[WIP PATCH v2 09/11] atmel_lcdfb: add support for updated DT bindings

[Sam Ravnborg <sam@ravnborg.org>]

The updated bindings for the display node uses graph nodes to
identify the panel.

Update the driver to support the new binding:
- Add support for the video pipeline (vpl)
- Add guard-time to the chip info
- Move deprecated display support to own function

With this update there is support for specifying a backlight node
as part of the panel node.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
---
 drivers/video/atmel_lcdfb.c      |   6 ++
 drivers/video/atmel_lcdfb.h      |   4 +
 drivers/video/atmel_lcdfb_core.c | 125 +++++++++++++++++++++++++------
 3 files changed, 113 insertions(+), 22 deletions(-)

diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index 38b4b8df3..1087102c4 100644
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -231,26 +231,32 @@ static int atmel_lcdc_probe(struct device_d *dev)
 static struct atmel_lcdfb_config at91sam9261_config = {
 	.have_hozval		= true,
 	.have_intensity_bit	= true,
+	.guard_time		= 1,
 };
 
 static struct atmel_lcdfb_config at91sam9263_config = {
 	.have_intensity_bit	= true,
+	.guard_time		= 1,
 };
 
 static struct atmel_lcdfb_config at91sam9g10_config = {
 	.have_hozval		= true,
+	.guard_time		= 1,
 };
 
 static struct atmel_lcdfb_config at91sam9g45_config = {
 	.have_alt_pixclock	= true,
+	.guard_time		= 9,
 };
 
 static struct atmel_lcdfb_config at91sam9rl_config = {
 	.have_intensity_bit	= true,
+	.guard_time		= 1,
 };
 
 static struct atmel_lcdfb_config at32ap_config = {
 	.have_hozval		= true,
+	.guard_time		= 1,
 };
 
 static __maybe_unused struct of_device_id atmel_lcdfb_compatible[] = {
diff --git a/drivers/video/atmel_lcdfb.h b/drivers/video/atmel_lcdfb.h
index 110c71bdb..69a27cb23 100644
--- a/drivers/video/atmel_lcdfb.h
+++ b/drivers/video/atmel_lcdfb.h
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 
 #include <fb.h>
+#include <video/vpl.h>
 #include <video/atmel_lcdc.h>
 
 struct atmel_lcdfb_info;
@@ -9,6 +10,7 @@ struct atmel_lcdfb_config {
 	bool have_alt_pixclock;
 	bool have_hozval;
 	bool have_intensity_bit;
+	unsigned int guard_time;
 };
 
 struct atmel_lcdfb_devdata {
@@ -25,6 +27,8 @@ struct atmel_lcdfb_info {
 	struct fb_info		info;
 	void __iomem		*mmio;
 	struct device_d		*device;
+	int			id;
+	struct vpl		vpl;
 
 	unsigned int		guard_time;
 	unsigned int		smem_len;
diff --git a/drivers/video/atmel_lcdfb_core.c b/drivers/video/atmel_lcdfb_core.c
index 17f754b56..681b20a3d 100644
--- a/drivers/video/atmel_lcdfb_core.c
+++ b/drivers/video/atmel_lcdfb_core.c
@@ -13,6 +13,7 @@
 #include <linux/err.h>
 #include <linux/clk.h>
 #include <malloc.h>
+#include <of_graph.h>
 
 #include <mach/cpu.h>
 
@@ -30,10 +31,8 @@ static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
 	clk_disable(sinfo->lcdc_clk);
 }
 
-static void atmel_lcdc_power_controller(struct fb_info *fb_info, int on)
+static void atmel_lcdc_power_controller(struct atmel_lcdfb_info *sinfo, int on)
 {
-	struct atmel_lcdfb_info *sinfo = fb_info->priv;
-
 	if (sinfo->gpio_power_control < 0)
 		return;
 
@@ -48,7 +47,12 @@ static void atmel_lcdc_power_controller(struct fb_info *fb_info, int on)
  */
 static void atmel_lcdc_enable_controller(struct fb_info *fb_info)
 {
-	atmel_lcdc_power_controller(fb_info, 1);
+	struct atmel_lcdfb_info *sinfo = fb_info->priv;
+	struct fb_videomode *mode = fb_info->mode;
+
+	vpl_ioctl_prepare(&sinfo->vpl, sinfo->id, mode);
+	atmel_lcdc_power_controller(sinfo, 1);
+	vpl_ioctl_enable(&sinfo->vpl, sinfo->id);
 }
 
 /**
@@ -56,7 +60,11 @@ static void atmel_lcdc_enable_controller(struct fb_info *fb_info)
  */
 static void atmel_lcdc_disable_controller(struct fb_info *fb_info)
 {
-	atmel_lcdc_power_controller(fb_info, 0);
+	struct atmel_lcdfb_info *sinfo = fb_info->priv;
+
+	vpl_ioctl_disable(&sinfo->vpl, sinfo->id);
+	atmel_lcdc_power_controller(sinfo, 0);
+	vpl_ioctl_unprepare(&sinfo->vpl, sinfo->id);
 }
 
 
@@ -311,28 +319,14 @@ static int of_get_power_control(struct device_d *dev,
 	return power_control_init(dev, sinfo, gpio, active_low);
 }
 
