// SPDX-License-Identifier: GPL-2.0 /* * Intel USBIO Bridge driver * * Copyright (c) 2025 Intel Corporation. * Copyright (c) 2025 Red Hat, Inc. */ #include #include #include #include #include #include #include #include #include #include #include #include #include /************************************* * USBIO Bridge Protocol Definitions * *************************************/ /* USBIO Control Commands */ #define USBIO_CTRLCMD_PROTVER 0 #define USBIO_CTRLCMD_FWVER 1 #define USBIO_CTRLCMD_HS 2 #define USBIO_CTRLCMD_ENUMGPIO 16 #define USBIO_CTRLCMD_ENUMI2C 17 /* USBIO Packet Flags */ #define USBIO_PKTFLAG_ACK BIT(0) #define USBIO_PKTFLAG_RSP BIT(1) #define USBIO_PKTFLAG_CMP BIT(2) #define USBIO_PKTFLAG_ERR BIT(3) #define USBIO_PKTFLAGS_REQRESP (USBIO_PKTFLAG_CMP | USBIO_PKTFLAG_ACK) #define USBIO_CTRLXFER_TIMEOUT 0 #define USBIO_BULKXFER_TIMEOUT 100 struct usbio_protver { u8 ver; } __packed; struct usbio_fwver { u8 major; u8 minor; __le16 patch; __le16 build; } __packed; /*********************************** * USBIO Bridge Device Definitions * ***********************************/ /** * struct usbio_device - the usb device exposing IOs * * @dev: the device in the usb interface * @udev: the detected usb device * @intf: the usb interface * @quirks: quirks * @ctrl_mutex: protects ctrl_buf * @ctrl_pipe: the control transfer pipe * @ctrlbuf_len: the size of the control transfer pipe * @ctrlbuf: the buffer used for control transfers * @bulk_mutex: protects tx_buf, rx_buf and split bulk-transfers getting interrupted * @tx_pipe: the bulk out pipe * @txbuf_len: the size of the bulk out pipe * @txbuf: the buffer used for bulk out transfers * @rx_pipe: the bulk in pipe * @rxbuf_len: the size of the bulk in pipe * @rxdat_len: the data length at rx buffer * @rxbuf: the buffer used for bulk in transfers * @urb: the urb to read bulk pipe * @done: completion object as request is done * @cli_list: device's client list * @nr_gpio_banks: Number of GPIO banks * @gpios: GPIO bank descriptors * @nr_gpio_banks: Number of I2C busses * @gpios: I2C bank descriptors */ struct usbio_device { struct device *dev; struct usb_device *udev; struct usb_interface *intf; unsigned long quirks; struct mutex ctrl_mutex; unsigned int ctrl_pipe; u16 ctrlbuf_len; void *ctrlbuf; struct mutex bulk_mutex; unsigned int tx_pipe; u16 txbuf_len; void *txbuf; unsigned int rx_pipe; u16 rxbuf_len; u16 rxdat_len; void *rxbuf; struct urb *urb; struct completion done; struct list_head cli_list; unsigned int nr_gpio_banks; struct usbio_gpio_bank_desc gpios[USBIO_MAX_GPIOBANKS]; unsigned int nr_i2c_buses; struct usbio_i2c_bus_desc i2cs[USBIO_MAX_I2CBUSES]; }; /** * struct usbio_client - represents a usbio client * * @auxdev: auxiliary device object * @mutex: protects @bridge * @bridge: usbio bridge who service the client * @link: usbio bridge clients list member */ struct usbio_client { struct auxiliary_device auxdev; struct mutex mutex; struct usbio_device *bridge; struct list_head link; }; #define adev_to_client(adev) container_of_const(adev, struct