dm: Enable gpio command to support driver model

Now that named GPIO banks are supported, along with a way of obtaining
the status of a GPIO (input or output), we can provide an enhanced
GPIO command for driver model. Where the driver provides its own operation
for obtaining the GPIO state, this is used, otherwise a generic version
is sufficient.

Signed-off-by: Simon Glass <sjg@chromium.org>

common/cmd_gpio.c

@@ -8,7 +8,7 @@
 
 #include <common.h>
 #include <command.h>
-
+#include <dm.h>
 #include <asm/gpio.h>
 
 #ifndef name_to_gpio
@@ -22,25 +22,115 @@ enum gpio_cmd {
 	GPIO_TOGGLE,
 };
 
+#if defined(CONFIG_DM_GPIO) && !defined(gpio_status)
+static const char * const gpio_function[] = {
+	"input",
+	"output",
+	"unknown",
+};
+
+static void show_gpio(struct device *dev, const char *bank_name, int offset)
+{
+	struct dm_gpio_ops *ops = gpio_get_ops(dev);
+	char buf[80];
+	int ret;
+
+	*buf = '\0';
+	if (ops->get_state) {
+		ret = ops->get_state(dev, offset, buf, sizeof(buf));
+		if (ret) {
+			puts("<unknown>");
+			return;
+		}
+	} else {
+		int func =  GPIOF_UNKNOWN;
+		int ret;
+
+		if (ops->get_function) {
+			ret = ops->get_function(dev, offset);
+			if (ret >= 0 && ret < ARRAY_SIZE(gpio_function))
+				func = ret;
+		}
+		sprintf(buf, "%s%u: %8s %d", bank_name, offset,
+			gpio_function[func], ops->get_value(dev, offset));
+	}
+
+	puts(buf);
+	puts("\n");
+}
+
+static int do_gpio_status(const char *gpio_name)
+{
+	struct device *dev;
+	int newline = 0;
+	int ret;
+
+	if (gpio_name && !*gpio_name)
+		gpio_name = NULL;
+	for (ret = uclass_first_device(UCLASS_GPIO, &dev);
+	     dev;
+	     ret = uclass_next_device(&dev)) {
+		const char *bank_name;
+		int num_bits;
+
+		bank_name = gpio_get_bank_info(dev, &num_bits);
+
+		if (!gpio_name || !bank_name ||
+		    !strncmp(gpio_name, bank_name, strlen(bank_name))) {
+			const char *p = NULL;
+			int offset;
+
+			if (bank_name) {
+				if (newline)
+					putc('\n');
+				printf("Bank %s:\n", bank_name);
+			}
+			newline = 1;
+			if (gpio_name && bank_name) {
+				p = gpio_name + strlen(bank_name);
+				offset = simple_strtoul(p, NULL, 10);
+				show_gpio(dev, bank_name, offset);
+			} else {
+				for (offset = 0; offset < num_bits; offset++)
+					show_gpio(dev, bank_name, offset);
+			}
+		}
+	}
+
+	return ret;
+}
+#endif
+
 static int do_gpio(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
-	int gpio;
+	unsigned int gpio;
 	enum gpio_cmd sub_cmd;
 	ulong value;
-	const char *str_cmd, *str_gpio;
+	const char *str_cmd, *str_gpio = NULL;
+#ifdef CONFIG_DM_GPIO
+	int ret;
+#endif
 
+	if (argc < 2)
+ show_usage:
+		return CMD_RET_USAGE;
+	str_cmd = argv[1];
+	if (argc > 2)
+		str_gpio = argv[2];
+	if (!strcmp(str_cmd, "status")) {
+		/* Support deprecated gpio_status() */
 #ifdef gpio_status
-	if (argc == 2 && !strcmp(argv[1], "status")) {
 		gpio_status();
 		return 0;
-	}
+#elif defined(CONFIG_DM_GPIO)
+		return cmd_process_error(cmdtp, do_gpio_status(str_gpio));
+#else
+		goto show_usage;
 #endif
+	}
 
-	if (argc != 3)
- show_usage:
-		return CMD_RET_USAGE;
-	str_cmd = argv[1];
-	str_gpio = argv[2];
+	if (!str_gpio)
+		goto show_usage;
 
 	/* parse the behavior */
 	switch (*str_cmd) {
@@ -51,11 +141,23 @@ static int do_gpio(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		default:  goto show_usage;
 	}
 
+#if defined(CONFIG_DM_GPIO)
+	/*
+	 * TODO(sjg@chromium.org): For now we must fit into the existing GPIO
+	 * framework, so we look up the name here and convert it to a GPIO number.
+	 * Once all GPIO drivers are converted to driver model, we can change the
+	 * code here to use the GPIO uclass interface instead of the numbered
+	 * GPIO compatibility layer.
+	 */
+	ret = gpio_lookup_name(str_gpio, NULL, NULL, &gpio);
+	if (ret)
+		return cmd_process_error(cmdtp, ret);
+#else
 	/* turn the gpio name into a gpio number */
 	gpio = name_to_gpio(str_gpio);
 	if (gpio < 0)
 		goto show_usage;
-
+#endif
 	/* grab the pin before we tweak it */
 	if (gpio_request(gpio, "cmd_gpio")) {
 		printf("gpio: requesting pin %u failed\n", gpio);
@@ -84,6 +186,7 @@ static int do_gpio(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 }
 
 U_BOOT_CMD(gpio, 3, 0, do_gpio,
-	"input/set/clear/toggle gpio pins",
+	"query and control gpio pins",
 	"<input|set|clear|toggle> <pin>\n"
-	"    - input/set/clear/toggle the specified pin");
+	"    - input/set/clear/toggle the specified pin\n"
+	"gpio status [<bank> | <pin>]");