| // SPDX-License-Identifier: GPL-2.0-only |
| /* huawei_cdc_ncm.c - handles Huawei devices using the CDC NCM protocol as |
| * transport layer. |
| * Copyright (C) 2013 Enrico Mioso <mrkiko.rs@gmail.com> |
| * |
| * ABSTRACT: |
| * This driver handles devices resembling the CDC NCM standard, but |
| * encapsulating another protocol inside it. An example are some Huawei 3G |
| * devices, exposing an embedded AT channel where you can set up the NCM |
| * connection. |
| * This code has been heavily inspired by the cdc_mbim.c driver, which is |
| * Copyright (c) 2012 Smith Micro Software, Inc. |
| * Copyright (c) 2012 Bjørn Mork <bjorn@mork.no> |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/netdevice.h> |
| #include <linux/ethtool.h> |
| #include <linux/if_vlan.h> |
| #include <linux/ip.h> |
| #include <linux/mii.h> |
| #include <linux/usb.h> |
| #include <linux/usb/cdc.h> |
| #include <linux/usb/usbnet.h> |
| #include <linux/usb/cdc-wdm.h> |
| #include <linux/usb/cdc_ncm.h> |
| |
| /* Driver data */ |
| struct huawei_cdc_ncm_state { |
| struct cdc_ncm_ctx *ctx; |
| atomic_t pmcount; |
| struct usb_driver *subdriver; |
| struct usb_interface *control; |
| struct usb_interface *data; |
| }; |
| |
| static int huawei_cdc_ncm_manage_power(struct usbnet *usbnet_dev, int on) |
| { |
| struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data; |
| int rv; |
| |
| if ((on && atomic_add_return(1, &drvstate->pmcount) == 1) || |
| (!on && atomic_dec_and_test(&drvstate->pmcount))) { |
| rv = usb_autopm_get_interface(usbnet_dev->intf); |
| usbnet_dev->intf->needs_remote_wakeup = on; |
| if (!rv) |
| usb_autopm_put_interface(usbnet_dev->intf); |
| } |
| return 0; |
| } |
| |
| static int huawei_cdc_ncm_wdm_manage_power(struct usb_interface *intf, |
| int status) |
| { |
| struct usbnet *usbnet_dev = usb_get_intfdata(intf); |
| |
| /* can be called while disconnecting */ |
| if (!usbnet_dev) |
| return 0; |
| |
| return huawei_cdc_ncm_manage_power(usbnet_dev, status); |
| } |
| |
| |
| static int huawei_cdc_ncm_bind(struct usbnet *usbnet_dev, |
| struct usb_interface *intf) |
| { |
| struct cdc_ncm_ctx *ctx; |
| struct usb_driver *subdriver = ERR_PTR(-ENODEV); |
| int ret = -ENODEV; |
| struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data; |
| int drvflags = 0; |
| |
| /* altsetting should always be 1 for NCM devices - so we hard-coded |
| * it here. Some huawei devices will need the NDP part of the NCM package to |
| * be at the end of the frame. |
| */ |
| drvflags |= CDC_NCM_FLAG_NDP_TO_END; |
| |
| /* Additionally, it has been reported that some Huawei E3372H devices, with |
| * firmware version 21.318.01.00.541, come out of reset in NTB32 format mode, hence |
| * needing to be set to the NTB16 one again. |
| */ |
| drvflags |= CDC_NCM_FLAG_RESET_NTB16; |
| ret = cdc_ncm_bind_common(usbnet_dev, intf, 1, drvflags); |
| if (ret) |
| goto err; |
| |
| ctx = drvstate->ctx; |
| |
| if (usbnet_dev->status) |
| /* The wMaxCommand buffer must be big enough to hold |
| * any message from the modem. Experience has shown |
| * that some replies are more than 256 bytes long |
| */ |
| subdriver = usb_cdc_wdm_register(ctx->control, |
| &usbnet_dev->status->desc, |
| 1024, /* wMaxCommand */ |
| huawei_cdc_ncm_wdm_manage_power); |
| if (IS_ERR(subdriver)) { |
| ret = PTR_ERR(subdriver); |
| cdc_ncm_unbind(usbnet_dev, intf); |
| goto err; |
| } |
| |
| /* Prevent usbnet from using the status descriptor */ |
| usbnet_dev->status = NULL; |
| |
| drvstate->subdriver = subdriver; |
