usb: gadget: Standard ECM function driver for QCOM chipsets
New function driver to support Standard ECM with adaptions to
QCOM chipsets (Data path is over SPS BAM-to-BAM).
Standard ECM function was added to android gadget.
CRs-Fixed: 358338
Change-Id: Ic1ed2f7ee7ac50601ba5dc43d06c28bffe2c5c23
Signed-off-by: Ofir Cohen <ofirc@codeaurora.org>
diff --git a/drivers/usb/gadget/f_qc_ecm.c b/drivers/usb/gadget/f_qc_ecm.c
new file mode 100644
index 0000000..98a29ae
--- /dev/null
+++ b/drivers/usb/gadget/f_qc_ecm.c
@@ -0,0 +1,869 @@
+/*
+ * f_qc_ecm.c -- USB CDC Ethernet (ECM) link function driver
+ *
+ * Copyright (C) 2003-2005,2008 David Brownell
+ * Copyright (C) 2008 Nokia Corporation
+ * Copyright (c) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/* #define VERBOSE_DEBUG */
+
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/etherdevice.h>
+
+#include "u_ether.h"
+#include "u_qc_ether.h"
+
+
+/*
+ * This function is a "CDC Ethernet Networking Control Model" (CDC ECM)
+ * Ethernet link. The data transfer model is simple (packets sent and
+ * received over bulk endpoints using normal short packet termination),
+ * and the control model exposes various data and optional notifications.
+ *
+ * ECM is well standardized and (except for Microsoft) supported by most
+ * operating systems with USB host support. It's the preferred interop
+ * solution for Ethernet over USB, at least for firmware based solutions.
+ * (Hardware solutions tend to be more minimalist.) A newer and simpler
+ * "Ethernet Emulation Model" (CDC EEM) hasn't yet caught on.
+ *
+ * Note that ECM requires the use of "alternate settings" for its data
+ * interface. This means that the set_alt() method has real work to do,
+ * and also means that a get_alt() method is required.
+ *
+ * This function is based on USB CDC Ethernet link function driver and
+ * contains MSM specific implementation.
+ */
+
+
+enum ecm_qc_notify_state {
+ ECM_QC_NOTIFY_NONE, /* don't notify */
+ ECM_QC_NOTIFY_CONNECT, /* issue CONNECT next */
+ ECM_QC_NOTIFY_SPEED, /* issue SPEED_CHANGE next */
+};
+
+struct f_ecm_qc {
+ struct qc_gether port;
+ u8 ctrl_id, data_id;
+
+ char ethaddr[14];
+
+ struct usb_ep *notify;
+ struct usb_request *notify_req;
+ u8 notify_state;
+ bool is_open;
+};
+
+static inline struct f_ecm_qc *func_to_ecm_qc(struct usb_function *f)
+{
+ return container_of(f, struct f_ecm_qc, port.func);
+}
+
+/* peak (theoretical) bulk transfer rate in bits-per-second */
+static inline unsigned ecm_qc_bitrate(struct usb_gadget *g)
+{
+ if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
+ return 13 * 512 * 8 * 1000 * 8;
+ else
+ return 19 * 64 * 1 * 1000 * 8;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Include the status endpoint if we can, even though it's optional.
+ *
+ * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
+ * packet, to simplify cancellation; and a big transfer interval, to
+ * waste less bandwidth.
+ *
+ * Some drivers (like Linux 2.4 cdc-ether!) "need" it to exist even
+ * if they ignore the connect/disconnect notifications that real aether
+ * can provide. More advanced cdc configurations might want to support
+ * encapsulated commands (vendor-specific, using control-OUT).
