1 files changed, 491 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_obex.c b/drivers/usb/gadget/function/f_obex.c
new file mode 100644
index 000000000..ab26d84ed
--- /dev/null
+++ b/drivers/usb/gadget/function/f_obex.c
@@ -0,0 +1,491 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * f_obex.c -- USB CDC OBEX function driver
+ *
+ * Copyright (C) 2008 Nokia Corporation
+ * Contact: Felipe Balbi <felipe.balbi@nokia.com>
+ *
+ * Based on f_acm.c by Al Borchers and David Brownell.
+ */
+
+/* #define VERBOSE_DEBUG */
+
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/module.h>
+
+#include "u_serial.h"
+
+
+/*
+ * This CDC OBEX function support just packages a TTY-ish byte stream.
+ * A user mode server will put it into "raw" mode and handle all the
+ * relevant protocol details ... this is just a kernel passthrough.
+ * When possible, we prevent gadget enumeration until that server is
+ * ready to handle the commands.
+ */
+
+struct f_obex {
+	struct gserial			port;
+	u8				ctrl_id;
+	u8				data_id;
+	u8				cur_alt;
+	u8				port_num;
+};
+
+static inline struct f_obex *func_to_obex(struct usb_function *f)
+{
+	return container_of(f, struct f_obex, port.func);
+}
+
+static inline struct f_obex *port_to_obex(struct gserial *p)
+{
+	return container_of(p, struct f_obex, port);
+}
+
+/*-------------------------------------------------------------------------*/
+
+#define OBEX_CTRL_IDX	0
+#define OBEX_DATA_IDX	1
+
+static struct usb_string obex_string_defs[] = {
+	[OBEX_CTRL_IDX].s	= "CDC Object Exchange (OBEX)",
+	[OBEX_DATA_IDX].s	= "CDC OBEX Data",
+	{  },	/* end of list */
+};
+
+static struct usb_gadget_strings obex_string_table = {
+	.language		= 0x0409,	/* en-US */
+	.strings		= obex_string_defs,
+};
+
+static struct usb_gadget_strings *obex_strings[] = {
+	&obex_string_table,
+	NULL,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_interface_descriptor obex_control_intf = {
+	.bLength		= sizeof(obex_control_intf),
+	.bDescriptorType	= USB_DT_INTERFACE,
+	.bInterfaceNumber	= 0,
+
+	.bAlternateSetting	= 0,
+	.bNumEndpoints		= 0,
+	.bInterfaceClass	= USB_CLASS_COMM,
+	.bInterfaceSubClass	= USB_CDC_SUBCLASS_OBEX,
+};
+
+static struct usb_interface_descriptor obex_data_nop_intf = {
+	.bLength		= sizeof(obex_data_nop_intf),
+	.bDescriptorType	= USB_DT_INTERFACE,
+	.bInterfaceNumber	= 1,
+
+	.bAlternateSetting	= 0,
+	.bNumEndpoints		= 0,
+	.bInterfaceClass	= USB_CLASS_CDC_DATA,
+};
+
+static struct usb_interface_descriptor obex_data_intf = {
+	.bLength		= sizeof(obex_data_intf),
+	.bDescriptorType	= USB_DT_INTERFACE,
+	.bInterfaceNumber	= 2,
+
+	.bAlternateSetting	= 1,
+	.bNumEndpoints		= 2,
+	.bInterfaceClass	= USB_CLASS_CDC_DATA,
+};
+
+static struct usb_cdc_header_desc obex_cdc_header_desc = {
+	.bLength		= sizeof(obex_cdc_header_desc),
+	.bDescriptorType	= USB_DT_CS_INTERFACE,
+	.bDescriptorSubType	= USB_CDC_HEADER_TYPE,
+	.bcdCDC			= cpu_to_le16(0x0120),
+};
+
+static struct usb_cdc_union_desc obex_cdc_union_desc = {
+	.bLength		= sizeof(obex_cdc_union_desc),
+	.bDescriptorType	= USB_DT_CS_INTERFACE,
+	.bDescriptorSubType	= USB_CDC_UNION_TYPE,
+	.bMasterInterface0	= 1,
