholm@stericsson.com>
Signed-off-by: Kevin Liu <kliu5@marvell.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Wei WANG <wei_wang@realsil.com.cn>
Signed-off-by: Chris Ball <cjb@laptop.org>
567c89032cfdda8047562abe450947ac01f2d3c7 28-Jan-2013 Johan Rudholm <johan.rudholm@stericsson.com> mmc: core: Break out start_signal_voltage_switch

Allow callers to access the start_signal_voltage_switch host_ops
member without going through any cmd11 logic. This is mostly a
preparation for the following signal voltage switch patch.

Also, reset ios.signal_voltage to its original value if
start_signal_voltage_switch fails.

Signed-off-by: Johan Rudholm <johan.rudholm@stericsson.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Wei WANG <wei_wang@realsil.com.cn>
Signed-off-by: Chris Ball <cjb@laptop.org>
3f8a7fabd60e83eb2fb7add00d353d455c0e7a78 28-Jan-2013 Johan Rudholm <johan.rudholm@stericsson.com> mmc: sd: Simplify by using mmc_host_uhs

Signed-off-by: Johan Rudholm <johan.rudholm@stericsson.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
108ecc4cf9c46a4caabaf18efc42d19818c95b70 10-Jul-2012 Aaron Lu <aaron.lu@amd.com> mmc: core: reset signal voltage on power up

Add a call to mmc_set_signal_voltage() to set signal voltage to 3.3v in
mmc_power_up so that we do not need to touch signal voltage setting in
mmc/sd/sdio init functions and rescan function.

For mmc/sd cards, when doing a suspend/resume cycle, consider the unsafe
resume case, the card will lose its power and when powered on again, we
will set signal voltage to 3.3v in mmc_power_up before its resume function
gets called, which will re-init the card.

And for sdio cards, when doing a suspend/resume cycle, consider the unsafe
resume case, the card will either lose its power or not depending on if it
wants to wakeup the host. If power is not maintained, it is the same case as
mmc/sd cards. If power is maintained, mmc_power_up will not be called and
the card's signal voltage will remain at the last setting.

Signed-off-by: Aaron Lu <aaron.lu@amd.com>
Tested-by: Venkatraman S <svenkatr@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
55c4665ea0a42fd6427826bfce96eb4b0389262a 04-Jul-2012 Aaron Lu <aaron.lu@amd.com> mmc: sd: Fix sd current limit setting

Host has different current capabilities at different voltages, we need
to record these settings seperately. The defined voltages are 1.8/3.0/3.3.
For other voltages, we do not touch current limit setting.

Before we set the current limit for the sd card, find out the host's
operating voltage first and then find out the current capabilities of
the host at that voltage to set the current limit.

Signed-off-by: Aaron Lu <aaron.lu@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
a39ca6ae0a08994a59d017a445939e164bc77fd5 03-Jul-2012 Aaron Lu <aaron.lu@amd.com> mmc: core: Simplify and fix for SD switch processing

In mmc_read_switch, just do a one time mode 0 switch command to get the
support bits information, no need to do multiple times as the support
bits do not change with different arguments.

And no need to check current limit support bits, as these bits are
fixed according to the signal voltage. If the signal voltage is 1.8V,
the support bits would be 0xf and if the signal voltage is 3.3V, the
support bits would be 0x01. We will check host's ability to set the
current limit.

Signed-off-by: Aaron Lu <aaron.lu@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
b63b5e819d5b21ae493c17c356018ffa98d3ee1c 02-Jul-2012 Alan Cox <alan@linux.intel.com> mmc: core: correct invalid error checking

The effect of the existing code is that we continue blindly when we
should warn about an invalid allocation unit.

Reported-by: dcb314@hotmail.com
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=44061
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
0aa6770000bafa65c17cf44b6619d328d4fc79b3 28-May-2012 Philip Rakity <prakity@marvell.com> mmc: sdhci: only set 200mA support for 1.8v if 200mA is available

max_current_caps can return 0 if not available from the sd controller.
If no regulator is present or the regulator specifies a current
less then 200ma, we no longer still set the 200mA caps bit anyway.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Reviewed-by: Aaron Lu <aaron_lu@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
85e727edb963459d13cdd9ce84c335d251a005a7 31-May-2012 Jaehoon Chung <jh80.chung@samsung.com> mmc: core: return an error on suspend if mmc_deselect_cards fails

When mmc_host is not spi mode, mmc/sd is doing mmc_deselect_cards().
mmc_deselect_cards could be returned error.
If returned error, we can know something wrong when enter suspend.

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
e7747475b61fdc2a4a412475a9d64d8c309916e3 01-Mar-2012 Ulf Hansson <ulf.hansson@stericsson.com> mmc: core: Fixup suspend/resume issues for UHS-I cards

Even if cards supports 1.8V I/O voltage those should anyway be
initialized at 3.3V I/O according to (e)MMC, SD and SDIO specs.
Some eMMC and embedded SDIO devices are able to be initialized
at 1.8V as well, but it is better to be safe.

