Commit Graph

432 Commits

Author SHA1 Message Date
Masahiro Yamada c7836d1593 mmc: use empty initializer list to zero-clear structures
In the MMC subsystem, we see such initializers that only clears the
first member explicitly.

For example,

  struct mmc_request mrq = {NULL};

sets the first member (.sbc) to NULL explicitly.  However, this is
an unstable form because we may insert a non-pointer member at the
top of the struct mmc_request in the future. (if we do so, the
compiler will spit warnings.)

So, using a designated initializer is preferred coding style.  The
expression above is equivalent to:

  struct mmc_request mrq = { .sbc = NULL };

Of course, this does not express our intention.  We want to fill
all struct members with zeros.  Please note struct members are
implicitly zero-cleared unless otherwise specified in the initializer.

After all, the most reasonable (and stable) form is:

  struct mmc_request mrq = {};

Do likewise for mmc_command, mmc_data as well.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-02-13 13:19:54 +01:00
Gabriel Krisman Bertazi 161e6d44a5 mmc: sdhci: Ignore unexpected CARD_INT interrupts
One of our kernelCI boxes hanged at boot because a faulty eSDHC device
was triggering spurious CARD_INT interrupts for SD cards, causing CMD52
reads, which are not allowed for SD devices.  This adds a sanity check
to the interruption path, preventing that illegal command from getting
sent if the CARD_INT interruption should be disabled.

This quirk allows that particular machine to resume boot despite the
faulty hardware, instead of getting hung dealing with thousands of
mishandled interrupts.

Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Cc: <stable@vger.kernel.org>
2017-01-31 11:26:49 +01:00
Adrian Hunter 84ec048ba1 mmc: sdhci: Fix to handle MMC_POWER_UNDEFINED
Since commit c2c24819b2 ("mmc: core: Don't power off the card when
starting the host"), the power state can still be MMC_POWER_UNDEFINED after
mmc_start_host() is called. That can trigger a warning in SDHCI during
runtime resume as it tries to restore the I/O state. Handle
MMC_POWER_UNDEFINED simply by not updating the I/O state in that case.

Fixes: c2c24819b2 ("mmc: core: Don't power off the card when starting the host")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-20 11:42:33 +01:00
Masahiro Yamada 85a882c2e9 mmc: sdhci: export sdhci_execute_tuning()
Some SDHCI-compat controllers support not only SD, but also eMMC,
but they use different commands for tuning: CMD19 for SD, CMD21 for
eMMC.

Due to the difference of the underlying mechanism, some controllers
(at least, the Cadence IP is the case) provide their own registers
for the eMMC tuning.

This commit will be useful when we want to override .execute_tuning
callback (for eMMC HS200 tuning), but still let it fall back to
sdhci_execute_tuning() for SD timing.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-08 15:02:45 +01:00
Adrian Hunter 6b11e70bb7 mmc: sdhci: Tidy tuning loop
Tidy the tuning loop by moving it to a separate function and making it a
for-loop.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:16:24 +01:00
Adrian Hunter 85336109c0 mmc: sdhci: Simplify tuning block size logic
There are only 2 possible block sizes, so simplify 2 if-statements into 1.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:16:24 +01:00
Adrian Hunter da4bc4f285 mmc: sdhci: Factor out tuning helper functions
Factor out some functions to tidy up the code in sdhci_execute_tuning.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:16:23 +01:00
Adrian Hunter d0c3ab5910 mmc: sdhci: Use mmc_abort_tuning()
Use mmc_abort_tuning() instead of open-coding the stop command.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:16:23 +01:00
Adrian Hunter 0760c35552 mmc: sdhci: Always allow tuning to fall back to fixed sampling
SDHCI falls back to fixed sampling if there is an error during tuning.
However it also reports an error unless there is periodic re-tuning.
That is not the best option because:
a) there is a reasonable chance that fixed sampling will work, especially
at room temperature.
b) re-tuning will be done again anyway if there are CRC errors.
Change to return no error always when falling back to fixed sampling.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:16:21 +01:00
Adrian Hunter 5ef5203b95 mmc: sdhci: Fix tuning reset after exhausting the maximum number of loops
If the driver has exhausted the maximum number of tuning loops, then fixed
sampling is used. To do that both SDHCI_CTRL_TUNED_CLK and
SDHCI_CTRL_EXEC_TUNING must be reset to 0, but only SDHCI_CTRL_TUNED_CLK
was being reset. Reset SDHCI_CTRL_EXEC_TUNING to 0 also.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:16:21 +01:00
Adrian Hunter 61e53bd004 mmc: sdhci: Fix recovery from tuning timeout
Clearing the tuning bits should reset the tuning circuit. However there is
more to do. Reset the command and data lines for good measure, and then
for eMMC ensure the card is not still trying to process a tuning command by
sending a stop command.

