drm/rockchip: Add support for Rockchip Soc RGB output interface

Some Rockchip CRTCs, like rv1108 and px30, can directly output parallel
and serial RGB data to panel or conversion chip.

So add a feature-bit for vops to mark the ability for these direct
outputs and add an internal encoder in that case, that can attach to
bridge chipsor panels.

Changes in v7:
    1. forget to delete rockchip_rgb_driver and delete it.
Changes in v6:
    1. Update according to Heiko Stuebner' implemention, rgb output is
       part of vop's feature, should not register as a independent
       driver.
Changes in v5:
    1. add SPDX-License-Identifier tag
Changes in v4:
    1. add support px30;
Changes in v3:
    1. update for rgb-mode move to panel node.
Changes in v2:
    1. add error log when probe failed;
    2. update name_to_output_mode() according to sean's suggest;
    3. Fix uninitialized use of ret.

Signed-off-by: Sandy Huang <hjc@rock-chips.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20180830211207.10480-3-heiko@sntech.de

6 files changed, 222 insertions, 0 deletions

diff --git a/drivers/gpu/drm/rockchip/Kconfig b/drivers/gpu/drm/rockchip/Kconfig
index 0534dc1ca32a..26438d45732b 100644
--- a/drivers/gpu/drm/rockchip/Kconfig
+++ b/drivers/gpu/drm/rockchip/Kconfig
@@ -8,6 +8,7 @@ config DRM_ROCKCHIP
         select DRM_ANALOGIX_DP if ROCKCHIP_ANALOGIX_DP
         select DRM_DW_HDMI if ROCKCHIP_DW_HDMI
         select DRM_MIPI_DSI if ROCKCHIP_DW_MIPI_DSI
+        select DRM_RGB if ROCKCHIP_RGB
         select SND_SOC_HDMI_CODEC if ROCKCHIP_CDN_DP && SND_SOC
         help
           Choose this option if you have a Rockchip soc chipset.
@@ -66,4 +67,14 @@ config ROCKCHIP_LVDS
           Rockchip rk3288 SoC has LVDS TX Controller can be used, and it
           support LVDS, rgb, dual LVDS output mode. say Y to enable its
           driver.
+
+config ROCKCHIP_RGB
+        bool "Rockchip RGB support"
+        depends on DRM_ROCKCHIP
+        depends on PINCTRL
+        help
+          Choose this option to enable support for Rockchip RGB output.
+          Some Rockchip CRTCs, like rv1108, can directly output parallel
+          and serial RGB format to panel or connect to a conversion chip.
+          say Y to enable its driver.
 endif
diff --git a/drivers/gpu/drm/rockchip/Makefile b/drivers/gpu/drm/rockchip/Makefile
index a314e2109e76..868263ff0302 100644
--- a/drivers/gpu/drm/rockchip/Makefile
+++ b/drivers/gpu/drm/rockchip/Makefile
@@ -14,5 +14,6 @@ rockchipdrm-$(CONFIG_ROCKCHIP_DW_HDMI) += dw_hdmi-rockchip.o
 rockchipdrm-$(CONFIG_ROCKCHIP_DW_MIPI_DSI) += dw-mipi-dsi.o
 rockchipdrm-$(CONFIG_ROCKCHIP_INNO_HDMI) += inno_hdmi.o
 rockchipdrm-$(CONFIG_ROCKCHIP_LVDS) += rockchip_lvds.o
+rockchipdrm-$(CONFIG_ROCKCHIP_RGB) += rockchip_rgb.o
 
 obj-$(CONFIG_DRM_ROCKCHIP) += rockchipdrm.o
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index 17f9ed688841..0c35a88e33dd 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
@@ -42,6 +42,7 @@
 #include "rockchip_drm_fb.h"
 #include "rockchip_drm_psr.h"
 #include "rockchip_drm_vop.h"
+#include "rockchip_rgb.h"
 
 #define VOP_WIN_SET(x, win, name, v) \
                 vop_reg_set(vop, &win->phy->name, win->base, ~0, v, #name)
@@ -93,6 +94,7 @@ struct vop_win {
         struct vop *vop;
 };
 