Do note that initialization in this context means that the card
has been completely powered off, otherwise the card will remain
at the last I/O voltage level that were negotitiated.

Due to the above being taken care of the suspend/resume issues
for UHS-I SD-cards has been fixed.

Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com>
Acked-by: Philip Rakity <prakity@marvell.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2c4967f741e87cdd63de7271b97807041dccbf3b 04-Feb-2012 Sujit Reddy Thumma <sthumma@codeaurora.org> mmc: core: Ensure clocks are always enabled before host interaction

Ensure clocks are always enabled before any interaction with the
host controller driver. This makes sure that there is no race
between host execution and the core layer turning off clocks
in different context with clock gating framework.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Per Forlin <per.forlin@stericsson.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
a4924c71aa43d4f8a3f342b1f71788349472e684 11-Jan-2012 Girish K S <girish.shivananjappa@linaro.org> mmc: core: HS200 mode support for eMMC 4.5

This patch adds the support of the HS200 bus speed for eMMC 4.5 devices.
The eMMC 4.5 devices have support for 200MHz bus speed. The function
prototype of the tuning function is modified to handle the tuning
command number which is different in sd and mmc case.

Signed-off-by: Girish K S <girish.shivananjappa@linaro.org>
Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
d30495048892980e5d453328d1cc9343b3f7e917 28-Nov-2011 Adrian Hunter <adrian.hunter@intel.com> mmc: allow upper layers to know immediately if card has been removed

Add a function mmc_detect_card_removed() which upper layers can use to
determine immediately if a card has been removed. This function should
be called after an I/O request fails so that all queued I/O requests
can be errored out immediately instead of waiting for the card device
to be removed.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
a303c5319c8e6ab0e744ebca118da8420043b2c3 15-Nov-2011 Philip Rakity <prakity@marvell.com> mmc: sdio: support SDIO UHS cards

This patch adds support for sdio UHS cards per the version 3.0
spec.

UHS mode is only enabled for version 3.0 cards when both the
host and the controller support UHS modes.

1.8v signaling support is removed if both the card and the
host do not support UHS. This is done to maintain
compatibility and some system/card combinations break when
1.8v signaling is enabled when the host does not support UHS.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Aaron Lu <Aaron.lu@amd.com>
Reviewed-by: Arindam Nath <arindam.nath@amd.com>
Tested-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
fffe5d5aa05b4e69f79bc75a51c5ee0fc6203fa5 08-Nov-2011 Qiang Liu <qiang.liu@freescale.com> mmc: sd: Macro name cleanup for high speed dtr

Add new macros for the high speed 50MHz case, rather than having
a confusing reuse of the value for UHS SDR50, which is 100MHz.

Reported-by: Aaron Lu <aaron.lu@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
0205a904df57bf2ed79571fe097b99d2940659b1 15-Jul-2011 Paul Gortmaker <paul.gortmaker@windriver.com> mmc: Fix implicit use of stat.h header in associated files

Once the implicit use of module.h is prevented, these files will
fail to find the stat.h header content.

Fix up the implicit usage expectations in advance of the cleanup.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
f2815f68dabbb373fd1c9f0fd4a609d486697c2b 10-Aug-2011 Subhash Jadavani <subhashj@codeaurora.org> mmc: sd: Handle SD3.0 cards not supporting UHS-I bus speed mode

Here is Essential conditions to indicate Version 3.00 Card
(SD_SPEC=2 and SD_SPEC3=1) :
(1) The card shall support CMD6
(2) The card shall support CMD8
(3) The card shall support CMD42
(4) User area capacity shall be up to 2GB (SDSC) or 32GB (SDHC)
User area capacity shall be more than or equal to 32GB and
up to 2TB (SDXC)
(5) Speed Class shall be supported (SDHC or SDXC)

So even if SD card doesn't support any of the newly defined
UHS-I bus speed mode, it can advertise itself as SD3.0 cards
as long as it supports all the essential conditions of
SD3.0 cards. Given this, these type of cards should atleast
run in High Speed mode @50MHZ if it supports HS.

But current initialization sequence for SD3.0 cards is
such that these non-UHS-I SD3.0 cards runs in Default
Speed mode @25MHz.

This patch makes sure that these non-UHS-I SD3.0 cards run
in High Speed Mode @50MHz.

Tested this patch with SanDisk Extreme SDHC 8GB Class 10 card.

Reported-by: "Hiremath, Vaibhav" <hvaibhav@ti.com>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
a3c76eb9d4a1e68a69dd880cf0bcb8a52418b993 11-Oct-2011 Girish K S <girish.shivananjappa@linaro.org> mmc: replace printk with appropriate display macro

All the files using printk function for displaying kernel messages
in the mmc driver have been replaced with corresponding macro.

