From a4ff342afe2d05c6bb8f479b51c7365412763e9c Mon Sep 17 00:00:00 2001 From: Patrick Mochel Date: Mon, 9 Jun 2003 02:40:02 -0700 Subject: [driver model] Rewrite system device API System devices are special, and after two years of listening to Linus preach this, it finally sunk in enough to do something about. We don't need to regard them as real devices that reside on a peripheral bus and can be dynamically bound to drivers. If we discover, e.g. a CPU, we know by default that we have a driver for it, and we know damn well that we have a CPU. We still need to keep track of all the devices, and all the devices of a particular type. The kobject infrastructure allows us to do this, without the overhead of the regular model. A new subsystem is defined that registers as a child object of devices_subsys, giving us: /sys/devices/system/ struct sysdev_class { struct list_head drivers; /* Default operations for these types of devices */ int (*shutdown)(struct sys_device *); int (*suspend)(struct sys_device *, u32 state); int (*resume)(struct sys_device *); struct kset kset; }; Defines a type of system device. These are registered on startup, by e.g. drivers/base/cpu.c. The methods are default operations for devices of that type that may or may not be used. For things like the i8259 controller, these will be filled in, since it is registered by the same component that the device controls reside in. For things like CPUs, generic code will register the class, but other architecture-specific or otherwise configurable drivers may register auxillary drivers, that look like: struct sysdev_driver { struct list_head entry; int (*add)(struct sys_device *); int (*remove)(struct sys_device *); int (*shutdown)(struct sys_device *); int (*suspend)(struct sys_device *, u32 state); int (*resume)(struct sys_device *); }; Each auxillary driver gets called during each operation on a device of a particular class. Auxillary drivers may register with a NULL class parameter, in which case they will be added to a list of 'global drivers' that get called for each device of each class. Besides providing a decent of cleanup for system device drivers, this also allows: - Special handling of system devices during power transitions. We no longer have to worry about shutting down the PIC before we shut down any devices. We can shut down the system devices after we've shut down every other device. Ditto for suspend/resume cycles. Almost (if not) all PM actions for system devices happen with interrupts off, and require only one call, which makes that easier. But, we can also make sure we take care of these last during suspend and first during resume. - Easy expression of configurable device-specific interfaces. Namely cpufreq and mtrr. We don't have to worry about mispresentation in the driver model (like recent MTRR patches) or using a cumbersome interface ({device,class}_interface) that don't receive all the necessary calls. - Consolidation of userspace representation. No longer do we have /sys/devices/sys, /sys/bus/sys, and /sys/class/cpu, etc. We have only /sys/devices/system: # tree /sys/devices/system/ /sys/devices/system/ |-- cpu | `-- cpu0 |-- i8259 | `-- i82590 |-- lapic | `-- lapic0 |-- rtc | `-- rtc0 `-- timer `-- timer0 Each directory in 'system' is the class, and each directory under that is the instance of each device in that class. --- drivers/base/sys.c | 343 ++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 260 insertions(+), 83 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/sys.c b/drivers/base/sys.c index 5ae457170548..aa71e40a865e 100644 --- a/drivers/base/sys.c +++ b/drivers/base/sys.c @@ -12,7 +12,7 @@ * add themselves as children of the system bus. */ -#undef DEBUG +#define DEBUG #include #include @@ -22,130 +22,307 @@ #include #include -/* The default system device parent. */ -static struct device system_bus = { - .name = "System Bus", - .bus_id = "sys", -}; +extern struct subsystem devices_subsys; + +/* + * declare system_subsys + */ +decl_subsys(system,NULL,NULL); + +int sysdev_class_register(struct sysdev_class * cls) +{ + pr_debug("Registering sysdev class '%s'\n",cls->kset.kobj.name); + INIT_LIST_HEAD(&cls->drivers); + cls->kset.subsys = &system_subsys; + kset_set_kset_s(cls,system_subsys); + return kset_register(&cls->kset); +} + +void sysdev_class_unregister(struct sysdev_class * cls) +{ + pr_debug("Unregistering sysdev class '%s'\n",cls->kset.kobj.name); + kset_unregister(&cls->kset); +} + +EXPORT_SYMBOL(sysdev_class_register); +EXPORT_SYMBOL(sysdev_class_unregister); + + +static LIST_HEAD(global_drivers); /** - * sys_register_root - add a subordinate system root - * @root: new root - * - * This is for NUMA-like systems so they can accurately - * represent the topology of the entire system. - * As boards are discovered, a new struct sys_root should - * be allocated and registered. - * The discovery mechanism should initialize the id field - * of the struture, as well as much of the embedded device - * structure as possible, inlcuding the name, the bus_id - * and parent fields. + * sysdev_driver_register - Register auxillary driver + * @cls: Device class driver belongs to. + * @drv: Driver. * - * This simply calls device_register on the embedded device. - * On success, it will use the struct @root->sysdev - * device to create a pseudo-parent for system devices - * on that board. + * If @cls is valid, then @drv is inserted into @cls->drivers to be + * called on each operation on devices of that class. The refcount + * of @cls is incremented. + * Otherwise, @drv is inserted into global_drivers, and called for + * each device. + */ + +int sysdev_driver_register(struct sysdev_class * cls, + struct sysdev_driver * drv) +{ + down_write(&system_subsys.rwsem); + if (kset_get(&cls->kset)) + list_add_tail(&drv->entry,&cls->drivers); + else + list_add_tail(&drv->entry,&global_drivers); + up_write(&system_subsys.rwsem); + return 0; +} + + +/** + * sysdev_driver_unregister - Remove an auxillary driver. + * @cls: Class driver belongs to. + * @drv: Driver. + */ +void sysdev_driver_unregister(struct sysdev_class * cls, + struct sysdev_driver * drv) +{ + down_write(&system_subsys.rwsem); + list_del_init(&drv->entry); + if (cls) + kset_put(&cls->kset); + up_write(&system_subsys.rwsem); +} + + +/** + * sys_device_register - add a system device to the tree + * @sysdev: device in question * - * The platform code can then use @root to specifiy the - * controlling board when discovering and registering - * system devices. */ -int sys_register_root(struct sys_root * root) +int sys_device_register(struct sys_device * sysdev) { - int error = 0; + int error; + struct sysdev_class * cls = sysdev->cls; - if (!root) + if (!cls) return -EINVAL; - if (!root->dev.parent) - root->dev.parent = &system_bus; + /* Make sure the kset is set */ + sysdev->kobj.kset = &cls->kset; + + /* set the kobject name */ + snprintf(sysdev->kobj.name,KOBJ_NAME_LEN,"%s%d", + cls->kset.kobj.name,sysdev->id); + + pr_debug("Registering sys device '%s'\n",sysdev->kobj.name); - pr_debug("Registering system board %d\n",root->id); + /* Register the object */ + error = kobject_register(&sysdev->kobj); - error = device_register(&root->dev); if (!error) { - strlcpy(root->sysdev.bus_id,"sys",BUS_ID_SIZE); - strlcpy(root->sysdev.name,"System Bus",DEVICE_NAME_SIZE); - root->sysdev.parent = &root->dev; - error = device_register(&root->sysdev); - }; + struct sysdev_driver * drv; + + down_read(&system_subsys.rwsem); + /* Generic notification is implicit, because it's that + * code that should have called us. + */ + + /* Notify global drivers */ + list_for_each_entry(drv,&global_drivers,entry) { + if (drv->add) + drv->add(sysdev); + } + /* Notify class auxillary drivers */ + list_for_each_entry(drv,&cls->drivers,entry) { + if (drv->add) + drv->add(sysdev); + } + up_read(&system_subsys.rwsem); + } return error; } +void sys_device_unregister(struct sys_device * sysdev) +{ + struct sysdev_driver * drv; + + down_read(&system_subsys.rwsem); + list_for_each_entry(drv,&global_drivers,entry) { + if (drv->remove) + drv->remove(sysdev); + } + + list_for_each_entry(drv,&sysdev->cls->drivers,entry) { + if (drv->remove) + drv->remove(sysdev); + } + up_read(&system_subsys.rwsem); + + kobject_unregister(&sysdev->kobj); +} + + + /** - * sys_unregister_root - remove subordinate root from tree - * @root: subordinate root in question. + * sys_device_shutdown - Shut down all system devices. + * + * Loop over each class of system devices, and the devices in each + * of those classes. For each device, we call the shutdown method for + * each driver registered for the device - the globals, the auxillaries, + * and the class driver. * - * We only decrement the reference count on @root->sysdev - * and @root->dev. - * If both are 0, they will be cleaned up by the core. + * Note: The list is iterated in reverse order, so that we shut down + * child devices before we shut down thier parents. The list ordering + * is guaranteed by virtue of the fact that child devices are registered + * after their parents. */ -void sys_unregister_root(struct sys_root *root) + +void sys_device_shutdown(void) { - device_unregister(&root->sysdev); - device_unregister(&root->dev); + struct