From: James Morse <james.morse@xxxxxxx>
struct acpi_scan_handler has a detach callback that is used to remove
a driver when a bus is changed. When interacting with an eject-request,
the detach callback is called before _EJ0.
This means the ACPI processor driver can't use _STA to determine if a
CPU has been made not-present, or some of the other _STA bits have been
changed. acpi_processor_remove() needs to know the value of _STA after
_EJ0 has been called.
Add a post_eject callback to struct acpi_scan_handler. This is called
after acpi_scan_hot_remove() has successfully called _EJ0. Because
acpi_scan_check_and_detach() also clears the handler pointer,
it needs to be told if the caller will go on to call
acpi_bus_post_eject(), so that acpi_device_clear_enumerated()
and clearing the handler pointer can be deferred.
The extra eject flag added in the previous patch is used for this
purpose.
Signed-off-by: James Morse <james.morse@xxxxxxx>
Reviewed-by: Joanthan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Reviewed-by: Gavin Shan <gshan@xxxxxxxxxx>
Tested-by: Miguel Luis <miguel.luis@xxxxxxxxxx>
Tested-by: Vishnu Pajjuri <vishnu@xxxxxxxxxxxxxxxxxxxxxx>
Tested-by: Jianyong Wu <jianyong.wu@xxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
----
Russell, you hadn't signed off on this when posting last time.
Do you want to insert a suitable tag now?
v5:
- Rebase to take into account the changes to scan handling in the
meantime.
---
drivers/acpi/acpi_processor.c | 4 ++--
drivers/acpi/scan.c | 32 +++++++++++++++++++++++++++++---
include/acpi/acpi_bus.h | 1 +
3 files changed, 32 insertions(+), 5 deletions(-)
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 3aa43dee4391..6b2ee0643d11 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -463,7 +463,7 @@ static int acpi_processor_add(struct acpi_device *device,
#ifdef CONFIG_ACPI_HOTPLUG_CPU
/* Removal */
-static void acpi_processor_remove(struct acpi_device *device)
+static void acpi_processor_post_eject(struct acpi_device *device)
{
struct acpi_processor *pr;
@@ -631,7 +631,7 @@ static struct acpi_scan_handler processor_handler = {
.ids = processor_device_ids,
.attach = acpi_processor_add,
#ifdef CONFIG_ACPI_HOTPLUG_CPU
- .detach = acpi_processor_remove,
+ .post_eject = acpi_processor_post_eject,
#endif
.hotplug = {
.enabled = true,
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 79b1f4d2b6bd..992779ac31d4 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -276,8 +276,6 @@ static int acpi_scan_check_and_detach(struct acpi_device *adev, void *p)
if (handler) {
if (handler->detach)
handler->detach(adev);
-
- adev->handler = NULL;
} else {
device_release_driver(&adev->dev);
}
@@ -287,6 +285,28 @@ static int acpi_scan_check_and_detach(struct acpi_device *adev, void *p)
*/
acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
adev->flags.initialized = false;
+
+ /* For eject this is deferred to acpi_bus_post_eject() */
+ if (!param->eject) {
+ adev->handler = NULL;
+ acpi_device_clear_enumerated(adev);
+ }
+ return 0;
+}
+
+static int acpi_bus_post_eject(struct acpi_device *adev, void *not_used)
+{
+ struct acpi_scan_handler *handler = adev->handler;
+
+ acpi_dev_for_each_child_reverse(adev, acpi_bus_post_eject, NULL);
+
+ if (handler) {
+ if (handler->post_eject)
+ handler->post_eject(adev);
+
+ adev->handler = NULL;
+ }
+
acpi_device_clear_enumerated(adev);
return 0;
@@ -306,6 +326,10 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
acpi_handle handle = device->handle;
unsigned long long sta;
acpi_status status;
+ struct acpi_scan_c_and_d_param p = {
+ .check_status = false, /* Not update until after ej0 */
+ .eject = true,
+ };
if (device->handler && device->handler->hotplug.demand_offline) {
if (!acpi_scan_is_offline(device, true))
@@ -318,7 +342,7 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
acpi_handle_debug(handle, "Ejecting\n");
- acpi_bus_trim(device);
+ acpi_scan_check_and_detach(device, &p);
acpi_evaluate_lck(handle, 0);
/*
@@ -341,6 +365,8 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
} else if (sta & ACPI_STA_DEVICE_ENABLED) {
acpi_handle_warn(handle,
"Eject incomplete - status 0x%llx\n", sta);
+ } else {
+ acpi_bus_post_eject(device, NULL);
}
return 0;
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index e193507fd743..27fdef17abe5 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -130,6 +130,7 @@ struct acpi_scan_handler {
bool (*match)(const char *idstr, const struct acpi_device_id **matchid);
int (*attach)(struct acpi_device *dev, const struct acpi_device_id *id);
void (*detach)(struct acpi_device *dev);
+ void (*post_eject)(struct acpi_device *dev);
void (*bind)(struct device *phys_dev);
void (*unbind)(struct device *phys_dev);
struct acpi_hotplug_profile hotplug;
--
2.39.2
