linux/drivers/of/of_net.c
Petr Štetiar 3ee9ae74ba of_net: Fix missing of_find_device_by_node ref count drop
of_find_device_by_node takes a reference to the embedded struct device
which needs to be dropped after use.

Fixes: d01f449c00 ("of_net: add NVMEM support to of_get_mac_address")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-13 08:52:37 -07:00

117 lines
3.2 KiB
C

/*
* OF helpers for network devices.
*
* This file is released under the GPLv2
*
* Initially copied out of arch/powerpc/kernel/prom_parse.c
*/
#include <linux/etherdevice.h>
#include <linux/kernel.h>
#include <linux/of_net.h>
#include <linux/of_platform.h>
#include <linux/phy.h>
#include <linux/export.h>
#include <linux/device.h>
/**
* of_get_phy_mode - Get phy mode for given device_node
* @np: Pointer to the given device_node
*
* The function gets phy interface string from property 'phy-mode' or
* 'phy-connection-type', and return its index in phy_modes table, or errno in
* error case.
*/
int of_get_phy_mode(struct device_node *np)
{
const char *pm;
int err, i;
err = of_property_read_string(np, "phy-mode", &pm);
if (err < 0)
err = of_property_read_string(np, "phy-connection-type", &pm);
if (err < 0)
return err;
for (i = 0; i < PHY_INTERFACE_MODE_MAX; i++)
if (!strcasecmp(pm, phy_modes(i)))
return i;
return -ENODEV;
}
EXPORT_SYMBOL_GPL(of_get_phy_mode);
static const void *of_get_mac_addr(struct device_node *np, const char *name)
{
struct property *pp = of_find_property(np, name, NULL);
if (pp && pp->length == ETH_ALEN && is_valid_ether_addr(pp->value))
return pp->value;
return NULL;
}
static const void *of_get_mac_addr_nvmem(struct device_node *np)
{
int ret;
const void *mac;
u8 nvmem_mac[ETH_ALEN];
struct platform_device *pdev = of_find_device_by_node(np);
if (!pdev)
return ERR_PTR(-ENODEV);
ret = nvmem_get_mac_address(&pdev->dev, &nvmem_mac);
if (ret) {
put_device(&pdev->dev);
return ERR_PTR(ret);
}
mac = devm_kmemdup(&pdev->dev, nvmem_mac, ETH_ALEN, GFP_KERNEL);
put_device(&pdev->dev);
if (!mac)
return ERR_PTR(-ENOMEM);
return mac;
}
/**
* Search the device tree for the best MAC address to use. 'mac-address' is
* checked first, because that is supposed to contain to "most recent" MAC
* address. If that isn't set, then 'local-mac-address' is checked next,
* because that is the default address. If that isn't set, then the obsolete
* 'address' is checked, just in case we're using an old device tree. If any
* of the above isn't set, then try to get MAC address from nvmem cell named
* 'mac-address'.
*
* Note that the 'address' property is supposed to contain a virtual address of
* the register set, but some DTS files have redefined that property to be the
* MAC address.
*
* All-zero MAC addresses are rejected, because those could be properties that
* exist in the device tree, but were not set by U-Boot. For example, the
* DTS could define 'mac-address' and 'local-mac-address', with zero MAC
* addresses. Some older U-Boots only initialized 'local-mac-address'. In
* this case, the real MAC is in 'local-mac-address', and 'mac-address' exists
* but is all zeros.
*
* Return: Will be a valid pointer on success and ERR_PTR in case of error.
*/
const void *of_get_mac_address(struct device_node *np)
{
const void *addr;
addr = of_get_mac_addr(np, "mac-address");
if (addr)
return addr;
addr = of_get_mac_addr(np, "local-mac-address");
if (addr)
return addr;
addr = of_get_mac_addr(np, "address");
if (addr)
return addr;
return of_get_mac_addr_nvmem(np);
}
EXPORT_SYMBOL(of_get_mac_address);