[PATCH] pch_gpio: set value before enabling output direction

[PATCH] pch_gpio: set value before enabling output direction

[Alexander Stein]

From: Daniel Krueger <daniel.krueger@systec-electronic.com>

This ensures that the output signal does not toggle if set to high.

Signed-off-by: Daniel Krueger <daniel.krueger@systec-electronic.com>
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
---
 drivers/gpio/gpio-pch.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpio/gpio-pch.c b/drivers/gpio/gpio-pch.c
index 9656c19..83a1563 100644
--- a/drivers/gpio/gpio-pch.c
+++ b/drivers/gpio/gpio-pch.c
@@ -138,9 +138,6 @@ static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
 	unsigned long flags;
 
 	spin_lock_irqsave(&chip->spinlock, flags);
-	pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
-	pm |= (1 << nr);
-	iowrite32(pm, &chip->reg->pm);
 
 	reg_val = ioread32(&chip->reg->po);
 	if (val)
@@ -148,6 +145,11 @@ static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
 	else
 		reg_val &= ~(1 << nr);
 	iowrite32(reg_val, &chip->reg->po);
+
+	pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
+	pm |= (1 << nr);
+	iowrite32(pm, &chip->reg->pm);
+
 	spin_unlock_irqrestore(&chip->spinlock, flags);
 
 	return 0;
-- 
1.8.3.2

Re: [PATCH] pch_gpio: set value before enabling output direction

[Linus Walleij]

On Tue, Mar 25, 2014 at 10:32 AM, Alexander Stein
<alexander.stein@systec-electronic.com> wrote:

> From: Daniel Krueger <daniel.krueger@systec-electronic.com>
>
> This ensures that the output signal does not toggle if set to high.
>
> Signed-off-by: Daniel Krueger <daniel.krueger@systec-electronic.com>
> Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>

Patch applied,

Alexander, would you consider doing a patch adding yourself
as maintainer of this driver in the MAINTAINERS file?

Yours,
Linus Walleij

Re: [PATCH] pch_gpio: set value before enabling output direction

[Alexander Stein]

Hello Linus,

On Thursday 27 March 2014 10:22:40, Linus Walleij wrote:
> On Tue, Mar 25, 2014 at 10:32 AM, Alexander Stein
> <alexander.stein@systec-electronic.com> wrote:
> 
> > From: Daniel Krueger <daniel.krueger@systec-electronic.com>
> >
> > This ensures that the output signal does not toggle if set to high.
> >
> > Signed-off-by: Daniel Krueger <daniel.krueger@systec-electronic.com>
> > Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
> 
> Patch applied,
> 
> Alexander, would you consider doing a patch adding yourself
> as maintainer of this driver in the MAINTAINERS file?

Thanks for offering this. I'm inclined to this, but the problem ist I won't have
good or even permanent access to this hardware :( So I have to decline.

Best regards,
Alexander
-- 
Dipl.-Inf. Alexander Stein

SYS TEC electronic GmbH
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Tel.: 03765 38600-1156
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Email: alexander.stein@systec-electronic.com
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