1 files changed, 486 insertions, 0 deletions
diff --git a/drivers/usb/gadget/g_ffs.c b/drivers/usb/gadget/g_ffs.c
new file mode 100644
index 00000000..787a78e9
--- /dev/null
+++ b/drivers/usb/gadget/g_ffs.c
@@ -0,0 +1,486 @@
+/*
+ * g_ffs.c -- user mode file system API for USB composite function controllers
+ *
+ * Copyright (C) 2010 Samsung Electronics
+ * Author: Michal Nazarewicz <mina86@mina86.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "g_ffs: " fmt
+
+#include <linux/module.h>
+/*
+ * kbuild is not very cooperative with respect to linking separately
+ * compiled library objects into one module.  So for now we won't use
+ * separate compilation ... ensuring init/exit sections work to shrink
+ * the runtime footprint, and giving us at least some parts of what
+ * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
+ */
+#if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
+#  if defined USB_ETH_RNDIS
+#    undef USB_ETH_RNDIS
+#  endif
+#  ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+#    define USB_ETH_RNDIS y
+#  endif
+
+#  include "f_ecm.c"
+#  include "f_subset.c"
+#  ifdef USB_ETH_RNDIS
+#    include "f_rndis.c"
+#    include "rndis.c"
+#  endif
+#  include "u_ether.c"
+
+static u8 gfs_hostaddr[ETH_ALEN];
+static struct eth_dev *the_dev;
+#  ifdef CONFIG_USB_FUNCTIONFS_ETH
+static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
+		struct eth_dev *dev);
+#  endif
+#else
+#  define the_dev	NULL
+#  define gether_cleanup(dev) do { } while (0)
+#  define gfs_hostaddr NULL
+struct eth_dev;
+#endif
+
+#include "f_fs.c"
+
+#define DRIVER_NAME	"g_ffs"
+#define DRIVER_DESC	"USB Function Filesystem"
+#define DRIVER_VERSION	"24 Aug 2004"
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Michal Nazarewicz");
+MODULE_LICENSE("GPL");
+
+#define GFS_VENDOR_ID	0x1d6b	/* Linux Foundation */
+#define GFS_PRODUCT_ID	0x0105	/* FunctionFS Gadget */
+
+#define GFS_MAX_DEVS	10
+
+struct gfs_ffs_obj {
+	const char *name;
+	bool mounted;
+	bool desc_ready;
+	struct ffs_data *ffs_data;
+};
+
+USB_GADGET_COMPOSITE_OPTIONS();
+
+static struct usb_device_descriptor gfs_dev_desc = {
+	.bLength		= sizeof gfs_dev_desc,
+	.bDescriptorType	= USB_DT_DEVICE,
+
+	.bcdUSB			= cpu_to_le16(0x0200),
+	.bDeviceClass		= USB_CLASS_PER_INTERFACE,
+
+	.idVendor		= cpu_to_le16(GFS_VENDOR_ID),
+	.idProduct		= cpu_to_le16(GFS_PRODUCT_ID),
+};
+
+static char *func_names[GFS_MAX_DEVS];
+static unsigned int func_num;
+
+module_param_named(bDeviceClass,    gfs_dev_desc.bDeviceClass,    byte,   0644);
+MODULE_PARM_DESC(bDeviceClass, "USB Device class");
+module_param_named(bDeviceSubClass, gfs_dev_desc.bDeviceSubClass, byte,   0644);
+MODULE_PARM_DESC(bDeviceSubClass, "USB Device subclass");
+module_param_named(bDeviceProtocol, gfs_dev_desc.bDeviceProtocol, byte,   0644);
+MODULE_PARM_DESC(bDeviceProtocol, "USB Device protocol");
+module_param_array_named(functions, func_names, charp, &func_num, 0);
+MODULE_PARM_DESC(functions, "USB Functions list");
+
+static const struct usb_descriptor_header *gfs_otg_desc[] = {
+	(const struct usb_descriptor_header *)
+	&(const struct usb_otg_descriptor) {
+		.bLength		= sizeof(struct usb_otg_descriptor),
+		.bDescriptorType	= USB_DT_OTG,
+
+		/*
+		 * REVISIT SRP-only hardware is possible, although
+		 * it would not be called "OTG" ...