usbio_client, auxdev) static int usbio_ctrl_msg(struct usbio_device *usbio, u8 type, u8 cmd, const void *obuf, u16 obuf_len, void *ibuf, u16 ibuf_len) { u8 request = USB_TYPE_VENDOR | USB_RECIP_DEVICE; struct usbio_ctrl_packet *cpkt; unsigned int pipe; u16 cpkt_len; int ret; lockdep_assert_held(&usbio->ctrl_mutex); if ((obuf_len > (usbio->ctrlbuf_len - sizeof(*cpkt))) || (ibuf_len > (usbio->ctrlbuf_len - sizeof(*cpkt)))) return -EMSGSIZE; /* Prepare Control Packet Header */ cpkt = usbio->ctrlbuf; cpkt->header.type = type; cpkt->header.cmd = cmd; if (type == USBIO_PKTTYPE_CTRL || ibuf_len) cpkt->header.flags = USBIO_PKTFLAGS_REQRESP; else cpkt->header.flags = USBIO_PKTFLAG_CMP; cpkt->len = obuf_len; /* Copy the data */ memcpy(cpkt->data, obuf, obuf_len); pipe = usb_sndctrlpipe(usbio->udev, usbio->ctrl_pipe); cpkt_len = sizeof(*cpkt) + obuf_len; ret = usb_control_msg(usbio->udev, pipe, 0, request | USB_DIR_OUT, 0, 0, cpkt, cpkt_len, USBIO_CTRLXFER_TIMEOUT); dev_dbg(usbio->dev, "control out %d hdr %*phN data %*phN\n", ret, (int)sizeof(*cpkt), cpkt, (int)cpkt->len, cpkt->data); if (ret != cpkt_len) { dev_err(usbio->dev, "USB control out failed: %d\n", ret); return (ret < 0) ? ret : -EPROTO; } if (!(cpkt->header.flags & USBIO_PKTFLAG_ACK)) return 0; pipe = usb_rcvctrlpipe(usbio->udev, usbio->ctrl_pipe); cpkt_len = sizeof(*cpkt) + ibuf_len; ret = usb_control_msg(usbio->udev, pipe, 0, request | USB_DIR_IN, 0, 0, cpkt, cpkt_len, USBIO_CTRLXFER_TIMEOUT); dev_dbg(usbio->dev, "control in %d hdr %*phN data %*phN\n", ret, (int)sizeof(*cpkt), cpkt, (int)cpkt->len, cpkt->data); if (ret < sizeof(*cpkt)) { dev_err(usbio->dev, "USB control in failed: %d\n", ret); return (ret < 0) ? ret : -EPROTO; } if (cpkt->header.type != type || cpkt->header.cmd != cmd || !(cpkt->header.flags & USBIO_PKTFLAG_RSP)) { dev_err(usbio->dev, "Unexpected reply type: %u, cmd: %u, flags: %u\n", cpkt->header.type, cpkt->header.cmd, cpkt->header.flags); return -EPROTO; } if (cpkt->header.flags & USBIO_PKTFLAG_ERR) return -EREMOTEIO; if (ibuf_len < cpkt->len) return -ENOSPC; memcpy(ibuf, cpkt->data, cpkt->len); return cpkt->len; } int usbio_control_msg(struct auxiliary_device *adev, u8 type, u8 cmd, const void *obuf, u16 obuf_len, void *ibuf, u16 ibuf_len) { struct usbio_client *client = adev_to_client(adev); struct usbio_device *usbio; int ret; guard(mutex)(&client->mutex); usbio = client->bridge; if (!usbio) return -ENODEV; /* Disconnected */ ret = usb_autopm_get_interface(usbio->intf); if (ret) return ret; mutex_lock(&usbio->ctrl_mutex); ret = usbio_ctrl_msg(client->bridge, type, cmd, obuf, obuf_len, ibuf, ibuf_len); mutex_unlock(&usbio->ctrl_mutex); usb_autopm_put_interface(usbio->intf); return ret; } EXPORT_SYMBOL_NS_GPL(usbio_control_msg, "USBIO"); static void usbio_bulk_recv(struct urb *urb) { struct usbio_bulk_packet *bpkt = urb->transfer_buffer; struct usbio_device *usbio = urb->context; if (!urb->status) { if (bpkt->header.flags & USBIO_PKTFLAG_RSP) { usbio->rxdat_len = urb->actual_length; complete(&usbio->done); } } else