Commit af794928 authored May 17, 2018 by Benjamin Herrenschmidt Committed by Linus Walleij May 23, 2018

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>

parent d5dbf9c2

drivers/gpio/gpio-aspeed.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -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;