Re: [PATCH v3 1/2] drm/probe-helper: Add helper for drm_helper_probe_single_connector_modes()

From: Dmitry Baryshkov
Date: Wed Jun 01 2022 - 16:47:22 EST


On 12/05/2022 01:58, Douglas Anderson wrote:
The drm_helper_probe_single_connector_modes() is a bit long. Let's
break a chunk off to update and validate modes. This helps avoid one
goto and also will allow us to more easily call the helper a second
time in a future patch without adding looping or another goto.

This change is intended to be a no-op change--just code movement.

Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
Reviewed-by: Thomas Zimmermann <tzimmermann@xxxxxxx>

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>

---

Changes in v3:
- Removed WARN_ON

Changes in v2:
- Two underscores for __drm_helper_update_and_validate().
- Return err and use WARN_ON instead of returning a bool.

drivers/gpu/drm/drm_probe_helper.c | 106 ++++++++++++++++-------------
1 file changed, 60 insertions(+), 46 deletions(-)

diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
index 682359512996..2570d47e7eab 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -354,6 +354,61 @@ drm_helper_probe_detect(struct drm_connector *connector,
}
EXPORT_SYMBOL(drm_helper_probe_detect);
+static int __drm_helper_update_and_validate(struct drm_connector *connector,
+ uint32_t maxX, uint32_t maxY,
+ struct drm_modeset_acquire_ctx *ctx)
+{
+ struct drm_device *dev = connector->dev;
+ struct drm_display_mode *mode;
+ int mode_flags = 0;
+ int ret;
+
+ drm_connector_list_update(connector);
+
+ if (connector->interlace_allowed)
+ mode_flags |= DRM_MODE_FLAG_INTERLACE;
+ if (connector->doublescan_allowed)
+ mode_flags |= DRM_MODE_FLAG_DBLSCAN;
+ if (connector->stereo_allowed)
+ mode_flags |= DRM_MODE_FLAG_3D_MASK;
+
+ list_for_each_entry(mode, &connector->modes, head) {
+ if (mode->status != MODE_OK)
+ continue;
+
+ mode->status = drm_mode_validate_driver(dev, mode);
+ if (mode->status != MODE_OK)
+ continue;
+
+ mode->status = drm_mode_validate_size(mode, maxX, maxY);
+ if (mode->status != MODE_OK)
+ continue;
+
+ mode->status = drm_mode_validate_flag(mode, mode_flags);
+ if (mode->status != MODE_OK)
+ continue;
+
+ ret = drm_mode_validate_pipeline(mode, connector, ctx,
+ &mode->status);
+ if (ret) {
+ drm_dbg_kms(dev,
+ "drm_mode_validate_pipeline failed: %d\n",
+ ret);
+
+ if (drm_WARN_ON_ONCE(dev, ret != -EDEADLK))
+ mode->status = MODE_ERROR;
+ else
+ return -EDEADLK;
+ }
+
+ if (mode->status != MODE_OK)
+ continue;
+ mode->status = drm_mode_validate_ycbcr420(mode, connector);
+ }
+
+ return 0;
+}
+
/**
* drm_helper_probe_single_connector_modes - get complete set of display modes
* @connector: connector to probe
@@ -421,7 +476,6 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
const struct drm_connector_helper_funcs *connector_funcs =
connector->helper_private;
int count = 0, ret;
- int mode_flags = 0;
bool verbose_prune = true;
enum drm_connector_status old_status;
struct drm_modeset_acquire_ctx ctx;
@@ -519,52 +573,12 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
connector->status == connector_status_unknown))
count = drm_add_modes_noedid(connector, 1024, 768);
count += drm_helper_probe_add_cmdline_mode(connector);
- if (count == 0)
- goto prune;
-
- drm_connector_list_update(connector);
-
- if (connector->interlace_allowed)
- mode_flags |= DRM_MODE_FLAG_INTERLACE;
- if (connector->doublescan_allowed)
- mode_flags |= DRM_MODE_FLAG_DBLSCAN;
- if (connector->stereo_allowed)
- mode_flags |= DRM_MODE_FLAG_3D_MASK;
-
- list_for_each_entry(mode, &connector->modes, head) {
- if (mode->status != MODE_OK)
- continue;
-
- mode->status = drm_mode_validate_driver(dev, mode);
- if (mode->status != MODE_OK)
- continue;
-
- mode->status = drm_mode_validate_size(mode, maxX, maxY);
- if (mode->status != MODE_OK)
- continue;
-
- mode->status = drm_mode_validate_flag(mode, mode_flags);
- if (mode->status != MODE_OK)
- continue;
-
- ret = drm_mode_validate_pipeline(mode, connector, &ctx,
- &mode->status);
- if (ret) {
- drm_dbg_kms(dev,
- "drm_mode_validate_pipeline failed: %d\n",
- ret);
-
- if (drm_WARN_ON_ONCE(dev, ret != -EDEADLK)) {
- mode->status = MODE_ERROR;
- } else {
- drm_modeset_backoff(&ctx);
- goto retry;
- }
+ if (count != 0) {
+ ret = __drm_helper_update_and_validate(connector, maxX, maxY, &ctx);
+ if (ret == -EDEADLK) {
+ drm_modeset_backoff(&ctx);
+ goto retry;
}
-
- if (mode->status != MODE_OK)
- continue;
- mode->status = drm_mode_validate_ycbcr420(mode, connector);
}
prune:


--
With best wishes
Dmitry