本文共 717 字，大约阅读时间需要 2 分钟。

在配置CONFIG_OF_GPIO下作用：

int of_gpiochip_add(struct gpio_chip *chip){ int status;  if ((!chip->of_node) && (chip->parent))  chip->of_node = chip->parent->of_node;  if (!chip->of_node)  return 0;  if (!chip->of_xlate) {  chip->of_gpio_n_cells = 2;  chip->of_xlate = of_gpio_simple_xlate; }  if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)  return -EINVAL;  status = of_gpiochip_add_pin_range(chip); if (status)  return status;  /* If the chip defines names itself, these take precedence */ if (!chip->names)  of_gpiochip_set_names(chip);  of_node_get(chip->of_node);  return of_gpiochip_scan_gpios(chip);} void of_gpiochip_remove(struct gpio_chip *chip){ gpiochip_remove_pin_ranges(chip); of_node_put(chip->of_node);}

转载地址：http://dgqti.baihongyu.com/