+ */
+
+#define ECM_QC_LOG2_STATUS_INTERVAL_MSEC 5 /* 1 << 5 == 32 msec */
+#define ECM_QC_STATUS_BYTECOUNT 16 /* 8 byte header + data */
+
+/* currently only one std ecm instance is supported */
+#define ECM_QC_NO_PORTS 1
+
+/* interface descriptor: */
+
+static struct usb_interface_descriptor ecm_qc_control_intf = {
+ .bLength = sizeof ecm_qc_control_intf,
+ .bDescriptorType = USB_DT_INTERFACE,
+
+ /* .bInterfaceNumber = DYNAMIC */
+ /* status endpoint is optional; this could be patched later */
+ .bNumEndpoints = 1,
+ .bInterfaceClass = USB_CLASS_COMM,
+ .bInterfaceSubClass = USB_CDC_SUBCLASS_ETHERNET,
+ .bInterfaceProtocol = USB_CDC_PROTO_NONE,
+ /* .iInterface = DYNAMIC */
+};
+
+static struct usb_cdc_header_desc ecm_qc_header_desc = {
+ .bLength = sizeof ecm_qc_header_desc,
+ .bDescriptorType = USB_DT_CS_INTERFACE,
+ .bDescriptorSubType = USB_CDC_HEADER_TYPE,
+
+ .bcdCDC = cpu_to_le16(0x0110),
+};
+
+static struct usb_cdc_union_desc ecm_qc_union_desc = {
+ .bLength = sizeof(ecm_qc_union_desc),
+ .bDescriptorType = USB_DT_CS_INTERFACE,
+ .bDescriptorSubType = USB_CDC_UNION_TYPE,
+ /* .bMasterInterface0 = DYNAMIC */
+ /* .bSlaveInterface0 = DYNAMIC */
+};
+
+static struct usb_cdc_ether_desc ecm_qc_desc = {
+ .bLength = sizeof ecm_qc_desc,
+ .bDescriptorType = USB_DT_CS_INTERFACE,
+ .bDescriptorSubType = USB_CDC_ETHERNET_TYPE,
+
+ /* this descriptor actually adds value, surprise! */
+ /* .iMACAddress = DYNAMIC */
+ .bmEthernetStatistics = cpu_to_le32(0), /* no statistics */
+ .wMaxSegmentSize = cpu_to_le16(ETH_FRAME_LEN),
+ .wNumberMCFilters = cpu_to_le16(0),
+ .bNumberPowerFilters = 0,
+};
+
+/* the default data interface has no endpoints ... */
+
+static struct usb_interface_descriptor ecm_qc_data_nop_intf = {
+ .bLength = sizeof ecm_qc_data_nop_intf,
+ .bDescriptorType = USB_DT_INTERFACE,
+
+ .bInterfaceNumber = 1,
+ .bAlternateSetting = 0,
+ .bNumEndpoints = 0,
+ .bInterfaceClass = USB_CLASS_CDC_DATA,
+ .bInterfaceSubClass = 0,
+ .bInterfaceProtocol = 0,
+ /* .iInterface = DYNAMIC */
+};
+
+/* ... but the "real" data interface has two bulk endpoints */
+
+static struct usb_interface_descriptor ecm_qc_data_intf = {
+ .bLength = sizeof ecm_qc_data_intf,
+ .bDescriptorType = USB_DT_INTERFACE,
+
+ .bInterfaceNumber = 1,
+ .bAlternateSetting = 1,
+ .bNumEndpoints = 2,
+ .bInterfaceClass = USB_CLASS_CDC_DATA,
+ .bInterfaceSubClass = 0,
+ .bInterfaceProtocol = 0,
+ /* .iInterface = DYNAMIC */
+};
+
+/* full speed support: */
+
+static struct usb_endpoint_descriptor ecm_qc_fs_notify_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ .wMaxPacketSize = cpu_to_le16(ECM_QC_STATUS_BYTECOUNT),
+ .bInterval = 1 << ECM_QC_LOG2_STATUS_INTERVAL_MSEC,
+};
+
+static struct usb_endpoint_descriptor ecm_qc_fs_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 ecm_qc_fs_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 *ecm_qc_fs_function[] = {
+ /* CDC ECM control descriptors */
+ (struct usb_descriptor_header *) &ecm_qc_control_intf,
+ (struct usb_descriptor_header *) &ecm_qc_header_desc,
+ (struct usb_descriptor_header *) &ecm_qc_union_desc,
+ (struct usb_descriptor_header *) &ecm_qc_desc,
+ /* NOTE: status endpoint might need to be removed */
+ (struct usb_descriptor_header *) &ecm_qc_fs_notify_desc,
+ /* data interface, altsettings 0 and 1 */
+ (struct usb_descriptor_header *) &ecm_qc_data_nop_intf,
+ (struct usb_descriptor_header *) &ecm_qc_data_intf,
+ (struct usb_descriptor_header *) &ecm_qc_fs_in_desc,
+ (struct usb_descriptor_header *) &ecm_qc_fs_out_desc,
+ NULL,
+};
+
+/* high speed support: */
+
+static struct usb_endpoint_descriptor ecm_qc_hs_notify_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_INT,
+ .wMaxPacketSize = cpu_to_le16(ECM_QC_STATUS_BYTECOUNT),
+ .bInterval = ECM_QC_LOG2_STATUS_INTERVAL_MSEC + 4,
+};