Signed-off-by: Girish K S <girish.shivananjappa@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
44669034815a7ad263542ac605c581a10b22d146 15-Sep-2011 Stefan Nilsson XK <stefan.xk.nilsson@stericsson.com> mmc: core: Set correct bus mode before card init

Earlier all cards where initiated with bus mode set as OPENDRAIN, and then
later switched to PUSHPULL. According to the MMC/SD/SDIO specifications
only MMC cards use OPENDRAIN during init. For both SD and SDIO the bus
mode shall be PUSHPULL before attempting to init the card.

The consequence of having incorrect bus mode can lead to not being able
to detect the card. Therefore the default behavior have now been changed
to PUSHPULL in mmc_power_up, and will only be temporarily switched when
trying to attach or init a MMC card.

Signed-off-by: Stefan Nilsson XK <stefan.xk.nilsson@stericsson.com>
Signed-off-by: Ulf HANSSON <ulf.hansson@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
7f7e4129c23f0419257184dff6fec89d2d5a8964 21-Sep-2011 Ulf Hansson <ulf.hansson@stericsson.com> mmc: core: Fix hangs related to insert/remove of cards

During a rescan operation mmc_attach(sd|mmc|sdio) functions are
called. The error handling in these function can trigger a detach
of the bus, which also meant a power off. This is not notified by
the rescan operation which then continues to the next attach function.

If a power off has been done, the framework must never send any
new commands to the host driver, without first doing a new power up.
This will most likely trigger any host driver to hang.

Moving power off out of detach and instead handle power off
separately when it is actually needed, solves the issue.

Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: <stable@kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
93c712f99d8e412b2d297edfe9f59b90636897c1 08-Aug-2011 Subhash Jadavani <subhashj@codeaurora.org> mmc: sd: UHS-I bus speed should be set last in UHS initialization

mmc_sd_init_uhs_card function sets the driver type, current limit
and bus speed mode on card as well as on host controller side.

Currently bus speed mode is set by sending CMD6 to card and
immediately setting the timing mode in host controller. But
then before initiating tuning sequence, it also tries to set
current limit by sending CMD6 to card which results in data
timeout errors in controller if bus speed mode is SDR50/SDR104 mode.

So basically bus speed mode should be set only after current limit
is set in the card and immediately after setting the bus speed mode,
tuning sequence should be initiated.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: Arindam Nath <arindam.nath@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
ca8e99b32e3863c98ac958617cc157a00bf445b8 06-Jul-2011 Philip Rakity <prakity@marvell.com> mmc: core: Set non-default Drive Strength via platform hook

Non default Drive Strength cannot be set automatically. It is a function
of the board design and only if there is a specific platform handler can
it be set. The platform handler needs to take into account the board
design. Pass to the platform code the necessary information.

For example: The card and host controller may indicate they support HIGH
and LOW drive strength. There is no way to know what should be chosen
without specific board knowledge. Setting HIGH may lead to reflections
and setting LOW may not suffice. There is no mechanism (like ethernet
duplex or speed pulses) to determine what should be done automatically.

If no platform handler is defined -- use the default value.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Reviewed-by: Arindam Nath <arindam.nath@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
f0d89972b01798cf9d245dfa1cacfa0ee78a3593 23-May-2011 Andrei Warkentin <andreiw@motorola.com> mmc: core: Block CMD23 support for UHS104/SDXC cards.

SD cards operating at UHS104 or better support SET_BLOCK_COUNT.

Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Reviewed-by: Arindam Nath <arindam.nath@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
261bbd463a091b939770255d559bbc89b1bad568 13-May-2011 Philip Rakity <prakity@marvell.com> mmc: core: eMMC signal voltage does not use CMD11

eMMC chips do not use CMD11 when changing voltage. Add extra
argument to call to indicate if CMD11 needs to be sent.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Reviewed-by: Arindam Nath <arindam.nath@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
4d55c5a13a189a80d40383f02c8026f9a87d7c87 04-May-2011 Arindam Nath <arindam.nath@amd.com> mmc: sdhci: enable preset value after uhs initialization

According to the Host Controller spec v3.00, setting Preset Value Enable
in the Host Control2 register lets SDCLK Frequency Select, Clock Generator
Select and Driver Strength Select to be set automatically by the Host
Controller based on the UHS-I mode set. This patch enables this feature.
Since Preset Value Enable makes sense only for UHS-I cards, we enable this
feature after successfull UHS-I initialization. We also reset Preset Value
Enable next time before initialization.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
b513ea250eb7c36a8afb3df938d632ca6b4df7cd 04-May-2011 Arindam Nath <arindam.nath@amd.com> mmc: sd: add support for tuning during uhs initialization

Host Controller needs tuning during initialization to operate SDR50
and SDR104 UHS-I cards. Whether SDR50 mode actually needs tuning is
indicated by bit 45 of the Host Controller Capabilities register.
A new command CMD19 has been defined in the Physical Layer spec
v3.01 to request the card to send tuning pattern.

