[PATCH v4 5/5] tty_port: register tty ports with serdev bus

From: Rob Herring
Date: Thu Feb 02 2017 - 14:48:45 EST


Register a serdev controller with the serdev bus when a tty_port is
registered. This creates the serdev controller and create's serdev
devices for any DT child nodes of the tty_port's parent (i.e. the UART
device).

Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
Reviewed-By: Sebastian Reichel <sre@xxxxxxxxxx>
Tested-By: Sebastian Reichel <sre@xxxxxxxxxx>
---
v4:
- no change
v3:
- no change

v2:
- Skip creating the tty device file node when serdev_tty_port_register
finds slave devices.

drivers/tty/tty_port.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 8d9886b06037..5cd3cd932293 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -16,6 +16,7 @@
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/module.h>
+#include <linux/serdev.h>

static int tty_port_default_receive_buf(struct tty_port *port,
const unsigned char *p,
@@ -128,7 +129,15 @@ struct device *tty_port_register_device_attr(struct tty_port *port,
struct device *device, void *drvdata,
const struct attribute_group **attr_grp)
{
+ struct device *dev;
+
tty_port_link_device(port, driver, index);
+
+ dev = serdev_tty_port_register(port, device, driver, index);
+ if (PTR_ERR(dev) != -ENODEV)
+ /* Skip creating cdev if we registered a serdev device */
+ return dev;
+
return tty_register_device_attr(driver, index, device, drvdata,
attr_grp);
}
@@ -180,6 +189,9 @@ static void tty_port_destructor(struct kref *kref)
/* check if last port ref was dropped before tty release */
if (WARN_ON(port->itty))
return;
+
+ serdev_tty_port_unregister(port);
+
if (port->xmit_buf)
free_page((unsigned long)port->xmit_buf);
tty_port_destroy(port);
--
2.10.1