Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Move basic host class device handling to its own file for clarity.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Move bus operations to its own file for the sake of clarity. Also
delegate sysfs attributes to bus handlers in preparation for other
more exotic types.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Somehow the code to read the read-only switch of SD cards got lost
in the reorganisation.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Make sure we don't call the switch function on cards too old to
support it. They should just ignore it, but some have been reported
to lock up instead.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Fix a broken if clause which was causing SD cards to go into
4-bit mode even if the host did not support it.

(Reported by David Brownell and Marc Pignat)
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Cc: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As mmc_detect_change() can be called from irq context, using
claim (which can sleep) is inherently unsafe. Use the host
spinlock instead, which also is faster.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Change Kconfig objects from "menu, config" into "menuconfig" so
that the user can disable the whole feature without having to
enter the menu first.
Signed-off-by: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Remove card states that no longer make any sense.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Since many have the system root on MMC/SD we must allow some foot
shooting when it comes to resume.

We cannot detect if a card is removed and reinserted during suspend,
so the safe approach would be to assume it was, avoiding potential
filesystem corruption. This will of course not work if you cannot
release the card before suspend.

This commit adds a compile time option that makes the MMC layer
assume the card wasn't touched if it is redetected upon resume.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Separate the reading and decoding of the EXT_CSD register with the
actions taken on it.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Break apart the SD switch function into one that reads the capabilities
and one that acts on them.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Fix handling of low voltage MMC cards.

The latest MMC and SD specs both agree that support for
low-voltage operations is indicated by bit 7 in the OCR.
The MMC spec states that the low voltage range is
1.65-1.95V while the SD spec leaves the actual voltage
range undefined - meaning that there is still no such
thing as a low voltage SD card.

However, an old Sandisk spec implied that bits 7.0
represented voltages below 2.0V in 1V or 0.5V increments,
and the code was accordingly written with that expectation.

This confusion meant that host drivers attempting to support
the typical low voltage (1.8V) would set the wrong bits in
the host OCR mask (usually bits 5 and/or 6) resulting in the
the low voltage mode never being used.

This change corrects the low voltage range and adds sanity
checks on the reserved bits (0-6) and for SD cards that
claim to support low-voltage operations.
Signed-off-by: NPhilip Langdale <philipl@overt.org>
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Delegate protocol handling to "bus handlers". This allows the core to
just handle the task of arbitrating the bus. Initialisation and
pampering of cards is now done by the different bus handlers.

This design also allows MMC and SD (and later SDIO) to be more cleanly
separated, allowing easier maintenance.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Move protocol operations and definitions into their own files
in an effort to separate protocol handling and bus
arbitration more clearly.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>

Create a "core" subdirectory to house the central bus handling
functions.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>