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

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

[Roel Kluin]

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@tiscali.nl>
---
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);
 }

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

[Zhang, Sonic]

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

-----Original Message-----
From: Roel Kluin [mailto:12o3l@tiscali.nl] 
Sent: Wednesday, April 09, 2008 5:43 PM
To: sonic.zhang@analog.com
Cc: uclinux-dist-devel@blackfin.uclinux.org; 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@tiscali.nl>
---
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);
 }