+static struct usb_endpoint_descriptor ecm_qc_hs_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_endpoint_descriptor ecm_qc_hs_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_descriptor_header *ecm_qc_hs_function[] = {
+ /* CDC ECM control descriptors */
+ (struct usb_descriptor_header *) &ecm_qc_control_intf,
+ (struct usb_descriptor_header *) &ecm_qc_header_desc,
+ (struct usb_descriptor_header *) &ecm_qc_union_desc,
+ (struct usb_descriptor_header *) &ecm_qc_desc,
+ /* NOTE: status endpoint might need to be removed */
+ (struct usb_descriptor_header *) &ecm_qc_hs_notify_desc,
+ /* data interface, altsettings 0 and 1 */
+ (struct usb_descriptor_header *) &ecm_qc_data_nop_intf,
+ (struct usb_descriptor_header *) &ecm_qc_data_intf,
+ (struct usb_descriptor_header *) &ecm_qc_hs_in_desc,
+ (struct usb_descriptor_header *) &ecm_qc_hs_out_desc,
+ NULL,
+};
+
+/* string descriptors: */
+
+static struct usb_string ecm_qc_string_defs[] = {
+ [0].s = "CDC Ethernet Control Model (ECM)",
+ [1].s = NULL /* DYNAMIC */,
+ [2].s = "CDC Ethernet Data",
+ { } /* end of list */
+};
+
+static struct usb_gadget_strings ecm_qc_string_table = {
+ .language = 0x0409, /* en-us */
+ .strings = ecm_qc_string_defs,
+};
+
+static struct usb_gadget_strings *ecm_qc_strings[] = {
+ &ecm_qc_string_table,
+ NULL,
+};
+
+static struct data_port ecm_qc_bam_port;
+
+static int ecm_qc_bam_setup(void)
+{
+ int ret;
+
+ ret = bam_data_setup(ECM_QC_NO_PORTS);
+ if (ret) {
+ pr_err("bam_data_setup failed err: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int ecm_qc_bam_connect(struct f_ecm_qc *dev)
+{
+ int ret;
+
+ ecm_qc_bam_port.func = dev->port.func;
+ ecm_qc_bam_port.in = dev->port.in_ep;
+ ecm_qc_bam_port.out = dev->port.out_ep;
+
+ /* currently we use the first connection */
+ ret = bam_data_connect(&ecm_qc_bam_port, 0, 0);
+ if (ret) {
+ pr_err("bam_data_connect failed: err:%d\n",
+ ret);
+ return ret;
+ } else {
+ pr_info("ecm bam connected\n");
+ }
+
+ return 0;
+}
+
+static int ecm_qc_bam_disconnect(struct f_ecm_qc *dev)
+{
+ pr_debug("dev:%p. %s Do nothing.\n",
+ dev, __func__);
+
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void ecm_qc_do_notify(struct f_ecm_qc *ecm)
+{
+ struct usb_request *req = ecm->notify_req;
+ struct usb_cdc_notification *event;
+ struct usb_composite_dev *cdev = ecm->port.func.config->cdev;
+ __le32 *data;
+ int status;
+
+ /* notification already in flight? */
+ if (!req)
+ return;
+
+ event = req->buf;
+ switch (ecm->notify_state) {
+ case ECM_QC_NOTIFY_NONE:
+ return;
+
+ case ECM_QC_NOTIFY_CONNECT:
+ event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
+ if (ecm->is_open)
+ event->wValue = cpu_to_le16(1);
+ else
+ event->wValue = cpu_to_le16(0);
+ event->wLength = 0;
+ req->length = sizeof *event;
+
+ DBG(cdev, "notify connect %s\n",
+ ecm->is_open ? "true" : "false");
+ ecm->notify_state = ECM_QC_NOTIFY_SPEED;
+ break;
+
+ case ECM_QC_NOTIFY_SPEED:
+ event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
+ event->wValue = cpu_to_le16(0);
+ event->wLength = cpu_to_le16(8);
+ req->length = ECM_QC_STATUS_BYTECOUNT;
+
+ /* SPEED_CHANGE data is up/down speeds in bits/sec */
+ data = req->buf + sizeof *event;
+ data[0] = cpu_to_le32(ecm_qc_bitrate(cdev->gadget));
+ data[1] = data[0];
+
+ DBG(cdev, "notify speed %d\n", ecm_qc_bitrate(cdev->gadget));
+ ecm->notify_state = ECM_QC_NOTIFY_NONE;
+ break;
+ }
+ event->bmRequestType = 0xA1;
+ event->wIndex = cpu_to_le16(ecm->ctrl_id);
+
+ ecm->notify_req = NULL;
+ status = usb_ep_queue(ecm->notify, req, GFP_ATOMIC);
+ if (status < 0) {
+ ecm->notify_req = req;
+ DBG(cdev, "notify --> %d\n", status);
+ }
+}
+
+static void ecm_qc_notify(struct f_ecm_qc *ecm)
+{
+ /* NOTE on most versions of Linux, host side cdc-ethernet
+ * won't listen for notifications until its netdevice opens.
