[RFC 3/4] drm: tegra: use the Common Display Framework

Alexandre Courbot
2013-01-30T03:03:03Z

Make the tegra-drm driver use the Common Display Framework, letting it
control the panel state according to the DPMS status.

A "nvidia,panel" property is added to the output node of the Tegra DC
that references the panel connected to a given output.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
---
.../bindings/gpu/nvidia,tegra20-host1x.txt | 2 +
drivers/gpu/drm/tegra/drm.h | 16 +++
drivers/gpu/drm/tegra/output.c | 118 ++++++++++++++++++++-
3 files changed, 134 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/gpu/nvidia,tegra20-host1x.txt b/Documentation/devicetree/bindings/gpu/nvidia,tegra20-host1x.txt
index b4fa934..9c65e8e 100644
--- a/Documentation/devicetree/bindings/gpu/nvidia,tegra20-host1x.txt
+++ b/Documentation/devicetree/bindings/gpu/nvidia,tegra20-host1x.txt
@@ -67,6 +67,7 @@ of the following host1x client modules:
- nvidia,ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing
- nvidia,hpd-gpio: specifies a GPIO used for hotplug detection
- nvidia,edid: supplies a binary EDID blob
+ - nvidia,panel: phandle of a display entity connected to this output

- hdmi: High Definition Multimedia Interface

@@ -81,6 +82,7 @@ of the following host1x client modules:
- nvidia,ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing
- nvidia,hpd-gpio: specifies a GPIO used for hotplug detection
- nvidia,edid: supplies a binary EDID blob
+ - nvidia,panel: phandle of a display entity connected to this output

- tvo: TV encoder output

diff --git a/drivers/gpu/drm/tegra/drm.h b/drivers/gpu/drm/tegra/drm.h
index 741b5dc..5e63c56 100644
--- a/drivers/gpu/drm/tegra/drm.h
+++ b/drivers/gpu/drm/tegra/drm.h
@@ -17,6 +17,7 @@
#include <drm/drm_gem_cma_helper.h>
#include <drm/drm_fb_cma_helper.h>
#include <drm/drm_fixed.h>
+#include <video/display.h>

struct tegra_framebuffer {
struct drm_framebuffer base;
@@ -147,6 +148,9 @@ struct tegra_output {

struct drm_encoder encoder;
struct drm_connector connector;
+ struct display_entity this;
+ struct display_entity *output;
+ struct display_entity_notifier display_notifier;
};

static inline struct tegra_output *encoder_to_output(struct drm_encoder *e)
@@ -159,6 +163,18 @@ static inline struct tegra_output *connector_to_output(struct drm_connector *c)
return container_of(c, struct tegra_output, connector);
}

+static inline
+struct tegra_output *display_entity_to_output(struct display_entity *e)
+{
+ return container_of(e, struct tegra_output, this);
+}
+
+static inline struct tegra_output *
+display_notifier_to_output(struct display_entity_notifier *n)
+{
+ return container_of(n, struct tegra_output, display_notifier);
+}
+
static inline int tegra_output_enable(struct tegra_output *output)
{
if (output && output->ops && output->ops->enable)
diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c
index 8140fc6..d5bf37a 100644
--- a/drivers/gpu/drm/tegra/output.c
+++ b/drivers/gpu/drm/tegra/output.c
@@ -105,6 +105,29 @@ static const struct drm_encoder_funcs encoder_funcs = {

static void tegra_encoder_dpms(struct drm_encoder *encoder, int mode)
{
+ struct tegra_output *output = encoder_to_output(encoder);
+ enum display_entity_state state;
+
+ if (!output->output)
+ return;
+
+ switch (mode) {
+ case DRM_MODE_DPMS_ON:
+ state = DISPLAY_ENTITY_STATE_ON;
+ break;
+ case DRM_MODE_DPMS_STANDBY:
+ case DRM_MODE_DPMS_SUSPEND:
+ state = DISPLAY_ENTITY_STATE_STANDBY;
+ break;
+ case DRM_MODE_DPMS_OFF:
+ state = DISPLAY_ENTITY_STATE_OFF;
+ break;
+ default:
+ dev_warn(output->dev, "unknown DPMS state, ignoring\n");
+ return;
+ }
+
+ display_entity_set_state(output->output, state);
}

static bool tegra_encoder_mode_fixup(struct drm_encoder *encoder,
@@ -129,9 +152,14 @@ static void tegra_encoder_mode_set(struct drm_encoder *encoder,
struct tegra_output *output = encoder_to_output(encoder);
int err;

