diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/usb/gadget/function/f_phonet.c | 732 |
1 files changed, 732 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_phonet.c b/drivers/usb/gadget/function/f_phonet.c new file mode 100644 index 000000000..0bebbdf3f --- /dev/null +++ b/drivers/usb/gadget/function/f_phonet.c @@ -0,0 +1,732 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * f_phonet.c -- USB CDC Phonet function + * + * Copyright (C) 2007-2008 Nokia Corporation. All rights reserved. + * + * Author: Rémi Denis-Courmont + */ + +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/device.h> + +#include <linux/netdevice.h> +#include <linux/if_ether.h> +#include <linux/if_phonet.h> +#include <linux/if_arp.h> + +#include <linux/usb/ch9.h> +#include <linux/usb/cdc.h> +#include <linux/usb/composite.h> + +#include "u_phonet.h" +#include "u_ether.h" + +#define PN_MEDIA_USB 0x1B +#define MAXPACKET 512 +#if (PAGE_SIZE % MAXPACKET) +#error MAXPACKET must divide PAGE_SIZE! +#endif + +/*-------------------------------------------------------------------------*/ + +struct phonet_port { + struct f_phonet *usb; + spinlock_t lock; +}; + +struct f_phonet { + struct usb_function function; + struct { + struct sk_buff *skb; + spinlock_t lock; + } rx; + struct net_device *dev; + struct usb_ep *in_ep, *out_ep; + + struct usb_request *in_req; + struct usb_request *out_reqv[]; +}; + +static int phonet_rxq_size = 17; + +static inline struct f_phonet *func_to_pn(struct usb_function *f) +{ + return container_of(f, struct f_phonet, function); +} + +/*-------------------------------------------------------------------------*/ + +#define USB_CDC_SUBCLASS_PHONET 0xfe +#define USB_CDC_PHONET_TYPE 0xab + +static struct usb_interface_descriptor +pn_control_intf_desc = { + .bLength = sizeof pn_control_intf_desc, + .bDescriptorType = USB_DT_INTERFACE, + + /* .bInterfaceNumber = DYNAMIC, */ + .bInterfaceClass = USB_CLASS_COMM, + .bInterfaceSubClass = USB_CDC_SUBCLASS_PHONET, +}; + +static const struct usb_cdc_header_desc +pn_header_desc = { + .bLength = sizeof pn_header_desc, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubType = USB_CDC_HEADER_TYPE, + .bcdCDC = cpu_to_le16(0x0110), +}; + +static const struct usb_cdc_header_desc +pn_phonet_desc = { + .bLength = sizeof pn_phonet_desc, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubType = USB_CDC_PHONET_TYPE, + .bcdCDC = cpu_to_le16(0x1505), /* ??? */ +}; + +static struct usb_cdc_union_desc +pn_union_desc = { + .bLength = sizeof pn_union_desc, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubType = USB_CDC_UNION_TYPE, + + /* .bMasterInterface0 = DYNAMIC, */ + /* .bSlaveInterface0 = DYNAMIC, */ +}; + +static struct usb_interface_descriptor +pn_data_nop_intf_desc = { + .bLength = sizeof pn_data_nop_intf_desc, + .bDescriptorType = USB_DT_INTERFACE, + + /* .bInterfaceNumber = DYNAMIC, */ + .bAlternateSetting = 0, + .bNumEndpoints = 0, + .bInterfaceClass = USB_CLASS_CDC_DATA, +}; + +static struct usb_interface_descriptor +pn_data_intf_desc = { + .bLength = sizeof pn_data_intf_desc, + .bDescriptorType = USB_DT_INTERFACE, + + /* .bInterfaceNumber = DYNAMIC, */ + .bAlternateSetting = 1, + .bNumEndpoints = 2, + .bInterfaceClass = USB_CLASS_CDC_DATA, +}; + +static struct usb_endpoint_descriptor +pn_fs_sink_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_endpoint_descriptor +pn_hs_sink_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(MAXPACKET), +}; + +static struct usb_endpoint_descriptor +pn_fs_source_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_endpoint_descriptor +pn_hs_source_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 *fs_pn_function[] = { + (struct usb_descriptor_header *) &pn_control_intf_desc, + (struct usb_descriptor_header *) &pn_header_desc, + (struct usb_descriptor_header *) &pn_phonet_desc, + (struct usb_descriptor_header *) &pn_union_desc, + (struct usb_descriptor_header *) &pn_data_nop_intf_desc, + (struct usb_descriptor_header *) &pn_data_intf_desc, + (struct usb_descriptor_header *) &pn_fs_sink_desc, + (struct usb_descriptor_header *) &pn_fs_source_desc, + NULL, +}; + +static struct usb_descriptor_header *hs_pn_function[] = { + (struct usb_descriptor_header *) &pn_control_intf_desc, + (struct usb_descriptor_header *) &pn_header_desc, + (struct usb_descriptor_header *) &pn_phonet_desc, + (struct usb_descriptor_header *) &pn_union_desc, + (struct usb_descriptor_header *) &pn_data_nop_intf_desc, + (struct usb_descriptor_header *) &pn_data_intf_desc, + (struct usb_descriptor_header *) &pn_hs_sink_desc, + (struct usb_descriptor_header *) &pn_hs_source_desc, + NULL, +}; + +/*-------------------------------------------------------------------------*/ + +static int pn_net_open(struct net_device *dev) +{ + netif_wake_queue(dev); + return 0; +} + +static int pn_net_close(struct net_device *dev) +{ + netif_stop_queue(dev); + return 0; +} + +static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct f_phonet *fp = ep->driver_data; + struct net_device *dev = fp->dev; + struct sk_buff *skb = req->context; + + switch (req->status) { + case 0: + dev->stats.tx_packets++; + dev->stats.tx_bytes += skb->len; + break; + + case -ESHUTDOWN: /* disconnected */ + case -ECONNRESET: /* disabled */ + dev->stats.tx_aborted_errors++; + fallthrough; + default: + dev->stats.tx_errors++; + } + + dev_kfree_skb_any(skb); + netif_wake_queue(dev); +} + +static netdev_tx_t pn_net_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct phonet_port *port = netdev_priv(dev); + struct f_phonet *fp; + struct usb_request *req; + unsigned long flags; + + if (skb->protocol != htons(ETH_P_PHONET)) + goto out; + + spin_lock_irqsave(&port->lock, flags); + fp = port->usb; + if (unlikely(!fp)) /* race with carrier loss */ + goto out_unlock; + + req = fp->in_req; + req->buf = skb->data; + req->length = skb->len; + req->complete = pn_tx_complete; + req->zero = 1; + req->context = skb; + + if (unlikely(usb_ep_queue(fp->in_ep, req, GFP_ATOMIC))) + goto out_unlock; + + netif_stop_queue(dev); + skb = NULL; + +out_unlock: + spin_unlock_irqrestore(&port->lock, flags); +out: + if (unlikely(skb)) { + dev_kfree_skb(skb); + dev->stats.tx_dropped++; + } + return NETDEV_TX_OK; +} + +static const struct net_device_ops pn_netdev_ops = { + .ndo_open = pn_net_open, + .ndo_stop = pn_net_close, + .ndo_start_xmit = pn_net_xmit, +}; + +static void pn_net_setup(struct net_device *dev) +{ + const u8 addr = PN_MEDIA_USB; + + dev->features = 0; + dev->type = ARPHRD_PHONET; + dev->flags = IFF_POINTOPOINT | IFF_NOARP; + dev->mtu = PHONET_DEV_MTU; + dev->min_mtu = PHONET_MIN_MTU; + dev->max_mtu = PHONET_MAX_MTU; + dev->hard_header_len = 1; + dev->addr_len = 1; + dev_addr_set(dev, &addr); + + dev->tx_queue_len = 1; + + dev->netdev_ops = &pn_netdev_ops; + dev->needs_free_netdev = true; + dev->header_ops = &phonet_header_ops; +} + +/*-------------------------------------------------------------------------*/ + +/* + * Queue buffer for data from the host + */ +static int +pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags) +{ + struct page *page; + int err; + + page = __dev_alloc_page(gfp_flags | __GFP_NOMEMALLOC); + if (!page) + return -ENOMEM; + + req->buf = page_address(page); + req->length = PAGE_SIZE; + req->context = page; + + err = usb_ep_queue(fp->out_ep, req, gfp_flags); + if (unlikely(err)) + put_page(page); + return err; +} + +static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct f_phonet *fp = ep->driver_data; + struct net_device *dev = fp->dev; + struct page *page = req->context; + struct sk_buff *skb; + unsigned long flags; + int status = req->status; + + switch (status) { + case 0: + spin_lock_irqsave(&fp->rx.lock, flags); + skb = fp->rx.skb; + if (!skb) + skb = fp->rx.skb = netdev_alloc_skb(dev, 12); + if (req->actual < req->length) /* Last fragment */ + fp->rx.skb = NULL; + spin_unlock_irqrestore(&fp->rx.lock, flags); + + if (unlikely(!skb)) + break; + + if (skb->len == 0) { /* First fragment */ + skb->protocol = htons(ETH_P_PHONET); + skb_reset_mac_header(skb); + /* Can't use pskb_pull() on page in IRQ */ + skb_put_data(skb, page_address(page), 1); + } + + skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, + skb->len <= 1, req->actual, PAGE_SIZE); + page = NULL; + + if (req->actual < req->length) { /* Last fragment */ + skb->dev = dev; + dev->stats.rx_packets++; + dev->stats.rx_bytes += skb->len; + + netif_rx(skb); + } + break; + + /* Do not resubmit in these cases: */ + case -ESHUTDOWN: /* disconnect */ + case -ECONNABORTED: /* hw reset */ + case -ECONNRESET: /* dequeued (unlink or netif down) */ + req = NULL; + break; + + /* Do resubmit in these cases: */ + case -EOVERFLOW: /* request buffer overflow */ + dev->stats.rx_over_errors++; + fallthrough; + default: + dev->stats.rx_errors++; + break; + } + + if (page) + put_page(page); + if (req) + pn_rx_submit(fp, req, GFP_ATOMIC); +} + +/*-------------------------------------------------------------------------*/ + +static void __pn_reset(struct usb_function *f) +{ + struct f_phonet *fp = func_to_pn(f); + struct net_device *dev = fp->dev; + struct phonet_port *port = netdev_priv(dev); + + netif_carrier_off(dev); + port->usb = NULL; + + usb_ep_disable(fp->out_ep); + usb_ep_disable(fp->in_ep); + if (fp->rx.skb) { + dev_kfree_skb_irq(fp->rx.skb); + fp->rx.skb = NULL; + } +} + +static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt) +{ + struct f_phonet *fp = func_to_pn(f); + struct usb_gadget *gadget = fp->function.config->cdev->gadget; + + if (intf == pn_control_intf_desc.bInterfaceNumber) + /* control interface, no altsetting */ + return (alt > 0) ? -EINVAL : 0; + + if (intf == pn_data_intf_desc.bInterfaceNumber) { + struct net_device *dev = fp->dev; + struct phonet_port *port = netdev_priv(dev); + + /* data intf (0: inactive, 1: active) */ + if (alt > 1) + return -EINVAL; + + spin_lock(&port->lock); + + if (fp->in_ep->enabled) + __pn_reset(f); + + if (alt == 1) { + int i; + + if (config_ep_by_speed(gadget, f, fp->in_ep) || + config_ep_by_speed(gadget, f, fp->out_ep)) { + fp->in_ep->desc = NULL; + fp->out_ep->desc = NULL; + spin_unlock(&port->lock); + return -EINVAL; + } + usb_ep_enable(fp->out_ep); + usb_ep_enable(fp->in_ep); + + port->usb = fp; + fp->out_ep->driver_data = fp; + fp->in_ep->driver_data = fp; + + netif_carrier_on(dev); + for (i = 0; i < phonet_rxq_size; i++) + pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC); + } + spin_unlock(&port->lock); + return 0; + } + + return -EINVAL; +} + +static int pn_get_alt(struct usb_function *f, unsigned intf) +{ + struct f_phonet *fp = func_to_pn(f); + + if (intf == pn_control_intf_desc.bInterfaceNumber) + return 0; + + if (intf == pn_data_intf_desc.bInterfaceNumber) { + struct phonet_port *port = netdev_priv(fp->dev); + u8 alt; + + spin_lock(&port->lock); + alt = port->usb != NULL; + spin_unlock(&port->lock); + return alt; + } + + return -EINVAL; +} + +static void pn_disconnect(struct usb_function *f) +{ + struct f_phonet *fp = func_to_pn(f); + struct phonet_port *port = netdev_priv(fp->dev); + unsigned long flags; + + /* remain disabled until set_alt */ + spin_lock_irqsave(&port->lock, flags); + __pn_reset(f); + spin_unlock_irqrestore(&port->lock, flags); +} + +/*-------------------------------------------------------------------------*/ + +static int pn_bind(struct usb_configuration *c, struct usb_function *f) +{ + struct usb_composite_dev *cdev = c->cdev; + struct usb_gadget *gadget = cdev->gadget; + struct f_phonet *fp = func_to_pn(f); + struct usb_ep *ep; + int status, i; + + struct f_phonet_opts *phonet_opts; + + phonet_opts = container_of(f->fi, struct f_phonet_opts, func_inst); + + /* + * in drivers/usb/gadget/configfs.c:configfs_composite_bind() + * configurations are bound in sequence with list_for_each_entry, + * in each configuration its functions are bound in sequence + * with list_for_each_entry, so we assume no race condition + * with regard to phonet_opts->bound access + */ + if (!phonet_opts->bound) { + gphonet_set_gadget(phonet_opts->net, gadget); + status = gphonet_register_netdev(phonet_opts->net); + if (status) + return status; + phonet_opts->bound = true; + } + + /* Reserve interface IDs */ + status = usb_interface_id(c, f); + if (status < 0) + goto err; + pn_control_intf_desc.bInterfaceNumber = status; + pn_union_desc.bMasterInterface0 = status; + + status = usb_interface_id(c, f); + if (status < 0) + goto err; + pn_data_nop_intf_desc.bInterfaceNumber = status; + pn_data_intf_desc.bInterfaceNumber = status; + pn_union_desc.bSlaveInterface0 = status; + + /* Reserve endpoints */ + status = -ENODEV; + ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc); + if (!ep) + goto err; + fp->out_ep = ep; + + ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc); + if (!ep) + goto err; + fp->in_ep = ep; + + pn_hs_sink_desc.bEndpointAddress = pn_fs_sink_desc.bEndpointAddress; + pn_hs_source_desc.bEndpointAddress = pn_fs_source_desc.bEndpointAddress; + + /* Do not try to bind Phonet twice... */ + status = usb_assign_descriptors(f, fs_pn_function, hs_pn_function, + NULL, NULL); + if (status) + goto err; + + /* Incoming USB requests */ + status = -ENOMEM; + for (i = 0; i < phonet_rxq_size; i++) { + struct usb_request *req; + + req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL); + if (!req) + goto err_req; + + req->complete = pn_rx_complete; + fp->out_reqv[i] = req; + } + + /* Outgoing USB requests */ + fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL); + if (!fp->in_req) + goto err_req; + + INFO(cdev, "USB CDC Phonet function\n"); + INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name, + fp->out_ep->name, fp->in_ep->name); + return 0; + +err_req: + for (i = 0; i < phonet_rxq_size && fp->out_reqv[i]; i++) + usb_ep_free_request(fp->out_ep, fp->out_reqv[i]); + usb_free_all_descriptors(f); +err: + ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n"); + return status; +} + +static inline struct f_phonet_opts *to_f_phonet_opts(struct config_item *item) +{ + return container_of(to_config_group(item), struct