+ * The first notification then sits in the FIFO for a long
+ * time, and the second one is queued.
+ */
+ ecm->notify_state = ECM_QC_NOTIFY_CONNECT;
+ ecm_qc_do_notify(ecm);
+}
+
+static void ecm_qc_notify_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct f_ecm_qc *ecm = req->context;
+
+ switch (req->status) {
+ case 0:
+ /* no fault */
+ break;
+ case -ECONNRESET:
+ case -ESHUTDOWN:
+ ecm->notify_state = ECM_QC_NOTIFY_NONE;
+ break;
+ default:
+ DBG(cdev, "event %02x --> %d\n",
+ event->bNotificationType, req->status);
+ break;
+ }
+ ecm->notify_req = req;
+ ecm_qc_do_notify(ecm);
+}
+
+static int ecm_qc_setup(struct usb_function *f,
+ const struct usb_ctrlrequest *ctrl)
+{
+ struct f_ecm_qc *ecm = func_to_ecm_qc(f);
+ struct usb_composite_dev *cdev = f->config->cdev;
+ struct usb_request *req = cdev->req;
+ int value = -EOPNOTSUPP;
+ u16 w_index = le16_to_cpu(ctrl->wIndex);
+ u16 w_value = le16_to_cpu(ctrl->wValue);
+ u16 w_length = le16_to_cpu(ctrl->wLength);
+
+ /* composite driver infrastructure handles everything except
+ * CDC class messages; interface activation uses set_alt().
+ */
+ switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
+ case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
+ | USB_CDC_SET_ETHERNET_PACKET_FILTER:
+ /* see 6.2.30: no data, wIndex = interface,
+ * wValue = packet filter bitmap
+ */
+ if (w_length != 0 || w_index != ecm->ctrl_id)
+ goto invalid;
+ DBG(cdev, "packet filter %02x\n", w_value);
+ /* REVISIT locking of cdc_filter. This assumes the UDC
+ * driver won't have a concurrent packet TX irq running on
+ * another CPU; or that if it does, this write is atomic...
+ */
+ ecm->port.cdc_filter = w_value;
+ value = 0;
+ break;
+
+ /* and optionally:
+ * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
+ * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
+ * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
+ * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
+ * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
+ * case USB_CDC_GET_ETHERNET_STATISTIC:
+ */
+
+ default:
+invalid:
+ DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
+ ctrl->bRequestType, ctrl->bRequest,
+ w_value, w_index, w_length);
+ }
+
+ /* respond with data transfer or status phase? */
+ if (value >= 0) {
+ DBG(cdev, "ecm req%02x.%02x v%04x i%04x l%d\n",
+ ctrl->bRequestType, ctrl->bRequest,
+ w_value, w_index, w_length);
+ req->zero = 0;
+ req->length = value;
+ value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
+ if (value < 0)
+ pr_err("ecm req %02x.%02x response err %d\n",
+ ctrl->bRequestType, ctrl->bRequest,
+ value);
+ }
+
+ /* device either stalls (value < 0) or reports success */
+ return value;
+}
+
+
+static int ecm_qc_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
+{
+ struct f_ecm_qc *ecm = func_to_ecm_qc(f);
+ struct usb_composite_dev *cdev = f->config->cdev;
+
+ /* Control interface has only altsetting 0 */
+ if (intf == ecm->ctrl_id) {
+ if (alt != 0)
+ goto fail;
+
+ if (ecm->notify->driver_data) {
+ VDBG(cdev, "reset ecm control %d\n", intf);
+ usb_ep_disable(ecm->notify);
