From: linux@arm•linux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH 11/13] FB: sa1100: make GPIO configuration setting safe
Date: Sat, 04 Feb 2012 09:41:48 +0000 [thread overview]
Message-ID: <E1Rtc7w-0000b2-Ur@rmk-PC.arm.linux.org.uk> (raw)
In-Reply-To: <20120204093744.GQ889@n2100.arm.linux.org.uk>
The sa1100fb driver needs to set the GPIO direction and alternate
function register according to the panel that we're driving. We've
done this in the driver by read-modify-writing the register, which
may cause problems with races. Fix this with a minimal change.
Signed-off-by: Russell King <rmk+kernel@arm•linux.org.uk>
---
drivers/video/sa1100fb.c | 11 +++++++++++
1 files changed, 11 insertions(+), 0 deletions(-)
diff --git a/drivers/video/sa1100fb.c b/drivers/video/sa1100fb.c
index d1d97ca..b644f0f 100644
--- a/drivers/video/sa1100fb.c
+++ b/drivers/video/sa1100fb.c
@@ -761,8 +761,19 @@ static void sa1100fb_setup_gpio(struct sa1100fb_info *fbi)
}
if (mask) {
+ unsigned long flags;
+
+ /*
+ * SA-1100 requires the GPIO direction register set
+ * appropriately for the alternate function. Hence
+ * we set it here via bitmask rather than excessive
+ * fiddling via the GPIO subsystem - and even then
+ * we'll still have to deal with GAFR.
+ */
+ local_irq_save(flags);
GPDR |= mask;
GAFR |= mask;
+ local_irq_restore(flags);
}
}
--
1.7.4.4
next prev parent reply other threads:[~2012-02-04 9:41 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-04 9:37 [PATCH 00/13] sa1100fb cleanups Russell King - ARM Linux
2012-02-04 9:38 ` [PATCH 01/13] FB: sa1100: avoid section mismatch warnings Russell King - ARM Linux
2012-02-04 9:38 ` [PATCH 02/13] FB: sa1100: add .owner initializer to driver structure Russell King - ARM Linux
2012-02-04 9:39 ` [PATCH 03/13] FB: sa1100: constify rgb structures Russell King - ARM Linux
2012-02-04 9:39 ` [PATCH 04/13] FB: sa1100: convert printks to dev_xxx() Russell King - ARM Linux
2012-02-04 9:39 ` [PATCH 05/13] FB: sa1100: combine RGB bitfield overrides into sa1100fb_mach_info Russell King - ARM Linux
2012-02-04 9:40 ` [PATCH 06/13] FB: sa1100: move machine inf structures to <video/sa1100fb.h> Russell King - ARM Linux
2012-02-04 9:40 ` [PATCH 07/13] FB: sa1100: move platform data to platform files Russell King - ARM Linux
2012-02-04 9:40 ` [PATCH 08/13] FB: sa1100: remove global sa1100fb_.*_power function pointers Russell King - ARM Linux
2012-02-04 9:41 ` [PATCH 09/13] FB: sa1100: remove assabet specific initialization Russell King - ARM Linux
2012-02-04 9:41 ` [PATCH 10/13] FB: sa1100: use inf members directly Russell King - ARM Linux
2012-02-04 9:41 ` Russell King - ARM Linux [this message]
2012-02-04 9:42 ` [PATCH 12/13] FB: sa11x0: fix shannon GPSR/GPCR accesses Russell King - ARM Linux
2012-02-04 9:42 ` [PATCH 13/13] FB: sa11x0: convert shannon display enable accesses to use GPIO subsystem Russell King - ARM Linux
2012-02-19 22:40 ` [PATCH 00/13] sa1100fb cleanups Florian Tobias Schandinat
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