Fix rpi touchscreen support on master

We seem to miss a few bits that changed between kernel 4.9 and kernel 4.14
regarding the 7'' touchscreen.

One addition is the rpi-backlight.dtbo which we also need to use in our create-combined-dtb
recipe for CI use.

We also seem to require https://github.com/raspberrypi/linux/pull/2693#issue-217750943 .

Thanks to Scott Murray for the help digging through this.

v2 and v3: add devicetree changes
v4 and v5: fix name of dtbo
v6: move append to machine include - we need it as a global var
v7: add to config.txt for sdcard boot case

Bug-AGL: SPEC-2465

Change-Id: I2bb3cd974b74a790292e1f36ffdca034928e0bca
Signed-off-by: Jan-Simon Möller <jsmoeller@linuxfoundation.org>

1 files changed, 102 insertions, 0 deletions

diff --git a/meta-agl-bsp/meta-raspberrypi/recipes-kernel/linux/linux-raspberrypi/dsi/0002-drm-vc4-Make-DSI-call-into-the-bridge-after-the-DSI-.patch b/meta-agl-bsp/meta-raspberrypi/recipes-kernel/linux/linux-raspberrypi/dsi/0002-drm-vc4-Make-DSI-call-into-the-bridge-after-the-DSI-.patch
new file mode 100644
index 000000000..13d821418
--- /dev/null
+++ b/meta-agl-bsp/meta-raspberrypi/recipes-kernel/linux/linux-raspberrypi/dsi/0002-drm-vc4-Make-DSI-call-into-the-bridge-after-the-DSI-.patch
@@ -0,0 +1,102 @@
+From ab06860f2361a3750ec3a62347e0fdd7873cb30d Mon Sep 17 00:00:00 2001
+From: Kevin Quigley <kevin@kquigley.co.uk>
+Date: Mon, 24 Sep 2018 18:07:40 +0000
+Subject: [PATCH 2/4] drm/vc4: Make DSI call into the bridge after the DSI link
+ is enabled. bring this patch https://patchwork.kernel.org/patch/10480937/ to
+ Linux rpi-4.14.y
+
+This allows panels or bridges that need to send DSI commands during
+pre_enable() to successfully send them.  We delay DISP0 (aka the
+actual display) enabling until after pre_enable so that pixels aren't
+streaming before then.
+
+v2: Just clear out the encoder->bridge value to disable the midlayer
+    calls (idea by Andrzej Hajda).
+---
+ drivers/gpu/drm/vc4/vc4_dsi.c | 48 ++++++++++++++++++++++++-----------
+ 1 file changed, 33 insertions(+), 15 deletions(-)
+
+diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c
+index a3f416cbd1d6..3fa2db18d70f 100644
+--- a/drivers/gpu/drm/vc4/vc4_dsi.c
++++ b/drivers/gpu/drm/vc4/vc4_dsi.c
+@@ -814,7 +814,9 @@ static void vc4_dsi_encoder_disable(struct drm_encoder *encoder)
+ 	struct vc4_dsi *dsi = vc4_encoder->dsi;
+ 	struct device *dev = &dsi->pdev->dev;
+ 
++	drm_bridge_disable(dsi->bridge);
+ 	vc4_dsi_ulps(dsi, true);
++	drm_bridge_post_disable(dsi->bridge);
+ 
+ 	clk_disable_unprepare(dsi->pll_phy_clock);
+ 	clk_disable_unprepare(dsi->escape_clock);
+@@ -1089,21 +1091,6 @@ static void vc4_dsi_encoder_enable(struct drm_encoder *encoder)
+ 	/* Display reset sequence timeout */
+ 	DSI_PORT_WRITE(PR_TO_CNT, 100000);
+ 
+-	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
+-		DSI_PORT_WRITE(DISP0_CTRL,
+-			       VC4_SET_FIELD(dsi->divider,
+-					     DSI_DISP0_PIX_CLK_DIV) |
+-			       VC4_SET_FIELD(dsi->format, DSI_DISP0_PFORMAT) |
+-			       VC4_SET_FIELD(DSI_DISP0_LP_STOP_PERFRAME,
+-					     DSI_DISP0_LP_STOP_CTRL) |
+-			       DSI_DISP0_ST_END |
+-			       DSI_DISP0_ENABLE);
+-	} else {
+-		DSI_PORT_WRITE(DISP0_CTRL,
+-			       DSI_DISP0_COMMAND_MODE |
+-			       DSI_DISP0_ENABLE);
+-	}
+-
+ 	/* Set up DISP1 for transferring long command payloads through
+ 	 * the pixfifo.
+ 	 */
+@@ -1128,6 +1115,25 @@ static void vc4_dsi_encoder_enable(struct drm_encoder *encoder)
+ 
+ 	vc4_dsi_ulps(dsi, false);
+ 
++	drm_bridge_pre_enable(dsi->bridge);
++
++	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
++		DSI_PORT_WRITE(DISP0_CTRL,
++			       VC4_SET_FIELD(dsi->divider,
++					     DSI_DISP0_PIX_CLK_DIV) |
++			       VC4_SET_FIELD(dsi->format, DSI_DISP0_PFORMAT) |
++			       VC4_SET_FIELD(DSI_DISP0_LP_STOP_PERFRAME,
++					     DSI_DISP0_LP_STOP_CTRL) |
++			       DSI_DISP0_ST_END |
++			       DSI_DISP0_ENABLE);
++	} else {
++		DSI_PORT_WRITE(DISP0_CTRL,
++			       DSI_DISP0_COMMAND_MODE |
++			       DSI_DISP0_ENABLE);
++	}
++
++	drm_bridge_enable(dsi->bridge);
++
+ 	if (debug_dump_regs) {
+ 		DRM_INFO("DSI regs after:\n");
+ 		vc4_dsi_dump_regs(dsi);
+@@ -1656,6 +1662,18 @@ static int vc4_dsi_bind(struct device *dev, struct device *master, void *data)
+ 
+ 	dev_set_drvdata(dev, dsi);
+ 
++	ret = drm_bridge_attach(dsi->encoder, dsi->bridge, NULL);
++	if (ret) {
++		dev_err(dev, "bridge attach failed: %d\n", ret);
++		return ret;
++	}
++	/* Disable the atomic helper calls into the bridge.  We
++	 * manually call the bridge pre_enable / enable / etc. calls
++	 * from our driver, since we need to sequence them within the
++	 * encoder's enable/disable paths.
++	 */
++	dsi->encoder->bridge = NULL;
++
+ 	pm_runtime_enable(dev);
+ 
+ 	return 0;
+-- 
+2.21.0
+