From 1a1841d300a1b6cac35b0761755364d6d3e10b2e Mon Sep 17 00:00:00 2001
From: Ben Skeggs <bskeggs@redhat.com>
Date: Mon, 10 Dec 2012 18:53:43 +1000
Subject: [PATCH] drm/nouveau: do not forcibly power on lvds panels
This fix was put in place to fix a bug where the eDP panel on certain
laptops fails to respond over the aux channel after suspend.
It appears that on some systems (Dell M6600, with LVDS panel) there's a
very bad interaction with the eDP init table that causes the SOR to get
very confused and not drive the panel correctly, leading to bleed.
A DPMS off/on cycle is enough to bring it back, but, this will avoid the
problem by not touching the panel GPIOs at times we're not meant to.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
---
drivers/gpu/drm/nouveau/nouveau_connector.c | 30 ++++++++++++++++++---
drivers/gpu/drm/nouveau/nouveau_display.c | 9 -------
2 files changed, 26 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index ac340ba320174..e620ba8271b4b 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -127,12 +127,26 @@ nouveau_connector_ddc_detect(struct drm_connector *connector,
struct nouveau_encoder **pnv_encoder)
{
struct drm_device *dev = connector->dev;
+ struct nouveau_connector *nv_connector = nouveau_connector(connector);
struct nouveau_drm *drm = nouveau_drm(dev);
+ struct nouveau_gpio *gpio = nouveau_gpio(drm->device);
struct nouveau_i2c *i2c = nouveau_i2c(drm->device);
- int i;
+ struct nouveau_i2c_port *port = NULL;
+ int i, panel = -ENODEV;
+
+ /* eDP panels need powering on by us (if the VBIOS doesn't default it
+ * to on) before doing any AUX channel transactions. LVDS panel power
+ * is handled by the SOR itself, and not required for LVDS DDC.
+ */
+ if (nv_connector->type == DCB_CONNECTOR_eDP) {
+ panel = gpio->get(gpio, 0, DCB_GPIO_PANEL_POWER, 0xff);
+ if (panel == 0) {
+ gpio->set(gpio, 0, DCB_GPIO_PANEL_POWER, 0xff, 1);
+ msleep(300);
+ }
+ }
for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
- struct nouveau_i2c_port *port = NULL;
struct nouveau_encoder *nv_encoder;
struct drm_mode_object *obj;
int id;
@@ -150,11 +164,19 @@ nouveau_connector_ddc_detect(struct drm_connector *connector,
port = i2c->find(i2c, nv_encoder->dcb->i2c_index);
if (port && nv_probe_i2c(port, 0x50)) {
*pnv_encoder = nv_encoder;
- return port;
+ break;
}
+
+ port = NULL;
}
- return NULL;
+ /* eDP panel not detected, restore panel power GPIO to previous
+ * state to avoid confusing the SOR for other output types.
+ */
+ if (!port && panel == 0)
+ gpio->set(gpio, 0, DCB_GPIO_PANEL_POWER, 0xff, panel);
+
+ return port;
}
static struct nouveau_encoder *
diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c
index e4188f24fc758..508b00a2ce0de 100644
--- a/drivers/gpu/drm/nouveau/nouveau_display.c
+++ b/drivers/gpu/drm/nouveau/nouveau_display.c
@@ -225,15 +225,6 @@ nouveau_display_init(struct drm_device *dev)
if (ret)
return ret;
- /* power on internal panel if it's not already. the init tables of
- * some vbios default this to off for some reason, causing the
- * panel to not work after resume
- */
- if (gpio && gpio->get(gpio, 0, DCB_GPIO_PANEL_POWER, 0xff) == 0) {
- gpio->set(gpio, 0, DCB_GPIO_PANEL_POWER, 0xff, 1);
- msleep(300);
- }
-
/* enable polling for external displays */
drm_kms_helper_poll_enable(dev);
--
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