net: dsa: remove master santiy check

Because we probe the master ourselves (and fail if there is no master),
it is not possible that we don't have a master device.

There is one catch though: device removal. We don't support that. It
wasn't supported neither before this patch. Because the master device
was only set in .pre_probe(), if a device was removed master_dev was a
dangling pointer and transmitting a frame cause a panic. I don't see a
good solution without having some sort of notify machanism when a
udevice is removed.

Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc> [DSA unit tests]
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
This commit is contained in:
Michael Walle 2021-02-24 17:40:42 +01:00 committed by Priyanka Jain
parent 108157c468
commit 714555374f

View file

@ -69,11 +69,6 @@ static int dsa_port_start(struct udevice *pdev)
struct dsa_ops *ops = dsa_get_ops(dev);
int err;
if (!master) {
dev_err(pdev, "DSA master Ethernet device not found!\n");
return -EINVAL;
}
if (ops->port_enable) {
struct dsa_port_pdata *port_pdata;
@ -108,13 +103,7 @@ static void dsa_port_stop(struct udevice *pdev)
ops->port_disable(dev, priv->cpu_port, NULL);
}
/*
* stop master only if it's active, don't probe it otherwise.
* Under normal usage it would be active because we're using it, but
* during tear-down it may have been removed ahead of us.
*/
if (master && device_active(master))
eth_get_ops(master)->stop(master);
eth_get_ops(master)->stop(master);
}
/*
@ -133,9 +122,6 @@ static int dsa_port_send(struct udevice *pdev, void *packet, int length)
struct dsa_port_pdata *port_pdata;
int err;
if (!master)
return -EINVAL;
if (length + head + tail > PKTSIZE_ALIGN)
return -EINVAL;
@ -165,9 +151,6 @@ static int dsa_port_recv(struct udevice *pdev, int flags, uchar **packetp)
struct dsa_port_pdata *port_pdata;
int length, port_index, err;
if (!master)
return -EINVAL;
length = eth_get_ops(master)->recv(master, flags, packetp);
if (length <= 0)
return length;
@ -201,9 +184,6 @@ static int dsa_port_free_pkt(struct udevice *pdev, uchar *packet, int length)
struct udevice *master = dsa_get_master(dev);
struct dsa_priv *priv;
if (!master)
return -EINVAL;
priv = dev_get_uclass_priv(dev);
if (eth_get_ops(master)->free_pkt) {
/* return the original pointer and length to master Eth */
@ -284,6 +264,9 @@ static int dsa_port_probe(struct udevice *pdev)
/*
* Probe the master device. We depend on the master device for proper
* operation and we also need it for MAC inheritance below.
*
* TODO: we assume the master device is always there and doesn't get
* removed during runtime.
*/
ret = device_probe(master);
if (ret)