drm/tidss: New driver for TI Keystone platform Display SubSystem

This patch adds a new DRM driver for Texas Instruments DSS IPs used on Texas Instruments Keystone K2G, AM65x, and J721e SoCs. The new DSS IP is a major change to the older DSS IP versions, which are supported by the omapdrm driver. While on higher level the Keystone DSS resembles the older DSS versions, the registers are completely different and the internal pipelines differ a lot.

DSS IP found on K2G is an "ultra-light" version, and has only a single plane and a single output. The Keystone 3 DSS IPs are found on AM65x and J721E SoCs. AM65x DSS has two video ports, one full video plane, and another "lite" plane without scaling support. J721E has 4 video ports, 2 video planes and 2 lite planes. AM65x DSS has also integrated OLDI (LVDS) output.

Co-developed-by Tomi Valkeinen <[email protected]>

Signed-off-by Jyri Sarha <[email protected]>

+++ b/drivers/gpu/drm/tidss/Kconfig

drivers/gpu/drm/tidss/Kconfig new file +8 -0

+	help
+	  The TI Keystone family SoCs introduced a new generation of
+	  Display SubSystem. There is currently three Keystone family
+	  SoCs released with DSS. Each with somewhat different version
+	  of it. The SoCs are 66AK2Gx, AM65x, and J721E. Set this to Y
+	  or M to add display support for TI Keystone family
+	  platforms.
 
 
+++ b/drivers/gpu/drm/tidss/tidss_crtc.c

drivers/gpu/drm/tidss/tidss_crtc.c new file +13 -0

+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_plane_helper.h>
+
+#include "tidss_crtc.h"
+#include "tidss_dispc.h"
+#include "tidss_drv.h"
+#include "tidss_irq.h"
+

drivers/gpu/drm/tidss/tidss_crtc.h new file +2 -0

@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*

drivers/gpu/drm/tidss/tidss_dispc.c new file +16 -0

@@ -0,0 +1,2645 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2016-2018 Texas Instruments Incorporated - http://www.ti.com/
+ * Author: Jyri Sarha <[email protected]>
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>

drivers/gpu/drm/tidss/tidss_dispc.c new file +41 -0

+
+#include "tidss_drv.h"
+#include "tidss_crtc.h"
+#include "tidss_plane.h"
+#include "tidss_irq.h"
+
+#include "tidss_scale_coefs.h"
+#include "tidss_dispc_regs.h"
+
+#include "tidss_dispc.h"
+
 
+
+enum c8_to_c12_mode { C8_TO_C12_REPLICATE, C8_TO_C12_MAX, C8_TO_C12_MIN };
+
+static u16 c8_to_c12(u8 c8, enum c8_to_c12_mode mode)
+{
+	u16 c12;
+
+	c12 = c8 << 4;
+
+	switch (mode) {
+	case C8_TO_C12_REPLICATE:
+		/* Copy c8 4 MSB to 4 LSB for full scale c12 */
+		c12 |= c8 >> 4;
+		break;
+	case C8_TO_C12_MAX:
+		c12 |= 0xF;
+		break;
+	default:
+	case C8_TO_C12_MIN:
+		break;
+	}
+
+	return c12;
+}
+
+static u64 argb8888_to_argb12121212(u32 argb8888, enum c8_to_c12_mode m)
+{
+	u8 a, r, g, b;
+	u64 v;
+

drivers/gpu/drm/tidss/tidss_drv.c new file +1 -0

new file mode 100644
index 000000000000..ba13b530214f
@@ -0,0 +1,292 @@
+// SPDX-License-Identifier: GPL-2.0

drivers/gpu/drm/tidss/tidss_drv.c new file +27 -0

+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_probe_helper.h>
+
+#include "tidss_dispc.h"
+#include "tidss_drv.h"
+#include "tidss_kms.h"
+#include "tidss_irq.h"
+
+/* Power management */
+
+int tidss_runtime_get(struct tidss_device *tidss)
+{
+	int r;
+
+	dev_dbg(tidss->dev, "%s\n", __func__);
+
+	r = pm_runtime_get_sync(tidss->dev);
+	WARN_ON(r < 0);
+	return r < 0 ? r : 0;
+}
+
+void tidss_runtime_put(struct tidss_device *tidss)

