From 81f8a7be6642b4c26ab681b2e0f4c4120a6de1b0 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Wed, 1 Apr 2015 17:26:23 +0200 Subject: mmc: Add support for marking hpi as broken through devicetree The eMMC on a tablet I've will stop working / communicating as soon as the kernel executes: mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_HPI_MGMT, 1, card->ext_csd.generic_cmd6_time); There seems to be no way to reliable identify eMMC-s which have a broken hpi implementation, but at least for eMMC's which are soldered onto a board we can work around this by specifying that hpi is broken in devicetree. Signed-off-by: Hans de Goede Signed-off-by: Ulf Hansson --- Documentation/devicetree/bindings/mmc/mmc-card.txt | 31 ++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 Documentation/devicetree/bindings/mmc/mmc-card.txt (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/mmc/mmc-card.txt b/Documentation/devicetree/bindings/mmc/mmc-card.txt new file mode 100644 index 000000000000..a70fcd65b9ea --- /dev/null +++ b/Documentation/devicetree/bindings/mmc/mmc-card.txt @@ -0,0 +1,31 @@ +mmc-card / eMMC bindings +------------------------ + +This documents describes the devicetree bindings for a mmc-host controller +child node describing a mmc-card / an eMMC, see "Use of Function subnodes" +in mmc.txt + +Required properties: +-compatible : Must be "mmc-card" +-reg : Must be <0> + +Optional properties: +-broken-hpi : Use this to indicate that the mmc-card has a broken hpi + implementation, and that hpi should not be used + +Example: + +&mmc2 { + pinctrl-names = "default"; + pinctrl-0 = <&mmc2_pins_a>; + vmmc-supply = <®_vcc3v3>; + bus-width = <8>; + non-removable; + status = "okay"; + + mmccard: mmccard@0 { + reg = <0>; + compatible = "mmc-card"; + broken-hpi; + }; +}; -- cgit