+		 */
+		.bmAttributes		= USB_OTG_SRP | USB_OTG_HNP,
+	},
+
+	NULL
+};
+
+/* String IDs are assigned dynamically */
+static struct usb_string gfs_strings[] = {
+	[USB_GADGET_MANUFACTURER_IDX].s = "",
+	[USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
+	[USB_GADGET_SERIAL_IDX].s = "",
+#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+	{ .s = "FunctionFS + RNDIS" },
+#endif
+#ifdef CONFIG_USB_FUNCTIONFS_ETH
+	{ .s = "FunctionFS + ECM" },
+#endif
+#ifdef CONFIG_USB_FUNCTIONFS_GENERIC
+	{ .s = "FunctionFS" },
+#endif
+	{  } /* end of list */
+};
+
+static struct usb_gadget_strings *gfs_dev_strings[] = {
+	&(struct usb_gadget_strings) {
+		.language	= 0x0409,	/* en-us */
+		.strings	= gfs_strings,
+	},
+	NULL,
+};
+
+struct gfs_configuration {
+	struct usb_configuration c;
+	int (*eth)(struct usb_configuration *c, u8 *ethaddr,
+			struct eth_dev *dev);
+} gfs_configurations[] = {
+#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+	{
+		.eth		= rndis_bind_config,
+	},
+#endif
+
+#ifdef CONFIG_USB_FUNCTIONFS_ETH
+	{
+		.eth		= eth_bind_config,
+	},
+#endif
+
+#ifdef CONFIG_USB_FUNCTIONFS_GENERIC
+	{
+	},
+#endif
+};
+
+static int gfs_bind(struct usb_composite_dev *cdev);
+static int gfs_unbind(struct usb_composite_dev *cdev);
+static int gfs_do_config(struct usb_configuration *c);
+
+static __refdata struct usb_composite_driver gfs_driver = {
+	.name		= DRIVER_NAME,
+	.dev		= &gfs_dev_desc,
+	.strings	= gfs_dev_strings,
+	.max_speed	= USB_SPEED_HIGH,
+	.bind		= gfs_bind,
+	.unbind		= gfs_unbind,
+};
+
+static DEFINE_MUTEX(gfs_lock);
+static unsigned int missing_funcs;
+static bool gfs_ether_setup;
+static bool gfs_registered;
+static bool gfs_single_func;
+static struct gfs_ffs_obj *ffs_tab;
+
+static int __init gfs_init(void)
+{
+	int i;
+
+	ENTER();
+
+	if (!func_num) {
+		gfs_single_func = true;
+		func_num = 1;
+	}
+
+	ffs_tab = kcalloc(func_num, sizeof *ffs_tab, GFP_KERNEL);
+	if (!ffs_tab)
+		return -ENOMEM;
+
+	if (!gfs_single_func)
+		for (i = 0; i < func_num; i++)
+			ffs_tab[i].name = func_names[i];
+
+	missing_funcs = func_num;
+
+	return functionfs_init();
+}
+module_init(gfs_init);
+
+static void __exit gfs_exit(void)
+{
+	ENTER();
+	mutex_lock(&gfs_lock);
+
+	if (gfs_registered)
+		usb_composite_unregister(&gfs_driver);
+	gfs_registered = false;
+
+	functionfs_cleanup();
+
+	mutex_unlock(&gfs_lock);
+	kfree(ffs_tab);
+}
+module_exit(gfs_exit);
+
+static struct gfs_ffs_obj *gfs_find_dev(const char *dev_name)
+{
+	int i;
+
+	ENTER();
+
+	if (gfs_single_func)
+		return &ffs_tab[0];
+
+	for (i = 0; i < func_num; i++)
+		if (strcmp(ffs_tab[i].name, dev_name) == 0)
+			return &ffs_tab[i];
+
+	return NULL;
+}
+
+static int functionfs_ready_callback(struct ffs_data *ffs)