- err = tegra_output_enable(output);
+ if (output->output)
+ err = display_entity_set_state(output->output,
+ DISPLAY_ENTITY_STATE_ON);
+ else
+ err = tegra_output_enable(output);
+
if (err < 0)
- dev_err(encoder->dev->dev, "tegra_output_enable(): %d\n", err);
+ dev_err(encoder->dev->dev, "cannot enable output: %d\n", err);
}

static const struct drm_encoder_helper_funcs encoder_helper_funcs = {
@@ -185,6 +213,69 @@ int tegra_output_parse_dt(struct tegra_output *output)
return 0;
}

+static int display_notify_callback(struct display_entity_notifier *notifier,
+ struct display_entity *entity, int event)
+{
+ struct tegra_output *output = display_notifier_to_output(notifier);
+ struct device_node *pnode;
+
+ switch (event) {
+ case DISPLAY_ENTITY_NOTIFIER_CONNECT:
+ if (output->output)
+ break;
+
+ pnode = of_parse_phandle(output->of_node, "nvidia,panel", 0);
+ if (!pnode)
+ break;
+
+ if (entity->dev && entity->dev->of_node == pnode) {
+ dev_dbg(output->dev, "connecting panel\n");
+ output->output = display_entity_get(entity);
+ display_entity_connect(&output->this, output->output);
+ }
+ of_node_put(pnode);
+
+ break;
+
+ case DISPLAY_ENTITY_NOTIFIER_DISCONNECT:
+ if (!output->output || output->output != entity)
+ break;
+
+ dev_dbg(output->dev, "disconnecting panel\n");
+ display_entity_disconnect(&output->this, output->output);
+ output->output = NULL;
+ display_entity_put(&output->this);
+
+ break;
+
+ default:
+ dev_dbg(output->dev, "unhandled display event\n");
+ break;
+ }
+
+ return 0;
+}
+
+static int tegra_output_set_stream(struct display_entity *entity,
+ enum display_entity_stream_state state)
+{
+ struct tegra_output *output = display_entity_to_output(entity);
+
+ switch (state) {
+ case DISPLAY_ENTITY_STATE_OFF:
+ case DISPLAY_ENTITY_STATE_STANDBY:
+ return output->ops->disable(output);
+ case DISPLAY_ENTITY_STATE_ON:
+ return output->ops->enable(output);
+ }
+
+ return 0;
+}
+
+static struct display_entity_video_ops tegra_output_video_ops = {
+ .set_stream = tegra_output_set_stream,
+};
+
int tegra_output_init(struct drm_device *drm, struct tegra_output *output)
{
int connector, encoder, err;
@@ -250,6 +341,23 @@ int tegra_output_init(struct drm_device *drm, struct tegra_output *output)

output->encoder.possible_crtcs = 0x3;

+ /* register display entity */
+ memset(&output->this, 0, sizeof(output->this));
+ output->this.dev = drm->dev;
+ output->this.ops.video = &tegra_output_video_ops;
+ err = display_entity_register(&output->this);
+ if (err) {
+ dev_err(output->dev, "cannot register display entity\n");
+ return err;
+ }
+
+ /* register display notifier */
+ output->display_notifier.dev = NULL;
+ output->display_notifier.notify = display_notify_callback;
+ err = display_entity_register_notifier(&output->display_notifier);
+ if (err)
+ return err;
+
return 0;

free_hpd:
@@ -260,6 +368,12 @@ free_hpd:

int tegra_output_exit(struct tegra_output *output)
{
+ if (output->output)
+ display_entity_put(output->output);
+
+ display_entity_unregister_notifier(&output->display_notifier);
+ display_entity_unregister(&output->this);
+
if (gpio_is_valid(output->hpd_gpio)) {
free_irq(output->hpd_irq, output);
gpio_free(output->hpd_gpio);
--
1.8.1.1