rockchip: rk3399: Add support for chromebook_kevin

Add support for Kevin, an RK3399-based convertible chromebook that is
very similar to Bob. This patch is mostly based on existing support for
Bob, with only minor changes for Kevin-specific things.

Unlike other Gru boards, coreboot sets Kevin's center logic to 925 mV,
so adjust it here in the dts as well. The rk3399-gru-kevin devicetree
has an unknown event code reference which has to be defined, set it
to the Linux counterpart. The new defconfig is copied from Bob with the
diffconfig:

     DEFAULT_DEVICE_TREE "rk3399-gru-bob" -> "rk3399-gru-kevin"
     DEFAULT_FDT_FILE "rockchip/rk3399-gru-bob.dtb" -> "rockchip/rk3399-gru-kevin.dtb"
     VIDEO_ROCKCHIP_MAX_XRES 1280 -> 2400
     VIDEO_ROCKCHIP_MAX_YRES 800 -> 1600
    +TARGET_CHROMEBOOK_KEVIN y

With this Kevin can boot from SPI flash to a usable U-Boot prompt on the
display with the keyboard working, but cannot boot into Linux for
unknown reasons.

eMMC starts in a working state but fails to re-init, microSD card works
but at a lower-than-expected speed, USB works but causes a hang on
de-init. There are known workarounds to solve eMMC and USB issues.

Cc: Marty E. Plummer <hanetzer@startmail.com>
Cc: Simon Glass <sjg@chromium.org>
[Alper: commit message, resync config with Bob, update MAINTAINERS,
        add to Rockchip doc, add Kconfig help message, set regulator]
Co-developed-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/arch/arm/dts/rk3399-gru-kevin-u-boot.dtsi b/arch/arm/dts/rk3399-gru-kevin-u-boot.dtsi
new file mode 100644
index 0000000000..c03bd48e95
--- /dev/null
+++ b/arch/arm/dts/rk3399-gru-kevin-u-boot.dtsi
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 Jagan Teki <jagan@amarulasolutions.com>
+ */
+
+#include "rk3399-gru-u-boot.dtsi"
+#include "rk3399-sdram-lpddr3-samsung-4GB-1866.dtsi"
+
+&ppvar_centerlogic_pwm {
+	regulator-init-microvolt = <925000>;
+};