+struct rockchip_rgb;
 struct vop {
         struct drm_crtc crtc;
         struct device *dev;
@@ -136,6 +138,9 @@ struct vop {
         /* vop dclk reset */
         struct reset_control *dclk_rst;
 
+        /* optional internal rgb encoder */
+        struct rockchip_rgb *rgb;
+
         struct vop_win win[];
 };
 
@@ -1638,6 +1643,14 @@ static int vop_bind(struct device *dev, struct device *master, void *data)
         if (ret)
                 goto err_disable_pm_runtime;
 
+        if (vop->data->feature & VOP_FEATURE_INTERNAL_RGB) {
+                vop->rgb = rockchip_rgb_init(dev, &vop->crtc, vop->drm_dev);
+                if (IS_ERR(vop->rgb)) {
+                        ret = PTR_ERR(vop->rgb);
+                        goto err_disable_pm_runtime;
+                }
+        }
+
         return 0;
 
 err_disable_pm_runtime:
@@ -1650,6 +1663,9 @@ static void vop_unbind(struct device *dev, struct device *master, void *data)
 {
         struct vop *vop = dev_get_drvdata(dev);
 
+        if (vop->rgb)
+                rockchip_rgb_fini(vop->rgb);
+
         pm_runtime_disable(dev);
         vop_destroy_crtc(vop);
 
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
index fcb91041a666..fd5765dfd637 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
@@ -162,6 +162,7 @@ struct vop_data {
         unsigned int win_size;
 
 #define VOP_FEATURE_OUTPUT_RGB10        BIT(0)
+#define VOP_FEATURE_INTERNAL_RGB        BIT(1)
         u64 feature;
 };
 
