| Message ID | 1476323438-8435-1-git-send-email-mark.yao@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Oct 12, 2016 at 9:50 PM, Mark Yao <mark.yao@rock-chips.com> wrote: > The drm callback ->detect and ->get_modes seems is not power safe, > they may be called when device is power off, do register access on > detect or get_modes will cause system die. > > Here is the path call ->detect before analogix_dp power on > [<ffffff800843babc>] analogix_dp_detect+0x44/0xdc > [<ffffff80083fd840>] drm_helper_probe_single_connector_modes_merge_bits+0xe8/0x41c > [<ffffff80083fdb84>] drm_helper_probe_single_connector_modes+0x10/0x18 > [<ffffff8008418d24>] drm_mode_getconnector+0xf4/0x304 > [<ffffff800840cff0>] drm_ioctl+0x23c/0x390 > [<ffffff80081a8adc>] do_vfs_ioctl+0x4b8/0x58c > [<ffffff80081a8c10>] SyS_ioctl+0x60/0x88 > > Cc: Inki Dae <inki.dae@samsung.com> > Cc: Sean Paul <seanpaul@chromium.org> > Cc: Gustavo Padovan <gustavo.padovan@collabora.co.uk> > Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com> > > Signed-off-by: Mark Yao <mark.yao@rock-chips.com> Thanks for revising, this is much better. Reviewed-by: Sean Paul <seanpaul@chromium.org> > --- > Changes in v2: > - remove sub device power on/off callback, use pm_runtime_get/put is enough > to fix my problem, so will can avoid race to dpms. > > drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > index efac8ab..ff2d328 100644 > --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > @@ -1062,11 +1062,15 @@ int analogix_dp_get_modes(struct drm_connector *connector) > return 0; > } > > + pm_runtime_get_sync(dp->dev); > + > if (analogix_dp_handle_edid(dp) == 0) { > drm_mode_connector_update_edid_property(&dp->connector, edid); > num_modes += drm_add_edid_modes(&dp->connector, edid); > } > > + pm_runtime_put(dp->dev); > + > if (dp->plat_data->panel) > num_modes += drm_panel_get_modes(dp->plat_data->panel); > > @@ -1106,9 +1110,13 @@ analogix_dp_detect(struct drm_connector *connector, bool force) > return connector_status_disconnected; > } > > + pm_runtime_get_sync(dp->dev); > + > if (!analogix_dp_detect_hpd(dp)) > status = connector_status_connected; > > + pm_runtime_put(dp->dev); > + > ret = analogix_dp_prepare_panel(dp, false, false); > if (ret) > DRM_ERROR("Failed to unprepare panel (%d)\n", ret); > -- > 1.9.1 > >
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c index efac8ab..ff2d328 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c @@ -1062,11 +1062,15 @@ int analogix_dp_get_modes(struct drm_connector *connector) return 0; } + pm_runtime_get_sync(dp->dev); + if (analogix_dp_handle_edid(dp) == 0) { drm_mode_connector_update_edid_property(&dp->connector, edid); num_modes += drm_add_edid_modes(&dp->connector, edid); } + pm_runtime_put(dp->dev); + if (dp->plat_data->panel) num_modes += drm_panel_get_modes(dp->plat_data->panel); @@ -1106,9 +1110,13 @@ analogix_dp_detect(struct drm_connector *connector, bool force) return connector_status_disconnected; } + pm_runtime_get_sync(dp->dev); + if (!analogix_dp_detect_hpd(dp)) status = connector_status_connected; + pm_runtime_put(dp->dev); + ret = analogix_dp_prepare_panel(dp, false, false); if (ret) DRM_ERROR("Failed to unprepare panel (%d)\n", ret);
The drm callback ->detect and ->get_modes seems is not power safe, they may be called when device is power off, do register access on detect or get_modes will cause system die. Here is the path call ->detect before analogix_dp power on [<ffffff800843babc>] analogix_dp_detect+0x44/0xdc [<ffffff80083fd840>] drm_helper_probe_single_connector_modes_merge_bits+0xe8/0x41c [<ffffff80083fdb84>] drm_helper_probe_single_connector_modes+0x10/0x18 [<ffffff8008418d24>] drm_mode_getconnector+0xf4/0x304 [<ffffff800840cff0>] drm_ioctl+0x23c/0x390 [<ffffff80081a8adc>] do_vfs_ioctl+0x4b8/0x58c [<ffffff80081a8c10>] SyS_ioctl+0x60/0x88 Cc: Inki Dae <inki.dae@samsung.com> Cc: Sean Paul <seanpaul@chromium.org> Cc: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com> Signed-off-by: Mark Yao <mark.yao@rock-chips.com> --- Changes in v2: - remove sub device power on/off callback, use pm_runtime_get/put is enough to fix my problem, so will can avoid race to dpms. drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 8 ++++++++ 1 file changed, 8 insertions(+)