linux/drivers/mfd/wm831x-spi.c
Gustavo A. R. Silva 7b55033fbe mfd: wm831x-spi: Add NULL check before pointer dereference
Add NULL check before dereferencing pointer of_id in order to avoid
a potential NULL pointer dereference.

Addresses-Coverity-ID: 1408830
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2017-07-06 08:29:11 +01:00

145 lines
3.3 KiB
C

/*
* wm831x-spi.c -- SPI access for Wolfson WM831x PMICs
*
* Copyright 2009,2010 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pm.h>
#include <linux/spi/spi.h>
#include <linux/regmap.h>
#include <linux/err.h>
#include <linux/mfd/wm831x/core.h>
static int wm831x_spi_probe(struct spi_device *spi)
{
struct wm831x_pdata *pdata = dev_get_platdata(&spi->dev);
const struct spi_device_id *id = spi_get_device_id(spi);
const struct of_device_id *of_id;
struct wm831x *wm831x;
enum wm831x_parent type;
int ret;
if (spi->dev.of_node) {
of_id = of_match_device(wm831x_of_match, &spi->dev);
if (!of_id) {
dev_err(&spi->dev, "Failed to match device\n");
return -ENODEV;
}
type = (enum wm831x_parent)of_id->data;
} else {
type = (enum wm831x_parent)id->driver_data;
}
wm831x = devm_kzalloc(&spi->dev, sizeof(struct wm831x), GFP_KERNEL);
if (wm831x == NULL)
return -ENOMEM;
spi->mode = SPI_MODE_0;
spi_set_drvdata(spi, wm831x);
wm831x->dev = &spi->dev;
wm831x->type = type;
wm831x->regmap = devm_regmap_init_spi(spi, &wm831x_regmap_config);
if (IS_ERR(wm831x->regmap)) {
ret = PTR_ERR(wm831x->regmap);
dev_err(wm831x->dev, "Failed to allocate register map: %d\n",
ret);
return ret;
}
if (pdata)
memcpy(&wm831x->pdata, pdata, sizeof(*pdata));
return wm831x_device_init(wm831x, spi->irq);
}
static int wm831x_spi_remove(struct spi_device *spi)
{
struct wm831x *wm831x = spi_get_drvdata(spi);
wm831x_device_exit(wm831x);
return 0;
}
static int wm831x_spi_suspend(struct device *dev)
{
struct wm831x *wm831x = dev_get_drvdata(dev);
return wm831x_device_suspend(wm831x);
}
static int wm831x_spi_poweroff(struct device *dev)
{
struct wm831x *wm831x = dev_get_drvdata(dev);
wm831x_device_shutdown(wm831x);
return 0;
}
static const struct dev_pm_ops wm831x_spi_pm = {
.freeze = wm831x_spi_suspend,
.suspend = wm831x_spi_suspend,
.poweroff = wm831x_spi_poweroff,
};
static const struct spi_device_id wm831x_spi_ids[] = {
{ "wm8310", WM8310 },
{ "wm8311", WM8311 },
{ "wm8312", WM8312 },
{ "wm8320", WM8320 },
{ "wm8321", WM8321 },
{ "wm8325", WM8325 },
{ "wm8326", WM8326 },
{ },
};
MODULE_DEVICE_TABLE(spi, wm831x_spi_ids);
static struct spi_driver wm831x_spi_driver = {
.driver = {
.name = "wm831x",
.pm = &wm831x_spi_pm,
.of_match_table = of_match_ptr(wm831x_of_match),
},
.id_table = wm831x_spi_ids,
.probe = wm831x_spi_probe,
.remove = wm831x_spi_remove,
};
static int __init wm831x_spi_init(void)
{
int ret;
ret = spi_register_driver(&wm831x_spi_driver);
if (ret != 0)
pr_err("Failed to register WM831x SPI driver: %d\n", ret);
return 0;
}
subsys_initcall(wm831x_spi_init);
static void __exit wm831x_spi_exit(void)
{
spi_unregister_driver(&wm831x_spi_driver);
}
module_exit(wm831x_spi_exit);
MODULE_DESCRIPTION("SPI support for WM831x/2x AudioPlus PMICs");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mark Brown");