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		dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d",
42			 count, gdev->ngpio);
43		count = gdev->ngpio;
44	}
45
46	names = kcalloc(count, sizeof(*names), GFP_KERNEL);
47	if (!names)
48		return;
49
50	ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
51						names, count);
52	if (ret < 0) {
53		dev_warn(&gdev->dev, "failed to read GPIO line names\n");
54		kfree(names);
55		return;
56	}
57
58	for (i = 0; i < count; i++)
59		gdev->descs[i].name = names[i];
60
61	kfree(names);
62}
63EXPORT_SYMBOL_GPL(devprop_gpiochip_set_names);