if (urb->status != -ENOENT) { dev_err(usbio->dev, "Bulk in error %d\n", urb->status); } usb_submit_urb(usbio->urb, GFP_ATOMIC); } int usbio_bulk_msg(struct auxiliary_device *adev, u8 type, u8 cmd, bool last, const void *obuf, u16 obuf_len, void *ibuf, u16 ibuf_len) { struct usbio_client *client = adev_to_client(adev); struct usbio_device *usbio = client->bridge; struct usbio_bulk_packet *bpkt; int ret, act = 0; u16 bpkt_len; lockdep_assert_held(&client->mutex); lockdep_assert_held(&usbio->bulk_mutex); if ((obuf_len > (usbio->txbuf_len - sizeof(*bpkt))) || (ibuf_len > (usbio->txbuf_len - sizeof(*bpkt)))) return -EMSGSIZE; if (ibuf_len) reinit_completion(&usbio->done); /* If no data to send, skip to read */ if (!obuf_len) goto read; /* Prepare Bulk Packet Header */ bpkt = usbio->txbuf; bpkt->header.type = type; bpkt->header.cmd = cmd; if (!last) bpkt->header.flags = 0; else if (ibuf_len) bpkt->header.flags = USBIO_PKTFLAGS_REQRESP; else bpkt->header.flags = USBIO_PKTFLAG_CMP; bpkt->len = cpu_to_le16(obuf_len); /* Copy the data */ memcpy(bpkt->data, obuf, obuf_len); bpkt_len = sizeof(*bpkt) + obuf_len; ret = usb_bulk_msg(usbio->udev, usbio->tx_pipe, bpkt, bpkt_len, &act, USBIO_BULKXFER_TIMEOUT); dev_dbg(usbio->dev, "bulk out %d hdr %*phN data %*phN\n", act, (int)sizeof(*bpkt), bpkt, obuf_len, bpkt->data); if (ret || act != bpkt_len) { dev_err(usbio->dev, "Bulk out failed: %d\n", ret); return ret ?: -EPROTO; } if (!(bpkt->header.flags & USBIO_PKTFLAG_ACK)) return obuf_len; read: ret = wait_for_completion_timeout(&usbio->done, USBIO_BULKXFER_TIMEOUT); if (ret <= 0) { dev_err(usbio->dev, "Bulk in wait failed: %d\n", ret); return ret ?: -ETIMEDOUT; } act = usbio->rxdat_len; bpkt = usbio->rxbuf; bpkt_len = le16_to_cpu(bpkt->len); dev_dbg(usbio->dev, "bulk in %d hdr %*phN data %*phN\n", act, (int)sizeof(*bpkt), bpkt, bpkt_len, bpkt->data); /* * Unsupported bulk commands get only an usbio_packet_header with * the error flag set as reply. Return -EPIPE for this case. */ if (act == sizeof(struct usbio_packet_header) && (bpkt->header.flags & USBIO_PKTFLAG_ERR)) return -EPIPE; if (act < sizeof(*bpkt)) { dev_err(usbio->dev, "Bulk in short read: %d\n", act); return -EPROTO; } if (bpkt->header.type != type || bpkt->header.cmd != cmd || !(bpkt->header.flags & USBIO_PKTFLAG_RSP)) { dev_err(usbio->dev, "Unexpected bulk in type 0x%02x cmd 0x%02x flags 0x%02x\n", bpkt->header.type, bpkt->header.cmd, bpkt->header.flags); return -EPROTO; } if (bpkt->header.flags & USBIO_PKTFLAG_ERR) return -EREMOTEIO; if (ibuf_len < bpkt_len) return -ENOSPC; memcpy(ibuf, bpkt->data, bpkt_len); return bpkt_len; } EXPORT_SYMBOL_NS_GPL(usbio_bulk_msg, "USBIO"); int usbio_acquire(struct auxiliary_device *adev) { struct usbio_client *client = adev_to_client(adev); struct usbio_device *usbio; int ret; mutex_lock(&client->mutex); usbio = client->bridge; if (!usbio) { ret = -ENODEV; /* Disconnected */ goto err_unlock; } ret = usb_autopm_get_interface(usbio->intf); if (ret) goto err_unlock; mutex_lock(&usbio->bulk_mutex); /* Leave