Merge branch 'component-for-driver' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into driver-core-next

Russell writes:

These updates fix one bug in the component helper where the matched
components are not properly cleaned up when the master fails to bind.
I'll provide a version of this for stable trees if it's deemed that
we need to backport it.

The second patch causes the component helper to ignore duplicate
matches when adding components - this is something that was originally
needed for imx-drm, but since that has now been updated, we no longer
need to skip over a component which has already been matched.

The final patch starts the process of updating the component helper
API to achieve two goals: to allow the API to be more efficient when
deferred probing occurs, and to allow for future improvements to the
component helper without having a major impact on the users.

This represents groundwork for some other changes; once this has been
merged, I will then send two further pull requests (one for the staging
tree, and one for the DRM tree) to update the drivers to the new API.
This will result in these three commits being shared with those trees.

1 files changed, 72 insertions, 7 deletions

diff --git a/drivers/s390/cio/qdio_debug.c b/drivers/s390/cio/qdio_debug.c
index 4221b02085ad..f1f3baa8e6e4 100644
--- a/drivers/s390/cio/qdio_debug.c
+++ b/drivers/s390/cio/qdio_debug.c
@@ -7,6 +7,7 @@
 #include <linux/debugfs.h>
 #include <linux/uaccess.h>
 #include <linux/export.h>
+#include <linux/slab.h>
 #include <asm/debug.h>
 #include "qdio_debug.h"
 #include "qdio.h"
@@ -16,11 +17,51 @@ debug_info_t *qdio_dbf_error;
 
 static struct dentry *debugfs_root;
 #define QDIO_DEBUGFS_NAME_LEN	10
+#define QDIO_DBF_NAME_LEN	20
 
-void qdio_allocate_dbf(struct qdio_initialize *init_data,
+struct qdio_dbf_entry {
+	char dbf_name[QDIO_DBF_NAME_LEN];
+	debug_info_t *dbf_info;
+	struct list_head dbf_list;
+};
+
+static LIST_HEAD(qdio_dbf_list);
+static DEFINE_MUTEX(qdio_dbf_list_mutex);
+
+static debug_info_t *qdio_get_dbf_entry(char *name)
+{
+	struct qdio_dbf_entry *entry;
+	debug_info_t *rc = NULL;
+
+	mutex_lock(&qdio_dbf_list_mutex);
+	list_for_each_entry(entry, &qdio_dbf_list, dbf_list) {
+		if (strcmp(entry->dbf_name, name) == 0) {
+			rc = entry->dbf_info;
+			break;
+		}
+	}
+	mutex_unlock(&qdio_dbf_list_mutex);
+	return rc;
+}
+
+static void qdio_clear_dbf_list(void)
+{
+	struct qdio_dbf_entry *entry, *tmp;
+
+	mutex_lock(&qdio_dbf_list_mutex);
+	list_for_each_entry_safe(entry, tmp, &qdio_dbf_list, dbf_list) {
+		list_del(&entry->dbf_list);
+		debug_unregister(entry->dbf_info);
+		kfree(entry);
+	}
+	mutex_unlock(&qdio_dbf_list_mutex);
+}
+
+int qdio_allocate_dbf(struct qdio_initialize *init_data,
 		       struct qdio_irq *irq_ptr)
 {
-	char text[20];
+	char text[QDIO_DBF_NAME_LEN];
+	struct qdio_dbf_entry *new_entry;
 
 	DBF_EVENT("qfmt:%1d", init_data->q_format);
 	DBF_HEX(init_data->adapter_name, 8);
@@ -38,11 +79,34 @@ void qdio_allocate_dbf(struct qdio_initialize *init_data,
 	DBF_EVENT("irq:%8lx", (unsigned long)irq_ptr);
 
 	/* allocate trace view for the interface */
-	snprintf(text, 20, "qdio_%s", dev_name(&init_data->cdev->dev));
-	irq_ptr->debug_area = debug_register(text, 2, 1, 16);
-	debug_register_view(irq_ptr->debug_area, &debug_hex_ascii_view);
-	debug_set_level(irq_ptr->debug_area, DBF_WARN);
-	DBF_DEV_EVENT(DBF_ERR, irq_ptr, "dbf created");
+	snprintf(text, QDIO_DBF_NAME_LEN, "qdio_%s",
+					dev_name(&init_data->cdev->dev));
+	irq_ptr->debug_area = qdio_get_dbf_entry(text);
+	if (irq_ptr->debug_area)
+		DBF_DEV_EVENT(DBF_ERR, irq_ptr, "dbf reused");
+	else {
+		irq_ptr->debug_area = debug_register(text, 2, 1, 16);
+		if (!irq_ptr->debug_area)
+			return -ENOMEM;
+		if (debug_register_view(irq_ptr->debug_area,
+						&debug_hex_ascii_view)) {
+			debug_unregister(irq_ptr->debug_area);
+			return -ENOMEM;
+		}
+		debug_set_level(irq_ptr->debug_area, DBF_WARN);
+		DBF_DEV_EVENT(DBF_ERR, irq_ptr, "dbf created");
+		new_entry = kzalloc(sizeof(struct qdio_dbf_entry), GFP_KERNEL);
+		if (!new_entry) {
+			debug_unregister(irq_ptr->debug_area);
+			return -ENOMEM;
+		}
+		strlcpy(new_entry->dbf_name, text, QDIO_DBF_NAME_LEN);
+		new_entry->dbf_info = irq_ptr->debug_area;
+		mutex_lock(&qdio_dbf_list_mutex);
+		list_add(&new_entry->dbf_list, &qdio_dbf_list);
+		mutex_unlock(&qdio_dbf_list_mutex);
+	}
+	return 0;
 }
 
 static int qstat_show(struct seq_file *m, void *v)
@@ -300,6 +364,7 @@ int __init qdio_debug_init(void)
 
 void qdio_debug_exit(void)
 {
+	qdio_clear_dbf_list();
 	debugfs_remove(debugfs_root);
 	if (qdio_dbf_setup)
 		debug_unregister(qdio_dbf_setup);