X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=drivers%2Fgpio%2Fgpio-uclass.c;h=4cce11fe215f05b2cfbc1d55b5c4e020940b1ee6;hb=4fb6055211b28c525fb45463ebe5da2757d9abc7;hp=56bfd114665c91aafeb50d995cc02f6b79a683f7;hpb=08798026f24bd7c706e70372f8c323f0702c9a15;p=oweals%2Fu-boot.git

diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c
index 56bfd11466..4cce11fe21 100644
--- a/drivers/gpio/gpio-uclass.c
+++ b/drivers/gpio/gpio-uclass.c
@@ -7,71 +7,160 @@
 #include <common.h>
 #include <dm.h>
 #include <errno.h>
+#include <fdtdec.h>
+#include <malloc.h>
 #include <asm/gpio.h>
+#include <linux/ctype.h>
+
+DECLARE_GLOBAL_DATA_PTR;
 
 /**
  * gpio_to_device() - Convert global GPIO number to device, number
- * gpio:	The numeric representation of the GPIO
  *
  * Convert the GPIO number to an entry in the list of GPIOs
  * or GPIO blocks registered with the GPIO controller. Returns
  * entry on success, NULL on error.
+ *
+ * @gpio:	The numeric representation of the GPIO
+ * @desc:	Returns description (desc->flags will always be 0)
+ * @return 0 if found, -ENOENT if not found
  */
-static int gpio_to_device(unsigned int gpio, struct device **devp,
-			  unsigned int *offset)
+static int gpio_to_device(unsigned int gpio, struct gpio_desc *desc)
 {
 	struct gpio_dev_priv *uc_priv;
-	struct device *dev;
+	struct udevice *dev;
 	int ret;
 
 	for (ret = uclass_first_device(UCLASS_GPIO, &dev);
 	     dev;
 	     ret = uclass_next_device(&dev)) {
-		uc_priv = dev->uclass_priv;
+		uc_priv = dev_get_uclass_priv(dev);
 		if (gpio >= uc_priv->gpio_base &&
 		    gpio < uc_priv->gpio_base + uc_priv->gpio_count) {
-			*devp = dev;
-			*offset = gpio - uc_priv->gpio_base;
+			desc->dev = dev;
+			desc->offset = gpio - uc_priv->gpio_base;
+			desc->flags = 0;
 			return 0;
 		}
 	}
 
 	/* No such GPIO */
-	return ret ? ret : -EINVAL;
+	return ret ? ret : -ENOENT;
 }
 
-int gpio_lookup_name(const char *name, struct device **devp,
-		     unsigned int *offsetp, unsigned int *gpiop)
+int dm_gpio_lookup_name(const char *name, struct gpio_desc *desc)
 {
-	struct gpio_dev_priv *uc_priv;
-	struct device *dev;
+	struct gpio_dev_priv *uc_priv = NULL;
+	struct udevice *dev;
+	ulong offset;
+	int numeric;
 	int ret;
 
-	if (devp)
-		*devp = NULL;
+	numeric = isdigit(*name) ? simple_strtoul(name, NULL, 10) : -1;
 	for (ret = uclass_first_device(UCLASS_GPIO, &dev);
 	     dev;
 	     ret = uclass_next_device(&dev)) {
-		ulong offset;
 		int len;
 
-		uc_priv = dev->uclass_priv;
+		uc_priv = dev_get_uclass_priv(dev);
+		if (numeric != -1) {
+			offset = numeric - uc_priv->gpio_base;
+			/* Allow GPIOs to be numbered from 0 */
+			if (offset >= 0 && offset < uc_priv->gpio_count)
+				break;
+		}
+
 		len = uc_priv->bank_name ? strlen(uc_priv->bank_name) : 0;
 
