usb: gadget: f_serial: convert to new function interface with backward compatibility

Converting f_serial to the new function interface requires converting
the f_serial's function code and its users.

This patch converts the f_serial.c to the new function interface.

The file is now compiled into a separate usb_f_serial.ko module.
The old function interface is provided by means of preprocessor
conditional directives. After all users are converted, the old interface
can be removed.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/Kconfig

@@ -505,6 +505,9 @@ config USB_F_SS_LB
 config USB_U_SERIAL
 	tristate
 
+config USB_F_SERIAL
+	tristate
+
 choice
 	tristate "USB Gadget Drivers"
 	default USB_ETH

drivers/usb/gadget/Makefile

@@ -41,6 +41,8 @@ obj-$(CONFIG_USB_F_ACM)		+= usb_f_acm.o
 usb_f_ss_lb-y			:= f_loopback.o f_sourcesink.o
 obj-$(CONFIG_USB_F_SS_LB)	+= usb_f_ss_lb.o
 obj-$(CONFIG_USB_U_SERIAL)	+= u_serial.o
+usb_f_serial-y			:= f_serial.o
+obj-$(CONFIG_USB_F_SERIAL)	+= usb_f_serial.o
 
 #
 # USB gadget drivers

drivers/usb/gadget/f_serial.c

@@ -12,6 +12,7 @@
 
 #include <linux/slab.h>
 #include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/device.h>
 
 #include "u_serial.h"
@@ -42,7 +43,7 @@ static inline struct f_gser *func_to_gser(struct usb_function *f)
 
 /* interface descriptor: */
 
-static struct usb_interface_descriptor gser_interface_desc __initdata = {
+static struct usb_interface_descriptor gser_interface_desc = {
 	.bLength =		USB_DT_INTERFACE_SIZE,
 	.bDescriptorType =	USB_DT_INTERFACE,
 	/* .bInterfaceNumber = DYNAMIC */
@@ -55,21 +56,21 @@ static struct usb_interface_descriptor gser_interface_desc __initdata = {
 
 /* full speed support: */
 
-static struct usb_endpoint_descriptor gser_fs_in_desc __initdata = {
+static struct usb_endpoint_descriptor gser_fs_in_desc = {
 	.bLength =		USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType =	USB_DT_ENDPOINT,
 	.bEndpointAddress =	USB_DIR_IN,
 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 };
 
-static struct usb_endpoint_descriptor gser_fs_out_desc __initdata = {
+static struct usb_endpoint_descriptor gser_fs_out_desc = {
 	.bLength =		USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType =	USB_DT_ENDPOINT,
 	.bEndpointAddress =	USB_DIR_OUT,
 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 };
 
-static struct usb_descriptor_header *gser_fs_function[] __initdata = {
+static struct usb_descriptor_header *gser_fs_function[] = {
 	(struct usb_descriptor_header *) &gser_interface_desc,
 	(struct usb_descriptor_header *) &gser_fs_in_desc,
 	(struct usb_descriptor_header *) &gser_fs_out_desc,
@@ -78,47 +79,47 @@ static struct usb_descriptor_header *gser_fs_function[] __initdata = {
 
 /* high speed support: */
 
-static struct usb_endpoint_descriptor gser_hs_in_desc __initdata = {
+static struct usb_endpoint_descriptor gser_hs_in_desc = {
 	.bLength =		USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType =	USB_DT_ENDPOINT,
 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 	.wMaxPacketSize =	cpu_to_le16(512),
 };
 
-static struct usb_endpoint_descriptor gser_hs_out_desc __initdata = {
+static struct usb_endpoint_descriptor gser_hs_out_desc = {
 	.bLength =		USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType =	USB_DT_ENDPOINT,
 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 	.wMaxPacketSize =	cpu_to_le16(512),
 };
 
-static struct usb_descriptor_header *gser_hs_function[] __initdata = {
+static struct usb_descriptor_header *gser_hs_function[] = {
 	(struct usb_descriptor_header *) &gser_interface_desc,
 	(struct usb_descriptor_header *) &gser_hs_in_desc,
 	(struct usb_descriptor_header *) &gser_hs_out_desc,
 	NULL,
 };
 
-static struct usb_endpoint_descriptor gser_ss_in_desc __initdata = {
+static struct usb_endpoint_descriptor gser_ss_in_desc = {
 	.bLength =		USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType =	USB_DT_ENDPOINT,
 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 	.wMaxPacketSize =	cpu_to_le16(1024),
 };
 
-static struct usb_endpoint_descriptor gser_ss_out_desc __initdata = {
+static struct usb_endpoint_descriptor gser_ss_out_desc = {
 	.bLength =		USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType =	USB_DT_ENDPOINT,
 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 	.wMaxPacketSize =	cpu_to_le16(1024),
 };
 
-static struct usb_ss_ep_comp_descriptor gser_ss_bulk_comp_desc __initdata = {
+static struct usb_ss_ep_comp_descriptor gser_ss_bulk_comp_desc = {
 	.bLength =              sizeof gser_ss_bulk_comp_desc,
 	.bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 };
 
