Most controllers can check if there is a card in the slot.
However, they require pins that could be not available because
required by other functions and the detection of a card must
be performed in another way. This patch adds a weak function
that a board can implement to add its internal custom way
to check the presence of a MMC/SD card.
Signed-off-by: Stefano Babic <sbabic@denx.de>
Most cards do not answer if some reserved bits
in the ocr are set. However, some controllers
can set bit 7 (reserved for low voltages), but
how to manage low voltages SD card is not yet
specified.
Signed-off-by: Stefano Babic <sbabic@denx.de>
We need to switch back to 1-bit before initialization or SD 2.0 cards
will fail to send SCR if we've switched to 4-bit already.
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
SCR & switch data are read from card as big-endian words and should be
converted to CPU byte order.
Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
Cards which are not compatible with SD 2.0 standard, may return response
for CMD8 command, but it will be invalid in terms of SD 2.0. We should
accept this case as admissible, just like Linux does.
Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
The mmc code defines the response as an array of chars. However, it
access the response bytes both as (i) an array of four uints (with
casts) and (ii) as individual chars. The former case is used more
often, including by the driver when it assigns the response.
The char-wise accesses are broken on little endian systems because they
assume that the bytes in the uints are in big endian byte order.
This patch fixes this by changing the response to be an array of four
uints and replacing the char-wise accesses with equivalent uint-wise
accesses.
Signed-off-by: Rabin Vincent <rabin@rab.in>
The generic MMC core uses direct long long divisions, which do not build
with ARM EABI toolchains. Use lldiv() instead, which works everywhere.
Signed-off-by: Rabin Vincent <rabin@rab.in>
find_mmc_device returns NULL if an invalid device number is specified.
Check for this to avoid dereferencing NULL pointers.
Signed-off-by: Rabin Vincent <rabin@rab.in>
__attribute__ follows gcc's documented syntax and is generally more
common than __attribute. This change is only asthetic and should not
affect functionality.
Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Here's a new framework (based roughly off the linux one) for managing
MMC controllers. It handles all of the standard SD/MMC transactions,
leaving the host drivers to implement only what is necessary to
deal with their specific hardware.
This also hooks the infrastructure into the PowerPC board code
(similar to how the ethernet infrastructure now hooks in)
Some of this code was contributed by Dave Liu <daveliu@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>