From b8c5cec23d5c33b767a1cddebd4f8813a9563e3c Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Fri, 16 Feb 2007 17:33:36 +0100 Subject: Driver core: udev triggered device-<>driver binding We get two per-bus sysfs files: ls-l /sys/subsystem/usb drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers -rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe --w------- 1 root root 4096 2007-02-16 16:42 drivers_probe The flag "drivers_autoprobe" controls the behavior of the bus to bind devices by default, or just initialize the device and leave it alone. The command "drivers_probe" accepts a bus_id and the bus tries to bind a driver to this device. Systems who want to control the driver binding with udev, switch off the bus initiated probing: echo 0 > /sys/subsystem/usb/drivers_autoprobe echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe ... and initiate the probing with udev rules like: ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel" ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel" ... Custom driver binding can happen in earlier rules by something like: ACTION=="add", SUBSYSTEM=="usb", \ ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \ ATTR{subsystem/drivers//bind}="$kernel" This is intended to solve the modprobe.conf mess with "install-rules", custom bind/unbind-scripts and all the weird things people invented over the years. It should also provide the functionality "libusual" was supposed to do. With udev, one can just write a udev rule to drive all USB-disks at the third port of USB-hub by the "ub" driver, and everything else by usb-storage. One can also instruct udev to bind different wireless drivers to identical cards - just selected by the pcmcia slot-number, and whatever ... To use the mentioned rules, it needs udev version 106, to be able to write ATTR{}="$kernel" to sysfs files. Signed-off-by: Greg Kroah-Hartman --- include/linux/device.h | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-) (limited to 'include') diff --git a/include/linux/device.h b/include/linux/device.h index de0e73eae6b..9d54fe13eb2 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -34,9 +34,24 @@ struct device; struct device_driver; struct class; struct class_device; +struct bus_type; + +struct bus_attribute { + struct attribute attr; + ssize_t (*show)(struct bus_type *, char * buf); + ssize_t (*store)(struct bus_type *, const char * buf, size_t count); +}; + +#define BUS_ATTR(_name,_mode,_show,_store) \ +struct bus_attribute bus_attr_##_name = __ATTR(_name,_mode,_show,_store) + +extern int __must_check bus_create_file(struct bus_type *, + struct bus_attribute *); +extern void bus_remove_file(struct bus_type *, struct bus_attribute *); struct bus_type { const char * name; + struct module * owner; struct subsystem subsys; struct kset drivers; @@ -49,6 +64,8 @@ struct bus_type { struct bus_attribute * bus_attrs; struct device_attribute * dev_attrs; struct driver_attribute * drv_attrs; + struct bus_attribute drivers_autoprobe_attr; + struct bus_attribute drivers_probe_attr; int (*match)(struct device * dev, struct device_driver * drv); int (*uevent)(struct device *dev, char **envp, @@ -61,6 +78,8 @@ struct bus_type { int (*suspend_late)(struct device * dev, pm_message_t state); int (*resume_early)(struct device * dev); int (*resume)(struct device * dev); + + unsigned int drivers_autoprobe:1; }; extern int __must_check bus_register(struct bus_type * bus); @@ -102,21 +121,6 @@ extern int bus_unregister_notifier(struct bus_type *bus, #define BUS_NOTIFY_UNBIND_DRIVER 0x00000004 /* driver about to be unbound */ -/* sysfs interface for exporting bus attributes */ - -struct bus_attribute { - struct attribute attr; - ssize_t (*show)(struct bus_type *, char * buf); - ssize_t (*store)(struct bus_type *, const char * buf, size_t count); -}; - -#define BUS_ATTR(_name,_mode,_show,_store) \ -struct bus_attribute bus_attr_##_name = __ATTR(_name,_mode,_show,_store) - -extern int __must_check bus_create_file(struct bus_type *, - struct bus_attribute *); -extern void bus_remove_file(struct bus_type *, struct bus_attribute *); - struct device_driver { const char * name; struct bus_type * bus; -- cgit v1.2.3-70-g09d2