Re: [PATCH v2 5/7] drm/ltdc: Use the panel-bridge helper.
From: Archit Taneja
Date: Wed May 31 2017 - 04:01:27 EST
Hi Boris,
On 05/31/2017 11:56 AM, Boris Brezillon wrote:
Hi Philippe,
Le Tue, 30 May 2017 16:55:42 +0000,
Philippe CORNU <philippe.cornu@xxxxxx> a Ãcrit :
Hi Eric,
I took your patch for the panel-bridge and it works perfectly in both
DPI mode (panel RGB //) and DSI mode (bridge dw mipi dsi), bravo :-)
I still don't understand how it can work without a call to
drm_bridge_attach() (which is used to link the RGB encoder to the DPI
connector). I'm probably missing something obvious. Maybe someone can
point it out :-).
I think the expectation is that there will be a follow-up patch that
would add bridge support. Philippe had posted a patch for adding bridges
to ltdc before:
https://patchwork.kernel.org/patch/9724835/
He can now redo his patch over Eric's panel-bridge patch-set.
Thanks,
Archit
Thanks,
Boris
~160 lines have been removed from ltdc.c thanks to your panel-bridge code!
Many thanks
Philippe
On 05/11/2017 08:31 PM, Eric Anholt wrote:
Another 100 lines of boilerplate gone. Bridges aren't supported yet,
but will be trivial to add later.
Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
---
Also untested.
drivers/gpu/drm/stm/ltdc.c | 128 +++++----------------------------------------
drivers/gpu/drm/stm/ltdc.h | 2 +-
2 files changed, 13 insertions(+), 117 deletions(-)
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
index a40418cda74a..41a1c5d68f5b 100644
--- a/drivers/gpu/drm/stm/ltdc.c
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -269,11 +269,6 @@ static inline struct ltdc_device *encoder_to_ltdc(struct drm_encoder *enc)
return (struct ltdc_device *)enc->dev->dev_private;
}
-static inline struct ltdc_device *connector_to_ltdc(struct drm_connector *con)
-{
- return (struct ltdc_device *)con->dev->dev_private;
-}
-
static inline enum ltdc_pix_fmt to_ltdc_pixelformat(u32 drm_fmt)
{
enum ltdc_pix_fmt pf;
@@ -815,22 +810,12 @@ static int ltdc_crtc_init(struct drm_device *ddev, struct drm_crtc *crtc)
static void ltdc_rgb_encoder_enable(struct drm_encoder *encoder)
{
- struct ltdc_device *ldev = encoder_to_ltdc(encoder);
-
DRM_DEBUG_DRIVER("\n");
-
- drm_panel_prepare(ldev->panel);
- drm_panel_enable(ldev->panel);
}
static void ltdc_rgb_encoder_disable(struct drm_encoder *encoder)
{
- struct ltdc_device *ldev = encoder_to_ltdc(encoder);
-
DRM_DEBUG_DRIVER("\n");
-
- drm_panel_disable(ldev->panel);
- drm_panel_unprepare(ldev->panel);
}
static const struct drm_encoder_helper_funcs ltdc_rgb_encoder_helper_funcs = {
@@ -863,82 +848,6 @@ static struct drm_encoder *ltdc_rgb_encoder_create(struct drm_device *ddev)
return encoder;
}
-/*
- * DRM_CONNECTOR
- */
-
-static int ltdc_rgb_connector_get_modes(struct drm_connector *connector)
-{
- struct drm_device *ddev = connector->dev;
- struct ltdc_device *ldev = ddev->dev_private;
- int ret = 0;
-
- DRM_DEBUG_DRIVER("\n");
-
- if (ldev->panel)
- ret = drm_panel_get_modes(ldev->panel);
-
- return ret < 0 ? 0 : ret;
-}
-
-static struct drm_connector_helper_funcs ltdc_rgb_connector_helper_funcs = {
- .get_modes = ltdc_rgb_connector_get_modes,
-};
-
-static enum drm_connector_status
-ltdc_rgb_connector_detect(struct drm_connector *connector, bool force)
-{
- struct ltdc_device *ldev = connector_to_ltdc(connector);
-
- return ldev->panel ? connector_status_connected :
- connector_status_disconnected;
-}
-
-static void ltdc_rgb_connector_destroy(struct drm_connector *connector)
-{
- DRM_DEBUG_DRIVER("\n");
-
- drm_connector_unregister(connector);
- drm_connector_cleanup(connector);
-}
-
-static const struct drm_connector_funcs ltdc_rgb_connector_funcs = {
- .dpms = drm_atomic_helper_connector_dpms,
- .fill_modes = drm_helper_probe_single_connector_modes,
