// SPDX-License-Identifier: ISC
/*
 * Copyright (c) 2007-2011 Atheros Communications Inc.
 * Copyright (c) 2011-2012,2017 Qualcomm Atheros, Inc.
 * Copyright (c) 2016-2017 Erik Stromdahl <erik.stromdahl@gmail.com>
 */

#include <linux/module.h>
#include <linux/usb.h>

#include "debug.h"
#include "core.h"
#include "bmi.h"
#include "hif.h"
#include "htc.h"
#include "usb.h"

static void ath10k_usb_post_recv_transfers(struct ath10k *ar,
                                           struct ath10k_usb_pipe *recv_pipe);

/* inlined helper functions */

static inline enum ath10k_htc_ep_id
eid_from_htc_hdr(struct ath10k_htc_hdr *htc_hdr)
{
        return (enum ath10k_htc_ep_id)htc_hdr->eid;
}

static inline bool is_trailer_only_msg(struct ath10k_htc_hdr *htc_hdr)
{
        return __le16_to_cpu(htc_hdr->len) == htc_hdr->trailer_len;
}

/* pipe/urb operations */
static struct ath10k_urb_context *
ath10k_usb_alloc_urb_from_pipe(struct ath10k_usb_pipe *pipe)
{
        struct ath10k_urb_context *urb_context = NULL;
        unsigned long flags;

        /* bail if this pipe is not initialized */
        if (!pipe->ar_usb)
                return NULL;

        spin_lock_irqsave(&pipe->ar_usb->cs_lock, flags);
        if (!list_empty(&pipe->urb_list_head)) {
                urb_context = list_first_entry(&pipe->urb_list_head,
                                               struct ath10k_urb_context, link);
                list_del(&urb_context->link);
                pipe->urb_cnt--;
        }
        spin_unlock_irqrestore(&pipe->ar_usb->cs_lock, flags);

        return urb_context;
}

static void ath10k_usb_free_urb_to_pipe(struct ath10k_usb_pipe *pipe,
                                        struct ath10k_urb_context *urb_context)
{
        unsigned long flags;

        /* bail if this pipe is not initialized */
        if (!pipe->ar_usb)
                return;

        spin_lock_irqsave(&pipe->ar_usb->cs_lock, flags);

        pipe->urb_cnt++;
        list_add(&urb_context->link, &pipe->urb_list_head);

        spin_unlock_irqrestore(&pipe->ar_usb->cs_lock, flags);
}

static void ath10k_usb_cleanup_recv_urb(struct ath10k_urb_context *urb_context)
{
        dev_kfree_skb(urb_context->skb);
        urb_context->skb = NULL;

        ath10k_usb_free_urb_to_pipe(urb_context->pipe, urb_context);
}

static void ath10k_usb_free_pipe_resources(struct ath10k *ar,
                                           struct ath10k_usb_pipe *pipe)
{
        struct ath10k_urb_context *urb_context;

        if (!pipe->ar_usb) {
                /* nothing allocated for this pipe */
                return;
        }

        ath10k_dbg(ar, ATH10K_DBG_USB,
                   "usb free resources lpipe %d hpipe 0x%x urbs %d avail %d\n",
                   pipe->logical_pipe_num, pipe->usb_pipe_handle,
                   pipe->urb_alloc, pipe->urb_cnt);

        if (pipe->urb_alloc != pipe->urb_cnt) {
                ath10k_dbg(ar, ATH10K_DBG_USB,
                           "usb urb leak lpipe %d hpipe 0x%x urbs %d avail %d\n",
                           pipe->logical_pipe_num, pipe->usb_pipe_handle,
                           pipe->urb_alloc, pipe->urb_cnt);
        }

        for (;;) {
                urb_context = ath10k_usb_alloc_urb_from_pipe(pipe);

                if (!urb_context)
                        break;

                kfree(urb_context);
        }
}

static void ath10k_usb_cleanup_pipe_resources(struct ath10k *ar)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);
        int i;

        for (i = 0; i < ATH10K_USB_PIPE_MAX; i++)
                ath10k_usb_free_pipe_resources(ar, &ar_usb->pipes[i]);
}

/* hif usb rx/tx completion functions */

static void ath10k_usb_recv_complete(struct urb *urb)
{
        struct ath10k_urb_context *urb_context = urb->context;
        struct ath10k_usb_pipe *pipe = urb_context->pipe;
        struct ath10k *ar = pipe->ar_usb->ar;
        struct sk_buff *skb;
        int status = 0;

        ath10k_dbg(ar, ATH10K_DBG_USB_BULK,
                   "usb recv pipe %d stat %d len %d urb 0x%p\n",
                   pipe->logical_pipe_num, urb->status, urb->actual_length,
                   urb);

        if (urb->status != 0) {
                status = -EIO;
                switch (urb->status) {
                case -ECONNRESET:
                case -ENOENT:
                case -ESHUTDOWN:
                        /* no need to spew these errors when device
                         * removed or urb killed due to driver shutdown
                         */
                        status = -ECANCELED;
                        break;
                default:
                        ath10k_dbg(ar, ATH10K_DBG_USB_BULK,
                                   "usb recv pipe %d ep 0x%2.2x failed: %d\n",
                                   pipe->logical_pipe_num,
                                   pipe->ep_address, urb->status);
                        break;
                }
                goto cleanup_recv_urb;
        }

        if (urb->actual_length == 0)
                goto cleanup_recv_urb;

        skb = urb_context->skb;