+ }
+ if (!(ecm->notify->desc)) {
+ VDBG(cdev, "init ecm ctrl %d\n", intf);
+ if (config_ep_by_speed(cdev->gadget, f, ecm->notify))
+ goto fail;
+ }
+ usb_ep_enable(ecm->notify);
+ ecm->notify->driver_data = ecm;
+
+ /* Data interface has two altsettings, 0 and 1 */
+ } else if (intf == ecm->data_id) {
+ if (alt > 1)
+ goto fail;
+
+ if (ecm->port.in_ep->driver_data) {
+ DBG(cdev, "reset ecm\n");
+ gether_qc_disconnect(&ecm->port);
+ ecm_qc_bam_disconnect(ecm);
+ }
+
+ if (!ecm->port.in_ep->desc ||
+ !ecm->port.out_ep->desc) {
+ DBG(cdev, "init ecm\n");
+ if (config_ep_by_speed(cdev->gadget, f,
+ ecm->port.in_ep) ||
+ config_ep_by_speed(cdev->gadget, f,
+ ecm->port.out_ep)) {
+ ecm->port.in_ep->desc = NULL;
+ ecm->port.out_ep->desc = NULL;
+ goto fail;
+ }
+ }
+
+ /* CDC Ethernet only sends data in non-default altsettings.
+ * Changing altsettings resets filters, statistics, etc.
+ */
+ if (alt == 1) {
+ struct net_device *net;
+
+ /* Enable zlps by default for ECM conformance;
+ * override for musb_hdrc (avoids txdma ovhead).
+ */
+ ecm->port.is_zlp_ok = !(gadget_is_musbhdrc(cdev->gadget)
+ );
+ ecm->port.cdc_filter = DEFAULT_FILTER;
+ DBG(cdev, "activate ecm\n");
+ net = gether_qc_connect(&ecm->port);
+ if (IS_ERR(net))
+ return PTR_ERR(net);
+
+ if (ecm_qc_bam_connect(ecm))
+ goto fail;
+ }
+
+ /* NOTE this can be a minor disagreement with the ECM spec,
+ * which says speed notifications will "always" follow
+ * connection notifications. But we allow one connect to
+ * follow another (if the first is in flight), and instead
+ * just guarantee that a speed notification is always sent.
+ */
+ ecm_qc_notify(ecm);
+ } else
+ goto fail;
+
+ return 0;
+fail:
+ return -EINVAL;
+}
+
+/* Because the data interface supports multiple altsettings,
+ * this ECM function *MUST* implement a get_alt() method.
+ */
+static int ecm_qc_get_alt(struct usb_function *f, unsigned intf)
+{
+ struct f_ecm_qc *ecm = func_to_ecm_qc(f);
+
+ if (intf == ecm->ctrl_id)
+ return 0;
+ return ecm->port.in_ep->driver_data ? 1 : 0;
+}
+
+static void ecm_qc_disable(struct usb_function *f)
+{
+ struct f_ecm_qc *ecm = func_to_ecm_qc(f);
+
+ DBG(cdev, "ecm deactivated\n");
+
+ if (ecm->port.in_ep->driver_data) {
+ gether_qc_disconnect(&ecm->port);
+ ecm_qc_bam_disconnect(ecm);
+ }
+
+ if (ecm->notify->driver_data) {
+ usb_ep_disable(ecm->notify);
+ ecm->notify->driver_data = NULL;
+ ecm->notify->desc = NULL;
+ }
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Callbacks let us notify the host about connect/disconnect when the
+ * net device is opened or closed.
+ *
+ * For testing, note that link states on this side include both opened
+ * and closed variants of:
+ *
+ * - disconnected/unconfigured
+ * - configured but inactive (data alt 0)
+ * - configured and active (data alt 1)
+ *
+ * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
+ * SET_INTERFACE (altsetting). Remember also that "configured" doesn't
+ * imply the host is actually polling the notification endpoint, and
+ * likewise that "active" doesn't imply it's actually using the data
+ * endpoints for traffic.
