Some exynos boards require special handling of nRESET_OUT line for eMMC memory to perform complete reboot e.g. Odroid X2/U3/XU3 boards.

This will support eMMC reset using DT from reset_misc of samsung common board file.

Signed-off-by: Joonyoung Shim jy0922.shim@samsung.com --- board/samsung/common/board.c | 28 ++++++++++++++++++++++++++ board/samsung/odroid/odroid.c | 8 -------- doc/device-tree-bindings/exynos/emmc-reset.txt | 15 ++++++++++++++ 3 files changed, 43 insertions(+), 8 deletions(-) create mode 100644 doc/device-tree-bindings/exynos/emmc-reset.txt

diff --git a/board/samsung/common/board.c b/board/samsung/common/board.c index 8b4c8e9..da2245f 100644 --- a/board/samsung/common/board.c +++ b/board/samsung/common/board.c @@ -355,3 +355,31 @@ int misc_init_r(void) return 0; } #endif + +void reset_misc(void) +{ + struct gpio_desc gpio = {}; + int node; + + node = fdt_node_offset_by_compatible(gd->fdt_blob, 0, + "samsung,emmc-reset"); + if (node < 0) + return; + + gpio_request_by_name_nodev(gd->fdt_blob, node, "reset-gpio", 0, &gpio, + GPIOD_IS_OUT); + + if (dm_gpio_is_valid(&gpio)) { + /* + * Reset eMMC + * + * FIXME: Need to optimize delay time. Minimum 1usec pulse is + * required by 'JEDEC Standard No.84-A441' (eMMC) + * document but real delay time is expected to greater + * than 1usec. + */ + dm_gpio_set_value(&gpio, 0); + mdelay(10); + dm_gpio_set_value(&gpio, 1); + } +} diff --git a/board/samsung/odroid/odroid.c b/board/samsung/odroid/odroid.c index b7d2381..b648832 100644 --- a/board/samsung/odroid/odroid.c +++ b/board/samsung/odroid/odroid.c @@ -515,11 +515,3 @@ int board_usb_init(int index, enum usb_init_type init) return s3c_udc_probe(&s5pc210_otg_data); } #endif - -void reset_misc(void) -{ - /* Reset eMMC*/ - gpio_set_value(EXYNOS4X12_GPIO_K12, 0); - mdelay(10); - gpio_set_value(EXYNOS4X12_GPIO_K12, 1); -} diff --git a/doc/device-tree-bindings/exynos/emmc-reset.txt b/doc/device-tree-bindings/exynos/emmc-reset.txt new file mode 100644 index 0000000..5e7ba26 --- /dev/null +++ b/doc/device-tree-bindings/exynos/emmc-reset.txt @@ -0,0 +1,15 @@ +* Samsung eMMC reset + +Some exynos boards require special handling of nRESET_OUT line for eMMC memory +to perform complete reboot. + +Required properties: +- compatible: should be "samsung,emmc-reset" +- reset-gpio: gpio chip for eMMC reset. + +Example: + +emmc-reset { + compatible = "samsung,emmc-reset"; + reset-gpio = <&gpk1 2 0>; +};