[PATCH v4 0/3] drm/tinydrm: drm_of_find_backlight helper

[PATCH v4 0/3] drm/tinydrm: drm_of_find_backlight helper

[Meghana Madhyastha]

This patchset introduces some changes such as move
tinydrm_of_find_backlight to drm_of.c and rename it to
drm_of_find_backlight for better organizational structure.

Changes in v4:
- Remove "devices like tinydrm" from the function comments.
- Made devm_drm_of_find_backlight_release an internal function.
- Add dummy versions of drm_of_backlight functions.

Meghana Madhyastha (3):
  drm/tinydrm: Move tinydrm_of_find_backlight into drm_of.c
  drm/tinydrm: Add devres versions of drm_of_find_backlight
  drm/tinydrm: Add the dummy versions of drm_of_find_backlight functions

 drivers/gpu/drm/drm_of.c                       | 91 ++++++++++++++++++++++++++
 drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c | 40 -----------
 drivers/gpu/drm/tinydrm/mi0283qt.c             |  3 +-
 include/drm/drm_of.h                           | 15 +++++
 include/drm/tinydrm/tinydrm-helpers.h          |  1 -
 5 files changed, 108 insertions(+), 42 deletions(-)

-- 
2.7.4

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[PATCH v4 0/3] drm/tinydrm: drm_of_find_backlight helper

[Meghana Madhyastha]

This patchset introduces some changes such as move
tinydrm_of_find_backlight to drm_of.c and rename it to
drm_of_find_backlight for better organizational structure.

Changes in v4:
- Remove "devices like tinydrm" from the function comments.
- Made devm_drm_of_find_backlight_release an internal function.
- Add dummy versions of drm_of_backlight functions.

Meghana Madhyastha (3):
  drm/tinydrm: Move tinydrm_of_find_backlight into drm_of.c
  drm/tinydrm: Add devres versions of drm_of_find_backlight
  drm/tinydrm: Add the dummy versions of drm_of_find_backlight functions

 drivers/gpu/drm/drm_of.c                       | 91 ++++++++++++++++++++++++++
 drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c | 40 -----------
 drivers/gpu/drm/tinydrm/mi0283qt.c             |  3 +-
 include/drm/drm_of.h                           | 15 +++++
 include/drm/tinydrm/tinydrm-helpers.h          |  1 -
 5 files changed, 108 insertions(+), 42 deletions(-)

-- 
2.7.4

[PATCH v4 1/3] drm/tinydrm: Move tinydrm_of_find_backlight into drm_of.c

[Meghana Madhyastha]

Rename tinydrm_of_find_backlight to drm_of_find_backlight
and move it into drm_of.c from tinydrm-helpers.c. This is
because other drivers in the drm subsystem might need to call
this function. In that case and otherwise, it is better from
an organizational point of view to move it into drm_of.c along
with the other _of.c functions.

Signed-off-by: Meghana Madhyastha <meghana.madhyastha@gmail.com>
---
Changes in v4:
-None

 drivers/gpu/drm/drm_of.c                       | 44 ++++++++++++++++++++++++++
 drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c | 40 -----------------------
 drivers/gpu/drm/tinydrm/mi0283qt.c             |  3 +-
 include/drm/drm_of.h                           |  1 +
 include/drm/tinydrm/tinydrm-helpers.h          |  1 -
 5 files changed, 47 insertions(+), 42 deletions(-)

diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index 8dafbdf..d878d3a 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c
@@ -1,6 +1,7 @@
 #include <linux/component.h>
 #include <linux/export.h>
 #include <linux/list.h>
+#include <linux/backlight.h>
 #include <linux/of_graph.h>
 #include <drm/drmP.h>
 #include <drm/drm_bridge.h>
@@ -260,3 +261,46 @@ int drm_of_find_panel_or_bridge(const struct device_node *np,
 	return ret;
 }
 EXPORT_SYMBOL_GPL(drm_of_find_panel_or_bridge);
+
+/**
+ * drm_of_find_backlight - Find backlight device in device-tree
+ * @dev: Device
+ *
+ * This function looks for a DT node pointed to by a property named 'backlight'
+ * and uses of_find_backlight_by_node() to get the backlight device.
+ * Additionally if the brightness property is zero, it is set to
+ * max_brightness.
+ *
+ * Note: It is the responsibility of the caller to call put_device() when
+ * releasing the resource.
+ *
+ * Returns:
+ * NULL if there's no backlight property.
+ * Error pointer -EPROBE_DEFER if the DT node is found, but no backlight device
+ * is found.
+ * If the backlight device is found, a pointer to the structure is returned.
+ */
+struct backlight_device *drm_of_find_backlight(struct device *dev)
+{
+	struct backlight_device *backlight;
+	struct device_node *np;
+
+	np = of_parse_phandle(dev->of_node, "backlight", 0);
+	if (!np)
+		return NULL;
+
+	backlight = of_find_backlight_by_node(np);
+	of_node_put(np);
+
+	if (!backlight)
+		return ERR_PTR(-EPROBE_DEFER);
+
+	if (!backlight->props.brightness) {
+		backlight->props.brightness = backlight->props.max_brightness;
+		DRM_DEBUG_KMS("Backlight brightness set to %d\n",
+			      backlight->props.brightness);
+	}
+
+	return backlight;
+}
+EXPORT_SYMBOL(drm_of_find_backlight);
diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
index bd6cce0..cd4c6a5 100644
--- a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
+++ b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
@@ -237,46 +237,6 @@ void tinydrm_xrgb8888_to_gray8(u8 *dst, void *vaddr, struct drm_framebuffer *fb,
 EXPORT_SYMBOL(tinydrm_xrgb8888_to_gray8);
 
