From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Thu, 17 May 2018 08:11:56 +0000 (+1000)
Subject: gpio: aspeed: Set output latch before changing direction
X-Git-Tag: v4.19~849^2~16
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=af7949284910a1f0b7814625051b8acf99af74d2;p=platform%2Fkernel%2Flinux-rpi.git

gpio: aspeed: Set output latch before changing direction

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>
Reviewed-by: Christopher Bostic <cbostic@linux.vnet.ibm.com>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---

diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
index 77e485557498..f210bed83dd6 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;