RE: [PATCH] blackfin: bfin_reset_controller() busy flag appears cleared when it is not

From: Zhang, Sonic
Date: Thu Apr 10 2008 - 03:34:45 EST


Acked-by: Sonic Zhang <sonic.zhang@xxxxxxxxxx>

-----Original Message-----
From: Roel Kluin [mailto:12o3l@xxxxxxxxxx]
Sent: Wednesday, April 09, 2008 5:43 PM
To: sonic.zhang@xxxxxxxxxx
Cc: uclinux-dist-devel@xxxxxxxxxxxxxxxxxxxx; lkml
Subject: [PATCH] blackfin: bfin_reset_controller() busy flag appears
cleared when it is not

When count reaches 0 the postfix decrement still subtracts (to -1), so
bfin_reset_controller() returns as if the busy flag was cleared while it
was not.

Signed-off-by: Roel Kluin <12o3l@xxxxxxxxxx>
---
diff --git a/drivers/ata/pata_bf54x.c b/drivers/ata/pata_bf54x.c index
7f87f10..4208c49 100644
--- a/drivers/ata/pata_bf54x.c
+++ b/drivers/ata/pata_bf54x.c
@@ -1442,15 +1442,15 @@ static int bfin_reset_controller(struct ata_host
*host)
ATAPI_SET_CONTROL(base, ATAPI_GET_CONTROL(base) & ~DEV_RST);
msleep(2);

/* Wait on Busy flag to clear */
count = 10000000;
do {
status = read_atapi_register(base, ATA_REG_STATUS);
- } while (count-- && (status & ATA_BUSY));
+ } while (--count && (status & ATA_BUSY));

/* Enable only ATAPI Device interrupt */
ATAPI_SET_INT_MASK(base, 1);
SSYNC();

return (!count);
}
--
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