From: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
If an external connector like M.2 is connected to the serdev controller
in DT, then the serdev devices may be created dynamically by the connector
driver. So do not return -ENODEV from of_serdev_register_devices() if the
static nodes are not found and the graph node is used.
Tested-by: Hans de Goede <johannes.goede@oss.qualcomm.com> # ThinkPad T14s gen6 (arm64)
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
---
drivers/tty/serdev/core.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index bf88b95f7458..e9d044a331b0 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -12,6 +12,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_graph.h>
#include <linux/of_device.h>
#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
@@ -561,7 +562,13 @@ static int of_serdev_register_devices(struct serdev_controller *ctrl)
} else
found = true;
}
- if (!found)
+
+ /*
+ * When the serdev controller is connected to an external connector like
+ * M.2 in DT, then the serdev devices may be created dynamically by the
+ * connector driver.
+ */
+ if (!found && !of_graph_is_present(dev_of_node(&ctrl->dev)))
return -ENODEV;
return 0;
--
2.51.0