Hi,
I have a Thinkpad T440s (Haswell) connected to two additional Monitors via a Docking Station (MST).
During Bootup all three displays work, even when X is started. However, if the laptop display is turned off once (either because of power saving, or via xrandr), it fails to "come back". That is if I try to re-enable it the Display stays blank. I believe this used to work in 3.17.
Here is the xrandr Ouput of the edp, when its enabled (but staying blank): Screen 0: minimum 8 x 8, current 3840 x 1200, maximum 32767 x 32767 eDP1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 309mm x 175mm 1920x1080 60.0*+ 59.9
here is the debug output, while trying to enable it:
[ 416.314290] [drm:drm_mode_setcrtc] [CONNECTOR:19:eDP-1] [ 416.314294] [drm:intel_crtc_set_config] [CRTC:12] [FB:149] #connectors=1 (x y) (0 0) [ 416.314299] [drm:intel_set_config_compute_mode_changes] inactive crtc, full mode set [ 416.314303] [drm:intel_set_config_compute_mode_changes] computed changes for [CRTC:12], mode_changed=1, fb_changed=1 [ 416.314305] [drm:intel_modeset_stage_output_state] encoder changed, full mode switch [ 416.314309] [drm:intel_modeset_stage_output_state] [CONNECTOR:19:eDP-1] to [CRTC:12] [ 416.314312] [drm:intel_modeset_stage_output_state] [CONNECTOR:39:DP-3] to [CRTC:8] [ 416.314315] [drm:intel_modeset_stage_output_state] [CONNECTOR:43:DP-4] to [CRTC:16] [ 416.314317] [drm:intel_modeset_stage_output_state] crtc changed, full mode switch [ 416.314321] [drm:intel_modeset_stage_output_state] crtc enabled, full mode switch [ 416.314325] [drm:intel_modeset_affected_pipes] set mode pipe masks: modeset: 2, prepare: 2, disable: 0 [ 416.314329] [drm:connected_sink_compute_bpp] [CONNECTOR:19:eDP-1] checking for sink bpp constrains [ 416.314332] [drm:connected_sink_compute_bpp] clamping display bpp (was 24) to EDID reported max of 18 [ 416.314337] [drm:intel_dp_compute_config] DP link computation with max lane count 2 max bw 0a pixel clock 140100KHz [ 416.314341] [drm:intel_dp_compute_config] DP link bw 0a lane count 2 clock 270000 bpp 18 [ 416.314343] [drm:intel_dp_compute_config] DP link bw required 252180 available 432000 [ 416.314347] [drm:intel_modeset_pipe_config] plane bpp: 24, pipe bpp: 18, dithering: 1 [ 416.314351] [drm:intel_dump_pipe_config] [CRTC:12][modeset] config for pipe B [ 416.314353] [drm:intel_dump_pipe_config] cpu_transcoder: D [ 416.314355] [drm:intel_dump_pipe_config] pipe bpp: 18, dithering: 1 [ 416.314359] [drm:intel_dump_pipe_config] fdi/pch: 0, lanes: 0, gmch_m: 0, gmch_n: 0, link_m: 0, link_n: 0, tu: 0 [ 416.314363] [drm:intel_dump_pipe_config] dp: 1, gmch_m: 4896849, gmch_n: 8388608, link_m: 272047, link_n: 524288, tu: 64 [ 416.314392] [drm:intel_dump_pipe_config] dp: 1, gmch_m2: 0, gmch_n2: 0, link_m2: 0, link_n2: 0, tu2: 0 [ 416.314406] [drm:intel_dump_pipe_config] requested mode: [ 416.314422] [drm:drm_mode_debug_printmodeline] Modeline 0:"" 0 140100 1920 1980 2016 2092 1080 1083 1088 1116 0x0 0x9 [ 416.314435] [drm:intel_dump_pipe_config] adjusted mode: [ 416.314453] [drm:drm_mode_debug_printmodeline] Modeline 0:"1920x1080" 60 140100 1920 1980 2016 2092 1080 1083 1088 1116 0x48 0x9 [ 416.314468] [drm:intel_dump_crtc_timings] crtc timings: 140100 1920 1980 2016 2092 1080 1083 1088 1116, type: 0x48 flags: 0x9 [ 416.314482] [drm:intel_dump_pipe_config] port clock: 270000 [ 416.314496] [drm:intel_dump_pipe_config] pipe src size: 1920x1080 [ 416.314510] [drm:intel_dump_pipe_config] gmch pfit: control: 0x00000000, ratios: 0x00000000, lvds border: 0x00000000 [ 416.314521] [drm:intel_dump_pipe_config] pch pfit: pos: 0x00000000, size: 0x00000000, disabled [ 416.314524] [drm:intel_dump_pipe_config] ips: 0 [ 416.314527] [drm:intel_dump_pipe_config] double wide: 0 [ 416.314568] [drm:intel_edp_panel_on] Turn eDP power on [ 416.314575] [drm:wait_panel_power_cycle] Wait for panel power cycle [ 416.314585] [drm:wait_panel_status] mask b800000f value 00000000 status 00000000 control abcd0008 [ 416.314591] [drm:wait_panel_status] Wait complete [ 416.314599] [drm:wait_panel_on] Wait for panel power on [ 416.314606] [drm:wait_panel_status] mask b000000f value 80000008 