drm/i915/dsi: Init panel-enable GPIO to low when the LCD is initially off (v2)

When the LCD has not been turned on by the firmware/GOP, because e.g. the
device was booted with an external monitor connected over HDMI, we should
not turn on the panel-enable GPIO when we request it.

Turning on the panel-enable GPIO when we request it, means we turn it on
too early in the init-sequence, which causes some panels to not correctly
light up.

This commits adds a panel_is_on parameter to intel_dsi_vbt_gpio_init()
and makes intel_dsi_vbt_gpio_init() set the initial GPIO value accordingly.

This fixes the panel not lighting up on a Thundersoft TST168 tablet when
booted with an external monitor connected over HDMI.

Changes in v2:
- Call intel_dsi_get_hw_state() to check if the panel is on instead of
  relying on the current_mode pointer

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191216205122.1850923-4-hdegoede@redhat.com

diff --git a/drivers/gpu/drm/i915/display/intel_dsi.h b/drivers/gpu/drm/i915/display/intel_dsi.h
index de7e51c..675771e 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dsi.h
+++ b/drivers/gpu/drm/i915/display/intel_dsi.h
@@ -203,7 +203,7 @@ void bxt_dsi_reset_clocks(struct intel_encoder *encoder, enum port port);
 
 /* intel_dsi_vbt.c */
 bool intel_dsi_vbt_init(struct intel_dsi *intel_dsi, u16 panel_id);
-void intel_dsi_vbt_gpio_init(struct intel_dsi *intel_dsi);
+void intel_dsi_vbt_gpio_init(struct intel_dsi *intel_dsi, bool panel_is_on);
 void intel_dsi_vbt_gpio_cleanup(struct intel_dsi *intel_dsi);
 void intel_dsi_vbt_exec_sequence(struct intel_dsi *intel_dsi,
                                 enum mipi_seq seq_id);

diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
index 8be7d6c..4210f44 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
+++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
@@ -688,17 +688,16 @@ bool intel_dsi_vbt_init(struct intel_dsi *intel_dsi, u16 panel_id)
  * On some BYT/CHT devs some sequences are incomplete and we need to manually
  * control some GPIOs.
  */
-void intel_dsi_vbt_gpio_init(struct intel_dsi *intel_dsi)
+void intel_dsi_vbt_gpio_init(struct intel_dsi *intel_dsi, bool panel_is_on)
 {
        struct drm_device *dev = intel_dsi->base.base.dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct mipi_config *mipi_config = dev_priv->vbt.dsi.config;
+       enum gpiod_flags flags = panel_is_on ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
 
        if ((IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) &&
            mipi_config->pwm_blc == PPS_BLC_PMIC) {
-               intel_dsi->gpio_panel =
-                       gpiod_get(dev->dev, "panel", GPIOD_OUT_HIGH);
-
+               intel_dsi->gpio_panel = gpiod_get(dev->dev, "panel", flags);
                if (IS_ERR(intel_dsi->gpio_panel)) {
                        DRM_ERROR("Failed to own gpio for panel control\n");
                        intel_dsi->gpio_panel = NULL;

diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c
index a20b7d8..bd368a0 100644 (file)
--- a/drivers/gpu/drm/i915/display/vlv_dsi.c
+++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
@@ -1815,6 +1815,7 @@ void vlv_dsi_init(struct drm_i915_private *dev_priv)
        struct drm_connector *connector;
        struct drm_display_mode *current_mode, *fixed_mode;
        enum port port;
+       enum pipe pipe;
 
        DRM_DEBUG_KMS("\n");
 
@@ -1913,7 +1914,8 @@ void vlv_dsi_init(struct drm_i915_private *dev_priv)
 
        vlv_dphy_param_init(intel_dsi);
 
-       intel_dsi_vbt_gpio_init(intel_dsi);
+       intel_dsi_vbt_gpio_init(intel_dsi,
+                               intel_dsi_get_hw_state(intel_encoder, &pipe));
 
        drm_connector_init(dev, connector, &intel_dsi_connector_funcs,
                           DRM_MODE_CONNECTOR_DSI);