drivers/gpu/drm/tidss/tidss_drv.c new file +50 -0

+
+static int tidss_pm_runtime_suspend(struct device *dev)
+{
+	struct tidss_device *tidss = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	return dispc_runtime_suspend(tidss->dispc);
+}
+
+static int tidss_pm_runtime_resume(struct device *dev)
+{
+	struct tidss_device *tidss = dev_get_drvdata(dev);
+	int r;
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	r = dispc_runtime_resume(tidss->dispc);
+	if (r)
+		return r;
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tidss_suspend(struct device *dev)
+{
+	struct tidss_device *tidss = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	return drm_mode_config_helper_suspend(tidss->ddev);
+}
+
+static int tidss_resume(struct device *dev)
+{
+	struct tidss_device *tidss = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	return drm_mode_config_helper_resume(tidss->ddev);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops tidss_pm_ops = {
+	.runtime_suspend = tidss_pm_runtime_suspend,
+	.runtime_resume = tidss_pm_runtime_resume,
+	SET_SYSTEM_SLEEP_PM_OPS(tidss_suspend, tidss_resume)
+};
+

drivers/gpu/drm/tidss/tidss_drv.c new file +20 -0

+	.gem_free_object_unlocked = drm_gem_cma_free_object,
+	.gem_vm_ops		= &drm_gem_cma_vm_ops,
+	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd,
+	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle,
+	.gem_prime_import	= drm_gem_prime_import,
+	.gem_prime_export	= drm_gem_prime_export,
+	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
+	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
+	.gem_prime_vmap		= drm_gem_cma_prime_vmap,
+	.gem_prime_vunmap	= drm_gem_cma_prime_vunmap,
+	.gem_prime_mmap		= drm_gem_cma_prime_mmap,
+	.dumb_create		= drm_gem_cma_dumb_create,
+	.fops			= &tidss_fops,
+	.name			= "tidss",
+	.desc			= "TI Keystone DSS",
+	.date			= "20180215",
+	.major			= 1,
+	.minor			= 0,
+
+	.irq_preinstall		= tidss_irq_preinstall,

drivers/gpu/drm/tidss/tidss_drv.c new file +154 -0

+	int ret;
+	int irq;
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	tidss = devm_kzalloc(dev, sizeof(*tidss), GFP_KERNEL);
+	if (tidss == NULL)
+		return -ENOMEM;
+
+	tidss->dev = dev;
+	tidss->feat = of_device_get_match_data(dev);
+
+	platform_set_drvdata(pdev, tidss);
+
+	ddev = drm_dev_alloc(&tidss_driver, dev);
+	if (IS_ERR(ddev))
+		return PTR_ERR(ddev);
+
+	tidss->ddev = ddev;
+	ddev->dev_private = tidss;
+
+	pm_runtime_enable(dev);
+
+	ret = dispc_init(tidss);
+	if (ret) {
+		dev_err(dev, "failed to initialize dispc: %d\n", ret);
+		goto err_disable_pm;
+	}
+
+#ifndef CONFIG_PM
