[15/23] drm/sun4i: Add LVDS support

diff --git a/drivers/gpu/drm/sun4i/Makefile b/drivers/gpu/drm/sun4i/Makefile
index cfba2c07519c..6fee15d016ef 100644
--- a/drivers/gpu/drm/sun4i/Makefile
+++ b/drivers/gpu/drm/sun4i/Makefile
@@ -10,6 +10,7 @@  sun4i-drm-hdmi-y		+= sun4i_hdmi_tmds_clk.o
 
 sun4i-tcon-y			+= sun4i_tcon.o
 sun4i-tcon-y			+= sun4i_rgb.o
+sun4i-tcon-y			+= sun4i_lvds.o
 sun4i-tcon-y			+= sun4i_dotclock.o
 sun4i-tcon-y			+= sun4i_crtc.o
 
diff --git a/drivers/gpu/drm/sun4i/sun4i_lvds.c b/drivers/gpu/drm/sun4i/sun4i_lvds.c
new file mode 100644
index 000000000000..635a3f505ecb
--- /dev/null
+++ b/drivers/gpu/drm/sun4i/sun4i_lvds.c
@@ -0,0 +1,183 @@ 
+/*
+ * Copyright (C) 2015 NextThing Co
+ * Copyright (C) 2015-2017 Free Electrons
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+
+#include "sun4i_crtc.h"
+#include "sun4i_tcon.h"
+#include "sun4i_lvds.h"
+
+struct sun4i_lvds {
+	struct drm_connector	connector;
+	struct drm_encoder	encoder;
+
+	struct sun4i_tcon	*tcon;
+};
+
+static inline struct sun4i_lvds *
+drm_connector_to_sun4i_lvds(struct drm_connector *connector)
+{
+	return container_of(connector, struct sun4i_lvds,
+			    connector);
+}
+
+static inline struct sun4i_lvds *
+drm_encoder_to_sun4i_lvds(struct drm_encoder *encoder)
+{
+	return container_of(encoder, struct sun4i_lvds,
+			    encoder);
+}
+
+static int sun4i_lvds_get_modes(struct drm_connector *connector)
+{
+	struct sun4i_lvds *lvds =
+		drm_connector_to_sun4i_lvds(connector);
+	struct sun4i_tcon *tcon = lvds->tcon;
+
+	return drm_panel_get_modes(tcon->panel);
+}
+
+static struct drm_connector_helper_funcs sun4i_lvds_con_helper_funcs = {
+	.get_modes	= sun4i_lvds_get_modes,
+};
+
+static void
+sun4i_lvds_connector_destroy(struct drm_connector *connector)
+{
+	struct sun4i_lvds *lvds = drm_connector_to_sun4i_lvds(connector);
+	struct sun4i_tcon *tcon = lvds->tcon;
+
+	drm_panel_detach(tcon->panel);
+	drm_connector_cleanup(connector);
+}
+
+static const struct drm_connector_funcs sun4i_lvds_con_funcs = {
+	.fill_modes		= drm_helper_probe_single_connector_modes,
+	.destroy		= sun4i_lvds_connector_destroy,
+	.reset			= drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
+};
+
+static void sun4i_lvds_encoder_enable(struct drm_encoder *encoder)
+{
+	struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
+	struct sun4i_tcon *tcon = lvds->tcon;
+
+	DRM_DEBUG_DRIVER("Enabling LVDS output\n");
+
+	if (!IS_ERR(tcon->panel)) {
+		drm_panel_prepare(tcon->panel);
+		drm_panel_enable(tcon->panel);
+	}
+}
+
+static void sun4i_lvds_encoder_disable(struct drm_encoder *encoder)
+{
+	struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
+	struct sun4i_tcon *tcon = lvds->tcon;
+
+	DRM_DEBUG_DRIVER("Disabling LVDS output\n");
+
+	if (!IS_ERR(tcon->panel)) {
+		drm_panel_disable(tcon->panel);
+		drm_panel_unprepare(tcon->panel);
+	}
+}
+
+static const struct drm_encoder_helper_funcs sun4i_lvds_enc_helper_funcs = {
