MMC_CLKGATE was once invented to save power by gating the bus clock at
request inactivity. At that time it served its purpose. The modern way to
deal with power saving for these scenarios, is by using runtime PM.

Nowadays, several host drivers have deployed runtime PM, but for those
that haven't and which still cares power saving at request inactivity,
it's certainly time to deploy runtime PM as it has been around for several
years now.

To simplify code to mmc core and thus decrease maintenance efforts, this
patch removes all code related to MMC_CLKGATE.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>

As SD Specifications Part1 Physical Layer Specification Version
3.01 says, CMD19 tuning is available for unlocked cards in transfer
state of 1.8V signaling mode. The small difference between v3.00
and 3.01 spec means that CMD19 tuning is also available for DDR50
mode.
Signed-off-by: NWeijun Yang <york.yang@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

This patch add MMC_TIMING_UHS_SDR12 and MMC_TIMING_UHS_SDR25
for mmc_ios_show to show the ios->timing if mmc card runs under
these two modes.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Some sdio wifi chips will not work properly if we try to start new
sdio-rw requests while the device is signalling that it is busy.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Add a helper function to check if an opcode is a sd-io-rw-* opcode.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The simple power sequence provider sets a value for multiple GPIOs in one
go so it is better to use the API already provided by the GPIO descriptor
API instead of open coding the same logic.
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

This patch add ios->drv_type for mmc_ios_show to show the
card's driver type.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The gpiod_get() function expands to gpiod_get_index() with index 0
so it's better to use it since is easier to read and more concise.
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

As there are no users of the __mmc_switch() API, except for the mmc core
itself, let's convert it from an exported function into an internal.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Signed-off-by: NYousong Zhou <yszhou4tech@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

As mmc_claim_host() invokes pm_runtime_get_sync() for the mmc host device,
it's important that the host is kept claimed for *all* accesses to it via
the host_ops callbacks.

In some code paths for SDIO, particularly related to the PM support,
mmc_power_off|up() is invoked without keeping the host claimed. Let's fix
these.

Moreover, mmc_start|stop_host() also invokes mmc_power_off|up() without
claiming the host, let's fix these as well.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NKishon Vijay Abraham I <kishon@ti.com>

Suppose that we got a data crc error, and it triggers the mmc_reset.
mmc_reset will call mmc_send_status to see if HW reset was supported.
before issue CMD13, it will do retune, and if EMMC was in HS400 mode,
it will reduce frequency to 52Mhz firstly, then results in card init
was doing at 52Mhz.
The mmc_send_status was originally only done for mmc_test, should drop
it. And, rename the "eMMC hardware reset" to "Reset test", as we would
also be able to use the test for SD-cards.
Signed-off-by: NChaotian Jing <chaotian.jing@mediatek.com>
Suggested-by: NAdrian Hunter <adrian.hunter@intel.com>
Fixes: bd11e8bd ("mmc: core: Flag re-tuning is needed on CRC errors")
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

When get a CRC error, start the mmc_retune, it will issue CMD19/CMD21
to do tune, assume there were 10 clock phase need to try, phase 0 to
phase 6 is ok, phase 7 to phase 9 is NG, we try it from 0 to 9, so
the last CMD19/CMD21 will get CRC error, host->need_retune was set and
cause mmc_retune was called, then dead loop of mmc_retune
Signed-off-by: NChaotian Jing <chaotian.jing@mediatek.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Fixes: bd11e8bd ("mmc: core: Flag re-tuning is needed on CRC errors")
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

When CONFIG_GPIOLIB is unset, its stubs will return -ENOSYS. That means
when the mmc core parses DT for CD/WP GPIOs via mmc_of_parse(), -ENOSYS
becomes propagated to the caller. Typically this means that the mmc host
driver fails to probe.

As the CD/WP GPIOs are already treated as optional, let's extend that to
cover the case when CONFIG_GPIOLIB is unset.
Reported-by: NMichal Simek <michal.simek@xilinx.com>
Fixes: 16b23787 ("mmc: sdhci-of-arasan: Call OF parsing for MMC")
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NMichal Simek <michal.simek@xilinx.com>
Acked-by: NVenu Byravarasu <vbyravarasu@nvidia.com>