+	/* If we don't have PM, we need to call resume manually */
+	dispc_runtime_resume(tidss->dispc);
+#endif
+
+	ret = tidss_modeset_init(tidss);
+	if (ret < 0) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "failed to init DRM/KMS (%d)\n", ret);
+		goto err_runtime_suspend;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		ret = irq;
+		goto err_modeset_cleanup;
+	}
+
+	ret = drm_irq_install(ddev, irq);
+	if (ret) {
+		dev_err(dev, "drm_irq_install failed: %d\n", ret);
+		goto err_modeset_cleanup;
+	}
+
+	drm_kms_helper_poll_init(ddev);
+
+	ret = drm_dev_register(ddev, 0);
+	if (ret) {
+		dev_err(dev, "failed to register DRM device\n");
+		goto err_poll_fini;
+	}
+
+	drm_fbdev_generic_setup(ddev, 32);
+
+	dev_dbg(dev, "%s done\n", __func__);
+
+	return 0;
+
+err_poll_fini:
+	drm_kms_helper_poll_fini(ddev);
+
+	drm_atomic_helper_shutdown(ddev);
+
+	drm_irq_uninstall(ddev);
+
+err_modeset_cleanup:
+	tidss_modeset_cleanup(tidss);
+
+err_runtime_suspend:
+#ifndef CONFIG_PM
+	/* If we don't have PM, we need to call suspend manually */
+	dispc_runtime_suspend(tidss->dispc);
+#endif
+
+	dispc_remove(tidss);
+
+err_disable_pm:
+	pm_runtime_disable(dev);
+
+	drm_dev_put(ddev);
+
+	return ret;
+}
+
+static int tidss_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct tidss_device *tidss = platform_get_drvdata(pdev);
+	struct drm_device *ddev = tidss->ddev;
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	drm_dev_unregister(ddev);
+
+	drm_kms_helper_poll_fini(ddev);
+
+	drm_atomic_helper_shutdown(ddev);
+
+	drm_irq_uninstall(ddev);
+
+	tidss_modeset_cleanup(tidss);
+
+#ifndef CONFIG_PM
+	/* If we don't have PM, we need to call suspend manually */
+	dispc_runtime_suspend(tidss->dispc);
+#endif
+
+	dispc_remove(tidss);
+
+	pm_runtime_disable(dev);
+
+	drm_dev_put(ddev);
+
+	dev_dbg(dev, "%s done\n", __func__);
+
+	return 0;
+}
+
+static const struct of_device_id tidss_of_table[] = {
+	{ .compatible = "ti,k2g-dss", .data = &dispc_k2g_feats, },
+	{ .compatible = "ti,am65x-dss", .data = &dispc_am65x_feats, },
+	{ .compatible = "ti,j721e-dss", .data = &dispc_j721e_feats, },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, tidss_of_table);
+
+static struct platform_driver tidss_platform_driver = {
+	.probe		= tidss_probe,
+	.remove		= tidss_remove,
+	.driver		= {
+		.name	= "tidss",
+#ifdef CONFIG_PM
+		.pm	= &tidss_pm_ops,
+#endif
+		.of_match_table = tidss_of_table,
+		.suppress_bind_attrs = true,
+	},
+};
+
+module_platform_driver(tidss_platform_driver);
+
+MODULE_AUTHOR("Tomi Valkeinen <[email protected]>");
+MODULE_DESCRIPTION("TI Keystone DSS Driver");
+MODULE_LICENSE("GPL v2");