 /**
- * tinydrm_of_find_backlight - Find backlight device in device-tree
- * @dev: Device
- *
- * This function looks for a DT node pointed to by a property named 'backlight'
- * and uses of_find_backlight_by_node() to get the backlight device.
- * Additionally if the brightness property is zero, it is set to
- * max_brightness.
- *
- * Returns:
- * NULL if there's no backlight property.
- * Error pointer -EPROBE_DEFER if the DT node is found, but no backlight device
- * is found.
- * If the backlight device is found, a pointer to the structure is returned.
- */
-struct backlight_device *tinydrm_of_find_backlight(struct device *dev)
-{
-	struct backlight_device *backlight;
-	struct device_node *np;
-
-	np = of_parse_phandle(dev->of_node, "backlight", 0);
-	if (!np)
-		return NULL;
-
-	backlight = of_find_backlight_by_node(np);
-	of_node_put(np);
-
-	if (!backlight)
-		return ERR_PTR(-EPROBE_DEFER);
-
-	if (!backlight->props.brightness) {
-		backlight->props.brightness = backlight->props.max_brightness;
-		DRM_DEBUG_KMS("Backlight brightness set to %d\n",
-			      backlight->props.brightness);
-	}
-
-	return backlight;
-}
-EXPORT_SYMBOL(tinydrm_of_find_backlight);
-
-/**
  * tinydrm_enable_backlight - Enable backlight helper
  * @backlight: Backlight device
  *
diff --git a/drivers/gpu/drm/tinydrm/mi0283qt.c b/drivers/gpu/drm/tinydrm/mi0283qt.c
index 7e5bb7d..5e3d635 100644
--- a/drivers/gpu/drm/tinydrm/mi0283qt.c
+++ b/drivers/gpu/drm/tinydrm/mi0283qt.c
@@ -12,6 +12,7 @@
 #include <drm/tinydrm/ili9341.h>
 #include <drm/tinydrm/mipi-dbi.h>
 #include <drm/tinydrm/tinydrm-helpers.h>
+#include <drm/drm_of.h>
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/module.h>
@@ -189,7 +190,7 @@ static int mi0283qt_probe(struct spi_device *spi)
 	if (IS_ERR(mipi->regulator))
 		return PTR_ERR(mipi->regulator);
 
-	mipi->backlight = tinydrm_of_find_backlight(dev);
+	mipi->backlight = drm_of_find_backlight(dev);
 	if (IS_ERR(mipi->backlight))
 		return PTR_ERR(mipi->backlight);
 
diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index 104dd51..e8fba5b 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -29,6 +29,7 @@ int drm_of_find_panel_or_bridge(const struct device_node *np,
 				int port, int endpoint,
 				struct drm_panel **panel,
 				struct drm_bridge **bridge);
+struct backlight_device *drm_of_find_backlight(struct device *dev);
 #else
 static inline uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
 						  struct device_node *port)
diff --git a/include/drm/tinydrm/tinydrm-helpers.h b/include/drm/tinydrm/tinydrm-helpers.h
index d554ded..e40ef2d 100644
--- a/include/drm/tinydrm/tinydrm-helpers.h
+++ b/include/drm/tinydrm/tinydrm-helpers.h
@@ -46,7 +46,6 @@ void tinydrm_xrgb8888_to_rgb565(u16 *dst, void *vaddr,
 void tinydrm_xrgb8888_to_gray8(u8 *dst, void *vaddr, struct drm_framebuffer *fb,
 			       struct drm_clip_rect *clip);
 
-struct backlight_device *tinydrm_of_find_backlight(struct device *dev);
 int tinydrm_enable_backlight(struct backlight_device *backlight);
 int tinydrm_disable_backlight(struct backlight_device *backlight);
 
-- 
2.7.4

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH v4 1/3] drm/tinydrm: Move tinydrm_of_find_backlight into drm_of.c

[Meghana Madhyastha]

Rename tinydrm_of_find_backlight to drm_of_find_backlight
and move it into drm_of.c from tinydrm-helpers.c. This is
because other drivers in the drm subsystem might need to call
this function. In that case and otherwise, it is better from
an organizational point of view to move it into drm_of.c along
with the other _of.c functions.

