On Tue, Feb 24, 2026 at 12:39:03AM +0530, Ekansh Gupta wrote:
Introduce a basic UAPI for the QDA accelerator driver along with a DRM IOCTL handler to query DSP device identity. A new UAPI header include/uapi/drm/qda_accel.h defines DRM_QDA_QUERY, the corresponding DRM_IOCTL_QDA_QUERY command, and struct drm_qda_query, which contains a DSP name string.
On the kernel side, qda_ioctl_query() validates the per-file context, resolves the qda_dev instance from dev->dev_private, and copies the DSP name from qdev->dsp_name into the query structure. The new qda_ioctls[] table wires this IOCTL into the QDA DRM driver so userspace can call it through the standard DRM command interface.
This IOCTL provides a simple and stable way for userspace to discover which DSP a given QDA device node represents and serves as the first building block for a richer QDA UAPI in subsequent patches.
Signed-off-by: Ekansh Gupta ekansh.gupta@oss.qualcomm.com
drivers/accel/qda/Makefile | 1 + drivers/accel/qda/qda_drv.c | 9 +++++++++ drivers/accel/qda/qda_ioctl.c | 45 +++++++++++++++++++++++++++++++++++++++++ drivers/accel/qda/qda_ioctl.h | 26 ++++++++++++++++++++++++ include/uapi/drm/qda_accel.h | 47 +++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 128 insertions(+)
diff --git a/drivers/accel/qda/Makefile b/drivers/accel/qda/Makefile index 7e96ddc40a24..f547398e1a72 100644 --- a/drivers/accel/qda/Makefile +++ b/drivers/accel/qda/Makefile @@ -10,5 +10,6 @@ qda-y := \ qda_rpmsg.o \ qda_cb.o \ qda_memory_manager.o \
- qda_ioctl.o \
Keep the list sorted, please.
obj-$(CONFIG_DRM_ACCEL_QDA_COMPUTE_BUS) += qda_compute_bus.o diff --git a/drivers/accel/qda/qda_drv.c b/drivers/accel/qda/qda_drv.c index bf95fc782cf8..86758a9cd982 100644 --- a/drivers/accel/qda/qda_drv.c +++ b/drivers/accel/qda/qda_drv.c @@ -9,7 +9,10 @@ #include <drm/drm_file.h> #include <drm/drm_gem.h> #include <drm/drm_ioctl.h> +#include <drm/qda_accel.h>
#include "qda_drv.h" +#include "qda_ioctl.h" #include "qda_rpmsg.h" static struct qda_drm_priv *get_drm_priv_from_device(struct drm_device *dev) @@ -128,11 +131,17 @@ static void qda_postclose(struct drm_device *dev, struct drm_file *file) DEFINE_DRM_ACCEL_FOPS(qda_accel_fops); +static const struct drm_ioctl_desc qda_ioctls[] = {
- DRM_IOCTL_DEF_DRV(QDA_QUERY, qda_ioctl_query, 0),
+};
static struct drm_driver qda_drm_driver = { .driver_features = DRIVER_COMPUTE_ACCEL, .fops = &qda_accel_fops, .open = qda_open, .postclose = qda_postclose,
- .ioctls = qda_ioctls,
Please select one style. Either you indent all assignments or you don't.
- .num_ioctls = ARRAY_SIZE(qda_ioctls), .name = DRIVER_NAME, .desc = "Qualcomm DSP Accelerator Driver",
}; diff --git a/drivers/accel/qda/qda_ioctl.c b/drivers/accel/qda/qda_ioctl.c new file mode 100644 index 000000000000..9fa73ec2dfce --- /dev/null +++ b/drivers/accel/qda/qda_ioctl.c @@ -0,0 +1,45 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. +#include <drm/drm_ioctl.h> +#include <drm/drm_gem.h> +#include <drm/qda_accel.h> +#include "qda_drv.h" +#include "qda_ioctl.h"
+static int qda_validate_and_get_context(struct drm_device *dev, struct drm_file *file_priv,
struct qda_dev **qdev, struct qda_user **qda_user)+{
- struct qda_drm_priv *drm_priv = dev->dev_private;
- struct qda_file_priv *qda_file_priv;
- if (!drm_priv)
return -EINVAL;- *qdev = drm_priv->qdev;
- if (!*qdev)
return -EINVAL;
Can this actually happen or is it (un)wishful thinking?
- qda_file_priv = (struct qda_file_priv *)file_priv->driver_priv;
- if (!qda_file_priv || !qda_file_priv->qda_user)
return -EINVAL;
What are you protecting against?
- *qda_user = qda_file_priv->qda_user;
- return 0;
+}
+int qda_ioctl_query(struct drm_device *dev, void *data, struct drm_file *file_priv) +{
- struct qda_dev *qdev;
- struct qda_user *qda_user;
- struct drm_qda_query *args = data;
- int ret;
- ret = qda_validate_and_get_context(dev, file_priv, &qdev, &qda_user);
- if (ret)
return ret;- strscpy(args->dsp_name, qdev->dsp_name, sizeof(args->dsp_name));
- return 0;
+} diff --git a/drivers/accel/qda/qda_ioctl.h b/drivers/accel/qda/qda_ioctl.h new file mode 100644 index 000000000000..6bf3bcd28c0e --- /dev/null +++ b/drivers/accel/qda/qda_ioctl.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/*
- Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
- */
+#ifndef _QDA_IOCTL_H +#define _QDA_IOCTL_H
+#include <linux/types.h> +#include <linux/kernel.h> +#include <drm/drm_ioctl.h> +#include "qda_drv.h"
+/**
- qda_ioctl_query - Query DSP device information and capabilities
- @dev: DRM device structure
- @data: User-space data containing query parameters and results
- @file_priv: DRM file private data
- This IOCTL handler queries information about the DSP device.
- Return: 0 on success, negative error code on failure
- */
+int qda_ioctl_query(struct drm_device *dev, void *data, struct drm_file *file_priv);
+#endif /* _QDA_IOCTL_H */ diff --git a/include/uapi/drm/qda_accel.h b/include/uapi/drm/qda_accel.h new file mode 100644 index 000000000000..0aad791c4832 --- /dev/null +++ b/include/uapi/drm/qda_accel.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note */ +/*
- Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
- */
+#ifndef __QDA_ACCEL_H__ +#define __QDA_ACCEL_H__
+#include "drm.h"
+#if defined(__cplusplus) +extern "C" { +#endif
+/*
- QDA IOCTL command numbers
- These define the command numbers for QDA-specific IOCTLs.
- They are used with DRM_COMMAND_BASE to create the full IOCTL numbers.
- */
+#define DRM_QDA_QUERY 0x00 +/*
- QDA IOCTL definitions
- These macros define the actual IOCTL numbers used by userspace applications.
- They combine the command numbers with DRM_COMMAND_BASE and specify the
- data structure and direction (read/write) for each IOCTL.
- */
+#define DRM_IOCTL_QDA_QUERY DRM_IOR(DRM_COMMAND_BASE + DRM_QDA_QUERY, struct drm_qda_query)
+/**
- struct drm_qda_query - Device information query structure
- @dsp_name: Name of DSP (e.g., "adsp", "cdsp", "cdsp1", "gdsp0", "gdsp1")
- This structure is used with DRM_IOCTL_QDA_QUERY to query device type,
- allowing userspace to identify which DSP a device node represents. The
- kernel provides the DSP name directly as a null-terminated string.
- */
+struct drm_qda_query {
- __u8 dsp_name[16];
+};
+#if defined(__cplusplus) +} +#endif
+#endif /* __QDA_ACCEL_H__ */
-- 2.34.1