f_phonet_opts, + func_inst.group); +} + +static void phonet_attr_release(struct config_item *item) +{ + struct f_phonet_opts *opts = to_f_phonet_opts(item); + + usb_put_function_instance(&opts->func_inst); +} + +static struct configfs_item_operations phonet_item_ops = { + .release = phonet_attr_release, +}; + +static ssize_t f_phonet_ifname_show(struct config_item *item, char *page) +{ + return gether_get_ifname(to_f_phonet_opts(item)->net, page, PAGE_SIZE); +} + +CONFIGFS_ATTR_RO(f_phonet_, ifname); + +static struct configfs_attribute *phonet_attrs[] = { + &f_phonet_attr_ifname, + NULL, +}; + +static const struct config_item_type phonet_func_type = { + .ct_item_ops = &phonet_item_ops, + .ct_attrs = phonet_attrs, + .ct_owner = THIS_MODULE, +}; + +static void phonet_free_inst(struct usb_function_instance *f) +{ + struct f_phonet_opts *opts; + + opts = container_of(f, struct f_phonet_opts, func_inst); + if (opts->bound) + gphonet_cleanup(opts->net); + else + free_netdev(opts->net); + kfree(opts); +} + +static struct usb_function_instance *phonet_alloc_inst(void) +{ + struct f_phonet_opts *opts; + + opts = kzalloc(sizeof(*opts), GFP_KERNEL); + if (!opts) + return ERR_PTR(-ENOMEM); + + opts->func_inst.free_func_inst = phonet_free_inst; + opts->net = gphonet_setup_default(); + if (IS_ERR(opts->net)) { + struct net_device *net = opts->net; + kfree(opts); + return ERR_CAST(net); + } + + config_group_init_type_name(&opts->func_inst.group, "", + &phonet_func_type); + + return &opts->func_inst; +} + +static void phonet_free(struct usb_function *f) +{ + struct f_phonet *phonet; + + phonet = func_to_pn(f); + kfree(phonet); +} + +static void pn_unbind(struct usb_configuration *c, struct usb_function *f) +{ + struct f_phonet *fp = func_to_pn(f); + int i; + + /* We are already disconnected */ + if (fp->in_req) + usb_ep_free_request(fp->in_ep, fp->in_req); + for (i = 0; i < phonet_rxq_size; i++) + if (fp->out_reqv[i]) + usb_ep_free_request(fp->out_ep, fp->out_reqv[i]); + + usb_free_all_descriptors(f); +} + +static struct usb_function *phonet_alloc(struct usb_function_instance *fi) +{ + struct f_phonet *fp; + struct f_phonet_opts *opts; + + fp = kzalloc(struct_size(fp, out_reqv, phonet_rxq_size), GFP_KERNEL); + if (!fp) + return ERR_PTR(-ENOMEM); + + opts = container_of(fi, struct f_phonet_opts, func_inst); + + fp->dev = opts->net; + fp->function.name = "phonet"; + fp->function.bind = pn_bind; + fp->function.unbind = pn_unbind; + fp->function.set_alt = pn_set_alt; + fp->function.get_alt = pn_get_alt; + fp->function.disable = pn_disconnect; + fp->function.free_func = phonet_free; + spin_lock_init(&fp->rx.lock); + + return &fp->function; +} + +struct net_device *gphonet_setup_default(void) +{ + struct net_device *dev; + struct phonet_port *port; + + /* Create net device */ + dev = alloc_netdev(sizeof(*port), "upnlink%d", NET_NAME_UNKNOWN, + pn_net_setup); + if (!dev) + return ERR_PTR(-ENOMEM); + + port = netdev_priv(dev); + spin_lock_init(&port->lock); + netif_carrier_off(dev); + + return dev; +} + +void gphonet_set_gadget(struct net_device *net, struct usb_gadget *g) +{ + SET_NETDEV_DEV(net, &g->dev); +} + +int gphonet_register_netdev(struct net_device *net) +{ + int status; + + status = register_netdev(net); + if (status) + free_netdev(net); + + return status; +} + +void gphonet_cleanup(struct net_device *dev) +{ + unregister_netdev(dev); +} + +DECLARE_USB_FUNCTION_INIT(phonet, phonet_alloc_inst, phonet_alloc); +MODULE_AUTHOR("Rémi Denis-Courmont"); +MODULE_LICENSE("GPL"); |