drivers/gpu/drm/tidss/tidss_drv.h new file +11 -0

new file mode 100644
index 000000000000..ef815c840b44
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
+ * Author: Tomi Valkeinen <[email protected]>
+ */
+
+#ifndef __TIDSS_DRV_H__
+#define __TIDSS_DRV_H__
+
+#include <linux/spinlock.h>
+

drivers/gpu/drm/tidss/tidss_drv.h new file +21 -0

+
+	const struct dispc_features *feat;
+	struct dispc_device *dispc;
+
+	unsigned int num_crtcs;
+	struct drm_crtc *crtcs[TIDSS_MAX_PORTS];
+
+	unsigned int num_planes;
+	struct drm_plane *planes[TIDSS_MAX_PLANES];
+
+	spinlock_t wait_lock;	/* protects the irq masks */
+	dispc_irq_t irq_mask;	/* enabled irqs in addition to wait_list */
+	dispc_irq_t irq_uf_mask; /* underflow irq bits for all planes */
+
+	struct drm_atomic_state *saved_state;
+};
+
+int tidss_runtime_get(struct tidss_device *tidss);
+void tidss_runtime_put(struct tidss_device *tidss);
+
+#endif

drivers/gpu/drm/tidss/tidss_encoder.c new file +0 -0

new file mode 100644
index 000000000000..7390c056b257

drivers/gpu/drm/tidss/tidss_encoder.c new file +76 -0

+
+#include "tidss_drv.h"
+#include "tidss_encoder.h"
+#include "tidss_crtc.h"
+
+static int tidss_encoder_atomic_check(struct drm_encoder *encoder,
+				      struct drm_crtc_state *crtc_state,
+				      struct drm_connector_state *conn_state)
+{
+	struct drm_device *ddev = encoder->dev;
+	struct tidss_crtc_state *tcrtc_state = to_tidss_crtc_state(crtc_state);
+	struct drm_display_info *di = &conn_state->connector->display_info;
+	struct drm_bridge *bridge;
+	bool bus_flags_set = false;
+
+	dev_dbg(ddev->dev, "%s\n", __func__);
+
+	/*
+	 * Take the bus_flags from the first bridge that defines
+	 * bridge timings, or from the connector's display_info if no
+	 * bridge defines the timings.
+	 */
+	for (bridge = encoder->bridge; bridge; bridge = bridge->next) {
+		if (!bridge->timings)
+			continue;
+
+		tcrtc_state->bus_flags = bridge->timings->input_bus_flags;
+		bus_flags_set = true;
+		break;
+	}
+
+	if (!di->bus_formats || di->num_bus_formats == 0)  {
+		dev_err(ddev->dev, "%s: No bus_formats in connected display\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	// XXX any cleaner way to set bus format and flags?
+	tcrtc_state->bus_format = di->bus_formats[0];
+	if (!bus_flags_set)
+		tcrtc_state->bus_flags = di->bus_flags;
+
+	return 0;
+}
+
+static const struct drm_encoder_helper_funcs encoder_helper_funcs = {
+	.atomic_check = tidss_encoder_atomic_check,
+};
+
+static const struct drm_encoder_funcs encoder_funcs = {
+	.destroy = drm_encoder_cleanup,
+};
+
+struct drm_encoder *tidss_encoder_create(struct tidss_device *tidss,
+					 u32 encoder_type, u32 possible_crtcs)
+{
+	struct drm_encoder *enc;
+	int ret;
+
+	enc = devm_kzalloc(tidss->dev, sizeof(*enc), GFP_KERNEL);
+	if (!enc)
+		return ERR_PTR(-ENOMEM);
+
+	enc->possible_crtcs = possible_crtcs;
+
+	ret = drm_encoder_init(tidss->ddev, enc, &encoder_funcs,
+			       encoder_type, NULL);
+	if (ret < 0)
+		return ERR_PTR(ret);
+
+	drm_encoder_helper_add(enc, &encoder_helper_funcs);
+
+	dev_dbg(tidss->dev, "Encoder create done\n");
+
+	return enc;
+}

drivers/gpu/drm/tidss/tidss_encoder.h new file +17 -0

new file mode 100644
index 000000000000..06854d66e7e6
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
+ * Author: Tomi Valkeinen <[email protected]>
+ */
+
+#ifndef __TIDSS_ENCODER_H__
+#define __TIDSS_ENCODER_H__
+
+#include <drm/drm_encoder.h>
+
+struct tidss_device;
+
+struct drm_encoder *tidss_encoder_create(struct tidss_device *tidss,
+					 u32 encoder_type, u32 possible_crtcs);
+
+#endif

drivers/gpu/drm/tidss/tidss_irq.c new file +0 -0

new file mode 100644
index 000000000000..001cac7c1355

Hi Jyri.

Took a quick look - looks like a very nice driver. Some drive by comments below.

I was left with the impression that there is a lot of code to support vblank - and I wonder if there is some general code that can help you here that you have missed.

Sam

Quoted 17 lines · Jyri Sarha

This patch adds a new DRM driver for Texas Instruments DSS IPs used on Texas Instruments Keystone K2G, AM65x, and J721e SoCs. The new DSS IP is a major change to the older DSS IP versions, which are supported by the omapdrm driver. While on higher level the Keystone DSS resembles the older DSS versions, the registers are completely different and the internal pipelines differ a lot.

DSS IP found on K2G is an "ultra-light" version, and has only a single plane and a single output. The Keystone 3 DSS IPs are found on AM65x and J721E SoCs. AM65x DSS has two video ports, one full video plane, and another "lite" plane without scaling support. J721E has 4 video ports, 2 video planes and 2 lite planes. AM65x DSS has also integrated OLDI (LVDS) output.

Co-developed-by Tomi Valkeinen <[email protected]>

Signed-off-by Jyri Sarha <[email protected]>

+++ b/drivers/gpu/drm/tidss/Kconfig

drivers/gpu/drm/tidss/tidss_dispc.c line 5

Quoted 8 lines

drivers/gpu/drm/tidss/tidss_dispc.c new file +5 -0

@@ -0,0 +1,2645 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2016-2018 Texas Instruments Incorporated - http://www.ti.com/
+ * Author: Jyri Sarha <[email protected]>
+ */

