Commit Graph

8 Commits

Author SHA1 Message Date
Pierre Ossman
bd76631261 mmc: remove old card states
Remove card states that no longer make any sense.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-05-01 16:11:57 +02:00
Pierre Ossman
6abaa0c9fe mmc: support unsafe resume of cards
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: Pierre Ossman <drzeus@drzeus.cx>
2007-05-01 16:00:02 +02:00
Pierre Ossman
89a73cf52b mmc: separate out reading EXT_CSD
Separate the reading and decoding of the EXT_CSD register with the
actions taken on it.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-05-01 15:08:30 +02:00
Pierre Ossman
1addfcdbe4 mmc: break apart switch function
Break apart the SD switch function into one that reads the capabilities
and one that acts on them.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-05-01 14:46:08 +02:00
Philip Langdale
55556da012 MMC: Fix handling of low-voltage cards
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: Philip Langdale <philipl@overt.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-05-01 14:14:50 +02:00
Pierre Ossman
7ea239d9e6 mmc: add bus handler
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: Pierre Ossman <drzeus@drzeus.cx>
2007-05-01 13:41:06 +02:00
Pierre Ossman
da7fbe58d2 mmc: Separate out protocol ops
Move protocol operations and definitions into their own files
in an effort to separate protocol handling and bus
arbitration more clearly.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-05-01 13:04:18 +02:00
Pierre Ossman
aaac1b470b mmc: Move core functions to subdir
Create a "core" subdirectory to house the central bus handling
functions.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-05-01 13:04:18 +02:00