// 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");