Quoted 33 lines

drivers/gpu/drm/tidss/tidss_dispc.c new file +33 -0

+enum c8_to_c12_mode { C8_TO_C12_REPLICATE, C8_TO_C12_MAX, C8_TO_C12_MIN };
+
+static u16 c8_to_c12(u8 c8, enum c8_to_c12_mode mode)
+{
+	u16 c12;
+
+	c12 = c8 << 4;
+
+	switch (mode) {
+	case C8_TO_C12_REPLICATE:
+		/* Copy c8 4 MSB to 4 LSB for full scale c12 */
+		c12 |= c8 >> 4;
+		break;
+	case C8_TO_C12_MAX:
+		c12 |= 0xF;
+		break;
+	default:
+	case C8_TO_C12_MIN:
+		break;
+	}
+
+	return c12;
+}
+
+static u64 argb8888_to_argb12121212(u32 argb8888, enum c8_to_c12_mode m)
+{
+	u8 a, r, g, b;
+	u64 v;
+
+	a = (argb8888 >> 24) & 0xff;
+	r = (argb8888 >> 16) & 0xff;
+	g = (argb8888 >> 8) & 0xff;
+	b = (argb8888 >> 0) & 0xff;

drivers/gpu/drm/tidss/tidss_dispc.c line 1058

Quoted 6 lines

drivers/gpu/drm/tidss/tidss_dispc.c new file +6 -0

+
+	v = ((u64)c8_to_c12(a, m) << 36) | ((u64)c8_to_c12(r, m) << 24) |
+		((u64)c8_to_c12(g, m) << 12) | (u64)c8_to_c12(b, m);
+
+	return v;
+}

This looks like a helper that could be useful for others. Maybe move up one level?

drivers/gpu/drm/tidss/tidss_drv.c

Quoted 5 lines

drivers/gpu/drm/tidss/tidss_drv.c new file +0 -0

new file mode 100644
index 000000000000..ba13b530214f

drivers/gpu/drm/tidss/tidss_drv.c line 108

Quoted 6 lines

drivers/gpu/drm/tidss/tidss_drv.c new file +6 -0

+/* DRM device Information */
+DEFINE_DRM_GEM_CMA_FOPS(tidss_fops);
+
+static struct drm_driver tidss_driver = {
+	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC |
+					DRIVER_HAVE_IRQ,

DRIVER_HAVE_IRQ is only for legacy drivers.

In general - look through the comments in drm_drv.h - and remove use of all obsoleted callbacks.
I checked .gem_free_object_unlocked - it is deprecated. I guess there is more.

Quoted 24 lines

drivers/gpu/drm/tidss/tidss_drv.c new file +24 -0

+	.gem_free_object_unlocked = drm_gem_cma_free_object,
+	.gem_vm_ops		= &drm_gem_cma_vm_ops,
+	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd,
+	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle,
+	.gem_prime_import	= drm_gem_prime_import,
+	.gem_prime_export	= drm_gem_prime_export,
+	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
+	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
+	.gem_prime_vmap		= drm_gem_cma_prime_vmap,
+	.gem_prime_vunmap	= drm_gem_cma_prime_vunmap,
+	.gem_prime_mmap		= drm_gem_cma_prime_mmap,
+	.dumb_create		= drm_gem_cma_dumb_create,
+	.fops			= &tidss_fops,
+	.name			= "tidss",
+	.desc			= "TI Keystone DSS",
+	.date			= "20180215",
+	.major			= 1,
+	.minor			= 0,
+
+	.irq_preinstall		= tidss_irq_preinstall,
+	.irq_postinstall	= tidss_irq_postinstall,
+	.irq_handler		= tidss_irq_handler,
+	.irq_uninstall		= tidss_irq_uninstall,
+};

drivers/gpu/drm/tidss/tidss_drv.c line 138

Quoted 6 lines

drivers/gpu/drm/tidss/tidss_drv.c new file +6 -0

+
+static int tidss_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct tidss_device *tidss;
+	struct drm_device *ddev;

See code example in drm_drv.c how to embed drm_device. This is the preferred approach these days.