+{
+	struct gfs_ffs_obj *ffs_obj;
+	int ret;
+
+	ENTER();
+	mutex_lock(&gfs_lock);
+
+	ffs_obj = ffs->private_data;
+	if (!ffs_obj) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	if (WARN_ON(ffs_obj->desc_ready)) {
+		ret = -EBUSY;
+		goto done;
+	}
+	ffs_obj->desc_ready = true;
+	ffs_obj->ffs_data = ffs;
+
+	if (--missing_funcs) {
+		ret = 0;
+		goto done;
+	}
+
+	if (gfs_registered) {
+		ret = -EBUSY;
+		goto done;
+	}
+	gfs_registered = true;
+
+	ret = usb_composite_probe(&gfs_driver);
+	if (unlikely(ret < 0))
+		gfs_registered = false;
+
+done:
+	mutex_unlock(&gfs_lock);
+	return ret;
+}
+
+static void functionfs_closed_callback(struct ffs_data *ffs)
+{
+	struct gfs_ffs_obj *ffs_obj;
+
+	ENTER();
+	mutex_lock(&gfs_lock);
+
+	ffs_obj = ffs->private_data;
+	if (!ffs_obj)
+		goto done;
+
+	ffs_obj->desc_ready = false;
+	missing_funcs++;
+
+	if (gfs_registered)
+		usb_composite_unregister(&gfs_driver);
+	gfs_registered = false;
+
+done:
+	mutex_unlock(&gfs_lock);
+}
+
+static void *functionfs_acquire_dev_callback(const char *dev_name)
+{
+	struct gfs_ffs_obj *ffs_dev;
+
+	ENTER();
+	mutex_lock(&gfs_lock);
+
+	ffs_dev = gfs_find_dev(dev_name);
+	if (!ffs_dev) {
+		ffs_dev = ERR_PTR(-ENODEV);
+		goto done;
+	}
+
+	if (ffs_dev->mounted) {
+		ffs_dev = ERR_PTR(-EBUSY);
+		goto done;
+	}
+	ffs_dev->mounted = true;
+
+done:
+	mutex_unlock(&gfs_lock);
+	return ffs_dev;
+}
+
+static void functionfs_release_dev_callback(struct ffs_data *ffs_data)
+{
+	struct gfs_ffs_obj *ffs_dev;
+
+	ENTER();
+	mutex_lock(&gfs_lock);
+
+	ffs_dev = ffs_data->private_data;
+	if (ffs_dev)
+		ffs_dev->mounted = false;
+
+	mutex_unlock(&gfs_lock);
+}
+
+/*
+ * It is assumed that gfs_bind is called from a context where gfs_lock is held
+ */
+static int gfs_bind(struct usb_composite_dev *cdev)
+{
+	int ret, i;
+
+	ENTER();
+
+	if (missing_funcs)
+		return -ENODEV;
+#if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
+	the_dev = gether_setup(cdev->gadget, gfs_hostaddr);
+#endif
+	if (IS_ERR(the_dev)) {
+		ret = PTR_ERR(the_dev);
+		goto error_quick;
+	}
+	gfs_ether_setup = true;
+
+	ret = usb_string_ids_tab(cdev, gfs_strings);
+	if (unlikely(ret < 0))
+		goto error;
+	gfs_dev_desc.iProduct = gfs_strings[USB_GADGET_PRODUCT_IDX].id;
+
+	for (i = func_num; i--; ) {
+		ret = functionfs_bind(ffs_tab[i].ffs_data, cdev);
+		if (unlikely(ret < 0)) {
+			while (++i < func_num)
+				functionfs_unbind(ffs_tab[i].ffs_data);
+			goto error;
+		}
+	}
+
+	for (i = 0; i < ARRAY_SIZE(gfs_configurations); ++i) {
+		struct gfs_configuration *c = gfs_configurations + i;
+		int sid = USB_GADGET_FIRST_AVAIL_IDX + i;
+
+		c->c.label			= gfs_strings[sid].s;
+		c->c.iConfiguration		= gfs_strings[sid].id;
