[PATCH v3 7/7] ACPI / hotplug / PCI: Hotplug notifications from acpi_bus_notify()

From: Rafael J. Wysocki
Date: Sun Feb 02 2014 - 12:07:09 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Since acpi_bus_notify() is executed on all notifications for all
devices anyway, make it execute acpi_device_hotplug() for all
hotplug events instead of installing notify handlers pointing to
the same function for all hotplug devices.

This change reduces both the size and complexity of ACPI-based device
hotplug code. Moreover, since acpi_device_hotplug() only does
significant things for devices that have either an ACPI scan handler,
or a hotplug context with .eject() defined, and those devices
had notify handlers pointing to acpi_hotplug_notify_cb() installed
before anyway, this modification shouldn't change functionality.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/acpi/bus.c | 60 +++++++++++++---------
drivers/acpi/internal.h | 1
drivers/acpi/scan.c | 100 -------------------------------------
drivers/pci/hotplug/acpiphp.h | 1
drivers/pci/hotplug/acpiphp_glue.c | 16 ++---
include/acpi/acpi_bus.h | 2
6 files changed, 46 insertions(+), 134 deletions(-)

Index: linux-pm/drivers/acpi/bus.c
===================================================================
--- linux-pm.orig/drivers/acpi/bus.c
+++ linux-pm/drivers/acpi/bus.c
@@ -340,62 +340,76 @@ static void acpi_bus_osc_support(void)
*/
static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
{
- struct acpi_device *device = NULL;
+ struct acpi_device *adev;
struct acpi_driver *driver;
-
- ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Notification %#02x to handle %p\n",
- type, handle));
+ acpi_status status;
+ u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;

switch (type) {
-
case ACPI_NOTIFY_BUS_CHECK:
- /* TBD */
+ acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
break;

case ACPI_NOTIFY_DEVICE_CHECK:
- /* TBD */
+ acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
break;

case ACPI_NOTIFY_DEVICE_WAKE:
- /* TBD */
+ acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_WAKE event\n");
break;

case ACPI_NOTIFY_EJECT_REQUEST:
- /* TBD */
+ acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
break;

case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
+ acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK_LIGHT event\n");
/* TBD: Exactly what does 'light' mean? */
break;

case ACPI_NOTIFY_FREQUENCY_MISMATCH:
- /* TBD */
+ acpi_handle_err(handle, "Device cannot be configured due "
+ "to a frequency mismatch\n");
break;

case ACPI_NOTIFY_BUS_MODE_MISMATCH:
- /* TBD */
+ acpi_handle_err(handle, "Device cannot be configured due "
+ "to a bus mode mismatch\n");
break;

case ACPI_NOTIFY_POWER_FAULT:
- /* TBD */
+ acpi_handle_err(handle, "Device has suffered a power fault\n");
break;

default:
- ACPI_DEBUG_PRINT((ACPI_DB_INFO,
- "Received unknown/unsupported notification [%08x]\n",
- type));
- break;
+ acpi_handle_warn(handle, "Unsupported event type 0x%x\n", type);
+ ost_code = ACPI_OST_SC_UNRECOGNIZED_NOTIFY;
+ goto err;
}

- acpi_bus_get_acpi_device(handle, &device);
- if (device) {
- driver = device->driver;
- if (driver && driver->ops.notify &&
- (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
- driver->ops.notify(device, type);
+ if (acpi_bus_get_acpi_device(handle, &adev))
+ goto err;

- acpi_bus_put_acpi_device(device);
+ driver = adev->driver;
+ if (driver && driver->ops.notify &&
+ (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
+ driver->ops.notify(adev, type);
+
+ switch (type) {
+ case ACPI_NOTIFY_BUS_CHECK:
+ case ACPI_NOTIFY_DEVICE_CHECK:
+ case ACPI_NOTIFY_EJECT_REQUEST:
+ status = acpi_hotplug_execute(acpi_device_hotplug, adev, type);
+ if (ACPI_SUCCESS(status))
+ return;
+ default:
+ break;
}
+ acpi_bus_put_acpi_device(adev);
+ return;
+
+ err:
+ acpi_evaluate_hotplug_ost(handle, type, ost_code, NULL);
}

/* --------------------------------------------------------------------------
Index: linux-pm/drivers/acpi/internal.h
===================================================================
--- linux-pm.orig/drivers/acpi/internal.h
+++ linux-pm/drivers/acpi/internal.h
@@ -73,6 +73,7 @@ static inline void acpi_lpss_init(void)
#endif

bool acpi_queue_hotplug_work(struct work_struct *work);
+void acpi_device_hotplug(void *data, u32 src);
bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent);

/* --------------------------------------------------------------------------
Index: linux-pm/drivers/acpi/scan.c
===================================================================
--- linux-pm.orig/drivers/acpi/scan.c
+++ linux-pm/drivers/acpi/scan.c
@@ -470,7 +470,7 @@ static int acpi_generic_hotplug_event(st
return -EINVAL;
}

-static void acpi_device_hotplug(void *data, u32 src)
+void acpi_device_hotplug(void *data, u32 src)
{
u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
struct acpi_device *adev = data;
@@ -520,74 +520,6 @@ static void acpi_device_hotplug(void *da
unlock_device_hotplug();
}