        /* we are going to pass it up */
        urb_context->skb = NULL;
        skb_put(skb, urb->actual_length);

        /* note: queue implements a lock */
        skb_queue_tail(&pipe->io_comp_queue, skb);
        schedule_work(&pipe->io_complete_work);

cleanup_recv_urb:
        ath10k_usb_cleanup_recv_urb(urb_context);

        if (status == 0 &&
            pipe->urb_cnt >= pipe->urb_cnt_thresh) {
                /* our free urbs are piling up, post more transfers */
                ath10k_usb_post_recv_transfers(ar, pipe);
        }
}

static void ath10k_usb_transmit_complete(struct urb *urb)
{
        struct ath10k_urb_context *urb_context = urb->context;
        struct ath10k_usb_pipe *pipe = urb_context->pipe;
        struct ath10k *ar = pipe->ar_usb->ar;
        struct sk_buff *skb;

        if (urb->status != 0) {
                ath10k_dbg(ar, ATH10K_DBG_USB_BULK,
                           "pipe: %d, failed:%d\n",
                           pipe->logical_pipe_num, urb->status);
        }

        skb = urb_context->skb;
        urb_context->skb = NULL;
        ath10k_usb_free_urb_to_pipe(urb_context->pipe, urb_context);

        /* note: queue implements a lock */
        skb_queue_tail(&pipe->io_comp_queue, skb);
        schedule_work(&pipe->io_complete_work);
}

/* pipe operations */
static void ath10k_usb_post_recv_transfers(struct ath10k *ar,
                                           struct ath10k_usb_pipe *recv_pipe)
{
        struct ath10k_urb_context *urb_context;
        struct urb *urb;
        int usb_status;

        for (;;) {
                urb_context = ath10k_usb_alloc_urb_from_pipe(recv_pipe);
                if (!urb_context)
                        break;

                urb_context->skb = dev_alloc_skb(ATH10K_USB_RX_BUFFER_SIZE);
                if (!urb_context->skb)
                        goto err;

                urb = usb_alloc_urb(0, GFP_ATOMIC);
                if (!urb)
                        goto err;

                usb_fill_bulk_urb(urb,
                                  recv_pipe->ar_usb->udev,
                                  recv_pipe->usb_pipe_handle,
                                  urb_context->skb->data,
                                  ATH10K_USB_RX_BUFFER_SIZE,
                                  ath10k_usb_recv_complete, urb_context);

                ath10k_dbg(ar, ATH10K_DBG_USB_BULK,
                           "usb bulk recv submit %d 0x%x ep 0x%2.2x len %d buf 0x%p\n",
                           recv_pipe->logical_pipe_num,
                           recv_pipe->usb_pipe_handle, recv_pipe->ep_address,
                           ATH10K_USB_RX_BUFFER_SIZE, urb_context->skb);

                usb_anchor_urb(urb, &recv_pipe->urb_submitted);
                usb_status = usb_submit_urb(urb, GFP_ATOMIC);

                if (usb_status) {
                        ath10k_dbg(ar, ATH10K_DBG_USB_BULK,
                                   "usb bulk recv failed: %d\n",
                                   usb_status);
                        usb_unanchor_urb(urb);
                        usb_free_urb(urb);
                        goto err;
                }
                usb_free_urb(urb);
        }

        return;

err:
        ath10k_usb_cleanup_recv_urb(urb_context);
}

static void ath10k_usb_flush_all(struct ath10k *ar)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);
        int i;

        for (i = 0; i < ATH10K_USB_PIPE_MAX; i++) {
                if (ar_usb->pipes[i].ar_usb) {
                        usb_kill_anchored_urbs(&ar_usb->pipes[i].urb_submitted);
                        cancel_work_sync(&ar_usb->pipes[i].io_complete_work);
                }
        }
}

static void ath10k_usb_start_recv_pipes(struct ath10k *ar)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);

        ar_usb->pipes[ATH10K_USB_PIPE_RX_DATA].urb_cnt_thresh = 1;

        ath10k_usb_post_recv_transfers(ar,
                                       &ar_usb->pipes[ATH10K_USB_PIPE_RX_DATA]);
}

static void ath10k_usb_tx_complete(struct ath10k *ar, struct sk_buff *skb)
{
        struct ath10k_htc_hdr *htc_hdr;
        struct ath10k_htc_ep *ep;

        htc_hdr = (struct ath10k_htc_hdr *)skb->data;
        ep = &ar->htc.endpoint[htc_hdr->eid];
        ath10k_htc_notify_tx_completion(ep, skb);
        /* The TX complete handler now owns the skb... */
}

