The pre-retina MacBook Pro uses an LVDS panel and a gmux controller to switch the panel between its two GPUs. The panel mode in VBIOS is notoriously bogus on these machines.
Use drm_get_edid_switcheroo() in lieu of drm_get_edid() on LVDS if the vga_switcheroo handler is capable of temporarily switching the panel's DDC lines to the discrete GPU. This allows us to retrieve the EDID if the panel is currently muxed to the integrated GPU. Likewise, ask vga_switcheroo to switch DDC before probing LVDS connectors.
This only enables EDID probing on the pre-retina MBP (2008 - 2013). The retina MBP (2012 - present) uses eDP and gmux is not capable of switching AUX separately from the main link on these models. This will be addressed in later patches.
List of pre-retina MBPs with dual GPUs, either or both Nvidia: [MBP 5,1 2008 nvidia MCP79 + G96 pre-retina 15"] [MBP 5,2 2009 nvidia MCP79 + G96 pre-retina 17"] [MBP 5,3 2009 nvidia MCP79 + G96 pre-retina 15"] [MBP 6,2 2010 intel ILK + nvidia GT216 pre-retina 15"] [MBP 6,1 2010 intel ILK + nvidia GT216 pre-retina 17"] [MBP 9,1 2012 intel IVB + nvidia GK107 pre-retina 15"]
v3: Commit newly added due to introduction of drm_get_edid_switcheroo() wrapper which drivers need to opt-in to.
v5: Rebase on "vga_switcheroo: Add handler flags infrastructure", i.e. call drm_get_edid_switcheroo() only if the handler indicates that DDC is switchable.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115 Tested-by: Lukas Wunner lukas@wunner.de [MBP 9,1 2012 intel IVB + nvidia GK107 pre-retina 15"] Signed-off-by: Lukas Wunner lukas@wunner.de --- drivers/gpu/drm/nouveau/nouveau_connector.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c index fcebfae..ae96ebc 100644 --- a/drivers/gpu/drm/nouveau/nouveau_connector.c +++ b/drivers/gpu/drm/nouveau/nouveau_connector.c @@ -27,6 +27,7 @@ #include <acpi/button.h>
#include <linux/pm_runtime.h> +#include <linux/vga_switcheroo.h>
#include <drm/drmP.h> #include <drm/drm_edid.h> @@ -153,6 +154,17 @@ nouveau_connector_ddc_detect(struct drm_connector *connector) if (ret == 0) break; } else + if ((vga_switcheroo_handler_flags() & + VGA_SWITCHEROO_CAN_SWITCH_DDC) && + nv_encoder->dcb->type == DCB_OUTPUT_LVDS && + nv_encoder->i2c) { + int ret; + vga_switcheroo_lock_ddc(dev->pdev); + ret = nvkm_probe_i2c(nv_encoder->i2c, 0x50); + vga_switcheroo_unlock_ddc(dev->pdev); + if (ret) + break; + } else if (nv_encoder->i2c) { if (nvkm_probe_i2c(nv_encoder->i2c, 0x50)) break; @@ -265,7 +277,14 @@ nouveau_connector_detect(struct drm_connector *connector, bool force)
nv_encoder = nouveau_connector_ddc_detect(connector); if (nv_encoder && (i2c = nv_encoder->i2c) != NULL) { - nv_connector->edid = drm_get_edid(connector, i2c); + if ((vga_switcheroo_handler_flags() & + VGA_SWITCHEROO_CAN_SWITCH_DDC) && + nv_connector->type == DCB_CONNECTOR_LVDS) + nv_connector->edid = drm_get_edid_switcheroo(connector, + i2c); + else + nv_connector->edid = drm_get_edid(connector, i2c); + drm_mode_connector_update_edid_property(connector, nv_connector->edid); if (!nv_connector->edid) {