-static struct usb_descriptor_header *gser_ss_function[] __initdata = {
+static struct usb_descriptor_header *gser_ss_function[] = {
 	(struct usb_descriptor_header *) &gser_interface_desc,
 	(struct usb_descriptor_header *) &gser_ss_in_desc,
 	(struct usb_descriptor_header *) &gser_ss_bulk_comp_desc,
@@ -183,14 +184,25 @@ static void gser_disable(struct usb_function *f)
 
 /* serial function driver setup/binding */
 
-static int __init
+static int gser_bind(struct usb_configuration *c, struct usb_function *f)
-gser_bind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct usb_composite_dev *cdev = c->cdev;
 	struct f_gser		*gser = func_to_gser(f);
 	int			status;
 	struct usb_ep		*ep;
 
+	/* REVISIT might want instance-specific strings to help
+	 * distinguish instances ...
+	 */
+
+	/* maybe allocate device-global string ID */
+	if (gser_string_defs[0].id == 0) {
+		status = usb_string_id(c->cdev);
+		if (status < 0)
+			return status;
+		gser_string_defs[0].id = status;
+	}
+
 	/* allocate instance-specific interface IDs */
 	status = usb_interface_id(c, f);
 	if (status < 0)
@@ -246,8 +258,10 @@ fail:
 	return status;
 }
 
+#ifdef USB_FSERIAL_INCLUDED
+
 static void
-gser_unbind(struct usb_configuration *c, struct usb_function *f)
+gser_old_unbind(struct usb_configuration *c, struct usb_function *f)
 {
 	usb_free_all_descriptors(f);
 	kfree(func_to_gser(f));
@@ -266,18 +280,6 @@ int __init gser_bind_config(struct usb_configuration *c, u8 port_num)
 	struct f_gser	*gser;
 	int		status;
 
-	/* REVISIT might want instance-specific strings to help
-	 * distinguish instances ...
-	 */
-
-	/* maybe allocate device-global string ID */
-	if (gser_string_defs[0].id == 0) {
-		status = usb_string_id(c->cdev);
-		if (status < 0)
-			return status;
-		gser_string_defs[0].id = status;
-	}
-
 	/* allocate and initialize one new instance */
 	gser = kzalloc(sizeof *gser, GFP_KERNEL);
 	if (!gser)
@@ -288,7 +290,7 @@ int __init gser_bind_config(struct usb_configuration *c, u8 port_num)
 	gser->port.func.name = "gser";
 	gser->port.func.strings = gser_strings;
 	gser->port.func.bind = gser_bind;
-	gser->port.func.unbind = gser_unbind;
+	gser->port.func.unbind = gser_old_unbind;
 	gser->port.func.set_alt = gser_set_alt;
 	gser->port.func.disable = gser_disable;
 
@@ -297,3 +299,78 @@ int __init gser_bind_config(struct usb_configuration *c, u8 port_num)
 		kfree(gser);
 	return status;
 }
+
+#else
+
+static void gser_free_inst(struct usb_function_instance *f)
+{
+	struct f_serial_opts *opts;
+
+	opts = container_of(f, struct f_serial_opts, func_inst);
+	gserial_free_line(opts->port_num);
+	kfree(opts);
+}
+
+static struct usb_function_instance *gser_alloc_inst(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 = gser_free_inst;
+	ret = gserial_alloc_line(&opts->port_num);
+	if (ret) {
+		kfree(opts);
+		return ERR_PTR(ret);
+	}
+
+	return &opts->func_inst;
+}
+
+static void gser_free(struct usb_function *f)
+{
+	struct f_gser *serial;
+
+	serial = func_to_gser(f);
+	kfree(serial);
+}
+
+static void gser_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+	usb_free_all_descriptors(f);
+}
+
+struct usb_function *gser_alloc(struct usb_function_instance *fi)
+{
+	struct f_gser	*gser;
+	struct f_serial_opts *opts;
+
+	/* allocate and initialize one new instance */
+	gser = kzalloc(sizeof(*gser), GFP_KERNEL);
+	if (!gser)
+		return ERR_PTR(-ENOMEM);
+
+	opts = container_of(fi, struct f_serial_opts, func_inst);
+
+	gser->port_num = opts->port_num;
+
+	gser->port.func.name = "gser";
+	gser->port.func.strings = gser_strings;
+	gser->port.func.bind = gser_bind;
+	gser->port.func.unbind = gser_unbind;
+	gser->port.func.set_alt = gser_set_alt;
+	gser->port.func.disable = gser_disable;
+	gser->port.func.free_func = gser_free;
+
+	return &gser->port.func;
+}
+
+DECLARE_USB_FUNCTION_INIT(gser, gser_alloc_inst, gser_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Al Borchers");
+MODULE_AUTHOR("David Brownell");
+
+#endif

drivers/usb/gadget/serial.c

@@ -37,6 +37,7 @@
  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  */
 #include "f_obex.c"
+#define USB_FSERIAL_INCLUDED
 #include "f_serial.c"
 
 /*-------------------------------------------------------------------------*/