+/**
+ * Convert a GPIO name to its descriptor
+ */
+static struct gpio_desc *gpio_name_to_desc(const char * const name)
+{
+ struct gpio_chip *chip;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gpio_lock, flags);
+
+ list_for_each_entry(chip, &gpio_chips, list) {
+ int i;
+
+ for (i = 0; i != chip->ngpio; ++i) {
+ struct gpio_desc *gpio = &chip->desc[i];
+
+ if (!gpio->name)
+ continue;
+
+ if (!strcmp(gpio->name, name)) {
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ return gpio;
+ }
+ }
+ }
+
+ spin_unlock_irqrestore(&gpio_lock, flags);
+
+ return NULL;
+}
+
+/*
+ * Takes the names from gc->names and checks if they are all unique. If they
+ * are, they are assigned to their gpio descriptors.
+ *
+ * Returns -EEXIST if one of the names is already used for a different GPIO.
+ */
+static int gpiochip_set_desc_names(struct gpio_chip *gc)
+{
+ int i;
+
+ if (!gc->names)
+ return 0;
+
+ /* First check all names if they are unique */
+ for (i = 0; i != gc->ngpio; ++i) {
+ struct gpio_desc *gpio;
+
+ gpio = gpio_name_to_desc(gc->names[i]);
+ if (gpio)
+ dev_warn(gc->dev, "Detected name collision for "
+ "GPIO name '%s'\n",
+ gc->names[i]);
+ }
+
+ /* Then add all names to the GPIO descriptors */
+ for (i = 0; i != gc->ngpio; ++i)
+ gc->desc[i].name = gc->names[i];
+
+ return 0;
+}
+