netdev - Re: [PATCH] icplus: mdio_write(), remove unnecessary for loop

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Message-Id: <20111129.184758.1166451793914536662.davem@davemloft.net>
Date:	Tue, 29 Nov 2011 18:47:58 -0500 (EST)
From:	David Miller <davem@...emloft.net>
To:	patrick.kelle81@...il.com
Cc:	netdev@...r.kernel.org, romieu@...zoreil.com, sorbica@...lus.com.tw
Subject: Re: [PATCH] icplus: mdio_write(), remove unnecessary for loop

From: Patrick Kelle <patrick.kelle81@...il.com>
Date: Thu, 24 Nov 2011 16:39:05 +0100

> At this point the variable j is always set to 7 and the code within
> the loop has to run only once anyway.
> 
> Signed-off-by: Patrick Kelle <patrick.kelle81@...il.com>

You can simply this even further since p[7] is what is used here,
and this means len is one, the inner loop therefore executes only
once, and the p[7].field value is not used (it's zero in the table)
and the write to it is completely thrown away.

It all reduces to something like:

	ipg_write_phy_ctl(ioaddr, IPG_PC_MGMTCLK_LO | polarity);
	ipg_r8(PHY_CTRL);
	ipg_write_phy_ctl(ioaddr, IPG_PC_MGMTCLK_HI | polarity);

Which is just asserting the management clock low, then high, and
doing a PHY_CTRL read in between to force the write out, the read
data is not used at all.
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