+ */
+
+static void ecm_qc_open(struct qc_gether *geth)
+{
+ struct f_ecm_qc *ecm = func_to_ecm_qc(&geth->func);
+ DBG(ecm->port.func.config->cdev, "%s\n", __func__);
+
+ ecm->is_open = true;
+ ecm_qc_notify(ecm);
+}
+
+static void ecm_qc_close(struct qc_gether *geth)
+{
+ struct f_ecm_qc *ecm = func_to_ecm_qc(&geth->func);
+
+ DBG(ecm->port.func.config->cdev, "%s\n", __func__);
+
+ ecm->is_open = false;
+ ecm_qc_notify(ecm);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* ethernet function driver setup/binding */
+
+static int
+ecm_qc_bind(struct usb_configuration *c, struct usb_function *f)
+{
+ struct usb_composite_dev *cdev = c->cdev;
+ struct f_ecm_qc *ecm = func_to_ecm_qc(f);
+ int status;
+ struct usb_ep *ep;
+
+ /* allocate instance-specific interface IDs */
+ status = usb_interface_id(c, f);
+ if (status < 0)
+ goto fail;
+ ecm->ctrl_id = status;
+
+ ecm_qc_control_intf.bInterfaceNumber = status;
+ ecm_qc_union_desc.bMasterInterface0 = status;
+
+ status = usb_interface_id(c, f);
+ if (status < 0)
+ goto fail;
+ ecm->data_id = status;
+
+ ecm_qc_data_nop_intf.bInterfaceNumber = status;
+ ecm_qc_data_intf.bInterfaceNumber = status;
+ ecm_qc_union_desc.bSlaveInterface0 = status;
+
+ status = -ENODEV;
+
+ /* allocate instance-specific endpoints */
+ ep = usb_ep_autoconfig(cdev->gadget, &ecm_qc_fs_in_desc);
+ if (!ep)
+ goto fail;
+
+ ecm->port.in_ep = ep;
+ ep->driver_data = cdev; /* claim */
+
+ ep = usb_ep_autoconfig(cdev->gadget, &ecm_qc_fs_out_desc);
+ if (!ep)
+ goto fail;
+
+ ecm->port.out_ep = ep;
+ ep->driver_data = cdev; /* claim */
+
+ /* NOTE: a status/notification endpoint is *OPTIONAL* but we
+ * don't treat it that way. It's simpler, and some newer CDC
+ * profiles (wireless handsets) no longer treat it as optional.
+ */
+ ep = usb_ep_autoconfig(cdev->gadget, &ecm_qc_fs_notify_desc);
+ if (!ep)
+ goto fail;
+ ecm->notify = ep;
+ ep->driver_data = cdev; /* claim */
+
+ status = -ENOMEM;
+
+ /* allocate notification request and buffer */
+ ecm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
+ if (!ecm->notify_req)
+ goto fail;
+ ecm->notify_req->buf = kmalloc(ECM_QC_STATUS_BYTECOUNT, GFP_KERNEL);
+ if (!ecm->notify_req->buf)
+ goto fail;
+ ecm->notify_req->context = ecm;
+ ecm->notify_req->complete = ecm_qc_notify_complete;
+
+ /* copy descriptors, and track endpoint copies */
+ f->descriptors = usb_copy_descriptors(ecm_qc_fs_function);
+ if (!f->descriptors)
+ goto fail;
+
+ /* support all relevant hardware speeds... we expect that when
+ * hardware is dual speed, all bulk-capable endpoints work at
+ * both speeds
+ */
+ if (gadget_is_dualspeed(c->cdev->gadget)) {
+ ecm_qc_hs_in_desc.bEndpointAddress =
+ ecm_qc_fs_in_desc.bEndpointAddress;
+ ecm_qc_hs_out_desc.bEndpointAddress =
+ ecm_qc_fs_out_desc.bEndpointAddress;
+ ecm_qc_hs_notify_desc.bEndpointAddress =
+ ecm_qc_fs_notify_desc.bEndpointAddress;
+
+ /* copy descriptors, and track endpoint copies */
+ f->hs_descriptors = usb_copy_descriptors(ecm_qc_hs_function);
+ if (!f->hs_descriptors)
+ goto fail;
+ }
+
+ /* NOTE: all that is done without knowing or caring about
+ * the network link ... which is unavailable to this code
+ * until we're activated via set_alt().