- .detect = ltdc_rgb_connector_detect,
- .destroy = ltdc_rgb_connector_destroy,
- .reset = drm_atomic_helper_connector_reset,
- .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
- .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
-};
-
-struct drm_connector *ltdc_rgb_connector_create(struct drm_device *ddev)
-{
- struct drm_connector *connector;
- int err;
-
- connector = devm_kzalloc(ddev->dev, sizeof(*connector), GFP_KERNEL);
- if (!connector) {
- DRM_ERROR("Failed to allocate connector\n");
- return NULL;
- }
-
- connector->polled = DRM_CONNECTOR_POLL_HPD;
-
- err = drm_connector_init(ddev, connector, <dc_rgb_connector_funcs,
- DRM_MODE_CONNECTOR_DPI);
- if (err) {
- DRM_ERROR("Failed to initialize connector\n");
- return NULL;
- }
-
- drm_connector_helper_add(connector, <dc_rgb_connector_helper_funcs);
-
- DRM_DEBUG_DRIVER("RGB connector:%d created\n", connector->base.id);
-
- return connector;
-}
-
static int ltdc_get_caps(struct drm_device *ddev)
{
struct ltdc_device *ldev = ddev->dev_private;
@@ -972,7 +881,7 @@ static int ltdc_get_caps(struct drm_device *ddev)
return 0;
}
-static struct drm_panel *ltdc_get_panel(struct drm_device *ddev)
+static struct drm_bridge *ltdc_get_bridge(struct drm_device *ddev)
{
struct device *dev = ddev->dev;
struct device_node *np = dev->of_node;
@@ -1004,7 +913,10 @@ static struct drm_panel *ltdc_get_panel(struct drm_device *ddev)
}
}
- return panel;
+ if (!panel)
+ return ERR_PTR(-ENODEV);
+
+ return drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DPI);
}
int ltdc_load(struct drm_device *ddev)
@@ -1014,7 +926,6 @@ int ltdc_load(struct drm_device *ddev)
struct device *dev = ddev->dev;
struct device_node *np = dev->of_node;
struct drm_encoder *encoder;
- struct drm_connector *connector = NULL;
struct drm_crtc *crtc;
struct reset_control *rstc;
struct resource res;
@@ -1022,8 +933,8 @@ int ltdc_load(struct drm_device *ddev)
DRM_DEBUG_DRIVER("\n");
- ldev->panel = ltdc_get_panel(ddev);
- if (!ldev->panel)
+ ldev->bridge = ltdc_get_bridge(ddev);
+ if (!ldev->bridge)
return -EPROBE_DEFER;
rstc = of_reset_control_get(np, NULL);
@@ -1082,28 +993,13 @@ int ltdc_load(struct drm_device *ddev)
DRM_INFO("ltdc hw version 0x%08x - ready\n", ldev->caps.hw_version);
- if (ldev->panel) {
+ if (ldev->bridge) {
encoder = ltdc_rgb_encoder_create(ddev);
if (!encoder) {
DRM_ERROR("Failed to create RGB encoder\n");
ret = -EINVAL;
goto err;
}
-
- connector = ltdc_rgb_connector_create(ddev);
- if (!connector) {
- DRM_ERROR("Failed to create RGB connector\n");
- ret = -EINVAL;
- goto err;
- }
-
- ret = drm_mode_connector_attach_encoder(connector, encoder);
- if (ret) {
- DRM_ERROR("Failed to attach connector to encoder\n");
- goto err;
- }
-
- drm_panel_attach(ldev->panel, connector);
}
crtc = devm_kzalloc(dev, sizeof(*crtc), GFP_KERNEL);
@@ -1130,8 +1026,8 @@ int ltdc_load(struct drm_device *ddev)
return 0;
err:
- if (ldev->panel)
- drm_panel_detach(ldev->panel);
+ if (ldev->bridge)
+ drm_panel_bridge_remove(ldev->bridge);
clk_disable_unprepare(ldev->pixel_clk);
@@ -1146,8 +1042,8 @@ void ltdc_unload(struct drm_device *ddev)
drm_vblank_cleanup(ddev);
- if (ldev->panel)
- drm_panel_detach(ldev->panel);
+ if (ldev->bridge)
+ drm_panel_bridge_remove(ldev->bridge);
clk_disable_unprepare(ldev->pixel_clk);
}
diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h
index d7a9c736ac1e..d78cb0dd3200 100644
--- a/drivers/gpu/drm/stm/ltdc.h
+++ b/drivers/gpu/drm/stm/ltdc.h
@@ -24,7 +24,7 @@ struct ltdc_device {
struct drm_fbdev_cma *fbdev;
void __iomem *regs;
struct clk *pixel_clk; /* lcd pixel clock */
- struct drm_panel *panel;
+ struct drm_bridge *bridge;
struct mutex err_lock; /* protecting error_status */
struct ltdc_caps caps;
u32 clut[256]; /* color look up table */
--
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