| |
| err: |
| return ret; |
| } |
| |
| static void huawei_cdc_ncm_unbind(struct usbnet *usbnet_dev, |
| struct usb_interface *intf) |
| { |
| struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data; |
| struct cdc_ncm_ctx *ctx = drvstate->ctx; |
| |
| if (drvstate->subdriver && drvstate->subdriver->disconnect) |
| drvstate->subdriver->disconnect(ctx->control); |
| drvstate->subdriver = NULL; |
| |
| cdc_ncm_unbind(usbnet_dev, intf); |
| } |
| |
| static int huawei_cdc_ncm_suspend(struct usb_interface *intf, |
| pm_message_t message) |
| { |
| int ret = 0; |
| struct usbnet *usbnet_dev = usb_get_intfdata(intf); |
| struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data; |
| struct cdc_ncm_ctx *ctx = drvstate->ctx; |
| |
| if (ctx == NULL) { |
| ret = -ENODEV; |
| goto error; |
| } |
| |
| ret = usbnet_suspend(intf, message); |
| if (ret < 0) |
| goto error; |
| |
| if (intf == ctx->control && |
| drvstate->subdriver && |
| drvstate->subdriver->suspend) |
| ret = drvstate->subdriver->suspend(intf, message); |
| if (ret < 0) |
| usbnet_resume(intf); |
| |
| error: |
| return ret; |
| } |
| |
| static int huawei_cdc_ncm_resume(struct usb_interface *intf) |
| { |
| int ret = 0; |
| struct usbnet *usbnet_dev = usb_get_intfdata(intf); |
| struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data; |
| bool callsub; |
| struct cdc_ncm_ctx *ctx = drvstate->ctx; |
| |
| /* should we call subdriver's resume function? */ |
| callsub = |
| (intf == ctx->control && |
| drvstate->subdriver && |
| drvstate->subdriver->resume); |
| |
| if (callsub) |
| ret = drvstate->subdriver->resume(intf); |
| if (ret < 0) |
| goto err; |
| ret = usbnet_resume(intf); |
| if (ret < 0 && callsub) |
| drvstate->subdriver->suspend(intf, PMSG_SUSPEND); |
| err: |
| return ret; |
| } |
| |
| static const struct driver_info huawei_cdc_ncm_info = { |
| .description = "Huawei CDC NCM device", |
| .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN, |
| .bind = huawei_cdc_ncm_bind, |
| .unbind = huawei_cdc_ncm_unbind, |
| .manage_power = huawei_cdc_ncm_manage_power, |
| .rx_fixup = cdc_ncm_rx_fixup, |
| .tx_fixup = cdc_ncm_tx_fixup, |
| }; |
| |
| static const struct usb_device_id huawei_cdc_ncm_devs[] = { |
| /* Huawei NCM devices disguised as vendor specific */ |
| { USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x02, 0x16), |
| .driver_info = (unsigned long)&huawei_cdc_ncm_info, |
| }, |
| { USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x02, 0x46), |
| .driver_info = (unsigned long)&huawei_cdc_ncm_info, |
| }, |
| { USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x02, 0x76), |
| .driver_info = (unsigned long)&huawei_cdc_ncm_info, |
| }, |
| { USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x03, 0x16), |
| .driver_info = (unsigned long)&huawei_cdc_ncm_info, |
| }, |
| |
| /* Terminating entry */ |
| { |
| }, |
| }; |
| MODULE_DEVICE_TABLE(usb, huawei_cdc_ncm_devs); |
| |
| static struct usb_driver huawei_cdc_ncm_driver = { |
| .name = "huawei_cdc_ncm", |
| .id_table = huawei_cdc_ncm_devs, |
| .probe = usbnet_probe, |
| .disconnect = usbnet_disconnect, |
| .suspend = huawei_cdc_ncm_suspend, |
| .resume = huawei_cdc_ncm_resume, |
| .reset_resume = huawei_cdc_ncm_resume, |
| .supports_autosuspend = 1, |
| .disable_hub_initiated_lpm = 1, |
| }; |
| module_usb_driver(huawei_cdc_ncm_driver); |
| MODULE_AUTHOR("Enrico Mioso <mrkiko.rs@gmail.com>"); |
| MODULE_DESCRIPTION("USB CDC NCM host driver with encapsulated protocol support"); |
| MODULE_LICENSE("GPL"); |