To support SOCs which specifies specific MMC power sequences, document
some MMC DT bindings to be able to describe these hardwares.
Let's also document bindings for a simple MMC power sequence provider,
which purpose is to support a set of common properties between various
SOCs.
In this initial step, let's also document a top level description of
the MMC power sequence and describe the compatible string used for the
simple MMC power sequence provider.
The simple MMC power sequence provider will initially support a reset
GPIO. From several earlier posted patches, it's clear that such
hardware exists. Especially some WLAN chips which are attached to an
SDIO interface may use a GPIO reset.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
While SDIO devices are runtime probable they sometimes need nonprobable
additional information on embedded systems, like an additional gpio
interrupt or a clock. This binding describes how to add child nodes to the
devicetree to supply this information.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
[hdegoede@redhat.com: Documented the need for #address- and #size-cells]
[hdegoede@redhat.com: Added a real world example]
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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 <s.hauer@pengutronix.de>
Signed-off-by: Markus Niebel <Markus.Niebel@tq-group.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Currently the documentation doesn't match the code in mmc_of_parse. This
patch rectifies this.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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 <tgih.jun@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
Provide the option to configure these speed modes per host, for those
host driver's that can't distinguish this in runtime.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
Provide the option to configure these speed modes per host, for those
host driver's that can't distinguish this in runtime.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <chris@printf.net>
Provide the option to configure these speed modes per host, for those
host driver's that can't distinguish this in runtime.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <chris@printf.net>
The DT-binding for MMC_CAP2_FULL_PWR_CYCLE, is used to indicate whether
it is possible to perform a full power cycle of the card.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Many MMC capability flags are platform-dependent and are traditionally set
in platform data. With DT often each such capability requires a special
binding. Add bindings for MMC_CAP_SD_HIGHSPEED, MMC_CAP_MMC_HIGHSPEED,
MMC_CAP_POWER_OFF_CARD and MMC_CAP_SDIO_IRQ capabilities. Also add code to
DT parser to look up "keep-power-in-suspend" and "enable-sdio-wakeup"
bindings and set MMC_PM_KEEP_POWER and MMC_PM_WAKE_SDIO_IRQ respectively,
if found.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
Clarify ways to specify write-protect and card-detect MMC lines in FDT.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
None of mmc drivers implements bus-width as a required device tree
property. Instead, some drivers like atmel-mci, dw_mmc, sdhci-s3c
implement it as an optional one, and will force bus width to be 1
when the property is absent. Let's change the common binding to
reflect what the drivers are usually doing.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
The file Documentation/devicetree/bindings/mmc/mmc.txt is common for all
MMC host drivers. Use a generic MMC host reference instead of an SDHCI
left-over.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
The OLPC XO-1.75 laptop includes a SDHCI controller which is 1.8v
capable, and it truthfully reports so in its capabilities. This
alternate voltage is used for driving new "UHS-I" SD cards at their
full speed.
However, what the controller doesn't know is that the motherboard
physically doesn't have a 1.8v supply available, so attempting to
switch to the 1.8v level will result in a situation that cannot be
recovered from without physically replugging the SD card.
Add a device tree flag that can be used on systems like these,
and hook it up to the equivalent SDHCI quirk.
Signed-off-by: Daniel Drake <dsd@laptop.org>
Reviewed-by: Philip Rakity <prakity@nvidia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Add documentation for pm capabilties such as MMC_PM_KEEP_POWER
and MMC_PM_WAKE_SDIO_IRQ.
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Even though these aren't parsed by the MMC driver, make clear that
they're required by the OF core. (Also, a few typo fixes.)
Signed-off-by: Chris Ball <cjb@laptop.org>
This patch unifies the current DT MMC bindings documentation and code,
adds generic MMC DT bindings documentation, and updates .dts files for
consistency.
[cjb: typo fixes, addition of max-frequency property]
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Ulf Hansson