drivers/extcon/of_extcon.c

   1 /*
   2  * OF helpers for External connector (extcon) framework
   3  *
   4  * Copyright (C) 2013 Texas Instruments, Inc.
   5  * Kishon Vijay Abraham I <kishon@ti.com>
   6  *
   7  * Copyright (C) 2013 Samsung Electronics
   8  * Chanwoo Choi <cw00.choi@samsung.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18 #include <linux/err.h>
  19 #include <linux/extcon.h>
  20 #include <linux/of.h>
  21 #include <linux/of_platform.h>
  22 #include <linux/extcon/of_extcon.h>
  23
  24 /*
  25  * of_extcon_get_extcon_dev - Get the name of extcon device from devicetree
  26  * @dev - instance to the given device
  27  * @index - index into list of extcon_dev
  28  *
  29  * return the instance of extcon device
  30  */
  31 struct extcon_dev *of_extcon_get_extcon_dev(struct device *dev, int index)
  32 {
  33         struct device_node *node;
  34         struct extcon_dev *edev;
  35         struct platform_device *extcon_parent_dev;
  36
  37         if (!dev->of_node) {
  38                 dev_dbg(dev, "device does not have a device node entry\n");
  39                 return ERR_PTR(-EINVAL);
  40         }
  41
  42         node = of_parse_phandle(dev->of_node, "extcon", index);
  43         if (!node) {
  44                 dev_dbg(dev, "failed to get phandle in %s node\n",
  45                         dev->of_node->full_name);
  46                 return ERR_PTR(-ENODEV);
  47         }
  48
  49         extcon_parent_dev = of_find_device_by_node(node);
  50         if (!extcon_parent_dev) {
  51                 dev_dbg(dev, "unable to find device by node\n");
  52                 return ERR_PTR(-EPROBE_DEFER);
  53         }
  54
  55         edev = extcon_get_extcon_dev(dev_name(&extcon_parent_dev->dev));
  56         if (!edev) {
  57                 dev_dbg(dev, "unable to get extcon device : %s\n",
  58                                 dev_name(&extcon_parent_dev->dev));
  59                 return ERR_PTR(-ENODEV);
  60         }
  61
  62         return edev;
  63 }
  64 EXPORT_SYMBOL_GPL(of_extcon_get_extcon_dev);