-		if (!strncmp(name, uc_priv->bank_name, len)) {
-			if (strict_strtoul(name + len, 10, &offset))
-				continue;
-			if (devp)
-				*devp = dev;
-			if (offsetp)
-				*offsetp = offset;
-			if (gpiop)
-				*gpiop = uc_priv->gpio_base + offset;
-			return 0;
+		if (!strncasecmp(name, uc_priv->bank_name, len)) {
+			if (!strict_strtoul(name + len, 10, &offset))
+				break;
+		}
+	}
+
+	if (!dev)
+		return ret ? ret : -EINVAL;
+
+	desc->dev = dev;
+	desc->offset = offset;
+
+	return 0;
+}
+
+int gpio_lookup_name(const char *name, struct udevice **devp,
+		     unsigned int *offsetp, unsigned int *gpiop)
+{
+	struct gpio_desc desc;
+	int ret;
+
+	if (devp)
+		*devp = NULL;
+	ret = dm_gpio_lookup_name(name, &desc);
+	if (ret)
+		return ret;
+
+	if (devp)
+		*devp = desc.dev;
+	if (offsetp)
+		*offsetp = desc.offset;
+	if (gpiop) {
+		struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(desc.dev);
+
+		*gpiop = uc_priv->gpio_base + desc.offset;
+	}
+
+	return 0;
+}
+
+static int gpio_find_and_xlate(struct gpio_desc *desc,
+			       struct fdtdec_phandle_args *args)
+{
+	struct dm_gpio_ops *ops = gpio_get_ops(desc->dev);
+
+	/* Use the first argument as the offset by default */
+	if (args->args_count > 0)
+		desc->offset = args->args[0];
+	else
+		desc->offset = -1;
+	desc->flags = 0;
+
+	return ops->xlate ? ops->xlate(desc->dev, desc, args) : 0;
+}
+
+int dm_gpio_request(struct gpio_desc *desc, const char *label)
+{
+	struct udevice *dev = desc->dev;
+	struct gpio_dev_priv *uc_priv;
+	char *str;
+	int ret;
+
+	uc_priv = dev_get_uclass_priv(dev);
+	if (uc_priv->name[desc->offset])
+		return -EBUSY;
+	str = strdup(label);
+	if (!str)
+		return -ENOMEM;
+	if (gpio_get_ops(dev)->request) {
+		ret = gpio_get_ops(dev)->request(dev, desc->offset, label);
+		if (ret) {
+			free(str);
+			return ret;
 		}
 	}
+	uc_priv->name[desc->offset] = str;
 
-	return ret ? ret : -EINVAL;
+	return 0;
+}
+
+static int dm_gpio_requestf(struct gpio_desc *desc, const char *fmt, ...)
+{
+	va_list args;
+	char buf[40];
+
+	va_start(args, fmt);
+	vscnprintf(buf, sizeof(buf), fmt, args);
+	va_end(args);
+	return dm_gpio_request(desc, buf);
 }
 
 /**
@@ -79,24 +168,64 @@ int gpio_lookup_name(const char *name, struct device **devp,
  * gpio:	GPIO number
  * label:	Name for the requested GPIO
  *
+ * The label is copied and allocated so the caller does not need to keep
+ * the pointer around.
+ *
  * This function implements the API that's compatible with current
  * GPIO API used in U-Boot. The request is forwarded to particular
  * GPIO driver. Returns 0 on success, negative value on error.
  */
 int gpio_request(unsigned gpio, const char *label)
 {
-	unsigned int offset;
-	struct device *dev;
+	struct gpio_desc desc;
 	int ret;
 
-	ret = gpio_to_device(gpio, &dev, &offset);
+	ret = gpio_to_device(gpio, &desc);
 	if (ret)
 		return ret;
 
-	if (!gpio_get_ops(dev)->request)
-		return 0;
+	return dm_gpio_request(&desc, label);
+}
 
-	return gpio_get_ops(dev)->request(dev, offset, label);
+/**
+ * gpio_requestf() - [COMPAT] Request GPIO
+ * @gpio:	GPIO number
+ * @fmt:	Format string for the requested GPIO
+ * @...:	Arguments for the printf() format string
+ *
+ * This function implements the API that's compatible with current
+ * GPIO API used in U-Boot. The request is forwarded to particular
+ * GPIO driver. Returns 0 on success, negative value on error.
+ */
+int gpio_requestf(unsigned gpio, const char *fmt, ...)
+{
+	va_list args;
+	char buf[40];
+
+	va_start(args, fmt);
+	vscnprintf(buf, sizeof(buf), fmt, args);
+	va_end(args);
+	return gpio_request(gpio, buf);
+}
+
+int _dm_gpio_free(struct udevice *dev, uint offset)
+{
+	struct gpio_dev_priv *uc_priv;
+	int ret;
+
+	uc_priv = dev_get_uclass_priv(dev);
+	if (!uc_priv->name[offset])
+		return -ENXIO;
+	if (gpio_get_ops(dev)->free) {
+		ret = gpio_get_ops(dev)->free(dev, offset);
+		if (ret)
+			return ret;
+	}
+
+	free(uc_priv->name[offset]);
+	uc_priv->name[offset] = NULL;
+
+	return 0;
 }
 
