Merge tag 'mmc-updates-for-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc

Pull MMC update from Chris Ball:
 "MMC highlights for 3.9:

  Core:
   - Support for packed commands in eMMC 4.5.  (This requires a host
     capability to be turned on.  It increases write throughput by 20%+,
     but may also increase average write latency; more testing needed.)
   - Add DT bindings for capability flags.
   - Add mmc_of_parse() for shared DT parsing between drivers.

  Drivers:
   - android-goldfish: New MMC driver for the Android Goldfish emulator.
   - mvsdio: Add DT bindings, pinctrl, use slot-gpio for card detection.
   - omap_hsmmc: Fix boot hangs with RPMB partitions.
   - sdhci-bcm2835: New driver for controller used by Raspberry Pi.
   - sdhci-esdhc-imx: Add 8-bit data, auto CMD23 support, use slot-gpio.
   - sh_mmcif: Add support for eMMC DDR, bundled MMCIF IRQs.
   - tmio_mmc: Add DT bindings, support for vccq regulator"

* tag 'mmc-updates-for-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (92 commits)
  mmc: tegra: assume CONFIG_OF, remove platform data
  mmc: add DT bindings for more MMC capability flags
  mmc: tmio: add support for the VccQ regulator
  mmc: tmio: remove unused and deprecated symbols
  mmc: sh_mobile_sdhi: use managed resource allocations
  mmc: sh_mobile_sdhi: remove unused .pdata field
  mmc: tmio-mmc: parse device-tree bindings
  mmc: tmio-mmc: define device-tree bindings
  mmc: sh_mmcif: use mmc_of_parse() to parse standard MMC DT bindings
  mmc: (cosmetic) remove "extern" from function declarations
  mmc: provide a standard MMC device-tree binding parser centrally
  mmc: detailed definition of CD and WP MMC line polarities in DT
  mmc: sdhi, tmio: only check flags in tmio-mmc driver proper
  mmc: sdhci: Fix parameter of sdhci_do_start_signal_voltage_switch()
  mmc: sdhci: check voltage range only on regulators aware of voltage value
  mmc: bcm2835: set SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK
  mmc: support packed write command for eMMC4.5 devices
  mmc: add packed command feature of eMMC4.5
  mmc: rtsx: remove driving adjustment
  mmc: use regulator_can_change_voltage() instead of regulator_count_voltages
  ...

1 files changed, 28 insertions, 6 deletions

diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt
index a591c6741d75..85aada2263d5 100644
--- a/Documentation/devicetree/bindings/mmc/mmc.txt
+++ b/Documentation/devicetree/bindings/mmc/mmc.txt
@@ -6,23 +6,45 @@ Interpreted by the OF core:
 - reg: Registers location and length.
 - interrupts: Interrupts used by the MMC controller.
 
-Required properties:
-- bus-width: Number of data lines, can be <1>, <4>, or <8>
-
 Card detection:
-If no property below is supplied, standard SDHCI card detect is used.
+If no property below is supplied, host native card detect is used.
 Only one of the properties in this section should be supplied:
   - broken-cd: There is no card detection available; polling must be used.
   - cd-gpios: Specify GPIOs for card detection, see gpio binding
   - non-removable: non-removable slot (like eMMC); assume always present.
 
 Optional properties:
+- bus-width: Number of data lines, can be <1>, <4>, or <8>.  The default
+  will be <1> if the property is absent.
 - wp-gpios: Specify GPIOs for write protection, see gpio binding
-- cd-inverted: when present, polarity on the cd gpio line is inverted
-- wp-inverted: when present, polarity on the wp gpio line is inverted
+- cd-inverted: when present, polarity on the CD line is inverted. See the note
+  below for the case, when a GPIO is used for the CD line
+- wp-inverted: when present, polarity on the WP line is inverted. See the note
+  below for the case, when a GPIO is used for the WP line
 - max-frequency: maximum operating clock frequency
 - no-1-8-v: when present, denotes that 1.8v card voltage is not supported on
   this system, even if the controller claims it is.
+- cap-sd-highspeed: SD high-speed timing is supported
+- cap-mmc-highspeed: MMC high-speed timing is supported
+- cap-power-off-card: powering off the card is safe
+- cap-sdio-irq: enable SDIO IRQ signalling on this interface
+
+*NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line
+polarity properties, we have to fix the meaning of the "normal" and "inverted"
+line levels. We choose to follow the SDHCI standard, which specifies both those
+lines as "active low." Therefore, using the "cd-inverted" property means, that
+the CD line is active high, i.e. it is high, when a card is inserted. Similar
+logic applies to the "wp-inverted" property.
+
+CD and WP lines can be implemented on the hardware in one of two ways: as GPIOs,
+specified in cd-gpios and wp-gpios properties, or as dedicated pins. Polarity of
+dedicated pins can be specified, using *-inverted properties. GPIO polarity can
+also be specified using the OF_GPIO_ACTIVE_LOW flag. This creates an ambiguity
+in the latter case. We choose to use the XOR logic for GPIO CD and WP lines.
+This means, the two properties are "superimposed," for example leaving the
+OF_GPIO_ACTIVE_LOW flag clear and specifying the respective *-inverted
+property results in a double-inversion and actually means the "normal" line
+polarity is in effect.
 
 Optional SDIO properties:
 - keep-power-in-suspend: Preserves card power during a suspend/resume cycle