Teach the MMC/SD/SDIO core about using SPI mode.
- Use mmc_host_is_spi() so enumeration works through SPI signaling
and protocols, not just the native versions.
- Provide the SPI response type flags with each request issued,
including requests from the new lock/unlock code.
- Understand that cmd->resp[0] and mmc_get_status() results for SPI
return different values than for "native" MMC/SD protocol; this
affects resetting, checking card lock status, and some others.
- Understand that some commands act a bit differently ... notably:
* OP_COND command doesn't return the OCR
* APP_CMD status doesn't have an R1_APP_CMD analogue
Those changes required some new and updated primitives:
- Provide utilities to access two SPI-only requests, and one
request that wasn't previously needed:
* mmc_spi_read_ocr() ... SPI only
* mmc_spi_set_crc() ... SPI only (override by module parm)
* mmc_send_cid() ... for use without broadcast mode
- Updated internal routines:
* Previous mmc_send_csd() modified into mmc_send_cxd_native();
it uses native "R2" responses, which include 16 bytes of data.
* Previous mmc_send_ext_csd() becomes new mmc_send_cxd_data()
helper for command-and-data access
* Bugfix to that mmc_send_cxd_data() code: dma-to-stack is
unsafe/nonportable, so kmalloc a bounce buffer instead.
- Modified mmc_send_ext_csd() now uses mmc_send_cxd_data() helper
- Modified mmc_send_csd(), and new mmc_spi_send_cid(), routines use
those helper routines based on whether they're native or SPI
The newest categories of cards supported by the MMC stack aren't expected
to work yet with SPI: MMC or SD cards with over 4GB data, and SDIO.
All those cards support SPI mode, so eventually they should work too.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch makes the following needlessly global functions static:
- sd_ops.c: mmc_app_cmd()
- core.c: __mmc_release_bus()
- core.c: mmc_start_request()
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Pierre 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: Pierre 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: Pierre 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: Pierre 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: Pierre Ossman <drzeus@drzeus.cx>
David Brownell