[PATCH] drm/panel: simple: Doxygenize 'struct panel_desc'; rename a few functions

[PATCH] drm/panel: simple: Doxygenize 'struct panel_desc'; rename a few functions

[Douglas Anderson]

This attempts to address outstanding review feedback from commit
b8a2948fa2b3 ("drm/panel: simple: Add ability to override typical
timing").  Specifically:

* It was requested that I document (in the structure definition) that
  the device tree override had no effect if 'struct drm_display_mode'
  was used in the panel description.  I have provided full Doxygen
  comments for 'struct panel_desc' to accomplish that.
* panel_simple_get_fixed_modes() was thought to be a confusing name,
  so it has been renamed to panel_simple_get_display_modes().
* panel_simple_parse_override_mode() was thought to be better named as
  panel_simple_parse_panel_timing_node().

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
NOTES:
- I have not addressed the suggestion of doing 'bool has_override =
  panel->override_mode.type != 0;'.  As per my reply on the mailing
  list I think the convention in this file is to rely on implicit
  conversions from int to bool.
- Sam said that there was still something that he didn't understand
  with regards to the flags.  Sam: if this is something that needs to
  be addressed, please yell.

 drivers/gpu/drm/panel/panel-simple.c | 28 ++++++++++++++++++++++------
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index a50871c6836b..f3c0e203f40f 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -38,6 +38,22 @@
 #include <drm/drm_mipi_dsi.h>
 #include <drm/drm_panel.h>
 
+/**
+ * @modes: Pointer to array of fixed modes appropriate for this panel.  If
+ *         only one mode then this can just be the address of this the mode.
+ *         NOTE: cannot be used with "timings" and also if this is specified
+ *         then you cannot override the mode in the device tree.
+ * @num_modes: Number of elements in modes array.
+ * @timings: Pointer to array of display timings.  NOTE: cannot be used with
+ *           "modes" and also these will be used to validate a device tree
+ *           override if one is present.
+ * @num_timings: Number of elements in timings array.
+ * @bpc: Bits per color.
+ * @size: Structure containing the physical size of this panel.
+ * @delay: Structure containing various delay values for this panel.
+ * @bus_format: See MEDIA_BUS_FMT_... defines.
+ * @bus_flags: See DRM_BUS_FLAG_... defines.
+ */
 struct panel_desc {
 	const struct drm_display_mode *modes;
 	unsigned int num_modes;
@@ -135,7 +151,7 @@ static unsigned int panel_simple_get_timings_modes(struct panel_simple *panel)
 	return num;
 }
 
-static unsigned int panel_simple_get_fixed_modes(struct panel_simple *panel)
+static unsigned int panel_simple_get_display_modes(struct panel_simple *panel)
 {
 	struct drm_connector *connector = panel->base.connector;
 	struct drm_device *drm = panel->base.drm;
@@ -199,7 +215,7 @@ static int panel_simple_get_non_edid_modes(struct panel_simple *panel)
 	 */
 	WARN_ON(panel->desc->num_timings && panel->desc->num_modes);
 	if (num == 0)
-		num = panel_simple_get_fixed_modes(panel);
+		num = panel_simple_get_display_modes(panel);
 
 	connector->display_info.bpc = panel->desc->bpc;
 	connector->display_info.width_mm = panel->desc->size.width;
@@ -351,9 +367,9 @@ static const struct drm_panel_funcs panel_simple_funcs = {
 #define PANEL_SIMPLE_BOUNDS_CHECK(to_check, bounds, field) \
 	(to_check->field.typ >= bounds->field.min && \
 	 to_check->field.typ <= bounds->field.max)
-static void panel_simple_parse_override_mode(struct device *dev,
-					     struct panel_simple *panel,
-					     const struct display_timing *ot)
+static void panel_simple_parse_panel_timing_node(struct device *dev,
+						 struct panel_simple *panel,
+						 const struct display_timing *ot)
 {
 	const struct panel_desc *desc = panel->desc;
 	struct videomode vm;
@@ -446,7 +462,7 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 	}
 
 	if (!of_get_display_timing(dev->of_node, "panel-timing", &dt))
-		panel_simple_parse_override_mode(dev, panel, &dt);
+		panel_simple_parse_panel_timing_node(dev, panel, &dt);
 
 	drm_panel_init(&panel->base);
 	panel->base.dev = dev;
-- 
2.22.0.510.g264f2c817a-goog

Re: [PATCH] drm/panel: simple: Doxygenize 'struct panel_desc'; rename a few functions

[Sam Ravnborg]

Hi Doug.

On Fri, Jul 12, 2019 at 09:33:33AM -0700, Douglas Anderson wrote:
> This attempts to address outstanding review feedback from commit
> b8a2948fa2b3 ("drm/panel: simple: Add ability to override typical
> timing").  Specifically:
> 
> * It was requested that I document (in the structure definition) that
>   the device tree override had no effect if 'struct drm_display_mode'
>   was used in the panel description.  I have provided full Doxygen
>   comments for 'struct panel_desc' to accomplish that.
> * panel_simple_get_fixed_modes() was thought to be a confusing name,
>   so it has been renamed to panel_simple_get_display_modes().
> * panel_simple_parse_override_mode() was thought to be better named as
>   panel_simple_parse_panel_timing_node().
> 
> Suggested-by: Sam Ravnborg <sam@ravnborg.org>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>

Thanks.

