kernel.git/drivers/mmc/core/sd.c, branch linux-2.6.31.y

mmc_spi: fail gracefully if host or card do not support the switch command

2009-10-05T16:31:38Z

commit d08ebeddfb3293fa4bdfca9c610daf1e8ec8b233 upstream. 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 Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

mmc_spi: do not check CID and CSD blocks with CRC16

2009-04-08T18:37:53Z

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 Signed-off-by: Pierre Ossman

MMC: Trivial comment cleanup

2008-07-15T12:14:41Z

Make the variable name in the comments match the actual name of the variable. Signed-off-by: Deepak Saxena Signed-off-by: Pierre Ossman

mmc: change .get_ro() callback semantics

2008-07-15T12:14:41Z

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 Signed-off-by: Pierre Ossman

mmc: use sysfs groups to handle conditional attributes

2008-03-23T00:02:20Z

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 Signed-off-by: Linus Torvalds

MMC core learns about SPI

2007-09-23T19:51:30Z

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 Signed-off-by: Pierre Ossman

mmc: replace BUG_ON with WARN_ON

2007-09-23T19:23:07Z

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

mmc: improve error code feedback

2007-09-23T07:14:43Z

Now that we use "normal" error codes, improve the reporting and response to error codes in the core. Signed-off-by: Pierre Ossman

mmc: remove custom error codes

2007-09-23T06:46:48Z

Convert the MMC layer to use standard error codes and not its own, incompatible values. Signed-off-by: Pierre Ossman

mmc: add missing printk levels

2007-07-26T00:05:49Z

Some printk:s were missing an explicit level. Signed-off-by: Pierre Ossman