Quoted 159 lines

drivers/gpu/drm/tidss/tidss_drv.c new file +154 -0

+	int ret;
+	int irq;
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	tidss = devm_kzalloc(dev, sizeof(*tidss), GFP_KERNEL);
+	if (tidss == NULL)
+		return -ENOMEM;
+
+	tidss->dev = dev;
+	tidss->feat = of_device_get_match_data(dev);
+
+	platform_set_drvdata(pdev, tidss);
+
+	ddev = drm_dev_alloc(&tidss_driver, dev);
+	if (IS_ERR(ddev))
+		return PTR_ERR(ddev);
+
+	tidss->ddev = ddev;
+	ddev->dev_private = tidss;
+
+	pm_runtime_enable(dev);
+
+	ret = dispc_init(tidss);
+	if (ret) {
+		dev_err(dev, "failed to initialize dispc: %d\n", ret);
+		goto err_disable_pm;
+	}
+
+#ifndef CONFIG_PM
+	/* If we don't have PM, we need to call resume manually */
+	dispc_runtime_resume(tidss->dispc);
+#endif
+
+	ret = tidss_modeset_init(tidss);
+	if (ret < 0) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "failed to init DRM/KMS (%d)\n", ret);
+		goto err_runtime_suspend;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		ret = irq;
+		goto err_modeset_cleanup;
+	}
+
+	ret = drm_irq_install(ddev, irq);
+	if (ret) {
+		dev_err(dev, "drm_irq_install failed: %d\n", ret);
+		goto err_modeset_cleanup;
+	}
+
+	drm_kms_helper_poll_init(ddev);
+
+	ret = drm_dev_register(ddev, 0);
+	if (ret) {
+		dev_err(dev, "failed to register DRM device\n");
+		goto err_poll_fini;
+	}
+
+	drm_fbdev_generic_setup(ddev, 32);
+
+	dev_dbg(dev, "%s done\n", __func__);
+
+	return 0;
+
+err_poll_fini:
+	drm_kms_helper_poll_fini(ddev);
+
+	drm_atomic_helper_shutdown(ddev);
+
+	drm_irq_uninstall(ddev);
+
+err_modeset_cleanup:
+	tidss_modeset_cleanup(tidss);
+
+err_runtime_suspend:
+#ifndef CONFIG_PM
+	/* If we don't have PM, we need to call suspend manually */
+	dispc_runtime_suspend(tidss->dispc);
+#endif
+
+	dispc_remove(tidss);
+
+err_disable_pm:
+	pm_runtime_disable(dev);
+
+	drm_dev_put(ddev);
+
+	return ret;
+}
+
+static int tidss_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct tidss_device *tidss = platform_get_drvdata(pdev);
+	struct drm_device *ddev = tidss->ddev;
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	drm_dev_unregister(ddev);
+
+	drm_kms_helper_poll_fini(ddev);
+
+	drm_atomic_helper_shutdown(ddev);
+
+	drm_irq_uninstall(ddev);
+
+	tidss_modeset_cleanup(tidss);
+
+#ifndef CONFIG_PM
+	/* If we don't have PM, we need to call suspend manually */
+	dispc_runtime_suspend(tidss->dispc);
+#endif
+
+	dispc_remove(tidss);
+
+	pm_runtime_disable(dev);
+
+	drm_dev_put(ddev);
+
+	dev_dbg(dev, "%s done\n", __func__);
+
+	return 0;
+}
+
+static const struct of_device_id tidss_of_table[] = {
+	{ .compatible = "ti,k2g-dss", .data = &dispc_k2g_feats, },
+	{ .compatible = "ti,am65x-dss", .data = &dispc_am65x_feats, },
+	{ .compatible = "ti,j721e-dss", .data = &dispc_j721e_feats, },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, tidss_of_table);
+
+static struct platform_driver tidss_platform_driver = {
+	.probe		= tidss_probe,
+	.remove		= tidss_remove,
+	.driver		= {
+		.name	= "tidss",
+#ifdef CONFIG_PM
+		.pm	= &tidss_pm_ops,
+#endif
+		.of_match_table = tidss_of_table,
+		.suppress_bind_attrs = true,
+	},
+};
+
+module_platform_driver(tidss_platform_driver);
+
+MODULE_AUTHOR("Tomi Valkeinen <[email protected]>");
+MODULE_DESCRIPTION("TI Keystone DSS Driver");
+MODULE_LICENSE("GPL v2");

drivers/gpu/drm/tidss/tidss_drv.h new file +0 -0

new file mode 100644
index 000000000000..ef815c840b44

I am not so sure if the DSS go-bit functionality (hw support to commit changes to display during next vertical blank) so widely used concept that it would make sense to make drm wide helpers to handle it.