drm/bridge: cdns-dsi: Add support for J721E wrapper

Add support for wrapper settings for DSI bridge on j721e. Also enable
DPI0

--------------- -----------------------
| -------| |------- |
| DSS | DPI2 |----->| DPI0 | DSI Wrapper |
| -------| |------- |
--------------- -----------------------

As shown above DPI2 output of DSS is connected to DPI0 input of DSI
Wrapper, DSI wrapper gives control wheather to enable/disable DPI0
input. In j721e above is the only configuration supported

Signed-off-by: Rahul T R <[e-mail]>
Reviewed-by: Tomi Valkeinen <[e-mail]>
Reviewed-by: Laurent Pinchart <[e-mail]>
Reviewed-by: Andrzej Hajda <[e-mail]>
Signed-off-by: Tomi Valkeinen <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/bridge/cadence/Kconfig

···
 	  Support Cadence DPI to DSI bridge. This is an internal
 	  bridge and is meant to be directly embedded in a SoC.
 
+if DRM_CDNS_DSI
+
+config DRM_CDNS_DSI_J721E
+	bool "J721E Cadence DSI wrapper support"
+	default y
+	help
+	  Support J721E Cadence DSI wrapper. The wrapper manages
+	  the routing of the DSS DPI signal to the Cadence DSI.
+endif
+
 config DRM_CDNS_MHDP8546
 	tristate "Cadence DPI/DP bridge"
 	select DRM_DISPLAY_DP_HELPER

drivers/gpu/drm/bridge/cadence/Makefile

···
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o
 cdns-dsi-y := cdns-dsi-core.o
+cdns-dsi-$(CONFIG_DRM_CDNS_DSI_J721E) += cdns-dsi-j721e.o
 obj-$(CONFIG_DRM_CDNS_MHDP8546) += cdns-mhdp8546.o
 cdns-mhdp8546-y := cdns-mhdp8546-core.o cdns-mhdp8546-hdcp.o
 cdns-mhdp8546-$(CONFIG_DRM_CDNS_MHDP8546_J721E) += cdns-mhdp8546-j721e.o

drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c

···
 #include <linux/iopoll.h>
 #include <linux/module.h>
 #include <linux/of_address.h>
+#include <linux/of_device.h>
 #include <linux/of_graph.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
···
 #include <linux/phy/phy-mipi-dphy.h>
 
 #include "cdns-dsi-core.h"
+#ifdef CONFIG_DRM_CDNS_DSI_J721E
+#include "cdns-dsi-j721e.h"
+#endif
 
 #define IP_CONF				0x0
 #define SP_HS_FIFO_DEPTH(x)		(((x) & GENMASK(30, 26)) >> 26)
···
 
 	val = readl(dsi->regs + MCTL_MAIN_EN) & ~IF_EN(input->id);
 	writel(val, dsi->regs + MCTL_MAIN_EN);
+
+	if (dsi->platform_ops && dsi->platform_ops->disable)
+		dsi->platform_ops->disable(dsi);
+
 	pm_runtime_put(dsi->base.dev);
 }
 
···
 
 	if (WARN_ON(pm_runtime_get_sync(dsi->base.dev) < 0))
 		return;
+
+	if (dsi->platform_ops && dsi->platform_ops->enable)
+		dsi->platform_ops->enable(dsi);
 
 	mode = &bridge->encoder->crtc->state->adjusted_mode;
 	nlanes = output->dev->lanes;
···
 		goto err_disable_pclk;
 	}
 
+	dsi->platform_ops = of_device_get_match_data(&pdev->dev);
+
 	val = readl(dsi->regs + IP_CONF);
 	dsi->direct_cmd_fifo_depth = 1 << (DIRCMD_FIFO_DEPTH(val) + 2);
 	dsi->rx_fifo_depth = RX_FIFO_DEPTH(val);
···
 	dsi->base.dev = &pdev->dev;
 	dsi->base.ops = &cdns_dsi_ops;
 
+	if (dsi->platform_ops && dsi->platform_ops->init) {
+		ret = dsi->platform_ops->init(dsi);
+		if (ret != 0) {
+			dev_err(&pdev->dev, "platform initialization failed: %d\n",
+				ret);
+			goto err_disable_runtime_pm;
+		}
+	}
+
 	ret = mipi_dsi_host_register(&dsi->base);
 	if (ret)
-		goto err_disable_runtime_pm;
+		goto err_deinit_platform;
 
 	clk_disable_unprepare(dsi->dsi_p_clk);
 
 	return 0;
+
+err_deinit_platform:
+	if (dsi->platform_ops && dsi->platform_ops->deinit)
+		dsi->platform_ops->deinit(dsi);
 
