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

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

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

The file is now compiled into a separate usb_f_eem.ko module.

The old function interface is provided by means of a 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>

1 files changed, 138 insertions, 36 deletions

diff --git a/drivers/usb/gadget/f_eem.c b/drivers/usb/gadget/f_eem.c
index f4e0bbef602a..471acc824115 100644
--- a/drivers/usb/gadget/f_eem.c
+++ b/drivers/usb/gadget/f_eem.c
@@ -12,12 +12,14 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/device.h>
 #include <linux/etherdevice.h>
 #include <linux/crc32.h>
 #include <linux/slab.h>
 
 #include "u_ether.h"
+#include "u_eem.h"
 
 #define EEM_HLEN 2
 
@@ -40,7 +42,7 @@ static inline struct f_eem *func_to_eem(struct usb_function *f)
 
 /* interface descriptor: */
 
-static struct usb_interface_descriptor eem_intf __initdata = {
+static struct usb_interface_descriptor eem_intf = {
         .bLength =              sizeof eem_intf,
         .bDescriptorType =      USB_DT_INTERFACE,
 
@@ -54,7 +56,7 @@ static struct usb_interface_descriptor eem_intf __initdata = {
 
 /* full speed support: */
 
-static struct usb_endpoint_descriptor eem_fs_in_desc __initdata = {
+static struct usb_endpoint_descriptor eem_fs_in_desc = {
         .bLength =              USB_DT_ENDPOINT_SIZE,
         .bDescriptorType =      USB_DT_ENDPOINT,
 
@@ -62,7 +64,7 @@ static struct usb_endpoint_descriptor eem_fs_in_desc __initdata = {
         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 };
 
-static struct usb_endpoint_descriptor eem_fs_out_desc __initdata = {
+static struct usb_endpoint_descriptor eem_fs_out_desc = {
         .bLength =              USB_DT_ENDPOINT_SIZE,
         .bDescriptorType =      USB_DT_ENDPOINT,
 
@@ -70,7 +72,7 @@ static struct usb_endpoint_descriptor eem_fs_out_desc __initdata = {
         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 };
 
-static struct usb_descriptor_header *eem_fs_function[] __initdata = {
+static struct usb_descriptor_header *eem_fs_function[] = {
         /* CDC EEM control descriptors */
         (struct usb_descriptor_header *) &eem_intf,
         (struct usb_descriptor_header *) &eem_fs_in_desc,
@@ -80,7 +82,7 @@ static struct usb_descriptor_header *eem_fs_function[] __initdata = {
 
 /* high speed support: */
 
-static struct usb_endpoint_descriptor eem_hs_in_desc __initdata = {
+static struct usb_endpoint_descriptor eem_hs_in_desc = {
         .bLength =              USB_DT_ENDPOINT_SIZE,
         .bDescriptorType =      USB_DT_ENDPOINT,
 
@@ -89,7 +91,7 @@ static struct usb_endpoint_descriptor eem_hs_in_desc __initdata = {
         .wMaxPacketSize =       cpu_to_le16(512),
 };
 
-static struct usb_endpoint_descriptor eem_hs_out_desc __initdata = {
+static struct usb_endpoint_descriptor eem_hs_out_desc = {
         .bLength =              USB_DT_ENDPOINT_SIZE,
         .bDescriptorType =      USB_DT_ENDPOINT,
 
@@ -98,7 +100,7 @@ static struct usb_endpoint_descriptor eem_hs_out_desc __initdata = {
         .wMaxPacketSize =       cpu_to_le16(512),
 };
 
-static struct usb_descriptor_header *eem_hs_function[] __initdata = {
+static struct usb_descriptor_header *eem_hs_function[] = {
         /* CDC EEM control descriptors */
         (struct usb_descriptor_header *) &eem_intf,
         (struct usb_descriptor_header *) &eem_hs_in_desc,
@@ -108,7 +110,7 @@ static struct usb_descriptor_header *eem_hs_function[] __initdata = {
 