static void ath10k_usb_rx_complete(struct ath10k *ar, struct sk_buff *skb)
{
        struct ath10k_htc *htc = &ar->htc;
        struct ath10k_htc_hdr *htc_hdr;
        enum ath10k_htc_ep_id eid;
        struct ath10k_htc_ep *ep;
        u16 payload_len;
        u8 *trailer;
        int ret;

        htc_hdr = (struct ath10k_htc_hdr *)skb->data;
        eid = eid_from_htc_hdr(htc_hdr);
        ep = &ar->htc.endpoint[eid];

        if (ep->service_id == 0) {
                ath10k_warn(ar, "ep %d is not connected\n", eid);
                goto out_free_skb;
        }

        payload_len = le16_to_cpu(htc_hdr->len);
        if (!payload_len) {
                ath10k_warn(ar, "zero length frame received, firmware crashed?\n");
                goto out_free_skb;
        }

        if (payload_len < htc_hdr->trailer_len) {
                ath10k_warn(ar, "malformed frame received, firmware crashed?\n");
                goto out_free_skb;
        }

        if (htc_hdr->flags & ATH10K_HTC_FLAG_TRAILER_PRESENT) {
                trailer = skb->data + sizeof(*htc_hdr) + payload_len -
                          htc_hdr->trailer_len;

                ret = ath10k_htc_process_trailer(htc,
                                                 trailer,
                                                 htc_hdr->trailer_len,
                                                 eid,
                                                 NULL,
                                                 NULL);
                if (ret)
                        goto out_free_skb;

                if (is_trailer_only_msg(htc_hdr))
                        goto out_free_skb;

                /* strip off the trailer from the skb since it should not
                 * be passed on to upper layers
                 */
                skb_trim(skb, skb->len - htc_hdr->trailer_len);
        }

        skb_pull(skb, sizeof(*htc_hdr));
        ep->ep_ops.ep_rx_complete(ar, skb);
        /* The RX complete handler now owns the skb... */

        if (test_bit(ATH10K_FLAG_CORE_REGISTERED, &ar->dev_flags)) {
                local_bh_disable();
                napi_schedule(&ar->napi);
                local_bh_enable();
        }

        return;

out_free_skb:
        dev_kfree_skb(skb);
}

static void ath10k_usb_io_comp_work(struct work_struct *work)
{
        struct ath10k_usb_pipe *pipe = container_of(work,
                                                    struct ath10k_usb_pipe,
                                                    io_complete_work);
        struct ath10k *ar = pipe->ar_usb->ar;
        struct sk_buff *skb;

        while ((skb = skb_dequeue(&pipe->io_comp_queue))) {
                if (pipe->flags & ATH10K_USB_PIPE_FLAG_TX)
                        ath10k_usb_tx_complete(ar, skb);
                else
                        ath10k_usb_rx_complete(ar, skb);
        }
}

#define ATH10K_USB_MAX_DIAG_CMD (sizeof(struct ath10k_usb_ctrl_diag_cmd_write))
#define ATH10K_USB_MAX_DIAG_RESP (sizeof(struct ath10k_usb_ctrl_diag_resp_read))

static void ath10k_usb_destroy(struct ath10k *ar)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);

        ath10k_usb_flush_all(ar);
        ath10k_usb_cleanup_pipe_resources(ar);
        usb_set_intfdata(ar_usb->interface, NULL);

        kfree(ar_usb->diag_cmd_buffer);
        kfree(ar_usb->diag_resp_buffer);
}

static int ath10k_usb_hif_start(struct ath10k *ar)
{
        int i;
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);

        ath10k_core_napi_enable(ar);
        ath10k_usb_start_recv_pipes(ar);

        /* set the TX resource avail threshold for each TX pipe */
        for (i = ATH10K_USB_PIPE_TX_CTRL;
             i <= ATH10K_USB_PIPE_TX_DATA_HP; i++) {
                ar_usb->pipes[i].urb_cnt_thresh =
                    ar_usb->pipes[i].urb_alloc / 2;
        }

        return 0;
}

static int ath10k_usb_hif_tx_sg(struct ath10k *ar, u8 pipe_id,
                                struct ath10k_hif_sg_item *items, int n_items)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);
        struct ath10k_usb_pipe *pipe = &ar_usb->pipes[pipe_id];
        struct ath10k_urb_context *urb_context;
        struct sk_buff *skb;
        struct urb *urb;
        int ret, i;

        for (i = 0; i < n_items; i++) {
                urb_context = ath10k_usb_alloc_urb_from_pipe(pipe);
                if (!urb_context) {
                        ret = -ENOMEM;
                        goto err;
                }

                skb = items[i].transfer_context;
                urb_context->skb = skb;

                urb = usb_alloc_urb(0, GFP_ATOMIC);
                if (!urb) {
                        ret = -ENOMEM;
                        goto err_free_urb_to_pipe;
                }

