On 06/19/2018 09:09 AM, Bartosz Golaszewski wrote: > From: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> > > This patch reverts commit 3243ff2a05ec ("net: ethernet: davinci_emac: > Deduplicate bus_find_device() by name matching") and adds a comment > which should stop anyone from reintroducing the same "fix" in the future. > > We can't use bus_find_device_by_name() here because the device name is > not guaranteed to be 'davinci_mdio'. On some systems it can be > 'davinci_mdio.0' so we need to use strncmp() against the first part of > the string to correctly match it. > > Fixes: 3243ff2a05ec ("net: ethernet: davinci_emac: Deduplicate bus_find_device() by name matching") > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> > --- > drivers/net/ethernet/ti/davinci_emac.c | 15 +++++++++++++-- > 1 file changed, 13 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/ethernet/ti/davinci_emac.c b/drivers/net/ethernet/ti/davinci_emac.c > index 06d7c9e4dcda..a1a6445b5a7e 100644 > --- a/drivers/net/ethernet/ti/davinci_emac.c > +++ b/drivers/net/ethernet/ti/davinci_emac.c > @@ -1385,6 +1385,11 @@ static int emac_devioctl(struct net_device *ndev, struct ifreq *ifrq, int cmd) > return -EOPNOTSUPP; > } > > +static int match_first_device(struct device *dev, void *data) > +{ > + return !strncmp(dev_name(dev), "davinci_mdio", 12); const char *bus_name = "davinci_mdio"; return !strncmp(dev_name(dev), bus_name, strlen(bus_name)); Or even better yet, if you want to make sure this really is a PHY device that you are trying to match, you could try to use sscanf() with PHY_ID_FMT. -- Florian