 /**
@@ -109,17 +238,33 @@ int gpio_request(unsigned gpio, const char *label)
  */
 int gpio_free(unsigned gpio)
 {
-	unsigned int offset;
-	struct device *dev;
+	struct gpio_desc desc;
 	int ret;
 
-	ret = gpio_to_device(gpio, &dev, &offset);
+	ret = gpio_to_device(gpio, &desc);
 	if (ret)
 		return ret;
 
-	if (!gpio_get_ops(dev)->free)
-		return 0;
-	return gpio_get_ops(dev)->free(dev, offset);
+	return _dm_gpio_free(desc.dev, desc.offset);
+}
+
+static int check_reserved(struct gpio_desc *desc, const char *func)
+{
+	struct gpio_dev_priv *uc_priv;
+
+	if (!dm_gpio_is_valid(desc))
+		return -ENOENT;
+
+	uc_priv = dev_get_uclass_priv(desc->dev);
+	if (!uc_priv->name[desc->offset]) {
+		printf("%s: %s: error: gpio %s%d not reserved\n",
+		       desc->dev->name, func,
+		       uc_priv->bank_name ? uc_priv->bank_name : "",
+		       desc->offset);
+		return -EBUSY;
+	}
+
+	return 0;
 }
 
 /**
@@ -132,15 +277,17 @@ int gpio_free(unsigned gpio)
  */
 int gpio_direction_input(unsigned gpio)
 {
-	unsigned int offset;
-	struct device *dev;
+	struct gpio_desc desc;
 	int ret;
 
-	ret = gpio_to_device(gpio, &dev, &offset);
+	ret = gpio_to_device(gpio, &desc);
+	if (ret)
+		return ret;
+	ret = check_reserved(&desc, "dir_input");
 	if (ret)
 		return ret;
 
-	return gpio_get_ops(dev)->direction_input(dev, offset);
+	return gpio_get_ops(desc.dev)->direction_input(desc.dev, desc.offset);
 }
 
 /**
@@ -154,15 +301,81 @@ int gpio_direction_input(unsigned gpio)
  */
 int gpio_direction_output(unsigned gpio, int value)
 {
-	unsigned int offset;
-	struct device *dev;
+	struct gpio_desc desc;
 	int ret;
 
-	ret = gpio_to_device(gpio, &dev, &offset);
+	ret = gpio_to_device(gpio, &desc);
+	if (ret)
+		return ret;
+	ret = check_reserved(&desc, "dir_output");
 	if (ret)
 		return ret;
 
-	return gpio_get_ops(dev)->direction_output(dev, offset, value);
+	return gpio_get_ops(desc.dev)->direction_output(desc.dev,
+							desc.offset, value);
+}
+
+int dm_gpio_get_value(struct gpio_desc *desc)
+{
+	int value;
+	int ret;
+
+	ret = check_reserved(desc, "get_value");
+	if (ret)
+		return ret;
+
+	value = gpio_get_ops(desc->dev)->get_value(desc->dev, desc->offset);
+
+	return desc->flags & GPIOD_ACTIVE_LOW ? !value : value;
+}
+
+int dm_gpio_set_value(struct gpio_desc *desc, int value)
+{
+	int ret;
+
+	ret = check_reserved(desc, "set_value");
+	if (ret)
+		return ret;
+
+	if (desc->flags & GPIOD_ACTIVE_LOW)
+		value = !value;
+	gpio_get_ops(desc->dev)->set_value(desc->dev, desc->offset, value);
+	return 0;
+}
+
+int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags)
+{
+	struct udevice *dev = desc->dev;
+	struct dm_gpio_ops *ops = gpio_get_ops(dev);
+	int ret;
+
+	ret = check_reserved(desc, "set_dir");
+	if (ret)
+		return ret;
+
+	if (flags & GPIOD_IS_OUT) {
+		int value = flags & GPIOD_IS_OUT_ACTIVE ? 1 : 0;
+
+		if (flags & GPIOD_ACTIVE_LOW)
+			value = !value;
+		ret = ops->direction_output(dev, desc->offset, value);
+	} else  if (flags & GPIOD_IS_IN) {
+		ret = ops->direction_input(dev, desc->offset);
+	}
+	if (ret)
+		return ret;
+	/*
+	 * Update desc->flags here, so that GPIO_ACTIVE_LOW is honoured in
+	 * futures
+	 */
+	desc->flags = flags;
+
+	return 0;
+}
+
+int dm_gpio_set_dir(struct gpio_desc *desc)
+{
+	return dm_gpio_set_dir_flags(desc, desc->flags);
 }
 
