From: Lukasz Dorau Date: Mon, 14 Oct 2013 16:18:53 +0000 (+0200) Subject: libahci: fix turning on LEDs in ahci_start_port() X-Git-Tag: v3.12-rc7~28^2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fa070ee6dc70bcc19737a2406d741b089b3149d5;p=pandora-kernel.git libahci: fix turning on LEDs in ahci_start_port() If EM Transmit bit is busy during init ata_msleep() is called. It is wrong - msleep() should be used instead of ata_msleep(), because if EM Transmit bit is busy for one port, it will be busy for all other ports too, so using ata_msleep() causes wasting tries for another ports. The most common scenario looks like that now (six ports try to transmit a LED meaasege): - port #0 tries for the 1st time and succeeds - ports #1-5 try for the 1st time and sleeps - port #1 tries for the 2nd time and succeeds - ports #2-5 try for the 2nd time and sleeps - port #2 tries for the 3rd time and succeeds - ports #3-5 try for the 3rd time and sleeps - port #3 tries for the 4th time and succeeds - ports #4-5 try for the 4th time and sleeps - port #4 tries for the 5th time and succeeds - port #5 tries for the 5th time and sleeps At this moment port #5 wasted all its five tries and failed to initialize. Because there are only 5 (EM_MAX_RETRY) tries available usually only five ports succeed to initialize. The sixth port and next ones usually will fail. If msleep() is used instead of ata_msleep() the first port succeeds to initialize in the first try and next ones usually succeed to initialize in the second try. tj: updated comment Signed-off-by: Lukasz Dorau Signed-off-by: Tejun Heo --- Reading git-diff-tree failed