linux-toradex.git/drivers/mmc/core, branch v4.4.48

mmc: longer timeout for long read time quirk

2016-06-01T19:15:50+00:00

commit 32ecd320db39bcb007679ed42f283740641b81ea upstream.

008GE0 Toshiba mmc in some Intel Baytrail tablets responds to
MMC_SEND_EXT_CSD in 450-600ms.

This patch will...

() Increase the long read time quirk timeout from 300ms to 600ms. Original
   author of that quirk says 300ms was only a guess and that the number
   may need to be raised in the future.

() Add this specific MMC to the quirk

Signed-off-by: Matt Gumbel 
Signed-off-by: Adrian Hunter 
Signed-off-by: Ulf Hansson 
Signed-off-by: Greg Kroah-Hartman

mmc: mmc: Fix partition switch timeout for some eMMCs

2016-06-01T19:15:50+00:00

commit 1c447116d017a98c90f8f71c8c5a611e0aa42178 upstream.

Some eMMCs set the partition switch timeout too low.

Now typically eMMCs are considered a critical component (e.g. because
they store the root file system) and consequently are expected to be
reliable.  Thus we can neglect the use case where eMMCs can't switch
reliably and we might want a lower timeout to facilitate speedy
recovery.

Although we could employ a quirk for the cards that are affected (if
we could identify them all), as described above, there is little
benefit to having a low timeout, so instead simply set a minimum
timeout.

The minimum is set to 300ms somewhat arbitrarily - the examples that
have been seen had a timeout of 10ms but were sometimes taking 60-70ms.

Signed-off-by: Adrian Hunter 
Signed-off-by: Ulf Hansson 
Signed-off-by: Greg Kroah-Hartman

mmc: core: Enable tuning according to the actual timing

2016-03-03T23:07:15+00:00

commit e10c321977091f163eceedec0650e0ef4b3cf4bb upstream.

While in sdhci_execute_tuning() the choice whether or not to enable the
tuning is done on the actual timing, in the mmc_sdio_init_uhs_card() the
check is done on the capability of the card.

This difference is causing some issues with some SDIO cards in DDR50
mode where the CDM19 is wrongly issued.

With this patch we modify the check in both
mmc_(sd|sdio)_init_uhs_card() functions to take the proper decision
only according to the actual timing specification.

Signed-off-by: Carlo Caione 
Signed-off-by: Ulf Hansson 
Signed-off-by: Greg Kroah-Hartman

mmc: mmc: Fix incorrect use of driver strength switching HS200 and HS400

2016-03-03T23:07:15+00:00

commit adb24d42a516bca8b9741ed21206509daaab5b13 upstream.

Commit cc4f414c885c ("mmc: mmc: Add driver strength selection")
added driver strength selection for eMMC HS200 and HS400 modes.
That patch also set the driver stength when transitioning through
High Speed mode to HS200/HS400, but driver strength is not defined
for High Speed mode.  While the JEDEC specification is not clear
on this point it has been observed to cause problems for some eMMC,
and removing the driver strength setting in this case makes it
consistent with the normal use of High Speed mode.

Signed-off-by: Wenkai Du 
Signed-off-by: Adrian Hunter 
Signed-off-by: Ulf Hansson 
Signed-off-by: Greg Kroah-Hartman

mmc: sdio: Fix invalid vdd in voltage switch power cycle

2016-03-03T23:07:15+00:00

commit d9bfbb95ed598a09cf336adb0f190ee0ff802f0d upstream.

The 'ocr' parameter passed to mmc_set_signal_voltage()
defines the power-on voltage used when power cycling
after a failure to set the voltage.  However, in the
case of mmc_sdio_init_card(), the value passed has the
R4_18V_PRESENT flag set which is not valid for power-on
and results in an invalid vdd.  Fix by passing the card's
ocr value which does not have the flag.