                usb_fill_bulk_urb(urb,
                                  ar_usb->udev,
                                  pipe->usb_pipe_handle,
                                  skb->data,
                                  skb->len,
                                  ath10k_usb_transmit_complete, urb_context);

                if (!(skb->len % pipe->max_packet_size)) {
                        /* hit a max packet boundary on this pipe */
                        urb->transfer_flags |= URB_ZERO_PACKET;
                }

                usb_anchor_urb(urb, &pipe->urb_submitted);
                ret = usb_submit_urb(urb, GFP_ATOMIC);
                if (ret) {
                        ath10k_dbg(ar, ATH10K_DBG_USB_BULK,
                                   "usb bulk transmit failed: %d\n", ret);
                        usb_unanchor_urb(urb);
                        usb_free_urb(urb);
                        ret = -EINVAL;
                        goto err_free_urb_to_pipe;
                }

                usb_free_urb(urb);
        }

        return 0;

err_free_urb_to_pipe:
        ath10k_usb_free_urb_to_pipe(urb_context->pipe, urb_context);
err:
        return ret;
}

static void ath10k_usb_hif_stop(struct ath10k *ar)
{
        ath10k_usb_flush_all(ar);
        ath10k_core_napi_sync_disable(ar);
}

static u16 ath10k_usb_hif_get_free_queue_number(struct ath10k *ar, u8 pipe_id)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);

        return ar_usb->pipes[pipe_id].urb_cnt;
}

static int ath10k_usb_submit_ctrl_out(struct ath10k *ar,
                                      u8 req, u16 value, u16 index, void *data,
                                      u32 size)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);
        u8 *buf = NULL;
        int ret;

        if (size > 0) {
                buf = kmemdup(data, size, GFP_KERNEL);
                if (!buf)
                        return -ENOMEM;
        }

        /* note: if successful returns number of bytes transferred */
        ret = usb_control_msg(ar_usb->udev,
                              usb_sndctrlpipe(ar_usb->udev, 0),
                              req,
                              USB_DIR_OUT | USB_TYPE_VENDOR |
                              USB_RECIP_DEVICE, value, index, buf,
                              size, 1000);

        if (ret < 0) {
                ath10k_warn(ar, "Failed to submit usb control message: %d\n",
                            ret);
                kfree(buf);
                return ret;
        }

        kfree(buf);

        return 0;
}

static int ath10k_usb_submit_ctrl_in(struct ath10k *ar,
                                     u8 req, u16 value, u16 index, void *data,
                                     u32 size)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);
        u8 *buf = NULL;
        int ret;

        if (size > 0) {
                buf = kmalloc(size, GFP_KERNEL);
                if (!buf)
                        return -ENOMEM;
        }

        /* note: if successful returns number of bytes transferred */
        ret = usb_control_msg(ar_usb->udev,
                              usb_rcvctrlpipe(ar_usb->udev, 0),
                              req,
                              USB_DIR_IN | USB_TYPE_VENDOR |
                              USB_RECIP_DEVICE, value, index, buf,
                              size, 2000);

        if (ret < 0) {
                ath10k_warn(ar, "Failed to read usb control message: %d\n",
                            ret);
                kfree(buf);
                return ret;
        }

        memcpy((u8 *)data, buf, size);

        kfree(buf);

        return 0;
}

static int ath10k_usb_ctrl_msg_exchange(struct ath10k *ar,
                                        u8 req_val, u8 *req_buf, u32 req_len,
                                        u8 resp_val, u8 *resp_buf,
                                        u32 *resp_len)
{
        int ret;

        /* send command */
        ret = ath10k_usb_submit_ctrl_out(ar, req_val, 0, 0,
                                         req_buf, req_len);
        if (ret)
                goto err;

        /* get response */
        if (resp_buf) {
                ret = ath10k_usb_submit_ctrl_in(ar, resp_val, 0, 0,
                                                resp_buf, *resp_len);
                if (ret)
                        goto err;
        }

        return 0;
err:
        return ret;
}

static int ath10k_usb_hif_diag_read(struct ath10k *ar, u32 address, void *buf,
                                    size_t buf_len)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);
        struct ath10k_usb_ctrl_diag_cmd_read *cmd;
        u32 resp_len;
        int ret;

        if (buf_len < sizeof(struct ath10k_usb_ctrl_diag_resp_read))
                return -EINVAL;

        cmd = (struct ath10k_usb_ctrl_diag_cmd_read *)ar_usb->diag_cmd_buffer;
        memset(cmd, 0, sizeof(*cmd));
        cmd->cmd = ATH10K_USB_CTRL_DIAG_CC_READ;
        cmd->address = cpu_to_le32(address);
        resp_len = sizeof(struct ath10k_usb_ctrl_diag_resp_read);

        ret = ath10k_usb_ctrl_msg_exchange(ar,
                                           ATH10K_USB_CONTROL_REQ_DIAG_CMD,
                                           (u8 *)cmd,
                                           sizeof(*cmd),
                                           ATH10K_USB_CONTROL_REQ_DIAG_RESP,
                                           ar_usb->diag_resp_buffer, &resp_len);
        if (ret)
                return ret;

