Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Aradhya Bhatia <a-bhatia1@ti.com>
To:     Tomi Valkeinen <tomba@kernel.org>, Jyri Sarha <jyri.sarha@iki.fi>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Andrzej Hajda <andrzej.hajda@intel.com>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Robert Foss <rfoss@kernel.org>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        Rahul T R <r-ravikumar@ti.com>,
        Swapnil Jakhade <sjakhade@cadence.com>,
        Boris Brezillon <boris.brezillon@collabora.com>,
        Francesco Dolcini <francesco@dolcini.it>
CC:     DRI Development List <dri-devel@lists.freedesktop.org>,
        Linux Kernel List <linux-kernel@vger.kernel.org>,
        Nishanth Menon <nm@ti.com>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Devarsh Thakkar <devarsht@ti.com>,
        Jayesh Choudhary <j-choudhary@ti.com>,
        Aradhya Bhatia <a-bhatia1@ti.com>
Subject: [PATCH v6 3/8] drm/bridge: mhdp8546: Add minimal format negotiation
Date:   Tue, 9 May 2023 15:00:31 +0530
Message-ID: <20230509093036.3303-4-a-bhatia1@ti.com>
In-Reply-To: <20230509093036.3303-1-a-bhatia1@ti.com>
References: <20230509093036.3303-1-a-bhatia1@ti.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
Precedence: bulk

From: Nikhil Devshatwar <nikhil.nd@ti.com>

With new connector model, mhdp bridge will not create the connector and
SoC driver will rely on format negotiation to setup the encoder format.

Support minimal format negotiations hooks in the drm_bridge_funcs.
Complete format negotiation can be added based on EDID data.
This patch adds the minimal required support to avoid failure
after moving to new connector model.

Signed-off-by: Nikhil Devshatwar <nikhil.nd@ti.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
---

Notes:

    changes from v1:
    * cosmetic fixes, commit message update.

    changes from v5:
    * dropped the default_bus_format variable and directly assigned
      MEDIA_BUS_FMT_RGB121212_1X36 to input_fmts.

 .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 25 +++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
index f6822dfa3805..623e4235c94f 100644
--- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
@@ -2146,6 +2146,30 @@ cdns_mhdp_bridge_atomic_reset(struct drm_bridge *bridge)
 	return &cdns_mhdp_state->base;
 }
 
+static u32 *cdns_mhdp_get_input_bus_fmts(struct drm_bridge *bridge,
+					 struct drm_bridge_state *bridge_state,
+					 struct drm_crtc_state *crtc_state,
+					 struct drm_connector_state *conn_state,
+					 u32 output_fmt,
+					 unsigned int *num_input_fmts)
+{
+	u32 *input_fmts;
+
+	*num_input_fmts = 0;
+
+	if (output_fmt != MEDIA_BUS_FMT_FIXED)
+		return NULL;
+
+	input_fmts = kzalloc(sizeof(*input_fmts), GFP_KERNEL);
+	if (!input_fmts)
+		return NULL;
+
+	*num_input_fmts = 1;
+	input_fmts[0] = MEDIA_BUS_FMT_RGB121212_1X36;
+
+	return input_fmts;
+}
+
 static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
 				  struct drm_bridge_state *bridge_state,
 				  struct drm_crtc_state *crtc_state,
@@ -2210,6 +2234,7 @@ static const struct drm_bridge_funcs cdns_mhdp_bridge_funcs = {
 	.atomic_duplicate_state = cdns_mhdp_bridge_atomic_duplicate_state,
 	.atomic_destroy_state = cdns_mhdp_bridge_atomic_destroy_state,
 	.atomic_reset = cdns_mhdp_bridge_atomic_reset,
+	.atomic_get_input_bus_fmts = cdns_mhdp_get_input_bus_fmts,
 	.detect = cdns_mhdp_bridge_detect,
 	.get_edid = cdns_mhdp_bridge_get_edid,
 	.hpd_enable = cdns_mhdp_bridge_hpd_enable,
-- 
2.40.1