[PATCH] input/misc: rotary-encoder: Set gpio direction

[PATCH] input/misc: rotary-encoder: Set gpio direction

[Andrew Clayton]

While trying to get a rotary encoder working under a beagle board using 
the drivers/input/misc/rotary-encoder.c driver, we found that even with 
the right pin mux settings configured through /sys/kernel/debug/omap_mux/*, 
i.e INPUT_PULLUP and MODE4, the gpio_get_value() functions only ever 
returned 1.

By explicitly calling gpio_direction_input() after each requested gpio, 
the driver started working and started returning correct input events.
 
The following is the patch that works for us. What do you think?

Cheers,
Andrew


Set the gpio direction to input for each requested gpio.

Even with the correct pin mux settings, you still need to explicitly 
set the gpio direction. Call gpio_direction_input() after each 
requested gpio.

Signed-off-by: Andrew Clayton <andrew@digital-domain.net>
---
diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
index 3b9f588..4ae0793 100644
--- a/drivers/input/misc/rotary_encoder.c
+++ b/drivers/input/misc/rotary_encoder.c
@@ -152,6 +152,13 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
 		goto exit_unregister_input;
 	}
 
+	err = gpio_direction_input(pdata->gpio_a);
+	if (err) {
+		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
+			pdata->gpio_a);
+		goto exit_unregister_input;
+	}
+
 	err = gpio_request(pdata->gpio_b, DRV_NAME);
 	if (err) {
 		dev_err(&pdev->dev, "unable to request GPIO %d\n",
@@ -159,6 +166,13 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
 		goto exit_free_gpio_a;
 	}
 
+	err = gpio_direction_input(pdata->gpio_b);
+	if (err) {
+		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
+			pdata->gpio_b);
+		goto exit_free_gpio_a;
+	}
+
 	/* request the IRQs */
 	err = request_irq(encoder->irq_a, &rotary_encoder_irq,
 			  IORESOURCE_IRQ_HIGHEDGE | IORESOURCE_IRQ_LOWEDGE,

RE: [PATCH] input/misc: rotary-encoder: Set gpio direction

[H Hartley Sweeten]

On Monday, February 08, 2010 2:04 PM, Andrew Clayton wrote:
> While trying to get a rotary encoder working under a beagle board using 
> the drivers/input/misc/rotary-encoder.c driver, we found that even with 
> the right pin mux settings configured through /sys/kernel/debug/omap_mux/*, 
> i.e INPUT_PULLUP and MODE4, the gpio_get_value() functions only ever 
> returned 1.
> 
> By explicitly calling gpio_direction_input() after each requested gpio, 
> the driver started working and started returning correct input events.
> 
> The following is the patch that works for us. What do you think?

On the ep93xx the gpio's default as inputs.  The gpio's must default as
outputs on the beagle board.  I never noticed the missing direction set
call.

Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com>

> Cheers,
> Andrew
> 
> 
> Set the gpio direction to input for each requested gpio.
> 
> Even with the correct pin mux settings, you still need to explicitly 
> set the gpio direction. Call gpio_direction_input() after each 
> requested gpio.
> 
> Signed-off-by: Andrew Clayton <andrew@digital-domain.net>
> ---
> diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
> index 3b9f588..4ae0793 100644
> --- a/drivers/input/misc/rotary_encoder.c
> +++ b/drivers/input/misc/rotary_encoder.c
> @@ -152,6 +152,13 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
>  		goto exit_unregister_input;
>  	}
>  
> +	err = gpio_direction_input(pdata->gpio_a);
> +	if (err) {
> +		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
> +			pdata->gpio_a);
> +		goto exit_unregister_input;
> +	}
> +
>  	err = gpio_request(pdata->gpio_b, DRV_NAME);
>  	if (err) {
>  		dev_err(&pdev->dev, "unable to request GPIO %d\n",
> @@ -159,6 +166,13 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
>  		goto exit_free_gpio_a;
>  	}
>  
> +	err = gpio_direction_input(pdata->gpio_b);
> +	if (err) {
> +		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
> +			pdata->gpio_b);
> +		goto exit_free_gpio_a;
> +	}
> +
>  	/* request the IRQs */
>  	err = request_irq(encoder->irq_a, &rotary_encoder_irq,
>  			  IORESOURCE_IRQ_HIGHEDGE | IORESOURCE_IRQ_LOWEDGE,