-static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *data)
-{
- u32 ost_code = ACPI_OST_SC_SUCCESS;
- struct acpi_device *adev;
- acpi_status status;
-
- switch (type) {
- case ACPI_NOTIFY_BUS_CHECK:
- acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
- break;
-
- case ACPI_NOTIFY_DEVICE_CHECK:
- acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
- break;
-
- case ACPI_NOTIFY_EJECT_REQUEST:
- acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
- break;
-
- case ACPI_NOTIFY_DEVICE_WAKE:
- return;
-
- case ACPI_NOTIFY_FREQUENCY_MISMATCH:
- acpi_handle_err(handle, "Device cannot be configured due "
- "to a frequency mismatch\n");
- goto out;
-
- case ACPI_NOTIFY_BUS_MODE_MISMATCH:
- acpi_handle_err(handle, "Device cannot be configured due "
- "to a bus mode mismatch\n");
- goto out;
-
- case ACPI_NOTIFY_POWER_FAULT:
- acpi_handle_err(handle, "Device has suffered a power fault\n");
- goto out;
-
- default:
- acpi_handle_warn(handle, "Unsupported event type 0x%x\n", type);
- ost_code = ACPI_OST_SC_UNRECOGNIZED_NOTIFY;
- goto out;
- }
-
- ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
- if (acpi_bus_get_acpi_device(handle, &adev))
- goto out;
-
- status = acpi_hotplug_execute(acpi_device_hotplug, adev, type);
- if (ACPI_SUCCESS(status))
- return;
-
- acpi_bus_put_acpi_device(adev);
-
- out:
- acpi_evaluate_hotplug_ost(handle, type, ost_code, NULL);
-}
-
-void acpi_install_hotplug_notify_handler(acpi_handle handle)
-{
- acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
- acpi_hotplug_notify_cb, NULL);
-}
-
-void acpi_remove_hotplug_notify_handler(acpi_handle handle)
-{
- acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
- acpi_hotplug_notify_cb);
-}
-
static ssize_t real_power_state_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -2025,34 +1957,6 @@ void acpi_scan_hotplug_enabled(struct ac
mutex_unlock(&acpi_scan_lock);
}

-static void acpi_scan_init_hotplug(acpi_handle handle, int type)
-{
- struct acpi_device_pnp pnp = {};
- struct acpi_hardware_id *hwid;
- struct acpi_scan_handler *handler;
-
- INIT_LIST_HEAD(&pnp.ids);
- acpi_set_pnp_ids(handle, &pnp, type);
-
- if (!pnp.type.hardware_id)
- goto out;
-
- /*
- * This relies on the fact that acpi_install_notify_handler() will not
- * install the same notify handler routine twice for the same handle.
- */
- list_for_each_entry(hwid, &pnp.ids, list) {
- handler = acpi_scan_match_handler(hwid->id, NULL);
- if (handler) {
- acpi_install_hotplug_notify_handler(handle);
- break;
- }
- }
-
-out:
- acpi_free_pnp_ids(&pnp);
-}
-
static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
void *not_used, void **return_value)
{
@@ -2074,8 +1978,6 @@ static acpi_status acpi_bus_check_add(ac
return AE_OK;
}

- acpi_scan_init_hotplug(handle, type);
-
acpi_add_single_object(&device, handle, type, sta);
if (!device)
return AE_CTRL_DEPTH;
Index: linux-pm/drivers/pci/hotplug/acpiphp_glue.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/acpiphp_glue.c
+++ linux-pm/drivers/pci/hotplug/acpiphp_glue.c
@@ -283,7 +283,6 @@ static acpi_status register_slot(acpi_ha
newfunc = &context->func;
newfunc->function = function;
newfunc->parent = bridge;
- acpi_unlock_hp_context();

if (acpi_has_method(handle, "_EJ0"))
newfunc->flags = FUNC_HAS_EJ0;
@@ -291,8 +290,14 @@ static acpi_status register_slot(acpi_ha
if (acpi_has_method(handle, "_STA"))
newfunc->flags |= FUNC_HAS_STA;

+ /*
+ * Dock stations' notify handler should be used for dock devices instead
+ * of the common one, so clear hp.event in their contexts.
+ */
if (acpi_has_method(handle, "_DCK"))
- newfunc->flags |= FUNC_HAS_DCK;
+ context->hp.event = NULL;
+
+ acpi_unlock_hp_context();

/* search for objects that share the same slot */
list_for_each_entry(slot, &bridge->slots, node)
@@ -360,10 +365,6 @@ static acpi_status register_slot(acpi_ha
pr_debug("failed to register dock device\n");
}

- /* install notify handler */
- if (!(newfunc->flags & FUNC_HAS_DCK))
- acpi_install_hotplug_notify_handler(handle);
-
return AE_OK;
}

@@ -400,9 +401,6 @@ static void cleanup_bridge(struct acpiph

if (is_dock_device(handle))
unregister_hotplug_dock_device(handle);
-
- if (!(func->flags & FUNC_HAS_DCK))
- acpi_remove_hotplug_notify_handler(handle);
}
slot->flags |= SLOT_IS_GOING_AWAY;
if (slot->slot)
Index: linux-pm/include/acpi/acpi_bus.h
===================================================================
--- linux-pm.orig/include/acpi/acpi_bus.h
+++ linux-pm/include/acpi/acpi_bus.h
@@ -443,8 +443,6 @@ static inline bool acpi_device_enumerate
typedef void (*acpi_hp_callback)(void *data, u32 src);

acpi_status acpi_hotplug_execute(acpi_hp_callback func, void *data, u32 src);
-void acpi_install_hotplug_notify_handler(acpi_handle handle);
-void acpi_remove_hotplug_notify_handler(acpi_handle handle);

/**
* module_acpi_driver(acpi_driver) - Helper macro for registering an ACPI driver
Index: linux-pm/drivers/pci/hotplug/acpiphp.h
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/acpiphp.h
+++ linux-pm/drivers/pci/hotplug/acpiphp.h
@@ -167,7 +167,6 @@ struct acpiphp_attention_info

#define FUNC_HAS_STA (0x00000001)
#define FUNC_HAS_EJ0 (0x00000002)
-#define FUNC_HAS_DCK (0x00000004)

/* function prototypes */


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