        if (resp_len != sizeof(struct ath10k_usb_ctrl_diag_resp_read))
                return -EMSGSIZE;

        memcpy(buf, ar_usb->diag_resp_buffer,
               sizeof(struct ath10k_usb_ctrl_diag_resp_read));

        return 0;
}

static int ath10k_usb_hif_diag_write(struct ath10k *ar, u32 address,
                                     const void *data, int nbytes)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);
        struct ath10k_usb_ctrl_diag_cmd_write *cmd;
        int ret;

        if (nbytes != sizeof(cmd->value))
                return -EINVAL;

        cmd = (struct ath10k_usb_ctrl_diag_cmd_write *)ar_usb->diag_cmd_buffer;
        memset(cmd, 0, sizeof(*cmd));
        cmd->cmd = cpu_to_le32(ATH10K_USB_CTRL_DIAG_CC_WRITE);
        cmd->address = cpu_to_le32(address);
        memcpy(&cmd->value, data, nbytes);

        ret = ath10k_usb_ctrl_msg_exchange(ar,
                                           ATH10K_USB_CONTROL_REQ_DIAG_CMD,
                                           (u8 *)cmd,
                                           sizeof(*cmd),
                                           0, NULL, NULL);
        if (ret)
                return ret;

        return 0;
}

static int ath10k_usb_bmi_exchange_msg(struct ath10k *ar,
                                       void *req, u32 req_len,
                                       void *resp, u32 *resp_len)
{
        int ret;

        if (req) {
                ret = ath10k_usb_submit_ctrl_out(ar,
                                                 ATH10K_USB_CONTROL_REQ_SEND_BMI_CMD,
                                                 0, 0, req, req_len);
                if (ret) {
                        ath10k_warn(ar,
                                    "unable to send the bmi data to the device: %d\n",
                                    ret);
                        return ret;
                }
        }

        if (resp) {
                ret = ath10k_usb_submit_ctrl_in(ar,
                                                ATH10K_USB_CONTROL_REQ_RECV_BMI_RESP,
                                                0, 0, resp, *resp_len);
                if (ret) {
                        ath10k_warn(ar,
                                    "Unable to read the bmi data from the device: %d\n",
                                    ret);
                        return ret;
                }
        }

        return 0;
}

static void ath10k_usb_hif_get_default_pipe(struct ath10k *ar,
                                            u8 *ul_pipe, u8 *dl_pipe)
{
        *ul_pipe = ATH10K_USB_PIPE_TX_CTRL;
        *dl_pipe = ATH10K_USB_PIPE_RX_CTRL;
}

static int ath10k_usb_hif_map_service_to_pipe(struct ath10k *ar, u16 svc_id,
                                              u8 *ul_pipe, u8 *dl_pipe)
{
        switch (svc_id) {
        case ATH10K_HTC_SVC_ID_RSVD_CTRL:
        case ATH10K_HTC_SVC_ID_WMI_CONTROL:
                *ul_pipe = ATH10K_USB_PIPE_TX_CTRL;
                /* due to large control packets, shift to data pipe */
                *dl_pipe = ATH10K_USB_PIPE_RX_DATA;
                break;
        case ATH10K_HTC_SVC_ID_HTT_DATA_MSG:
                *ul_pipe = ATH10K_USB_PIPE_TX_DATA_LP;
                /* Disable rxdata2 directly, it will be enabled
                 * if FW enable rxdata2
                 */
                *dl_pipe = ATH10K_USB_PIPE_RX_DATA;
                break;
        default:
                return -EPERM;
        }

        return 0;
}

static int ath10k_usb_hif_power_up(struct ath10k *ar,
                                   enum ath10k_firmware_mode fw_mode)
{
        return 0;
}

static void ath10k_usb_hif_power_down(struct ath10k *ar)
{
        ath10k_usb_flush_all(ar);
}

#ifdef CONFIG_PM

static int ath10k_usb_hif_suspend(struct ath10k *ar)
{
        return -EOPNOTSUPP;
}

static int ath10k_usb_hif_resume(struct ath10k *ar)
{
        return -EOPNOTSUPP;
}
#endif

static const struct ath10k_hif_ops ath10k_usb_hif_ops = {
        .tx_sg                  = ath10k_usb_hif_tx_sg,
        .diag_read              = ath10k_usb_hif_diag_read,
        .diag_write             = ath10k_usb_hif_diag_write,
        .exchange_bmi_msg       = ath10k_usb_bmi_exchange_msg,
        .start                  = ath10k_usb_hif_start,
        .stop                   = ath10k_usb_hif_stop,
        .map_service_to_pipe    = ath10k_usb_hif_map_service_to_pipe,
        .get_default_pipe       = ath10k_usb_hif_get_default_pipe,
        .get_free_queue_number  = ath10k_usb_hif_get_free_queue_number,
        .power_up               = ath10k_usb_hif_power_up,
        .power_down             = ath10k_usb_hif_power_down,
#ifdef CONFIG_PM
        .suspend                = ath10k_usb_hif_suspend,
        .resume                 = ath10k_usb_hif_resume,
#endif
};

