diff mbox series

[v6,6/6] drm/tegra: output: rgb: Wrap directly-connected panel into DRM bridge

Message ID 20200609132855.20975-7-digetx@gmail.com
State Superseded
Headers show
Series Support DRM bridges on NVIDIA Tegra | expand

Commit Message

Dmitry Osipenko June 9, 2020, 1:28 p.m. UTC
Currently Tegra DRM driver manually manages display panel, but this
management could be moved out into DRM core if we'll wrap panel into
DRM bridge. This patch wraps RGB panel into a DRM bridge and removes
manual handling of the panel from the RGB output code.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 drivers/gpu/drm/tegra/rgb.c | 53 +++++++++++++------------------------
 1 file changed, 18 insertions(+), 35 deletions(-)

Comments

kernel test robot June 12, 2020, 9:23 p.m. UTC | #1
Hi Dmitry,

I love your patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on next-20200612]
[cannot apply to tegra/for-next robh/for-next v5.7]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Dmitry-Osipenko/Support-DRM-bridges-on-NVIDIA-Tegra/20200609-213026
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git abfbb29297c27e3f101f348dc9e467b0fe70f919
config: arm64-randconfig-r026-20200612 (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 3b43f006294971b8049d4807110032169780e5b8)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>, old ones prefixed by <<):

>> drivers/gpu/drm/tegra/rgb.c:100:48: warning: unused variable 'tegra_rgb_connector_helper_funcs' [-Wunused-const-variable]
static const struct drm_connector_helper_funcs tegra_rgb_connector_helper_funcs = {
^
1 warning generated.

vim +/tegra_rgb_connector_helper_funcs +100 drivers/gpu/drm/tegra/rgb.c

3b0e58554873d1 Thierry Reding 2014-12-16   99  
3b0e58554873d1 Thierry Reding 2014-12-16 @100  static const struct drm_connector_helper_funcs tegra_rgb_connector_helper_funcs = {
3b0e58554873d1 Thierry Reding 2014-12-16  101  	.get_modes = tegra_output_connector_get_modes,
3b0e58554873d1 Thierry Reding 2014-12-16  102  	.mode_valid = tegra_rgb_connector_mode_valid,
3b0e58554873d1 Thierry Reding 2014-12-16  103  };
3b0e58554873d1 Thierry Reding 2014-12-16  104  

:::::: The code at line 100 was first introduced by commit
:::::: 3b0e58554873d1034beef737f15c7aa46492ff98 drm/tegra: rgb: Demidlayer

:::::: TO: Thierry Reding <treding@nvidia.com>
:::::: CC: Thierry Reding <treding@nvidia.com>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Dmitry Osipenko June 12, 2020, 9:53 p.m. UTC | #2
13.06.2020 00:23, kernel test robot пишет:
> Hi Dmitry,
> 
> I love your patch! Perhaps something to improve:
> 
> [auto build test WARNING on linus/master]
> [also build test WARNING on next-20200612]
> [cannot apply to tegra/for-next robh/for-next v5.7]
> [if your patch is applied to the wrong git tree, please drop us a note to help
> improve the system. BTW, we also suggest to use '--base' option to specify the
> base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
> 
> url:    https://github.com/0day-ci/linux/commits/Dmitry-Osipenko/Support-DRM-bridges-on-NVIDIA-Tegra/20200609-213026
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git abfbb29297c27e3f101f348dc9e467b0fe70f919
> config: arm64-randconfig-r026-20200612 (attached as .config)
> compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 3b43f006294971b8049d4807110032169780e5b8)

Interestingly, GCC doesn't report this warning.

> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install arm64 cross compiling tool for clang build
>         # apt-get install binutils-aarch64-linux-gnu
>         # save the attached .config to linux build tree
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
> 
> All warnings (new ones prefixed by >>, old ones prefixed by <<):
> 
>>> drivers/gpu/drm/tegra/rgb.c:100:48: warning: unused variable 'tegra_rgb_connector_helper_funcs' [-Wunused-const-variable]
> static const struct drm_connector_helper_funcs tegra_rgb_connector_helper_funcs = {
> ^
> 1 warning generated.


