[PATCH v2 02/31] fsi: Improve master indexing

Eddie James
2024-02-26T16:53:41Z

Master indexing is problematic if a hub is rescanned while the
root master is being rescanned. Move the IDA free below the device
unregistration, lock the scan mutex in the probe function, and
request a specific idx in the hub driver.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
drivers/fsi/fsi-core.c | 12 +++++-------
drivers/fsi/fsi-master-hub.c | 2 ++
2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c
index 7bf0c96fc017..1c687eb021a0 100644
--- a/drivers/fsi/fsi-core.c
+++ b/drivers/fsi/fsi-core.c
@@ -1271,7 +1271,6 @@ static struct class fsi_master_class = {
int fsi_master_register(struct fsi_master *master)
{
int rc;
- struct device_node *np;

mutex_init(&master->scan_lock);

@@ -1295,14 +1294,13 @@ int fsi_master_register(struct fsi_master *master)
rc = device_register(&master->dev);
if (rc) {
ida_free(&master_ida, master->idx);
- goto out;
- }
+ } else {
+ struct device_node *np = dev_of_node(&master->dev);

- np = dev_of_node(&master->dev);
- if (!of_property_read_bool(np, "no-scan-on-init")) {
- fsi_master_scan(master);
+ if (!of_property_read_bool(np, "no-scan-on-init"))
+ fsi_master_scan(master);
}
-out:
+
mutex_unlock(&master->scan_lock);
return rc;
}
diff --git a/drivers/fsi/fsi-master-hub.c b/drivers/fsi/fsi-master-hub.c
index 6d8b6e8854e5..36da643b3201 100644
--- a/drivers/fsi/fsi-master-hub.c
+++ b/drivers/fsi/fsi-master-hub.c
@@ -12,6 +12,7 @@
#include <linux/slab.h>

#include "fsi-master.h"
+#include "fsi-slave.h"

#define FSI_ENGID_HUB_MASTER 0x1c

@@ -229,6 +230,7 @@ static int hub_master_probe(struct device *dev)
hub->master.dev.release = hub_master_release;
hub->master.dev.of_node = of_node_get(dev_of_node(dev));

+ hub->master.idx = fsi_dev->slave->link + 1;
hub->master.n_links = links;
hub->master.read = hub_master_read;
hub->master.write = hub_master_write;
--
2.39.3