+	.bSlaveInterface0	= 2,
+};
+
+static struct usb_cdc_obex_desc obex_desc = {
+	.bLength		= sizeof(obex_desc),
+	.bDescriptorType	= USB_DT_CS_INTERFACE,
+	.bDescriptorSubType	= USB_CDC_OBEX_TYPE,
+	.bcdVersion		= cpu_to_le16(0x0100),
+};
+
+/* High-Speed Support */
+
+static struct usb_endpoint_descriptor obex_hs_ep_out_desc = {
+	.bLength		= USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType	= USB_DT_ENDPOINT,
+
+	.bEndpointAddress	= USB_DIR_OUT,
+	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize		= cpu_to_le16(512),
+};
+
+static struct usb_endpoint_descriptor obex_hs_ep_in_desc = {
+	.bLength		= USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType	= USB_DT_ENDPOINT,
+
+	.bEndpointAddress	= USB_DIR_IN,
+	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize		= cpu_to_le16(512),
+};
+
+static struct usb_descriptor_header *hs_function[] = {
+	(struct usb_descriptor_header *) &obex_control_intf,
+	(struct usb_descriptor_header *) &obex_cdc_header_desc,
+	(struct usb_descriptor_header *) &obex_desc,
+	(struct usb_descriptor_header *) &obex_cdc_union_desc,
+
+	(struct usb_descriptor_header *) &obex_data_nop_intf,
+	(struct usb_descriptor_header *) &obex_data_intf,
+	(struct usb_descriptor_header *) &obex_hs_ep_in_desc,
+	(struct usb_descriptor_header *) &obex_hs_ep_out_desc,
+	NULL,
+};
+
+/* Full-Speed Support */
+
+static struct usb_endpoint_descriptor obex_fs_ep_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 obex_fs_ep_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 *fs_function[] = {
+	(struct usb_descriptor_header *) &obex_control_intf,
+	(struct usb_descriptor_header *) &obex_cdc_header_desc,
+	(struct usb_descriptor_header *) &obex_desc,
+	(struct usb_descriptor_header *) &obex_cdc_union_desc,
+
+	(struct usb_descriptor_header *) &obex_data_nop_intf,
+	(struct usb_descriptor_header *) &obex_data_intf,
+	(struct usb_descriptor_header *) &obex_fs_ep_in_desc,
+	(struct usb_descriptor_header *) &obex_fs_ep_out_desc,
+	NULL,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int obex_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
+{
+	struct f_obex		*obex = func_to_obex(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+
+	if (intf == obex->ctrl_id) {
+		if (alt != 0)
+			goto fail;
+		/* NOP */
+		dev_dbg(&cdev->gadget->dev,
+			"reset obex ttyGS%d control\n", obex->port_num);
+
+	} else if (intf == obex->data_id) {
+		if (alt > 1)
+			goto fail;
+
+		if (obex->port.in->enabled) {
+			dev_dbg(&cdev->gadget->dev,
+				"reset obex ttyGS%d\n", obex->port_num);
+			gserial_disconnect(&obex->port);
+		}
+
+		if (!obex->port.in->desc || !obex->port.out->desc) {
+			dev_dbg(&cdev->gadget->dev,
+				"init obex ttyGS%d\n", obex->port_num);
+			if (config_ep_by_speed(cdev->gadget, f,
+					       obex->port.in) ||
+			    config_ep_by_speed(cdev->gadget, f,
+					       obex->port.out)) {
+				obex->port.out->desc = NULL;
+				obex->port.in->desc = NULL;
+				goto fail;
+			}
+		}
+
+		if (alt == 1) {
+			dev_dbg(&cdev->gadget->dev,
+				"activate obex ttyGS%d\n", obex->port_num);
+			gserial_connect(&obex->port, obex->port_num);