Note the JEDEC eMMC specification says the stop command (CMD12) can be used
to stop a tuning command (CMD21) whereas the SD specification is silent on
the subject with respect to the SD tuning command (CMD19). Considering that
CMD12 is not a valid SDIO command, the stop command is sent only when the
tuning command is CMD21 i.e. for eMMC. That addresses cases seen so far
which have been on eMMC.

Note that this replaces the commit fe5fb2e3b5 ("mmc: sdhci: Reset cmd and
data circuits after tuning failure") which is being reverted for v4.9+.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Dan O'Donovan <dan@emutex.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:16:20 +01:00
Adrian Hunter 2ca71c27ee Revert "mmc: sdhci: Reset cmd and data circuits after tuning failure"
This reverts commit fe5fb2e3b5 ("mmc: sdhci: Reset cmd and data circuits
after tuning failure").

A better fix is available, and it will be applied to older stable releases,
so get this out of the way by reverting it.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-12-05 14:16:20 +01:00
Linus Walleij d3c6aac3bd mmc: delete is_first_req parameter from pre-request callback
The void (*pre_req) callback in the struct mmc_host_ops vtable
is passing an argument "is_first_req" indicating whether this is
the first request or not.

None of the in-kernel users use this parameter: instead, since
they all just do variants of dma_map* they use the DMA cookie
to indicate whether a pre* callback has already been done for
a request when they decide how to handle it.

Delete the parameter from the callback and all users, as it is
just pointless cruft.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-11-29 09:05:27 +01:00
Ritesh Harjani fec7967397 mmc: sdhci: Factor out sdhci_enable_clk
Factor out sdhci_enable_clk from sdhci_set_clock
and make it EXPORT_SYMBOL so that it can be called.

Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-11-29 09:05:15 +01:00
Zach Brown 92e0c44b92 mmc: sdhci: Use sdhci-caps-mask and sdhci-caps to change the caps read during __sdhci_read_caps
The sdhci capabilities register can be incorrect. The sdhci-caps-mask
and sdhci-caps dt properties specify which bits of the register are
incorrect and what their values should be. This patch makes the sdhci
driver use those properties to correct the caps during
__sdhci_read_caps.

During __sdhci_read_caps
Use the sdhci-caps-mask property to turn off the incorrect bits of the
sdhci register after reading them.
Use the sdhci-caps to turn on bits after using sdhci-caps-mask to turn
off the incorrect ones.

Signed-off-by: Zach Brown <zach.brown@ni.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-11-29 09:00:48 +01:00
Jaehoon Chung 273c5414e3 mmc: sdhci: put together into one condition checking
value of ios->timing is not related with SDCHI v3.0.  If Controller version
is v3.0, SDHCI_QUIRK_NO_HISPD_BIT is meaningless.  To prevent the setting
wrong bit moves into one condition checking.  (e.g sdhci-s3c doesn't use
SDHCI_CTRL_HISPD bit, instead using this bit as other purpose.)

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-11-29 09:00:27 +01:00
Adrian Hunter 086b0ddbef mmc: sdhci: Fix missing enhanced strobe setting during runtime resume
Restore enhanced strobe setting during runtime resume.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-11-07 13:26:43 +01:00
Adrian Hunter fe5fb2e3b5 mmc: sdhci: Reset cmd and data circuits after tuning failure
To prevent subsequent commands failing, ensure the cmd and data circuits
are reset after a tuning timeout.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-11-07 13:26:43 +01:00
Adrian Hunter 69b962a65a mmc: sdhci: Fix unexpected data interrupt handling
In the busy response case (i.e. !host->data), an unexpected data interrupt
would result in clearing the data command as though it had completed but
without informing the upper layers and thus resulting in a hang.  Fix by
only clearing the data command for data interrupts that are expected.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-11-07 13:26:42 +01:00
Adrian Hunter 6ebebeab51 mmc: sdhci: Fix CMD line reset interfering with ongoing data transfer
CMD line reset during an ongoing data transfer can cause the data transfer
to hang.  Fix by delaying the reset until the data transfer is finished.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-11-07 13:26:42 +01:00
Haibo Chen 02265cd603 mmc: sdhci: cast unsigned int to unsigned long long to avoid unexpeted error
Potentially overflowing expression 1000000 * data->timeout_clks with
type unsigned int is evaluated using 32-bit arithmetic, and then used
in a context that expects an expression of type unsigned long long.