static u8 ath10k_usb_get_logical_pipe_num(u8 ep_address, int *urb_count)
{
        u8 pipe_num = ATH10K_USB_PIPE_INVALID;

        switch (ep_address) {
        case ATH10K_USB_EP_ADDR_APP_CTRL_IN:
                pipe_num = ATH10K_USB_PIPE_RX_CTRL;
                *urb_count = RX_URB_COUNT;
                break;
        case ATH10K_USB_EP_ADDR_APP_DATA_IN:
                pipe_num = ATH10K_USB_PIPE_RX_DATA;
                *urb_count = RX_URB_COUNT;
                break;
        case ATH10K_USB_EP_ADDR_APP_INT_IN:
                pipe_num = ATH10K_USB_PIPE_RX_INT;
                *urb_count = RX_URB_COUNT;
                break;
        case ATH10K_USB_EP_ADDR_APP_DATA2_IN:
                pipe_num = ATH10K_USB_PIPE_RX_DATA2;
                *urb_count = RX_URB_COUNT;
                break;
        case ATH10K_USB_EP_ADDR_APP_CTRL_OUT:
                pipe_num = ATH10K_USB_PIPE_TX_CTRL;
                *urb_count = TX_URB_COUNT;
                break;
        case ATH10K_USB_EP_ADDR_APP_DATA_LP_OUT:
                pipe_num = ATH10K_USB_PIPE_TX_DATA_LP;
                *urb_count = TX_URB_COUNT;
                break;
        case ATH10K_USB_EP_ADDR_APP_DATA_MP_OUT:
                pipe_num = ATH10K_USB_PIPE_TX_DATA_MP;
                *urb_count = TX_URB_COUNT;
                break;
        case ATH10K_USB_EP_ADDR_APP_DATA_HP_OUT:
                pipe_num = ATH10K_USB_PIPE_TX_DATA_HP;
                *urb_count = TX_URB_COUNT;
                break;
        default:
                /* note: there may be endpoints not currently used */
                break;
        }

        return pipe_num;
}

static int ath10k_usb_alloc_pipe_resources(struct ath10k *ar,
                                           struct ath10k_usb_pipe *pipe,
                                           int urb_cnt)
{
        struct ath10k_urb_context *urb_context;
        int i;

        INIT_LIST_HEAD(&pipe->urb_list_head);
        init_usb_anchor(&pipe->urb_submitted);

        for (i = 0; i < urb_cnt; i++) {
                urb_context = kzalloc_obj(*urb_context);
                if (!urb_context)
                        return -ENOMEM;

                urb_context->pipe = pipe;

                /* we are only allocate the urb contexts here, the actual URB
                 * is allocated from the kernel as needed to do a transaction
                 */
                pipe->urb_alloc++;
                ath10k_usb_free_urb_to_pipe(pipe, urb_context);
        }

        ath10k_dbg(ar, ATH10K_DBG_USB,
                   "usb alloc resources lpipe %d hpipe 0x%x urbs %d\n",
                   pipe->logical_pipe_num, pipe->usb_pipe_handle,
                   pipe->urb_alloc);

        return 0;
}

static int ath10k_usb_setup_pipe_resources(struct ath10k *ar,
                                           struct usb_interface *interface)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);
        struct usb_host_interface *iface_desc = interface->cur_altsetting;
        struct usb_endpoint_descriptor *endpoint;
        struct ath10k_usb_pipe *pipe;
        int ret, i, urbcount;
        u8 pipe_num;

        ath10k_dbg(ar, ATH10K_DBG_USB, "usb setting up pipes using interface\n");

        /* walk descriptors and setup pipes */
        for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
                endpoint = &iface_desc->endpoint[i].desc;

                if (ATH10K_USB_IS_BULK_EP(endpoint->bmAttributes)) {
                        ath10k_dbg(ar, ATH10K_DBG_USB,
                                   "usb %s bulk ep 0x%2.2x maxpktsz %d\n",
                                   ATH10K_USB_IS_DIR_IN
                                   (endpoint->bEndpointAddress) ?
                                   "rx" : "tx", endpoint->bEndpointAddress,
                                   le16_to_cpu(endpoint->wMaxPacketSize));
                } else if (ATH10K_USB_IS_INT_EP(endpoint->bmAttributes)) {
                        ath10k_dbg(ar, ATH10K_DBG_USB,
                                   "usb %s int ep 0x%2.2x maxpktsz %d interval %d\n",
                                   ATH10K_USB_IS_DIR_IN
                                   (endpoint->bEndpointAddress) ?
                                   "rx" : "tx", endpoint->bEndpointAddress,
                                   le16_to_cpu(endpoint->wMaxPacketSize),
                                   endpoint->bInterval);
                } else if (ATH10K_USB_IS_ISOC_EP(endpoint->bmAttributes)) {
                        /* TODO for ISO */
                        ath10k_dbg(ar, ATH10K_DBG_USB,
                                   "usb %s isoc ep 0x%2.2x maxpktsz %d interval %d\n",
                                   ATH10K_USB_IS_DIR_IN
                                   (endpoint->bEndpointAddress) ?
                                   "rx" : "tx", endpoint->bEndpointAddress,
                                   le16_to_cpu(endpoint->wMaxPacketSize),
                                   endpoint->bInterval);
                }

