From: Vamsee Vardhan Thummala <vthumm...@nvidia.com>
Add support to register host1x devices without requiring subdevices.
This ensures syncpoint functionality remains available even when engine
subdevices are not present.
Add softdep for tegra-drm to make userspace interface available
without module autoloading through device tree entries.
Signed-off-by: Vamsee Vardhan Thummala <vthumm...@nvidia.com>
[mperttu...@nvidia.com: some rewording]
Signed-off-by: Mikko Perttunen <mperttu...@nvidia.com>
---
drivers/gpu/host1x/bus.c | 12 ++++++++++++
drivers/gpu/host1x/dev.c | 1 +
2 files changed, 13 insertions(+)
diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
index
344cc9e741c1357420240467754fd151926b3bd5..723a80895cd43bde840adf8d26812e82d12385ab
100644
--- a/drivers/gpu/host1x/bus.c
+++ b/drivers/gpu/host1x/bus.c
@@ -471,6 +471,18 @@ static int host1x_device_add(struct host1x *host1x,
mutex_unlock(&clients_lock);
+ /*
+ * Add device even if there are no subdevs to ensure syncpoint
functionality
+ * is available regardless of whether any engine subdevices are present
+ */
+ if (list_empty(&device->subdevs)) {
+ err = device_add(&device->dev);
+ if (err < 0)
+ dev_err(&device->dev, "failed to add device: %d\n",
err);
+ else
+ device->registered = true;
+ }
+
return 0;
}
diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c
index
1f93e5e276c0835eac2f713ffcd60a9db8db2c21..e1a9246d35f4b7685dd828c53eaf3910a5ef739e
100644
--- a/drivers/gpu/host1x/dev.c
+++ b/drivers/gpu/host1x/dev.c
@@ -821,6 +821,7 @@ u64 host1x_get_dma_mask(struct host1x *host1x)
}
EXPORT_SYMBOL(host1x_get_dma_mask);
+MODULE_SOFTDEP("post: tegra-drm");
MODULE_AUTHOR("Thierry Reding <thierry.red...@avionic-design.de>");
MODULE_AUTHOR("Terje Bergstrom <tbergst...@nvidia.com>");
MODULE_DESCRIPTION("Host1x driver for Tegra products");
---
base-commit: 58ba80c4740212c29a1cf9b48f588e60a7612209
change-id: 20250708-host1x-allow-no-subdevs-f84bb7b48aa7
