target/linux/brcm2708/patches-4.4/0199-BCM270X_DT-Add-1-bit-SDIO-using-minimal-pins.patch

   1 From e1b1b8a6f9dbdcf019b8975d5ced5a0393b23dd3 Mon Sep 17 00:00:00 2001
   2 From: campag <dave-lowe@ntlworld.com>
   3 Date: Wed, 24 Feb 2016 16:45:42 +0000
   4 Subject: [PATCH 199/423] BCM270X_DT: Add 1-bit SDIO using minimal pins...
   5
   6 ... for that mode: GPIOs 22-25.
   7 ---
   8  arch/arm/boot/dts/overlays/README                | 21 ++++++++++++++
   9  arch/arm/boot/dts/overlays/sdio-1bit-overlay.dts | 36 ++++++++++++++++++++++++
  10  2 files changed, 57 insertions(+)
  11  create mode 100644 arch/arm/boot/dts/overlays/sdio-1bit-overlay.dts
  12
  13 --- a/arch/arm/boot/dts/overlays/README
  14 +++ b/arch/arm/boot/dts/overlays/README
  15 @@ -709,6 +709,27 @@ Params: overclock_50            SD Clock
  16          bus_width               Set the SDIO host bus width (default 4 bits)
  17
  18
  19 +Name:   sdio-1bit
  20 +Info:   Selects the bcm2835-sdhost SD/MMC driver, optionally with overclock,
  21 +        and enables 1-bit SDIO via GPIOs 22-25.
  22 +Load:   dtoverlay=sdio-1bit,<param>=<val>
  23 +Params: overclock_50            SD Clock (in MHz) to use when the MMC framework
  24 +                                requests 50MHz
  25 +
  26 +        sdio_overclock          SDIO Clock (in MHz) to use when the MMC
  27 +                                framework requests 50MHz
  28 +
  29 +        force_pio               Disable DMA support (default off)
  30 +
  31 +        pio_limit               Number of blocks above which to use DMA
  32 +                                (default 1)
  33 +
  34 +        debug                   Enable debug output (default off)
  35 +
  36 +        poll_once               Disable SDIO-device polling every second
  37 +                                (default on: polling once at boot-time)
  38 +
  39 +
  40  Name:   sdtweak
  41  Info:   Tunes the bcm2835-sdhost SD/MMC driver
  42  Load:   dtoverlay=sdtweak,<param>=<val>
  43 --- /dev/null
  44 +++ b/arch/arm/boot/dts/overlays/sdio-1bit-overlay.dts
  45 @@ -0,0 +1,36 @@
  46 +/* Enable 1-bit SDIO from MMC interface via GPIOs 22-25. Includes sdhost overlay. */
  47 +
  48 +/include/ "sdhost-overlay.dts"
  49 +
  50 +/{
  51 +       compatible = "brcm,bcm2708";
  52 +
  53 +       fragment@3 {
  54 +               target = <&mmc>;
  55 +               sdio_mmc: __overlay__ {
  56 +                       compatible = "brcm,bcm2835-mmc";
  57 +                       pinctrl-names = "default";
  58 +                       pinctrl-0 = <&sdio_pins>;
  59 +                       non-removable;
  60 +                       bus-width = <1>;
  61 +                       brcm,overclock-50 = <0>;
  62 +                       status = "okay";
  63 +               };
  64 +       };
  65 +
  66 +       fragment@4 {
  67 +               target = <&gpio>;
  68 +               __overlay__ {
  69 +                       sdio_pins: sdio_pins {
  70 +                               brcm,pins = <22 23 24 25>;
  71 +                               brcm,function = <7 7 7 7>; /* ALT3 = SD1 */
  72 +                               brcm,pull = <0 2 2 2>;
  73 +                       };
  74 +               };
  75 +       };
  76 +
  77 +       __overrides__ {
  78 +               poll_once = <&sdio_mmc>,"non-removable?";
  79 +               sdio_overclock = <&sdio_mmc>,"brcm,overclock-50:0";
  80 +       };
  81 +};