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

From: Maxime Ripard
Date: Tue Oct 17 2017 - 05:12:20 EST

The TCON supports the LVDS interface to output to a panel or a bridge.
Let's add support for it.

Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/sun4i/Makefile | 1 +-
drivers/gpu/drm/sun4i/sun4i_lvds.c | 183 ++++++++++++++++++++++++++++-
drivers/gpu/drm/sun4i/sun4i_lvds.h | 18 +++-
drivers/gpu/drm/sun4i/sun4i_tcon.c | 193 +++++++++++++++++++++++++++++-
drivers/gpu/drm/sun4i/sun4i_tcon.h | 25 ++++-
5 files changed, 419 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/drm/sun4i/sun4i_lvds.c
create mode 100644 drivers/gpu/drm/sun4i/sun4i_lvds.h

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@xxxxxxxxxxxxxxxxxx>
+ *
+ * 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@xxxxxxxxxxxxxxxxxx>
+ *
+ * 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;

--
git-series 0.9.1