 /**
@@ -176,15 +389,14 @@ int gpio_direction_output(unsigned gpio, int value)
  */
 int gpio_get_value(unsigned gpio)
 {
-	unsigned int offset;
-	struct device *dev;
 	int ret;
 
-	ret = gpio_to_device(gpio, &dev, &offset);
+	struct gpio_desc desc;
+
+	ret = gpio_to_device(gpio, &desc);
 	if (ret)
 		return ret;
-
-	return gpio_get_ops(dev)->get_value(dev, offset);
+	return dm_gpio_get_value(&desc);
 }
 
 /**
@@ -198,34 +410,314 @@ int gpio_get_value(unsigned gpio)
  */
 int gpio_set_value(unsigned gpio, int value)
 {
-	unsigned int offset;
-	struct device *dev;
+	struct gpio_desc desc;
 	int ret;
 
-	ret = gpio_to_device(gpio, &dev, &offset);
+	ret = gpio_to_device(gpio, &desc);
 	if (ret)
 		return ret;
-
-	return gpio_get_ops(dev)->set_value(dev, offset, value);
+	return dm_gpio_set_value(&desc, value);
 }
 
-const char *gpio_get_bank_info(struct device *dev, int *bit_count)
+const char *gpio_get_bank_info(struct udevice *dev, int *bit_count)
 {
 	struct gpio_dev_priv *priv;
 
 	/* Must be called on an active device */
-	priv = dev->uclass_priv;
+	priv = dev_get_uclass_priv(dev);
 	assert(priv);
 
