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: NPhilip Rakity <prakity@marvell.com>
Signed-off-by: NMark F. Brown <mark.brown314@gmail.com>
Reviewed-by: NAaron Lu <aaron.lu@amd.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Extend the sh_mmcif driver to support GPIO card detection, provided by the
slot function module. The original .get_cd() platform callback is also
preserved for now.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Currently mmc host drivers have to decide whether to enable card
detection before calling mmc_add_host() -- in which case a card
insertion event can arrive before the host has been completely
initialised -- or after mmc_add_host(), in which case the initial
card detection can be problematic.

This patch adds an explicit indication of when card detection should
not be carried out. With it in place enabling card detection before
calling mmc_add_host() should be safe. Similarly, disabling it again
after calling mmc_remove_host() will avoid any races.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Add primitive OF support to the sh-mmcif driver, which also makes it
necessary to be able to run without platform data.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Add primitive support for OF to the SDHI TMIO glue, which also makes it
necessary to be able to run without platform data.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

The tmio-mmc driver is already using the generic GPIO CD handler in IRQ
mode. This patch adds support for CD polling mode and also checks for
availability of a WP GPIO.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Let SDHI platforms specify mmc_host::caps2 flags in their platform data.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Allow tmio mmc glue drivers to pass mmc_host::caps2 flags down to
the mmc layer.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Card Write-Protect pin is often implemented, using a GPIO, which makes
it simple to provide a generic handler for it.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

This prepares for the addition of further slot functions.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

A simple extension of mmc slot functions add support for CD GPIO polling
for cases where the GPIO cannot produce interrupts, or where this is not
desired for some reason.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

To handle CD and WP SD/MMC slot pins we need generic flags to specify their
polarity.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

struct mmc_host::hotplug is becoming a generic hook for slot functions.
Rename it accordingly.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Add regulator support to the sh_mmcif driver, but also preserve the current
power-callback.

Also note, that the card power is not switched off during clock gating
periods, hence there's no need to power it on every time the card is
re-activated.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviwed-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NChris Ball <cjb@laptop.org>

From the original version of sh_mmcif the .set_pwr() callback has only been
used to turn the card's power on, and the .down_pwr() callback has been
used to turn it off. .set_pwr() can be used for both these tasks, which is
also how it is implemented by the only user of this API: the SH7724 ecovec
board.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviewed-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NChris Ball <cjb@laptop.org>

With aggressive clock gating the clock can be disabled during interface
inactivity. During this time its frequency can be changed by another its
user. Therefore when the interface is activated again and the clock is
re-enabled, its frequency has to be re-read.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviewed-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NChris Ball <cjb@laptop.org>

Regardless of whether the MMC bus clock is the same as the PM clock on
this specific interface, it has to be managed separately. Its proper
management should also include enabling and disabling of the clock,
whenever the interface is becoming active or going idle respectively.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviewed-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NChris Ball <cjb@laptop.org>

A check for NULL platform data can be conveniently made in the very
beginning of probing. Replace numbered error-handling labels in .probe()
with meaningful names to make any future reorganisation simpler.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviewed-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NChris Ball <cjb@laptop.org>

Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Currently the SDHI glue for the TMIO MMC driver installs dummy .get_cd() and
.set_pwr() callbacks even if the platform didn't supply them. This is not
necessary, since the TMIO MMC driver itself checks for NULL callbacks. This
is also dubious if the platform provides a regulator for SD-card power
switching. It is better to only install those callbacks, if they are really
provided by the platform.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Currently the TMIO MMC driver derives the OCR mask from the platform data
and uses a platform callback to turn card power on and off. This patch adds
regulator support to the driver.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Liam Girdwood <lrg@ti.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Instead of delivering one static clock frequency value, read from the
hardware during probing, enable the tmio-mmc driver to re-read the
frequency dynamically.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Every time the clock is enabled after possibly being disabled, we have
to re-read its frequency and update our configuration.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

We don't have to force-enable MMC interrupts in our .probe() method,
mmc_add_host() will trigger card detection, that will enable all the
necessary interrupts.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

host->dma_ops is not valid if host->usa dma is 0 so protect
host->dma_ops reference in dw_mci_resume
Signed-off-by: NJonathan Kliegman <kliegs@chromium.org>
Acked-by: NJaehoon Chung <jh80.chung@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Add a function to get regulators, supplying card's Vdd and Vccq on a
specific host. If a Vdd supplying regulator is found, the function checks,
whether a valid OCR mask can be obtained from it. The Vccq regulator is
optional. A failure to get it is not fatal.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviwed-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NChris Ball <cjb@laptop.org>

The tmio_mmc_set_ios() function configures the MMC power, clock and bus
width. When the mmc core requests the driver to power off the card, we
inform runtime PM, that the controller can be suspended. This can lead
to the MSTP clock being turned off.

