1 files changed, 581 insertions, 0 deletions
diff --git a/drivers/usb/gadget/legacy/g_ffs.c b/drivers/usb/gadget/legacy/g_ffs.c
new file mode 100644
index 000000000..ae6d8f709
--- /dev/null
+++ b/drivers/usb/gadget/legacy/g_ffs.c
@@ -0,0 +1,581 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * g_ffs.c -- user mode file system API for USB composite function controllers
+ *
+ * Copyright (C) 2010 Samsung Electronics
+ * Author: Michal Nazarewicz <mina86@mina86.com>
+ */
+
+#define pr_fmt(fmt) "g_ffs: " fmt
+
+#include <linux/module.h>
+
+#if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
+#include <linux/netdevice.h>
+
+#  if defined USB_ETH_RNDIS
+#    undef USB_ETH_RNDIS
+#  endif
+#  ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+#    define USB_ETH_RNDIS y
+#  endif
+
+#  include "u_ecm.h"
+#  include "u_gether.h"
+#  ifdef USB_ETH_RNDIS
+#    include "u_rndis.h"
+#    include "rndis.h"
+#  endif
+#  include "u_ether.h"
+
+USB_ETHERNET_MODULE_PARAMETERS();
+
+#  ifdef CONFIG_USB_FUNCTIONFS_ETH
+static int eth_bind_config(struct usb_configuration *c);
+static struct usb_function_instance *fi_ecm;
+static struct usb_function *f_ecm;
+static struct usb_function_instance *fi_geth;
+static struct usb_function *f_geth;
+#  endif
+#  ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+static int bind_rndis_config(struct usb_configuration *c);
+static struct usb_function_instance *fi_rndis;
+static struct usb_function *f_rndis;
+#  endif
+#endif
+
+#include "u_fs.h"
+
+#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
+
+USB_GADGET_COMPOSITE_OPTIONS();
+
+static struct usb_device_descriptor gfs_dev_desc = {
+	.bLength		= sizeof gfs_dev_desc,
+	.bDescriptorType	= USB_DT_DEVICE,
+
+	/* .bcdUSB = DYNAMIC */
+	.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[2];
+
+/* 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);
+	int num;
+};
+
+static struct gfs_configuration gfs_configurations[] = {
+#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+	{
+		.eth		= bind_rndis_config,
+	},
+#endif
+
+#ifdef CONFIG_USB_FUNCTIONFS_ETH
+	{
+		.eth		= eth_bind_config,
+	},
+#endif
+
+#ifdef CONFIG_USB_FUNCTIONFS_GENERIC
+	{
+	},
+#endif
+};
+
+static void *functionfs_acquire_dev(struct ffs_dev *dev);
+static void functionfs_release_dev(struct ffs_dev *dev);
+static int functionfs_ready_callback(struct ffs_data *ffs);
+static void functionfs_closed_callback(struct ffs_data *ffs);
+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 struct usb_composite_driver gfs_driver = {
+	.name		= DRIVER_NAME,
+	.dev		= &gfs_dev_desc,
+	.strings	= gfs_dev_strings,
+	.max_speed	= USB_SPEED_SUPER,
+	.bind		= gfs_bind,
+	.unbind		= gfs_unbind,
+};
+
+static unsigned int missing_funcs;
+static bool gfs_registered;
+static bool gfs_single_func;
+static struct usb_function_instance **fi_ffs;
+static struct usb_function **f_ffs[] = {
+#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+	NULL,
+#endif
+
+#ifdef CONFIG_USB_FUNCTIONFS_ETH
+	NULL,
+#endif
+
+#ifdef CONFIG_USB_FUNCTIONFS_GENERIC
+	NULL,
+#endif
+};
+
+#define N_CONF ARRAY_SIZE(f_ffs)
+
+static int __init gfs_init(void)
+{
+	struct f_fs_opts *opts;
+	int i;
+	int ret = 0;
+
+	ENTER();
+
+	if (func_num < 2) {
+		gfs_single_func = true;
+		func_num = 1;
+	}
+
+	/*
+	 * Allocate in one chunk for easier maintenance
+	 */
+	f_ffs[0] = kcalloc(func_num * N_CONF, sizeof(*f_ffs), GFP_KERNEL);
+	if (!f_ffs[0]) {
+		ret = -ENOMEM;
+		goto no_func;
+	}
+	for (i = 1; i < N_CONF; ++i)
+		f_ffs[i] = f_ffs[0] + i * func_num;
+
+	fi_ffs = kcalloc(func_num, sizeof(*fi_ffs), GFP_KERNEL);
+	if (!fi_ffs) {
+		ret = -ENOMEM;
+		goto no_func;
+	}
+
+	for (i = 0; i < func_num; i++) {