To avoid overflow, cast 1000000U to type unsigned long long.
Special thanks to Coverity.

Fixes: 7f05538af7 ("mmc: sdhci: fix data timeout (part 2)")
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Cc: stable@vger.kernel.org # v3.15+
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-10-17 15:16:20 +02:00
Adrian Hunter 606d313124 mmc: sdhci: Rename sdhci_set_power() to sdhci_set_power_noreg()
Unlike other cases, sdhci_set_power() does not reflect the default
implementation of the ->set_power() callback. Rename it and create
sdhci_set_power() that is the default implementation.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-10-10 14:20:41 +02:00
Adrian Hunter fc605f1d80 mmc: sdhci: Fix SDHCI_QUIRK2_STOP_WITH_TC
Multi-block data transfers can specify the number of blocks either using a
Set Block Count command (CMD23) or by sending a STOP command (CMD12) after
the required number of blocks has transferred. CMD23 is preferred, but some
cards don't support it. CMD12 with R1b response is used for writes, and
R1 response for reads.

Some SDHCI host controllers give a Transfer Complete (TC) interrupt for the
STOP command (CMD12) whether or not a R1b response has been specified. The
quirk SDHCI_QUIRK2_STOP_WITH_TC identifies those host controllers, but the
implementation only considers the case where the TC interrupt arrives at
the same time as the Command Complete (CC) interrupt. However,
occasionally TC arrives before CC. That is harmless, but does generate an
error message "Got data interrupt 0x00000002 even though no data operation
was in progress".

A simpler approach is to force R1b response onto all STOP commands, because
SDHCI will handle TC before CC in the general case, so do that.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-10-10 14:20:34 +02:00
Adrian Hunter 20845beff7 mmc: sdhci: Support cap_cmd_during_tfr requests
Now SDHCI supports commands during transfer, enable support for the core
API.

There are 3 small changes needed:

First, auto-CMD12 cannot be used with a cap_cmd_during_tfr request because
the host controller cannot expect the command line to be available.

Secondly, a cap_cmd_during_tfr request must not send a stop command, again
because the host controller cannot expect the command line to be available.

Thirdly, when a cap_cmd_during_tfr command completes, use
mmc_command_complete() to notify the upper layers that the command line is
now available for further commands.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-09-26 21:31:29 +02:00
Christopher Freeman 622b5f35da mmc: sdhci: Do not allow tuning procedure to be interrupted
wait_event_interruptible_timeout() will return early if the blocked
process receives a signal, causing the driver to abort the tuning
procedure and possibly leaving the controller in a bad state.  Since the
tuning command is expected to complete quickly (<50ms) and we've set a
timeout, use wait_event_timeout() instead.

Signed-off-by: Christopher Freeman <cfreeman@nvidia.com>
Tested-by: Robert Foss <robert.foss@collabora.com>
Signed-off-by: Robert Foss <robert.foss@collabora.com>
Reviewed-by: Benson Leung <bleung@chromium.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-09-26 21:31:11 +02:00
Jon Hunter efba142bcd mmc: sdhci: Request regulators before reading capabilities
The capabilities of the SDHCI host controller are read early during the
SDHCI host initialisation in sdhci_setup_host() and before any
regulators for the host have been requested. This means that if the host
supports some high-speed modes (according to its capabilities register),
but the board cannot because the appropriate voltage regulator is not
available, then the host cannot easily override the capabilities that
are supported.

To allow a SDHCI host controller to determine if it can support UHS high
speed modes via the presence of the MMC regulators, request the
regulators before reading the capabilities of the host controller. This
will allow the SDHCI host to use the 'reset' callback to take the
appropriate action (set flags, configure registers, etc) before the
capabilities register(s) are read.

Please note that some SDHCI hosts, such as the Tegra SDHCI host, has
the ability to mask bits in the capabilities register to prevent
certain capabilities from being advertised.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:35:00 +02:00
Dong Aisheng f37b20ebc4 mmc: sdhci: add standard hw auto retuning support
If HW supports SDHCI_TUNING_MODE_3 which is auto retuning, we won't
retune during runtime suspend and resume, instead we use Re-tuning
Request signaled via SDHCI_INT_RETUNE interrupt to do retuning and
hw auto retuning during data transfer to guarantee the signal sample
window correction.