client locked until release to avoid abba deadlock issues */ return 0; err_unlock: mutex_unlock(&client->mutex); return ret; } EXPORT_SYMBOL_NS_GPL(usbio_acquire, "USBIO"); void usbio_release(struct auxiliary_device *adev) { struct usbio_client *client = adev_to_client(adev); struct usbio_device *usbio = client->bridge; lockdep_assert_held(&client->mutex); mutex_unlock(&usbio->bulk_mutex); usb_autopm_put_interface(usbio->intf); mutex_unlock(&client->mutex); } EXPORT_SYMBOL_NS_GPL(usbio_release, "USBIO"); void usbio_get_txrxbuf_len(struct auxiliary_device *adev, u16 *txbuf_len, u16 *rxbuf_len) { struct usbio_client *client = adev_to_client(adev); struct usbio_device *usbio; guard(mutex)(&client->mutex); usbio = client->bridge; if (!usbio) return; /* Disconnected */ *txbuf_len = usbio->txbuf_len; *rxbuf_len = usbio->rxbuf_len; } EXPORT_SYMBOL_NS_GPL(usbio_get_txrxbuf_len, "USBIO"); unsigned long usbio_get_quirks(struct auxiliary_device *adev) { struct usbio_client *client = adev_to_client(adev); struct usbio_device *usbio; guard(mutex)(&client->mutex); usbio = client->bridge; if (!usbio) return 0; /* Disconnected */ return usbio->quirks; } EXPORT_SYMBOL_NS_GPL(usbio_get_quirks, "USBIO"); static void usbio_auxdev_release(struct device *dev) { struct auxiliary_device *adev = to_auxiliary_dev(dev); struct usbio_client *client = adev_to_client(adev); mutex_destroy(&client->mutex); kfree(client); } static int usbio_add_client(struct usbio_device *usbio, char *name, u8 id, void *data) { struct usbio_client *client; struct auxiliary_device *adev; int ret; client = kzalloc(sizeof(*client), GFP_KERNEL); if (!client) return -ENOMEM; mutex_init(&client->mutex); client->bridge = usbio; adev = &client->auxdev; adev->name = name; adev->id = id; adev->dev.parent = usbio->dev; adev->dev.platform_data = data; adev->dev.release = usbio_auxdev_release; ret = auxiliary_device_init(adev); if (ret) { usbio_auxdev_release(&adev->dev); return ret; } ret = auxiliary_device_add(adev); if (ret) { auxiliary_device_uninit(adev); return ret; } list_add_tail(&client->link, &usbio->cli_list); return 0; } static int usbio_enum_gpios(struct usbio_device *usbio) { struct usbio_gpio_bank_desc *gpio = usbio->gpios; dev_dbg(usbio->dev, "GPIO Banks: %d\n", usbio->nr_gpio_banks); for (unsigned int i = 0; i < usbio->nr_gpio_banks; i++) dev_dbg(usbio->dev, "\tBank%d[%d] map: %#08x\n", gpio[i].id, gpio[i].pins, gpio[i].bmap); usbio_add_client(usbio, USBIO_GPIO_CLIENT, 0, gpio); return 0; } static int usbio_enum_i2cs(struct usbio_device *usbio) { struct usbio_i2c_bus_desc *i2c = usbio->i2cs; dev_dbg(usbio->dev, "I2C Busses: %d\n", usbio->nr_i2c_buses); for (unsigned int i = 0; i < usbio->nr_i2c_buses; i++) { dev_dbg(usbio->dev, "\tBus%d caps: %#02x\n", i2c[i].id, i2c[i].caps); usbio_add_client(usbio, USBIO_I2C_CLIENT, i, &i2c[i]); } return 0; } static int usbio_suspend(struct usb_interface *intf, pm_message_t msg) { struct usbio_device *usbio = usb_get_intfdata(intf); usb_kill_urb(usbio->urb); return 0; } static int usbio_resume(struct