+		fi_ffs[i] = usb_get_function_instance("ffs");
+		if (IS_ERR(fi_ffs[i])) {
+			ret = PTR_ERR(fi_ffs[i]);
+			--i;
+			goto no_dev;
+		}
+		opts = to_f_fs_opts(fi_ffs[i]);
+		if (gfs_single_func)
+			ret = ffs_single_dev(opts->dev);
+		else
+			ret = ffs_name_dev(opts->dev, func_names[i]);
+		if (ret)
+			goto no_dev;
+		opts->dev->ffs_ready_callback = functionfs_ready_callback;
+		opts->dev->ffs_closed_callback = functionfs_closed_callback;
+		opts->dev->ffs_acquire_dev_callback = functionfs_acquire_dev;
+		opts->dev->ffs_release_dev_callback = functionfs_release_dev;
+		opts->no_configfs = true;
+	}
+
+	missing_funcs = func_num;
+
+	return 0;
+no_dev:
+	while (i >= 0)
+		usb_put_function_instance(fi_ffs[i--]);
+	kfree(fi_ffs);
+no_func:
+	kfree(f_ffs[0]);
+	return ret;
+}
+module_init(gfs_init);
+
+static void __exit gfs_exit(void)
+{
+	int i;
+
+	ENTER();
+
+	if (gfs_registered)
+		usb_composite_unregister(&gfs_driver);
+	gfs_registered = false;
+
+	kfree(f_ffs[0]);
+
+	for (i = 0; i < func_num; i++)
+		usb_put_function_instance(fi_ffs[i]);
+
+	kfree(fi_ffs);
+}
+module_exit(gfs_exit);
+
+static void *functionfs_acquire_dev(struct ffs_dev *dev)
+{
+	if (!try_module_get(THIS_MODULE))
+		return ERR_PTR(-ENOENT);
+
+	return NULL;
+}
+
+static void functionfs_release_dev(struct ffs_dev *dev)
+{
+	module_put(THIS_MODULE);
+}
+
+/*
+ * The caller of this function takes ffs_lock
+ */
+static int functionfs_ready_callback(struct ffs_data *ffs)
+{
+	int ret = 0;
+
+	if (--missing_funcs)
+		return 0;
+
+	if (gfs_registered)
+		return -EBUSY;
+
+	gfs_registered = true;
+
+	ret = usb_composite_probe(&gfs_driver);
+	if (unlikely(ret < 0)) {
+		++missing_funcs;
+		gfs_registered = false;
+	}
+
+	return ret;
+}
+
+/*
+ * The caller of this function takes ffs_lock
+ */
+static void functionfs_closed_callback(struct ffs_data *ffs)
+{
+	missing_funcs++;
+
+	if (gfs_registered)
+		usb_composite_unregister(&gfs_driver);
+	gfs_registered = false;
+}
+
+/*
+ * It is assumed that gfs_bind is called from a context where ffs_lock is held
+ */
+static int gfs_bind(struct usb_composite_dev *cdev)
+{
+#if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
+	struct net_device *net;
+#endif
+	int ret, i;
+
+	ENTER();
+
+	if (missing_funcs)
+		return -ENODEV;
+#if defined CONFIG_USB_FUNCTIONFS_ETH
+	if (can_support_ecm(cdev->gadget)) {
+		struct f_ecm_opts *ecm_opts;
+
+		fi_ecm = usb_get_function_instance("ecm");
+		if (IS_ERR(fi_ecm))
+			return PTR_ERR(fi_ecm);
+		ecm_opts = container_of(fi_ecm, struct f_ecm_opts, func_inst);
+		net = ecm_opts->net;
+	} else {
+		struct f_gether_opts *geth_opts;
+
+		fi_geth = usb_get_function_instance("geth");
+		if (IS_ERR(fi_geth))
+			return PTR_ERR(fi_geth);
+		geth_opts = container_of(fi_geth, struct f_gether_opts,
+					 func_inst);
+		net = geth_opts->net;
+	}
+#endif
+
+#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+	{
+		fi_rndis = usb_get_function_instance("rndis");
+		if (IS_ERR(fi_rndis)) {
+			ret = PTR_ERR(fi_rndis);
+			goto error;
+		}
+#ifndef CONFIG_USB_FUNCTIONFS_ETH
+		net = container_of(fi_rndis, struct f_rndis_opts,
+				   func_inst)->net;
+#endif
+	}
+#endif
+
+#if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
+	gether_set_qmult(net, qmult);
+	if (!gether_set_host_addr(net, host_addr))
+		pr_info("using host ethernet address: %s", host_addr);
+	if (!gether_set_dev_addr(net, dev_addr))
+		pr_info("using self ethernet address: %s", dev_addr);
+#endif
+
+#if defined CONFIG_USB_FUNCTIONFS_RNDIS && defined CONFIG_USB_FUNCTIONFS_ETH
+	gether_set_gadget(net, cdev->gadget);
+	ret = gether_register_netdev(net);
+	if (ret)
+		goto error_rndis;
+
+	if (can_support_ecm(cdev->gadget)) {