+		c->c.bConfigurationValue	= 1 + i;
+		c->c.bmAttributes		= USB_CONFIG_ATT_SELFPOWER;
+
+		ret = usb_add_config(cdev, &c->c, gfs_do_config);
+		if (unlikely(ret < 0))
+			goto error_unbind;
+	}
+	usb_composite_overwrite_options(cdev, &coverwrite);
+	return 0;
+
+error_unbind:
+	for (i = 0; i < func_num; i++)
+		functionfs_unbind(ffs_tab[i].ffs_data);
+error:
+	gether_cleanup(the_dev);
+error_quick:
+	gfs_ether_setup = false;
+	return ret;
+}
+
+/*
+ * It is assumed that gfs_unbind is called from a context where gfs_lock is held
+ */
+static int gfs_unbind(struct usb_composite_dev *cdev)
+{
+	int i;
+
+	ENTER();
+
+	/*
+	 * We may have been called in an error recovery from
+	 * composite_bind() after gfs_unbind() failure so we need to
+	 * check if gfs_ffs_data is not NULL since gfs_bind() handles
+	 * all error recovery itself.  I'd rather we werent called
+	 * from composite on orror recovery, but what you're gonna
+	 * do...?
+	 */
+	if (gfs_ether_setup)
+		gether_cleanup(the_dev);
+	gfs_ether_setup = false;
+
+	for (i = func_num; i--; )
+		if (ffs_tab[i].ffs_data)
+			functionfs_unbind(ffs_tab[i].ffs_data);
+
+	return 0;
+}
+
+/*
+ * It is assumed that gfs_do_config is called from a context where
+ * gfs_lock is held
+ */
+static int gfs_do_config(struct usb_configuration *c)
+{
+	struct gfs_configuration *gc =
+		container_of(c, struct gfs_configuration, c);
+	int i;
+	int ret;
+
+	if (missing_funcs)
+		return -ENODEV;
+
+	if (gadget_is_otg(c->cdev->gadget)) {
+		c->descriptors = gfs_otg_desc;
+		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
+	}
+
+	if (gc->eth) {
+		ret = gc->eth(c, gfs_hostaddr, the_dev);
+		if (unlikely(ret < 0))
+			return ret;
+	}
+
+	for (i = 0; i < func_num; i++) {
+		ret = functionfs_bind_config(c->cdev, c, ffs_tab[i].ffs_data);
+		if (unlikely(ret < 0))
+			return ret;
+	}
+
+	/*
+	 * After previous do_configs there may be some invalid
+	 * pointers in c->interface array.  This happens every time
+	 * a user space function with fewer interfaces than a user
+	 * space function that was run before the new one is run.  The
+	 * compasit's set_config() assumes that if there is no more
+	 * then MAX_CONFIG_INTERFACES interfaces in a configuration
+	 * then there is a NULL pointer after the last interface in
+	 * c->interface array.  We need to make sure this is true.
+	 */
+	if (c->next_interface_id < ARRAY_SIZE(c->interface))
+		c->interface[c->next_interface_id] = NULL;
+
+	return 0;
+}
+
+#ifdef CONFIG_USB_FUNCTIONFS_ETH
+
+static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
+		struct eth_dev *dev)
+{
+	return can_support_ecm(c->cdev->gadget)
+		? ecm_bind_config(c, ethaddr, dev)
+		: geth_bind_config(c, ethaddr, dev);
+}
+
+#endif