From: Alexander Kochetkov Date: Thu, 13 Nov 2014 01:26:20 +0000 (+0400) Subject: net/smsc911x: Fix delays in the PHY enable/disable routines X-Git-Tag: omap-for-v3.19/fixes-for-merge-window~119^2~3 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6ff53fd37175e35dc4f70b0e8f48b28338fbee29;p=pandora-kernel.git net/smsc911x: Fix delays in the PHY enable/disable routines Increased delay in the smsc911x_phy_disable_energy_detect (from 1ms to 2ms). Dropped delays in the smsc911x_phy_enable_energy_detect (100ms and 1ms). The patch affect SMSC LAN generation 4 chips with integrated PHY (LAN9221). I saw problems with soft reset due to wrong udelay timings. After I fixed udelay, I measured the time needed to bring integrated PHY from power-down to operational mode (the time beetween clearing EDPWRDOWN bit and soft reset complete event). I got 1ms (measured using ktime_get). The value is equal to the current value (1ms) used in the smsc911x_phy_disable_energy_detect. It is near the upper bound and in order to avoid rare soft reset faults it is doubled (2ms). I don't know official timing for bringing up integrated PHY as specs doesn't clarify this (or may be I didn't found). It looks safe to drop delays before and after setting EDPWRDOWN bit (enable PHY power-down mode). I didn't saw any regressions with the patch. The patch was reviewed by Steve Glendinning and Microchip Team. Signed-off-by: Alexander Kochetkov Acked-by: Steve Glendinning Signed-off-by: David S. Miller --- Reading git-diff-tree failed