[PATCH] drm/tegra: switch to using devm_gpiod_get_optional

[PATCH] drm/tegra: switch to using devm_gpiod_get_optional

[Dmitry Torokhov]

We do not really need to use API that fetches GPIO data from an
arbitrary device tree node, as we are dealing with device tree node
assigned to the device structure. We can easily switch to
devm_gpiod_get_optional() plus gpiod_set_consumer_name() and clean up
the code.

Note this is part of efforts to get rid of [devm_]gpiod_get_from_of_node
in drivers so that gpiolib can be cleaned up.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/gpu/drm/tegra/output.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c
index bdcaa4c7168c..b4248125b844 100644
--- a/drivers/gpu/drm/tegra/output.c
+++ b/drivers/gpu/drm/tegra/output.c
@@ -121,19 +121,15 @@ int tegra_output_probe(struct tegra_output *output)
 		of_node_put(ddc);
 	}
 
-	output->hpd_gpio = devm_gpiod_get_from_of_node(output->dev,
-						       output->of_node,
-						       "nvidia,hpd-gpio", 0,
-						       GPIOD_IN,
-						       "HDMI hotplug detect");
-	if (IS_ERR(output->hpd_gpio)) {
-		if (PTR_ERR(output->hpd_gpio) != -ENOENT)
-			return PTR_ERR(output->hpd_gpio);
-
-		output->hpd_gpio = NULL;
-	}
+	output->hpd_gpio = devm_gpiod_get_optional(output->dev,
+						   "nvidia,hpd", GPIOD_IN);
+	if (IS_ERR(output->hpd_gpio))
+		return PTR_ERR(output->hpd_gpio);
 
 	if (output->hpd_gpio) {
+		gpiod_set_consumer_name(output->hpd_gpio,
+					"HDMI hotplug detect");
+
 		err = gpiod_to_irq(output->hpd_gpio);
 		if (err < 0) {
 			dev_err(output->dev, "gpiod_to_irq(): %d\n", err);
-- 
2.23.0.237.gc6a4ce50a0-goog


-- 
Dmitry

Re: [PATCH] drm/tegra: switch to using devm_gpiod_get_optional

[Thierry Reding]

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On Sun, Sep 15, 2019 at 12:13:23AM -0700, Dmitry Torokhov wrote:
> We do not really need to use API that fetches GPIO data from an
> arbitrary device tree node, as we are dealing with device tree node
> assigned to the device structure. We can easily switch to
> devm_gpiod_get_optional() plus gpiod_set_consumer_name() and clean up
> the code.
> 
> Note this is part of efforts to get rid of [devm_]gpiod_get_from_of_node
> in drivers so that gpiolib can be cleaned up.
> 
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---
>  drivers/gpu/drm/tegra/output.c | 18 +++++++-----------
>  1 file changed, 7 insertions(+), 11 deletions(-)

We can't do that. There's a special case in rgb.c that sets
output->of_node to something different than output->dev, so we actually
need to pass the struct device_node * separately.

Thierry

> 
> diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c
> index bdcaa4c7168c..b4248125b844 100644
> --- a/drivers/gpu/drm/tegra/output.c
> +++ b/drivers/gpu/drm/tegra/output.c
> @@ -121,19 +121,15 @@ int tegra_output_probe(struct tegra_output *output)
>  		of_node_put(ddc);
>  	}
>  
> -	output->hpd_gpio = devm_gpiod_get_from_of_node(output->dev,
> -						       output->of_node,
> -						       "nvidia,hpd-gpio", 0,
> -						       GPIOD_IN,
> -						       "HDMI hotplug detect");
> -	if (IS_ERR(output->hpd_gpio)) {
> -		if (PTR_ERR(output->hpd_gpio) != -ENOENT)
> -			return PTR_ERR(output->hpd_gpio);
> -
> -		output->hpd_gpio = NULL;
> -	}
> +	output->hpd_gpio = devm_gpiod_get_optional(output->dev,
> +						   "nvidia,hpd", GPIOD_IN);
> +	if (IS_ERR(output->hpd_gpio))
> +		return PTR_ERR(output->hpd_gpio);
>  
>  	if (output->hpd_gpio) {
> +		gpiod_set_consumer_name(output->hpd_gpio,
> +					"HDMI hotplug detect");
> +
>  		err = gpiod_to_irq(output->hpd_gpio);
>  		if (err < 0) {
>  			dev_err(output->dev, "gpiod_to_irq(): %d\n", err);
> -- 
> 2.23.0.237.gc6a4ce50a0-goog
> 
> 
> -- 
> Dmitry

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Re: [PATCH] drm/tegra: switch to using devm_gpiod_get_optional

[Dmitry Torokhov]

On Mon, Sep 16, 2019 at 03:59:04PM +0200, Thierry Reding wrote:
> On Sun, Sep 15, 2019 at 12:13:23AM -0700, Dmitry Torokhov wrote:
> > We do not really need to use API that fetches GPIO data from an
> > arbitrary device tree node, as we are dealing with device tree node
> > assigned to the device structure. We can easily switch to
> > devm_gpiod_get_optional() plus gpiod_set_consumer_name() and clean up
> > the code.
> > 
> > Note this is part of efforts to get rid of [devm_]gpiod_get_from_of_node
> > in drivers so that gpiolib can be cleaned up.
> > 
> > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> > ---
> >  drivers/gpu/drm/tegra/output.c | 18 +++++++-----------
> >  1 file changed, 7 insertions(+), 11 deletions(-)
> 
> We can't do that. There's a special case in rgb.c that sets
> output->of_node to something different than output->dev, so we actually
> need to pass the struct device_node * separately.

Ugh, brainfart on my part. I totally read it is output->dev.of_node,
similar to another driver I was looking at...

Please discard, there will be another patch changing
devm_gpiod_get_from_of_node() to devm_fwnode_gpiod_get() once Linus
merges this new GPIO method.

Thanks.

-- 
Dmitry