Writing to any 16-bit hardware registers with the MSTP clock off leads
to timeouts and errors being printed to the kernel log. This can occur
both when stopping the MMC clock and when configuring the bus width.

To fix this, stop the MMC clock before calling put_runtime_pm(), and
skip bus width configuration when power is off.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: NSimon Horman <horms@verge.net.au>
Acked-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

The MMC_SLEEP_AWAKE and SD_IO_SEND_OP_COND commands share the same
opcode. SD_IO_SEND_OP_COND isn't supported by the SH MMCIF, but
MMC_SLEEP_AWAKE is. Discriminate between the two commands using the
command flags, and reject SD_IO_SEND_OP_COND only.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

In the current dwmmc driver there is support for selecting IDMAC from
the menu config option. If the support for IDMAC is enabled in the menu
config and the hardware configuration register's DMA_INTERFACE field is
0, the driver will still try to do the DMA initialization.

The dw_mci_idmac_init function currently implemented returns only success
indicating that the DMA initialization is always successful. This patch
adds a check for existence of the DMA IP to allow the DMA initialization.
Signed-off-by: NGirish K S <girish.shivananjappa@linaro.org>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Tested on an OLPC XO-1.75.  (MMP2, sdhci-pxav3, CONFIG_MACH_MMP2_DT=y)
Signed-off-by: NChris Ball <cjb@laptop.org>
Acked-by: NHaojian Zhuang <haojian.zhuang@gmail.com>

Even though these aren't parsed by the MMC driver, make clear that
they're required by the OF core.  (Also, a few typo fixes.)
Signed-off-by: NChris Ball <cjb@laptop.org>

Now that we have common bindings for MMC, rewrite the individual
bindings to inherit from mmc.txt and describe their differences.
Acked-by: NStephen Warren <swarren@wwwdotorg.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

The regulator API functions we're wrapping are exported as GPL, so our
wrappers for the same functions should be too.
Reported-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

For completing any block request, MMC block driver is calling:
	spin_lock_irq(queue)
	__blk_end_request()
	spin_unlock_irq(queue)

But if we analyze the sources of latency in kernel using ftrace,
__blk_end_request() function at times may take up to 6.5ms with
spinlock held and irq disabled.

__blk_end_request() calls couple of functions and ftrace output
shows that blk_update_bidi_request() function is almost taking 6ms.
There are 2 function to end the current request: ___blk_end_request()
and blk_end_request(). Both these functions do same thing except
that blk_end_request() function doesn't take up the spinlock
while calling the blk_update_bidi_request().

This patch replaces all __blk_end_request() calls with
blk_end_request() and __blk_end_request_all() calls with
blk_end_request_all().

Testing done: 20 process concurrent read/write on sd card
and eMMC. Ran this test for almost a day on multicore system
and no errors observed.

This change is not meant for improving MMC throughput; it's basically
about becoming fair to other threads/interrupts in the system. By
holding spin lock and interrupts disabled for longer duration, we
won't allow other threads/interrupts to run at all.  Actually slight
performance degradation at file system level can be expected as we
are not holding the spin lock during blk_update_bidi_request() which
means our mmcqd thread may get preempted for other high priority
thread or any interrupt in the system.

These are performance numbers (100MB file write) with eMMC running
in DDR mode:

Without this patch:
	Name of the Test   Value   Unit
	LMDD Read Test     53.79   MBPS
	LMDD Write Test    18.86   MBPS
	IOZONE  Read Test  51.65   MBPS
	IOZONE  Write Test 24.36   MBPS

With this patch:
	Name of the Test    Value  Unit
	LMDD Read Test      52.94  MBPS
	LMDD Write Test     16.70  MBPS
	IOZONE  Read Test   52.08  MBPS
	IOZONE  Write Test  23.29  MBPS

Read numbers are fine. Write numbers are bit down (especially LMDD
write), may be because write requests normally have large transfer
size and which means there are chances that while mmcq is executing
blk_update_bidi_request(), it may get interrupted by interrupts or
other high priority thread.
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

mmc_execute_hpi should send the HPI command only once, and only
if the card is in PRG state.

