usb: gadget: convert source sink and loopback to new function interface

This patch converts the f_sourcesink and f_loopback file to the USB-function
module. Both functions shares a few common utility functions which are
currently implemented in g_zero.c itself. This patch moves the common
code into the sourcesink file and creates one module out of the the two
functions (source sink and loop back).
The g_zero gadget is function specific to source sink and loop back to
set a few options. This Symbol dependency enforces a modul load right
now.

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

1 files changed, 56 insertions, 19 deletions

diff --git a/drivers/usb/gadget/f_loopback.c b/drivers/usb/gadget/f_loopback.c
index 3d103a2f998f..4a3873a0f2d0 100644
--- a/drivers/usb/gadget/f_loopback.c
+++ b/drivers/usb/gadget/f_loopback.c
@@ -15,10 +15,11 @@
 #include <linux/slab.h>
 #include <linux/kernel.h>
 #include <linux/device.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/usb/composite.h>
 
 #include "g_zero.h"
-#include "gadget_chips.h"
-
 
 /*
  * LOOPBACK FUNCTION ... a testing vehicle for USB peripherals,
@@ -44,9 +45,8 @@ static inline struct f_loopback *func_to_loop(struct usb_function *f)
         return container_of(f, struct f_loopback, function);
 }
 
-static unsigned qlen = 32;
-module_param(qlen, uint, 0);
-MODULE_PARM_DESC(qlenn, "depth of loopback queue");
+static unsigned qlen;
+static unsigned buflen;
 
 /*-------------------------------------------------------------------------*/
 
@@ -171,8 +171,7 @@ static struct usb_gadget_strings *loopback_strings[] = {
 
 /*-------------------------------------------------------------------------*/
 
-static int __init
-loopback_bind(struct usb_configuration *c, struct usb_function *f)
+static int loopback_bind(struct usb_configuration *c, struct usb_function *f)
 {
         struct usb_composite_dev *cdev = c->cdev;
         struct f_loopback       *loop = func_to_loop(f);
@@ -229,8 +228,7 @@ autoconf_fail:
         return 0;
 }
 
-static void
-loopback_unbind(struct usb_configuration *c, struct usb_function *f)
+static void lb_free_func(struct usb_function *f)
 {
         usb_free_all_descriptors(f);
         kfree(func_to_loop(f));
@@ -372,25 +370,64 @@ static void loopback_disable(struct usb_function *f)
         disable_loopback(loop);
 }
 
-/*-------------------------------------------------------------------------*/
-
-static int __init loopback_bind_config(struct usb_configuration *c)
+static struct usb_function *loopback_alloc(struct usb_function_instance *fi)
 {
         struct f_loopback       *loop;
-        int                     status;
+        struct f_lb_opts        *lb_opts;
 
         loop = kzalloc(sizeof *loop, GFP_KERNEL);
         if (!loop)
-                return -ENOMEM;
+                return ERR_PTR(-ENOMEM);
+
+        lb_opts = container_of(fi, struct f_lb_opts, func_inst);
+        buflen = lb_opts->bulk_buflen;
+        qlen = lb_opts->qlen;
+        if (!qlen)
+                qlen = 32;
 
         loop->function.name = "loopback";
         loop->function.bind = loopback_bind;
-        loop->function.unbind = loopback_unbind;
         loop->function.set_alt = loopback_set_alt;
         loop->function.disable = loopback_disable;
+        loop->function.strings = loopback_strings;
+
+        loop->function.free_func = lb_free_func;
+
+        return &loop->function;
+}
+
+static void lb_free_instance(struct usb_function_instance *fi)
+{
+        struct f_lb_opts *lb_opts;
 
-        status = usb_add_function(c, &loop->function);
-        if (status)
-                kfree(loop);
-        return status;
+        lb_opts = container_of(fi, struct f_lb_opts, func_inst);
+        kfree(lb_opts);
 }
+
+static struct usb_function_instance *loopback_alloc_instance(void)
+{
+        struct f_lb_opts *lb_opts;
+
+        lb_opts = kzalloc(sizeof(*lb_opts), GFP_KERNEL);
+        if (!lb_opts)
+                return ERR_PTR(-ENOMEM);
+        lb_opts->func_inst.free_func_inst = lb_free_instance;
+        return  &lb_opts->func_inst;
+}
+DECLARE_USB_FUNCTION(Loopback, loopback_alloc_instance, loopback_alloc);
+
+int __init lb_modinit(void)
+{
+        int ret;
+
+        ret = usb_function_register(&Loopbackusb_func);
+        if (ret)
+                return ret;
+        return ret;
+}
+void __exit lb_modexit(void)
+{
+        usb_function_unregister(&Loopbackusb_func);
+}
+
+MODULE_LICENSE("GPL");