We enable Buffer Read Ready interrupt at the very begining of tuning
procedure, because that is the only interrupt generated by the Host
Controller during tuning. We program the block size to 64 in the
Block Size register. We make sure that DMA Enable and Multi Block
Select in the Transfer Mode register are set to 0 before actually
sending CMD19. The tuning block is sent by the card to the Host
Controller using DAT lines, so we set Data Present Select (bit 5) in
the Command register. The Host Controller is responsible for doing
the verfication of tuning block sent by the card at the hardware
level. After sending CMD19, we wait for Buffer Read Ready interrupt.
In case we don't receive an interrupt after the specified timeout
value, we fall back on fixed sampling clock by setting Execute
Tuning (bit 6) and Sampling Clock Select (bit 7) of Host Control2
register to 0. Before exiting the tuning procedure, we disable Buffer
Read Ready interrupt and re-enable other interrupts.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
3a3035114307cd55e024662bb295a87b849f0bd4 04-May-2011 Arindam Nath <arindam.nath@amd.com> mmc: sd: report correct speed and capacity of uhs cards

Since only UHS-I cards respond with S18A set in response to ACMD41,
we set the card as ultra-high-speed after successfull initialization.
We need to decide whether a card is SDXC based on the C_SIZE field
of CSDv2.0 register. According to Physical Layer spec v3.01, the
minimum value of C_SIZE for SDXC card is 00FFFFh.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
5371c927bcd06a5c9dd6785bab2d452b87d9abc6 04-May-2011 Arindam Nath <arindam.nath@amd.com> mmc: sd: set current limit for uhs cards

We decide on the current limit to be set for the card based on the
Capability of Host Controller to provide current at 1.8V signalling,
and the maximum current limit of the card as indicated by CMD6
mode 0. We then set the current limit for the card using CMD6 mode 1.
As per the Physical Layer Spec v3.01, the current limit switch is
only applicable for SDR50, SDR104, and DDR50 bus speed modes. For
other UHS-I modes, we set the default current limit of 200mA.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
49c468fcf878d2c86e31920cf54aa90c88418a66 04-May-2011 Arindam Nath <arindam.nath@amd.com> mmc: sd: add support for uhs bus speed mode selection

This patch adds support for setting UHS-I bus speed mode during UHS-I
initialization procedure. Since both the host and card can support
more than one bus speed, we select the highest speed based on both of
their capabilities. First we set the bus speed mode for the card using
CMD6 mode 1, and then we program the host controller to support the
required speed mode. We also set High Speed Enable in case one of the
UHS-I modes is selected. We take care to reset SD clock before setting
UHS mode in the Host Control2 register, and then re-enable it as per
the Host Controller spec v3.00. We then set the clock frequency for
the UHS-I mode selected.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
d6d50a15a2897d4133d536dd4343b5cf21163db3 04-May-2011 Arindam Nath <arindam.nath@amd.com> mmc: sd: add support for driver type selection

This patch adds support for setting driver strength during UHS-I
initialization procedure. Since UHS-I cards set S18A (bit 24) in
response to ACMD41, we use this as a base for UHS-I initialization.
We modify the parameter list of mmc_sd_get_cid() so that we can
save the ROCR from ACMD41 to check whether bit 24 is set.

We decide whether the Host Controller supports A, C, or D driver
type depending on the Capabilities register. Driver type B is
suported by default. We then set the appropriate driver type for
the card using CMD6 mode 1. As per Host Controller spec v3.00, we
set driver type for the host only if Preset Value Enable in the
Host Control2 register is not set. SDHCI_HOST_CONTROL has been
renamed to SDHCI_HOST_CONTROL1 to conform to the spec.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
013909c4ffd16ded4895528b856fd8782df04dc6 04-May-2011 Arindam Nath <arindam.nath@amd.com> mmc: sd: query function modes for uhs cards

SD cards which conform to Physical Layer Spec v3.01 can support
additional Bus Speed Modes, Driver Strength, and Current Limit
other than the default values. We use CMD6 mode 0 to read these
additional card functions. The values read here will be used
during UHS-I initialization steps.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
f2119df6b764609af4baceb68caf1e848c1c8aa7 04-May-2011 Arindam Nath <arindam.nath@amd.com> mmc: sd: add support for signal voltage switch procedure

Host Controller v3.00 adds another Capabilities register. Apart
from other things, this new register indicates whether the Host
Controller supports SDR50, SDR104, and DDR50 UHS-I modes. The spec
doesn't mention about explicit support for SDR12 and SDR25 UHS-I
modes, so the Host Controller v3.00 should support them by default.
Also if the controller supports SDR104 mode, it will also support
SDR50 mode as well. So depending on the host support, we set the
corresponding MMC_CAP_* flags. One more new register. Host Control2
is added in v3.00, which is used during Signal Voltage Switch
procedure described below.

Since as per v3.00 spec, UHS-I supported hosts should set S18R
to 1, we set S18R (bit 24) of OCR before sending ACMD41. We also
need to set XPC (bit 28) of OCR in case the host can supply >150mA.
This support is indicated by the Maximum Current Capabilities
register of the Host Controller.