Signed-off-by: Meghana Madhyastha <meghana.madhyastha@gmail.com>
---
Changes in v4:
-None

 drivers/gpu/drm/drm_of.c                       | 44 ++++++++++++++++++++++++++
 drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c | 40 -----------------------
 drivers/gpu/drm/tinydrm/mi0283qt.c             |  3 +-
 include/drm/drm_of.h                           |  1 +
 include/drm/tinydrm/tinydrm-helpers.h          |  1 -
 5 files changed, 47 insertions(+), 42 deletions(-)

diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index 8dafbdf..d878d3a 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c
@@ -1,6 +1,7 @@
 #include <linux/component.h>
 #include <linux/export.h>
 #include <linux/list.h>
+#include <linux/backlight.h>
 #include <linux/of_graph.h>
 #include <drm/drmP.h>
 #include <drm/drm_bridge.h>
@@ -260,3 +261,46 @@ int drm_of_find_panel_or_bridge(const struct device_node *np,
 	return ret;
 }
 EXPORT_SYMBOL_GPL(drm_of_find_panel_or_bridge);
+
+/**
+ * drm_of_find_backlight - Find backlight device in device-tree
+ * @dev: Device
+ *
+ * This function looks for a DT node pointed to by a property named 'backlight'
+ * and uses of_find_backlight_by_node() to get the backlight device.
+ * Additionally if the brightness property is zero, it is set to
+ * max_brightness.
+ *
+ * Note: It is the responsibility of the caller to call put_device() when
+ * releasing the resource.
+ *
+ * Returns:
+ * NULL if there's no backlight property.
+ * Error pointer -EPROBE_DEFER if the DT node is found, but no backlight device
+ * is found.
+ * If the backlight device is found, a pointer to the structure is returned.
+ */
+struct backlight_device *drm_of_find_backlight(struct device *dev)
+{
+	struct backlight_device *backlight;
+	struct device_node *np;
+
+	np = of_parse_phandle(dev->of_node, "backlight", 0);
+	if (!np)
+		return NULL;
+
+	backlight = of_find_backlight_by_node(np);
+	of_node_put(np);
+
+	if (!backlight)
+		return ERR_PTR(-EPROBE_DEFER);
+
+	if (!backlight->props.brightness) {
+		backlight->props.brightness = backlight->props.max_brightness;
+		DRM_DEBUG_KMS("Backlight brightness set to %d\n",
+			      backlight->props.brightness);
+	}
+
+	return backlight;
+}
+EXPORT_SYMBOL(drm_of_find_backlight);
diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
index bd6cce0..cd4c6a5 100644
--- a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
+++ b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
@@ -237,46 +237,6 @@ void tinydrm_xrgb8888_to_gray8(u8 *dst, void *vaddr, struct drm_framebuffer *fb,
 EXPORT_SYMBOL(tinydrm_xrgb8888_to_gray8);
 
 /**
- * tinydrm_of_find_backlight - Find backlight device in device-tree
- * @dev: Device
- *
- * This function looks for a DT node pointed to by a property named 'backlight'
- * and uses of_find_backlight_by_node() to get the backlight device.
- * Additionally if the brightness property is zero, it is set to
- * max_brightness.
- *
- * Returns:
- * NULL if there's no backlight property.
- * Error pointer -EPROBE_DEFER if the DT node is found, but no backlight device
- * is found.
- * If the backlight device is found, a pointer to the structure is returned.
- */
-struct backlight_device *tinydrm_of_find_backlight(struct device *dev)
-{
-	struct backlight_device *backlight;
-	struct device_node *np;
-
-	np = of_parse_phandle(dev->of_node, "backlight", 0);
-	if (!np)
-		return NULL;
-
-	backlight = of_find_backlight_by_node(np);
-	of_node_put(np);
-
-	if (!backlight)
-		return ERR_PTR(-EPROBE_DEFER);
-
-	if (!backlight->props.brightness) {
-		backlight->props.brightness = backlight->props.max_brightness;
-		DRM_DEBUG_KMS("Backlight brightness set to %d\n",
-			      backlight->props.brightness);
-	}
-
-	return backlight;
-}
-EXPORT_SYMBOL(tinydrm_of_find_backlight);
-
-/**
  * tinydrm_enable_backlight - Enable backlight helper
  * @backlight: Backlight device
  *
diff --git a/drivers/gpu/drm/tinydrm/mi0283qt.c b/drivers/gpu/drm/tinydrm/mi0283qt.c
index 7e5bb7d..5e3d635 100644
--- a/drivers/gpu/drm/tinydrm/mi0283qt.c
+++ b/drivers/gpu/drm/tinydrm/mi0283qt.c
@@ -12,6 +12,7 @@
 #include <drm/tinydrm/ili9341.h>
 #include <drm/tinydrm/mipi-dbi.h>
 #include <drm/tinydrm/tinydrm-helpers.h>
+#include <drm/drm_of.h>
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/module.h>
@@ -189,7 +190,7 @@ static int mi0283qt_probe(struct spi_device *spi)
 	if (IS_ERR(mipi->regulator))
 		return PTR_ERR(mipi->regulator);
 
-	mipi->backlight = tinydrm_of_find_backlight(dev);
+	mipi->backlight = drm_of_find_backlight(dev);
 	if (IS_ERR(mipi->backlight))
 		return PTR_ERR(mipi->backlight);
 
diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index 104dd51..e8fba5b 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -29,6 +29,7 @@ int drm_of_find_panel_or_bridge(const struct device_node *np,
 				int port, int endpoint,
 				struct drm_panel **panel,
 				struct drm_bridge **bridge);
+struct backlight_device *drm_of_find_backlight(struct device *dev);
 #else
 static inline uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
 						  struct device_node *port)
diff --git a/include/drm/tinydrm/tinydrm-helpers.h b/include/drm/tinydrm/tinydrm-helpers.h
index d554ded..e40ef2d 100644
--- a/include/drm/tinydrm/tinydrm-helpers.h
+++ b/include/drm/tinydrm/tinydrm-helpers.h
@@ -46,7 +46,6 @@ void tinydrm_xrgb8888_to_rgb565(u16 *dst, void *vaddr,
 void tinydrm_xrgb8888_to_gray8(u8 *dst, void *vaddr, struct drm_framebuffer *fb,
 			       struct drm_clip_rect *clip);
 
