From: Rafał Miłecki rafal@milecki.pl
stable inclusion from linux-4.19.207 commit e24ffdb604179a057e9be5c9a8ed68b90a28eee5
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[ Upstream commit cdb067d31c0fe4cce98b9d15f1f2ef525acaa094 ]
It isn't true that CPU port is always the last one. Switches BCM5301x have 9 ports (port 6 being inactive) and they use port 5 as CPU by default (depending on design some other may be CPU ports too).
A more reliable way of determining number of ports is to check for the last set bit in the "enabled_ports" bitfield.
This fixes b53 internal state, it will allow providing accurate info to the DSA and is required to fix BCM5301x support.
Fixes: 967dd82ffc52 ("net: dsa: b53: Add support for Broadcom RoboSwitch") Signed-off-by: Rafał Miłecki rafal@milecki.pl Reviewed-by: Florian Fainelli f.fainelli@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/net/dsa/b53/b53_common.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c index 7eaeab65d39f5..451121f47c89a 100644 --- a/drivers/net/dsa/b53/b53_common.c +++ b/drivers/net/dsa/b53/b53_common.c @@ -2135,9 +2135,8 @@ static int b53_switch_init(struct b53_device *dev) dev->cpu_port = 5; }
- /* cpu port is always last */ - dev->num_ports = dev->cpu_port + 1; dev->enabled_ports |= BIT(dev->cpu_port); + dev->num_ports = fls(dev->enabled_ports);
/* Include non standard CPU port built-in PHYs to be probed */ if (is539x(dev) || is531x5(dev)) {