drm/i915/dsi: Use unconditional msleep() instead of intel_dsi_msleep()

The intel_dsi_msleep() helper skips sleeping if the MIPI-sequences have
a version of 3 or newer and the panel is in vid-mode.

This is based on the big comment around line 730 which starts with
"Panel enable/disable sequences from the VBT spec.", where
the "v3 video mode seq" column does not have any wait t# entries.

Checking the Windows driver shows that it does always honor
the VBT delays independent of the version of the VBT sequences.

Commit 6fdb335f ("drm/i915/dsi: Use unconditional msleep for
the panel_on_delay when there is no reset-deassert MIPI-sequence")
switched to a direct msleep() instead of intel_dsi_msleep()
when there is no MIPI_SEQ_DEASSERT_RESET sequence, to fix
the panel on an Acer Aspire Switch 10 E SW3-016 not turning on.

And now testing on a Nextbook Ares 8A shows that panel_on_delay
must always be honored otherwise the panel will not turn on.

Instead of only always using regular msleep() for panel_on_delay
do as Windows does and always use regular msleep() everywhere
were intel_dsi_msleep() is used and drop the intel_dsi_msleep()
helper.

Changes in v2:
- Replace all intel_dsi_msleep() calls instead of just
  the intel_dsi_msleep(panel_on_delay) call

Cc: stable@vger.kernel.org
Fixes: 6fdb335f ("drm/i915/dsi: Use unconditional msleep for the panel_on_delay when there is no reset-deassert MIPI-sequence")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230425194441.68086-1-hdegoede@redhat.com
(cherry picked from commit fa83c121)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

drivers/gpu/drm/i915/display/icl_dsi.c

@@ -1140,7 +1140,7 @@ static void gen11_dsi_powerup_panel(struct intel_encoder *encoder)
 
 	/* panel power on related mipi dsi vbt sequences */
 	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_POWER_ON);
-	intel_dsi_msleep(intel_dsi, intel_dsi->panel_on_delay);
+	msleep(intel_dsi->panel_on_delay);
 	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);
 	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_INIT_OTP);
 	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DISPLAY_ON);

drivers/gpu/drm/i915/display/intel_dsi_vbt.c

@@ -763,17 +763,6 @@ void intel_dsi_vbt_exec_sequence(struct intel_dsi *intel_dsi,
 		gpiod_set_value_cansleep(intel_dsi->gpio_backlight, 0);
 }
 
-void intel_dsi_msleep(struct intel_dsi *intel_dsi, int msec)
-{
-	struct intel_connector *connector = intel_dsi->attached_connector;
-
-	/* For v3 VBTs in vid-mode the delays are part of the VBT sequences */
-	if (is_vid_mode(intel_dsi) && connector->panel.vbt.dsi.seq_version >= 3)
-		return;
-
-	msleep(msec);
-}
-
 void intel_dsi_log_params(struct intel_dsi *intel_dsi)
 {
 	struct drm_i915_private *i915 = to_i915(intel_dsi->base.base.dev);

drivers/gpu/drm/i915/display/intel_dsi_vbt.h

@@ -16,7 +16,6 @@ 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);
-void intel_dsi_msleep(struct intel_dsi *intel_dsi, int msec);
 void intel_dsi_log_params(struct intel_dsi *intel_dsi);
 
 #endif /* __INTEL_DSI_VBT_H__ */

drivers/gpu/drm/i915/display/vlv_dsi.c

@@ -737,7 +737,6 @@ static void intel_dsi_pre_enable(struct intel_atomic_state *state,
 {
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
 	struct intel_crtc *crtc = to_intel_crtc(pipe_config->uapi.crtc);
-	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 	enum pipe pipe = crtc->pipe;
 	enum port port;
@@ -779,21 +778,10 @@ static void intel_dsi_pre_enable(struct intel_atomic_state *state,
 	if (!IS_GEMINILAKE(dev_priv))
 		intel_dsi_prepare(encoder, pipe_config);
 
+	/* Give the panel time to power-on and then deassert its reset */
 	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_POWER_ON);
-
-	/*
-	 * Give the panel time to power-on and then deassert its reset.
-	 * Depending on the VBT MIPI sequences version the deassert-seq
-	 * may contain the necessary delay, intel_dsi_msleep() will skip
-	 * the delay in that case. If there is no deassert-seq, then an
-	 * unconditional msleep is used to give the panel time to power-on.
-	 */
-	if (connector->panel.vbt.dsi.sequence[MIPI_SEQ_DEASSERT_RESET]) {
-		intel_dsi_msleep(intel_dsi, intel_dsi->panel_on_delay);
-		intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);
-	} else {
 	msleep(intel_dsi->panel_on_delay);
-	}
+	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);
 
 	if (IS_GEMINILAKE(dev_priv)) {
 		glk_cold_boot = glk_dsi_enable_io(encoder);
@@ -827,7 +815,7 @@ static void intel_dsi_pre_enable(struct intel_atomic_state *state,
 		msleep(20); /* XXX */
 		for_each_dsi_port(port, intel_dsi->ports)
 			dpi_send_cmd(intel_dsi, TURN_ON, false, port);
-		intel_dsi_msleep(intel_dsi, 100);
+		msleep(100);
 
 		intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DISPLAY_ON);
 
@@ -949,7 +937,7 @@ static void intel_dsi_post_disable(struct intel_atomic_state *state,
 	/* Assert reset */
 	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_ASSERT_RESET);
 
-	intel_dsi_msleep(intel_dsi, intel_dsi->panel_off_delay);
+	msleep(intel_dsi->panel_off_delay);
 	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_POWER_OFF);
 
 	intel_dsi->panel_power_off_time = ktime_get_boottime();