If the response of ACMD41 has both CCS and S18A set, we start the
signal voltage switch procedure, which if successfull, will switch
the card from 3.3V signalling to 1.8V signalling. Signal voltage
switch procedure adds support for a new command CMD11 in the
Physical Layer Spec v3.01. As part of this procedure, we need to
set 1.8V Signalling Enable (bit 3) of Host Control2 register, which
if remains set after 5ms, means the switch to 1.8V signalling is
successfull. Otherwise, we clear bit 24 of OCR and retry the
initialization sequence. When we remove the card, and insert the
same or another card, we need to make sure that we start with 3.3V
signalling voltage. So we call mmc_set_signal_voltage() with
MMC_SIGNAL_VOLTAGE_330 set so that we are back to 3.3V signalling
voltage before we actually start initializing the card.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
ce1014965ae2538e7447b19879bd0e8109690b79 10-Feb-2011 Mark Brown <broonie@opensource.wolfsonmicro.com> mmc: Ensure prototypes for SD API are visible in sd.c

So we know the implementation and prototypes agree with each other.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
807e8e40673d9628fa7dcdd14423424b4ee5f43b 03-Jan-2011 Andy Ross <andy.ross@windriver.com> mmc: Fix sd/sdio/mmc initialization frequency retries

Rewrite and clean up mmc_rescan() to properly retry frequencies lower
than 400kHz. Failures can happen both in sd_send_* calls and
mmc_attach_*. Break out "mmc_rescan_try_freq" from the frequency
selection loop. Symmetrize claim/release logic in mmc_attach_* API,
and move the sd_send_* calls there to make mmc_rescan easier to read.

Signed-off-by: Andy Ross <andy.ross@windriver.com>
Reviewed-and-Tested-by: Hein Tibosch <hein_tibosch@yahoo.es>
Reviewed-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
8f230f454fe04ba326ffaead3a6b88dcf44eaf4b 08-Dec-2010 Takashi Iwai <tiwai@suse.de> mmc: Add support for JMicron 388 SD/MMC controller

JMicron 388 SD/MMC combo controller supports the 1.8V low-voltage for
SD, but MMC doesn't work with the low-voltage, resulting in an error
at probing.

This patch adds the support for multiple voltage mask per device type,
so that SD works with 1.8V while MMC forces 3.3V. Here new ocr_avail_*
fields for each device are introduced, so that the actual OCR mask is
switched dynamically.

Also, the restriction of low-voltage in core/sd.c is removed when the
bit is allowed explicitly via ocr_avail_sd mask.

This patch was rewritten from scratch based on Aries' original code.

Signed-off-by: Aries Lee <arieslee@jmicron.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
12ae637f081a7a05144af65802a7b492b9162660 02-Oct-2010 Ohad Ben-Cohen <ohad@wizery.com> mmc: propagate power save/restore ops return value

Allow power save/restore and their relevant mmc_bus_ops handlers
exit with a return value.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Tested-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
71d7d3d190fe77588269a8febf93cd739bd91eb3 27-Sep-2010 Matt Fleming <matt@console-pimps.org> mmc: Add helper function to check if a card is removable

There are two checks that need to be made when determining whether a
card is removable. A host controller may set MMC_CAP_NONREMOVABLE if the
controller does not support removing cards (e.g. eMMC), in which case
the card is physically non-removable. Also the 'mmc_assume_removable'
module parameter can be configured at module load time, in which case
the card may be logically non-removable.

A helper function keeps the logic in one place so that code always
checks both conditions.

Because this new function is likely to be called from modules we now
need to export the mmc_assume_removable symbol.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
dfe86cba7676d58db8de7e623f5e72f1b0d3ca35 11-Aug-2010 Adrian Hunter <adrian.hunter@nokia.com> mmc: add erase, secure erase, trim and secure trim operations

SD/MMC cards tend to support an erase operation. In addition, eMMC v4.4
cards can support secure erase, trim and secure trim operations that are
all variants of the basic erase command.

SD/MMC device attributes "erase_size" and "preferred_erase_size" have been
added.

"erase_size" is the minimum size, in bytes, of an erase operation. For
MMC, "erase_size" is the erase group size reported by the card. Note that
"erase_size" does not apply to trim or secure trim operations where the
minimum size is always one 512 byte sector. For SD, "erase_size" is 512
if the card is block-addressed, 0 otherwise.

SD/MMC cards can erase an arbitrarily large area up to and
including the whole card. When erasing a large area it may
be desirable to do it in smaller chunks for three reasons:

1. A single erase command will make all other I/O on the card
wait. This is not a problem if the whole card is being erased, but
erasing one partition will make I/O for another partition on the
same card wait for the duration of the erase - which could be a
several minutes.

2. To be able to inform the user of erase progress.

3. The erase timeout becomes too large to be very useful.
Because the erase timeout contains a margin which is multiplied by
the size of the erase area, the value can end up being several
minutes for large areas.

"erase_size" is not the most efficient unit to erase (especially for SD
where it is just one sector), hence "preferred_erase_size" provides a good
chunk size for erasing large areas.