+	.disable	= sun4i_lvds_encoder_disable,
+	.enable		= sun4i_lvds_encoder_enable,
+};
+
+static const struct drm_encoder_funcs sun4i_lvds_enc_funcs = {
+	.destroy	= drm_encoder_cleanup,
+};
+
+int sun4i_lvds_init(struct drm_device *drm, struct sun4i_tcon *tcon)
+{
+	struct drm_encoder *encoder;
+	struct drm_bridge *bridge;
+	struct sun4i_lvds *lvds;
+	int ret;
+
+	lvds = devm_kzalloc(drm->dev, sizeof(*lvds), GFP_KERNEL);
+	if (!lvds)
+		return -ENOMEM;
+	lvds->tcon = tcon;
+	encoder = &lvds->encoder;
+
+	ret = drm_of_find_panel_or_bridge(tcon->dev->of_node, 1, 0,
+					  &tcon->panel, &bridge);
+	if (ret) {
+		dev_info(drm->dev, "No panel or bridge found... LVDS output disabled\n");
+		return 0;
+	}
+
+	drm_encoder_helper_add(&lvds->encoder,
+			       &sun4i_lvds_enc_helper_funcs);
+	ret = drm_encoder_init(drm,
+			       &lvds->encoder,
+			       &sun4i_lvds_enc_funcs,
+			       DRM_MODE_ENCODER_LVDS,
+			       NULL);
+	if (ret) {
+		dev_err(drm->dev, "Couldn't initialise the lvds encoder\n");
+		goto err_out;
+	}
+
+	/* The LVDS encoder can only work with the TCON channel 0 */
+	lvds->encoder.possible_crtcs = BIT(drm_crtc_index(&tcon->crtc->crtc));
+
+	if (tcon->panel) {
+		drm_connector_helper_add(&lvds->connector,
+					 &sun4i_lvds_con_helper_funcs);
+		ret = drm_connector_init(drm, &lvds->connector,
+					 &sun4i_lvds_con_funcs,
+					 DRM_MODE_CONNECTOR_LVDS);
+		if (ret) {
+			dev_err(drm->dev, "Couldn't initialise the lvds connector\n");
+			goto err_cleanup_connector;
+		}
+
+		drm_mode_connector_attach_encoder(&lvds->connector,
+						  &lvds->encoder);
+
+		ret = drm_panel_attach(tcon->panel, &lvds->connector);
+		if (ret) {
+			dev_err(drm->dev, "Couldn't attach our panel\n");
+			goto err_cleanup_connector;
+		}
+	}
+
+	if (bridge) {
+		ret = drm_bridge_attach(encoder, bridge, NULL);
+		if (ret) {
+			dev_err(drm->dev, "Couldn't attach our bridge\n");
+			goto err_cleanup_connector;
+		}
+	}
+
+	return 0;
+
+err_cleanup_connector:
+	drm_encoder_cleanup(&lvds->encoder);
+err_out:
+	return ret;
+}
+EXPORT_SYMBOL(sun4i_lvds_init);
diff --git a/drivers/gpu/drm/sun4i/sun4i_lvds.h b/drivers/gpu/drm/sun4i/sun4i_lvds.h
new file mode 100644
index 000000000000..1b8fad4b82c3
--- /dev/null
+++ b/drivers/gpu/drm/sun4i/sun4i_lvds.h
@@ -0,0 +1,18 @@ 
+/*
+ * Copyright (C) 2015 NextThing Co
+ * Copyright (C) 2015-2017 Free Electrons
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ */
+
+#ifndef _SUN4I_LVDS_H_
+#define _SUN4I_LVDS_H_
+
+int sun4i_lvds_init(struct drm_device *drm, struct sun4i_tcon *tcon);
+
+#endif /* _SUN4I_LVDS_H_ */
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index 3efa1ab045cd..6a20a467ee6d 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -31,10 +31,52 @@ 
 #include "sun4i_crtc.h"
 #include "sun4i_dotclock.h"
 #include "sun4i_drv.h"
+#include "sun4i_lvds.h"
 #include "sun4i_rgb.h"
 #include "sun4i_tcon.h"
 #include "sunxi_engine.h"
 