-struct backlight_device *tinydrm_of_find_backlight(struct device *dev);
 int tinydrm_enable_backlight(struct backlight_device *backlight);
 int tinydrm_disable_backlight(struct backlight_device *backlight);
 
-- 
2.7.4

[PATCH v4 2/3] drm/tinydrm: Add devres versions of drm_of_find_backlight

[Meghana Madhyastha]

Add devm_drm_of_find_backlight and the corresponding release
function because some drivers such as tinydrm use devres versions
of functions for requiring device resources.

Signed-off-by: Meghana Madhyastha <meghana.madhyastha@gmail.com>
---
Changes in v4:
-Made the release function an internal static function.
-Removed specific reference to tinydrm in the function comments.

 drivers/gpu/drm/drm_of.c           | 47 ++++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/tinydrm/mi0283qt.c |  2 +-
 include/drm/drm_of.h               |  1 +
 3 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index d878d3a..cd80dfc 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c
@@ -304,3 +304,50 @@ struct backlight_device *drm_of_find_backlight(struct device *dev)
 	return backlight;
 }
 EXPORT_SYMBOL(drm_of_find_backlight);
+
+/**
+ * devm_drm_of_find_backlight_release - Release backlight device
+ * @dev: Device
+ *
+ * This is the release function corresponding to the devm_drm_of_find_backlight.
+ * Each devres entry is associated with a release function.
+ */
+static void devm_drm_of_find_backlight_release(void *data)
+{
+	put_device(data);
+}
+
+/**
+ * devm_drm_of_find_backlight - Find backlight device in device-tree
+ * devres version of the function
+ * @dev: Device
+ *
+ * This is the devres version of the function drm_of_find_backlight.
+ * Some drivers use devres versions of functions for
+ * requiring device resources.
+ *
+ * Returns:
+ * NULL if there's no backlight property.
+ * Error pointer -EPROBE_DEFER if the DT node is found, but no backlight device
+ * is found.
+ * If the backlight device is found, a pointer to the structure is returned.
+ */
+struct backlight_device *devm_drm_of_find_backlight(struct device *dev)
+{
+	struct backlight_device *backlight;
+	int ret;
+
+	backlight = drm_of_find_backlight(dev);
+	if (IS_ERR_OR_NULL(backlight))
+		return backlight;
+
+	ret = devm_add_action(dev, devm_drm_of_find_backlight_release,
+			      &backlight->dev);
+	if (ret) {
+		put_device(&backlight->dev);
+		return ERR_PTR(ret);
+	}
+
+	return backlight;
+}
+EXPORT_SYMBOL(devm_drm_of_find_backlight);
diff --git a/drivers/gpu/drm/tinydrm/mi0283qt.c b/drivers/gpu/drm/tinydrm/mi0283qt.c
index 5e3d635..d37f658 100644
--- a/drivers/gpu/drm/tinydrm/mi0283qt.c
+++ b/drivers/gpu/drm/tinydrm/mi0283qt.c
@@ -190,7 +190,7 @@ static int mi0283qt_probe(struct spi_device *spi)
 	if (IS_ERR(mipi->regulator))
 		return PTR_ERR(mipi->regulator);
 
-	mipi->backlight = drm_of_find_backlight(dev);
+	mipi->backlight = devm_drm_of_find_backlight(dev);
 	if (IS_ERR(mipi->backlight))
 		return PTR_ERR(mipi->backlight);
 
diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index e8fba5b..b2d6e0c 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -30,6 +30,7 @@ int drm_of_find_panel_or_bridge(const struct device_node *np,
 				struct drm_panel **panel,
 				struct drm_bridge **bridge);
 struct backlight_device *drm_of_find_backlight(struct device *dev);
+struct backlight_device *devm_drm_of_find_backlight(struct device *dev);
 #else
 static inline uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
 						  struct device_node *port)
-- 
2.7.4

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH v4 2/3] drm/tinydrm: Add devres versions of drm_of_find_backlight

[Meghana Madhyastha]

Add devm_drm_of_find_backlight and the corresponding release
function because some drivers such as tinydrm use devres versions
of functions for requiring device resources.

Signed-off-by: Meghana Madhyastha <meghana.madhyastha@gmail.com>
---
Changes in v4:
-Made the release function an internal static function.
-Removed specific reference to tinydrm in the function comments.