The following panic is captured in ker3.14, but the issue still exists
in latest kernel.
---------------------------------------------------------------------
[   20.738217] c0 3136 (Compiler) Unable to handle kernel NULL pointer dereference
at virtual address 00000578
......
[   20.738499] c0 3136 (Compiler) PC is at _raw_spin_lock_irqsave+0x24/0x60
[   20.738527] c0 3136 (Compiler) LR is at _raw_spin_lock_irqsave+0x20/0x60
[   20.740134] c0 3136 (Compiler) Call trace:
[   20.740165] c0 3136 (Compiler) [<ffffffc0008ee900>] _raw_spin_lock_irqsave+0x24/0x60
[   20.740200] c0 3136 (Compiler) [<ffffffc0000dd024>] __wake_up+0x1c/0x54
[   20.740230] c0 3136 (Compiler) [<ffffffc000639414>] mmc_wait_data_done+0x28/0x34
[   20.740262] c0 3136 (Compiler) [<ffffffc0006391a0>] mmc_request_done+0xa4/0x220
[   20.740314] c0 3136 (Compiler) [<ffffffc000656894>] sdhci_tasklet_finish+0xac/0x264
[   20.740352] c0 3136 (Compiler) [<ffffffc0000a2b58>] tasklet_action+0xa0/0x158
[   20.740382] c0 3136 (Compiler) [<ffffffc0000a2078>] __do_softirq+0x10c/0x2e4
[   20.740411] c0 3136 (Compiler) [<ffffffc0000a24bc>] irq_exit+0x8c/0xc0
[   20.740439] c0 3136 (Compiler) [<ffffffc00008489c>] handle_IRQ+0x48/0xac
[   20.740469] c0 3136 (Compiler) [<ffffffc000081428>] gic_handle_irq+0x38/0x7c
----------------------------------------------------------------------
Because in SMP, "mrq" has race condition between below two paths:
path1: CPU0: <tasklet context>
  static void mmc_wait_data_done(struct mmc_request *mrq)
  {
     mrq->host->context_info.is_done_rcv = true;
     //
     // If CPU0 has just finished "is_done_rcv = true" in path1, and at
     // this moment, IRQ or ICache line missing happens in CPU0.
     // What happens in CPU1 (path2)?
     //
     // If the mmcqd thread in CPU1(path2) hasn't entered to sleep mode:
     // path2 would have chance to break from wait_event_interruptible
     // in mmc_wait_for_data_req_done and continue to run for next
     // mmc_request (mmc_blk_rw_rq_prep).
     //
     // Within mmc_blk_rq_prep, mrq is cleared to 0.
     // If below line still gets host from "mrq" as the result of
     // compiler, the panic happens as we traced.
     wake_up_interruptible(&mrq->host->context_info.wait);
  }

path2: CPU1: <The mmcqd thread runs mmc_queue_thread>
  static int mmc_wait_for_data_req_done(...
  {
     ...
     while (1) {
           wait_event_interruptible(context_info->wait,
                   (context_info->is_done_rcv ||
                    context_info->is_new_req));
     	   static void mmc_blk_rw_rq_prep(...
           {
           ...
           memset(brq, 0, sizeof(struct mmc_blk_request));

This issue happens very coincidentally; however adding mdelay(1) in
mmc_wait_data_done as below could duplicate it easily.

   static void mmc_wait_data_done(struct mmc_request *mrq)
   {
     mrq->host->context_info.is_done_rcv = true;
+    mdelay(1);
     wake_up_interruptible(&mrq->host->context_info.wait);
    }

At runtime, IRQ or ICache line missing may just happen at the same place
of the mdelay(1).

This patch gets the mmc_context_info at the beginning of function, it can
avoid this race condition.
Signed-off-by: NJialing Fu <jlfu@marvell.com>
Tested-by: NShawn Lin <shawn.lin@rock-chips.com>
Fixes: 2220eedf ("mmc: fix async request mechanism ....")
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

For some mass production of kingston eMMCs which adopt Phison's
firmware will meet an unrecoverable data conrruption occasionally
if performing trim due to a firmware bug confirmed by vendor. We
found it on Intel-C3230RK platform. So we add fixup of broken trim
for it.
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Use more compact of_property_read_bool() calls instead of the
of_find_property() calls.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

When requesting a trim for several bytes, everything up to the next
erase-group is erased. This causes data corruption.
Signed-off-by: NRobin van der Gracht <robin@protonic.nl>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

In the (not so unlikely) case that the mmc controller timeout budget is
enough for exactly one erase-group, the simplification of allowing one
sector has an enormous performance penalty. We optimize this special case
by introducing a flag that prohibits erase-group boundary crossing, so
that we can allow trimming more than one sector at a time.
Signed-off-by: NDavid Jander <david@protonic.nl>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Other subsystem buses attach PM domains during probe, but prior calling
the driver's ->probe() method. During the removal phase, detaching the PM
domain will be done after invoking the driver's ->remove() callback.

Convert the SDIO bus to follow this behavior and add error handling.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Since the ->reset() callback is implemented for SD, the ->power_restore()
callback has become redundant, let's remove it.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Since the ->reset() callback is implemented for MMC, the ->power_restore()
callback has become redundant, let's remove it.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Add the ability to set eMMC driver strength
for HS200 and HS400.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

In preparation for supporing drive strength selection
for eMMC, read the card's valid driver strengths.