+ */
+
+ ecm->port.open = ecm_qc_open;
+ ecm->port.close = ecm_qc_close;
+
+ DBG(cdev, "CDC Ethernet: %s speed IN/%s OUT/%s NOTIFY/%s\n",
+ gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
+ ecm->port.in_ep->name, ecm->port.out_ep->name,
+ ecm->notify->name);
+ return 0;
+
+fail:
+ if (f->descriptors)
+ usb_free_descriptors(f->descriptors);
+
+ if (ecm->notify_req) {
+ kfree(ecm->notify_req->buf);
+ usb_ep_free_request(ecm->notify, ecm->notify_req);
+ }
+
+ /* we might as well release our claims on endpoints */
+ if (ecm->notify)
+ ecm->notify->driver_data = NULL;
+ if (ecm->port.out_ep->desc)
+ ecm->port.out_ep->driver_data = NULL;
+ if (ecm->port.in_ep->desc)
+ ecm->port.in_ep->driver_data = NULL;
+
+ pr_err("%s: can't bind, err %d\n", f->name, status);
+
+ return status;
+}
+
+static void
+ecm_qc_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+ struct f_ecm_qc *ecm = func_to_ecm_qc(f);
+
+ DBG(c->cdev, "ecm unbind\n");
+
+ if (gadget_is_dualspeed(c->cdev->gadget))
+ usb_free_descriptors(f->hs_descriptors);
+ usb_free_descriptors(f->descriptors);
+
+ kfree(ecm->notify_req->buf);
+ usb_ep_free_request(ecm->notify, ecm->notify_req);
+
+ ecm_qc_string_defs[1].s = NULL;
+ kfree(ecm);
+}
+
+/**
+ * ecm_qc_bind_config - add CDC Ethernet network link to a configuration
+ * @c: the configuration to support the network link
+ * @ethaddr: a buffer in which the ethernet address of the host side
+ * side of the link was recorded
+ * Context: single threaded during gadget setup
+ *
+ * Returns zero on success, else negative errno.
+ *
+ * Caller must have called @gether_qc_setup(). Caller is also responsible
+ * for calling @gether_cleanup() before module unload.
+ */
+int
+ecm_qc_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
+{
+ struct f_ecm_qc *ecm;
+ int status;
+
+ if (!can_support_ecm(c->cdev->gadget) || !ethaddr)
+ return -EINVAL;
+
+ status = ecm_qc_bam_setup();
+ if (status) {
+ pr_err("bam setup failed");
+ return status;
+ }
+
+ /* maybe allocate device-global string IDs */
+ if (ecm_qc_string_defs[0].id == 0) {
+
+ /* control interface label */
+ status = usb_string_id(c->cdev);
+ if (status < 0)
+ return status;
+ ecm_qc_string_defs[0].id = status;
+ ecm_qc_control_intf.iInterface = status;
+
+ /* data interface label */
+ status = usb_string_id(c->cdev);
+ if (status < 0)
+ return status;
+ ecm_qc_string_defs[2].id = status;
+ ecm_qc_data_intf.iInterface = status;
+
+ /* MAC address */
+ status = usb_string_id(c->cdev);
+ if (status < 0)
+ return status;
+ ecm_qc_string_defs[1].id = status;
+ ecm_qc_desc.iMACAddress = status;
+ }
+
+ /* allocate and initialize one new instance */
+ ecm = kzalloc(sizeof *ecm, GFP_KERNEL);
+ if (!ecm)
+ return -ENOMEM;
+
+ /* export host's Ethernet address in CDC format */
+ snprintf(ecm->ethaddr, sizeof ecm->ethaddr,
+ "%02X%02X%02X%02X%02X%02X",
+ ethaddr[0], ethaddr[1], ethaddr[2],
+ ethaddr[3], ethaddr[4], ethaddr[5]);
+ ecm_qc_string_defs[1].s = ecm->ethaddr;
+
+ ecm->port.cdc_filter = DEFAULT_FILTER;
+
+ ecm->port.func.name = "cdc_ethernet";
+ ecm->port.func.strings = ecm_qc_strings;
+ /* descriptors are per-instance copies */
+ ecm->port.func.bind = ecm_qc_bind;
+ ecm->port.func.unbind = ecm_qc_unbind;
+ ecm->port.func.set_alt = ecm_qc_set_alt;
+ ecm->port.func.get_alt = ecm_qc_get_alt;
+ ecm->port.func.setup = ecm_qc_setup;
+ ecm->port.func.disable = ecm_qc_disable;
+
+ status = usb_add_function(c, &ecm->port.func);
+ if (status) {
+ ecm_qc_string_defs[1].s = NULL;
+ kfree(ecm);
+ }
+ return status;
+}