diff --git a/drivers/gpu/drm/rockchip/rockchip_rgb.c b/drivers/gpu/drm/rockchip/rockchip_rgb.c
new file mode 100644
index 000000000000..96ac1458a59c
--- /dev/null
+++ b/drivers/gpu/drm/rockchip/rockchip_rgb.c
@@ -0,0 +1,173 @@
+//SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) Fuzhou Rockchip Electronics Co.Ltd
+ * Author:
+ *      Sandy Huang <hjc@rock-chips.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_dp_helper.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_of.h>
+
+#include <linux/component.h>
+#include <linux/of_graph.h>
+
+#include "rockchip_drm_drv.h"
+#include "rockchip_drm_vop.h"
+
+#define encoder_to_rgb(c) container_of(c, struct rockchip_rgb, encoder)
+
+struct rockchip_rgb {
+        struct device *dev;
+        struct drm_device *drm_dev;
+        struct drm_bridge *bridge;
+        struct drm_encoder encoder;
+        int output_mode;
+};
+
+static int
+rockchip_rgb_encoder_atomic_check(struct drm_encoder *encoder,
+                                   struct drm_crtc_state *crtc_state,
+                                   struct drm_connector_state *conn_state)
+{
+        struct rockchip_crtc_state *s = to_rockchip_crtc_state(crtc_state);
+        struct drm_connector *connector = conn_state->connector;
+        struct drm_display_info *info = &connector->display_info;
+        u32 bus_format;
+
+        if (info->num_bus_formats)
+                bus_format = info->bus_formats[0];
+        else
+                bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+
+        switch (bus_format) {
+        case MEDIA_BUS_FMT_RGB666_1X18:
+                s->output_mode = ROCKCHIP_OUT_MODE_P666;
+                break;
+        case MEDIA_BUS_FMT_RGB565_1X16:
+                s->output_mode = ROCKCHIP_OUT_MODE_P565;
+                break;
+        case MEDIA_BUS_FMT_RGB888_1X24:
+        case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
+        default:
+                s->output_mode = ROCKCHIP_OUT_MODE_P888;
+                break;
+        }
+
+        s->output_type = DRM_MODE_CONNECTOR_LVDS;
+
+        return 0;
+}
+
+static const
+struct drm_encoder_helper_funcs rockchip_rgb_encoder_helper_funcs = {
+        .atomic_check = rockchip_rgb_encoder_atomic_check,
+};
+
+static const struct drm_encoder_funcs rockchip_rgb_encoder_funcs = {
+        .destroy = drm_encoder_cleanup,
+};
+
+struct rockchip_rgb *rockchip_rgb_init(struct device *dev,
+                                       struct drm_crtc *crtc,
+                                       struct drm_device *drm_dev)
+{
+        struct rockchip_rgb *rgb;
+        struct drm_encoder *encoder;
+        struct device_node *port, *endpoint;
+        u32 endpoint_id;
+        int ret = 0, child_count = 0;
+        struct drm_panel *panel;
+        struct drm_bridge *bridge;
+
+        rgb = devm_kzalloc(dev, sizeof(*rgb), GFP_KERNEL);
+        if (!rgb)
+                return ERR_PTR(-ENOMEM);
+
+        rgb->dev = dev;
+        rgb->drm_dev = drm_dev;
+
+        port = of_graph_get_port_by_id(dev->of_node, 0);
+        if (!port)
+                return ERR_PTR(-EINVAL);
+
+        for_each_child_of_node(port, endpoint) {
+                if (of_property_read_u32(endpoint, "reg", &endpoint_id))
+                        endpoint_id = 0;
+
+                if (rockchip_drm_endpoint_is_subdriver(endpoint) > 0)
+                        continue;
+
+                child_count++;
+                ret = drm_of_find_panel_or_bridge(dev->of_node, 0, endpoint_id,
+                                                  &panel, &bridge);
+                if (!ret)
+                        break;
+        }
+
+        of_node_put(port);
+
+        /* if the rgb output is not connected to anything, just return */
+        if (!child_count)
+                return NULL;
+
+        if (ret < 0) {
+                if (ret != -EPROBE_DEFER)
+                        DRM_DEV_ERROR(dev, "failed to find panel or bridge %d\n", ret);
+                return ERR_PTR(ret);
+        }
+
+        encoder = &rgb->encoder;
+        encoder->possible_crtcs = drm_crtc_mask(crtc);
+
+        ret = drm_encoder_init(drm_dev, encoder, &rockchip_rgb_encoder_funcs,
+                               DRM_MODE_ENCODER_NONE, NULL);
+        if (ret < 0) {
+                DRM_DEV_ERROR(drm_dev->dev,
+                              "failed to initialize encoder: %d\n", ret);
+                return ERR_PTR(ret);
+        }
+
+        drm_encoder_helper_add(encoder, &rockchip_rgb_encoder_helper_funcs);
+
+        if (panel) {
+                bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_LVDS);
+                if (IS_ERR(bridge))
+                        return ERR_CAST(bridge);
+        }
+
+        rgb->bridge = bridge;
+
+        ret = drm_bridge_attach(encoder, rgb->bridge, NULL);
+        if (ret) {
+                DRM_DEV_ERROR(drm_dev->dev,
+                              "failed to attach bridge: %d\n", ret);
+                goto err_free_encoder;
+        }
+
+        return rgb;
+
+err_free_encoder:
+        drm_encoder_cleanup(encoder);
+        return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(rockchip_rgb_init);
+
+void rockchip_rgb_fini(struct rockchip_rgb *rgb)
+{
+        drm_panel_bridge_remove(rgb->bridge);
+        drm_encoder_cleanup(&rgb->encoder);
+}
+EXPORT_SYMBOL_GPL(rockchip_rgb_fini);
diff --git a/drivers/gpu/drm/rockchip/rockchip_rgb.h b/drivers/gpu/drm/rockchip/rockchip_rgb.h
new file mode 100644
index 000000000000..c712a673d1e3
--- /dev/null
+++ b/drivers/gpu/drm/rockchip/rockchip_rgb.h
@@ -0,0 +1,20 @@
+//SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) Fuzhou Rockchip Electronics Co.Ltd
+ * Author:
+ *      Sandy Huang <hjc@rock-chips.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+struct rockchip_rgb *rockchip_rgb_init(struct device *dev,
+                                       struct drm_crtc *crtc,
+                                       struct drm_device *drm_dev);
+void rockchip_rgb_fini(struct rockchip_rgb *rgb);