This can avoid a mass of repeatedly retuning during small file system
data access and improve the performance.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:55 +02:00
Dong Aisheng 761daa36e2 mmc: sdhci: using common mmc_regulator_set_vqmmc()
Switch to use the more robust common mmc_regulator_set_vqmmc()
function in MMC core which set the target voltage as close as
possible to target voltage.

We did not re-factor the whole sdhci_start_signal_voltage_switch()
cause we want to keep the original signal switch order between host
and card to avoid potential break.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:52 +02:00
Adrian Hunter 07c161bcd7 mmc: sdhci: sdhci_execute_tuning() must delete timer
sdhci_send_command() starts a timer to catch cases where the host
controller fails. The timer is normally deleted when the request completes,
but in the case of sdhci_execute_tuning() the request is handled
differently and the timer is left running. This goes unnoticed because
tuning is done before another command so the timer gets reset then.
That should not be relied upon, so make sdhci_execute_tuning() delete the
timer.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:45 +02:00
Adrian Hunter 8842fd17b6 mmc: sdhci: Avoid STOP cmd triggering warning in sdhci_send_command()
The STOP command is sent in error conditions, even when the command is
not finished. Avoid triggering the warning for that in sdhci_send_command()
by setting host->cmd to NULL first.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:45 +02:00
Adrian Hunter 33a57adb6b mmc: sdhci: Do not reset cmd or data circuits that are in use
In order to support commands during data transfer, it will be possible to
need to reset the command circuit while the data circuit is in use, and
vice versa. It is now easy to determine whether the command or data circuit
is in use, and so just skip the corresponding reset if it is.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:44 +02:00
Adrian Hunter 0293d50110 mmc: sdhci: Factor out sdhci_auto_cmd12()
Factor out sdhci_auto_cmd12() so that there is a single place that controls
whether auto-CMD12 is used.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:44 +02:00
Adrian Hunter 4e9f8fe5f2 mmc: sdhci: Allow for finishing multiple requests
In order to support commands during data transfer, there will have to be up
to two active requests (mrqs) at a time, instead of just one. That means
recording which request is finished.  Doing that obsoletes host->mrq which
is therefore removed.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:43 +02:00
Adrian Hunter d7422fb489 mmc: sdhci: Separate timer timeout for command and data requests
In order to support commands during data transfer, there will have to be up
to two active requests (mrqs) at a time, instead of just one. Provide two
timers instead of just one. One of the timers is for requests that do not
use the data lines, and the other one is for requests that do.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:43 +02:00
Adrian Hunter 56a590dcdc mmc: sdhci: Factor out sdhci_data_line_cmd()
Factor out sdhci_data_line_cmd() to improve readability and because it is
used in multiple places.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:42 +02:00
Adrian Hunter 5d0d11c51a mmc: sdhci: Ensure all requests get errored out
In order to support commands during data transfer, there will have to be up
to two active requests (mrqs) at a time, instead of just one. That means
ensuring that all requests get errored out in the cases of card or driver
removal.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:42 +02:00
Adrian Hunter 5a8a3fef26 mmc: sdhci: Clear pointers when a request finishes
Several pointers are used to identify when interrupts are expected. Namely,
host->cmd, host->data_cmd and host->data. Ensure those are cleared when
a request finishes. That tidies the case when a request is errored out
before normal processing has completed, ensuring any interrupts that occur
subsequently are not acted upon.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:41 +02:00
Adrian Hunter ed1563de0b mmc: sdhci: Track whether a reset is pending
SDHCI recovers from errors by resetting the cmd and data circuits. Until
that is done, there very well might be more interrupts, so ignore them in
that case.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:41 +02:00
Adrian Hunter 0cc563ce54 mmc: sdhci: Factor out sdhci_needs_reset()
Factor out sdhci_needs_reset() so it can be reused.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:40 +02:00
Adrian Hunter a6d3bdd527 mmc: sdhci: Factor out sdhci_finish_mrq()
In order to support commands during data transfer, there will have to be up
to two active requests (mrqs) at a time, instead of just one. That means
the driver must identify which one to finish. Prepare for that by factoring
out sdhci_finish_mrq().

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:40 +02:00
Adrian Hunter 43dea098bb mmc: sdhci: Move host->data warning
In order to support commands during data transfer, it will be possible
that host->data is not NULL when preparing a new request. Move a warning
that assumes otherwise.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:39 +02:00
Adrian Hunter a4c73aba04 mmc: sdhci: Reduce the use of host->mrq
In order to support commands during data transfer, there will have to be up
to two active requests (mrqs) at a time, instead of just one. That means
host->mrq will not be able to be used.