 /* super speed support: */
 
-static struct usb_endpoint_descriptor eem_ss_in_desc __initdata = {
+static struct usb_endpoint_descriptor eem_ss_in_desc = {
         .bLength =              USB_DT_ENDPOINT_SIZE,
         .bDescriptorType =      USB_DT_ENDPOINT,
 
@@ -117,7 +119,7 @@ static struct usb_endpoint_descriptor eem_ss_in_desc __initdata = {
         .wMaxPacketSize =       cpu_to_le16(1024),
 };
 
-static struct usb_endpoint_descriptor eem_ss_out_desc __initdata = {
+static struct usb_endpoint_descriptor eem_ss_out_desc = {
         .bLength =              USB_DT_ENDPOINT_SIZE,
         .bDescriptorType =      USB_DT_ENDPOINT,
 
@@ -126,7 +128,7 @@ static struct usb_endpoint_descriptor eem_ss_out_desc __initdata = {
         .wMaxPacketSize =       cpu_to_le16(1024),
 };
 
-static struct usb_ss_ep_comp_descriptor eem_ss_bulk_comp_desc __initdata = {
+static struct usb_ss_ep_comp_descriptor eem_ss_bulk_comp_desc = {
         .bLength =              sizeof eem_ss_bulk_comp_desc,
         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 
@@ -135,7 +137,7 @@ static struct usb_ss_ep_comp_descriptor eem_ss_bulk_comp_desc __initdata = {
         /* .bmAttributes =      0, */
 };
 
-static struct usb_descriptor_header *eem_ss_function[] __initdata = {
+static struct usb_descriptor_header *eem_ss_function[] = {
         /* CDC EEM control descriptors */
         (struct usb_descriptor_header *) &eem_intf,
         (struct usb_descriptor_header *) &eem_ss_in_desc,
@@ -242,14 +244,44 @@ static void eem_disable(struct usb_function *f)
 
 /* EEM function driver setup/binding */
 
-static int __init
-eem_bind(struct usb_configuration *c, struct usb_function *f)
+static int eem_bind(struct usb_configuration *c, struct usb_function *f)
 {
         struct usb_composite_dev *cdev = c->cdev;
         struct f_eem            *eem = func_to_eem(f);
         int                     status;
         struct usb_ep           *ep;
 
+#ifndef USB_FEEM_INCLUDED
+        struct f_eem_opts       *eem_opts;
+
+        eem_opts = container_of(f->fi, struct f_eem_opts, func_inst);
+        /*
+         * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
+         * configurations are bound in sequence with list_for_each_entry,
+         * in each configuration its functions are bound in sequence
+         * with list_for_each_entry, so we assume no race condition
+         * with regard to eem_opts->bound access
+         */
+        if (!eem_opts->bound) {
+                gether_set_gadget(eem_opts->net, cdev->gadget);
+                status = gether_register_netdev(eem_opts->net);
+                if (status)
+                        return status;
+                eem_opts->bound = true;
+        }
+#endif
+
+        /* maybe allocate device-global string IDs */
+        if (eem_string_defs[0].id == 0) {
+
+                /* control interface label */
+                status = usb_string_id(c->cdev);
+                if (status < 0)
+                        return status;
+                eem_string_defs[0].id = status;
+                eem_intf.iInterface = status;
+        }
+
         /* allocate instance-specific interface IDs */
         status = usb_interface_id(c, f);
         if (status < 0)
@@ -307,17 +339,6 @@ fail:
         return status;
 }
 
-static void
-eem_unbind(struct usb_configuration *c, struct usb_function *f)
-{
-        struct f_eem    *eem = func_to_eem(f);
-
-        DBG(c->cdev, "eem unbind\n");
-
-        usb_free_all_descriptors(f);
-        kfree(eem);
-}
-
 static void eem_cmd_complete(struct usb_ep *ep, struct usb_request *req)
 {
         struct sk_buff *skb = (struct sk_buff *)req->context;
@@ -518,6 +539,18 @@ error:
         return status;
 }
 
