linux/drivers/of/of_net.c
Andrew Lunn 0c65b2b90d net: of_get_phy_mode: Change API to solve int/unit warnings
Before this change of_get_phy_mode() returned an enum,
phy_interface_t. On error, -ENODEV etc, is returned. If the result of
the function is stored in a variable of type phy_interface_t, and the
compiler has decided to represent this as an unsigned int, comparision
with -ENODEV etc, is a signed vs unsigned comparision.

Fix this problem by changing the API. Make the function return an
error, or 0 on success, and pass a pointer, of type phy_interface_t,
where the phy mode should be stored.

v2:
Return with *interface set to PHY_INTERFACE_MODE_NA on error.
Add error checks to all users of of_get_phy_mode()
Fixup a few reverse christmas tree errors
Fixup a few slightly malformed reverse christmas trees

v3:
Fix 0-day reported errors.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-04 11:21:25 -08:00

122 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* OF helpers for network devices.
*
* 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
* @interface: Pointer to the result
*
* The function gets phy interface string from property 'phy-mode' or
* 'phy-connection-type'. The index in phy_modes table is set in
* interface and 0 returned. In case of error interface is set to
* PHY_INTERFACE_MODE_NA and an errno is returned, e.g. -ENODEV.
*/
int of_get_phy_mode(struct device_node *np, phy_interface_t *interface)
{
const char *pm;
int err, i;
*interface = PHY_INTERFACE_MODE_NA;
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))) {
*interface = i;
return 0;
}
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);