linux.git/drivers/mmc/core/host.c, branch v4.1

mmc: core: Initial support for MMC power sequences

2015-01-28T11:31:12+00:00

System on chip designs may specify a specific MMC power sequence. To
successfully detect an (e)MMC/SD/SDIO card, that power sequence must
be followed while initializing the card.

To be able to handle these SOC specific power sequences, let's add a
MMC power sequence interface. It provides the following functions to
help the mmc core to deal with these power sequences.

mmc_pwrseq_alloc() - Invoked from mmc_of_parse(), to initialize data.
mmc_pwrseq_pre_power_on()- Invoked in the beginning of mmc_power_up().
mmc_pwrseq_post_power_on()- Invoked at the end in mmc_power_up().
mmc_pwrseq_power_off()- Invoked from mmc_power_off().
mmc_pwrseq_free() - Invoked from mmc_free_host(), to free data.

Each MMC power sequence provider will be responsible to implement a set
of callbacks. These callbacks mirrors the functions above.

This patch adds the skeleton, following patches will extend the core of
the MMC power sequence and add support for a specific simple MMC power
sequence.

Do note, since the mmc_pwrseq_alloc() is invoked from mmc_of_parse(),
host drivers needs to make use of this API to enable the support for
MMC power sequences. Moreover the MMC power sequence support depends on
CONFIG_OF.

Signed-off-by: Ulf Hansson 
Tested-by: Javier Martinez Canillas 
Reviewed-by: Javier Martinez Canillas

mmc: slot-gpio: Rework how to handle allocation of slot-gpio data

2015-01-19T08:56:18+00:00

By moving the allocation of the slot-gpio data into mmc_alloc_host(),
we can remove the slot-gpio internal calls to mmc_gpio_alloc().

This means mmc_gpio_alloc() has now only one caller left, which
consequence allow us to simplify and remove some of the slot-gpio code.

Additionally, this makes the slot-gpio mutex redundant, so let's remove
it.

Signed-off-by: Ulf Hansson

mmc: core: Free all resources for the class device at ->dev_release()

2015-01-19T08:56:17+00:00

To be consistent when freeing data, let's move the idr_remove() call
from mmc_free_host() into the ->dev_release() callback for the class
device.

Signed-off-by: Ulf Hansson

mmc: core: Return error at failure of request CD/WP in mmc_of_parse()

2015-01-19T08:56:14+00:00

Instead of just printing an error when mmc_of_parse() fails to request
CD/WP GPIO pins, let's propagate all errors, except for -ENOENT.
Earlier only -EPROBE_DEFER was handled correctly.

As a side effect of this change and by relying on host drivers to
handle the errors during ->probe(), we don't need to free any data in
the error path.

This also means we are actually fixing a bug, since we remove the call
to mmc_gpio_free_cd() which wasn't the correct function to invoke to
handle cleanup. Instead that should have been mmc_gpiod_free_cd().

Signed-off-by: Ulf Hansson

mmc: core: fix card detection regression

2014-11-05T08:28:48+00:00

Since commit 89168b489915 ("mmc: core: restore detect line inversion
semantics"), the SD card on i.MX28 (and possibly other) devices isn't
detected and booting stops at:

[    4.120617] Waiting for root device /dev/mmcblk0p3...

This is caused by the MMC_CAP2_CD_ACTIVE_HIGH flag being set incorrectly
when the host controller doesn't use a GPIO for card detection (but
instead uses a dedicated pin). In this case mmc_gpiod_request_cd() will
return before assigning to the gpio_invert variable, leaving the
variable uninitialized. The variable then gets used to set the flag.
This patch fixes the issue by making sure gpio_invert is set to false
when a GPIO isn't used. After this patch, i.MX28 boots fine.

The MMC_CAP2_RO_ACTIVE_HIGH (write protect) flag is also set incorrectly
for the exact same reason (it uses the same uninitialized variable), so
this patch fixes that too.

Fixes: 89168b489915 ("mmc: core: restore detect line inversion semantics")
Reported-by: Stefan Wahren 
Signed-off-by: Kristina Martšenko 
Tested-by: Fabio Estevam 
Signed-off-by: Ulf Hansson

mmc: core: restore detect line inversion semantics

2014-10-02T09:51:26+00:00

commit 98e90de99a0c43bd434da814c882c4332441871e
"mmc: host: switch OF parser to use gpio descriptors"
switched the semantic behaviour of card detect and read
only flags such that the inversion capability flag would
only be set if inversion was explicitly specified in the
device tree, in the hopes that no-one was using double
inversion.