+#ifdef USB_FEEM_INCLUDED
+
+static void eem_old_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+        struct f_eem    *eem = func_to_eem(f);
+
+        DBG(c->cdev, "eem unbind\n");
+
+        usb_free_all_descriptors(f);
+        kfree(eem);
+}
+
 /**
  * eem_bind_config - add CDC Ethernet (EEM) network link to a configuration
  * @c: the configuration to support the network link
@@ -533,17 +566,6 @@ int __init eem_bind_config(struct usb_configuration *c, struct eth_dev *dev)
         struct f_eem    *eem;
         int             status;
 
-        /* maybe allocate device-global string IDs */
-        if (eem_string_defs[0].id == 0) {
-
-                /* control interface label */
-                status = usb_string_id(c->cdev);
-                if (status < 0)
-                        return status;
-                eem_string_defs[0].id = status;
-                eem_intf.iInterface = status;
-        }
-
         /* allocate and initialize one new instance */
         eem = kzalloc(sizeof *eem, GFP_KERNEL);
         if (!eem)
@@ -556,7 +578,7 @@ int __init eem_bind_config(struct usb_configuration *c, struct eth_dev *dev)
         eem->port.func.strings = eem_strings;
         /* descriptors are per-instance copies */
         eem->port.func.bind = eem_bind;
-        eem->port.func.unbind = eem_unbind;
+        eem->port.func.unbind = eem_old_unbind;
         eem->port.func.set_alt = eem_set_alt;
         eem->port.func.setup = eem_setup;
         eem->port.func.disable = eem_disable;
@@ -570,3 +592,83 @@ int __init eem_bind_config(struct usb_configuration *c, struct eth_dev *dev)
         return status;
 }
 
+#else
+
+static void eem_free_inst(struct usb_function_instance *f)
+{
+        struct f_eem_opts *opts;
+
+        opts = container_of(f, struct f_eem_opts, func_inst);
+        if (opts->bound)
+                gether_cleanup(netdev_priv(opts->net));
+        else
+                free_netdev(opts->net);
+        kfree(opts);
+}
+
+static struct usb_function_instance *eem_alloc_inst(void)
+{
+        struct f_eem_opts *opts;
+
+        opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+        if (!opts)
+                return ERR_PTR(-ENOMEM);
+        opts->func_inst.free_func_inst = eem_free_inst;
+        opts->net = gether_setup_default();
+        if (IS_ERR(opts->net))
+                return ERR_CAST(opts->net);
+
+        return &opts->func_inst;
+}
+
+static void eem_free(struct usb_function *f)
+{
+        struct f_eem *eem;
+
+        eem = func_to_eem(f);
+        kfree(eem);
+}
+
+static void eem_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+        DBG(c->cdev, "eem unbind\n");
+
+        usb_free_all_descriptors(f);
+}
+
+struct usb_function *eem_alloc(struct usb_function_instance *fi)
+{
+        struct f_eem    *eem;
+        struct f_eem_opts *opts;
+
+        /* allocate and initialize one new instance */
+        eem = kzalloc(sizeof(*eem), GFP_KERNEL);
+        if (!eem)
+                return ERR_PTR(-ENOMEM);
+
+        opts = container_of(fi, struct f_eem_opts, func_inst);
+
+        eem->port.ioport = netdev_priv(opts->net);
+        eem->port.cdc_filter = DEFAULT_FILTER;
+
+        eem->port.func.name = "cdc_eem";
+        eem->port.func.strings = eem_strings;
+        /* descriptors are per-instance copies */
+        eem->port.func.bind = eem_bind;
+        eem->port.func.unbind = eem_unbind;
+        eem->port.func.set_alt = eem_set_alt;
+        eem->port.func.setup = eem_setup;
+        eem->port.func.disable = eem_disable;
+        eem->port.func.free_func = eem_free;
+        eem->port.wrap = eem_wrap;
+        eem->port.unwrap = eem_unwrap;
+        eem->port.header_len = EEM_HLEN;
+
+        return &eem->port.func;
+}
+
+DECLARE_USB_FUNCTION_INIT(eem, eem_alloc_inst, eem_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Brownell");
+
+#endif