LXR linux/drivers/gpio/gpiolib-devprop.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Device property helpers for GPIO chips.
   4 *
   5 * Copyright (C) 2016, Intel Corporation
   6 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
   7 */
   8
   9#include <linux/property.h>
  10#include <linux/slab.h>
  11#include <linux/gpio/consumer.h>
  12#include <linux/gpio/driver.h>
  13#include <linux/export.h>
  14
  15#include "gpiolib.h"
  16
  17/**
  18 * devprop_gpiochip_set_names - Set GPIO line names using device properties
  19 * @chip: GPIO chip whose lines should be named, if possible
  20 * @fwnode: Property Node containing the gpio-line-names property
  21 *
  22 * Looks for device property "gpio-line-names" and if it exists assigns
  23 * GPIO line names for the chip. The memory allocated for the assigned
  24 * names belong to the underlying firmware node and should not be released
  25 * by the caller.
  26 */
  27void devprop_gpiochip_set_names(struct gpio_chip *chip,
  28                                const struct fwnode_handle *fwnode)
  29{
  30        struct gpio_device *gdev = chip->gpiodev;
  31        const char **names;
  32        int ret, i;
  33        int count;
  34
  35        count = fwnode_property_read_string_array(fwnode, "gpio-line-names",
  36                                                  NULL, 0);
  37        if (count < 0)
  38                return;
  39
  40        if (count > gdev->ngpio)
  41                count = gdev->ngpio;
  42
  43        names = kcalloc(count, sizeof(*names), GFP_KERNEL);
  44        if (!names)
  45                return;
  46
  47        ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
  48                                                names, count);
  49        if (ret < 0) {
  50                dev_warn(&gdev->dev, "failed to read GPIO line names\n");
  51                kfree(names);
  52                return;
  53        }
  54
  55        for (i = 0; i < count; i++)
  56                gdev->descs[i].name = names[i];
  57
  58        kfree(names);
  59}
  60EXPORT_SYMBOL_GPL(devprop_gpiochip_set_names);
  61