 	*bit_count = priv->gpio_count;
 	return priv->bank_name;
 }
 
+static const char * const gpio_function[GPIOF_COUNT] = {
+	"input",
+	"output",
+	"unused",
+	"unknown",
+	"func",
+};
+
+int get_function(struct udevice *dev, int offset, bool skip_unused,
+		 const char **namep)
+{
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct dm_gpio_ops *ops = gpio_get_ops(dev);
+
+	BUILD_BUG_ON(GPIOF_COUNT != ARRAY_SIZE(gpio_function));
+	if (!device_active(dev))
+		return -ENODEV;
+	if (offset < 0 || offset >= uc_priv->gpio_count)
+		return -EINVAL;
+	if (namep)
+		*namep = uc_priv->name[offset];
+	if (skip_unused && !uc_priv->name[offset])
+		return GPIOF_UNUSED;
+	if (ops->get_function) {
+		int ret;
+
+		ret = ops->get_function(dev, offset);
+		if (ret < 0)
+			return ret;
+		if (ret >= ARRAY_SIZE(gpio_function))
+			return -ENODATA;
+		return ret;
+	}
+
+	return GPIOF_UNKNOWN;
+}
+
+int gpio_get_function(struct udevice *dev, int offset, const char **namep)
+{
+	return get_function(dev, offset, true, namep);
+}
+
+int gpio_get_raw_function(struct udevice *dev, int offset, const char **namep)
+{
+	return get_function(dev, offset, false, namep);
+}
+
+int gpio_get_status(struct udevice *dev, int offset, char *buf, int buffsize)
+{
+	struct dm_gpio_ops *ops = gpio_get_ops(dev);
+	struct gpio_dev_priv *priv;
+	char *str = buf;
+	int func;
+	int ret;
+	int len;
+
+	BUILD_BUG_ON(GPIOF_COUNT != ARRAY_SIZE(gpio_function));
+
+	*buf = 0;
+	priv = dev_get_uclass_priv(dev);
+	ret = gpio_get_raw_function(dev, offset, NULL);
+	if (ret < 0)
+		return ret;
+	func = ret;
+	len = snprintf(str, buffsize, "%s%d: %s",
+		       priv->bank_name ? priv->bank_name : "",
+		       offset, gpio_function[func]);
+	if (func == GPIOF_INPUT || func == GPIOF_OUTPUT ||
+	    func == GPIOF_UNUSED) {
+		const char *label;
+		bool used;
+
+		ret = ops->get_value(dev, offset);
+		if (ret < 0)
+			return ret;
+		used = gpio_get_function(dev, offset, &label) != GPIOF_UNUSED;
+		snprintf(str + len, buffsize - len, ": %d [%c]%s%s",
+			 ret,
+			 used ? 'x' : ' ',
+			 used ? " " : "",
+			 label ? label : "");
+	}
+
+	return 0;
+}
+
+int gpio_claim_vector(const int *gpio_num_array, const char *fmt)
+{
+	int i, ret;
+	int gpio;
+
+	for (i = 0; i < 32; i++) {
+		gpio = gpio_num_array[i];
+		if (gpio == -1)
+			break;
+		ret = gpio_requestf(gpio, fmt, i);
+		if (ret)
+			goto err;
+		ret = gpio_direction_input(gpio);
+		if (ret) {
+			gpio_free(gpio);
+			goto err;
+		}
+	}
+
+	return 0;
+err:
+	for (i--; i >= 0; i--)
+		gpio_free(gpio_num_array[i]);
+
+	return ret;
+}
+
+/*
+ * get a number comprised of multiple GPIO values. gpio_num_array points to
+ * the array of gpio pin numbers to scan, terminated by -1.
+ */
+int gpio_get_values_as_int(const int *gpio_list)
+{
+	int gpio;
+	unsigned bitmask = 1;
+	unsigned vector = 0;
+	int ret;
+
+	while (bitmask &&
+	       ((gpio = *gpio_list++) != -1)) {
+		ret = gpio_get_value(gpio);
+		if (ret < 0)
+			return ret;
+		else if (ret)
+			vector |= bitmask;
+		bitmask <<= 1;
+	}
+
+	return vector;
+}
+
+static int _gpio_request_by_name_nodev(const void *blob, int node,
+				       const char *list_name, int index,
+				       struct gpio_desc *desc, int flags,
+				       bool add_index)
+{
+	struct fdtdec_phandle_args args;
+	int ret;
+
+	desc->dev = NULL;
+	desc->offset = 0;
+	ret = fdtdec_parse_phandle_with_args(blob, node, list_name,
+					     "#gpio-cells", 0, index, &args);
+	if (ret) {
+		debug("%s: fdtdec_parse_phandle_with_args failed\n", __func__);
+		goto err;
+	}
+
+	ret = uclass_get_device_by_of_offset(UCLASS_GPIO, args.node,
+					     &desc->dev);
+	if (ret) {
+		debug("%s: uclass_get_device_by_of_offset failed\n", __func__);
+		goto err;
+	}
+	ret = gpio_find_and_xlate(desc, &args);
+	if (ret) {
+		debug("%s: gpio_find_and_xlate failed\n", __func__);
+		goto err;
+	}
+	ret = dm_gpio_requestf(desc, add_index ? "%s.%s%d" : "%s.%s",
+			       fdt_get_name(blob, node, NULL),
+			       list_name, index);
+	if (ret) {
+		debug("%s: dm_gpio_requestf failed\n", __func__);
+		goto err;
+	}
+	ret = dm_gpio_set_dir_flags(desc, flags | desc->flags);
+	if (ret) {
+		debug("%s: dm_gpio_set_dir failed\n", __func__);
+		goto err;
+	}
+
+	return 0;
+err:
+	debug("%s: Node '%s', property '%s', failed to request GPIO index %d: %d\n",
+	      __func__, fdt_get_name(blob, node, NULL), list_name, index, ret);
+	return ret;
+}
+
+int gpio_request_by_name_nodev(const void *blob, int node,
+			       const char *list_name, int index,
+			       struct gpio_desc *desc, int flags)
+{
+	return _gpio_request_by_name_nodev(blob, node, list_name, index, desc,
+					   flags, index > 0);
+}
+
+int gpio_request_by_name(struct udevice *dev,  const char *list_name, int index,
+			 struct gpio_desc *desc, int flags)
+{
+	/*
+	 * This isn't ideal since we don't use dev->name in the debug()
+	 * calls in gpio_request_by_name(), but we can do this until
+	 * gpio_request_by_name_nodev() can be dropped.
+	 */
+	return gpio_request_by_name_nodev(gd->fdt_blob, dev->of_offset,
+					  list_name, index, desc, flags);
+}
+
+int gpio_request_list_by_name_nodev(const void *blob, int node,
+				    const char *list_name,
+				    struct gpio_desc *desc, int max_count,
+				    int flags)
+{
+	int count;
+	int ret;
+
+	for (count = 0; count < max_count; count++) {
+		ret = _gpio_request_by_name_nodev(blob, node, list_name, count,
+						  &desc[count], flags, true);
+		if (ret == -ENOENT)
+			break;
+		else if (ret)
+			goto err;
+	}
+
+	/* We ran out of GPIOs in the list */
+	return count;
+
+err:
+	gpio_free_list_nodev(desc, count - 1);
+
+	return ret;
+}
+
+int gpio_request_list_by_name(struct udevice *dev, const char *list_name,
+			      struct gpio_desc *desc, int max_count,
+			      int flags)
+{
+	/*
+	 * This isn't ideal since we don't use dev->name in the debug()
+	 * calls in gpio_request_by_name(), but we can do this until
+	 * gpio_request_list_by_name_nodev() can be dropped.
+	 */
+	return gpio_request_list_by_name_nodev(gd->fdt_blob, dev->of_offset,
+					       list_name, desc, max_count,
+					       flags);
+}
+
+int gpio_get_list_count(struct udevice *dev, const char *list_name)
+{
+	int ret;
+
+	ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, dev->of_offset,
+					     list_name, "#gpio-cells", 0, -1,
+					     NULL);
+	if (ret) {
+		debug("%s: Node '%s', property '%s', GPIO count failed: %d\n",
+		      __func__, dev->name, list_name, ret);
+	}
+
+	return ret;
+}
+
+int dm_gpio_free(struct udevice *dev, struct gpio_desc *desc)
+{
+	/* For now, we don't do any checking of dev */
+	return _dm_gpio_free(desc->dev, desc->offset);
+}
+
+int gpio_free_list(struct udevice *dev, struct gpio_desc *desc, int count)
+{
+	int i;
+
+	/* For now, we don't do any checking of dev */
+	for (i = 0; i < count; i++)
+		dm_gpio_free(dev, &desc[i]);
+
+	return 0;
+}
+
+int gpio_free_list_nodev(struct gpio_desc *desc, int count)
+{
+	return gpio_free_list(NULL, desc, count);
+}
+
 /* We need to renumber the GPIOs when any driver is probed/removed */
-static int gpio_renumber(void)
+static int gpio_renumber(struct udevice *removed_dev)
 {
 	struct gpio_dev_priv *uc_priv;
-	struct device *dev;
+	struct udevice *dev;
 	struct uclass *uc;
 	unsigned base;
 	int ret;
@@ -237,8 +729,8 @@ static int gpio_renumber(void)
 	/* Ensure that we have a base for each bank */
 	base = 0;
 	uclass_foreach_dev(dev, uc) {
-		if (device_active(dev)) {
-			uc_priv = dev->uclass_priv;
+		if (device_active(dev) && dev != removed_dev) {
+			uc_priv = dev_get_uclass_priv(dev);
 			uc_priv->gpio_base = base;
 			base += uc_priv->gpio_count;
 		}
@@ -247,19 +739,47 @@ static int gpio_renumber(void)
 	return 0;
 }
 