 drivers/gpu/drm/drm_of.c           | 47 ++++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/tinydrm/mi0283qt.c |  2 +-
 include/drm/drm_of.h               |  1 +
 3 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index d878d3a..cd80dfc 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c
@@ -304,3 +304,50 @@ struct backlight_device *drm_of_find_backlight(struct device *dev)
 	return backlight;
 }
 EXPORT_SYMBOL(drm_of_find_backlight);
+
+/**
+ * devm_drm_of_find_backlight_release - Release backlight device
+ * @dev: Device
+ *
+ * This is the release function corresponding to the devm_drm_of_find_backlight.
+ * Each devres entry is associated with a release function.
+ */
+static void devm_drm_of_find_backlight_release(void *data)
+{
+	put_device(data);
+}
+
+/**
+ * devm_drm_of_find_backlight - Find backlight device in device-tree
+ * devres version of the function
+ * @dev: Device
+ *
+ * This is the devres version of the function drm_of_find_backlight.
+ * Some drivers use devres versions of functions for
+ * requiring device resources.
+ *
+ * Returns:
+ * NULL if there's no backlight property.
+ * Error pointer -EPROBE_DEFER if the DT node is found, but no backlight device
+ * is found.
+ * If the backlight device is found, a pointer to the structure is returned.
+ */
+struct backlight_device *devm_drm_of_find_backlight(struct device *dev)
+{
+	struct backlight_device *backlight;
+	int ret;
+
+	backlight = drm_of_find_backlight(dev);
+	if (IS_ERR_OR_NULL(backlight))
+		return backlight;
+
+	ret = devm_add_action(dev, devm_drm_of_find_backlight_release,
+			      &backlight->dev);
+	if (ret) {
+		put_device(&backlight->dev);
+		return ERR_PTR(ret);
+	}
+
+	return backlight;
+}
+EXPORT_SYMBOL(devm_drm_of_find_backlight);
diff --git a/drivers/gpu/drm/tinydrm/mi0283qt.c b/drivers/gpu/drm/tinydrm/mi0283qt.c
index 5e3d635..d37f658 100644
--- a/drivers/gpu/drm/tinydrm/mi0283qt.c
+++ b/drivers/gpu/drm/tinydrm/mi0283qt.c
@@ -190,7 +190,7 @@ static int mi0283qt_probe(struct spi_device *spi)
 	if (IS_ERR(mipi->regulator))
 		return PTR_ERR(mipi->regulator);
 
-	mipi->backlight = drm_of_find_backlight(dev);
+	mipi->backlight = devm_drm_of_find_backlight(dev);
 	if (IS_ERR(mipi->backlight))
 		return PTR_ERR(mipi->backlight);
 
diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index e8fba5b..b2d6e0c 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -30,6 +30,7 @@ int drm_of_find_panel_or_bridge(const struct device_node *np,
 				struct drm_panel **panel,
 				struct drm_bridge **bridge);
 struct backlight_device *drm_of_find_backlight(struct device *dev);
+struct backlight_device *devm_drm_of_find_backlight(struct device *dev);
 #else
 static inline uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
 						  struct device_node *port)
-- 
2.7.4

[PATCH v4 3/3] drm/tinydrm: Add the dummy versions of drm_of_find_backlight functions

[Meghana Madhyastha]

Add the dummy versions (function definition returning -EINVAL) of
drm_of_find_backlight and devm_drm_of_find_backlight in the #else
part of the conditional directive in drm_of.h. This is needed
for drivers where CONFIG_OF is optional.

Signed-off-by: Meghana Madhyastha <meghana.madhyastha@gmail.com>
---
Changes in v4:
-This commit was not present in the previous versions.

 include/drm/drm_of.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index b2d6e0c..b11d55b 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -60,6 +60,7 @@ static inline int drm_of_encoder_active_endpoint(struct device_node *node,
 {
 	return -EINVAL;
 }
+
 static inline int drm_of_find_panel_or_bridge(const struct device_node *np,
 					      int port, int endpoint,
 					      struct drm_panel **panel,
@@ -67,6 +68,18 @@ static inline int drm_of_find_panel_or_bridge(const struct device_node *np,
 {
 	return -EINVAL;
 }
+
+static inline struct backlight_device *drm_of_find_backlight(
+					struct device *dev);
+{
+	return -EINVAL;
+}
+
+static inline struct backlight_device *devm_drm_of_find_backlight(
+						struct device *dev);
+{
+	return -EINVAL;
+}
 #endif
 
 static inline int drm_of_encoder_active_endpoint_id(struct device_node *node,
-- 
2.7.4

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH v4 3/3] drm/tinydrm: Add the dummy versions of drm_of_find_backlight functions

[Meghana Madhyastha]

Add the dummy versions (function definition returning -EINVAL) of
drm_of_find_backlight and devm_drm_of_find_backlight in the #else
part of the conditional directive in drm_of.h. This is needed
for drivers where CONFIG_OF is optional.

Signed-off-by: Meghana Madhyastha <meghana.madhyastha@gmail.com>
---
Changes in v4:
-This commit was not present in the previous versions.

 include/drm/drm_of.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index b2d6e0c..b11d55b 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -60,6 +60,7 @@ static inline int drm_of_encoder_active_endpoint(struct device_node *node,
 {
 	return -EINVAL;
 }
+
 static inline int drm_of_find_panel_or_bridge(const struct device_node *np,
 					      int port, int endpoint,
 					      struct drm_panel **panel,
@@ -67,6 +68,18 @@ static inline int drm_of_find_panel_or_bridge(const struct device_node *np,
 {
 	return -EINVAL;
 }
+
+static inline struct backlight_device *drm_of_find_backlight(
+					struct device *dev);
+{
+	return -EINVAL;
+}
+
+static inline struct backlight_device *devm_drm_of_find_backlight(
+						struct device *dev);
+{
+	return -EINVAL;
+}
 #endif
 
 static inline int drm_of_encoder_active_endpoint_id(struct device_node *node,
-- 
2.7.4

Re: [PATCH v4 2/3] drm/tinydrm: Add devres versions of drm_of_find_backlight

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 3446 bytes --]

Hi Meghana,

[auto build test ERROR on drm/drm-next]
[also build test ERROR on v4.14-rc2 next-20170929]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Meghana-Madhyastha/drm-tinydrm-drm_of_find_backlight-helper/20170930-122931
base:   git://people.freedesktop.org/~airlied/linux.git drm-next
config: x86_64-randconfig-x017-201739 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

Note: the linux-review/Meghana-Madhyastha/drm-tinydrm-drm_of_find_backlight-helper/20170930-122931 HEAD 4dc8fd20ad41e923832dc78cf4d8e7f98c0fedb9 builds fine.
      It only hurts bisectibility.

