drm/sun4i: dw-hdmi: Make HDMI PHY into a platform device

On sunxi boards that use HDMI output, HDMI device probe keeps being
avoided indefinitely with these repeated messages in dmesg:

  platform 1ee0000.hdmi: probe deferral - supplier 1ef0000.hdmi-phy
    not ready

There's a fwnode_link being created with fw_devlink=on between hdmi
and hdmi-phy nodes, because both nodes have 'compatible' property set.

Fw_devlink code assumes that nodes that have compatible property
set will also have a device associated with them by some driver
eventually. This is not the case with the current sun8i-hdmi
driver.

This commit makes sun8i-hdmi-phy into a proper platform device
and fixes the display pipeline probe on sunxi boards that use HDMI.

More context: https://lkml.org/lkml/2021/5/16/203

Signed-off-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Ondrej Jirman <megous@megous.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210607085836.2827429-1-megous@megous.com

1 files changed, 36 insertions, 5 deletions

diff --git a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
index 9994edf67509..c9239708d398 100644
--- a/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
+++ b/drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c
@@ -5,6 +5,7 @@
 
 #include <linux/delay.h>
 #include <linux/of_address.h>
+#include <linux/of_platform.h>
 
 #include "sun8i_dw_hdmi.h"
 
@@ -597,10 +598,30 @@ static const struct of_device_id sun8i_hdmi_phy_of_table[] = {
 	{ /* sentinel */ }
 };
 
-int sun8i_hdmi_phy_probe(struct sun8i_dw_hdmi *hdmi, struct device_node *node)
+int sun8i_hdmi_phy_get(struct sun8i_dw_hdmi *hdmi, struct device_node *node)
+{
+	struct platform_device *pdev = of_find_device_by_node(node);
+	struct sun8i_hdmi_phy *phy;
+
+	if (!pdev)
+		return -EPROBE_DEFER;
+
+	phy = platform_get_drvdata(pdev);
+	if (!phy)
+		return -EPROBE_DEFER;
+
+	hdmi->phy = phy;
+
+	put_device(&pdev->dev);
+
+	return 0;
+}
+
+static int sun8i_hdmi_phy_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *match;
-	struct device *dev = hdmi->dev;
+	struct device *dev = &pdev->dev;
+	struct device_node *node = dev->of_node;
 	struct sun8i_hdmi_phy *phy;
 	struct resource res;
 	void __iomem *regs;
@@ -704,7 +725,7 @@ int sun8i_hdmi_phy_probe(struct sun8i_dw_hdmi *hdmi, struct device_node *node)
 		clk_prepare_enable(phy->clk_phy);
 	}
 
-	hdmi->phy = phy;
+	platform_set_drvdata(pdev, phy);
 
 	return 0;
 
@@ -728,9 +749,9 @@ err_put_clk_bus:
 	return ret;
 }
 
-void sun8i_hdmi_phy_remove(struct sun8i_dw_hdmi *hdmi)
+static int sun8i_hdmi_phy_remove(struct platform_device *pdev)
 {
-	struct sun8i_hdmi_phy *phy = hdmi->phy;
+	struct sun8i_hdmi_phy *phy = platform_get_drvdata(pdev);
 
 	clk_disable_unprepare(phy->clk_mod);
 	clk_disable_unprepare(phy->clk_bus);
@@ -744,4 +765,14 @@ void sun8i_hdmi_phy_remove(struct sun8i_dw_hdmi *hdmi)
 	clk_put(phy->clk_pll1);
 	clk_put(phy->clk_mod);
 	clk_put(phy->clk_bus);
+	return 0;
 }
+
+struct platform_driver sun8i_hdmi_phy_driver = {
+	.probe  = sun8i_hdmi_phy_probe,
+	.remove = sun8i_hdmi_phy_remove,
+	.driver = {
+		.name = "sun8i-hdmi-phy",
+		.of_match_table = sun8i_hdmi_phy_of_table,
+	},
+};