                /* Ignore broken descriptors. */
                if (usb_endpoint_maxp(endpoint) == 0)
                        continue;

                urbcount = 0;

                pipe_num =
                    ath10k_usb_get_logical_pipe_num(endpoint->bEndpointAddress,
                                                    &urbcount);
                if (pipe_num == ATH10K_USB_PIPE_INVALID)
                        continue;

                pipe = &ar_usb->pipes[pipe_num];
                if (pipe->ar_usb)
                        /* hmmm..pipe was already setup */
                        continue;

                pipe->ar_usb = ar_usb;
                pipe->logical_pipe_num = pipe_num;
                pipe->ep_address = endpoint->bEndpointAddress;
                pipe->max_packet_size = le16_to_cpu(endpoint->wMaxPacketSize);

                if (ATH10K_USB_IS_BULK_EP(endpoint->bmAttributes)) {
                        if (ATH10K_USB_IS_DIR_IN(pipe->ep_address)) {
                                pipe->usb_pipe_handle =
                                    usb_rcvbulkpipe(ar_usb->udev,
                                                    pipe->ep_address);
                        } else {
                                pipe->usb_pipe_handle =
                                    usb_sndbulkpipe(ar_usb->udev,
                                                    pipe->ep_address);
                        }
                } else if (ATH10K_USB_IS_INT_EP(endpoint->bmAttributes)) {
                        if (ATH10K_USB_IS_DIR_IN(pipe->ep_address)) {
                                pipe->usb_pipe_handle =
                                    usb_rcvintpipe(ar_usb->udev,
                                                   pipe->ep_address);
                        } else {
                                pipe->usb_pipe_handle =
                                    usb_sndintpipe(ar_usb->udev,
                                                   pipe->ep_address);
                        }
                } else if (ATH10K_USB_IS_ISOC_EP(endpoint->bmAttributes)) {
                        /* TODO for ISO */
                        if (ATH10K_USB_IS_DIR_IN(pipe->ep_address)) {
                                pipe->usb_pipe_handle =
                                    usb_rcvisocpipe(ar_usb->udev,
                                                    pipe->ep_address);
                        } else {
                                pipe->usb_pipe_handle =
                                    usb_sndisocpipe(ar_usb->udev,
                                                    pipe->ep_address);
                        }
                }

                pipe->ep_desc = endpoint;

                if (!ATH10K_USB_IS_DIR_IN(pipe->ep_address))
                        pipe->flags |= ATH10K_USB_PIPE_FLAG_TX;

                ret = ath10k_usb_alloc_pipe_resources(ar, pipe, urbcount);
                if (ret)
                        return ret;
        }

        return 0;
}

static int ath10k_usb_create(struct ath10k *ar,
                             struct usb_interface *interface)
{
        struct ath10k_usb *ar_usb = ath10k_usb_priv(ar);
        struct usb_device *dev = interface_to_usbdev(interface);
        struct ath10k_usb_pipe *pipe;
        int ret, i;

        usb_set_intfdata(interface, ar_usb);
        spin_lock_init(&ar_usb->cs_lock);
        ar_usb->udev = dev;
        ar_usb->interface = interface;

        for (i = 0; i < ATH10K_USB_PIPE_MAX; i++) {
                pipe = &ar_usb->pipes[i];
                INIT_WORK(&pipe->io_complete_work,
                          ath10k_usb_io_comp_work);
                skb_queue_head_init(&pipe->io_comp_queue);
        }

        ar_usb->diag_cmd_buffer = kzalloc(ATH10K_USB_MAX_DIAG_CMD, GFP_KERNEL);
        if (!ar_usb->diag_cmd_buffer) {
                ret = -ENOMEM;
                goto err;
        }

        ar_usb->diag_resp_buffer = kzalloc(ATH10K_USB_MAX_DIAG_RESP,
                                           GFP_KERNEL);
        if (!ar_usb->diag_resp_buffer) {
                ret = -ENOMEM;
                goto err;
        }

        ret = ath10k_usb_setup_pipe_resources(ar, interface);
        if (ret)
                goto err;

        return 0;

err:
        ath10k_usb_destroy(ar);
        return ret;
}

static int ath10k_usb_napi_poll(struct napi_struct *ctx, int budget)
{
        struct ath10k *ar = container_of(ctx, struct ath10k, napi);
        int done;

        done = ath10k_htt_rx_hl_indication(ar, budget);
        ath10k_dbg(ar, ATH10K_DBG_USB, "napi poll: done: %d, budget:%d\n", done, budget);

        if (done < budget)
                napi_complete_done(ctx, done);

        return done;
}

/* ath10k usb driver registered functions */
static int ath10k_usb_probe(struct usb_interface *interface,
                            const struct usb_device_id *id)
{
        struct ath10k *ar;
        struct ath10k_usb *ar_usb;
        struct usb_device *dev = interface_to_usbdev(interface);
        int ret, vendor_id, product_id;
        enum ath10k_hw_rev hw_rev;
        struct ath10k_bus_params bus_params = {};