status 0000000a control abcd000b [ 416.522545] [drm:wait_panel_status] Wait complete [ 416.523689] [drm:intel_dp_set_signal_levels] Using signal levels 00000000 [ 416.524311] [drm:intel_dp_start_link_train] clock recovery OK [ 416.525224] [drm:intel_dp_complete_link_train] Channel EQ done. DP Training successful [ 416.525528] [drm:intel_edp_backlight_on] [ 416.525533] [drm:intel_panel_enable_backlight] pipe B [ 416.525541] [drm:intel_panel_actually_set_backlight] set backlight PWM = 10 [ 416.530518] [drm:intel_edp_psr_match_conditions] PSR disable by flag [ 416.538553] [drm:ironlake_update_primary_plane] Writing base 030B0000 00000000 0 0 15360 [ 416.538575] [drm:intel_connector_check_state] [CONNECTOR:19:eDP-1] [ 416.538584] [drm:intel_connector_check_state] [CONNECTOR:39:DP-3] [ 416.538587] [drm:intel_connector_check_state] [CONNECTOR:43:DP-4] [ 416.538590] [drm:check_encoder_state] [ENCODER:18:TMDS-18] [ 416.538594] [drm:check_encoder_state] [ENCODER:26:TMDS-26] [ 416.538597] [drm:check_encoder_state] [ENCODER:28:DP MST-28] [ 416.538599] [drm:check_encoder_state] [ENCODER:29:DP MST-29] [ 416.538602] [drm:check_encoder_state] [ENCODER:30:DP MST-30] [ 416.538604] [drm:check_encoder_state] [ENCODER:33:TMDS-33] [ 416.538607] [drm:check_encoder_state] [ENCODER:35:DP MST-35] [ 416.538610] [drm:check_encoder_state] [ENCODER:36:DP MST-36] [ 416.538612] [drm:check_encoder_state] [ENCODER:37:DP MST-37] [ 416.538615] [drm:check_crtc_state] [CRTC:8] [ 416.538626] [drm:check_crtc_state] [CRTC:12] [ 416.538636] [drm:check_crtc_state] [CRTC:16] [ 416.538646] [drm:check_shared_dpll_state] WRPLL 1 [ 416.538649] [drm:check_shared_dpll_state] WRPLL 2 [ 416.538699] [drm:intel_backlight_device_update_status] updating intel_backlight, brightness=851/851 [ 416.538702] [drm:intel_panel_actually_set_backlight] set backlight PWM = 851 [ 416.538835] [drm:intel_backlight_device_update_status] updating intel_backlight, brightness=851/851 [ 416.538840] [drm:intel_panel_actually_set_backlight] set backlight PWM = 851 [ 416.538848] [drm:intel_edp_backlight_power] panel power control backlight disable [ 416.742563] [drm:add_framebuffer_internal] [FB:156] [ 419.195100] [drm:edp_panel_vdd_off_sync] Turning eDP VDD off [ 419.195112] [drm:edp_panel_vdd_off_sync] PP_STATUS: 0x80000008 PP_CONTROL: 0xabcd0003
I'm happy to provide further input.
Best Regards Arnd
On Thu, 06 Nov 2014, Arnd Hannemann arnd@arndnet.de wrote:
Hi,
I have a Thinkpad T440s (Haswell) connected to two additional Monitors via a Docking Station (MST).
During Bootup all three displays work, even when X is started. However, if the laptop display is turned off once (either because of power saving, or via xrandr), it fails to "come back". That is if I try to re-enable it the Display stays blank. I believe this used to work in 3.17.
Here is the xrandr Ouput of the edp, when its enabled (but staying blank): Screen 0: minimum 8 x 8, current 3840 x 1200, maximum 32767 x 32767 eDP1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 309mm x 175mm 1920x1080 60.0*+ 59.9
here is the debug output, while trying to enable it:
...
[ 416.538848] [drm:intel_edp_backlight_power] panel power control backlight disable
I'm happy to provide further input.
What does cat /sys/class/backlight/intel_backlight/bl_power say? What if you echo 0 there?
BR, Jani.
Hi,
thanks for your quick response.
Am 06.11.2014 um 10:39 schrieb Jani Nikula:
On Thu, 06 Nov 2014, Arnd Hannemann arnd@arndnet.de wrote:
Hi,
I have a Thinkpad T440s (Haswell) connected to two additional Monitors via a Docking Station (MST).
During Bootup all three displays work, even when X is started. However, if the laptop display is turned off once (either because of power saving, or via xrandr), it fails to "come back". That is if I try to re-enable it the Display stays blank. I believe this used to work in 3.17.
Here is the xrandr Ouput of the edp, when its enabled (but staying blank): Screen 0: minimum 8 x 8, current 3840 x 1200, maximum 32767 x 32767 eDP1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 309mm x 175mm 1920x1080 60.0*+ 59.9
here is the debug output, while trying to enable it:
...
