drm: atmel-hlcdc: move output mode selection in CRTC implementation

In order to support multiple outputs we need to move the output mode
selection to the CRTC object, so that the output validity check can be
done against the drm_atomic_state.

If the connectors selected by a specific mode setting are requiring
incompatible bus format the atomic operation is aborted (->atomic_check()
returns -EINVAL).

In order to implement that, we need to define our own CRTC state and
overload default ->reset(), ->atomic_duplicate_state() and
->atomic_destroy_state() functions.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Nicolas Ferre <nicolas.ferre@atmel.com>

1 files changed, 136 insertions, 4 deletions

diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c
index 58c4f785cf84..021bd218655f 100644
--- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c
+++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c
@@ -32,6 +32,23 @@
 #include "atmel_hlcdc_dc.h"
 
 /**
+ * Atmel HLCDC CRTC state structure
+ *
+ * @base: base CRTC state
+ * @output_mode: RGBXXX output mode
+ */
+struct atmel_hlcdc_crtc_state {
+	struct drm_crtc_state base;
+	unsigned int output_mode;
+};
+
+static inline struct atmel_hlcdc_crtc_state *
+drm_crtc_state_to_atmel_hlcdc_crtc_state(struct drm_crtc_state *state)
+{
+	return container_of(state, struct atmel_hlcdc_crtc_state, base);
+}
+
+/**
  * Atmel HLCDC CRTC structure
  *
  * @base: base DRM CRTC structure
@@ -59,6 +76,7 @@ static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c)
 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
 	struct regmap *regmap = crtc->dc->hlcdc->regmap;
 	struct drm_display_mode *adj = &c->state->adjusted_mode;
+	struct atmel_hlcdc_crtc_state *state;
 	unsigned long mode_rate;
 	struct videomode vm;
 	unsigned long prate;
@@ -112,12 +130,15 @@ static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c)
 	if (adj->flags & DRM_MODE_FLAG_NHSYNC)
 		cfg |= ATMEL_HLCDC_HSPOL;
 
+	state = drm_crtc_state_to_atmel_hlcdc_crtc_state(c->state);
+	cfg |= state->output_mode << 8;
+
 	regmap_update_bits(regmap, ATMEL_HLCDC_CFG(5),
 			   ATMEL_HLCDC_HSPOL | ATMEL_HLCDC_VSPOL |
 			   ATMEL_HLCDC_VSPDLYS | ATMEL_HLCDC_VSPDLYE |
 			   ATMEL_HLCDC_DISPPOL | ATMEL_HLCDC_DISPDLY |
 			   ATMEL_HLCDC_VSPSU | ATMEL_HLCDC_VSPHO |
-			   ATMEL_HLCDC_GUARDTIME_MASK,
+			   ATMEL_HLCDC_GUARDTIME_MASK | ATMEL_HLCDC_MODE_MASK,
 			   cfg);
 }
 
