From cca6b5d4c4eb0f9b04ba8a48c196d386960a10cb Mon Sep 17 00:00:00 2001 From: =?utf8?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=utf8 Content-Transfer-Encoding: 8bit [ 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 Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- 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 820aed3e2352..9fff49229435 100644 --- a/drivers/net/dsa/b53/b53_common.c +++ b/drivers/net/dsa/b53/b53_common.c @@ -1843,9 +1843,8 @@ 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); dev->ports = devm_kzalloc(dev->dev, sizeof(struct b53_port) * dev->num_ports, -- 2.20.1