sysdev_class * cls; + + pr_debug("Shutting Down System Devices\n"); + + down_write(&system_subsys.rwsem); + list_for_each_entry_reverse(cls,&system_subsys.kset.list, + kset.kobj.entry) { + struct sys_device * sysdev; + + pr_debug("Shutting down type '%s':\n",cls->kset.kobj.name); + + list_for_each_entry(sysdev,&cls->kset.list,kobj.entry) { + struct sysdev_driver * drv; + pr_debug(" %s\n",sysdev->kobj.name); + + /* Call global drivers first. */ + list_for_each_entry(drv,&global_drivers,entry) { + if (drv->shutdown) + drv->shutdown(sysdev); + } + + /* Call auxillary drivers next. */ + list_for_each_entry(drv,&cls->drivers,entry) { + if (drv->shutdown) + drv->shutdown(sysdev); + } + + /* Now call the generic one */ + if (cls->shutdown) + cls->shutdown(sysdev); + } + } + up_write(&system_subsys.rwsem); } + /** - * sys_device_register - add a system device to the tree - * @sysdev: device in question - * - * The hardest part about this is getting the ancestry right. - * If the device has a parent - super! We do nothing. - * If the device doesn't, but @dev->root is set, then we're - * dealing with a NUMA like architecture where each root - * has a system pseudo-bus to foster the device. - * If not, then we fallback to system_bus (at the top of - * this file). + * sys_device_suspend - Suspend all system devices. + * @state: Power state to enter. * - * One way or another, we call device_register() on it and - * are done. + * We perform an almost identical operation as sys_device_shutdown() + * above, though calling ->suspend() instead. * - * The caller is also responsible for initializing the bus_id - * and name fields of @sysdev->dev. + * Note: Interrupts are disabled when called, so we can't sleep when + * trying to get the subsystem's rwsem. If that happens, print a nasty + * warning and return an error. */ -int sys_device_register(struct sys_device * sysdev) + +int sys_device_suspend(u32 state) { - if (!sysdev) - return -EINVAL; + struct sysdev_class * cls; - if (!sysdev->dev.parent) { - if (sysdev->root) - sysdev->dev.parent = &sysdev->root->sysdev; - else - sysdev->dev.parent = &system_bus; + pr_debug("Suspending System Devices\n"); + + if (!down_write_trylock(&system_subsys.rwsem)) { + printk("%s: Cannot acquire semaphore; Failing\n",__FUNCTION__); + return -EFAULT; } - /* make sure bus type is set */ - if (!sysdev->dev.bus) - sysdev->dev.bus = &system_bus_type; + list_for_each_entry_reverse(cls,&system_subsys.kset.list, + kset.kobj.entry) { + struct sys_device * sysdev; + + pr_debug("Suspending type '%s':\n",cls->kset.kobj.name); - /* construct bus_id */ - snprintf(sysdev->dev.bus_id,BUS_ID_SIZE,"%s%u",sysdev->name,sysdev->id); + list_for_each_entry(sysdev,&cls->kset.list,kobj.entry) { + struct sysdev_driver * drv; + pr_debug(" %s\n",sysdev->kobj.name); - pr_debug("Registering system device %s\n", sysdev->dev.bus_id); + /* Call global drivers first. */ + list_for_each_entry(drv,&global_drivers,entry) { + if (drv->suspend) + drv->suspend(sysdev,state); + } - return device_register(&sysdev->dev); + /* Call auxillary drivers next. */ + list_for_each_entry(drv,&cls->drivers,entry) { + if (drv->suspend) + drv->suspend(sysdev,state); + } + + /* Now call the generic one */ + if (cls->suspend) + cls->suspend(sysdev,state); + } + } + up_write(&system_subsys.rwsem); + + return 0; } -void sys_device_unregister(struct sys_device * sysdev) + +/** + * sys_device_resume - Bring system devices back to life. + * + * Similar to sys_device_suspend(), but we iterate the list forwards + * to guarantee that parent devices are resumed before their children. + * + * Note: Interrupts are disabled when called. + */ + +int sys_device_resume(void) { - if (sysdev) - device_unregister(&sysdev->dev); -} + struct sysdev_class * cls; + + pr_debug("Resuming System Devices\n"); + + if(!down_write_trylock(&system_subsys.rwsem)) + return -EFAULT; + + list_for_each_entry(cls,&system_subsys.kset.list,kset.kobj.entry) { + struct sys_device * sysdev; + + pr_debug("Resuming type '%s':\n",cls->kset.kobj.name); -struct bus_type system_bus_type = { - .name = "system", -}; + list_for_each_entry(sysdev,&cls->kset.list,kobj.entry) { + struct sysdev_driver * drv; + pr_debug(" %s\n",sysdev->kobj.name); + + /* Call global drivers first. */ + list_for_each_entry(drv,&global_drivers,entry) { + if (drv->resume) + drv->resume(sysdev); + } + + /* Call auxillary drivers next. */ + list_for_each_entry(drv,&cls->drivers,entry) { + if (drv->resume) + drv->resume(sysdev); + } + + /* Now call the generic one */ + if (cls->resume) + cls->resume(sysdev); + } + } + up_write(&system_subsys.rwsem); + return 