1/*
 2 * Device property helpers for GPIO chips.
 3 *
 4 * Copyright (C) 2016, Intel Corporation
 5 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
 6 *
 7 * This program is free software; you can redistribute it and/or modify
 8 * it under the terms of the GNU General Public License version 2 as
 9 * published by the Free Software Foundation.
10 */
11
12#include <linux/property.h>
13#include <linux/slab.h>
14#include <linux/gpio/consumer.h>
15#include <linux/gpio/driver.h>
16
17#include "gpiolib.h"
18
19/**
20 * devprop_gpiochip_set_names - Set GPIO line names using device properties
21 * @chip: GPIO chip whose lines should be named, if possible
22 * @fwnode: Property Node containing the gpio-line-names property
23 *
24 * Looks for device property "gpio-line-names" and if it exists assigns
25 * GPIO line names for the chip. The memory allocated for the assigned
26 * names belong to the underlying firmware node and should not be released
27 * by the caller.
28 */
29void devprop_gpiochip_set_names(struct gpio_chip *chip,
30				const struct fwnode_handle *fwnode)
31{
32	struct gpio_device *gdev = chip->gpiodev;
33	const char **names;
34	int ret, i;
35
36	ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
37						NULL, 0);
38	if (ret < 0)
39		return;
40
41	if (ret != gdev->ngpio) {
42		dev_warn(&gdev->dev,
43			 "names %d do not match number of GPIOs %d\n", ret,
44			 gdev->ngpio);
45		return;
46	}
47
48	names = kcalloc(gdev->ngpio, sizeof(*names), GFP_KERNEL);
49	if (!names)
50		return;
51
52	ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
53						names, gdev->ngpio);
54	if (ret < 0) {
55		dev_warn(&gdev->dev, "failed to read GPIO line names\n");
56		kfree(names);
57		return;
58	}
59
60	for (i = 0; i < gdev->ngpio; i++)
61		gdev->descs[i].name = names[i];
62
63	kfree(names);
64}