In several places, host->mrq is used when instead the mrq can be determined
from the cmd or data pointers. Reduce the use of host->mrq by doing that.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:39 +02:00
Adrian Hunter ea96802384 mmc: sdhci: Get rid of host->busy_handle
Now that there is host->data_cmd to record the command for which a data
interrupt is expected, it is possible to determine whether a command with
busy signaling has completed without an extra flag. So host->busy_handle
is not needed. Remove it.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:38 +02:00
Adrian Hunter 7c89a3d908 mmc: sdhci: Record what command is using the data lines
In order to support commands during data transfer, there must be a
distinction between the command that is using the command line (and
for which a command interrupt is expected) and the command that is
using the data lines (for which a data interrupt is expected).

There is host->cmd for the command line, but there is only host->data
for the data lines, which is a different structure, does not represent
the command in use, and is anyway NULL in the case of commands that use
the data lines for busy signalling instead of data transfer.

Introduce host->data_cmd to record what command is using the data lines,
and use that instead of host->cmd when referring to the data command.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:38 +02:00
Adrian Hunter e0a5640a99 mmc: sdhci: Simplify sdhci_finish_command() by clearing host->cmd at the start
sdhci_finish_command() is going to set host->cmd to NULL. Simplify the
code by using a local variable to hold host->cmd and set host->cmd to
NULL at the start.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:37 +02:00
Adrian Hunter 64ed8dd46b mmc: sdhci: Get rid of redundant BUG_ONs
BUG is never the right thing for SDHCI to do. Get rid of BUG_ON in cases it
will oops anyway if the pointer is NULL, or if the condition is logically
impossible.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:37 +02:00
Adrian Hunter 6bde868181 mmc: sdhci: Move busy signal handling into sdhci_finish_cmd()
In order to support commands during data transfer, command and data
handling needs to be untangled.

That means sdhci_finish_cmd() must not be called from the data IRQ
handler. It is being called because of busy signal handling, which
is treating the command as not finished until the busy signal is
released.

Instead, move busy signal handling from sdhci_cmd_irq() into
sdhci_finish_cmd(). Then the data IRQ handler does not need to call
sdhci_finish_cmd() and can instead finish the request.

What this means in practice for a command with busy signaling, is that
the command response is read from the host controller when the command
complete interrupt is received, thus freeing up the command circuit for
other commands.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:36 +02:00
Adrian Hunter 6132a3bf07 mmc: sdhci: Add sdhci_read_caps()
Add sdhci_read_caps() and __sdhci_read_caps() to make it easier for drivers
to fix the version and capabilities registers.

Pedantically, the SDHCI specification states that the capabilities
registers are valid when the host controller resets the Software Reset For
All bit. That requirement has always been satisfied by performing a reset
at the start of initialization, and consequently that is now part of the
new functions.

Although the SDHCI_QUIRK_MISSING_CAPS quirk has not yet been removed,
drivers that want to provide their own caps can now use these functions
instead of that quirk.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:35 +02:00
Adrian Hunter 28da35899e mmc: sdhci: Tidy caps variables in sdhci_setup_host()
In preparation for adding a function to read the capability registers.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:34 +02:00
Adrian Hunter 8cb851a4da mmc: sdhci: Make signal voltage support explicit
Signal voltage support is not a quirk, it is a capability. According to the
SDHCI specification, support for 1.8V signaling is determined by the
presence of one of the capability bits SDHCI_SUPPORT_SDR50,
SDHCI_SUPPORT_SDR104, or SDHCI_SUPPORT_DDR50. This is complicated by also
supporting eMMC which has 1.8V modes and 1.2V modes. It would be possible
to use the transfer mode to determine signal voltage support, except for
eMMC DDR52 mode which uses the same capability (MMC_CAP_1_8V_DDR) for 1.8V
signaling and 3V signaling.

In addition, the mmc core will fail over from one signaling voltage to the
next (refer mmc_power_up()) which means SDHCI really needs to validate
which voltages are actually supported.

Introduce SDHCI flags for signal voltage support and set them based on the
supported transfer modes. In general, drivers should prefer to set the
supported transfer modes correctly rather than change the signal voltage
capability, except in the case where 3V DDR52 is supported but 1.8V is
not.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-07-25 10:34:34 +02:00