@@ -221,14 +242,78 @@ void atmel_hlcdc_crtc_resume(struct drm_crtc *c)
 	}
 }
 
+#define ATMEL_HLCDC_RGB444_OUTPUT	BIT(0)
+#define ATMEL_HLCDC_RGB565_OUTPUT	BIT(1)
+#define ATMEL_HLCDC_RGB666_OUTPUT	BIT(2)
+#define ATMEL_HLCDC_RGB888_OUTPUT	BIT(3)
+#define ATMEL_HLCDC_OUTPUT_MODE_MASK	GENMASK(3, 0)
+
+static int atmel_hlcdc_crtc_select_output_mode(struct drm_crtc_state *state)
+{
+	unsigned int output_fmts = ATMEL_HLCDC_OUTPUT_MODE_MASK;
+	struct atmel_hlcdc_crtc_state *hstate;
+	struct drm_connector_state *cstate;
+	struct drm_connector *connector;
+	struct atmel_hlcdc_crtc *crtc;
+	int i;
+
+	crtc = drm_crtc_to_atmel_hlcdc_crtc(state->crtc);
+
+	for_each_connector_in_state(state->state, connector, cstate, i) {
+		struct drm_display_info *info = &connector->display_info;
+		unsigned int supported_fmts = 0;
+		int j;
+
+		if (!cstate->crtc)
+			continue;
+
+		for (j = 0; j < info->num_bus_formats; j++) {
+			switch (info->bus_formats[j]) {
+			case MEDIA_BUS_FMT_RGB444_1X12:
+				supported_fmts |= ATMEL_HLCDC_RGB444_OUTPUT;
+				break;
+			case MEDIA_BUS_FMT_RGB565_1X16:
+				supported_fmts |= ATMEL_HLCDC_RGB565_OUTPUT;
+				break;
+			case MEDIA_BUS_FMT_RGB666_1X18:
+				supported_fmts |= ATMEL_HLCDC_RGB666_OUTPUT;
+				break;
+			case MEDIA_BUS_FMT_RGB888_1X24:
+				supported_fmts |= ATMEL_HLCDC_RGB888_OUTPUT;
+				break;
+			default:
+				break;
+			}
+		}
+
+		if (crtc->dc->desc->conflicting_output_formats)
+			output_fmts &= supported_fmts;
+		else
+			output_fmts |= supported_fmts;
+	}
+
+	if (!output_fmts)
+		return -EINVAL;
+
+	hstate = drm_crtc_state_to_atmel_hlcdc_crtc_state(state);
+	hstate->output_mode = fls(output_fmts) - 1;
+
+	return 0;
+}
+
 static int atmel_hlcdc_crtc_atomic_check(struct drm_crtc *c,
 					 struct drm_crtc_state *s)
 {
 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
+	int ret;
 
 	if (atmel_hlcdc_dc_mode_valid(crtc->dc, &s->adjusted_mode) != MODE_OK)
 		return -EINVAL;
 
+	ret = atmel_hlcdc_crtc_select_output_mode(s);
+	if (ret)
+		return ret;
+
 	return atmel_hlcdc_plane_prepare_disc_area(s);
 }
 
@@ -292,13 +377,60 @@ void atmel_hlcdc_crtc_irq(struct drm_crtc *c)
 	atmel_hlcdc_crtc_finish_page_flip(drm_crtc_to_atmel_hlcdc_crtc(c));
 }
 
+void atmel_hlcdc_crtc_reset(struct drm_crtc *crtc)
+{
+	struct atmel_hlcdc_crtc_state *state;
+
+	if (crtc->state && crtc->state->mode_blob)
+		drm_property_unreference_blob(crtc->state->mode_blob);
+
+	if (crtc->state) {
+		state = drm_crtc_state_to_atmel_hlcdc_crtc_state(crtc->state);
+		kfree(state);
+	}
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (state) {
+		crtc->state = &state->base;
+		crtc->state->crtc = crtc;
+	}
+}
+
+static struct drm_crtc_state *
+atmel_hlcdc_crtc_duplicate_state(struct drm_crtc *crtc)
+{
+	struct atmel_hlcdc_crtc_state *state, *cur;
+
+	if (WARN_ON(!crtc->state))
+		return NULL;
+
+	state = kmalloc(sizeof(*state), GFP_KERNEL);
+	if (state)
+		__drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);
+
+	cur = drm_crtc_state_to_atmel_hlcdc_crtc_state(crtc->state);
+	state->output_mode = cur->output_mode;
+
+	return &state->base;
+}
+
+static void atmel_hlcdc_crtc_destroy_state(struct drm_crtc *crtc,
+					   struct drm_crtc_state *s)
+{
+	struct atmel_hlcdc_crtc_state *state;
+
+	state = drm_crtc_state_to_atmel_hlcdc_crtc_state(s);
+	__drm_atomic_helper_crtc_destroy_state(crtc, s);
+	kfree(state);
+}
+
 static const struct drm_crtc_funcs atmel_hlcdc_crtc_funcs = {
 	.page_flip = drm_atomic_helper_page_flip,
 	.set_config = drm_atomic_helper_set_config,
 	.destroy = atmel_hlcdc_crtc_destroy,
-	.reset = drm_atomic_helper_crtc_reset,
-	.atomic_duplicate_state =  drm_atomic_helper_crtc_duplicate_state,
-	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+	.reset = atmel_hlcdc_crtc_reset,
+	.atomic_duplicate_state =  atmel_hlcdc_crtc_duplicate_state,
+	.atomic_destroy_state = atmel_hlcdc_crtc_destroy_state,
 };
 
 int atmel_hlcdc_crtc_create(struct drm_device *dev)