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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: openbmc@lists.ozlabs.org
Cc: Christopher Bostic <cbostic@linux.vnet.ibm.com>,
 Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: [PATCH linux dev-4.13 1/6] gpio/aspeed: Set output latch before
 changing direction
Date: Tue,  8 May 2018 11:06:35 +1000
Message-Id: <20180508010640.14113-1-benh@kernel.crashing.org>
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In aspeed_gpio_dir_out(), we need to establish the new output
value in the output latch *before* we change the direction
to output in order to avoid a glitch on the output line if
the previous value of the latch was different.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
 drivers/gpio/gpio-aspeed.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
index 67f3eae3b550..ac54b9b25f74 100644
--- a/drivers/gpio/gpio-aspeed.c
+++ b/drivers/gpio/gpio-aspeed.c
@@ -287,11 +287,10 @@ static int aspeed_gpio_dir_out(struct gpio_chip *gc,
 
 	spin_lock_irqsave(&gpio->lock, flags);
 
+	__aspeed_gpio_set(gc, offset, val);
 	reg = ioread32(bank_val_reg(gpio, bank, GPIO_DIR));
 	iowrite32(reg | GPIO_BIT(offset), bank_val_reg(gpio, bank, GPIO_DIR));
 
-	__aspeed_gpio_set(gc, offset, val);
-
 	spin_unlock_irqrestore(&gpio->lock, flags);
 
 	return 0;
-- 
2.17.0