I updated the $subject to:
    drm/panel: simple: document panel_desc; rename a few functions

And pushed out to drm-misc-next.

> - Sam said that there was still something that he didn't understand
>   with regards to the flags.  Sam: if this is something that needs to
>   be addressed, please yell.

Need to re-visit this later when I have familiarized myself with
the new yaml syntax and what impact any potential changes may have on
the panel drivers.
So for now we leave it as is.

	Sam

Re: [PATCH] drm/panel: simple: Doxygenize 'struct panel_desc'; rename a few functions

[Sam Ravnborg]

Hi Doug.

On Wed, Jul 17, 2019 at 07:33:17PM +0200, Sam Ravnborg wrote:
> Hi Doug.
> 
> On Fri, Jul 12, 2019 at 09:33:33AM -0700, Douglas Anderson wrote:
> > This attempts to address outstanding review feedback from commit
> > b8a2948fa2b3 ("drm/panel: simple: Add ability to override typical
> > timing").  Specifically:
> > 
> > * It was requested that I document (in the structure definition) that
> >   the device tree override had no effect if 'struct drm_display_mode'
> >   was used in the panel description.  I have provided full Doxygen
> >   comments for 'struct panel_desc' to accomplish that.
> > * panel_simple_get_fixed_modes() was thought to be a confusing name,
> >   so it has been renamed to panel_simple_get_display_modes().
> > * panel_simple_parse_override_mode() was thought to be better named as
> >   panel_simple_parse_panel_timing_node().
> > 
> > Suggested-by: Sam Ravnborg <sam@ravnborg.org>
> > Signed-off-by: Douglas Anderson <dianders@chromium.org>
> 
> Thanks.
> 
> I updated the $subject to:
>     drm/panel: simple: document panel_desc; rename a few functions
> 
> And pushed out to drm-misc-next.

I see the following error printed at each boot:

    /panel: could not find node 'panel-timing'

The error originates from this snip (from panel-simple.c):

       if (!of_get_display_timing(dev->of_node, "panel-timing", &dt))
                panel_simple_parse_panel_timing_node(dev, panel, &dt);

of_get_display_timing() returns -2 (-ENOENT).

In the setup I use there is no panel-timing node as the timing specified
in panel-simple.c is fine.
This is the typical setup - and there should not in the normal case
be printed error messages like this during boot.

Will you please take a look at this.

	Sam

Re: [PATCH] drm/panel: simple: Doxygenize 'struct panel_desc'; rename a few functions

[Doug Anderson]

Hi,

On Sun, Jul 21, 2019 at 2:38 AM Sam Ravnborg <sam@ravnborg.org> wrote:
>
> Hi Doug.
>
> On Wed, Jul 17, 2019 at 07:33:17PM +0200, Sam Ravnborg wrote:
> > Hi Doug.
> >
> > On Fri, Jul 12, 2019 at 09:33:33AM -0700, Douglas Anderson wrote:
> > > This attempts to address outstanding review feedback from commit
> > > b8a2948fa2b3 ("drm/panel: simple: Add ability to override typical
> > > timing").  Specifically:
> > >
> > > * It was requested that I document (in the structure definition) that
> > >   the device tree override had no effect if 'struct drm_display_mode'
> > >   was used in the panel description.  I have provided full Doxygen
> > >   comments for 'struct panel_desc' to accomplish that.
> > > * panel_simple_get_fixed_modes() was thought to be a confusing name,
> > >   so it has been renamed to panel_simple_get_display_modes().
> > > * panel_simple_parse_override_mode() was thought to be better named as
> > >   panel_simple_parse_panel_timing_node().
> > >
> > > Suggested-by: Sam Ravnborg <sam@ravnborg.org>
> > > Signed-off-by: Douglas Anderson <dianders@chromium.org>
> >
> > Thanks.
> >
> > I updated the $subject to:
> >     drm/panel: simple: document panel_desc; rename a few functions
> >
> > And pushed out to drm-misc-next.
>
> I see the following error printed at each boot:
>
>     /panel: could not find node 'panel-timing'
>
> The error originates from this snip (from panel-simple.c):
>
>        if (!of_get_display_timing(dev->of_node, "panel-timing", &dt))
>                 panel_simple_parse_panel_timing_node(dev, panel, &dt);
>
> of_get_display_timing() returns -2 (-ENOENT).
>
> In the setup I use there is no panel-timing node as the timing specified
> in panel-simple.c is fine.
> This is the typical setup - and there should not in the normal case
> be printed error messages like this during boot.
>
> Will you please take a look at this.

Breadcrumbs: series has been posted to address this.  PTAL.

https://lkml.kernel.org/r/20190722182439.44844-1-dianders@chromium.org


-Doug