diff options
author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-03-03 22:05:29 (GMT) |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-03-04 13:25:32 (GMT) |
commit | a33ec399e9fc266ba20f9b71d693aa63658bf2aa (patch) | |
tree | 404418949973ac053cfe02df039124d7189db1ed /drivers/acpi/scan.c | |
parent | c56980744ed99994799850903627c4bbb5fed006 (diff) | |
download | linux-a33ec399e9fc266ba20f9b71d693aa63658bf2aa.tar.xz |
ACPI / scan: Introduce common code for ACPI-based device hotplug
Multiple drivers handling hotplug-capable ACPI device nodes install
notify handlers covering the same types of events in a very similar
way. Moreover, those handlers are installed in separate namespace
walks, although that really should be done during namespace scans
carried out by acpi_bus_scan(). This leads to substantial code
duplication, unnecessary overhead and behavior that is hard to
follow.
For this reason, introduce common code in drivers/acpi/scan.c for
handling hotplug-related notification and carrying out device
insertion and eject operations in a generic fashion, such that it
may be used by all of the relevant drivers in the future. To cover
the existing differences between those drivers introduce struct
acpi_hotplug_profile for representing collections of hotplug
settings associated with different ACPI scan handlers that can be
used by the drivers to make the common code reflect their current
behavior.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Diffstat (limited to 'drivers/acpi/scan.c')
-rw-r--r-- | drivers/acpi/scan.c | 269 |
1 files changed, 216 insertions, 53 deletions
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index cc1b002..de73fdf 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -107,32 +107,19 @@ acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, cha } static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL); -/** - * acpi_bus_hot_remove_device: hot-remove a device and its children - * @context: struct acpi_eject_event pointer (freed in this func) - * - * Hot-remove a device and its children. This function frees up the - * memory space passed by arg context, so that the caller may call - * this function asynchronously through acpi_os_hotplug_execute(). - */ -void acpi_bus_hot_remove_device(void *context) +static int acpi_scan_hot_remove(struct acpi_device *device) { - struct acpi_eject_event *ej_event = context; - struct acpi_device *device = ej_event->device; acpi_handle handle = device->handle; - acpi_handle temp; + acpi_handle not_used; struct acpi_object_list arg_list; union acpi_object arg; - acpi_status status = AE_OK; - u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */ - - mutex_lock(&acpi_scan_lock); + acpi_status status; /* If there is no handle, the device node has been unregistered. */ - if (!device->handle) { + if (!handle) { dev_dbg(&device->dev, "ACPI handle missing\n"); put_device(&device->dev); - goto out; + return -EINVAL; } ACPI_DEBUG_PRINT((ACPI_DB_INFO, @@ -143,7 +130,7 @@ void acpi_bus_hot_remove_device(void *context) put_device(&device->dev); device = NULL; - if (ACPI_SUCCESS(acpi_get_handle(handle, "_LCK", &temp))) { + if (ACPI_SUCCESS(acpi_get_handle(handle, "_LCK", ¬_used))) { arg_list.count = 1; arg_list.pointer = &arg; arg.type = ACPI_TYPE_INTEGER; @@ -161,18 +148,158 @@ void acpi_bus_hot_remove_device(void *context) */ status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL); if (ACPI_FAILURE(status)) { - if (status != AE_NOT_FOUND) + if (status == AE_NOT_FOUND) { + return -ENODEV; + } else { acpi_handle_warn(handle, "Eject failed\n"); + return -EIO; + } + } + return 0; +} - /* Tell the firmware the hot-remove operation has failed. */ - acpi_evaluate_hotplug_ost(handle, ej_event->event, - ost_code, NULL); +static void acpi_bus_device_eject(void *context) +{ + acpi_handle handle = context; + struct acpi_device *device = NULL; + struct acpi_scan_handler *handler; + u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; + + mutex_lock(&acpi_scan_lock); + + acpi_bus_get_device(handle, &device); + if (!device) + goto err_out; + + handler = device->handler; + if (!handler || !handler->hotplug.enabled) { + ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED; + goto err_out; + } + acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST, + ACPI_OST_SC_EJECT_IN_PROGRESS, NULL); + if (handler->hotplug.mode == AHM_CONTAINER) { + device->flags.eject_pending = true; + kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE); + } else { + int error; + + get_device(&device->dev); + error = acpi_scan_hot_remove(device); + if (error) + goto err_out; } out: mutex_unlock(&acpi_scan_lock); - kfree(context); return; + + err_out: + acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST, ost_code, + NULL); + goto out; +} + +static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source) +{ + struct acpi_device *device = NULL; + u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; + int error; + + mutex_lock(&acpi_scan_lock); + + acpi_bus_get_device(handle, &device); + if (device) { + dev_warn(&device->dev, "Attempt to re-insert\n"); + goto out; + } + acpi_evaluate_hotplug_ost(handle, ost_source, + ACPI_OST_SC_INSERT_IN_PROGRESS, NULL); + error = acpi_bus_scan(handle); + if (error) { + acpi_handle_warn(handle, "Namespace scan failure\n"); + goto out; + } + error = acpi_bus_get_device(handle, &device); + if (error) { + acpi_handle_warn(handle, "Missing device node object\n"); + goto out; + } + ost_code = ACPI_OST_SC_SUCCESS; + if (device->handler && device->handler->hotplug.mode == AHM_CONTAINER) + kobject_uevent(&device->dev.kobj, KOBJ_ONLINE); + + out: + acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL); + mutex_unlock(&acpi_scan_lock); +} + +static void acpi_scan_bus_check(void *context) +{ + acpi_scan_bus_device_check((acpi_handle)context, + ACPI_NOTIFY_BUS_CHECK); +} + +static void acpi_scan_device_check(void *context) +{ + acpi_scan_bus_device_check((acpi_handle)context, + ACPI_NOTIFY_DEVICE_CHECK); +} + +static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *not_used) +{ + acpi_osd_exec_callback callback; + acpi_status status; + + switch (type) { + case ACPI_NOTIFY_BUS_CHECK: + acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n"); + callback = acpi_scan_bus_check; + break; + case ACPI_NOTIFY_DEVICE_CHECK: + acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n"); + callback = acpi_scan_device_check; + break; + case ACPI_NOTIFY_EJECT_REQUEST: + acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n"); + callback = acpi_bus_device_eject; + break; + default: + /* non-hotplug event; possibly handled by other handler */ + return; + } + status = acpi_os_hotplug_execute(callback, handle); + if (ACPI_FAILURE(status)) + acpi_evaluate_hotplug_ost(handle, type, + ACPI_OST_SC_NON_SPECIFIC_FAILURE, + NULL); +} + +/** + * acpi_bus_hot_remove_device: hot-remove a device and its children + * @context: struct acpi_eject_event pointer (freed in this func) + * + * Hot-remove a device and its children. This function frees up the + * memory space passed by arg context, so that the caller may call + * this function asynchronously through acpi_os_hotplug_execute(). + */ +void acpi_bus_hot_remove_device(void *context) +{ + struct acpi_eject_event *ej_event = context; + struct acpi_device *device = ej_event->device; + acpi_handle handle = device->handle; + int error; + + mutex_lock(&acpi_scan_lock); + + error = acpi_scan_hot_remove(device); + if (error && handle) + acpi_evaluate_hotplug_ost(handle, ej_event->event, + ACPI_OST_SC_NON_SPECIFIC_FAILURE, + NULL); + + mutex_unlock(&acpi_scan_lock); + kfree(context); } EXPORT_SYMBOL(acpi_bus_hot_remove_device); @@ -206,51 +333,61 @@ static ssize_t acpi_eject_store(struct device *d, struct device_attribute *attr, const char *buf, size_t count) { - int ret = count; - acpi_status status; - acpi_object_type type = 0; struct acpi_device *acpi_device = to_acpi_device(d); struct acpi_eject_event *ej_event; + acpi_object_type not_used; + acpi_status status; + u32 ost_source; + int ret; - if ((!count) || (buf[0] != '1')) { + if (!count || buf[0] != '1') return -EINVAL; - } - if (!acpi_device->driver && !acpi_device->handler) { - ret = -ENODEV; - goto err; - } - status = acpi_get_type(acpi_device->handle, &type); - if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) { - ret = -ENODEV; - goto err; - } - ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL); - if (!ej_event) { - ret = -ENOMEM; - goto err; - } + if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled) + && !acpi_device->driver) + return -ENODEV; + + status = acpi_get_type(acpi_device->handle, ¬_used); + if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable) + return -ENODEV; + + mutex_lock(&acpi_scan_lock); - get_device(&acpi_device->dev); - ej_event->device = acpi_device; if (acpi_device->flags.eject_pending) { - /* event originated from ACPI eject notification */ - ej_event->event = ACPI_NOTIFY_EJECT_REQUEST; + /* ACPI eject notification event. */ + ost_source = ACPI_NOTIFY_EJECT_REQUEST; acpi_device->flags.eject_pending = 0; } else { - /* event originated from user */ - ej_event->event = ACPI_OST_EC_OSPM_EJECT; - (void) acpi_evaluate_hotplug_ost(acpi_device->handle, - ej_event->event, ACPI_OST_SC_EJECT_IN_PROGRESS, NULL); + /* Eject initiated by user space. */ + ost_source = ACPI_OST_EC_OSPM_EJECT; } - + ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL); + if (!ej_event) { + ret = -ENOMEM; + goto err_out; + } + acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source, + ACPI_OST_SC_EJECT_IN_PROGRESS, NULL); + ej_event->device = acpi_device; + ej_event->event = ost_source; + get_device(&acpi_device->dev); status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event); if (ACPI_FAILURE(status)) { put_device(&acpi_device->dev); kfree(ej_event); + ret = status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN; + goto err_out; } -err: + ret = count; + + out: + mutex_unlock(&acpi_scan_lock); return ret; + + err_out: + acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source, + ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL); + goto out; } static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store); @@ -1555,6 +1692,30 @@ static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr, return NULL; } +static void acpi_scan_init_hotplug(acpi_handle handle) +{ + struct acpi_device_info *info; + struct acpi_scan_handler *handler; + + if (ACPI_FAILURE(acpi_get_object_info(handle, &info))) + return; + + if (!(info->valid & ACPI_VALID_HID)) { + kfree(info); + return; + } + + /* + * This relies on the fact that acpi_install_notify_handler() will not + * install the same notify handler routine twice for the same handle. + */ + handler = acpi_scan_match_handler(info->hardware_id.string, NULL); + kfree(info); + if (handler && handler->hotplug.enabled) + acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY, + acpi_hotplug_notify_cb, NULL); +} + static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used, void *not_used, void **return_value) { @@ -1577,6 +1738,8 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used, return AE_OK; } + acpi_scan_init_hotplug(handle); + if (!(sta & ACPI_STA_DEVICE_PRESENT) && !(sta & ACPI_STA_DEVICE_FUNCTIONING)) { struct acpi_device_wakeup wakeup; |