0; +} int __init sys_bus_init(void) { - bus_register(&system_bus_type); - return device_register(&system_bus); + system_subsys.kset.kobj.parent = &devices_subsys.kset.kobj; + return subsystem_register(&system_subsys); } -EXPORT_SYMBOL(system_bus_type); EXPORT_SYMBOL(sys_device_register); EXPORT_SYMBOL(sys_device_unregister); -- cgit v1.2.3 From 9777b1def2c760ad5c3b2185ee7376836576b48c Mon Sep 17 00:00:00 2001 From: Patrick Mochel Date: Mon, 9 Jun 2003 02:43:08 -0700 Subject: [driver model] Make sure that system devices are handled specially power-wise - Suspend system devices last, after interrupts have been enabled. - Resume them first, before interrupts are enabled. - Shut them down last, after everything else. --- drivers/base/power.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/power.c b/drivers/base/power.c index e389891c574d..081ad32cadfd 100644 --- a/drivers/base/power.c +++ b/drivers/base/power.c @@ -21,6 +21,19 @@ extern struct subsystem devices_subsys; +/** + * We handle system devices differently - we suspend and shut them + * down first and resume them first. That way, we do anything stupid like + * shutting down the interrupt controller before any devices.. + * + * Note that there are not different stages for power management calls - + * they only get one called once when interrupts are disabled. + */ + +extern int sys_device_shutdown(void); +extern int sys_device_suspend(u32 state); +extern int sys_device_resume(void); + /** * device_suspend - suspend/remove all devices on the device ree * @state: state we're entering @@ -50,6 +63,10 @@ int device_suspend(u32 state, u32 level) } } up_write(&devices_subsys.rwsem); + + if (level == SUSPEND_POWER_DOWN) + sys_device_suspend(state); + return error; } @@ -65,6 +82,9 @@ void device_resume(u32 level) { struct list_head * node; + if (level == RESUME_POWER_ON) + sys_device_resume(); + down_write(&devices_subsys.rwsem); list_for_each_prev(node,&devices_subsys.kset.list) { struct device * dev = to_dev(node); @@ -98,6 +118,8 @@ void device_shutdown(void) pr_debug("Ignored.\n"); } up_write(&devices_subsys.rwsem); + + sys_device_shutdown(); } EXPORT_SYMBOL(device_suspend); -- cgit v1.2.3 From 60c37a8b605f5b372f53c536f2adfa3628a95184 Mon Sep 17 00:00:00 2001 From: Patrick Mochel Date: Mon, 9 Jun 2003 02:44:27 -0700 Subject: [driver model] Convert to new system device API --- drivers/base/cpu.c | 46 ++++++---------------------------------------- 1 file changed, 6 insertions(+), 40 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index c02afc0b6deb..f30b746a2ec5 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -9,15 +9,8 @@ #include - -struct class cpu_class = { - .name = "cpu", -}; - - -struct device_driver cpu_driver = { - .name = "cpu", - .bus = &system_bus_type, +struct sysdev_class cpu_sysdev_class = { + set_kset_name("cpu"), }; /* @@ -28,42 +21,15 @@ struct device_driver cpu_driver = { */ int __init register_cpu(struct cpu *cpu, int num, struct node *root) { - int retval; - cpu->node_id = cpu_to_node(num); - cpu->sysdev.name = "cpu"; cpu->sysdev.id = num; - if (root) - cpu->sysdev.root = &root->sysroot; - snprintf(cpu->sysdev.dev.name, DEVICE_NAME_SIZE, "CPU %u", num); - cpu->sysdev.dev.driver = &cpu_driver; - retval = sys_device_register(&cpu->sysdev); - if (retval) - return retval; - memset(&cpu->sysdev.class_dev, 0x00, sizeof(struct class_device)); - cpu->sysdev.class_dev.dev = &cpu->sysdev.dev; - cpu->sysdev.class_dev.class = &cpu_class; - snprintf(cpu->sysdev.class_dev.class_id, BUS_ID_SIZE, "cpu%d", num); - retval = class_device_register(&cpu->sysdev.class_dev); - if (retval) { - sys_device_unregister(&cpu->sysdev); - return retval; - } - return 0; + cpu->sysdev.cls = &cpu_sysdev_class; + return sys_device_register(&cpu->sysdev); } + int __init cpu_dev_init(void) { - int error; - - error = class_register(&cpu_class); - if (error) - goto out; - - error = driver_register(&cpu_driver); - if (error) - class_unregister(&cpu_class); -out: - return error; + return sysdev_class_register(&cpu_sysdev_class); } -- cgit v1.2.3 From 35e5d23476e00fb2d709b90d8fb4cc4a9caa660c Mon Sep 17 00:00:00 2001 From: Patrick Mochel Date: Mon, 9 Jun 2003 21:58:22 -0700 Subject: [driver model] Create include/linux/sysdev.h and define sysdev_attribute. Split out all system device definitions from device.h into their own header sysdev.h Define struct sysdev_attribute and define functions to export attributes in sysfs. --- drivers/base/sys.c | 41 ++++++++++++++++++++-- include/linux/sysdev.h | 94 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 133 insertions(+), 2 deletions(-) create