+static struct drm_connector *sun4i_tcon_get_connector(const struct drm_encoder *encoder)
+{
+	struct drm_connector *connector;
+	struct drm_connector_list_iter iter;
+
+	drm_connector_list_iter_begin(encoder->dev, &iter);
+	drm_for_each_connector_iter(connector, &iter)
+		if (connector->encoder == encoder) {
+			drm_connector_list_iter_end(&iter);
+			return connector;
+		}
+	drm_connector_list_iter_end(&iter);
+
+	return NULL;
+}
+
+static int sun4i_tcon_get_pixel_depth(const struct drm_encoder *encoder)
+{
+	struct drm_connector *connector;
+	struct drm_display_info *info;
+
+	connector = sun4i_tcon_get_connector(encoder);
+	if (!connector)
+		return -EINVAL;
+
+	info = &connector->display_info;
+	if (info->num_bus_formats != 1)
+		return -EINVAL;
+
+	switch (info->bus_formats[0]) {
+	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
+		return 18;
+
+	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
+	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
+		return 24;
+	}
+
+	return -EINVAL;
+}
+
 static void sun4i_tcon_channel_set_status(struct sun4i_tcon *tcon, int channel,
 					  bool enabled)
 {
@@ -69,9 +111,13 @@  void sun4i_tcon_set_status(struct sun4i_tcon *tcon,
 			   const struct drm_encoder *encoder,
 			   bool enabled)
 {
+	bool is_lvds = false;
 	int channel;
 
 	switch (encoder->encoder_type) {
+	case DRM_MODE_ENCODER_LVDS:
+		is_lvds = true;
+		/* Fallthrough */
 	case DRM_MODE_ENCODER_NONE:
 		channel = 0;
 		break;
@@ -84,10 +130,47 @@  void sun4i_tcon_set_status(struct sun4i_tcon *tcon,
 		return;
 	}
 
+	if (is_lvds && !enabled)
+		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_IF_REG,
+				   SUN4I_TCON0_LVDS_IF_EN, 0);
+
 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
 			   SUN4I_TCON_GCTL_TCON_ENABLE,
 			   enabled ? SUN4I_TCON_GCTL_TCON_ENABLE : 0);
 
+	if (is_lvds && enabled) {
+		u8 val;
+
+		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_IF_REG,
+				   SUN4I_TCON0_LVDS_IF_EN,
+				   SUN4I_TCON0_LVDS_IF_EN);
+
+		regmap_write(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
+			     SUN4I_TCON0_LVDS_ANA0_C(2) |
+			     SUN4I_TCON0_LVDS_ANA0_V(3) |
+			     SUN4I_TCON0_LVDS_ANA0_PD(2) |
+			     SUN4I_TCON0_LVDS_ANA0_EN_LDO);
+		udelay(2);
+
+		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
+				   SUN4I_TCON0_LVDS_ANA0_EN_MB,
+				   SUN4I_TCON0_LVDS_ANA0_EN_MB);
+		udelay(2);
+
+		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
+				   SUN4I_TCON0_LVDS_ANA0_EN_DRVC,
+				   SUN4I_TCON0_LVDS_ANA0_EN_DRVC);
+
+		if (sun4i_tcon_get_pixel_depth(encoder) == 18)
+			val = 7;
+		else
+			val = 0xf;
+
+		regmap_write_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
+				  SUN4I_TCON0_LVDS_ANA0_EN_DRVD(0xf),
+				  SUN4I_TCON0_LVDS_ANA0_EN_DRVD(val));
+	}
+
 	sun4i_tcon_channel_set_status(tcon, channel, enabled);
 }
 
@@ -170,6 +253,78 @@  static void sun4i_tcon0_mode_set_common(struct sun4i_tcon *tcon,
 		     SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay));
 }
 
