From 6618e478954d2866754798c3b07805dc9dbb2fc4 Mon Sep 17 00:00:00 2001 From: Doug Anderson Date: Wed, 10 Dec 2014 12:55:29 -0800 Subject: [PATCH] ARM: dts: rockchip: bump sd card pin drive strength up on rk3288-evb It seems that ever since (536f6b9 mmc: dw_mmc: Reset DMA before enabling IDMAC) landed upstream that SD cards have been very unhappy on rk3288-evb. They were a little unhappy before that change, but after that change they're REALLY unhappy. It turns out that the above fix happens to fix a corruption when reading card information during probe time. Without the fix we didn't detect that high speed SD cards could actually support high speed. With the fix we suddenly detect that they're high speed and we try to use them at 50MHz. That doesn't work so well on EVB with the default drive strength (maybe because there are two physical SD card slots hooked up to the same pin?). Fix the problem by bumping up the drive strength of the sdmmc lines. Signed-off-by: Doug Anderson Fixes: 536f6b91d21b ("mmc: dw_mmc: Reset DMA before enabling IDMAC") Signed-off-by: Heiko Stuebner --- arch/arm/boot/dts/rk3288-evb.dtsi | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/arch/arm/boot/dts/rk3288-evb.dtsi b/arch/arm/boot/dts/rk3288-evb.dtsi index 3e067dd65d0c..6194d673e80b 100644 --- a/arch/arm/boot/dts/rk3288-evb.dtsi +++ b/arch/arm/boot/dts/rk3288-evb.dtsi @@ -155,6 +155,15 @@ }; &pinctrl { + pcfg_pull_none_drv_8ma: pcfg-pull-none-drv-8ma { + drive-strength = <8>; + }; + + pcfg_pull_up_drv_8ma: pcfg-pull-up-drv-8ma { + bias-pull-up; + drive-strength = <8>; + }; + backlight { bl_en: bl-en { rockchip,pins = <7 2 RK_FUNC_GPIO &pcfg_pull_none>; @@ -173,6 +182,27 @@ }; }; + sdmmc { + /* + * Default drive strength isn't enough to achieve even + * high-speed mode on EVB board so bump up to 8ma. + */ + sdmmc_bus4: sdmmc-bus4 { + rockchip,pins = <6 16 RK_FUNC_1 &pcfg_pull_up_drv_8ma>, + <6 17 RK_FUNC_1 &pcfg_pull_up_drv_8ma>, + <6 18 RK_FUNC_1 &pcfg_pull_up_drv_8ma>, + <6 19 RK_FUNC_1 &pcfg_pull_up_drv_8ma>; + }; + + sdmmc_clk: sdmmc-clk { + rockchip,pins = <6 20 RK_FUNC_1 &pcfg_pull_none_drv_8ma>; + }; + + sdmmc_cmd: sdmmc-cmd { + rockchip,pins = <6 21 RK_FUNC_1 &pcfg_pull_up_drv_8ma>; + }; + }; + usb { host_vbus_drv: host-vbus-drv { rockchip,pins = <0 14 RK_FUNC_GPIO &pcfg_pull_none>; -- 2.20.1