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: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

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

Retry errored data requests when re-tuning is needed and
add a flag to struct mmc_blk_request so that the retry
is only done once.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

If re-tuning is needed, do it in the recovery path to
give recovery commands a better chance of success.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf 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: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Make use of mmc core support for re-tuning instead
of doing it all in the sdhci driver.

This patch also changes to flag the need for re-tuning
always after runtime suspend when tuning has been used
at initialization. Previously it was only done if
the re-tuning timer was in use.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf 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: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf 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: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf 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: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

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

Hold re-tuning during erase commands to prevent
it from conflicting with the sequence of commands.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Hold re-tuning during switch commands to prevent
it from conflicting with the busy state or the CMD13
verification.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

At the start of each request, re-tune if needed and
then hold off re-tuning again until the request is done.

Note that though there is one function that starts
requests (mmc_start_request) there are two that wait for
the request to be done (mmc_wait_for_req_done and
mmc_wait_for_data_req_done).  Also note that
mmc_wait_for_data_req_done can return even when the
request is not done (which allows the block driver
to prepare a newly arrived request while still
waiting for the previous request).

This patch ensures re-tuning is held for the duration
of a request.  Subsequent patches will also hold
re-tuning at other times when it might cause a
conflict.

In addition, possibly a command is failing because
re-tuning is needed. Use mmc_retune_recheck() to check
re-tuning. At that point re-tuning is held, at least by
the request, so mmc_retune_recheck() flags host->retune_now
if the hold count is 1.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Enable re-tuning when tuning is executed and
disable re-tuning when card is no longer initialized.

In the case of SDIO suspend, the card can keep power.
In that case, re-tuning need not be disabled, but, if
a re-tuning timer is being used, ensure it is disabled
and assume that re-tuning will be needed upon resume
since it is not known how long the suspend will last.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Currently, there is core support for tuning during
initialization. There can also be a need to re-tune
periodically (e.g. sdhci) or to re-tune after the
host controller is powered off (e.g. after PM
runtime suspend / resume) or to re-tune in response
to CRC errors.

The main requirements for re-tuning are:
  - ability to enable / disable re-tuning
  - ability to flag that re-tuning is needed
  - ability to re-tune before any request
  - ability to hold off re-tuning if the card is busy
  - ability to hold off re-tuning if re-tuning is in
  progress
  - ability to run a re-tuning timer

To support those requirements 7 members are added to struct
mmc_host:

  unsigned int		can_retune:1;	/* re-tuning can be used */
  unsigned int		doing_retune:1;	/* re-tuning in progress */
  unsigned int		retune_now:1;   /* do re-tuning at next req */
  int			need_retune;	/* re-tuning is needed */
  int			hold_retune;	/* hold off re-tuning */
  unsigned int		retune_period;  /* re-tuning period in secs */
  struct timer_list	retune_timer;	/* for periodic re-tuning */

need_retune is an integer so it can be set without needing
synchronization. hold_retune is a integer to allow nesting.

Various simple functions are provided to set / clear those
variables.

Subsequent patches take those functions into use.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

This eliminates having an #ifdef returning NULL for the case
when OF is disabled.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

This patch adds the quirks and compatible string in sdhci-of-arasan.c
to support sdhci-arasan4.9a version of controller.
Signed-off-by: Suman Tripathi <stripathi@apm.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

chips have some issues for version and capbility registers, here we fake
them.
Signed-off-by: Weijun Yang <Weijun.Yang@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

hardware has 16bit to record the tuning count, so fix it to 16384.
at the same time, tuned_phases[SIRF_TUNING_COUNT] is useless as the
array is never used, so move it to a variant.
Signed-off-by: Weijun Yang <Weijun.Yang@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Ian no longer works for Codethink so the current address doesn't work.
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Clean up resource allocation and freeing.
Signed-off-by: Ian Molton <ian.molton@codethink.co.uk>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Signed-off-by: Ian Molton <ian.molton@codethink.co.uk>
[bwh: Forward-ported to 4.0]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Signed-off-by: Ian Molton <ian.molton@codethink.co.uk>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

sdhci_alloc_host() takes priv_size rather than
sizeof(struct sdhci_host) + priv_size.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Make local functions static.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

For PowerPC esdhc pre divider starts at 1, fixing the increases
the actual clock from 40KHz to 50 KHz.
Signed-off-by: Joakim Tjernlund <joakim.tjernlund@transmode.se>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

My Pengutronix address is not valid anymore, redirect people to the Pengutronix
kernel team.
Reported-by: Harald Geyer <harald@ccbib.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Current sh_mmcif_clk_update() is called from probe() and set_ios(),
but, the purpose of later one is just clk_prepare_enable().
No need to setup mmc->f_max/f_min in many times.
This patch separe sh_mmcif_clk_update() into clk_prepare_enable()
and mmc->f_max/f_min setup.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Keita Kobayashi <keita.kobayashi.ym@renesas.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

struct sh_mmcif_host has 1) int clk, 2) struct clock *hclk,
and host->clk = clk_get_rate(host->hclk).
This int clk is not necessary. Let's remove it.
And, current hclk is confusable naming. Let's rename it to clk.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Keita Kobayashi <keita.kobayashi.ym@renesas.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Keita Kobayashi <keita.kobayashi.ym@renesas.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Keita Kobayashi <keita.kobayashi.ym@renesas.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Some drivers schedule automatic hw resets. An example is mwifiex,
which schedules a card reset if the command handler between driver
and card firmware becomes out of sync
Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>