From 0ceb47987d31f8529c60f1e802e0523fcde9492c Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Sun, 29 Jul 2007 22:22:04 +0300 Subject: [PATCH] [SCSI] aha152x: preliminary fixes and some comments hunk by hunk: - CHECK_CONDITION is what happens to cmnd->status >> 1 or after status_byte() macro. But here it is used directly on status which means 0x1 which is an undefined bit in the standard. And is a status that will never return from a target. - in busfree_run at the DONE_SC phase we have 3 distinct operation: 1-if(DONE_SC->SCp.phase & check_condition) The REQUEST_SENSE command return. - Restore original command - Than continue to operation 3. 2-if(DONE_SC->SCp.Status==SAM_STAT_CHECK_CONDITION) A regular command returned with a status. - Internally re-Q a REQUEST_SENSE. - Do not do operation 3. 3- - Complete the command and return it to scsi-ml So the 0x2 in both these operations (1,2) means the scsi check-condition status, hence SAM_STAT_CHECK_CONDITION - Here the code asks about !(DONE_SC->SCp.Status & not_issued) but "not_issued" is an enum belonging to the "phase" member and not to the Status returned from target. The reason this works is because not_issued==1 and Also CHECK_CONDITION==1 (remember from hunk 1). So actually the code was asking !(DONE_SC->SCp.Status & CHECK_CONDITION). Which means "Has the status been read from target yet?" Staus is read at status_run(). "not_issued" is cleared in seldo_run() which is usually earlier than status_run(). So this patch does nothing as far as assembly is concerned but it does let the reader understand what is going on. Signed-off-by: Boaz Harrosh Signed-off-by: James Bottomley --- drivers/scsi/aha152x.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/aha152x.c b/drivers/scsi/aha152x.c index c841f11f4e32..dc7d84bae96b 100644 --- a/drivers/scsi/aha152x.c +++ b/drivers/scsi/aha152x.c @@ -986,7 +986,7 @@ static int aha152x_internal_queue(Scsi_Cmnd *SCpnt, struct completion *complete, SCpnt->scsi_done = done; SCpnt->resid = SCpnt->request_bufflen; SCpnt->SCp.phase = not_issued | phase; - SCpnt->SCp.Status = CHECK_CONDITION; + SCpnt->SCp.Status = 0x1; /* Ilegal status by SCSI standard */ SCpnt->SCp.Message = 0; SCpnt->SCp.have_data_in = 0; SCpnt->SCp.sent_command = 0; @@ -1574,12 +1574,12 @@ static void busfree_run(struct Scsi_Host *shpnt) cmd->use_sg = sc->use_sg; cmd->cmd_len = sc->cmd_len; - cmd->SCp.Status = 0x02; + cmd->SCp.Status = SAM_STAT_CHECK_CONDITION; HOSTDATA(shpnt)->commands--; if (!HOSTDATA(shpnt)->commands) SETPORT(PORTA, 0); /* turn led off */ - } else if(DONE_SC->SCp.Status==0x02) { + } else if(DONE_SC->SCp.Status==SAM_STAT_CHECK_CONDITION) { #if defined(AHA152X_STAT) HOSTDATA(shpnt)->busfree_with_check_condition++; #endif @@ -1587,7 +1587,7 @@ static void busfree_run(struct Scsi_Host *shpnt) DPRINTK(debug_eh, ERR_LEAD "CHECK CONDITION found\n", CMDINFO(DONE_SC)); #endif - if(!(DONE_SC->SCp.Status & not_issued)) { + if(!(DONE_SC->SCp.phase & not_issued)) { Scsi_Cmnd *ptr = DONE_SC; DONE_SC=NULL; #if 0