diff options
Diffstat (limited to 'drivers/net/usb/huawei_cdc_ncm.c')
| -rw-r--r-- | drivers/net/usb/huawei_cdc_ncm.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/drivers/net/usb/huawei_cdc_ncm.c b/drivers/net/usb/huawei_cdc_ncm.c new file mode 100644 index 000000000..849b77330 --- /dev/null +++ b/drivers/net/usb/huawei_cdc_ncm.c @@ -0,0 +1,227 @@ +// 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; + 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; + + /* For many Huawei devices the NTB32 mode is the default and the best mode + * they work with. Huawei E5785 and E5885 devices refuse to work in NTB16 mode at all. + */ + drvflags |= CDC_NCM_FLAG_PREFER_NTB32; + + 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 */ + WWAN_PORT_AT, + 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"); |