+static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon,
+				      const struct drm_encoder *encoder,
+				      const struct drm_display_mode *mode)
+{
+	unsigned int bp;
+	u8 clk_delay;
+	u32 reg, val = 0;
+
+	tcon->dclk_min_div = 7;
+	tcon->dclk_max_div = 7;
+	sun4i_tcon0_mode_set_common(tcon, mode);
+
+	/* Adjust clock delay */
+	clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
+	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
+			   SUN4I_TCON0_CTL_CLK_DELAY_MASK,
+			   SUN4I_TCON0_CTL_CLK_DELAY(clk_delay));
+
+	/*
+	 * This is called a backporch in the register documentation,
+	 * but it really is the back porch + hsync
+	 */
+	bp = mode->crtc_htotal - mode->crtc_hsync_start;
+	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
+			 mode->crtc_htotal, bp);
+
+	/* Set horizontal display timings */
+	regmap_write(tcon->regs, SUN4I_TCON0_BASIC1_REG,
+		     SUN4I_TCON0_BASIC1_H_TOTAL(0x554) |
+		     SUN4I_TCON0_BASIC1_H_BACKPORCH(0xa0));
+
+	/*
+	 * This is called a backporch in the register documentation,
+	 * but it really is the back porch + hsync
+	 */
+	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
+	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
+			 mode->crtc_vtotal, bp);
+
+	/* Set vertical display timings */
+	regmap_write(tcon->regs, SUN4I_TCON0_BASIC2_REG,
+		     SUN4I_TCON0_BASIC2_V_TOTAL(mode->crtc_vtotal * 2) |
+		     SUN4I_TCON0_BASIC2_V_BACKPORCH(0x17));
+
+	reg = SUN4I_TCON0_LVDS_IF_CLK_SEL_TCON0 |
+		SUN4I_TCON0_LVDS_IF_DATA_POL_NORMAL |
+		SUN4I_TCON0_LVDS_IF_CLK_POL_NORMAL;
+	if (sun4i_tcon_get_pixel_depth(encoder) == 24)
+		reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS;
+	else
+		reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_18BITS;
+
+	regmap_write(tcon->regs, SUN4I_TCON0_LVDS_IF_REG, reg);
+
+	/* Setup the polarity of the various signals */
+	if (!(mode->flags & DRM_MODE_FLAG_PHSYNC))
+		val |= SUN4I_TCON0_IO_POL_HSYNC_POSITIVE;
+
+	if (!(mode->flags & DRM_MODE_FLAG_PVSYNC))
+		val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
+
+	regmap_write(tcon->regs, SUN4I_TCON0_IO_POL_REG, 0);
+
+	/* Map output pins to channel 0 */
+	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
+			   SUN4I_TCON_GCTL_IOMAP_MASK,
+			   SUN4I_TCON_GCTL_IOMAP_TCON0);
+
+	/* Enable the output on the pins */
+	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, 0xe0000000);
+}
+
 static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
 				     const struct drm_display_mode *mode)
 {
@@ -336,6 +491,9 @@  void sun4i_tcon_mode_set(struct sun4i_tcon *tcon,
 			 const struct drm_display_mode *mode)
 {
 	switch (encoder->encoder_type) {
+	case DRM_MODE_ENCODER_LVDS:
+		sun4i_tcon0_mode_set_lvds(tcon, encoder, mode);
+		break;
 	case DRM_MODE_ENCODER_NONE:
 		sun4i_tcon0_mode_set_rgb(tcon, mode);
 		sun4i_tcon_set_mux(tcon, 0, encoder);
@@ -667,7 +825,9 @@  static int sun4i_tcon_bind(struct device *dev, struct device *master,
 	struct drm_device *drm = data;
 	struct sun4i_drv *drv = drm->dev_private;
 	struct sunxi_engine *engine;
+	struct device_node *remote;
 	struct sun4i_tcon *tcon;
+	bool has_lvds;
 	int ret;
 
 	engine = sun4i_tcon_find_engine(drv, dev->of_node);
@@ -698,6 +858,26 @@  static int sun4i_tcon_bind(struct device *dev, struct device *master,
 		return ret;
 	}
 
+	/*
+	 * This can only be made optional since we've had DT nodes
+	 * without the LVDS reset properties.
+	 *
+	 * If the property is missing, just disable LVDS, and print a
+	 * warning.
+	 */
+	tcon->lvds_rst = devm_reset_control_get_optional(dev, "lvds");
+	if (IS_ERR(tcon->lvds_rst)) {
+		dev_err(dev, "Couldn't get our reset line\n");
+		return PTR_ERR(tcon->lvds_rst);
+	} else if (tcon->lvds_rst) {
+		has_lvds = true;
+		reset_control_reset(tcon->lvds_rst);
+	} else {
+		has_lvds = false;
+		dev_warn(dev,
+			 "Missing LVDS reset property, you should consider upgrading your DT\n");
+	}
+
 	ret = sun4i_tcon_init_clocks(dev, tcon);
 	if (ret) {
 		dev_err(dev, "Couldn't init our TCON clocks\n");
@@ -729,7 +909,18 @@  static int sun4i_tcon_bind(struct device *dev, struct device *master,
 		goto err_free_clocks;
 	}
 
