From 70934c7c99ad01778eef83e898df4c624e52492f Mon Sep 17 00:00:00 2001 From: "Russell King (Oracle)" Date: Thu, 24 Aug 2023 14:37:53 +0100 Subject: net: phylink: add phylink_limit_mac_speed() Add a function which can be used to limit the phylink MAC capabilities to an upper speed limit. Signed-off-by: Russell King (Oracle) Link: https://lore.kernel.org/r/E1qZAX3-005pTi-K1@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski --- drivers/net/phy/phylink.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'drivers/net') diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c index 160bce608c34..0d7354955d62 100644 --- a/drivers/net/phy/phylink.c +++ b/drivers/net/phy/phylink.c @@ -426,6 +426,24 @@ static struct { { MAC_10HD, SPEED_10, DUPLEX_HALF }, }; +/** + * phylink_limit_mac_speed - limit the phylink_config to a maximum speed + * @config: pointer to a &struct phylink_config + * @max_speed: maximum speed + * + * Mask off MAC capabilities for speeds higher than the @max_speed parameter. + * Any further motifications of config.mac_capabilities will override this. + */ +void phylink_limit_mac_speed(struct phylink_config *config, u32 max_speed) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(phylink_caps_params) && + phylink_caps_params[i].speed > max_speed; i++) + config->mac_capabilities &= ~phylink_caps_params[i].mask; +} +EXPORT_SYMBOL_GPL(phylink_limit_mac_speed); + /** * phylink_cap_from_speed_duplex - Get mac capability from speed/duplex * @speed: the speed to search for -- cgit