According to eMMC spec, the command's completion time is
not dependent on OUT_OF_INTERRUPT_TIME. Only the transition
out of PRG STATE is guarded by OUT_OF_INTERRUPT_TIME - which
is defined to begin at the end of sending the command itself.

Specify the default timeout for the actual sending of HPI
command, and then use OUT_OF_INTERRUPT_TIME to wait for
the transition out of PRG state.
Reported-by: NAlex Lemberg <Alex.Lemberg@sandisk.com>
Signed-off-by: NVenkatraman S <svenkatr@ti.com>
Reviewed-by: NNamjae Jeon <linkinjeon@gmail.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Acked-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

GPIOs can be used in MMC/SD-card slots not only for hotplug detection, but
also to implement the write-protection pin. Rename cd-gpio helpers to
slot-gpio to make addition of further slot GPIO functions possible.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

mmc.h defines macros for most frequently used MMC opcodes. Use them instead
of hard-coded numbers.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Fix a boot regression on Mackerel boards with sh_mobile_sdhi
in existing kernels causing:

genirq: Threaded irq requested with handler=NULL and !ONESHOT for irq XXX

caused by 1c6c6952 (genirq: Reject bogus threaded irq requests).

This is backported from Guennadi's patch:
"mmc: extend and rename cd-gpio helpers to handle more slot GPIO functions"
Reported-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

This reverts commit 3d93576e(skip card initialization if
power class selection fails).
Problem has been reported when this is used with eMMC4.41
card with Tegra Platform. Till the issue is root caused,
bus width selection failure should not be treated as fatal.
Reported-by: NMarc Dietrich <marvin24@gmx.de>
Signed-Off-by: NVenkatraman S <svenkatr@ti.com>
CC: Ulf Hansson <ulf.hansson@stericsson.com>
CC: Subhash Jadavani <subhashj@codeaurora.org>
CC: Saugata Das <saugata.das@linaro.org>
Signed-off-by: NChris Ball <cjb@laptop.org>

48ddbe19 "cgroup: make css->refcnt clearing on cgroup removal
optional" allowed a css to linger after the associated cgroup is
removed.  As a css holds a reference on the cgroup's dentry, it means
that cgroup dentries may linger for a while.

Destroying a superblock which has dentries with positive refcnts is a
critical bug and triggers BUG() in vfs code.  As each cgroup dentry
holds an s_active reference, any lingering cgroup has both its dentry
and the superblock pinned and thus preventing premature release of
superblock.

Unfortunately, after 48ddbe19, there's a small window while
releasing a cgroup which is directly under the root of the hierarchy.
When a cgroup directory is released, vfs layer first deletes the
corresponding dentry and then invokes dput() on the parent, which may
recurse further, so when a cgroup directly below root cgroup is
released, the cgroup is first destroyed - which releases the s_active
it was holding - and then the dentry for the root cgroup is dput().

This creates a window where the root dentry's refcnt isn't zero but
superblock's s_active is.  If umount happens before or during this
window, vfs will see the root dentry with non-zero refcnt and trigger
BUG().

Before 48ddbe19, this problem didn't exist because the last dentry
reference was guaranteed to be put synchronously from rmdir(2)
invocation which holds s_active around the whole process.

Fix it by holding an extra superblock->s_active reference across
dput() from css release, which is the dput() path added by 48ddbe19
and the only one which doesn't hold an extra s_active ref across the
final cgroup dput().
Signed-off-by: NTejun Heo <tj@kernel.org>
LKML-Reference: <4FEEA5CB.8070809@huawei.com>
Reported-by: Nshyju pv <shyju.pv@huawei.com>
Tested-by: Nshyju pv <shyju.pv@huawei.com>
Cc: Sasha Levin <levinsasha928@gmail.com>
Acked-by: NLi Zefan <lizefan@huawei.com>