-static int gpio_post_probe(struct device *dev)
+int gpio_get_number(struct gpio_desc *desc)
 {
-	return gpio_renumber();
+	struct udevice *dev = desc->dev;
+	struct gpio_dev_priv *uc_priv;
+
+	if (!dev)
+		return -1;
+	uc_priv = dev->uclass_priv;
+
+	return uc_priv->gpio_base + desc->offset;
 }
 
-static int gpio_pre_remove(struct device *dev)
+static int gpio_post_probe(struct udevice *dev)
 {
-	return gpio_renumber();
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+	uc_priv->name = calloc(uc_priv->gpio_count, sizeof(char *));
+	if (!uc_priv->name)
+		return -ENOMEM;
+
+	return gpio_renumber(NULL);
+}
+
+static int gpio_pre_remove(struct udevice *dev)
+{
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	int i;
+
+	for (i = 0; i < uc_priv->gpio_count; i++) {
+		if (uc_priv->name[i])
+			free(uc_priv->name[i]);
+	}
+	free(uc_priv->name);
+
+	return gpio_renumber(dev);
 }
 
 UCLASS_DRIVER(gpio) = {
 	.id		= UCLASS_GPIO,
 	.name		= "gpio",
+	.flags		= DM_UC_FLAG_SEQ_ALIAS,
 	.post_probe	= gpio_post_probe,
 	.pre_remove	= gpio_pre_remove,
 	.per_device_auto_alloc_size = sizeof(struct gpio_dev_priv),