 err_disable_runtime_pm:
 	pm_runtime_disable(&pdev->dev);
···
 	struct cdns_dsi *dsi = platform_get_drvdata(pdev);
 
 	mipi_dsi_host_unregister(&dsi->base);
+
+	if (dsi->platform_ops && dsi->platform_ops->deinit)
+		dsi->platform_ops->deinit(dsi);
+
 	pm_runtime_disable(&pdev->dev);
 
 	return 0;
···
 
 static const struct of_device_id cdns_dsi_of_match[] = {
 	{ .compatible = "cdns,dsi" },
+#ifdef CONFIG_DRM_CDNS_DSI_J721E
+	{ .compatible = "ti,j721e-dsi", .data = &dsi_ti_j721e_ops, },
+#endif
 	{ },
 };
 MODULE_DEVICE_TABLE(of, cdns_dsi_of_match);

drivers/gpu/drm/bridge/cadence/cdns-dsi-core.h

···
 	struct drm_bridge bridge;
 };
 
+struct cdns_dsi;
+
+/**
+ * struct cdns_dsi_platform_ops - CDNS DSI Platform operations
+ * @init: Called in the CDNS DSI probe
+ * @deinit: Called in the CDNS DSI remove
+ * @enable: Called at the beginning of CDNS DSI bridge enable
+ * @disable: Called at the end of CDNS DSI bridge disable
+ */
+struct cdns_dsi_platform_ops {
+	int (*init)(struct cdns_dsi *dsi);
+	void (*deinit)(struct cdns_dsi *dsi);
+	void (*enable)(struct cdns_dsi *dsi);
+	void (*disable)(struct cdns_dsi *dsi);
+};
+
 struct cdns_dsi {
 	struct mipi_dsi_host base;
 	void __iomem *regs;
+#ifdef CONFIG_DRM_CDNS_DSI_J721E
+	void __iomem *j721e_regs;
+#endif
+	const struct cdns_dsi_platform_ops *platform_ops;
 	struct cdns_dsi_input input;
 	struct cdns_dsi_output output;
 	unsigned int direct_cmd_fifo_depth;

drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.c

···
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI j721e Cadence DSI wrapper
+ *
+ * Copyright (C) 2022 Texas Instruments Incorporated - http://www.ti.com/
+ * Author: Rahul T R <[e-mail]>
+ */
+
+#include <linux/io.h>
+#include <linux/platform_device.h>
+
+#include "cdns-dsi-j721e.h"
+
+#define DSI_WRAP_REVISION		0x0
+#define DSI_WRAP_DPI_CONTROL		0x4
+#define DSI_WRAP_DSC_CONTROL		0x8
+#define DSI_WRAP_DPI_SECURE		0xc
+#define DSI_WRAP_DSI_0_ASF_STATUS	0x10
+
+#define DSI_WRAP_DPI_0_EN		BIT(0)
+#define DSI_WRAP_DSI2_MUX_SEL		BIT(4)
+
+static int cdns_dsi_j721e_init(struct cdns_dsi *dsi)
+{
+	struct platform_device *pdev = to_platform_device(dsi->base.dev);
+
+	dsi->j721e_regs = devm_platform_ioremap_resource(pdev, 1);
+	return PTR_ERR_OR_ZERO(dsi->j721e_regs);
+}
+
+static void cdns_dsi_j721e_enable(struct cdns_dsi *dsi)
+{
+	/*
+	 * Enable DPI0 as its input. DSS0 DPI2 is connected
+	 * to DSI DPI0. This is the only supported configuration on
+	 * J721E.
+	 */
+	writel(DSI_WRAP_DPI_0_EN, dsi->j721e_regs + DSI_WRAP_DPI_CONTROL);
+}
+
+static void cdns_dsi_j721e_disable(struct cdns_dsi *dsi)
+{
+	/* Put everything to defaults  */
+	writel(0, dsi->j721e_regs + DSI_WRAP_DPI_CONTROL);
+}
+
+const struct cdns_dsi_platform_ops dsi_ti_j721e_ops = {
+	.init = cdns_dsi_j721e_init,
+	.enable = cdns_dsi_j721e_enable,
+	.disable = cdns_dsi_j721e_disable,
+};

drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * TI j721e Cadence DSI wrapper
+ *
+ * Copyright (C) 2022 Texas Instruments Incorporated - http://www.ti.com/
+ * Author: Rahul T R <[e-mail]>
+ */
+
+#ifndef __CDNS_DSI_J721E_H__
+#define __CDNS_DSI_J721E_H__
+
+#include "cdns-dsi-core.h"
+
+extern const struct cdns_dsi_platform_ops dsi_ti_j721e_ops;
+
+#endif /* !__CDNS_DSI_J721E_H__ */