DMA is only used for transactions exceeding a certain length, otherwise
PIO is used. The TXDR and RXDR interrupts are masked when in DMA mode
but still fire. When switching to PIO mode (e.g. to get SCR field when
an SD card is inserted) these interrupts are not cleared and so they
trigger the ISR as soon as they are unmasked. If the previous DMA did a
write, then the ISR will handle the TXDR interrupt even if the
transaction is a read, completing the transaction without modifying the
read buffer.

This is fixed primarily by clearing these two interrupts before
unmasking them when setting up PIO mode, and also by making the ISR more
robust by only handling TXDR/RXDR in the correct read/write direction.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Response timeout (RTO), Response crc error (RCRC) and Response error (RE)
signals come with command done (CD) and can be raised preceding command
done (CD). That is these error interrupts and CD can be handled in
separate dw_mci_interrupt(). If mmc_request_done() is called because of
a response timeout before command done has occured, we might send the
next request before the CD of current request is finished. This can
bring about a broken sequence of request and request-done.

And Data error interrupt (DRTO, DCRC, SBE, EBE) and data transfer
over (DTO) have the same problem.
Signed-off-by: NSeungwon Jeon <tgih.jun@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

This patch sets the card_width bit of CTYPE for the corresponding card.

CTYPE[31] and CTYPE[16] correspond respectively to card[15] and card[0]
for 8-bit mode. And CTYPE[15] and CTYPE[0] correspond respectively to
card[15] and CTYPE[0] for 1-bit or 4-bit mode.
Signed-off-by: NSeungwon Jeon <tgih.jun@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

regulator_enable() was incorrectly placed in the suspend function
instead of the resume function.
Signed-off-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

This patch uses the fixed burst bit when using an internal DMA controller.
I found increased performance with IDMAC when this bit is set.
Signed-off-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

This patch adds support for power regulators.
Signed-off-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Nkyungmin Park <kyungmin.park@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

This patch is related to re-init processing on suspend/resume.

When card is resuming, some register is reset.  If card is removable,
maybe controller should be rescan for card.  But if assume card is
non-removable, need to restore the old value at registers.

We store the value of FIFOTH at probe time and then restore it in
dw_mci_resume().
Signed-off-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

This patch adds quirks and capabilities to platdata.

Some cards don't use the CDn pin; in that case, we assume the card's
inserted. Some boards need other capabilities. So, we add capabilities
in the board's platdata.
Signed-off-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

count is only ever used by assigning to old_len if count == 0, and
then old_len isn't ever used at all.  So, both are redundant.  Fixes:

drivers/mmc/host/dw_mmc.c: In function ‘dw_mci_read_data_pio’:
drivers/mmc/host/dw_mmc.c:1034:32: warning: variable ‘old_len’ set but
not used [-Wunused-but-set-variable]
Signed-off-by: NChris Ball <cjb@laptop.org>
Acked-by: NWill Newton <will.newton@imgtec.com>

This patch adds DDR mode support to dw_mmc.

If we set any bit in UHS_REG bit[16:31], the card of that slot is
supported for DDR mode.  For example, if UHS_REG[16] is set, card
number 0 is DDR mode.
Signed-off-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

This patch adds support for 8-bit buswidth.
dw_mmc can use 8-bit buswidth and set to CTYPE_8BIT in card-type register.
Signed-off-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Setting this bit in the clock enable register will stop the clock
when the card is in the IDLE state.
Signed-off-by: NWill Newton <will.newton@imgtec.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

We need to run the card detect tasklet at the end of slot initialisation
as it is possible that a card has been inserted prior to boot, so we don't
see an insertion interrupt and now the card is sitting there inserted but
with no power to it.
Signed-off-by: NNeil Jones <neil.jones@imgtec.com>
Signed-off-by: NWill Newton <will.newton@imgtec.com>
Reviewed-by: NMatt Fleming <matt@console-pimps.org>
Signed-off-by: NChris Ball <cjb@laptop.org>

This adds the mmc host driver for the Synopsys DesignWare mmc
host controller, found in a number of embedded SoC designs.
Signed-off-by: NWill Newton <will.newton@imgtec.com>
Reviewed-by: NMatt Fleming <matt@console-pimps.org>
Reviewed-by: NChris Ball <cjb@laptop.org>
Signed-off-by: NChris Ball <cjb@laptop.org>