mode 100644 include/linux/sysdev.h (limited to 'drivers/base') diff --git a/drivers/base/sys.c b/drivers/base/sys.c index aa71e40a865e..6ae79a036f0f 100644 --- a/drivers/base/sys.c +++ b/drivers/base/sys.c @@ -14,7 +14,7 @@ #define DEBUG -#include +#include #include #include #include @@ -25,10 +25,47 @@ extern struct subsystem devices_subsys; +#define to_sysdev(k) container_of(k,struct sys_device,kobj) +#define to_sysdev_attr(a) container_of(a,struct sysdev_attribute,attr) + + +static ssize_t +sysdev_show(struct kobject * kobj, struct attribute * attr, char * buffer) +{ + struct sys_device * sysdev = to_sysdev(kobj); + struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr); + + if (sysdev_attr->show) + return sysdev_attr->show(sysdev,buffer); + return 0; +} + + +static ssize_t +sysdev_store(struct kobject * kobj, struct attribute * attr, + const char * buffer, size_t count) +{ + struct sys_device * sysdev = to_sysdev(kobj); + struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr); + + if (sysdev_attr->store) + return sysdev_attr->store(sysdev,buffer,count); + return 0; +} + +static struct sysfs_ops sysfs_ops = { + .show = sysdev_show, + .store = sysdev_store, +}; + +static struct kobj_type ktype_sysdev = { + .sysfs_ops = &sysfs_ops, +}; + /* * declare system_subsys */ -decl_subsys(system,NULL,NULL); +decl_subsys(system,&ktype_sysdev,NULL); int sysdev_class_register(struct sysdev_class * cls) { diff --git a/include/linux/sysdev.h b/include/linux/sysdev.h new file mode 100644 index 000000000000..2a90db8d41de --- /dev/null +++ b/include/linux/sysdev.h @@ -0,0 +1,94 @@ +/** + * System devices follow a slightly different driver model. + * They don't need to do dynammic driver binding, can't be probed, + * and don't reside on any type of peripheral bus. + * So, we represent and treat them a little differently. + * + * We still have a notion of a driver for a system device, because we still + * want to perform basic operations on these devices. + * + * We also support auxillary drivers binding to devices of a certain class. + * + * This allows configurable drivers to register themselves for devices of + * a certain type. And, it allows class definitions to reside in generic + * code while arch-specific code can register specific drivers. + * + * Auxillary drivers registered with a NULL cls are registered as drivers + * for all system devices, and get notification calls for each device. + */ + + +#ifndef _SYSDEV_H_ +#define _SYSDEV_H_ + +#include + + +struct sys_device; + +struct sysdev_class { + struct list_head drivers; + + /* Default operations for these types of devices */ + int (*shutdown)(struct sys_device *); + int (*suspend)(struct sys_device *, u32 state); + int (*resume)(struct sys_device *); + struct kset kset; +}; + + +extern int sysdev_class_register(struct sysdev_class *); +extern void sysdev_class_unregister(struct sysdev_class *); + + +/** + * Auxillary system device drivers. + */ + +struct sysdev_driver { + struct list_head entry; + int (*add)(struct sys_device *); + int (*remove)(struct sys_device *); + int (*shutdown)(struct sys_device *); + int (*suspend)(struct sys_device *, u32 state); + int (*resume)(struct sys_device *); +}; + + +extern int sysdev_driver_register(struct sysdev_class *, struct sysdev_driver *); +extern void sysdev_driver_unregister(struct sysdev_class *, struct sysdev_driver *); + + +/** + * sys_devices can be simplified a lot from regular devices, because they're + * simply not as versatile. + */ + +struct sys_device { + u32 id; + struct sysdev_class * cls; + struct kobject kobj; +}; + +extern int sys_device_register(struct sys_device *); +extern void sys_device_unregister(struct sys_device *); + + +struct sysdev_attribute { + struct attribute attr; + ssize_t (*show)(struct sys_device *, char *); + ssize_t (*store)(struct sys_device *, const char *, size_t); +}; + + +#define SYSDEV_ATTR(_name,_mode,_show,_store) \ +struct sysdev_attribute attr_##_name = { \ + .attr = {.name = __stringify(_name), .mode = _mode }, \ + .show = _show, \ + .store = _store, \ +}; + +extern int sysdev_create_file(struct sys_device *, struct sysdev_attribute *); +extern void sysdev_remove_file(struct sys_device *, struct sysdev_attribute *); + +#endif /* _SYSDEV_H_ */ -- cgit v1.2.3 From 22ff2891d8ab22a6559a55f6ba1496298b53c3f0 Mon Sep 17 00:00:00 2001 From: Patrick Mochel Date: Mon, 9 Jun 2003 21:59:13 -0700 Subject: [driver model] Make sure right header is used for cpu.c --- drivers/base/cpu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index f30b746a2ec5..60e2c4d36990 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -2,7 +2,7 @@ * drivers/base/cpu.c - basic CPU class support */ -#include +#include #include #include #include @@ -13,6 +13,7 @@ struct sysdev_class cpu_sysdev_class = { set_kset_name("cpu"), }; + /* * register_cpu - Setup a driverfs device for a CPU. * @num - CPU number to use when creating the device. -- cgit v1.2.3 From b65b902cf0afa015d5ad6442a15ab942db8c1f26 Mon Sep 17 00:00:00 2001 From: Patrick Mochel Date: Mon, 9 Jun 2003 22:00:07 -0700 Subject: [memblk] Convert to use new system device API --- drivers/base/memblk.c | 31 +++++++++++++------------------ 1 file changed, 13 insertions(+), 18 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/memblk.c b/drivers/base/memblk.c index 4986211b0ca6..3e3d069b5327 100644 --- a/drivers/base/memblk.c +++ b/drivers/base/memblk.c @@ -2,7 +2,6 @@ * drivers/base/memblk.c - basic Memory Block class support */ -#include #include #include #include @@ -11,8 +10,8 @@ #include -static struct class memblk_class = { - .name = "memblk", +static struct sysdev_class memblk_class = { + set_kset_name("memblk"), }; @@ -30,27 +29,23 @@ static struct device_driver memblk_driver = { */ int __init register_memblk(struct memblk *memblk, int num, struct node *root) { + int error; + memblk->node_id = memblk_to_node(num); - memblk->sysdev.name = "memblk"; + memblk->sysdev.cls = &memblk_class, memblk->sysdev.id = num; - if (root) - memblk->sysdev.root = &root->sysroot; - snprintf(memblk->sysdev.dev.name, DEVICE_NAME_SIZE, "Memory Block %u", num); - memblk->sysdev.dev.driver = &memblk_driver; - return sys_device_register(&memblk->sysdev); + + error = sys_device_register(&memblk->sysdev); + if (!error) + error = sysfs_create_link(&root->sysdev.kobj, + &memblk->sysdev,kobj, + memblk->sysdev.kobj.name); + return error; } int __init register_memblk_type(void) { - int error; - - error = class_register(&memblk_class); - if (!error) { - error = driver_register(&memblk_driver); - if (error) - class_unregister(&memblk_class); - } - return error; + return sysdev_class_register(&memblk_class); } postcore_initcall(register_memblk_type); -- cgit v1.2.3 From c81d6bf04f5fd7078b7373cc6cd7c7c917fc9fe9 Mon Sep 17 00:00:00 2001 From: Patrick Mochel Date: Mon, 9 Jun 2003 22:00:51 -0700 Subject: [numa nodes] Convert to use new system device API --- drivers/base/node.c | 41 +++++++++++------------------------------ include/linux/node.h | 4 ++-- 2 files changed, 13 insertions(+), 32 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/node.c b/drivers/base/node.c index 48fa6de5580a..8dc7ab848216 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -10,15 +10,8 @@ #include - -static struct class node_class = { - .name = "node", -}; - - -static struct device_driver node_driver = { - .name = "node", - .bus = &system_bus_type, +static struct sysdev_class node_class = { + set_kset_name("node"), }; @@ -27,7 +20,7 @@ static ssize_t node_read_cpumap(struct device * dev, char * buf) struct node *node_dev = to_node(to_root(dev)); return sprintf(buf,"%lx\n",node_dev->cpumap); } -static DEVICE_ATTR(cpumap,S_IRUGO,node_read_cpumap,NULL); +static SYSDEV_ATTR(cpumap,S_IRUGO,node_read_cpumap,NULL); #define K(x) ((x) << (PAGE_SHIFT - 10)) static ssize_t node_read_meminfo(struct device * dev, char * buf) @@ -53,7 +46,7 @@ static ssize_t node_read_meminfo(struct device * dev, char * buf) nid, K(i.freeram-i.freehigh)); } #undef K -static DEVICE_ATTR(meminfo,S_IRUGO,node_read_meminfo,NULL); +static SYSDEV_ATTR(meminfo,S_IRUGO,node_read_meminfo,NULL); /* @@ -67,17 +60,13 @@ int __init register_node(struct node *node, int num, struct node *parent) int error; node->cpumap = node_to_cpumask(num); - node->sysroot.id = num; - if (parent) - node->sysroot.dev.parent = &parent->sysroot.sysdev; - snprintf(node->sysroot.dev.name, DEVICE_NAME_SIZE, "Node %u", num); - snprintf(node->sysroot.dev.bus_id, BUS_ID_SIZE, "node%u", num); - node->sysroot.dev.driver = &node_driver; - node->sysroot.dev.bus = &system_bus_type; - error = sys_register_root(&node->sysroot); + node->sysdev.id = num; + node->sysdev.cls = &node_class; + error = sys_device_register(&node->sysdev); + if (!error){ - device_create_file(&node->sysroot.dev, &dev_attr_cpumap); - device_create_file(&node->sysroot.dev, &dev_attr_meminfo); + sys_device_create_file(&node->sysroot.dev, &attr_cpumap); + sys_device_create_file(&node->sysroot.dev, &attr_meminfo); } return error; } @@ -85,14 +74,6 @@ int __init register_node(struct node *node, int num, struct node *parent) int __init register_node_type(void) { - int error; - - error = class_register(&node_class); - if (!error) { - error = driver_register(&node_driver); - if (error) - class_unregister(&node_class); - } - return error; + return sysdev_class_register(&node_class); } postcore_initcall(register_node_type); diff --git a/include/linux/node.h b/include/linux/node.h index 294606bbff5a..90543a94b86e 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -19,11 +19,11 @@ #ifndef _LINUX_NODE_H_ #define _LINUX_NODE_H_ -#include +#include struct node { unsigned long cpumap; /* Bitmap of CPUs on the Node */ - struct sys_root sysroot; + struct sys_device sysdev; }; extern int register_node(struct node *, int, struct node *); -- cgit v1.2.3 From d507789a02e933ab503a4457abd6f56c579dea05 Mon Sep 17 00:00:00 2001 From: Patrick Mochel Date: Mon, 9 Jun 2003 23:58:37 -0700 Subject: [driver model] Add save() and restore() methods for system device drivers. It turns out that at least some system device drivers need to allocate memory and/or sleep for one reason or another when either saving or restoring state. Instead of adding a 'level' paramter to the suspend() and resume() methods, which I despise and think is a horrible programming interface, two new methods have been added to struct sysdev_driver: int (*save)(struct sys_device *, u32 state); int (*restore)(struct sys_device *); that are called explicitly before and after suspend() and resume() respectively, with interrupts enabled. This gives the drivers the flexibility to allocate memory and sleep, if necessary. --- drivers/base/power.c | 37 ++++++++++++---- drivers/base/sys.c | 117 +++++++++++++++++++++++++++++++++++++++++++------ include/linux/sysdev.h | 4 ++ 3 files changed, 137 insertions(+), 21 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power.c b/drivers/base/power.c index 081ad32cadfd..7f5a6abc4e00 100644 --- a/drivers/base/power.c +++ b/drivers/base/power.c @@ -30,9 +30,11 @@ extern struct subsystem devices_subsys; * they only get one called once when interrupts are disabled. */ -extern int sys_device_shutdown(void); -extern int sys_device_suspend(u32 state); -extern int sys_device_resume(void); +extern int sysdev_shutdown(void); +extern int sysdev_save(u32 state); +extern int sysdev_suspend(u32 state); +extern int sysdev_resume(void); +extern int sysdev_restore(void); /** * device_suspend - suspend/remove all devices on the device ree @@ -64,8 +66,19 @@ int device_suspend(u32 state, u32 level) } up_write(&devices_subsys.rwsem); - if (level == SUSPEND_POWER_DOWN) - sys_device_suspend(state); + /* + * Make sure system devices are suspended. + */ + switch(level) { + case SUSPEND_SAVE_STATE: + sysdev_save(state); + break; + case SUSPEND_POWER_DOWN: + sysdev_suspend(state); + break; + default: + break; + } return error; } @@ -82,8 +95,16 @@ void device_resume(u32 level) { struct list_head * node; - if (level == RESUME_POWER_ON) - sys_device_resume(); + switch (level) { + case RESUME_POWER_ON: + sysdev_resume(); + break; + case RESUME_RESTORE_STATE: + sysdev_restore(); + break; + default: + break; + } down_write(&devices_subsys.rwsem); list_for_each_prev(node,&devices_subsys.kset.list) { @@ -119,7 +140,7 @@ void device_shutdown(void) } up_write(&devices_subsys.rwsem); - sys_device_shutdown(); + sysdev_shutdown(); } EXPORT_SYMBOL(device_suspend); diff --git a/drivers/base/sys.c b/drivers/base/sys.c index 6ae79a036f0f..3d6d2e1d1147 100644 --- a/drivers/base/sys.c +++ b/drivers/base/sys.c @@ -200,7 +200,7 @@ void sys_device_unregister(struct sys_device * sysdev) /** - * sys_device_shutdown - Shut down all system devices. + * sysdev_shutdown - Shut down all system devices. * * Loop over each class of system devices, and the devices in each * of those classes. For each device, we call the shutdown method for @@ -213,7 +213,7 @@ void sys_device_unregister(struct sys_device * sysdev) * after their parents. */ -void sys_device_shutdown(void) +void sysdev_shutdown(void) { struct sysdev_class * cls; @@ -252,7 +252,53 @@ void sys_device_shutdown(void) /** - * sys_device_suspend - Suspend all system devices. + * sysdev_save - Save system device state + * @state: Power state we're entering. + * + * This is called when the system is going to sleep, but before interrupts + * have been disabled. This allows system device drivers to allocate and + * save device state, including sleeping during the process.. + */ + +int sysdev_save(u32 state) +{ + struct sysdev_class * cls; + + pr_debug("Saving System Device State\n"); + + down_write(&system_subsys.rwsem); + + list_for_each_entry_reverse(cls,&system_subsys.kset.list, + kset.kobj.entry) { + struct sys_device * sysdev; + pr_debug("Saving state for type '%s':\n",cls->kset.kobj.name); + + list_for_each_entry(sysdev,&cls->kset.list,kobj.entry) { + struct sysdev_driver * drv; + + pr_debug(" %s\n",sysdev->kobj.name); + + list_for_each_entry(drv,&global_drivers,entry) { + if (drv->save) + drv->save(sysdev,state); + } + + list_for_each_entry(drv,&cls->drivers,entry) { + if (drv->save) + drv->save(sysdev,state); + } + + if (cls->save) + cls->save(sysdev,state); + } + } + up_write(&system_subsys.rwsem); + return 0; +} + + +/** + * sysdev_suspend - Suspend all system devices. * @state: Power state to enter. * * We perform an almost identical operation as sys_device_shutdown() @@ -263,7 +309,7 @@ void sys_device_shutdown(void) * warning and return an error. */ -int sys_device_suspend(u32 state) +int sysdev_suspend(u32 state) { struct sysdev_class * cls; @@ -308,7 +354,7 @@ int sys_device_suspend(u32 state) /** - * sys_device_resume - Bring system devices back to life. + * sysdev_resume - Bring system devices back to life. * * Similar to sys_device_suspend(), but we iterate the list forwards * to guarantee that parent devices are resumed before their children. @@ -316,7 +362,7 @@ int sys_device_suspend(u32 state) * Note: Interrupts are disabled when called. */ -int sys_device_resume(void) +int sysdev_resume(void) { struct sysdev_class * cls; @@ -334,27 +380,72 @@ int sys_device_resume(void) struct sysdev_driver * drv; pr_debug(" %s\n",sysdev->kobj.name); - /* Call global drivers first. */ - list_for_each_entry(drv,&global_drivers,entry) { + /* First, call the class-specific one */ + if (cls->resume) + cls->resume(sysdev); + + /* Call auxillary drivers next. */ + list_for_each_entry(drv,&cls->drivers,entry) { if (drv->resume) drv->resume(sysdev); } - /* Call auxillary drivers next. */ - list_for_each_entry(drv,&cls->drivers,entry) { + /* Call global drivers. */ + list_for_each_entry(drv,&global_drivers,entry) { if (drv->resume) drv->resume(sysdev); } - /* Now call the generic one */ - if (cls->resume) - cls->resume(sysdev); } } up_write(&system_subsys.rwsem); return 0; } + +/** + * sysdev_restore - Restore system device state + * + * This is called during a suspend/resume cycle last, after interrupts + * have been re-enabled. This is intended for auxillary drivers, etc, + * that may sleep when restoring state. + */ + +int sysdev_restore(void) +{ + struct sysdev_class * cls; + + down_write(&system_subsys.rwsem); + pr_debug("Restoring System Device State\n"); + + list_for_each_entry(cls,&system_subsys.kset.list,kset.kobj.entry) { + struct sys_device * sysdev; + + pr_debug("Restoring state for type '%s':\n",cls->kset.kobj.name); + list_for_each_entry(sysdev,&cls->kset.list,kobj.entry) { + struct sysdev_driver * drv; + pr_debug(" %s\n",sysdev->kobj.name); + + if (cls->restore) + cls->restore(sysdev); + + list_for_each_entry(drv,&cls->drivers,entry) { + if (drv->restore) + drv->restore(sysdev); + } + + list_for_each_entry(drv,&global_drivers,entry) { + if (drv->restore) + drv->restore(sysdev); + } + } + } + + up_write(&system_subsys.rwsem); + return 0; +} + + int __init sys_bus_init(void) { system_subsys.kset.kobj.parent = &devices_subsys.kset.kobj; diff --git a/include/linux/sysdev.h b/include/linux/sysdev.h index 2a90db8d41de..4bc3e22b5104 100644 --- a/include/linux/sysdev.h +++ b/include/linux/sysdev.h @@ -31,8 +31,10 @@ struct sysdev_class { /* Default operations for these types of devices */ int (*shutdown)(struct sys_device *); + int (*save)(struct sys_device *, u32 state); int (*suspend)(struct sys_device *, u32 state); int (*resume)(struct sys_device *); + int (*restore)(struct sys_device *); struct kset kset; }; @@ -50,8 +52,10 @@ struct sysdev_driver { int (*add)(struct sys_device *); int (*remove)(struct sys_device *); int (*shutdown)(struct sys_device *); + int (*save)(struct sys_device *, u32 state); int (*suspend)(struct sys_device *, u32 state); int (*resume)(struct sys_device *); + int (*restore)(struct sys_device *); }; -- cgit v1.2.3 From 52815e81f07afbad2f0f61b7a323abb2639e5992 Mon Sep 17 00:00:00 2001 From: Patrick Mochel Date: Tue, 10 Jun 2003 00:26:43 -0700 Subject: [driver model] Don't Oops when registering global sysdev drivers. --- drivers/base/sys.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/sys.c b/drivers/base/sys.c index 3d6d2e1d1147..34001cb52fa1 100644 --- a/drivers/base/sys.c +++ b/drivers/base/sys.c @@ -104,7 +104,7 @@ int sysdev_driver_register(struct sysdev_class * cls, struct sysdev_driver * drv) { down_write(&system_subsys.rwsem); - if (kset_get(&cls->kset)) + if (cls && kset_get(&cls->kset)) list_add_tail(&drv->entry,&cls->drivers); else list_add_tail(&drv->entry,&global_drivers); -- cgit v1.2.3