[PATCH v2 05/10] drm/i915/dsi: Execute MIPI_SEQ_DEASSERT_RESET before calling device_ready()

[Hans de Goede]

Execute MIPI_SEQ_DEASSERT_RESET before putting the device in ready
state (LP-11), this is the sequence in which things should be done
according to the spec.

Signed-off-by: Hans de Goede <hdegoede at redhat.com>
Reviewed-by: Bob Paauwe <bob.j.paauwe at intel.com>
---
 drivers/gpu/drm/i915/intel_dsi.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index 04fd01d..b7b8c6d 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -637,10 +637,13 @@ static void intel_dsi_pre_enable(struct intel_encoder *encoder,
 	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_POWER_ON);
 	msleep(intel_dsi->panel_on_delay);
 
-	/* put device in ready state */
+	/* Deassert reset */
+	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);
+
+	/* Put device in ready state (LP-11) */
 	intel_dsi_device_ready(encoder);
 
-	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);
+	/* Send initialization commands in LP mode */
 	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_INIT_OTP);
 
 	/* Enable port in pre-enable phase itself because as per hw team
@@ -733,6 +736,7 @@ static void intel_dsi_post_disable(struct intel_encoder *encoder,
 	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_BACKLIGHT_OFF);
 	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_DISPLAY_OFF);
 
+	/* Transition to LP-00 */
 	intel_dsi_clear_device_ready(encoder);
 
 	if (IS_BROXTON(dev_priv)) {
@@ -756,6 +760,7 @@ static void intel_dsi_post_disable(struct intel_encoder *encoder,
 		I915_WRITE(DSPCLK_GATE_D, val);
 	}
 
+	/* Assert reset */
 	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_ASSERT_RESET);
 
 	/* Power off, try both CRC pmic gpio and VBT */
-- 
2.9.3