HID: add compat support
Add compat option to hid code to allow loading of all modules on
systems which don't allow autoloading because of old userspace.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index cc8093c..4d2566a 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -287,6 +287,13 @@
---------------------------
+What: remove HID compat support
+When: 2.6.29
+Why: needed only as a temporary solution until distros fix themselves up
+Who: Jiri Slaby <jirislaby@gmail.com>
+
+---------------------------
+
What: /sys/o2cb symlink
When: January 2010
Why: /sys/fs/o2cb is the proper location for this information - /sys/o2cb
diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 41283ff..d9d1a56 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -70,6 +70,18 @@
menu "Special HID drivers"
depends on HID
+config HID_COMPAT
+ bool "Load all HID drivers on hid core load"
+ default y
+ ---help---
+ Compatible option for older userspace. If you have system without udev
+ support of module loading through aliases and also old
+ module-init-tools which can't handle hid bus, choose Y here. Otherwise
+ say N. If you say N and your userspace is old enough, the only
+ functionality you loose is modules autoloading.
+
+ If unsure, say Y.
+
config HID_APPLE
tristate "Apple"
default m
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index 4a14821..8e053ec 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -8,6 +8,10 @@
hid-$(CONFIG_HID_DEBUG) += hid-debug.o
hid-$(CONFIG_HIDRAW) += hidraw.o
+ifdef CONFIG_HID_COMPAT
+obj-m += hid-dummy.o
+endif
+
obj-$(CONFIG_HID_APPLE) += hid-apple.o
obj-$(CONFIG_HID_LOGITECH) += hid-logitech.o
diff --git a/drivers/hid/hid-apple.c b/drivers/hid/hid-apple.c
index 5642e2c..2a68661 100644
--- a/drivers/hid/hid-apple.c
+++ b/drivers/hid/hid-apple.c
@@ -477,3 +477,5 @@
module_init(apple_init);
module_exit(apple_exit);
MODULE_LICENSE("GPL");
+
+HID_COMPAT_LOAD_DRIVER(apple);
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 8e3c264..397e1b2 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1532,6 +1532,14 @@
}
EXPORT_SYMBOL_GPL(hid_unregister_driver);
+#ifdef CONFIG_HID_COMPAT
+static void hid_compat_load(struct work_struct *ws)
+{
+ request_module("hid-dummy");
+}
+static DECLARE_WORK(hid_compat_work, hid_compat_load);
+#endif
+
static int __init hid_init(void)
{
int ret;
@@ -1546,6 +1554,10 @@
if (ret)
goto err_bus;
+#ifdef CONFIG_HID_COMPAT
+ schedule_work(&hid_compat_work);
+#endif
+
return 0;
err_bus:
bus_unregister(&hid_bus_type);
diff --git a/drivers/hid/hid-dummy.c b/drivers/hid/hid-dummy.c
new file mode 100644
index 0000000..b76c44e
--- /dev/null
+++ b/drivers/hid/hid-dummy.c
@@ -0,0 +1,18 @@
+#include <linux/autoconf.h>
+#include <linux/module.h>
+#include <linux/hid.h>
+
+static int __init hid_dummy_init(void)
+{
+#ifdef CONFIG_HID_APPLE_MODULE
+ HID_COMPAT_CALL_DRIVER(apple);
+#endif
+#ifdef CONFIG_HID_LOGITECH_MODULE
+ HID_COMPAT_CALL_DRIVER(logitech);
+#endif
+
+ return -EIO;
+}
+module_init(hid_dummy_init);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/hid/hid-logitech.c b/drivers/hid/hid-logitech.c
index 395e42f..b2aaebe 100644
--- a/drivers/hid/hid-logitech.c
+++ b/drivers/hid/hid-logitech.c
@@ -310,3 +310,5 @@
module_init(lg_init);
module_exit(lg_exit);
MODULE_LICENSE("GPL");
+
+HID_COMPAT_LOAD_DRIVER(logitech);
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 75cc153..60e44e6b 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -790,10 +790,23 @@
return 0;
}
#define dbg_hid_line dbg_hid
-#endif
+#endif /* HID_DEBUG */
#define err_hid(format, arg...) printk(KERN_ERR "%s: " format "\n" , \
__FILE__ , ## arg)
-#endif
+#endif /* HID_FF */
+
+#ifdef CONFIG_HID_COMPAT
+#define HID_COMPAT_LOAD_DRIVER(name) \
+void hid_compat_##name(void) { } \
+EXPORT_SYMBOL(hid_compat_##name)
+#else
+#define HID_COMPAT_LOAD_DRIVER(name)
+#endif /* HID_COMPAT */
+#define HID_COMPAT_CALL_DRIVER(name) do { \
+ extern void hid_compat_##name(void); \
+ hid_compat_##name(); \
+} while (0)
+
#endif