linux-toradex.git/drivers/mmc/core/sd.c, branch v5.0

mmc: core: Rename ->reset() bus ops to ->hw_reset()

2018-05-08T07:33:29+00:00

The bus ops ->reset() executes a full HW reset of the card, as the calling
function mmc_hw_reset() also indicates by its name. Let's convert to follow
the similar names, for both the bus ops callback and for the corresponding
bus ops functions, as to clarify the purpose of code.

Signed-off-by: Ulf Hansson 
Tested-by: Quentin Schulz 
Reviewed-by: Shawn Lin

mmc: core: Add capability to avoid 3.3V signaling

2018-05-02T13:08:44+00:00

Some SD host controllers cannot handle extended use of 3.3V signaling.
To accommodate these controllers, add a capability that requires us to
negotiate the voltage down from 3.3V during card initialization.

Signed-off-by: Kyle Roeschley 
Signed-off-by: Jennifer Dahm 
Signed-off-by: Ulf Hansson

mmc: core: Export card RCA register via sysfs

2018-03-15T13:43:05+00:00

This patch exports RCA register to sysfs which will help in reading the
disk identification information.

Reviewed-by: Shawn Lin 
Signed-off-by: Harish Jenny K N 
Signed-off-by: Ulf Hansson

mmc: sd: Remove redundant err assignment from mmc_read_switch

2018-03-15T08:32:30+00:00

Variable err would be firstly initialized by the return value of
mmc_sd_switch().

Signed-off-by: Shawn Lin 
Signed-off-by: Ulf Hansson

mmc: core: Don't try UHS-I mode if 4-bit mode isn't supported

2018-03-15T08:30:39+00:00

Per SD specification physical layer v4.0, section 3.9.4, it
says "UHS-I supports only 4-bit mode. Host shall select 4-bit
mode by ACMD6. However mmc_sd_init_uhs_card() still go ahead
to initialize the cards anyway, whether card or host won't
support 4-bit mode.

  This breaks the platforms which could support UHS-I mode but on
some certain boards only support 1-bit mode with a UHS-I card inserted,
as all the tuning process is broken due to this. Alternatively, we
should check the return value from mmc_set_bus_width() to see if host
could finish the request to switch the bus width on its side. But that
needs more thing to do than this patch that just bails out early to try
high speed mode if 4-bit mode isn't available for whatever reason. And
this patch could also fix the same problem for sdio since R4_18V_PRESENT
won't be set for ocr when mmc_sdio_init_card() finds mmc_host_uhs()
is false.

  Note that this patch doesn't keep the checking of card->scr.sda_spec3
and comparing card->scr.bus_widths with SD_SCR_BUS_WIDTH_4 within
mmc_sd_init_uhs_card() since if the sd cards response with SD_ROCR_S18A,
it definitely supports UHS-I mode, which implicitly means these checkings
are always true.

Signed-off-by: Shawn Lin 
Signed-off-by: Ulf Hansson

mmc: core: prepend 0x to OCR entry in sysfs

2017-11-29T09:46:53+00:00

The sysfs entry "ocr" was missing the 0x prefix to identify it as hex
formatted.

Fixes: 5fb06af7a33b ("mmc: core: Extend sysfs with OCR register")
Signed-off-by: Bastian Stender 
Cc:  # v4.8+
[Ulf: Amended change to also cover SD-cards]
Signed-off-by: Ulf Hansson

mmc: sd: Fix signal voltage when there is no power cycle

2017-10-30T10:45:57+00:00

Some boards have SD card connectors where the power rail cannot be switched
off by the driver. However there are various circumstances when a card
might be re-initialized, such as after system resume, warm re-boot, or
error handling. However, a UHS card will continue to use 1.8V signaling
unless it is power cycled.

If the card has not been power cycled, it may still be using 1.8V
signaling. According to the SD spec., the Bus Speed Mode (function group 1)
bits 2 to 4 are zero if the card is initialized at 3.3V signal level. Thus
they can be used to determine if the card has already switched to 1.8V
signaling. Detect that situation and try to initialize a UHS-I (1.8V)
transfer mode.

Tested with the following cards:
  Transcend 4GB High Speed
  Kingston 64GB SDR104
  Lexar by Micron HIGH-PERFORMANCE 300x 16GB DDR50
  SanDisk Ultra 8GB DDR50
  Transcend Ultimate 600x 16GB SDR104
  Transcend Premium 300x 64GB SDR104
  Lexar by Micron Professional 1000x 32GB UHS-II SDR104
  SanDisk Extreme Pro 16GB SDR104

Signed-off-by: Adrian Hunter 
Tested-by: Zhoujie Wu 
Reviewed-by: Shawn Lin 
Signed-off-by: Ulf Hansson

mmc: core: Introduce host claiming by context

2017-10-30T10:45:49+00:00

Currently the host can be claimed by a task.  Change this so that the host
can be claimed by a context that may or may not be a task.  This provides
for the host to be claimed by a block driver queue to support blk-mq, while
maintaining compatibility with the existing use of mmc_claim_host().

Signed-off-by: Adrian Hunter 
Signed-off-by: Ulf Hansson

mmc: core: correct taac parameter according to the specification

2017-08-30T12:01:46+00:00

Per the spec of JESD84-B51, section 7.3, replace tacc with taac to
fix the obvious typo.

Signed-off-by: Shawn Lin 
Signed-off-by: Ulf Hansson

mmc: core: Re-factor code for sending CID

2017-06-20T08:30:45+00:00

Instead of having the caller to check for SPI mode, let's leave that to
internals of mmc_send_cid(). In this way the code gets cleaner and it
becomes clear what is specific to SPI and non-SPI mode.

Signed-off-by: Ulf Hansson 
Reviewed-by: Linus Walleij 
Reviewed-by: Shawn Lin