All errors (new ones prefixed by >>):

   drivers/gpu/drm/tinydrm/mi0283qt.c: In function 'mi0283qt_probe':
>> drivers/gpu/drm/tinydrm/mi0283qt.c:192:20: error: implicit declaration of function 'devm_drm_of_find_backlight' [-Werror=implicit-function-declaration]
     mipi->backlight = devm_drm_of_find_backlight(dev);
                       ^~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/tinydrm/mi0283qt.c:192:18: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
     mipi->backlight = devm_drm_of_find_backlight(dev);
                     ^
   cc1: some warnings being treated as errors

vim +/devm_drm_of_find_backlight +192 drivers/gpu/drm/tinydrm/mi0283qt.c

   163	
   164	static int mi0283qt_probe(struct spi_device *spi)
   165	{
   166		struct device *dev = &spi->dev;
   167		struct mipi_dbi *mipi;
   168		struct gpio_desc *dc;
   169		u32 rotation = 0;
   170		int ret;
   171	
   172		mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL);
   173		if (!mipi)
   174			return -ENOMEM;
   175	
   176		mipi->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
   177		if (IS_ERR(mipi->reset)) {
   178			dev_err(dev, "Failed to get gpio 'reset'\n");
   179			return PTR_ERR(mipi->reset);
   180		}
   181	
   182		dc = devm_gpiod_get_optional(dev, "dc", GPIOD_OUT_LOW);
   183		if (IS_ERR(dc)) {
   184			dev_err(dev, "Failed to get gpio 'dc'\n");
   185			return PTR_ERR(dc);
   186		}
   187	
   188		mipi->regulator = devm_regulator_get(dev, "power");
   189		if (IS_ERR(mipi->regulator))
   190			return PTR_ERR(mipi->regulator);
   191	
 > 192		mipi->backlight = devm_drm_of_find_backlight(dev);
   193		if (IS_ERR(mipi->backlight))
   194			return PTR_ERR(mipi->backlight);
   195	
   196		device_property_read_u32(dev, "rotation", &rotation);
   197	
   198		ret = mipi_dbi_spi_init(spi, mipi, dc);
   199		if (ret)
   200			return ret;
   201	
   202		ret = mipi_dbi_init(&spi->dev, mipi, &mi0283qt_pipe_funcs,
   203				    &mi0283qt_driver, &mi0283qt_mode, rotation);
   204		if (ret)
   205			return ret;
   206	
   207		ret = mi0283qt_init(mipi);
   208		if (ret)
   209			return ret;
   210	
   211		/* use devres to fini after drm unregister (drv->remove is before) */
   212		ret = devm_add_action(dev, mi0283qt_fini, mipi);
   213		if (ret) {
   214			mi0283qt_fini(mipi);
   215			return ret;
   216		}
   217	
   218		spi_set_drvdata(spi, mipi);
   219	
   220		return devm_tinydrm_register(&mipi->tinydrm);
   221	}
   222	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
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[-- Attachment #3: Type: text/plain, Size: 160 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH v4 2/3] drm/tinydrm: Add devres versions of drm_of_find_backlight

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 3446 bytes --]

Hi Meghana,

[auto build test ERROR on drm/drm-next]
[also build test ERROR on v4.14-rc2 next-20170929]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Meghana-Madhyastha/drm-tinydrm-drm_of_find_backlight-helper/20170930-122931
base:   git://people.freedesktop.org/~airlied/linux.git drm-next
config: x86_64-randconfig-x017-201739 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

Note: the linux-review/Meghana-Madhyastha/drm-tinydrm-drm_of_find_backlight-helper/20170930-122931 HEAD 4dc8fd20ad41e923832dc78cf4d8e7f98c0fedb9 builds fine.
      It only hurts bisectibility.

