[RFC 4/8] drm: ingenic: add jz4780 Synopsys HDMI driver.

["H. Nikolaus Schaller" <hns@goldelico.com>]

From: Paul Boddie <paul@boddie.org.uk>

A specialisation of the generic Synopsys HDMI driver is employed for JZ4780
HDMI support. This requires a new driver, plus device tree and configuration
modifications.

Signed-off-by: Paul Boddie <paul@boddie.org.uk>
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
---
 drivers/gpu/drm/ingenic/Kconfig          |   8 ++
 drivers/gpu/drm/ingenic/Makefile         |   1 +
 drivers/gpu/drm/ingenic/dw_hdmi-jz4780.c | 120 +++++++++++++++++++++++
 3 files changed, 129 insertions(+)
 create mode 100644 drivers/gpu/drm/ingenic/dw_hdmi-jz4780.c

diff --git a/drivers/gpu/drm/ingenic/Kconfig b/drivers/gpu/drm/ingenic/Kconfig
index d82c3d37ec9c..44bfd0d35af1 100644
--- a/drivers/gpu/drm/ingenic/Kconfig
+++ b/drivers/gpu/drm/ingenic/Kconfig
@@ -14,3 +14,11 @@ config DRM_INGENIC
 	  Choose this option for DRM support for the Ingenic SoCs.
 
 	  If M is selected the module will be called ingenic-drm.
+
+config DRM_DW_HDMI_JZ4780
+	tristate "HDMI Support for Ingenic JZ4780"
+	depends on DRM_INGENIC
+	depends on OF
+	select DRM_DW_HDMI
+	help
+	  Choose this option for HDMI output from the Ingenic JZ4780.
diff --git a/drivers/gpu/drm/ingenic/Makefile b/drivers/gpu/drm/ingenic/Makefile
index 11cac42ce0bb..238383de63c7 100644
--- a/drivers/gpu/drm/ingenic/Makefile
+++ b/drivers/gpu/drm/ingenic/Makefile
@@ -1 +1,2 @@
 obj-$(CONFIG_DRM_INGENIC) += ingenic-drm.o
+obj-$(CONFIG_DRM_DW_HDMI_JZ4780) += dw_hdmi-jz4780.o
diff --git a/drivers/gpu/drm/ingenic/dw_hdmi-jz4780.c b/drivers/gpu/drm/ingenic/dw_hdmi-jz4780.c
new file mode 100644
index 000000000000..fa379e337263
--- /dev/null
+++ b/drivers/gpu/drm/ingenic/dw_hdmi-jz4780.c
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2011-2013 Freescale Semiconductor, Inc.
+ * Copyright (C) 2019 Paul Boddie <paul@boddie.org.uk>
+ *
+ * Derived from dw_hdmi-imx.c with i.MX portions removed.
+ * Probe and remove operations derived from rcar_dw_hdmi.c.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <drm/bridge/dw_hdmi.h>
+#include <drm/drm_of.h>
+
+static const struct dw_hdmi_mpll_config jz4780_mpll_cfg[] = {
+	{ 45250000,  { { 0x01e0, 0x0000 },
+		       { 0x21e1, 0x0000 },
+		       { 0x41e2, 0x0000 } } },
+	{ 92500000,  { { 0x0140, 0x0005 },
+		       { 0x2141, 0x0005 },
+		       { 0x4142, 0x0005 } } },
+	{ 148500000, { { 0x00a0, 0x000a },
+		       { 0x20a1, 0x000a },
+		       { 0x40a2, 0x000a } } },
+	{ 216000000, { { 0x00a0, 0x000a },
+		       { 0x2001, 0x000f },
+		       { 0x4002, 0x000f } } },
+	{ ~0UL,      { { 0x0000, 0x0000 },
+		       { 0x0000, 0x0000 },
+		       { 0x0000, 0x0000 } } }
+};
+
+static const struct dw_hdmi_curr_ctrl jz4780_cur_ctr[] = {
+	/*pixelclk     bpp8    bpp10   bpp12 */
+	{ 54000000,  { 0x091c, 0x091c, 0x06dc } },
+	{ 58400000,  { 0x091c, 0x06dc, 0x06dc } },
+	{ 72000000,  { 0x06dc, 0x06dc, 0x091c } },
+	{ 74250000,  { 0x06dc, 0x0b5c, 0x091c } },
+	{ 118800000, { 0x091c, 0x091c, 0x06dc } },
+	{ 216000000, { 0x06dc, 0x0b5c, 0x091c } },
+	{ ~0UL,      { 0x0000, 0x0000, 0x0000 } },
+};
+
+/*
+ * Resistance term 133Ohm Cfg
+ * PREEMP config 0.00
+ * TX/CK level 10
+ */
+static const struct dw_hdmi_phy_config jz4780_phy_config[] = {
+	/*pixelclk   symbol   term   vlev */
+	{ 216000000, 0x800d, 0x0005, 0x01ad},
+	{ ~0UL,      0x0000, 0x0000, 0x0000}
+};
+
+static enum drm_mode_status
+jz4780_hdmi_mode_valid(struct drm_connector *con,
+		       const struct drm_display_mode *mode)
+{
+	if (mode->clock < 13500)
+		return MODE_CLOCK_LOW;
+	/* FIXME: Hardware is capable of 270MHz, but setup data is missing. */
+	if (mode->clock > 216000)
+		return MODE_CLOCK_HIGH;
+
+	return MODE_OK;
+}
+
+static struct dw_hdmi_plat_data jz4780_dw_hdmi_plat_data = {
+	.mpll_cfg   = jz4780_mpll_cfg,
+	.cur_ctr    = jz4780_cur_ctr,
+	.phy_config = jz4780_phy_config,
+	.mode_valid = jz4780_hdmi_mode_valid,
+};
+
+static const struct of_device_id jz4780_dw_hdmi_dt_ids[] = {
+	{ .compatible = "ingenic,jz4780-dw-hdmi" },
+	{ /* Sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, jz4780_dw_hdmi_dt_ids);
+
+static int jz4780_dw_hdmi_probe(struct platform_device *pdev)
+{
+	struct dw_hdmi *hdmi;
+
+	hdmi = dw_hdmi_probe(pdev, &jz4780_dw_hdmi_plat_data);
+	if (IS_ERR(hdmi))
+		return PTR_ERR(hdmi);
+
+	platform_set_drvdata(pdev, hdmi);
+
+	return 0;
+}
+
+static int jz4780_dw_hdmi_remove(struct platform_device *pdev)
+{
+	struct dw_hdmi *hdmi = platform_get_drvdata(pdev);
+
+	dw_hdmi_remove(hdmi);
+
+	return 0;
+}
+
+static struct platform_driver jz4780_dw_hdmi_platform_driver = {
+	.probe  = jz4780_dw_hdmi_probe,
+	.remove = jz4780_dw_hdmi_remove,
+	.driver = {
+		.name = "dw-hdmi-jz4780",
+		.of_match_table = jz4780_dw_hdmi_dt_ids,
+	},
+};
+
+module_platform_driver(jz4780_dw_hdmi_platform_driver);
+
+MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com>");
+MODULE_AUTHOR("Yakir Yang <ykk@rock-chips.com>");
+MODULE_AUTHOR("Paul Boddie <paul@boddie.org.uk>");
+MODULE_DESCRIPTION("Ingenic JZ4780 DW-HDMI Driver Extension");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:dw-hdmi-jz4780");
-- 
2.23.0