+		struct f_ecm_opts *ecm_opts;
+
+		ecm_opts = container_of(fi_ecm, struct f_ecm_opts, func_inst);
+		ecm_opts->bound = true;
+	} else {
+		struct f_gether_opts *geth_opts;
+
+		geth_opts = container_of(fi_geth, struct f_gether_opts,
+					 func_inst);
+		geth_opts->bound = true;
+	}
+
+	rndis_borrow_net(fi_rndis, net);
+#endif
+
+	/* TODO: gstrings_attach? */
+	ret = usb_string_ids_tab(cdev, gfs_strings);
+	if (unlikely(ret < 0))
+		goto error_rndis;
+	gfs_dev_desc.iProduct = gfs_strings[USB_GADGET_PRODUCT_IDX].id;
+
+	if (gadget_is_otg(cdev->gadget) && !gfs_otg_desc[0]) {
+		struct usb_descriptor_header *usb_desc;
+
+		usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
+		if (!usb_desc)
+			goto error_rndis;
+		usb_otg_descriptor_init(cdev->gadget, usb_desc);
+		gfs_otg_desc[0] = usb_desc;
+		gfs_otg_desc[1] = NULL;
+	}
+
+	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;
+
+		c->num = i;
+
+		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;
+
+/* TODO */
+error_unbind:
+	kfree(gfs_otg_desc[0]);
+	gfs_otg_desc[0] = NULL;
+error_rndis:
+#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+	usb_put_function_instance(fi_rndis);
+error:
+#endif
+#if defined CONFIG_USB_FUNCTIONFS_ETH
+	if (can_support_ecm(cdev->gadget))
+		usb_put_function_instance(fi_ecm);
+	else
+		usb_put_function_instance(fi_geth);
+#endif
+	return ret;
+}
+
+/*
+ * It is assumed that gfs_unbind is called from a context where ffs_lock is held
+ */
+static int gfs_unbind(struct usb_composite_dev *cdev)
+{
+	int i;
+
+	ENTER();
+
+
+#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+	usb_put_function(f_rndis);
+	usb_put_function_instance(fi_rndis);
+#endif
+
+#if defined CONFIG_USB_FUNCTIONFS_ETH
+	if (can_support_ecm(cdev->gadget)) {
+		usb_put_function(f_ecm);
+		usb_put_function_instance(fi_ecm);
+	} else {
+		usb_put_function(f_geth);
+		usb_put_function_instance(fi_geth);
+	}
+#endif
+	for (i = 0; i < N_CONF * func_num; ++i)
+		usb_put_function(*(f_ffs[0] + i));
+
+	kfree(gfs_otg_desc[0]);
+	gfs_otg_desc[0] = NULL;
+
+	return 0;
+}
+
+/*
+ * It is assumed that gfs_do_config is called from a context where
+ * ffs_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);
+		if (unlikely(ret < 0))
+			return ret;
+	}
+
+	for (i = 0; i < func_num; i++) {
+		f_ffs[gc->num][i] = usb_get_function(fi_ffs[i]);
+		if (IS_ERR(f_ffs[gc->num][i])) {
+			ret = PTR_ERR(f_ffs[gc->num][i]);
+			goto error;
+		}
+		ret = usb_add_function(c, f_ffs[gc->num][i]);
+		if (ret < 0) {
+			usb_put_function(f_ffs[gc->num][i]);
+			goto error;
+		}
+	}
+
+	/*
+	 * 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;
+error:
+	while (--i >= 0) {
+		if (!IS_ERR(f_ffs[gc->num][i]))
+			usb_remove_function(c, f_ffs[gc->num][i]);
+		usb_put_function(f_ffs[gc->num][i]);
+	}
+	return ret;
+}
+
+#ifdef CONFIG_USB_FUNCTIONFS_ETH
+
+static int eth_bind_config(struct usb_configuration *c)
+{
+	int status = 0;
+
+	if (can_support_ecm(c->cdev->gadget)) {
+		f_ecm = usb_get_function(fi_ecm);
+		if (IS_ERR(f_ecm))
+			return PTR_ERR(f_ecm);
+
+		status = usb_add_function(c, f_ecm);
+		if (status < 0)
+			usb_put_function(f_ecm);
+
+	} else {
+		f_geth = usb_get_function(fi_geth);
+		if (IS_ERR(f_geth))
+			return PTR_ERR(f_geth);
+
+		status = usb_add_function(c, f_geth);
+		if (status < 0)
+			usb_put_function(f_geth);
+	}
+	return status;
+}
+
+#endif
+
+#ifdef CONFIG_USB_FUNCTIONFS_RNDIS
+
+static int bind_rndis_config(struct usb_configuration *c)
+{
+	int status = 0;
+
+	f_rndis = usb_get_function(fi_rndis);
+	if (IS_ERR(f_rndis))
+		return PTR_ERR(f_rndis);
+
+	status = usb_add_function(c, f_rndis);
+	if (status < 0)
+		usb_put_function(f_rndis);
+
+	return status;
+}
+
+#endif