All errors (new ones prefixed by >>):

   drivers/gpu/drm/tinydrm/mi0283qt.c: In function 'mi0283qt_probe':
>> drivers/gpu/drm/tinydrm/mi0283qt.c:192:20: error: implicit declaration of function 'devm_drm_of_find_backlight' [-Werror=implicit-function-declaration]
     mipi->backlight = devm_drm_of_find_backlight(dev);
                       ^~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/tinydrm/mi0283qt.c:192:18: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
     mipi->backlight = devm_drm_of_find_backlight(dev);
                     ^
   cc1: some warnings being treated as errors

vim +/devm_drm_of_find_backlight +192 drivers/gpu/drm/tinydrm/mi0283qt.c

   163	
   164	static int mi0283qt_probe(struct spi_device *spi)
   165	{
   166		struct device *dev = &spi->dev;
   167		struct mipi_dbi *mipi;
   168		struct gpio_desc *dc;
   169		u32 rotation = 0;
   170		int ret;
   171	
   172		mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL);
   173		if (!mipi)
   174			return -ENOMEM;
   175	
   176		mipi->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
   177		if (IS_ERR(mipi->reset)) {
   178			dev_err(dev, "Failed to get gpio 'reset'\n");
   179			return PTR_ERR(mipi->reset);
   180		}
   181	
   182		dc = devm_gpiod_get_optional(dev, "dc", GPIOD_OUT_LOW);
   183		if (IS_ERR(dc)) {
   184			dev_err(dev, "Failed to get gpio 'dc'\n");
   185			return PTR_ERR(dc);
   186		}
   187	
   188		mipi->regulator = devm_regulator_get(dev, "power");
   189		if (IS_ERR(mipi->regulator))
   190			return PTR_ERR(mipi->regulator);
   191	
 > 192		mipi->backlight = devm_drm_of_find_backlight(dev);
   193		if (IS_ERR(mipi->backlight))
   194			return PTR_ERR(mipi->backlight);
   195	
   196		device_property_read_u32(dev, "rotation", &rotation);
   197	
   198		ret = mipi_dbi_spi_init(spi, mipi, dc);
   199		if (ret)
   200			return ret;
   201	
   202		ret = mipi_dbi_init(&spi->dev, mipi, &mi0283qt_pipe_funcs,
   203				    &mi0283qt_driver, &mi0283qt_mode, rotation);
   204		if (ret)
   205			return ret;
   206	
   207		ret = mi0283qt_init(mipi);
   208		if (ret)
   209			return ret;
   210	
   211		/* use devres to fini after drm unregister (drv->remove is before) */
   212		ret = devm_add_action(dev, mi0283qt_fini, mipi);
   213		if (ret) {
   214			mi0283qt_fini(mipi);
   215			return ret;
   216		}
   217	
   218		spi_set_drvdata(spi, mipi);
   219	
   220		return devm_tinydrm_register(&mipi->tinydrm);
   221	}
   222	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 29255 bytes --]

Re: [PATCH v4 3/3] drm/tinydrm: Add the dummy versions of drm_of_find_backlight functions

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 1931 bytes --]

Hi Meghana,

[auto build test WARNING on drm/drm-next]
[also build test WARNING on v4.14-rc2 next-20170929]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Meghana-Madhyastha/drm-tinydrm-drm_of_find_backlight-helper/20170930-122931
base:   git://people.freedesktop.org/~airlied/linux.git drm-next
config: x86_64-randconfig-x017-201739 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   In file included from drivers/gpu//drm/tinydrm/mi0283qt.c:15:0:
   include/drm/drm_of.h:74:1: error: expected identifier or '(' before '{' token
    {
    ^
   include/drm/drm_of.h:80:1: error: expected identifier or '(' before '{' token
    {
    ^
   include/drm/drm_of.h:72:40: warning: 'drm_of_find_backlight' declared 'static' but never defined [-Wunused-function]
    static inline struct backlight_device *drm_of_find_backlight(
                                           ^~~~~~~~~~~~~~~~~~~~~
>> include/drm/drm_of.h:78:40: warning: 'devm_drm_of_find_backlight' used but never defined
    static inline struct backlight_device *devm_drm_of_find_backlight(
                                           ^~~~~~~~~~~~~~~~~~~~~~~~~~

vim +/devm_drm_of_find_backlight +78 include/drm/drm_of.h

    71	
    72	static inline struct backlight_device *drm_of_find_backlight(
    73						struct device *dev);
  > 74	{
    75		return -EINVAL;
    76	}
    77	
  > 78	static inline struct backlight_device *devm_drm_of_find_backlight(
    79							struct device *dev);
    80	{
    81		return -EINVAL;
    82	}
    83	#endif
    84	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 29255 bytes --]

[-- Attachment #3: Type: text/plain, Size: 160 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH v4 3/3] drm/tinydrm: Add the dummy versions of drm_of_find_backlight functions

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 1931 bytes --]

Hi Meghana,

[auto build test WARNING on drm/drm-next]
[also build test WARNING on v4.14-rc2 next-20170929]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Meghana-Madhyastha/drm-tinydrm-drm_of_find_backlight-helper/20170930-122931
base:   git://people.freedesktop.org/~airlied/linux.git drm-next
config: x86_64-randconfig-x017-201739 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   In file included from drivers/gpu//drm/tinydrm/mi0283qt.c:15:0:
   include/drm/drm_of.h:74:1: error: expected identifier or '(' before '{' token
    {
    ^
   include/drm/drm_of.h:80:1: error: expected identifier or '(' before '{' token
    {
    ^
   include/drm/drm_of.h:72:40: warning: 'drm_of_find_backlight' declared 'static' but never defined [-Wunused-function]
    static inline struct backlight_device *drm_of_find_backlight(
                                           ^~~~~~~~~~~~~~~~~~~~~
>> include/drm/drm_of.h:78:40: warning: 'devm_drm_of_find_backlight' used but never defined
    static inline struct backlight_device *devm_drm_of_find_backlight(
                                           ^~~~~~~~~~~~~~~~~~~~~~~~~~

vim +/devm_drm_of_find_backlight +78 include/drm/drm_of.h

    71	
    72	static inline struct backlight_device *drm_of_find_backlight(
    73						struct device *dev);
  > 74	{
    75		return -EINVAL;
    76	}
    77	
  > 78	static inline struct backlight_device *devm_drm_of_find_backlight(
    79							struct device *dev);
    80	{
    81		return -EINVAL;
    82	}
    83	#endif
    84	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 29255 bytes --]

