cmd: add ADC cli commands

Add an 'adc' cli command to get information from adc devices and to read
"single shot" data.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>

cmd/Kconfig

@@ -601,6 +601,14 @@ config CMD_ARMFLASH
 	help
 	  ARM Ltd reference designs flash partition access
 
+config CMD_ADC
+	bool "adc - Access Analog to Digital Converters info and data"
+	select ADC
+	select DM_REGULATOR
+	help
+	  Shows ADC device info and permit printing one-shot analog converted
+	  data from a named Analog to Digital Converter.
+
 config CMD_CLK
 	bool "clk - Show clock frequencies"
 	help

cmd/Makefile

@@ -12,6 +12,7 @@ obj-y += version.o
 
 # command
 obj-$(CONFIG_CMD_AES) += aes.o
+obj-$(CONFIG_CMD_ADC) += adc.o
 obj-$(CONFIG_CMD_ARMFLASH) += armflash.o
 obj-y += blk_common.o
 obj-$(CONFIG_SOURCE) += source.o

cmd/adc.c

@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ */
+#include <common.h>
+#include <command.h>
+#include <dm.h>
+#include <adc.h>
+
+static int do_adc_list(cmd_tbl_t *cmdtp, int flag, int argc,
+		       char *const argv[])
+{
+	struct udevice *dev;
+	int ret;
+
+	ret = uclass_first_device_err(UCLASS_ADC, &dev);
+	if (ret) {
+		printf("No available ADC device\n");
+		return CMD_RET_FAILURE;
+	}
+
+	do {
+		printf("- %s\n", dev->name);
+
+		ret = uclass_next_device(&dev);
+		if (ret)
+			return CMD_RET_FAILURE;
+	} while (dev);
+
+	return CMD_RET_SUCCESS;
+}
+
+static int do_adc_info(cmd_tbl_t *cmdtp, int flag, int argc,
+		       char *const argv[])
+{
+	struct udevice *dev;
+	unsigned int data_mask;
+	int ret, vss, vdd;
+
+	if (argc < 2)
+		return CMD_RET_USAGE;
+
+	ret = uclass_get_device_by_name(UCLASS_ADC, argv[1], &dev);
+	if (ret) {
+		printf("Unknown ADC device %s\n", argv[1]);
+		return CMD_RET_FAILURE;
+	}
+
+	printf("ADC Device '%s' :\n", argv[1]);
+
+	ret = adc_data_mask(dev, &data_mask);
+	if (!ret)
+		printf("data mask: %x\n", data_mask);
+
+	ret = adc_vdd_value(dev, &vdd);
+	if (!ret)
+		printf("vdd: %duV\n", vdd);
+
+	ret = adc_vss_value(dev, &vss);
+	if (!ret)
+		printf("vss: %duV\n", vss);
+
+	return CMD_RET_SUCCESS;
+}
+
+static int do_adc_single(cmd_tbl_t *cmdtp, int flag, int argc,
+			 char *const argv[])
+{
+	unsigned int data;
+	int ret;
+
+	if (argc < 3)
+		return CMD_RET_USAGE;
+
+	ret = adc_channel_single_shot(argv[1], simple_strtol(argv[2], NULL, 0),
+				      &data);
+	if (ret) {
+		printf("Error getting single shot for device %s channel %s\n",
+		       argv[1], argv[2]);
+		return CMD_RET_FAILURE;
+	}
+
+	printf("%u\n", data);
+
+	return CMD_RET_SUCCESS;
+}
+
+static cmd_tbl_t cmd_adc_sub[] = {
+	U_BOOT_CMD_MKENT(list, 1, 1, do_adc_list, "", ""),
+	U_BOOT_CMD_MKENT(info, 2, 1, do_adc_info, "", ""),
+	U_BOOT_CMD_MKENT(single, 3, 1, do_adc_single, "", ""),
+};
+
+static int do_adc(cmd_tbl_t *cmdtp, int flag, int argc,
+		  char *const argv[])
+{
+	cmd_tbl_t *c;
+
+	if (argc < 2)
+		return CMD_RET_USAGE;
+
+	/* Strip off leading 'adc' command argument */
+	argc--;
+	argv++;
+
+	c = find_cmd_tbl(argv[0], &cmd_adc_sub[0], ARRAY_SIZE(cmd_adc_sub));
+
+	if (c)
+		return c->cmd(cmdtp, flag, argc, argv);
+	else
+		return CMD_RET_USAGE;
+}
+
+static char adc_help_text[] =
+	"list - list ADC devices\n"
+	"adc info <name> - Get ADC device info\n"
+	"adc single <name> <channel> - Get Single data of ADC device channel";
+
+U_BOOT_CMD(adc, 4, 1, do_adc, "ADC sub-system", adc_help_text);