Add OF notifier handler needed for creating/destroying spi devices
according to dynamic runtime changes in the DT live tree.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
---
drivers/spi/spi.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 63 insertions(+), 1 deletion(-)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index a98d236..3d8feca 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -2336,6 +2336,57 @@ EXPORT_SYMBOL_GPL(spi_write_then_read);
/*-------------------------------------------------------------------------*/
+#if IS_ENABLED(CONFIG_OF)
+
+static int of_spi_notify(struct notifier_block *nb,
+ unsigned long action, void *arg)
+{
+ struct device_node *dn;
+ struct spi_master *master;
+ struct spi_device *spi;
+
+ if (action == OF_RECONFIG_DYNAMIC_CREATE_DEV) {
+
+ dn = arg;
+
+ master = of_find_spi_master_by_node(dn->parent);
+ if (master == NULL)
+ return NOTIFY_OK; /* not for us */
+
+ spi = of_register_spi_device(master, dn);
+ put_device(&master->dev);
+
+ if (IS_ERR(spi)) {
+ pr_err("%s: failed to create for '%s'\n",
+ __func__, dn->full_name);
+ return notifier_from_errno(PTR_ERR(spi));
+ }
+
+ } else if (action == OF_RECONFIG_DYNAMIC_DESTROY_DEV) {
+
+ dn = arg;
+
+ /* find our device by node */
+ spi = of_find_spi_device_by_node(dn);
+ if (spi == NULL)
+ return NOTIFY_OK; /* no? not meant for us */
+
+ /* unregister takes one ref away */
+ spi_unregister_device(spi);
+
+ /* and put the reference of the find */
+ put_device(&spi->dev);
+
+ } else
+ return NOTIFY_OK;
+
+ return NOTIFY_STOP;
+}
+
+static struct notifier_block spi_of_notifier;
+
+#endif
+
static int __init spi_init(void)
{
int status;
@@ -2353,8 +2404,19 @@ static int __init spi_init(void)
status = class_register(&spi_master_class);
if (status < 0)
goto err2;
- return 0;
+#if IS_ENABLED(CONFIG_OF)
+ spi_of_notifier.notifier_call = of_spi_notify;
+ status = of_reconfig_notifier_register(&spi_of_notifier);
+ if (status)
+ goto err3;
+#endif
+
+ return 0;
+#if IS_ENABLED(CONFIG_OF)
+err3:
+ class_unregister(&spi_master_class);
+#endif
err2:
bus_unregister(&spi_bus_type);
err1:
--
1.7.12
--
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