Re: [PATCH] input/misc: rotary-encoder: Set gpio direction

[Daniel Mack]

On Mon, Feb 08, 2010 at 09:03:50PM +0000, Andrew Clayton wrote:
> While trying to get a rotary encoder working under a beagle board using 
> the drivers/input/misc/rotary-encoder.c driver, we found that even with 
> the right pin mux settings configured through /sys/kernel/debug/omap_mux/*, 
> i.e INPUT_PULLUP and MODE4, the gpio_get_value() functions only ever 
> returned 1.
> 
> By explicitly calling gpio_direction_input() after each requested gpio, 
> the driver started working and started returning correct input events.
>  
> The following is the patch that works for us. What do you think?

Yep, that looks good to me, thanks!

Acked-by: Daniel Mack <daniel@caiaq.de>

> Set the gpio direction to input for each requested gpio.
> 
> Even with the correct pin mux settings, you still need to explicitly 
> set the gpio direction. Call gpio_direction_input() after each 
> requested gpio.
> 
> Signed-off-by: Andrew Clayton <andrew@digital-domain.net>
> ---
> diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
> index 3b9f588..4ae0793 100644
> --- a/drivers/input/misc/rotary_encoder.c
> +++ b/drivers/input/misc/rotary_encoder.c
> @@ -152,6 +152,13 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
>  		goto exit_unregister_input;
>  	}
>  
> +	err = gpio_direction_input(pdata->gpio_a);
> +	if (err) {
> +		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
> +			pdata->gpio_a);
> +		goto exit_unregister_input;
> +	}
> +
>  	err = gpio_request(pdata->gpio_b, DRV_NAME);
>  	if (err) {
>  		dev_err(&pdev->dev, "unable to request GPIO %d\n",
> @@ -159,6 +166,13 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
>  		goto exit_free_gpio_a;
>  	}
>  
> +	err = gpio_direction_input(pdata->gpio_b);
> +	if (err) {
> +		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
> +			pdata->gpio_b);
> +		goto exit_free_gpio_a;
> +	}
> +
>  	/* request the IRQs */
>  	err = request_irq(encoder->irq_a, &rotary_encoder_irq,
>  			  IORESOURCE_IRQ_HIGHEDGE | IORESOURCE_IRQ_LOWEDGE,

Re: [PATCH] input/misc: rotary-encoder: Set gpio direction

[Dmitry Torokhov]

On Monday 08 February 2010 02:12:06 pm Daniel Mack wrote:
> On Mon, Feb 08, 2010 at 09:03:50PM +0000, Andrew Clayton wrote:
> > While trying to get a rotary encoder working under a beagle board using
> > the drivers/input/misc/rotary-encoder.c driver, we found that even with
> > the right pin mux settings configured through
> > /sys/kernel/debug/omap_mux/*, i.e INPUT_PULLUP and MODE4, the
> > gpio_get_value() functions only ever returned 1.
> >
> > By explicitly calling gpio_direction_input() after each requested gpio,
> > the driver started working and started returning correct input events.
> >
> > The following is the patch that works for us. What do you think?
> 
> Yep, that looks good to me, thanks!
> 
> Acked-by: Daniel Mack <daniel@caiaq.de>

.33 material or hold off till .34?

-- 
Dmitry

Re: [PATCH] input/misc: rotary-encoder: Set gpio direction

[Mark Somerville]

[-- Attachment #1: Type: text/plain, Size: 2177 bytes --]

On Mon, Feb 08, 2010 at 09:03:50PM +0000, Andrew Clayton wrote:
> While trying to get a rotary encoder working under a beagle board using 
> the drivers/input/misc/rotary-encoder.c driver, we found that even with 
> the right pin mux settings configured through /sys/kernel/debug/omap_mux/*, 
> i.e INPUT_PULLUP and MODE4, the gpio_get_value() functions only ever 
> returned 1.
> 
> By explicitly calling gpio_direction_input() after each requested gpio, 
> the driver started working and started returning correct input events.
>
> The following is the patch that works for us. What do you think?

