cmd: add 'charge' cmd support

It calls charge display.

Change-Id: Iced07ec388b48f6849516cc67715b6a50860bc9c
Signed-off-by: Joseph Chen <chenjh@rock-chips.com>

cmd/Kconfig

@@ -1219,6 +1219,11 @@ config CMD_REGULATOR
 	  the limits, which are found in device-tree and are kept in regulator's
 	  uclass platdata structure.
 
+config CMD_CHARGE_DISPLAY
+	bool "Enable Driver Model Charge Display command"
+	help
+	  Support U-Boot charge display.
+
 endmenu
 
 menu "Security commands"

cmd/Makefile

@@ -33,6 +33,7 @@ obj-$(CONFIG_CMD_CLK) += clk.o
 obj-$(CONFIG_CMD_CONFIG) += config.o
 obj-$(CONFIG_CMD_CONSOLE) += console.o
 obj-$(CONFIG_CMD_CPU) += cpu.o
+obj-$(CONFIG_CMD_CHARGE_DISPLAY) += charge.o
 obj-$(CONFIG_DATAFLASH_MMC_SELECT) += dataflash_mmc_mux.o
 obj-$(CONFIG_CMD_DATE) += date.o
 obj-$(CONFIG_CMD_DEMO) += demo.o

cmd/charge.c

@@ -0,0 +1,38 @@
+/*
+ * (C) Copyright 2017 Rockchip Electronics Co., Ltd
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <command.h>
+#include <dm.h>
+#include <power/charge_display.h>
+
+static int charge_display(cmd_tbl_t *cmdtp, int flag, int argc,
+			  char *const argv[])
+{
+	int ret;
+	struct udevice *dev;
+
+	if (argc != 1)
+		return CMD_RET_USAGE;
+
+	ret = uclass_get_device(UCLASS_CHARGE_DISPLAY, 0, &dev);
+	if (ret) {
+		if (ret != -ENODEV) {
+			printf("Get UCLASS CHARGE DISPLAY failed: %d\n", ret);
+			return ret;
+		}
+
+		return 0;
+	}
+
+	return charge_display_show(dev);
+}
+
+U_BOOT_CMD(
+	charge, 1, 0, charge_display,
+	"Charge display",
+	""
+);