From cdb067d31c0fe4cce98b9d15f1f2ef525acaa094 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= Date: Thu, 2 Sep 2021 10:30:50 +0200 Subject: [PATCH] net: dsa: b53: Fix calculating number of switch ports MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/dsa/b53/b53_common.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/net/dsa/b53/b53_common.c +++ b/drivers/net/dsa/b53/b53_common.c @@ -2584,9 +2584,8 @@ static int b53_switch_init(struct b53_de 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)) {