[PATCH 3/3] mic: cosm: module autoprobing support for cosm driver

From: Sherry Sun
Date: Fri Sep 25 2020 - 03:33:26 EST


Add uevent callback for cosm_bus and add cosm_device_id for cosm driver
which is needed for MODULE_DEVICE_TABLE. Also adding struct
cosm_device_id in devicetable-offsets.c and the cosm entry point in
file2alias.c.

Cosm driver will be autoloaded when cosm device appears.

Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx>
---
drivers/misc/mic/bus/cosm_bus.c | 8 ++++++++
drivers/misc/mic/cosm/cosm_main.c | 7 +++++++
include/linux/mod_devicetable.h | 8 ++++++++
scripts/mod/devicetable-offsets.c | 3 +++
scripts/mod/file2alias.c | 11 +++++++++++
5 files changed, 37 insertions(+)

diff --git a/drivers/misc/mic/bus/cosm_bus.c b/drivers/misc/mic/bus/cosm_bus.c
index 5f2141c71738..736e27bbc9f9 100644
--- a/drivers/misc/mic/bus/cosm_bus.c
+++ b/drivers/misc/mic/bus/cosm_bus.c
@@ -14,6 +14,13 @@
/* Unique numbering for cosm devices. */
static DEFINE_IDA(cosm_index_ida);

+static int cosm_uevent(struct device *d, struct kobj_uevent_env *env)
+{
+ struct cosm_device *dev = dev_to_cosm(d);
+
+ return add_uevent_var(env, "MODALIAS=cosm:cosm-dev%u", dev->index);
+}
+
static int cosm_dev_probe(struct device *d)
{
struct cosm_device *dev = dev_to_cosm(d);
@@ -33,6 +40,7 @@ static int cosm_dev_remove(struct device *d)

static struct bus_type cosm_bus = {
.name = "cosm_bus",
+ .uevent = cosm_uevent,
.probe = cosm_dev_probe,
.remove = cosm_dev_remove,
};
diff --git a/drivers/misc/mic/cosm/cosm_main.c b/drivers/misc/mic/cosm/cosm_main.c
index ebb0eac43754..627e7d5f3a83 100644
--- a/drivers/misc/mic/cosm/cosm_main.c
+++ b/drivers/misc/mic/cosm/cosm_main.c
@@ -12,6 +12,7 @@
#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/cred.h>
+#include <linux/mod_devicetable.h>
#include "cosm_main.h"

static const char cosm_driver_name[] = "mic";
@@ -323,6 +324,12 @@ static int cosm_suspend(struct device *dev)
return 0;
}

+static struct cosm_device_id __maybe_unused cosm_driver_id_table[] = {
+ { .name = "cosm-dev*" },
+ { },
+};
+MODULE_DEVICE_TABLE(cosm, cosm_driver_id_table);
+
static const struct dev_pm_ops cosm_pm_ops = {
.suspend = cosm_suspend,
.freeze = cosm_suspend
diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 736cdc236cf9..ea6cdfe1a3a3 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -845,4 +845,12 @@ struct vop_device_id {
};
#define VOP_DEV_ANY_ID 0xffffffff

+/* cosm */
+#define COSM_NAME_SIZE 32
+#define COSM_MODULE_PREFIX "cosm:"
+
+struct cosm_device_id {
+ char name[COSM_NAME_SIZE];
+};
+
#endif /* LINUX_MOD_DEVICETABLE_H */
diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c
index 393acaa5302a..499a2832878d 100644
--- a/scripts/mod/devicetable-offsets.c
+++ b/scripts/mod/devicetable-offsets.c
@@ -247,5 +247,8 @@ int main(void)
DEVID_FIELD(vop_device_id, device);
DEVID_FIELD(vop_device_id, vendor);

+ DEVID(cosm_device_id);
+ DEVID_FIELD(cosm_device_id, name);
+
return 0;
}
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 8063b778eedf..f7c80e4da137 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1383,6 +1383,16 @@ static int do_vop_entry(const char *filename, void *symval,
return 1;
}

+/* Looks like: cosm:S */
+static int do_cosm_entry(const char *filename, void *symval,
+ char *alias)
+{
+ DEF_FIELD_ADDR(symval, cosm_device_id, name);
+ sprintf(alias, COSM_MODULE_PREFIX "%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)
{
@@ -1458,6 +1468,7 @@ static const struct devtable devtable[] = {
{"wmi", SIZE_wmi_device_id, do_wmi_entry},
{"mhi", SIZE_mhi_device_id, do_mhi_entry},
{"vop", SIZE_vop_device_id, do_vop_entry},
+ {"cosm", SIZE_cosm_device_id, do_cosm_entry},
};

/* Create MODULE_ALIAS() statements.
--
2.17.1