-static int lcdfb_of_init(struct device_d *dev, struct atmel_lcdfb_info *sinfo)
+static int lcdfb_display_init(struct device_d *dev,
+			      struct atmel_lcdfb_info *sinfo,
+			      struct device_node *display)
 {
 	struct fb_info *info = &sinfo->info;
 	struct display_timings *modes;
-	struct device_node *display;
-	struct atmel_lcdfb_config *config;
 	int ret;
 
-	/* Driver data - optional */
-	ret = dev_get_drvdata(dev, (const void **)&config);
-	if (!ret) {
-		sinfo->have_hozval = config->have_hozval;
-		sinfo->have_intensity_bit = config->have_intensity_bit;
-		sinfo->have_alt_pixclock = config->have_alt_pixclock;
-	}
-
-	/* Required properties */
-	display = of_parse_phandle(dev->device_node, "display", 0);
-	if (!display) {
-		dev_err(dev, "no display phandle\n");
-		return -ENOENT;
-	}
 	ret = of_property_read_u32(display, "atmel,guard-time", &sinfo->guard_time);
 	if (ret < 0) {
 		dev_err(dev, "failed to get atmel,guard-time property\n");
@@ -373,9 +367,95 @@ static int lcdfb_of_init(struct device_d *dev, struct atmel_lcdfb_info *sinfo)
 		dev_err(dev, "failed to get power control gpio\n");
 		goto err;
 	}
+
 	return 0;
+
 err:
 	return ret;
+
+}
+
+static int lcdfb_of_init(struct device_d *dev, struct atmel_lcdfb_info *sinfo)
+{
+	struct fb_info *info = &sinfo->info;
+	struct atmel_lcdfb_config *config;
+	struct device_node *display;
+	struct device_node *np = NULL;
+	struct of_endpoint ep;
+	int ret;
+
+	/* Driver data - optional */
+	ret = dev_get_drvdata(dev, (const void **)&config);
+	if (!ret) {
+		sinfo->have_hozval = config->have_hozval;
+		sinfo->have_intensity_bit = config->have_intensity_bit;
+		sinfo->have_alt_pixclock = config->have_alt_pixclock;
+
+		/* The display node will override the guard time if present */
+		sinfo->guard_time = config->guard_time;
+	}
+
+	/* The display handle is deprecated but still supported */
+	display = of_parse_phandle(dev->device_node, "display", 0);
+	if (display) {
+		return lcdfb_display_init(dev, sinfo, display);
+	}
+
+	for_each_available_child_of_node(dev->device_node, np) {
+		if (!of_graph_port_is_available(np))
+			continue;
+
+		ret = of_graph_parse_endpoint(np, &ep);
+		if (ret) {
+			dev_err(dev, "failed to parse endpoint\n");
+			return ret;
+		}
+		sinfo->id = ep.id;
+		break;
+	}
+
+	dev_dbg(dev, "register vpl for %s\n", dev->device_node->full_name);
+	ret = vpl_register(&sinfo->vpl);
+	if (ret)
+		return ret;
+
+	/* Only TFT panels - STN is obsolete */
+	sinfo->lcdcon2 = ATMEL_LCDC_DISTYPE_TFT;
+
+	/* LCDD Polarity normal */
+	sinfo->lcdcon2 |= ATMEL_LCDC_INVVD_NORMAL;
+
+	/* Clock is always active */
+	sinfo->lcdcon2 |= ATMEL_LCDC_CLKMOD_ALWAYSACTIVE;
+
+	/* Memory layout */
+	sinfo->lcdcon2 |= ATMEL_LCDC_MEMOR_LITTLE;
+
+	sinfo->dmacon = ATMEL_LCDC_DMAEN;
+
+	/* TODO: Maybe obtain this from panel */
+	info->bits_per_pixel = 16;
+
+	ret = vpl_ioctl(&sinfo->vpl, sinfo->id, VPL_GET_VIDEOMODES, &info->modes);
+	if (ret) {
+		dev_dbg(dev, "failed to get modes: %s\n", strerror(-ret));
+		return ret;
+	}
+
+	/* Optional properties */
+	ret = of_get_wiring_mode(dev->device_node, sinfo);
+	if (ret < 0) {
+		dev_err(dev, "failed to get atmel,lcd-wiring-mode property\n");
+		return ret;
+	}
+
+	ret = of_get_power_control(dev, dev->device_node, sinfo);
+	if (ret < 0) {
+		dev_err(dev, "failed to get power control gpio\n");
+		return ret;
+	}
+
+	return 0;
 }
 
 static int lcdfb_pdata_init(struct device_d *dev, struct atmel_lcdfb_info *sinfo)
@@ -441,6 +521,7 @@ int atmel_lcdc_register(struct device_d *dev, struct atmel_lcdfb_devdata *data)
 	info = &sinfo->info;
 	info->priv = sinfo;
 	info->fbops = &atmel_lcdc_ops;
+	sinfo->vpl.node = dev->device_node;
 
 	if (dev->platform_data) {
 		ret = lcdfb_pdata_init(dev, sinfo);
-- 
2.34.1