Signed-off-by: Adrian Hunter 
Signed-off-by: Ulf Hansson 
Signed-off-by: Greg Kroah-Hartman

mmc: mmc: Improve reliability of mmc_select_hs400()

2015-11-09T12:16:32+00:00

mmc_select_hs400() calls __mmc_switch() which checks the switch is
successful using CMD13 (SEND_STATUS).  The problem is that it does that
using the timing settings of the previous mode.  That is prone to error,
especially when switching from HS to HS400 because the timing parameters
for HS mode are tighter than the timing parameters for HS400 mode.

In the case when CMD13 polling is used (i.e. not MMC_CAP_WAIT_WHILE_BUSY)
with the switch command, it must be assumed that using different modes on
the card and host must work.

However in the case when CMD13 polling is not used
(i.e. MMC_CAP_WAIT_WHILE_BUSY) mmc_select_hs400() can be made more
reliable by setting the host to the correct timing before sending CMD13.

This patch does that.

Signed-off-by: Adrian Hunter 
Cc:  # 4.2+
Tested-by: Alim Akhtar 
Signed-off-by: Ulf Hansson

mmc: mmc: Move mmc_switch_status()

2015-11-09T12:16:26+00:00

Move the mmc_switch_status() function in preparation for calling it
in mmc_select_hs400().

Signed-off-by: Adrian Hunter 
Cc:  # 4.2+
Tested-by: Alim Akhtar 
Signed-off-by: Ulf Hansson

mmc: mmc: Fix HS setting in mmc_select_hs400()

2015-11-09T12:16:20+00:00

mmc_select_hs400() begins with the card and host in HS200 mode.
Therefore, any commands sent to the card should use HS200 timing.
It is incorrect to set the host to High Speed (HS) timing before
sending the switch command.  Doing so is unreliable because
the timing parameters for HS mode are tighter than the timing
parameters for HS200 mode.  Thus the HS timings should be set
only after the card has switched mode.

However, it is not unreasonable first to reduce the frequency to
the HS mode frequency, which should make the switch command and
subsequent CMD13 commands more reliable.

This patch does that.

Signed-off-by: Adrian Hunter 
Cc:  # 4.2+
Tested-by: Alim Akhtar 
Signed-off-by: Ulf Hansson

mmc: mmc: Improve reliability of mmc_select_hs200()

2015-11-09T12:12:08+00:00

Currently mmc_select_hs200() uses __mmc_switch() which checks the
success of the switch to HS200 mode using CMD13 (SEND_STATUS).
The problem is that it does that using the timing settings of legacy
mode.  That is prone to error, not least because the timing parameters
for legacy mode are tighter than the timing parameters for HS200 mode.

In the case when CMD13 polling is used (i.e. not MMC_CAP_WAIT_WHILE_BUSY)
with the switch command, it must be assumed that using different modes on
the card and host must work.

However in the case when CMD13 polling is not used
(i.e. MMC_CAP_WAIT_WHILE_BUSY) mmc_select_hs200() can be made more
reliable by setting the host to the correct timing before sending CMD13.

This patch does that.

A complication is that the caller, mmc_select_timing(), will ignore a
switch error (indicated by -EBADMSG), assume the old mode is valid
and continue, so the old timing must be restored in that case.

Signed-off-by: Adrian Hunter 
Cc:  # 4.2+
Tested-by: Alim Akhtar 
Signed-off-by: Ulf Hansson

mmc: pwrseq: Use highest priority for eMMC restart handler

2015-10-27T10:11:06+00:00

The pwrseq_emmc driver does a eMMC card reset before a system reboot to
allow broken or limited ROM boot-loaders (that don't have an eMMC reset
logic) to be able to read the second stage from the eMMC.

But this has to be called before a system reboot handler and while most
of them use the priority 128, there are other restart handlers (such as
the syscon-reboot one) that use a higher priority. So, use the highest
priority to make sure that the eMMC hw is reset before a system reboot.

Signed-off-by: Javier Martinez Canillas 
Tested-by: Markus Reichl 
Tested-by: Anand Moon 
Reviewed-by: Alim Akhtar 
Tested-by: Douglas Anderson 
Signed-off-by: Ulf Hansson