From: Tejun Heo Date: Mon, 15 May 2006 11:57:46 +0000 (+0900) Subject: [PATCH] libata: implement new SCR handling and port on/offline functions X-Git-Tag: v2.6.18-rc1~1079^2~98^2~41 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=34bf21704c848fe00c516d1c8f163db08b70b137;p=pandora-kernel.git [PATCH] libata: implement new SCR handling and port on/offline functions Implement ata_scr_{valid|read|write|write_flush}() and ata_port_{online|offline}(). These functions replace scr_{read|write}() and sata_dev_present(). Major difference between between the new SCR functions and the old ones is that the new ones have a way to signal error to the caller. This makes handling SCR-available and SCR-unavailable cases in the same path easier. Also, it eases later PM implementation where SCR access can fail due to various reasons. ata_port_{online|offline}() functions return 1 only when they are affirmitive of the condition. e.g. if SCR is unaccessible or presence cannot be determined for other reasons, these functions return 0. So, ata_port_online() != !ata_port_offline(). This distinction is useful in many exception handling cases. Signed-off-by: Tejun Heo --- Reading git-diff-tree failed