-	ret = sun4i_rgb_init(drm, tcon);
+	/*
+	 * If we have an LVDS panel connected to the TCON, we should
+	 * just probe the LVDS connector. Otherwise, just probe RGB as
+	 * we used to.
+	 */
+	remote = of_graph_get_remote_node(dev->of_node, 1, 0);
+	if (has_lvds && of_device_is_compatible(remote, "panel-lvds"))
+		ret = sun4i_lvds_init(drm, tcon);
+	else
+		ret = sun4i_rgb_init(drm, tcon);
+	of_node_put(remote);
+
 	if (ret < 0)
 		goto err_free_clocks;
 
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
index 4141fbd97ddf..382689e5396e 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
@@ -70,7 +70,21 @@ 
 #define SUN4I_TCON0_TTL2_REG			0x78
 #define SUN4I_TCON0_TTL3_REG			0x7c
 #define SUN4I_TCON0_TTL4_REG			0x80
+
 #define SUN4I_TCON0_LVDS_IF_REG			0x84
+#define SUN4I_TCON0_LVDS_IF_EN				BIT(31)
+#define SUN4I_TCON0_LVDS_IF_BITWIDTH_MASK		BIT(26)
+#define SUN4I_TCON0_LVDS_IF_BITWIDTH_18BITS		(1 << 26)
+#define SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS		(0 << 26)
+#define SUN4I_TCON0_LVDS_IF_CLK_SEL_MASK		BIT(20)
+#define SUN4I_TCON0_LVDS_IF_CLK_SEL_TCON0		(1 << 20)
+#define SUN4I_TCON0_LVDS_IF_CLK_POL_MASK		BIT(4)
+#define SUN4I_TCON0_LVDS_IF_CLK_POL_NORMAL		(1 << 4)
+#define SUN4I_TCON0_LVDS_IF_CLK_POL_INV			(0 << 4)
+#define SUN4I_TCON0_LVDS_IF_DATA_POL_MASK		GENMASK(3, 0)
+#define SUN4I_TCON0_LVDS_IF_DATA_POL_NORMAL		(0xf)
+#define SUN4I_TCON0_LVDS_IF_DATA_POL_INV		(0)
+
 #define SUN4I_TCON0_IO_POL_REG			0x88
 #define SUN4I_TCON0_IO_POL_DCLK_PHASE(phase)		((phase & 3) << 28)
 #define SUN4I_TCON0_IO_POL_HSYNC_POSITIVE		BIT(25)
@@ -131,6 +145,16 @@ 
 #define SUN4I_TCON_CEU_RANGE_G_REG		0x144
 #define SUN4I_TCON_CEU_RANGE_B_REG		0x148
 #define SUN4I_TCON_MUX_CTRL_REG			0x200
+
+#define SUN4I_TCON0_LVDS_ANA0_REG		0x220
+#define SUN4I_TCON0_LVDS_ANA0_EN_MB			BIT(31)
+#define SUN4I_TCON0_LVDS_ANA0_EN_LDO			BIT(30)
+#define SUN4I_TCON0_LVDS_ANA0_EN_DRVC			BIT(24)
+#define SUN4I_TCON0_LVDS_ANA0_EN_DRVD(x)		(((x) & 0xf) << 20)
+#define SUN4I_TCON0_LVDS_ANA0_C(x)			(((x) & 3) << 17)
+#define SUN4I_TCON0_LVDS_ANA0_V(x)			(((x) & 3) << 8)
+#define SUN4I_TCON0_LVDS_ANA0_PD(x)			(((x) & 3) << 4)
+
 #define SUN4I_TCON1_FILL_CTL_REG		0x300
 #define SUN4I_TCON1_FILL_BEG0_REG		0x304
 #define SUN4I_TCON1_FILL_END0_REG		0x308
@@ -174,6 +198,7 @@  struct sun4i_tcon {
 
 	/* Reset control */
 	struct reset_control		*lcd_rst;
+	struct reset_control		*lvds_rst;
 
 	struct drm_panel		*panel;