+		}
+
+	} else
+		goto fail;
+
+	obex->cur_alt = alt;
+
+	return 0;
+
+fail:
+	return -EINVAL;
+}
+
+static int obex_get_alt(struct usb_function *f, unsigned intf)
+{
+	struct f_obex		*obex = func_to_obex(f);
+
+	return obex->cur_alt;
+}
+
+static void obex_disable(struct usb_function *f)
+{
+	struct f_obex	*obex = func_to_obex(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+
+	dev_dbg(&cdev->gadget->dev, "obex ttyGS%d disable\n", obex->port_num);
+	gserial_disconnect(&obex->port);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void obex_connect(struct gserial *g)
+{
+	struct f_obex		*obex = port_to_obex(g);
+	struct usb_composite_dev *cdev = g->func.config->cdev;
+	int			status;
+
+	status = usb_function_activate(&g->func);
+	if (status)
+		dev_dbg(&cdev->gadget->dev,
+			"obex ttyGS%d function activate --> %d\n",
+			obex->port_num, status);
+}
+
+static void obex_disconnect(struct gserial *g)
+{
+	struct f_obex		*obex = port_to_obex(g);
+	struct usb_composite_dev *cdev = g->func.config->cdev;
+	int			status;
+
+	status = usb_function_deactivate(&g->func);
+	if (status)
+		dev_dbg(&cdev->gadget->dev,
+			"obex ttyGS%d function deactivate --> %d\n",
+			obex->port_num, status);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* Some controllers can't support CDC OBEX ... */
+static inline bool can_support_obex(struct usb_configuration *c)
+{
+	/* Since the first interface is a NOP, we can ignore the
+	 * issue of multi-interface support on most controllers.
+	 *
+	 * Altsettings are mandatory, however...
+	 */
+	if (!gadget_is_altset_supported(c->cdev->gadget))
+		return false;
+
+	/* everything else is *probably* fine ... */
+	return true;
+}
+
+static int obex_bind(struct usb_configuration *c, struct usb_function *f)
+{
+	struct usb_composite_dev *cdev = c->cdev;
+	struct f_obex		*obex = func_to_obex(f);
+	struct usb_string	*us;
+	int			status;
+	struct usb_ep		*ep;
+
+	if (!can_support_obex(c))
+		return -EINVAL;
+
+	us = usb_gstrings_attach(cdev, obex_strings,
+				 ARRAY_SIZE(obex_string_defs));
+	if (IS_ERR(us))
+		return PTR_ERR(us);
+	obex_control_intf.iInterface = us[OBEX_CTRL_IDX].id;
+	obex_data_nop_intf.iInterface = us[OBEX_DATA_IDX].id;
+	obex_data_intf.iInterface = us[OBEX_DATA_IDX].id;
+
+	/* allocate instance-specific interface IDs, and patch descriptors */
+
+	status = usb_interface_id(c, f);
+	if (status < 0)
+		goto fail;
+	obex->ctrl_id = status;
+
+	obex_control_intf.bInterfaceNumber = status;
+	obex_cdc_union_desc.bMasterInterface0 = status;
+
+	status = usb_interface_id(c, f);
+	if (status < 0)
+		goto fail;
+	obex->data_id = status;
+
+	obex_data_nop_intf.bInterfaceNumber = status;
+	obex_data_intf.bInterfaceNumber = status;
+	obex_cdc_union_desc.bSlaveInterface0 = status;
+
+	/* allocate instance-specific endpoints */
+
+	status = -ENODEV;
+	ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_in_desc);
+	if (!ep)
+		goto fail;
+	obex->port.in = ep;
+
+	ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_out_desc);
+	if (!ep)
+		goto fail;
+	obex->port.out = ep;
+
+	/* support all relevant hardware speeds... we expect that when
