[PATCH v2 1/3] staging: vc04_services: Support module autoloading using MODULE_DEVICE_TABLE
Umang Jain
umang.jain at ideasonboard.com
Tue Oct 17 22:42:12 PDT 2023
VC04 has now a independent bus vchiq_bus to register its devices.
However, the module auto-loading for bcm2835-audio and bcm2835-camera
currently happens through MODULE_ALIAS() macro specified explicitly.
The correct way to auto-load a module, is when the alias is picked
out from MODULE_DEVICE_TABLE(). In order to get there, we need to
introduce vchiq_device_id and add relevant entries in file2alias.c
infrastructure so that aliases can be generated. This patch targets
adding vchiq_bus_device_id and do_vchiq_bus_entry, in order to
generate those alias using the /script/mod/file2alias.c.
Going forward the MODULE_ALIAS() from bcm2835-camera and bcm2835-audio
will be dropped, in favour of MODULE_DEVICE_TABLE being used there.
The alias format for vchiq_bus devices will be "vchiq_bus:<dev_name>".
Adjust the vchiq_bus_uevent() to reflect that.
Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
---
.../vc04_services/interface/vchiq_arm/vchiq_bus.c | 2 +-
.../vc04_services/interface/vchiq_arm/vchiq_bus.h | 3 +++
include/linux/mod_devicetable.h | 4 ++++
scripts/mod/devicetable-offsets.c | 3 +++
scripts/mod/file2alias.c | 9 +++++++++
5 files changed, 20 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_bus.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_bus.c
index 4ac3491efe45..b4915bd76387 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_bus.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_bus.c
@@ -26,7 +26,7 @@ static int vchiq_bus_uevent(const struct device *dev, struct kobj_uevent_env *en
{
const struct vchiq_device *device = container_of_const(dev, struct vchiq_device, dev);
- return add_uevent_var(env, "MODALIAS=%s", dev_name(&device->dev));
+ return add_uevent_var(env, "MODALIAS=vchiq_bus:%s", dev_name(&device->dev));
}
static int vchiq_bus_probe(struct device *dev)
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_bus.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_bus.h
index 7eaaf9a91cda..6e1fbee4b078 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_bus.h
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_bus.h
@@ -7,6 +7,7 @@
#define _VCHIQ_DEVICE_H
#include <linux/device.h>
+#include <linux/mod_devicetable.h>
struct vchiq_device {
struct device dev;
@@ -18,6 +19,8 @@ struct vchiq_driver {
int (*resume)(struct vchiq_device *device);
int (*suspend)(struct vchiq_device *device,
pm_message_t state);
+
+ const struct vchiq_bus_device_id *id_table;
struct device_driver driver;
};
diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index b0678b093cb2..f01e175f7f3d 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -946,4 +946,8 @@ struct cdx_device_id {
__u32 override_only;
};
+struct vchiq_bus_device_id {
+ char name[32];
+};
+
#endif /* LINUX_MOD_DEVICETABLE_H */
diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c
index abe65f8968dd..c9a02d2c4f9e 100644
--- a/scripts/mod/devicetable-offsets.c
+++ b/scripts/mod/devicetable-offsets.c
@@ -267,5 +267,8 @@ int main(void)
DEVID_FIELD(cdx_device_id, device);
DEVID_FIELD(cdx_device_id, override_only);
+ DEVID(vchiq_bus_device_id);
+ DEVID_FIELD(vchiq_bus_device_id, name);
+
return 0;
}
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 38120f932b0d..6908dc70b649 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1478,6 +1478,14 @@ static int do_cdx_entry(const char *filename, void *symval,
return 1;
}
+static int do_vchiq_bus_entry(const char *filename, void *symval, char *alias)
+{
+ DEF_FIELD_ADDR(symval, vchiq_bus_device_id, name);
+ sprintf(alias, "vchiq_bus:%s", *name);
+
+ return 1;
+}
+
/* Does namelen bytes of name exactly match the symbol? */
static bool sym_is(const char *name, unsigned namelen, const char *symbol)
{
@@ -1558,6 +1566,7 @@ static const struct devtable devtable[] = {
{"dfl", SIZE_dfl_device_id, do_dfl_entry},
{"ishtp", SIZE_ishtp_device_id, do_ishtp_entry},
{"cdx", SIZE_cdx_device_id, do_cdx_entry},
+ {"vchiq_bus", SIZE_vchiq_bus_device_id, do_vchiq_bus_entry},
};
/* Create MODULE_ALIAS() statements.
--
2.40.1
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