[PATCH v2 2/5] cdx: use generic driver_override infrastructure

Danilo Krummrich
2026-05-05T13:39:56Z

Fixes: 2959ab247061 ("cdx: add the cdx bus driver")
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
---
drivers/cdx/cdx.c | 40 +++++--------------------------------
include/linux/cdx/cdx_bus.h | 4 ----
2 files changed, 5 insertions(+), 39 deletions(-)

diff --git a/drivers/cdx/cdx.c b/drivers/cdx/cdx.c
index 9196dc50a48d..d3d230247262 100644
--- a/drivers/cdx/cdx.c
+++ b/drivers/cdx/cdx.c
@@ -156,8 +156,6 @@ static int cdx_unregister_device(struct device *dev,
} else {
cdx_destroy_res_attr(cdx_dev, MAX_CDX_DEV_RESOURCES);
debugfs_remove_recursive(cdx_dev->debugfs_dir);
- kfree(cdx_dev->driver_override);
- cdx_dev->driver_override = NULL;
}

/*
@@ -268,6 +266,7 @@ static int cdx_bus_match(struct device *dev, const struct device_driver *drv)
const struct cdx_driver *cdx_drv = to_cdx_driver(drv);
const struct cdx_device_id *found_id = NULL;
const struct cdx_device_id *ids;
+ int ret;

if (cdx_dev->is_bus)
return false;
@@ -275,7 +274,8 @@ static int cdx_bus_match(struct device *dev, const struct device_driver *drv)
ids = cdx_drv->match_id_table;

/* When driver_override is set, only bind to the matching driver */
- if (cdx_dev->driver_override && strcmp(cdx_dev->driver_override, drv->name))
+ ret = device_match_driver_override(dev, drv);
+ if (ret == 0)
return false;

found_id = cdx_match_id(ids, cdx_dev);
@@ -289,7 +289,7 @@ static int cdx_bus_match(struct device *dev, const struct device_driver *drv)
*/
if (!found_id->override_only)
return true;
- if (cdx_dev->driver_override)
+ if (ret > 0)
return true;

ids = found_id + 1;
@@ -453,36 +453,6 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
}
static DEVICE_ATTR_RO(modalias);

-static ssize_t driver_override_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
-{
- struct cdx_device *cdx_dev = to_cdx_device(dev);
- int ret;
-
- if (WARN_ON(dev->bus != &cdx_bus_type))
- return -EINVAL;
-
- ret = driver_set_override(dev, &cdx_dev->driver_override, buf, count);
- if (ret)
- return ret;
-
- return count;
-}
-
-static ssize_t driver_override_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct cdx_device *cdx_dev = to_cdx_device(dev);
- ssize_t len;
-
- device_lock(dev);
- len = sysfs_emit(buf, "%s\n", cdx_dev->driver_override);
- device_unlock(dev);
- return len;
-}
-static DEVICE_ATTR_RW(driver_override);
-
static ssize_t enable_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
@@ -552,7 +522,6 @@ static struct attribute *cdx_dev_attrs[] = {
&dev_attr_class.attr,
&dev_attr_revision.attr,
&dev_attr_modalias.attr,
- &dev_attr_driver_override.attr,
NULL,
};

@@ -646,6 +615,7 @@ ATTRIBUTE_GROUPS(cdx_bus);

const struct bus_type cdx_bus_type = {
.name = "cdx",
+ .driver_override = true,
.match = cdx_bus_match,
.probe = cdx_probe,
.remove = cdx_remove,
diff --git a/include/linux/cdx/cdx_bus.h b/include/linux/cdx/cdx_bus.h
index b1ba97f6c9ad..f54770f110bc 100644
--- a/include/linux/cdx/cdx_bus.h
+++ b/include/linux/cdx/cdx_bus.h
@@ -137,9 +137,6 @@ struct cdx_controller {
* @enabled: is this bus enabled
* @msi_dev_id: MSI Device ID associated with CDX device
* @num_msi: Number of MSI's supported by the device
- * @driver_override: driver name to force a match; do not set directly,
- * because core frees it; use driver_set_override() to
- * set or clear it.
* @irqchip_lock: lock to synchronize irq/msi configuration
* @msi_write_pending: MSI write pending for this device
*/
@@ -165,7 +162,6 @@ struct cdx_device {
bool enabled;
u32 msi_dev_id;
u32 num_msi;
- const char *driver_override;
struct mutex irqchip_lock;
bool msi_write_pending;
};
--
2.54.0