Especially for SDIO drivers which may have special conditions/errors to
report, it is a good thing to relay the returned error code back to upper
layers.
This also allows for the rationalization of the resume path where code to
"remove" a no-longer-existing or replaced card was duplicated into the
MMC, SD and SDIO bus drivers.
In the SDIO case, if a function suspend method returns an error, then all
previously suspended functions are resumed and the error returned. An
exception is made for -ENOSYS which the core interprets as "we don't
support suspend so just kick the card out for suspend and return success".
When resuming SDIO cards, the core code only validates the manufacturer
and product IDs to make sure the same kind of card is still present before
invoking functions resume methods. It's the function driver's
responsibility to perform further tests to confirm that the actual same
card is present (same MAC address, etc.) and return an error otherwise.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some time ago, I have send a patch to the mmc_spi subsystem changing the
error codes. This was after a discussion with Pierre about using EINVAL
only for non-recoverable errors. This patch was accepted as
http://git.kernel.org/linus/fdd858db7113ca64132de390188d7ca00701013d
Unfortunately, several weeks later, I realized that this patch has opened
a little can of worms because there are SD cards on the market which
a) claim that they support the switch command
AND
b) refuse to execute this command if operating in SPI mode.
So, such a card would get unusuable in an embedded linux system in SPI
mode, because the init sequence terminates with an error.
This patch adds the missing error codes to the caller of the switch
command and restores the old behaviour to fail gracefully if these
commands can not execute.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Cc: <linux-mmc@vger.kernel.org>
Cc: <stable@kernel.org> [2.6.31.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Power can be saved by powering off cards that are not in use. This is
similar to suspend / resume except it is under the control of the driver,
and does not require any power management support. It can only be used
when the driver can monitor whether the card is removed, otherwise it is
unsafe. This is possible because, unlike suspend, the driver still
receives card detect and / or cover switch interrupts.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
eMMC's are not removable, so unsafe resume is OK always.
To permit this a new host capability MMC_CAP_NONREMOVABLE has been added
and suspend / resume updated accordingly.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Let attribute group vectors be declared "const". We'd
like to let most attribute metadata live in read-only
sections... this is a start.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some cards are not able to calculate a valid CRC16 value
for CID and CSD reads (CRC for 512 byte data blocks is OK).
By moving the CRC enable after the read of CID and CSD, these
cards can be used. This patch was tested with a faulty 8 GByte
takeMS Class 6 SDHC card. This patch was suggested by
Pierre Ossman.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>
Make the variable name in the comments match the actual name
of the variable.
Signed-off-by: Deepak Saxena <dsaxena@laptop.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Now get_ro() callback must return 0/1 values for its logical states, and
negative errno values in case of error. If particular host instance doesn't
support RO/WP switch, it should return -ENOSYS.
This patch changes some hosts in two ways:
1. Now functions should be smart to not return negative values in
"RO asserted" case (particularly gpio_ calls could return negative
values for the outermost GPIOs).
Also, board code usually passes get_ro() callbacks that directly return
gpioreg & bit result, so at91_mci, imxmmc, pxamci and mmc_spi's get_ro()
handlers need take special care when returning platform's values to the
mmc core.
2. In case of host instance didn't implement get_ro() callback, it should
really return -ENOSYS and let the mmc core decide what to do about it
(mmc core thinks the same way as the hosts, so it isn't functional
change).
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Suppressing uevents turned out to be a bad idea as it screws up the
order of events, making user space very confused. Change the system to
use sysfs groups instead.
This is a regression that, for some odd reason, has gone unnoticed for
some time. It confuses hal so that the block devices (which have the
mmc device as a parent) are not registered. End result being that
desktop magic when cards are inserted won't work.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
Replace all cases of BUG_ON with WARN_ON where there is a chance
(with varying degrees of slim) that the kernel can continue without
incidence.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Let the user know that the kernel actually detected the card
by printing some basic information in dmesg.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
When the card has been added to the device model, it might be bound
to a card driver. Therefore, we have to release the host lock when
trying to remove it as we otherwise might deadlock with the driver.
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>
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: Pierre 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: 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>
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>
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>
