drm/tegra: dsi: Restore DPMS

In order to restore DPMS with atomic mode-setting, move all code from
the ->mode_set() callback into ->enable(). At the same time, rename the
->prepare() callback to ->disable() to use the names preferred by atomic
mode-setting. This simplifies the calling sequence and will allow DPMS
to use runtime PM in subsequent patches.

Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/dsi.c

@@ -119,6 +119,16 @@ static int tegra_dsi_show_regs(struct seq_file *s, void *data)
 {
 	struct drm_info_node *node = s->private;
 	struct tegra_dsi *dsi = node->info_ent->data;
+	struct drm_crtc *crtc = dsi->output.encoder.crtc;
+	struct drm_device *drm = node->minor->dev;
+	int err = 0;
+
+	drm_modeset_lock_all(drm);
+
+	if (!crtc || !crtc->state->active) {
+		err = -EBUSY;
+		goto unlock;
+	}
 
 #define DUMP_REG(name)						\
 	seq_printf(s, "%-32s %#05x %08x\n", #name, name,	\
@@ -208,7 +218,9 @@ static int tegra_dsi_show_regs(struct seq_file *s, void *data)
 
 #undef DUMP_REG
 
-	return 0;
+unlock:
+	drm_modeset_unlock_all(drm);
+	return err;
 }
 
 static struct drm_info_list debugfs_files[] = {
@@ -731,10 +743,6 @@ static void tegra_dsi_soft_reset(struct tegra_dsi *dsi)
 		tegra_dsi_soft_reset(dsi->slave);
 }
 
-static void tegra_dsi_connector_dpms(struct drm_connector *connector, int mode)
-{
-}
-
 static void tegra_dsi_connector_reset(struct drm_connector *connector)
 {
 	struct tegra_dsi_state *state;
@@ -761,7 +769,7 @@ tegra_dsi_connector_duplicate_state(struct drm_connector *connector)
 }
 
 static const struct drm_connector_funcs tegra_dsi_connector_funcs = {
-	.dpms = tegra_dsi_connector_dpms,
+	.dpms = drm_atomic_helper_connector_dpms,
 	.reset = tegra_dsi_connector_reset,
 	.detect = tegra_output_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
@@ -787,22 +795,48 @@ static const struct drm_encoder_funcs tegra_dsi_encoder_funcs = {
 	.destroy = tegra_output_encoder_destroy,
 };
 
-static void tegra_dsi_encoder_dpms(struct drm_encoder *encoder, int mode)
+static void tegra_dsi_encoder_disable(struct drm_encoder *encoder)
 {
-}
+	struct tegra_output *output = encoder_to_output(encoder);
+	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
+	struct tegra_dsi *dsi = to_dsi(output);
+	u32 value;
+	int err;
 
-static void tegra_dsi_encoder_prepare(struct drm_encoder *encoder)
-{
-}
+	if (output->panel)
+		drm_panel_disable(output->panel);
 
-static void tegra_dsi_encoder_commit(struct drm_encoder *encoder)
-{
+	tegra_dsi_video_disable(dsi);
+
+	/*
+	 * The following accesses registers of the display controller, so make
+	 * sure it's only executed when the output is attached to one.
+	 */
+	if (dc) {
+		value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
+		value &= ~DSI_ENABLE;
+		tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
+
+		tegra_dc_commit(dc);
+	}
+
+	err = tegra_dsi_wait_idle(dsi, 100);
+	if (err < 0)
+		dev_dbg(dsi->dev, "failed to idle DSI: %d\n", err);
+
+	tegra_dsi_soft_reset(dsi);
+
+	if (output->panel)
+		drm_panel_unprepare(output->panel);
+
+	tegra_dsi_disable(dsi);
+
+	return;
 }
 
-static void tegra_dsi_encoder_mode_set(struct drm_encoder *encoder,
-				       struct drm_display_mode *mode,
-				       struct drm_display_mode *adjusted)
+static void tegra_dsi_encoder_enable(struct drm_encoder *encoder)
 {
+	struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode;
 	struct tegra_output *output = encoder_to_output(encoder);
 	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
 	struct tegra_dsi *dsi = to_dsi(output);
@@ -840,45 +874,6 @@ static void tegra_dsi_encoder_mode_set(struct drm_encoder *encoder,
 	return;
 }
 
-static void tegra_dsi_encoder_disable(struct drm_encoder *encoder)
-{
-	struct tegra_output *output = encoder_to_output(encoder);
-	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
-	struct tegra_dsi *dsi = to_dsi(output);
-	u32 value;
-	int err;
-
-	if (output->panel)
-		drm_panel_disable(output->panel);
-
-	tegra_dsi_video_disable(dsi);
-
-	/*
-	 * The following accesses registers of the display controller, so make
-	 * sure it's only executed when the output is attached to one.
-	 */
-	if (dc) {
-		value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
-		value &= ~DSI_ENABLE;
-		tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
-
-		tegra_dc_commit(dc);
-	}
-
-	err = tegra_dsi_wait_idle(dsi, 100);
-	if (err < 0)
-		dev_dbg(dsi->dev, "failed to idle DSI: %d\n", err);
-
-	tegra_dsi_soft_reset(dsi);
-
-	if (output->panel)
-		drm_panel_unprepare(output->panel);
-
-	tegra_dsi_disable(dsi);
-
-	return;
-}
-
 static int
 tegra_dsi_encoder_atomic_check(struct drm_encoder *encoder,
 			       struct drm_crtc_state *crtc_state,
@@ -961,11 +956,8 @@ tegra_dsi_encoder_atomic_check(struct drm_encoder *encoder,
 }
 
 static const struct drm_encoder_helper_funcs tegra_dsi_encoder_helper_funcs = {
-	.dpms = tegra_dsi_encoder_dpms,
-	.prepare = tegra_dsi_encoder_prepare,
-	.commit = tegra_dsi_encoder_commit,
-	.mode_set = tegra_dsi_encoder_mode_set,
 	.disable = tegra_dsi_encoder_disable,
+	.enable = tegra_dsi_encoder_enable,
 	.atomic_check = tegra_dsi_encoder_atomic_check,
 };