usb_interface *intf) { struct usbio_device *usbio = usb_get_intfdata(intf); return usb_submit_urb(usbio->urb, GFP_KERNEL); } static void usbio_disconnect(struct usb_interface *intf) { struct usbio_device *usbio = usb_get_intfdata(intf); struct usbio_client *client; /* Wakeup any clients waiting for a reply */ usbio->rxdat_len = 0; complete(&usbio->done); /* Let clients know the bridge is gone */ list_for_each_entry(client, &usbio->cli_list, link) { mutex_lock(&client->mutex); client->bridge = NULL; mutex_unlock(&client->mutex); } /* From here on clients will no longer touch struct usbio_device */ usb_kill_urb(usbio->urb); usb_free_urb(usbio->urb); list_for_each_entry_reverse(client, &usbio->cli_list, link) { auxiliary_device_delete(&client->auxdev); auxiliary_device_uninit(&client->auxdev); } } static int usbio_probe(struct usb_interface *intf, const struct usb_device_id *id) { struct usb_device *udev = interface_to_usbdev(intf); struct usb_endpoint_descriptor *ep_in, *ep_out; struct device *dev = &intf->dev; struct usbio_protver protver; struct usbio_device *usbio; struct usbio_fwver fwver; int ret; usbio = devm_kzalloc(dev, sizeof(*usbio), GFP_KERNEL); if (!usbio) return -ENOMEM; ret = devm_mutex_init(dev, &usbio->ctrl_mutex); if (ret) return ret; ret = devm_mutex_init(dev, &usbio->bulk_mutex); if (ret) return ret; usbio->dev = dev; usbio->udev = udev; usbio->intf = intf; usbio->quirks = id ? id->driver_info : 0; init_completion(&usbio->done); INIT_LIST_HEAD(&usbio->cli_list); usb_set_intfdata(intf, usbio); usbio->ctrl_pipe = usb_endpoint_num(&udev->ep0.desc); usbio->ctrlbuf_len = usb_maxpacket(udev, usbio->ctrl_pipe); usbio->ctrlbuf = devm_kzalloc(dev, usbio->ctrlbuf_len, GFP_KERNEL); if (!usbio->ctrlbuf) return -ENOMEM; /* Find the first bulk-in and bulk-out endpoints */ ret = usb_find_common_endpoints(intf->cur_altsetting, &ep_in, &ep_out, NULL, NULL); if (ret) { dev_err(dev, "Cannot find bulk endpoints: %d\n", ret); return ret; } usbio->tx_pipe = usb_sndbulkpipe(udev, usb_endpoint_num(ep_out)); if (usbio->quirks & USBIO_QUIRK_BULK_MAXP_63) usbio->txbuf_len = 63; else usbio->txbuf_len = usb_endpoint_maxp(ep_out); usbio->txbuf = devm_kzalloc(dev, usbio->txbuf_len, GFP_KERNEL); if (!usbio->txbuf) return -ENOMEM; usbio->rx_pipe = usb_rcvbulkpipe(udev, usb_endpoint_num(ep_in)); if (usbio->quirks & USBIO_QUIRK_BULK_MAXP_63) usbio->rxbuf_len = 63; else usbio->rxbuf_len = usb_endpoint_maxp(ep_in); usbio->rxbuf = devm_kzalloc(dev, usbio->rxbuf_len, GFP_KERNEL); if (!usbio->rxbuf) return -ENOMEM; usbio->urb = usb_alloc_urb(0, GFP_KERNEL); if (!usbio->urb) return -ENOMEM; usb_fill_bulk_urb(usbio->urb, udev, usbio->rx_pipe, usbio->rxbuf, usbio->rxbuf_len, usbio_bulk_recv, usbio); ret = usb_submit_urb(usbio->urb, GFP_KERNEL); if (ret) return dev_err_probe(dev, ret, "Submitting usb urb\n"); mutex_lock(&usbio->ctrl_mutex); ret = usbio_ctrl_msg(usbio, USBIO_PKTTYPE_CTRL, USBIO_CTRLCMD_HS, NULL, 0, NULL, 0); if (ret < 0) goto err_unlock; ret = usbio_ctrl_msg(usbio, USBIO_PKTTYPE_CTRL, USBIO_CTRLCMD_PROTVER, NULL, 