Hi Russell,

-----Original Message-----
From: Russell King <redacted> On Behalf Of Russell King (Oracle)
Sent: Tuesday, February 18, 2025 7:25 PM
To: netdev@vger.kernel.org
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Subject: [PATCH net-next 2/3] net: stmmac: remove useless priv->flow_ctrl

priv->flow_ctrl is only accessed by stmmac_main.c, and the only place
that it is read is in stmmac_mac_flow_ctrl(). This function is only called from
stmmac_mac_link_up() which always sets priv->flow_ctrl immediately before
calling this function.

Therefore, initialising this at probe time is ineffectual because it will always be
overwritten before it's read. As such, the "flow_ctrl"
module parameter has been useless for some time. Rather than remove the
module parameter, which would risk module load failure, change the
description to indicate that it is obsolete, and warn if it is set by userspace.

Moreover, storing the value in the stmmac_priv has no benefit as it's set and
then immediately read stmmac_mac_flow_ctrl(). Instead, pass it as a
parameter to this function..

Signed-off-by: Russell King (Oracle) <redacted>

Reviewed-by: Nobuhiro Iwamatsu <redacted>

Best regards,
  Nobuhiro