From: Rafał Miłecki rafal@milecki.pl
[ Upstream commit d12e1c4649883e8ca5e8ff341e1948b3b6313259 ]
Setting DSA_MAX_PORTS caused DSA to call b53 callbacks (e.g. b53_disable_port() during dsa_register_switch()) for invalid (non-existent) ports. That made b53 modify unrelated registers and is one of reasons for a broken BCM5301x support.
This problem exists for years but DSA_MAX_PORTS usage has changed few times. It seems the most accurate to reference commit dropping dsa_switch_alloc() in the Fixes tag.
Fixes: 7e99e3470172 ("net: dsa: remove dsa_switch_alloc helper") Signed-off-by: Rafał Miłecki rafal@milecki.pl Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/dsa/b53/b53_common.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c index dcf9d7e5ae14..5646eb8afe38 100644 --- a/drivers/net/dsa/b53/b53_common.c +++ b/drivers/net/dsa/b53/b53_common.c @@ -2615,6 +2615,8 @@ static int b53_switch_init(struct b53_device *dev) dev->enabled_ports |= BIT(dev->cpu_port); dev->num_ports = fls(dev->enabled_ports);
+ dev->ds->num_ports = min_t(unsigned int, dev->num_ports, DSA_MAX_PORTS); + /* Include non standard CPU port built-in PHYs to be probed */ if (is539x(dev) || is531x5(dev)) { for (i = 0; i < dev->num_ports; i++) { @@ -2659,7 +2661,6 @@ struct b53_device *b53_switch_alloc(struct device *base, return NULL;
ds->dev = base; - ds->num_ports = DSA_MAX_PORTS;
dev = devm_kzalloc(base, sizeof(*dev), GFP_KERNEL); if (!dev)