0, &protver, sizeof(protver)); if (ret < 0) goto err_unlock; ret = usbio_ctrl_msg(usbio, USBIO_PKTTYPE_CTRL, USBIO_CTRLCMD_FWVER, NULL, 0, &fwver, sizeof(fwver)); if (ret < 0) goto err_unlock; ret = usbio_ctrl_msg(usbio, USBIO_PKTTYPE_CTRL, USBIO_CTRLCMD_ENUMGPIO, NULL, 0, usbio->gpios, sizeof(usbio->gpios)); if (ret < 0 || ret % sizeof(struct usbio_gpio_bank_desc)) { ret = (ret < 0) ? ret : -EPROTO; goto err_unlock; } usbio->nr_gpio_banks = ret / sizeof(struct usbio_gpio_bank_desc); ret = usbio_ctrl_msg(usbio, USBIO_PKTTYPE_CTRL, USBIO_CTRLCMD_ENUMI2C, NULL, 0, usbio->i2cs, sizeof(usbio->i2cs)); if (ret < 0 || ret % sizeof(struct usbio_i2c_bus_desc)) { ret = (ret < 0) ? ret : -EPROTO; goto err_unlock; } usbio->nr_i2c_buses = ret / sizeof(struct usbio_i2c_bus_desc); mutex_unlock(&usbio->ctrl_mutex); dev_dbg(dev, "ProtVer(BCD): %02x FwVer: %d.%d.%d.%d\n", protver.ver, fwver.major, fwver.minor, le16_to_cpu(fwver.patch), le16_to_cpu(fwver.build)); usbio_enum_gpios(usbio); usbio_enum_i2cs(usbio); return 0; err_unlock: mutex_unlock(&usbio->ctrl_mutex); usb_kill_urb(usbio->urb); usb_free_urb(usbio->urb); return ret; } static const struct usb_device_id usbio_table[] = { { USB_DEVICE(0x2ac1, 0x20c1), /* Lattice NX40 */ .driver_info = USBIO_QUIRK_I2C_MAX_RW_LEN_52 }, { USB_DEVICE(0x2ac1, 0x20c9), /* Lattice NX33 */ .driver_info = USBIO_QUIRK_I2C_NO_INIT_ACK | USBIO_QUIRK_I2C_MAX_RW_LEN_52 | USBIO_QUIRK_I2C_ALLOW_400KHZ }, { USB_DEVICE(0x2ac1, 0x20cb) }, /* Lattice NX33U */ { USB_DEVICE(0x06cb, 0x0701), /* Synaptics Sabre */ .driver_info = USBIO_QUIRK_BULK_MAXP_63 | USBIO_QUIRK_I2C_USE_CHUNK_LEN }, { } }; MODULE_DEVICE_TABLE(usb, usbio_table); static struct usb_driver usbio_driver = { .name = "usbio-bridge", .probe = usbio_probe, .disconnect = usbio_disconnect, .suspend = usbio_suspend, .resume = usbio_resume, .id_table = usbio_table, .supports_autosuspend = 1, }; module_usb_driver(usbio_driver); struct usbio_match_ids_walk_data { struct acpi_device *adev; const struct acpi_device_id *hids; unsigned int id; }; static int usbio_match_device_ids(struct acpi_device *adev, void *data) { struct usbio_match_ids_walk_data *wd = data; unsigned int id = 0; char *uid; if (acpi_match_device_ids(adev, wd->hids)) return 0; uid = acpi_device_uid(adev); if (uid) { for (int i = 0; i < strlen(uid); i++) { if (!kstrtouint(&uid[i], 10, &id)) break; } } if (!uid || wd->id == id) { wd->adev = adev; return 1; } return 0; } void usbio_acpi_bind(struct auxiliary_device *adev, const struct acpi_device_id *hids) { struct device *dev = &adev->dev; struct acpi_device *parent; struct usbio_match_ids_walk_data wd = { .adev = NULL, .hids = hids, .id = adev->id, }; parent = ACPI_COMPANION(dev->parent); if (!parent) return; acpi_dev_for_each_child(parent, usbio_match_device_ids, &wd); if (wd.adev) ACPI_COMPANION_SET(dev, wd.adev); } EXPORT_SYMBOL_NS_GPL(usbio_acpi_bind, "USBIO"); MODULE_DESCRIPTION("Intel USBIO Bridge driver"); MODULE_AUTHOR("Israel Cepeda "); MODULE_AUTHOR("Hans de Goede "); MODULE_LICENSE("GPL");