| Message ID | 20220913085320.8577-7-johan+linaro@kernel.org (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | drm/msm: probe deferral fixes | expand |
Hi, On Tue, Sep 13, 2022 at 9:58 AM Johan Hovold <johan+linaro@kernel.org> wrote: > > Device-managed resources allocated post component bind must be tied to > the lifetime of the aggregate DRM device or they will not necessarily be > released when binding of the aggregate device is deferred. > > This can lead resource leaks or failure to bind the aggregate device > when binding is later retried and a second attempt to allocate the > resources is made. > > For the DP aux-bus, an attempt to populate the bus a second time will > simply fail ("DP AUX EP device already populated"). > > Fix this by tying the lifetime of the EP device to the DRM device rather > than DP controller platform device. > > Fixes: c3bf8e21b38a ("drm/msm/dp: Add eDP support via aux_bus") > Cc: stable@vger.kernel.org # 5.19 > Signed-off-by: Johan Hovold <johan+linaro@kernel.org> > --- > drivers/gpu/drm/msm/dp/dp_display.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) This seems fine to me as a short term fix until we get the DP AUX populating moved to probe. Reviewed-by: Douglas Anderson <dianders@chromium.org>
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c index ba557328710a..4b0a2d4bb61e 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -1535,6 +1535,11 @@ void msm_dp_debugfs_init(struct msm_dp *dp_display, struct drm_minor *minor) } } +static void of_dp_aux_depopulate_bus_void(void *data) +{ + of_dp_aux_depopulate_bus(data); +} + static int dp_display_get_next_bridge(struct msm_dp *dp) { int rc; @@ -1559,10 +1564,16 @@ static int dp_display_get_next_bridge(struct msm_dp *dp) * panel driver is probed asynchronously but is the best we * can do without a bigger driver reorganization. */ - rc = devm_of_dp_aux_populate_ep_devices(dp_priv->aux); + rc = of_dp_aux_populate_bus(dp_priv->aux, NULL); of_node_put(aux_bus); if (rc) goto error; + + rc = devm_add_action_or_reset(dp->drm_dev->dev, + of_dp_aux_depopulate_bus_void, + dp_priv->aux); + if (rc) + goto error; } else if (dp->is_edp) { DRM_ERROR("eDP aux_bus not found\n"); return -ENODEV;
Device-managed resources allocated post component bind must be tied to the lifetime of the aggregate DRM device or they will not necessarily be released when binding of the aggregate device is deferred. This can lead resource leaks or failure to bind the aggregate device when binding is later retried and a second attempt to allocate the resources is made. For the DP aux-bus, an attempt to populate the bus a second time will simply fail ("DP AUX EP device already populated"). Fix this by tying the lifetime of the EP device to the DRM device rather than DP controller platform device. Fixes: c3bf8e21b38a ("drm/msm/dp: Add eDP support via aux_bus") Cc: stable@vger.kernel.org # 5.19 Signed-off-by: Johan Hovold <johan+linaro@kernel.org> --- drivers/gpu/drm/msm/dp/dp_display.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)