[PATCH v2 1/2] drm/omap/dss: Use of_property_present() to test existence of DT property

[PATCH v2 1/2] drm/omap/dss: Use of_property_present() to test existence of DT property

[Krzysztof Kozlowski]

of_property_read_bool() should be used only on boolean properties.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

---

Changes in v2:
1. New patch - split from the next one.
---
 drivers/gpu/drm/omapdrm/dss/dss.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/omapdrm/dss/dss.c b/drivers/gpu/drm/omapdrm/dss/dss.c
index 7b2df3185de4..319f0a1d23a7 100644
--- a/drivers/gpu/drm/omapdrm/dss/dss.c
+++ b/drivers/gpu/drm/omapdrm/dss/dss.c
@@ -1236,7 +1236,7 @@ static int dss_video_pll_probe(struct dss_device *dss)
 	if (!np)
 		return 0;
 
-	if (of_property_read_bool(np, "syscon-pll-ctrl")) {
+	if (of_property_present(np, "syscon-pll-ctrl")) {
 		dss->syscon_pll_ctrl = syscon_regmap_lookup_by_phandle(np,
 			"syscon-pll-ctrl");
 		if (IS_ERR(dss->syscon_pll_ctrl)) {
-- 
2.43.0

[PATCH v2 2/2] drm/omap/dss: Use syscon_regmap_lookup_by_phandle_args

[Krzysztof Kozlowski]

Use syscon_regmap_lookup_by_phandle_args() which is a wrapper over
syscon_regmap_lookup_by_phandle() combined with getting the syscon
argument.  Except simpler code this annotates within one line that given
phandle has arguments, so grepping for code would be easier.

There is also no real benefit in printing errors on missing syscon
argument, because this is done just too late: runtime check on
static/build-time data.  Dtschema and Devicetree bindings offer the
static/build-time check for this already.

Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

---

Changes in v2:
1. Split of_property_present into previous patch.
2. Add tag.
---
 drivers/gpu/drm/omapdrm/dss/dss.c | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/omapdrm/dss/dss.c b/drivers/gpu/drm/omapdrm/dss/dss.c
index 319f0a1d23a7..692df747e2ae 100644
--- a/drivers/gpu/drm/omapdrm/dss/dss.c
+++ b/drivers/gpu/drm/omapdrm/dss/dss.c
@@ -1237,20 +1237,14 @@ static int dss_video_pll_probe(struct dss_device *dss)
 		return 0;
 
 	if (of_property_present(np, "syscon-pll-ctrl")) {
-		dss->syscon_pll_ctrl = syscon_regmap_lookup_by_phandle(np,
-			"syscon-pll-ctrl");
+		dss->syscon_pll_ctrl =
+			syscon_regmap_lookup_by_phandle_args(np, "syscon-pll-ctrl",
+							     1, &dss->syscon_pll_ctrl_offset);
 		if (IS_ERR(dss->syscon_pll_ctrl)) {
 			dev_err(&pdev->dev,
 				"failed to get syscon-pll-ctrl regmap\n");
 			return PTR_ERR(dss->syscon_pll_ctrl);
 		}
-
-		if (of_property_read_u32_index(np, "syscon-pll-ctrl", 1,
-				&dss->syscon_pll_ctrl_offset)) {
-			dev_err(&pdev->dev,
-				"failed to get syscon-pll-ctrl offset\n");
-			return -EINVAL;
-		}
 	}
 
 	pll_regulator = devm_regulator_get(&pdev->dev, "vdda_video");
-- 
2.43.0

Re: [PATCH v2 1/2] drm/omap/dss: Use of_property_present() to test existence of DT property

[Tomi Valkeinen]

Hi,

On 14/01/2025 16:58, Krzysztof Kozlowski wrote:
> of_property_read_bool() should be used only on boolean properties.
> 
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> 
> ---
> 
> Changes in v2:
> 1. New patch - split from the next one.
> ---
>   drivers/gpu/drm/omapdrm/dss/dss.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/dss/dss.c b/drivers/gpu/drm/omapdrm/dss/dss.c
> index 7b2df3185de4..319f0a1d23a7 100644
> --- a/drivers/gpu/drm/omapdrm/dss/dss.c
> +++ b/drivers/gpu/drm/omapdrm/dss/dss.c
> @@ -1236,7 +1236,7 @@ static int dss_video_pll_probe(struct dss_device *dss)
>   	if (!np)
>   		return 0;
>   
> -	if (of_property_read_bool(np, "syscon-pll-ctrl")) {
> +	if (of_property_present(np, "syscon-pll-ctrl")) {
>   		dss->syscon_pll_ctrl = syscon_regmap_lookup_by_phandle(np,
>   			"syscon-pll-ctrl");
>   		if (IS_ERR(dss->syscon_pll_ctrl)) {

Thanks, applying these to drm-misc-next.

  Tomi