It turns out that the XOR:ing between the explicit
inversion was indeed in use, so we need to restore the
old semantics where both ways of inversion are checked
and the end result XOR:ed.

Reported-by: Javier Martinez Canillas 
Tested-by: Javier Martinez Canillas 
Signed-off-by: Linus Walleij 
Signed-off-by: Ulf Hansson

mmc: host: switch OF parser to use gpio descriptors

2014-09-09T12:25:14+00:00

This switches the central MMC OF parser to use gpio descriptors
instead of grabbing GPIOs explicitly from the device tree.
This strips out an unecessary use of the integer-based GPIO
API that we want to get rid of, cuts down on code as the
gpio descriptor code will handle active low flags.

Acked-by: Alexandre Courbot 
Signed-off-by: Linus Walleij 
Signed-off-by: Ulf Hansson

mmc: implement Driver Stage Register handling

2014-09-09T11:59:07+00:00

Some eMMC and SD cards implement a DSR register that allows to tune
raise/fall times and drive strength of the CMD and DATA outputs.
The values to use depend on the card in use and the host.
It might be needed to reduce the drive strength to prevent voltage peaks
above the host's specification.

Implement a 'dsr' devicetree property that allows to specify the value
to set the DSR to. For non-dt setups the new members of mmc_host can be
set by board code.

This patch was initially authored by Sascha Hauer. It contains
improvements authored by Markus Niebel and Uwe Kleine-König.

Signed-off-by: Sascha Hauer 
Signed-off-by: Markus Niebel 
Signed-off-by: Uwe Kleine-König 
Signed-off-by: Ulf Hansson

mmc: core: add DT bindings for eMMC HS400 1.8/1.2V

2014-05-12T22:08:10+00:00

Provide the option to configure these speed modes per host,
for those host driver's that can't distinguish this in runtime.
Specially, if host can support HS400, it means that host can also
support HS200.

Signed-off-by: Seungwon Jeon 
Signed-off-by: Ulf Hansson 
Signed-off-by: Chris Ball

Merge tag 'mmc-updates-for-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc

2014-04-09T15:39:39+00:00

Pull MMC updates from Chris Ball:
 "MMC highlights for 3.15:

  Core:
   - CONFIG_MMC_UNSAFE_RESUME=y is now default behavior
   - DT bindings for SDHCI UHS, eMMC HS200, high-speed DDR, at 1.8/1.2V
   - Add GPIO descriptor based slot-gpio card detect API

  Drivers:
   - dw_mmc: Refactor SOCFPGA support as a variant inside dw_mmc-pltfm.c
   - mmci: Support HW busy detection on ux500
   - omap: Support MMC_ERASE
   - omap_hsmmc: Support MMC_PM_KEEP_POWER, MMC_PM_WAKE_SDIO_IRQ, (a)cmd23
   - rtsx: Support pre-req/post-req async
   - sdhci: Add support for Realtek RTS5250 controllers
   - sdhci-acpi: Add support for 80860F16, fix 80860F14/SDIO card detect
   - sdhci-msm: Add new driver for Qualcomm SDHCI chipset support
   - sdhci-pxav3: Add support for Marvell Armada 380 and 385 SoCs"

* tag 'mmc-updates-for-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (102 commits)
  mmc: sdhci-acpi: Intel SDIO has broken card detect
  mmc: sdhci-pxav3: add support for the Armada 38x SDHCI controller
  mmc: sdhci-msm: Add platform_execute_tuning implementation
  mmc: sdhci-msm: Initial support for Qualcomm chipsets
  mmc: sdhci-msm: Qualcomm SDHCI binding documentation
  sdhci: only reprogram retuning timer when flag is set
  mmc: rename ARCH_BCM to ARCH_BCM_MOBILE
  mmc: sdhci: Allow for irq being shared
  mmc: sdhci-acpi: Add device id 80860F16
  mmc: sdhci-acpi: Fix broken card detect for ACPI HID 80860F14
  mmc: slot-gpio: Add GPIO descriptor based CD GPIO API
  mmc: slot-gpio: Split out CD IRQ request into a separate function
  mmc: slot-gpio: Record GPIO descriptors instead of GPIO numbers
  Revert "dts: socfpga: Add support for SD/MMC on the SOCFPGA platform"
  mmc: sdhci-spear: use generic card detection gpio support
  mmc: sdhci-spear: remove support for power gpio
  mmc: sdhci-spear: simplify resource handling
  mmc: sdhci-spear: fix platform_data usage
  mmc: sdhci-spear: fix error handling paths for DT
  mmc: sdhci-bcm-kona: fix build errors when built-in
  ...