There are several situations when dw_mci_submit_data_dma() decides to
fall back to PIO mode instead of using DMA, due to a short (to avoid
overhead) or "complex" (e.g. with unaligned buffers) transaction, even
though host->use_dma is set. However dw_mci_stop_dma() decides whether
to stop DMA or set the EVENT_XFER_COMPLETE event based on host->use_dma.
When falling back to PIO mode this results in data timeout errors
getting missed and the driver locking up.

Therefore add host->using_dma to indicate whether the current
transaction is using dma or not, and adjust dw_mci_stop_dma() to use
that instead.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Tested-by: NJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Update functions for PIO pushing and pulling data to and from the FIFO
so that they can handle unaligned output buffers and unaligned buffer
lengths. This makes more of the tests in mmc_test pass.

Unaligned lengths in pulls are handled by reading the full FIFO item,
and storing the remaining bytes in a small internal buffer (part_buf).
The next data pull will copy data out of this buffer first before
accessing the FIFO again. Similarly, for pushes the final bytes that
don't fill a FIFO item are stored in the part_buf (or sent anyway if
it's the last transfer), and then the part_buf is included at the
beginning of the next buffer pushed.

Unaligned buffers in pulls are handled specially if the architecture
cannot do efficient unaligned accesses, by reading FIFO items into a
aligned local buffer, and memcpy'ing them into the output buffer, again
storing any remaining bytes in the internal buffer. Similarly for pushes
the buffer is memcpy'd into an aligned local buffer then written to the
FIFO.
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>

The FIFO_DEPTH hardware configuration parameter can be found from the
power-on value of RX_WMark in the FIFOTH register. This is used to
initialise the watermarks, but when calculating the number of free fifo
spaces a preprocessor definition is used which is hard coded to 32.

Fix reading the value out of FIFOTH (the default value in the RX_WMark
field is FIFO_DEPTH-1 not FIFO_DEPTH). Allow the fifo depth to be
overriden by platform data (since a bootloader may have changed FIFOTH
making auto-detection unreliable). Store the fifo_depth for later use.
Also fix the calculation to find the number of free bytes in the fifo to
include the fifo depth in the left shift by the data shift, since the
fifo depth is measured in fifo items not bytes.
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>

Convert the card insert/remove tasklet to a workqueue, and call the
setpower platform specific callback without the spinlock held. This
means neither of the setpower or get_cd callbacks are called from atomic
context which allows them to sleep.
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>

When a request is made, the card presence is checked and the request is
queued. These two parts must be atomic with respect to card removal, or
a card removal could be handled in between, and the new request wouldn't
get cancelled until another card was inserted. Therefore move the
spinlock protection from dw_mci_queue_request() up into dw_mci_request()
to cover the presence check.

Note that the test_bit() used for the presence check isn't atomic
itself, so should have been protected by a spinlock anyway.
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>

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>