For MMC, "preferred_erase_size" is the high-capacity erase size if a card
specifies one, otherwise it is based on the capacity of the card.

For SD, "preferred_erase_size" is the allocation unit size specified by
the card.

"preferred_erase_size" is in bytes.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Madhusudhan Chikkature <madhu.cr@ti.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ben Gardiner <bengardiner@nanometrics.ca>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
71578a1eaa7b8b9bd3efc9c97d77ef2b63d5dc2b 11-Aug-2010 Michal Miroslaw <mirq-linux@rere.qmqm.pl> mmc: split mmc_sd_init_card()

This series adds support for SD combo cards to MMC/SD driver stack.

SD combo consists of SD memory and SDIO parts in one package. Since the
parts have a separate SD command sets, after initialization, they can be
treated as independent cards on one bus.

Changes are divided into two patches. First is just moving initialization
code around so that SD memory part init can be called from SDIO init.
Second patch is a proper change enabling SD memory along SDIO. I tried to
move as much no-op changes to the first patch so that it's easier to
follow the required changes to initialization flow for SDIO cards.

This is based on Simplified SDIO spec v.2.00. The init sequence is
slightly modified to follow current SD memory init implementation.
Command sequences, assuming SD memory and SDIO indeed ignore unknown
commands, are the same as before for both parts.

This patch:

Prepare for SD-combo (IO+mem) support by splitting SD memory
card init and related functions.

Signed-off-by: Michal Miroslaw <mirq-linux@rere.qmqm.pl>
Cc: Adrian Hunter <adrian.hunter@nokia.com>
Cc: Chris Ball <cjb@laptop.org>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
5a0e3ad6af8660be21ca98a971cd00f331318c05 24-Mar-2010 Tejun Heo <tj@kernel.org> include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
bd68e0838fe85794b06892054772fa013a8d1986 15-Dec-2009 Ben Hutchings <ben@decadent.org.uk> mmc: add module parameter to set whether cards are assumed removable

Some people run general-purpose distribution kernels on netbooks with
a card that is physically non-removable or logically non-removable
(e.g. used for /home) and cannot be cleanly unmounted during suspend.
Add a module parameter to set whether cards are assumed removable or
non-removable, with the default set by CONFIG_MMC_UNSAFE_RESUME.

In general, it is not possible to tell whether a card present in an MMC
slot after resume is the same that was there before suspend. So there are
two possible behaviours, each of which will cause data loss in some cases:

CONFIG_MMC_UNSAFE_RESUME=n (default): Cards are assumed to be removed
during suspend. Any filesystem on them must be unmounted before suspend;
otherwise, buffered writes will be lost.

CONFIG_MMC_UNSAFE_RESUME=y: Cards are assumed to remain present during
suspend. They must not be swapped during suspend; otherwise, buffered
writes will be flushed to the wrong card.

Currently the choice is made at compile time and this allows that to be
overridden at module load time.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Wouter van Heyst <larstiq@larstiq.dyndns.org>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
95cdfb72b9bc568803f395c266152c71b034b461 23-Sep-2009 Nicolas Pitre <nico@fluxnic.net> mmc: propagate error codes back from bus drivers' suspend/resume methods

Especially for SDIO drivers which may have special conditions/errors to
report, it is a good thing to relay the returned error code back to upper
layers.

This also allows for the rationalization of the resume path where code to
"remove" a no-longer-existing or replaced card was duplicated into the
MMC, SD and SDIO bus drivers.

In the SDIO case, if a function suspend method returns an error, then all
previously suspended functions are resumed and the error returned. An
exception is made for -ENOSYS which the core interprets as "we don't
support suspend so just kick the card out for suspend and return success".

When resuming SDIO cards, the core code only validates the manufacturer
and product IDs to make sure the same kind of card is still present before
invoking functions resume methods. It's the function driver's
responsibility to perform further tests to confirm that the actual same
card is present (same MAC address, etc.) and return an error otherwise.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
d08ebeddfb3293fa4bdfca9c610daf1e8ec8b233 23-Sep-2009 Wolfgang Muees <wolfgang.mues@auerswald.de> mmc_spi: fail gracefully if host or card do not support the switch command

Some time ago, I have send a patch to the mmc_spi subsystem changing the
error codes. This was after a discussion with Pierre about using EINVAL
only for non-recoverable errors. This patch was accepted as

http://git.kernel.org/linus/fdd858db7113ca64132de390188d7ca00701013d

Unfortunately, several weeks later, I realized that this patch has opened
a little can of worms because there are SD cards on the market which

a) claim that they support the switch command
AND
b) refuse to execute this command if operating in SPI mode.

So, such a card would get unusuable in an embedded linux system in SPI
mode, because the init sequence terminates with an error.

This patch adds the missing error codes to the caller of the switch
command and restores the old behaviour to fail gracefully if these
commands can not execute.

Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Cc: <linux-mmc@vger.kernel.org>
Cc: <stable@kernel.org> [2.6.31.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
eae1aeeed852aae37621b82a9e7f6c05096a18fd 23-Sep-2009 Adrian Hunter <adrian.hunter@nokia.com> mmc: add ability to save power by powering off cards

Power can be saved by powering off cards that are not in use. This is
similar to suspend / resume except it is under the control of the driver,
and does not require any power management support. It can only be used
when the driver can monitor whether the card is removed, otherwise it is
unsafe. This is possible because, unlike suspend, the driver still
receives card detect and / or cover switch interrupts.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
9feae246963c648b212abad0f0eb8938de5f5fe5 23-Sep-2009 Adrian Hunter <adrian.hunter@nokia.com> mmc: add MMC_CAP_NONREMOVABLE host capability

eMMC's are not removable, so unsafe resume is OK always.

To permit this a new host capability MMC_CAP_NONREMOVABLE has been added
and suspend / resume updated accordingly.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
a4dbd6740df0872cdf0a86841f75beec8381964d 24-Jun-2009 David Brownell <dbrownell@users.sourceforge.net> driver model: constify attribute groups

Let attribute group vectors be declared "const". We'd
like to let most attribute metadata live in read-only
sections... this is a start.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
9d9f25c036dd584db175552a7d162403d3ab54b3 07-Apr-2009 Wolfgang Muees <wolfgang.mues@auerswald.de> mmc_spi: do not check CID and CSD blocks with CRC16

Some cards are not able to calculate a valid CRC16 value
for CID and CSD reads (CRC for 512 byte data blocks is OK).
By moving the CRC enable after the read of CID and CSD, these
cards can be used. This patch was tested with a faulty 8 GByte
takeMS Class 6 SDHC card. This patch was suggested by
Pierre Ossman.

Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>
8769392b1918ec70ab62eebc82e06c47c12f8304 17-Jun-2008 Deepak Saxena <dsaxena@plexity.net> MMC: Trivial comment cleanup

Make the variable name in the comments match the actual name
of the variable.

Signed-off-by: Deepak Saxena <dsaxena@laptop.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
08f80bb5196517a0dfe50dc7c10f234c0ff2f0e8 17-Jun-2008 Anton Vorontsov <avorontsov@ru.mvista.com> mmc: change .get_ro() callback semantics

Now get_ro() callback must return 0/1 values for its logical states, and
negative errno values in case of error. If particular host instance doesn't
support RO/WP switch, it should return -ENOSYS.

This patch changes some hosts in two ways:

1. Now functions should be smart to not return negative values in
"RO asserted" case (particularly gpio_ calls could return negative
values for the outermost GPIOs).

Also, board code usually passes get_ro() callbacks that directly return
gpioreg & bit result, so at91_mci, imxmmc, pxamci and mmc_spi's get_ro()
handlers need take special care when returning platform's values to the
mmc core.

2. In case of host instance didn't implement get_ro() callback, it should
really return -ENOSYS and let the mmc core decide what to do about it
(mmc core thinks the same way as the hosts, so it isn't functional
change).

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
51ec92e295d563dd5712d198a7e46c2ae5ccccb2 21-Mar-2008 Pierre Ossman <drzeus-list@drzeus.cx> mmc: use sysfs groups to handle conditional attributes

Suppressing uevents turned out to be a bad idea as it screws up the
order of events, making user space very confused. Change the system to
use sysfs groups instead.

This is a regression that, for some odd reason, has gone unnoticed for
some time. It confuses hal so that the block devices (which have the
mmc device as a parent) are not registered. End result being that
desktop magic when cards are inserted won't work.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
af51715079e7fb6b290e1881d63d815dc4de5011 08-Aug-2007 David Brownell <david-b@pacbell.net> MMC core learns about SPI

Teach the MMC/SD/SDIO core about using SPI mode.

- Use mmc_host_is_spi() so enumeration works through SPI signaling
and protocols, not just the native versions.

- Provide the SPI response type flags with each request issued,
including requests from the new lock/unlock code.

- Understand that cmd->resp[0] and mmc_get_status() results for SPI
return different values than for "native" MMC/SD protocol; this
affects resetting, checking card lock status, and some others.

- Understand that some commands act a bit differently ... notably:
* OP_COND command doesn't return the OCR
* APP_CMD status doesn't have an R1_APP_CMD analogue

Those changes required some new and updated primitives:

- Provide utilities to access two SPI-only requests, and one
request that wasn't previously needed:
* mmc_spi_read_ocr() ... SPI only
* mmc_spi_set_crc() ... SPI only (override by module parm)
* mmc_send_cid() ... for use without broadcast mode

- Updated internal routines:
* Previous mmc_send_csd() modified into mmc_send_cxd_native();
it uses native "R2" responses, which include 16 bytes of data.
* Previous mmc_send_ext_csd() becomes new mmc_send_cxd_data()
helper for command-and-data access
* Bugfix to that mmc_send_cxd_data() code: dma-to-stack is
unsafe/nonportable, so kmalloc a bounce buffer instead.