[ 416.538848] [drm:intel_edp_backlight_power] panel power control backlight disable
I'm happy to provide further input.
What does cat /sys/class/backlight/intel_backlight/bl_power say? What if
root@kallisto:~# cat /sys/class/backlight/intel_backlight/bl_power 1
you echo 0 there?
:-) Works my display comes back, when I echo 0 there.
Is user-space doing something wrong here?
Best regards Arnd
On Thu, 06 Nov 2014, Arnd Hannemann arnd@arndnet.de wrote:
Hi,
thanks for your quick response.
Am 06.11.2014 um 10:39 schrieb Jani Nikula:
On Thu, 06 Nov 2014, Arnd Hannemann arnd@arndnet.de wrote:
Hi,
I have a Thinkpad T440s (Haswell) connected to two additional Monitors via a Docking Station (MST).
During Bootup all three displays work, even when X is started. However, if the laptop display is turned off once (either because of power saving, or via xrandr), it fails to "come back". That is if I try to re-enable it the Display stays blank. I believe this used to work in 3.17.
Here is the xrandr Ouput of the edp, when its enabled (but staying blank): Screen 0: minimum 8 x 8, current 3840 x 1200, maximum 32767 x 32767 eDP1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 309mm x 175mm 1920x1080 60.0*+ 59.9
here is the debug output, while trying to enable it:
...
[ 416.538848] [drm:intel_edp_backlight_power] panel power control backlight disable
I'm happy to provide further input.
What does cat /sys/class/backlight/intel_backlight/bl_power say? What if
root@kallisto:~# cat /sys/class/backlight/intel_backlight/bl_power 1
you echo 0 there?
:-) Works my display comes back, when I echo 0 there.
Is user-space doing something wrong here?
If the userspace wishes to switch off backlight, then it's doing nothing wrong at all! ;)
Here's the story as I know it.
Once upon a time someone added the bl_power attribute to the sysfs class backlight interface. Even though the name implies a boolean backlight power, the values are in fact FB_BLANK_* from fb.h, and power on is FB_BLANK_UNBLANK, or 0. All the other values are various levels of blanking which make little sense to backlight, and thus any non-zero values mean power off. [1]
Until recently, intel_backlight of drm/i915 did not support bl_power at all. We ignored the attribute altogether. However changing bl_power from its default 0 did cause a backlight update hook to be called. In some edge cases doing this fixed some backlight issues by reprogramming the backlight intensity, and probably lead to the false assumption that bl_power needed to be set to 1 to enable power.
Now that we've enabled support for bl_power attribute (on eDP at least), the previously harmless, or sometimes even helpful, bl_power=1 actually does what it means. That is, switch off the backlight.
Please try this patch (untested) to find out the culprit.
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c index bddc8b17a4d8..8cf5c6cdeef5 100644 --- a/drivers/video/backlight/backlight.c +++ b/drivers/video/backlight/backlight.c @@ -143,6 +143,7 @@ static ssize_t bl_power_store(struct device *dev, struct device_attribute *attr, rc = -ENXIO; mutex_lock(&bd->ops_lock); if (bd->ops) { + printk(KERN_INFO "bl_power %lu by %s\n", power, current->comm); pr_debug("set power to %lu\n", power); if (bd->props.power != power) { bd->props.power = power;
BR, Jani.
[1] http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Document... ("Read the documentation and you'll get it right" does not score well in Rusty's API design manifesto)
Hi,
Am 06.11.2014 um 13:53 schrieb Jani Nikula:
root@kallisto:~# cat /sys/class/backlight/intel_backlight/bl_power 1
you echo 0 there?
:-) Works my display comes back, when I echo 0 there.
Is user-space doing something wrong here?
If the userspace wishes to switch off backlight, then it's doing nothing wrong at all! ;)
Here's the story as I know it.
Once upon a time someone added the bl_power attribute to the sysfs class backlight interface. Even though the name implies a boolean backlight power, the values are in fact FB_BLANK_* from fb.h, and power on is FB_BLANK_UNBLANK, or 0. All the other values are various levels of blanking which make little sense to backlight, and thus any non-zero values mean power off. [1]
Until recently, intel_backlight of drm/i915 did not support bl_power at all. We ignored the attribute altogether. However changing bl_power from its default 0 did cause a backlight update hook to be called. In some edge cases doing this fixed some backlight issues by reprogramming the backlight intensity, and probably lead to the false assumption that bl_power needed to be set to 1 to enable power.
Now that we've enabled support for bl_power attribute (on eDP at least), the previously harmless, or sometimes even helpful, bl_power=1 actually does what it means. That is, switch off the backlight.
Thanks for your elaborated answer.
Please try this patch (untested) to find out the culprit.
Thanks, its the intel xorg driver: [ 255.777798] bl_power 1 by Xorg
I seems it was already corrected upstream, by Chris Wilson two days ago: http://cgit.freedesktop.org/xorg/driver/xf86-video-intel/commit/?id=7ecc7786...
Best regards Arnd
dri-devel@lists.freedesktop.org
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Arnd Hannemann -
Jani Nikula