usb: gadget: push tty port allocation from gadget into f_acm

It possible to allocate the tty port number within the "instance"
structure of the function and there is no need to expose this
information within the gadget and therefore it is removed here.
This patch converts only f_acm and all its users. The other gadgets will
follow once the function is converted to the function interface.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/usb/gadget/f_acm.c b/drivers/usb/gadget/f_acm.c
index 61b33d23be72..ba7daaaad148 100644
--- a/drivers/usb/gadget/f_acm.c
+++ b/drivers/usb/gadget/f_acm.c
@@ -768,17 +768,24 @@ static void acm_free_instance(struct usb_function_instance *fi)
 	struct f_serial_opts *opts;
 
 	opts = container_of(fi, struct f_serial_opts, func_inst);
+	gserial_free_line(opts->port_num);
 	kfree(opts);
 }
 
 static struct usb_function_instance *acm_alloc_instance(void)
 {
 	struct f_serial_opts *opts;
+	int ret;
 
 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 	if (!opts)
 		return ERR_PTR(-ENOMEM);
 	opts->func_inst.free_func_inst = acm_free_instance;
+	ret = gserial_alloc_line(&opts->port_num);
+	if (ret) {
+		kfree(opts);
+		return ERR_PTR(ret);
+	}
 	return &opts->func_inst;
 }
 DECLARE_USB_FUNCTION_INIT(acm, acm_alloc_instance, acm_alloc_func);