linux/drivers/gpio/gpiolib-devprop.c
Stephen Boyd 9784c9963f gpiolib: devprop: Warn if gpio-line-names is too long
Some DT authors (including myself) have messed up the length of
gpio-line-names and made it longer than it should be. Add a warning here
so that developers can figure out that they've messed up their DT and
should fix it.

Cc: Alexandru M Stan <amstan@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-04-24 09:10:01 +02:00

64 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Device property helpers for GPIO chips.
*
* Copyright (C) 2016, Intel Corporation
* Author: Mika Westerberg <mika.westerberg@linux.intel.com>
*/
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/gpio/consumer.h>
#include <linux/gpio/driver.h>
#include <linux/export.h>
#include "gpiolib.h"
/**
* devprop_gpiochip_set_names - Set GPIO line names using device properties
* @chip: GPIO chip whose lines should be named, if possible
* @fwnode: Property Node containing the gpio-line-names property
*
* Looks for device property "gpio-line-names" and if it exists assigns
* GPIO line names for the chip. The memory allocated for the assigned
* names belong to the underlying firmware node and should not be released
* by the caller.
*/
void devprop_gpiochip_set_names(struct gpio_chip *chip,
const struct fwnode_handle *fwnode)
{
struct gpio_device *gdev = chip->gpiodev;
const char **names;
int ret, i;
int count;
count = fwnode_property_read_string_array(fwnode, "gpio-line-names",
NULL, 0);
if (count < 0)
return;
if (count > gdev->ngpio) {
dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d",
count, gdev->ngpio);
count = gdev->ngpio;
}
names = kcalloc(count, sizeof(*names), GFP_KERNEL);
if (!names)
return;
ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
names, count);
if (ret < 0) {
dev_warn(&gdev->dev, "failed to read GPIO line names\n");
kfree(names);
return;
}
for (i = 0; i < count; i++)
gdev->descs[i].name = names[i];
kfree(names);
}
EXPORT_SYMBOL_GPL(devprop_gpiochip_set_names);