- Modified mmc_send_ext_csd() now uses mmc_send_cxd_data() helper

- Modified mmc_send_csd(), and new mmc_spi_send_cid(), routines use
those helper routines based on whether they're native or SPI

The newest categories of cards supported by the MMC stack aren't expected
to work yet with SPI: MMC or SD cards with over 4GB data, and SDIO.
All those cards support SPI mode, so eventually they should work too.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
d84075c8aed771d47d7ac6e96b098559da361c25 09-Aug-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: replace BUG_ON with WARN_ON

Replace all cases of BUG_ON with WARN_ON where there is a chance
(with varying degrees of slim) that the kernel can continue without
incidence.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
adf66a0dc5e8be8d4e64f3c2114f9b175558235b 22-Jul-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: improve error code feedback

Now that we use "normal" error codes, improve the reporting and response
to error codes in the core.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
17b0429dde9ab60f9cee8e07ab28c7dc6cfe6efd 22-Jul-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: remove custom error codes

Convert the MMC layer to use standard error codes and not its own,
incompatible values.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
facba9179e3cd5fa91ff40bbc555c5cd4c101092 24-Jul-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: add missing printk levels

Some printk:s were missing an explicit level.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
109b5bed18441599b5ab0e1f3623efa5715a4703 23-Jul-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: be more verbose about card insertions/removal

Let the user know that the kernel actually detected the card
by printing some basic information in dmesg.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2986d0bf23d97d68804ccfa80965073ccf1af242 22-Jul-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: Don't hold lock when releasing an added card

When the card has been added to the device model, it might be bound
to a card driver. Therefore, we have to release the host lock when
trying to remove it as we otherwise might deadlock with the driver.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
70f10482c668301c483acded13bf68780ad352b9 11-Jul-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: update header file paths

Make sure all headers in the files reflect their true position
in the tree.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
4101c16a910b15afd190c6bc7d45864461cf5c25 19-May-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: refactor bus operations

Move bus operations to its own file for the sake of clarity. Also
delegate sysfs attributes to bus handlers in preparation for other
more exotic types.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
c3bff2ec10b8bf2f53c954e370f9bdae93064472 13-Jun-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: get back read-only switch function

Somehow the code to read the read-only switch of SD cards got lost
in the reorganisation.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
3373c0ae6a51085b10a95fd9d2214a9995ef7563 31-May-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: don't call switch on old cards

Make sure we don't call the switch function on cards too old to
support it. They should just ignore it, but some have been reported
to lock up instead.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
71651297a448289353b2493c6c3c183f9be7be7c 06-Jun-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: fix broken if clause

Fix a broken if clause which was causing SD cards to go into
4-bit mode even if the host did not support it.

(Reported by David Brownell and Marc Pignat)

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
bd766312618d2ecc85bce663f95faec601447ecb 01-May-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: remove old card states

Remove card states that no longer make any sense.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
6abaa0c9fec563538f2a28a682af8c89bb9b125c 01-May-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: support unsafe resume of cards

Since many have the system root on MMC/SD we must allow some foot
shooting when it comes to resume.

We cannot detect if a card is removed and reinserted during suspend,
so the safe approach would be to assume it was, avoiding potential
filesystem corruption. This will of course not work if you cannot
release the card before suspend.

This commit adds a compile time option that makes the MMC layer
assume the card wasn't touched if it is redetected upon resume.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
1addfcdbe4b23a20f28a097c2469d9f0c21bef23 01-May-2007 Pierre Ossman <drzeus@drzeus.cx> mmc: break apart switch function

Break apart the SD switch function into one that reads the capabilities
and one that acts on them.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
55556da01284af8c2174b786b3eca8e11301b656 17-Mar-2007 Philip Langdale <philipl@overt.org> MMC: Fix handling of low-voltage cards

Fix handling of low voltage MMC cards.

The latest MMC and SD specs both agree that support for
low-voltage operations is indicated by bit 7 in the OCR.
The MMC spec states that the low voltage range is
1.65-1.95V while the SD spec leaves the actual voltage
range undefined - meaning that there is still no such
thing as a low voltage SD card.

However, an old Sandisk spec implied that bits 7.0
represented voltages below 2.0V in 1V or 0.5V increments,
and the code was accordingly written with that expectation.

This confusion meant that host drivers attempting to support
the typical low voltage (1.8V) would set the wrong bits in
the host OCR mask (usually bits 5 and/or 6) resulting in the
the low voltage mode never being used.

This change corrects the low voltage range and adds sanity
checks on the reserved bits (0-6) and for SD cards that
claim to support low-voltage operations.

Signed-off-by: Philip Langdale <philipl@overt.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
7ea239d9e6d6993469a6a8ca83ff23834dfc3fce 31-Dec-2006 Pierre Ossman <drzeus@drzeus.cx> mmc: add bus handler

Delegate protocol handling to "bus handlers". This allows the core to
just handle the task of arbitrating the bus. Initialisation and
pampering of cards is now done by the different bus handlers.

This design also allows MMC and SD (and later SDIO) to be more cleanly
separated, allowing easier maintenance.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>