Re: [PATCH v4 3/3] drm/tinydrm: Add the dummy versions of drm_of_find_backlight functions

[Daniel Vetter]

On Sat, Sep 30, 2017 at 01:18:53PM +0800, kbuild test robot wrote:
> Hi Meghana,
> 
> [auto build test WARNING on drm/drm-next]
> [also build test WARNING on v4.14-rc2 next-20170929]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> 
> url:    https://github.com/0day-ci/linux/commits/Meghana-Madhyastha/drm-tinydrm-drm_of_find_backlight-helper/20170930-122931
> base:   git://people.freedesktop.org/~airlied/linux.git drm-next
> config: x86_64-randconfig-x017-201739 (attached as .config)
> compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
> reproduce:
>         # save the attached .config to linux build tree
>         make ARCH=x86_64 
> 
> All warnings (new ones prefixed by >>):
> 
>    In file included from drivers/gpu//drm/tinydrm/mi0283qt.c:15:0:
>    include/drm/drm_of.h:74:1: error: expected identifier or '(' before '{' token
>     {
>     ^
>    include/drm/drm_of.h:80:1: error: expected identifier or '(' before '{' token
>     {
>     ^
>    include/drm/drm_of.h:72:40: warning: 'drm_of_find_backlight' declared 'static' but never defined [-Wunused-function]
>     static inline struct backlight_device *drm_of_find_backlight(
>                                            ^~~~~~~~~~~~~~~~~~~~~
> >> include/drm/drm_of.h:78:40: warning: 'devm_drm_of_find_backlight' used but never defined
>     static inline struct backlight_device *devm_drm_of_find_backlight(

You need to squash the dummy version into the patch that introduces the
first usage, otherwise compilation can fail and break bisecting. And looks
liek this doesn't compile. It takes a bit of playing around until you have
a Kconfig that hits this. Luckily 0day has constructed one for you
already.
-Daniel

>                                            ^~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> vim +/devm_drm_of_find_backlight +78 include/drm/drm_of.h
> 
>     71	
>     72	static inline struct backlight_device *drm_of_find_backlight(
>     73						struct device *dev);
>   > 74	{
>     75		return -EINVAL;
>     76	}
>     77	
>   > 78	static inline struct backlight_device *devm_drm_of_find_backlight(
>     79							struct device *dev);
>     80	{
>     81		return -EINVAL;
>     82	}
>     83	#endif
>     84	
> 
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation



-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
_______________________________________________
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Re: [PATCH v4 3/3] drm/tinydrm: Add the dummy versions of drm_of_find_backlight functions

[Daniel Vetter]

On Sat, Sep 30, 2017 at 01:18:53PM +0800, kbuild test robot wrote:
> Hi Meghana,
> 
> [auto build test WARNING on drm/drm-next]
> [also build test WARNING on v4.14-rc2 next-20170929]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> 
> url:    https://github.com/0day-ci/linux/commits/Meghana-Madhyastha/drm-tinydrm-drm_of_find_backlight-helper/20170930-122931
> base:   git://people.freedesktop.org/~airlied/linux.git drm-next
> config: x86_64-randconfig-x017-201739 (attached as .config)
> compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
> reproduce:
>         # save the attached .config to linux build tree
>         make ARCH=x86_64 
> 
> All warnings (new ones prefixed by >>):
> 
>    In file included from drivers/gpu//drm/tinydrm/mi0283qt.c:15:0:
>    include/drm/drm_of.h:74:1: error: expected identifier or '(' before '{' token
>     {
>     ^
>    include/drm/drm_of.h:80:1: error: expected identifier or '(' before '{' token
>     {
>     ^
>    include/drm/drm_of.h:72:40: warning: 'drm_of_find_backlight' declared 'static' but never defined [-Wunused-function]
>     static inline struct backlight_device *drm_of_find_backlight(
>                                            ^~~~~~~~~~~~~~~~~~~~~
> >> include/drm/drm_of.h:78:40: warning: 'devm_drm_of_find_backlight' used but never defined
>     static inline struct backlight_device *devm_drm_of_find_backlight(

You need to squash the dummy version into the patch that introduces the
first usage, otherwise compilation can fail and break bisecting. And looks
liek this doesn't compile. It takes a bit of playing around until you have
a Kconfig that hits this. Luckily 0day has constructed one for you
already.
-Daniel

>                                            ^~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> vim +/devm_drm_of_find_backlight +78 include/drm/drm_of.h
> 
>     71	
>     72	static inline struct backlight_device *drm_of_find_backlight(
>     73						struct device *dev);
>   > 74	{
>     75		return -EINVAL;
>     76	}
>     77	
>   > 78	static inline struct backlight_device *devm_drm_of_find_backlight(
>     79							struct device *dev);
>     80	{
>     81		return -EINVAL;
>     82	}
>     83	#endif
>     84	
> 
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation



-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch