mmc: sdhci-pci: add runtime pm support

Ths patch allows runtime PM for sdhci-pci, runtime suspending after
inactivity of 50ms and ensuring runtime resume before SDHC registers
are accessed.  During runtime suspend, interrupts are masked.
The host controller state is restored at runtime resume.

For Medfield, the host controller's card detect mechanism is
supplanted by an always-on GPIO which provides for card detect wake-up.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: fix vmmc handling

Presently the vmmc regulator is enabled when the host
controller is added and disabled when it is removed.
However, the vmmc regulator should be under the control
of the upper layers via ->set_ios().  Make it so.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: prevent card detection activity for non-removable cards

Do not enable card detection interrupts for non-removable cards.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci-pci: remove SDHCI_QUIRK2_OWN_CARD_DETECTION

Even if a driver provides separate card detection, an interrupt
is still needed to abort mmc requests that are in progress.
SDHCI_QUIRK2_OWN_CARD_DETECTION prevents that, so remove it.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: Deal with failure case in sdhci_suspend_host

If there are errors happened in sdhci_suspend_host, handle it so that
when the function returns with an error, the host's behaviour is the
same before this function call, e.g. card detection is enabled and
tuning timer is active, etc.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Aaron Lu <aaron.lu@amd.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: host: Adds support for eMMC 4.5 HS200 mode

This patch adds support for the HS200 mode on the host side.
Also enables the tuning feature required when the HS200 mode
is selected.

Signed-off-by: Girish K S <girish.shivananjappa@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: restore the enabled dma when do reset all

If dma is enabled, it'll be cleared when reset all is performed, this can
be observed on some platforms, such as P2041 which has a version 2.3
controller, but platform like P4080 which has a version 2.2 controller,
does not suffer this, so we will check if the dma is enabled, we should
restore it after reset all.

Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: add quirk for keeping card power during suspend

Add quirk SDHCI_QUIRK2_HOST_OFF_CARD_ON to cater for the case when the
card keeps power during suspend but the host controller does not i.e.
the card power is not controlled by the host controller.  In that
case, the controller must be fully reset on resume.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: check interrupt flags in ISR again

When using MSI it is possible that a new MSI is sent while an earlier
MSI is currently handled. In this case SDHCI_INT_STATUS only contains
SDHCI_INT_RESPONSE and the ISR would not be called again. But at the end
of the ISR SDHCI_INT_DATA_END is now also pending which would be ignored.

Fix this by rereading the interrupt flags in the ISR until no interrupt
we care is pending.

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: Prevent 1.8V switch for SD hosts that don't support UHS modes.

The driver should not try to switch to 1.8V when the SD 3.0 host
controller does not have any UHS capabilities bits set (SDR50, DDR50
or SDR104). See page 72 of "SD Specifications Part A2 SD Host
Controller Simplified Specification Version 3.00" under
"1.8V Signaling Enable". Instead of setting SDR12 and SDR25 in the host
capabilities data structure for all V3.0 host controllers, only set them
if SDR104, SDR50 or DDR50 is set in the host capabilities register. This
will prevent the switch to 1.8V later.

Signed-off-by: Al Cooper <acooper@gmail.com>
Acked-by: Arindam Nath <arindam.nath@amd.com>
Acked-by: Philip Rakity <prakity@marvell.com>
Acked-by: Girish K S <girish.shivananjappa@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: refine non-removable card checking for card detection

Commit c79396c191bc19 ("mmc: sdhci: prevent card detection activity
for non-removable cards") disables card detection where the cards
are marked as non-removable.

This makes sense, but the implementation detail of calling
mmc_card_is_removable() causes some problems, because
mmc_card_is_removable() is overloaded with CONFIG_MMC_UNSAFE_RESUME
semantics.

In the OLPC XO case, we need CONFIG_MMC_UNSAFE_RESUME because our root
filesystem is stored on SD, but we also have external SD card slots
where we want automatic card detection.

Refine the check to only apply to hosts marked as MMC_CAP_NONREMOVABLE,
which is defined to mean that the card is *really* nonremovable. This
could be revisited in future if we find a way to improve
CONFIG_MMC_UNSAFE_RESUME semantics.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Acked-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
[stable@: please apply to 3.3-stable]
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: if MAX_CURRENT is 0, try getting current from regulator

The sd host controller spec indicates the the MAX_CURRENT value may
be returned as 0.  In this case other methods need to be used to
return the current.  If 0 is returned and there is a regulator,
ask the regulator for how much current is available.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Mark F. Brown <mark.brown314@gmail.com>
Reviewed-by: Aaron Lu <aaron.lu@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: only support voltage (vdd) that regulator agrees with

If we are using a regulator the SD Host Controller and the
regulator should agree about the voltages supported.  Use
the common subset that is supported.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: Allow caps[1] to be set via SDHCI_QUIRK_MISSING_CAPS

Currently only the capability_0 register can be set if
SDHCI_QUIRK_MISSING_CAPS is defined.  This is a problem when
the capability_1 register also needs changing.  Use the quirk
SDHCI_QUIRK_MISSING_CAPS to allow both registers to be set.

Redefining caps[1] is useful when the board design does not
support 1.8v vccq so UHS modes are not available.  The code that
calls sdhci_add_host can then detect this condition and adjust
the caps so the UHS mode will not be attempted on UHS cards.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: Report failure reasons for all cases in sdhci_add_host()

For most error conditions sdhci_add_host() will print a diagnostic
message indicating why it failed but there are a few cases where this
does not happen. Add error messages in these cases to aid diagnosis.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: fix incorrect command used in tuning

For SD hosts using retuning mode 1, when retuning timer expired, it will
need to do retuning in sdhci_request before processing the actual
request. But the retuning command is fixed: cmd19 for SD card and cmd21
for eMMC card, so we can't use the original request's command to do the
tuning.

And since the tuning command depends on the card type attached to the
host, we will need to know the card type to use the correct tuning
command.

Signed-off-by: Aaron Lu <aaron.lu@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Cc: stable <stable@vger.kernel.org> [3.3+]
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: restore host settings when card is removed

Some of the host settings are affected by different cards inserted, e.g.
when an UHS-I card is inserted, the SDHCI_NEEDS_RETUING flag might be
set when the tuning timer expired and host's max_blk_count will be
reduced to make sure the data transfer for a command does not exceed 4MiB
to meet the retuning mode 1's requirement.

When the card is removed, we should restore the original setting of the
host since we can't be sure the next card being inserted will still be
an UHS-I card that needs tuning. The original setting include its
max_blk_count and no set of the flag of SDHCI_NEEDS_RETUNING.

Signed-off-by: Aaron Lu <aaron.lu@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: Introduce new flag SDHCI_USING_RETUNING_TIMER

Add a new flag of SDHCI_USING_RETUNING_TIMER to represent if the host
is using a retuning timer for the card inserted.

This flag is set when the host does tuning the first time for the card
and the host's retuning mode is 1. This flag is used afterwards whenever
needs to decide if the host is currently using a retuning timer.

This flag is cleared when the card is removed in sdhci_reinit.

The set/clear of the flag and the start/stop of the retuning timer is
associated with the card's init/remove time, so there is no need to
touch it when the host is to be removed as at that time the card should
have already been removed.

Signed-off-by: Aaron Lu <aaron.lu@amd.com>
Reviewed-by: Girish K S <girish.shivananjappa@linaro.org>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: poll for card even when card is logically unremovable

The Marvell CaFe is now marked as having bad card detection to fix
a problem during system resume.

Now on the OLPC XO-1 we are facing the issue that the card is marked
as logically unremovable (via MMC_UNSAFE_RESUME), which means that
mmc_card_is_removable considers the card non-removable. The existing
code logic decides not to poll for card presence in this case, and
card detection is also disabled because of the quirk being set.
This means that no SD cards are detected when inserted after boot.

Refine the logic to enable card presence polling in the case when
a card is logically unremovable, only avoiding the poll in the case
when the card is physically non-removable (denoted with
MMC_CAP_NONREMOVABLE).

Signed-off-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: When a UHS switch fails, cycle power if regulator is used

Power needs to be removed from the card when switching to 1.8v fails.

If a regulator is used to control vmmc we need to turn the
regulator off and then back on otherwise power will not be
removed from the card.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Reviewed-by: Aaron Lu <aaron.lu@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>