From: Steve Longerbeam <[email protected]>
Add support for reading EDID over Display Data Channel. If no DDC
adapter is available, falls back to hardcoded EDID or display-timings
node as before.
Signed-off-by: Steve Longerbeam <[email protected]>
Signed-off-by: Akshay Bhat <[email protected]>
Acked-by: Philipp Zabel <[email protected]>
---
Hi Philipp,
I have addressed all your comments on v2 Patch.
Thanks,
Akshay
v3:
Move ddc_node pointer definition
Warn and perform a probe deferral on failing to get ddc i2c adapter by node
v2:
Rebase to 4.6-rc5
Add check for channel->panel before fallback to display-timings node
drivers/gpu/drm/imx/imx-ldb.c | 42 ++++++++++++++++++++++++++++++++++--------
1 file changed, 34 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c
index a58eee5..f506e8d 100644
--- a/drivers/gpu/drm/imx/imx-ldb.c
+++ b/drivers/gpu/drm/imx/imx-ldb.c
@@ -59,6 +59,7 @@ struct imx_ldb_channel {
struct drm_encoder encoder;
struct drm_panel *panel;
struct device_node *child;
+ struct i2c_adapter *ddc;
int chno;
void *edid;
int edid_len;
@@ -107,6 +108,9 @@ static int imx_ldb_connector_get_modes(struct drm_connector *connector)
return num_modes;
}
+ if (!imx_ldb_ch->edid && imx_ldb_ch->ddc)
+ imx_ldb_ch->edid = drm_get_edid(connector, imx_ldb_ch->ddc);
+
if (imx_ldb_ch->edid) {
drm_mode_connector_update_edid_property(connector,
imx_ldb_ch->edid);
@@ -553,6 +557,7 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
for_each_child_of_node(np, child) {
struct imx_ldb_channel *channel;
+ struct device_node *ddc_node;
struct device_node *port;
ret = of_property_read_u32(child, "reg", &i);
@@ -595,14 +600,34 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
}
}
- edidp = of_get_property(child, "edid", &channel->edid_len);
- if (edidp) {
- channel->edid = kmemdup(edidp, channel->edid_len,
- GFP_KERNEL);
- } else if (!channel->panel) {
- ret = of_get_drm_display_mode(child, &channel->mode, 0);
- if (!ret)
- channel->mode_valid = 1;
+ ddc_node = of_parse_phandle(child, "ddc-i2c-bus", 0);
+ if (ddc_node) {
+ channel->ddc = of_find_i2c_adapter_by_node(ddc_node);
+ of_node_put(ddc_node);
+ if (!channel->ddc) {
+ dev_warn(dev, "failed to get ddc i2c adapter\n");
+ return -EPROBE_DEFER;
+ }
+ }
+
+ if (!channel->ddc) {
+ /* if no DDC available, fallback to hardcoded EDID */
+ dev_dbg(dev, "no ddc available\n");
+
+ edidp = of_get_property(child, "edid",
+ &channel->edid_len);
+ if (edidp) {
+ channel->edid = kmemdup(edidp,
+ channel->edid_len,
+ GFP_KERNEL);
+ } else if (!channel->panel) {
+ /* fallback to display-timings node */
+ ret = of_get_drm_display_mode(child,
+ &channel->mode,
+ 0);
+ if (!ret)
+ channel->mode_valid = 1;
+ }
}
channel->bus_format = of_get_bus_format(dev, child);
@@ -647,6 +672,7 @@ static void imx_ldb_unbind(struct device *dev, struct device *master,
channel->encoder.funcs->destroy(&channel->encoder);
kfree(channel->edid);
+ i2c_put_adapter(channel->ddc);
}
}
--
2.8.1
Document the ddc-i2c-bus property used by imx-ldb driver to read EDID
information via I2C interface.
Signed-off-by: Akshay Bhat <[email protected]>
---
v3:
Newly added.
Documentation/devicetree/bindings/display/imx/ldb.txt | 1 +
1 file changed, 1 insertion(+)
diff --git a/Documentation/devicetree/bindings/display/imx/ldb.txt b/Documentation/devicetree/bindings/display/imx/ldb.txt
index 0a175d9..a407462 100644
--- a/Documentation/devicetree/bindings/display/imx/ldb.txt
+++ b/Documentation/devicetree/bindings/display/imx/ldb.txt
@@ -62,6 +62,7 @@ Required properties:
display-timings are used instead.
Optional properties (required if display-timings are used):
+ - ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing
- display-timings : A node that describes the display timings as defined in
Documentation/devicetree/bindings/display/display-timing.txt.
- fsl,data-mapping : should be "spwg" or "jeida"
--
2.8.1
On Wed, Apr 27, 2016 at 04:23:34PM -0400, Akshay Bhat wrote:
> Document the ddc-i2c-bus property used by imx-ldb driver to read EDID
> information via I2C interface.
>
> Signed-off-by: Akshay Bhat <[email protected]>
> ---
>
> v3:
> Newly added.
>
> Documentation/devicetree/bindings/display/imx/ldb.txt | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/Documentation/devicetree/bindings/display/imx/ldb.txt b/Documentation/devicetree/bindings/display/imx/ldb.txt
> index 0a175d9..a407462 100644
> --- a/Documentation/devicetree/bindings/display/imx/ldb.txt
> +++ b/Documentation/devicetree/bindings/display/imx/ldb.txt
> @@ -62,6 +62,7 @@ Required properties:
> display-timings are used instead.
>
> Optional properties (required if display-timings are used):
The required part doesn't make sense if you add this, but...
> + - ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing
Really, this should be part of a connector node since i2c goes from the
i2c controller to a connector and is not part of the display controller.
> - display-timings : A node that describes the display timings as defined in
> Documentation/devicetree/bindings/display/display-timing.txt.
> - fsl,data-mapping : should be "spwg" or "jeida"
> --
> 2.8.1
>
Am Donnerstag, den 28.04.2016, 16:48 -0500 schrieb Rob Herring:
> On Wed, Apr 27, 2016 at 04:23:34PM -0400, Akshay Bhat wrote:
> > Document the ddc-i2c-bus property used by imx-ldb driver to read EDID
> > information via I2C interface.
> >
> > Signed-off-by: Akshay Bhat <[email protected]>
> > ---
> >
> > v3:
> > Newly added.
> >
> > Documentation/devicetree/bindings/display/imx/ldb.txt | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/Documentation/devicetree/bindings/display/imx/ldb.txt b/Documentation/devicetree/bindings/display/imx/ldb.txt
> > index 0a175d9..a407462 100644
> > --- a/Documentation/devicetree/bindings/display/imx/ldb.txt
> > +++ b/Documentation/devicetree/bindings/display/imx/ldb.txt
> > @@ -62,6 +62,7 @@ Required properties:
> > display-timings are used instead.
> >
> > Optional properties (required if display-timings are used):
>
> The required part doesn't make sense if you add this, but...
>
> > + - ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing
>
> Really, this should be part of a connector node since i2c goes from the
> i2c controller to a connector and is not part of the display controller.
If the ddc i2c bus does indeed go through a connector, yes. Would that
warrant a generic "lvds-connector" binding for all those different types
of internal LVDS connectors?
regards
Philipp