+	 * hardware is dual speed, all bulk-capable endpoints work at
+	 * both speeds
+	 */
+
+	obex_hs_ep_in_desc.bEndpointAddress =
+		obex_fs_ep_in_desc.bEndpointAddress;
+	obex_hs_ep_out_desc.bEndpointAddress =
+		obex_fs_ep_out_desc.bEndpointAddress;
+
+	status = usb_assign_descriptors(f, fs_function, hs_function, NULL,
+					NULL);
+	if (status)
+		goto fail;
+
+	dev_dbg(&cdev->gadget->dev, "obex ttyGS%d: %s speed IN/%s OUT/%s\n",
+		obex->port_num,
+		gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
+		obex->port.in->name, obex->port.out->name);
+
+	return 0;
+
+fail:
+	ERROR(cdev, "%s/%p: can't bind, err %d\n", f->name, f, status);
+
+	return status;
+}
+
+static inline struct f_serial_opts *to_f_serial_opts(struct config_item *item)
+{
+	return container_of(to_config_group(item), struct f_serial_opts,
+			    func_inst.group);
+}
+
+static void obex_attr_release(struct config_item *item)
+{
+	struct f_serial_opts *opts = to_f_serial_opts(item);
+
+	usb_put_function_instance(&opts->func_inst);
+}
+
+static struct configfs_item_operations obex_item_ops = {
+	.release	= obex_attr_release,
+};
+
+static ssize_t f_obex_port_num_show(struct config_item *item, char *page)
+{
+	return sprintf(page, "%u\n", to_f_serial_opts(item)->port_num);
+}
+
+CONFIGFS_ATTR_RO(f_obex_, port_num);
+
+static struct configfs_attribute *acm_attrs[] = {
+	&f_obex_attr_port_num,
+	NULL,
+};
+
+static const struct config_item_type obex_func_type = {
+	.ct_item_ops	= &obex_item_ops,
+	.ct_attrs	= acm_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static void obex_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 *obex_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 = obex_free_inst;
+	ret = gserial_alloc_line_no_console(&opts->port_num);
+	if (ret) {
+		kfree(opts);
+		return ERR_PTR(ret);
+	}
+	config_group_init_type_name(&opts->func_inst.group, "",
+				    &obex_func_type);
+
+	return &opts->func_inst;
+}
+
+static void obex_free(struct usb_function *f)
+{
+	struct f_obex *obex;
+
+	obex = func_to_obex(f);
+	kfree(obex);
+}
+
+static void obex_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+	usb_free_all_descriptors(f);
+}
+
+static struct usb_function *obex_alloc(struct usb_function_instance *fi)
+{
+	struct f_obex	*obex;
+	struct f_serial_opts *opts;
+
+	/* allocate and initialize one new instance */
+	obex = kzalloc(sizeof(*obex), GFP_KERNEL);
+	if (!obex)
+		return ERR_PTR(-ENOMEM);
+
+	opts = container_of(fi, struct f_serial_opts, func_inst);
+
+	obex->port_num = opts->port_num;
+
+	obex->port.connect = obex_connect;
+	obex->port.disconnect = obex_disconnect;
+
+	obex->port.func.name = "obex";
+	/* descriptors are per-instance copies */
+	obex->port.func.bind = obex_bind;
+	obex->port.func.unbind = obex_unbind;
+	obex->port.func.set_alt = obex_set_alt;
+	obex->port.func.get_alt = obex_get_alt;
+	obex->port.func.disable = obex_disable;
+	obex->port.func.free_func = obex_free;
+	obex->port.func.bind_deactivated = true;
+
+	return &obex->port.func;
+}
+
+DECLARE_USB_FUNCTION_INIT(obex, obex_alloc_inst, obex_alloc);
+MODULE_AUTHOR("Felipe Balbi");
+MODULE_LICENSE("GPL");