There are two unused structs in the code and one is referenced by the
other, I'll remove the unused structs in v7.
diff mbox series

Patch

diff --git a/drivers/gpu/drm/tegra/rgb.c b/drivers/gpu/drm/tegra/rgb.c
index 9a7024ec96bc..a4c5a6066c54 100644
--- a/drivers/gpu/drm/tegra/rgb.c
+++ b/drivers/gpu/drm/tegra/rgb.c
@@ -8,7 +8,6 @@ 
 
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge_connector.h>
-#include <drm/drm_panel.h>
 #include <drm/drm_simple_kms_helper.h>
 
 #include "drm.h"
@@ -86,15 +85,6 @@  static void tegra_dc_write_regs(struct tegra_dc *dc,
 		tegra_dc_writel(dc, table[i].value, table[i].offset);
 }
 
-static const struct drm_connector_funcs tegra_rgb_connector_funcs = {
-	.reset = drm_atomic_helper_connector_reset,
-	.detect = tegra_output_connector_detect,
-	.fill_modes = drm_helper_probe_single_connector_modes,
-	.destroy = tegra_output_connector_destroy,
-	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
-	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
-};
-
 static enum drm_mode_status
 tegra_rgb_connector_mode_valid(struct drm_connector *connector,
 			       struct drm_display_mode *mode)
@@ -117,14 +107,8 @@  static void tegra_rgb_encoder_disable(struct drm_encoder *encoder)
 	struct tegra_output *output = encoder_to_output(encoder);
 	struct tegra_rgb *rgb = to_rgb(output);
 
-	if (output->panel)
-		drm_panel_disable(output->panel);
-
 	tegra_dc_write_regs(rgb->dc, rgb_disable, ARRAY_SIZE(rgb_disable));
 	tegra_dc_commit(rgb->dc);
-
-	if (output->panel)
-		drm_panel_unprepare(output->panel);
 }
 
 static void tegra_rgb_encoder_enable(struct drm_encoder *encoder)
@@ -133,9 +117,6 @@  static void tegra_rgb_encoder_enable(struct drm_encoder *encoder)
 	struct tegra_rgb *rgb = to_rgb(output);
 	u32 value;
 
-	if (output->panel)
-		drm_panel_prepare(output->panel);
-
 	tegra_dc_write_regs(rgb->dc, rgb_enable, ARRAY_SIZE(rgb_enable));
 
 	value = DE_SELECT_ACTIVE | DE_CONTROL_NORMAL;
@@ -157,9 +138,6 @@  static void tegra_rgb_encoder_enable(struct drm_encoder *encoder)
 	tegra_dc_writel(rgb->dc, value, DC_DISP_SHIFT_CLOCK_OPTIONS);
 
 	tegra_dc_commit(rgb->dc);
-
-	if (output->panel)
-		drm_panel_enable(output->panel);
 }
 
 static int
@@ -278,6 +256,23 @@  int tegra_dc_rgb_init(struct drm_device *drm, struct tegra_dc *dc)
 	drm_encoder_helper_add(&output->encoder,
 			       &tegra_rgb_encoder_helper_funcs);
 
+	/*
+	 * Wrap directly-connected panel into DRM bridge in order to let
+	 * DRM core to handle panel for us.
+	 */
+	if (output->panel) {
+		output->bridge = devm_drm_panel_bridge_add(output->dev,
+							   output->panel);
+		if (IS_ERR(output->bridge)) {
+			dev_err(output->dev,
+				"failed to wrap panel into bridge: %pe\n",
+				output->bridge);
+			return PTR_ERR(output->bridge);
+		}
+
+		output->panel = NULL;
+	}
+
 	/*
 	 * Tegra devices that have LVDS panel utilize LVDS encoder bridge
 	 * for converting up to 28 LCD LVTTL lanes into 5/4 LVDS lanes that
@@ -292,8 +287,7 @@  int tegra_dc_rgb_init(struct drm_device *drm, struct tegra_dc *dc)
 	 * Newer device-trees utilize LVDS encoder bridge, which provides
 	 * us with a connector and handles the display panel.
 	 *
-	 * For older device-trees we fall back to our own connector and use
-	 * nvidia,panel phandle.
+	 * For older device-trees we wrapped panel into the panel-bridge.
 	 */
 	if (output->bridge) {
 		err = drm_bridge_attach(&output->encoder, output->bridge,
@@ -313,17 +307,6 @@  int tegra_dc_rgb_init(struct drm_device *drm, struct tegra_dc *dc)
 		}
 
 		drm_connector_attach_encoder(connector, &output->encoder);
-	} else {
-		drm_connector_init(drm, &output->connector,
-				   &tegra_rgb_connector_funcs,
-				   DRM_MODE_CONNECTOR_LVDS);
-		drm_connector_helper_add(&output->connector,
-					 &tegra_rgb_connector_helper_funcs);
-		output->connector.dpms = DRM_MODE_DPMS_OFF;
-
-		drm_connector_attach_encoder(&output->connector,
-					     &output->encoder);
-		drm_connector_register(&output->connector);
 	}
 
 	err = tegra_output_init(drm, output);