Adding my Signed-off-by tag:

Signed-off-by: Mark Somerville <mark@scottishclimbs.com>

> Cheers,
> Andrew
> 
> 
> Set the gpio direction to input for each requested gpio.
> 
> Even with the correct pin mux settings, you still need to explicitly 
> set the gpio direction. Call gpio_direction_input() after each 
> requested gpio.
> 
> Signed-off-by: Andrew Clayton <andrew@digital-domain.net>
> ---
> diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
> index 3b9f588..4ae0793 100644
> --- a/drivers/input/misc/rotary_encoder.c
> +++ b/drivers/input/misc/rotary_encoder.c
> @@ -152,6 +152,13 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
>  		goto exit_unregister_input;
>  	}
>  
> +	err = gpio_direction_input(pdata->gpio_a);
> +	if (err) {
> +		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
> +			pdata->gpio_a);
> +		goto exit_unregister_input;
> +	}
> +
>  	err = gpio_request(pdata->gpio_b, DRV_NAME);
>  	if (err) {
>  		dev_err(&pdev->dev, "unable to request GPIO %d\n",
> @@ -159,6 +166,13 @@ static int __devinit rotary_encoder_probe(struct platform_device *pdev)
>  		goto exit_free_gpio_a;
>  	}
>  
> +	err = gpio_direction_input(pdata->gpio_b);
> +	if (err) {
> +		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
> +			pdata->gpio_b);
> +		goto exit_free_gpio_a;
> +	}
> +
>  	/* request the IRQs */
>  	err = request_irq(encoder->irq_a, &rotary_encoder_irq,
>  			  IORESOURCE_IRQ_HIGHEDGE | IORESOURCE_IRQ_LOWEDGE,

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Re: [PATCH] input/misc: rotary-encoder: Set gpio direction

[Daniel Mack]

On Mon, Feb 08, 2010 at 04:18:23PM -0800, Dmitry Torokhov wrote:
> On Monday 08 February 2010 02:12:06 pm Daniel Mack wrote:
> > On Mon, Feb 08, 2010 at 09:03:50PM +0000, Andrew Clayton wrote:
> > > While trying to get a rotary encoder working under a beagle board using
> > > the drivers/input/misc/rotary-encoder.c driver, we found that even with
> > > the right pin mux settings configured through
> > > /sys/kernel/debug/omap_mux/*, i.e INPUT_PULLUP and MODE4, the
> > > gpio_get_value() functions only ever returned 1.
> > >
> > > By explicitly calling gpio_direction_input() after each requested gpio,
> > > the driver started working and started returning correct input events.
> > >
> > > The following is the patch that works for us. What do you think?
> > 
> > Yep, that looks good to me, thanks!
> > 
> > Acked-by: Daniel Mack <daniel@caiaq.de>
> 
> .33 material or hold off till .34?

Hmm, it doesn't fix any existing upstream platform, so I think it should
be fine for .34.

Thanks,
Daniel

Re: [PATCH] input/misc: rotary-encoder: Set gpio direction

[Dmitry Torokhov]

On Tue, Feb 09, 2010 at 02:30:29AM +0100, Daniel Mack wrote:
> On Mon, Feb 08, 2010 at 04:18:23PM -0800, Dmitry Torokhov wrote:
> > On Monday 08 February 2010 02:12:06 pm Daniel Mack wrote:
> > > On Mon, Feb 08, 2010 at 09:03:50PM +0000, Andrew Clayton wrote:
> > > > While trying to get a rotary encoder working under a beagle board using
> > > > the drivers/input/misc/rotary-encoder.c driver, we found that even with
> > > > the right pin mux settings configured through
> > > > /sys/kernel/debug/omap_mux/*, i.e INPUT_PULLUP and MODE4, the
> > > > gpio_get_value() functions only ever returned 1.
> > > >
> > > > By explicitly calling gpio_direction_input() after each requested gpio,
> > > > the driver started working and started returning correct input events.
> > > >
> > > > The following is the patch that works for us. What do you think?
> > > 
> > > Yep, that looks good to me, thanks!
> > > 
> > > Acked-by: Daniel Mack <daniel@caiaq.de>
> > 
> > .33 material or hold off till .34?
> 
> Hmm, it doesn't fix any existing upstream platform, so I think it should
> be fine for .34.
> 

Applied to 'next' then, thank you.

-- 
Dmitry