Note that though the SD spec uses the term "drive strength",
the JEDEC eMMC spec uses the term "driver strength".
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

In preparation for adding drive strength support
for eMMC, add drive_strength to struct mmc_card
to record the card drive strength for UHS-I modes
and HS200 / HS400. For eMMC this will be needed
when switching between HS200 and HS400.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Make a new function out of common code used for drive
strength selection.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

In preparation for supporting also eMMC drive strength,
add the 'card' as a parameter so that the callback can
distinguish different types of cards if necessary.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Card drive strength selection uses a callback to
which a mask of supported drive strengths is passed.
Currently, the bits are checked against the values
in the SD specifications. That is not necessary
because the callback will anyway match the mask
against a valid value. Simplify by taking the mask
as is but still ensuring that the default mandatory
value (type B) is always supported.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Initialization of UHS-I modes for SD and SDIO cards
employs a callback to allow the host driver to
choose a drive strength value. Currently that
assumes the card drive strength and host driver
type must be the same value. Change to let the
callback make that decision and return both the
card drive strength and host driver type.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

IO state variable drv_type could be set during card
initialization. Consequently, it must be reset to the
default value when setting the initial state.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Since the regulator used for the SDMMC IO voltage is not expected to
draw a lot of current, most systems will probably use an inexpensive
LDO for it.  LDO regulators apparently have the feature that they
don't actively drive the voltage down--they wait for other components
in the system to drag the voltage down.  Thus they will transition
faster under heavy loads and slower under light loads.

During an SDMMC voltage change from 3.3V to 1.8V, we are almost
certainly under a light load.  To be specific:
* The regulator is hooked through pulls to CMD0-3 and DAT.  Probably
  the CMD pulls are something like 47K and the DAT is something like
  10K.
* The card is supposed to be driving DAT0-3 low during voltage change
  which will draw _some_ current, but not a lot.
* The regulator is also provided to the SDMMC host controller, but the
  SDMMC host controller is in open drain mode during the voltage
  change and so shouldn't be drawing much current.

In order to keep the SDMMC host working properly (or for noise
reasons), there might also be a capacitor attached to the SDMMC IO
regulator.  This also will have the effect of slowing down transitions
of the regulator, especially under light loads.

From experimental evidence, we've seen the voltage change fail if the
card doesn't detect that the voltage fell to less than about 2.3V when
we turn on the clock.  On one device (that admittedly had a 47K CMD
pullup instead of a 10K CMD pullup) we saw that the voltage was just
about 2.3V after 5ms and thus the voltage change would sometimes fail.
Doubling the delay gave margin and made the voltage change work 100%
of the time, despite the slightly weaker CMD pull.

At the moment submitting this as an RFC patch since my problem _could_
be fixed by increasing the pull strength (or using a smaller
capacitor).  However being a little bit more lenient to strange
hardware could also be a good thing.
Signed-off-by: NDoug Anderson <dianders@chromium.org>
Acked-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

card->ext_csd.enhanced_area_offset is defined as "unsigned long long",
and, ext_csd[] is defined as u8.
unsigned long long data might have strange data if first bit of ext_csd[]
was 1. this patch cast it to (unsigned long long)
Special thanks to coverity <http://www.coverity.com>

ex)
        u8  data8;
        u64 data64;

        data8 = 0x80;
        data64 = (data8 << 24); // 0xffffffff80000000
        data64 = (((unsigned long long)data8) << 24); // 0x80000000;
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Allow to specify in the device-tree that no physical write-protect signal
is connected to a particular instance of a MMC controller. Setting the
property will cause the core will assume that the SD card is always
read-write.

The name for the new property is 'disable-wp' and was chosen based on the
property with the same function from the Synopsys designware mobile storage
host controller DT bindings specification.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

It is not uncommon to see systems where there is no physical write-protect
signal (e.g. when using eMMC or microSD card slots). For some controllers,
which have a dedicated write-protection detection logic (like SDHCI
controllers), the get_ro() callback can return bogus data in such a case.

Instead of handling this on a per controller basis this patch adds a new
capability flag to the MMC core that can be set to specify that the result
of get_ro() is invalid. When the flag is set the core will not call
get_ro() and assume that the card is always read-write.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Check the error code for EOPNOTSUPP and do not print
reset warning in that case.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

CRC errors could possibly be alleviated by
re-tuning so flag re-tuning needed in those cases.
Note this has no effect if re-tuning has not been
enabled.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

HS400 re-tuning must be done in HS200 mode. Add
the ability to switch from HS400 mode to HS200
mode before re-tuning and switch back to HS400
after re-tuning.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Make a separate function to do the mmc_switch status check
so it can be re-used. This is preparation for adding support
for HS400 re-tuning.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The sleep command is issued after deselecting the
card, but re-tuning won't work on a deselected card
so re-tuning must be held.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Hold re-tuning during bkops to prevent
it from conflicting with the busy state.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>