From: Timo Teräs Date: Thu, 10 Jun 2010 00:31:48 +0000 (-0700) Subject: r8169: fix mdio_read and update mdio_write according to hw specs X-Git-Tag: firefly_0821_release~10186^2~915 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0bc4d2f86c7c6bf4bc8dab446e184744cdee51d0;p=firefly-linux-kernel-4.4.55.git r8169: fix mdio_read and update mdio_write according to hw specs [ Upstream commit 81a95f049962ec20a9aed888e676208b206f0f2e ] Realtek confirmed that a 20us delay is needed after mdio_read and mdio_write operations. Reduce the delay in mdio_write, and add it to mdio_read too. Also add a comment that the 20us is from hw specs. Signed-off-by: Timo Teräs Acked-by: Francois Romieu Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c index 3aafa535fa2a..62e784accf3b 100644 --- a/drivers/net/r8169.c +++ b/drivers/net/r8169.c @@ -558,10 +558,10 @@ static void mdio_write(void __iomem *ioaddr, int reg_addr, int value) udelay(25); } /* - * Some configurations require a small delay even after the write - * completed indication or the next write might fail. + * According to hardware specs a 20us delay is required after write + * complete indication, but before sending next command. */ - udelay(25); + udelay(20); } static int mdio_read(void __iomem *ioaddr, int reg_addr) @@ -581,6 +581,12 @@ static int mdio_read(void __iomem *ioaddr, int reg_addr) } udelay(25); } + /* + * According to hardware specs a 20us delay is required after read + * complete indication, but before sending next command. + */ + udelay(20); + return value; }