        /* Assumption: All USB based chipsets (so far) are QCA9377 based.
         * If there will be newer chipsets that does not use the hw reg
         * setup as defined in qca6174_regs and qca6174_values, this
         * assumption is no longer valid and hw_rev must be setup differently
         * depending on chipset.
         */
        hw_rev = ATH10K_HW_QCA9377;

        ar = ath10k_core_create(sizeof(*ar_usb), &dev->dev, ATH10K_BUS_USB,
                                hw_rev, &ath10k_usb_hif_ops);
        if (!ar) {
                dev_err(&dev->dev, "failed to allocate core\n");
                return -ENOMEM;
        }

        netif_napi_add(ar->napi_dev, &ar->napi, ath10k_usb_napi_poll);

        usb_get_dev(dev);
        vendor_id = le16_to_cpu(dev->descriptor.idVendor);
        product_id = le16_to_cpu(dev->descriptor.idProduct);

        ath10k_dbg(ar, ATH10K_DBG_BOOT,
                   "usb new func vendor 0x%04x product 0x%04x\n",
                   vendor_id, product_id);

        ar_usb = ath10k_usb_priv(ar);
        ret = ath10k_usb_create(ar, interface);
        if (ret)
                goto err;
        ar_usb->ar = ar;

        ar->dev_id = product_id;
        ar->id.vendor = vendor_id;
        ar->id.device = product_id;

        bus_params.dev_type = ATH10K_DEV_TYPE_HL;
        /* TODO: don't know yet how to get chip_id with USB */
        bus_params.chip_id = 0;
        bus_params.hl_msdu_ids = true;
        ret = ath10k_core_register(ar, &bus_params);
        if (ret) {
                ath10k_warn(ar, "failed to register driver core: %d\n", ret);
                goto err_usb_destroy;
        }

        /* TODO: remove this once USB support is fully implemented */
        ath10k_warn(ar, "Warning: ath10k USB support is incomplete, don't expect anything to work!\n");

        return 0;

err_usb_destroy:
        ath10k_usb_destroy(ar);

err:
        ath10k_core_destroy(ar);

        usb_put_dev(dev);

        return ret;
}

static void ath10k_usb_remove(struct usb_interface *interface)
{
        struct ath10k_usb *ar_usb;

        ar_usb = usb_get_intfdata(interface);
        if (!ar_usb)
                return;

        ath10k_core_unregister(ar_usb->ar);
        netif_napi_del(&ar_usb->ar->napi);
        ath10k_usb_destroy(ar_usb->ar);
        usb_put_dev(interface_to_usbdev(interface));
        ath10k_core_destroy(ar_usb->ar);
}

#ifdef CONFIG_PM

static int ath10k_usb_pm_suspend(struct usb_interface *interface,
                                 pm_message_t message)
{
        struct ath10k_usb *ar_usb = usb_get_intfdata(interface);

        ath10k_usb_flush_all(ar_usb->ar);
        return 0;
}

static int ath10k_usb_pm_resume(struct usb_interface *interface)
{
        struct ath10k_usb *ar_usb = usb_get_intfdata(interface);
        struct ath10k *ar = ar_usb->ar;

        ath10k_usb_post_recv_transfers(ar,
                                       &ar_usb->pipes[ATH10K_USB_PIPE_RX_DATA]);

        return 0;
}

#else

#define ath10k_usb_pm_suspend NULL
#define ath10k_usb_pm_resume NULL

#endif

/* table of devices that work with this driver */
static struct usb_device_id ath10k_usb_ids[] = {
        {USB_DEVICE(0x13b1, 0x0042)}, /* Linksys WUSB6100M */
        { /* Terminating entry */ },
};

MODULE_DEVICE_TABLE(usb, ath10k_usb_ids);

static struct usb_driver ath10k_usb_driver = {
        .name = "ath10k_usb",
        .probe = ath10k_usb_probe,
        .suspend = ath10k_usb_pm_suspend,
        .resume = ath10k_usb_pm_resume,
        .disconnect = ath10k_usb_remove,
        .id_table = ath10k_usb_ids,
        .supports_autosuspend = true,
        .disable_hub_initiated_lpm = 1,
};

module_usb_driver(ath10k_usb_driver);

MODULE_AUTHOR("Atheros Communications, Inc.");
MODULE_DESCRIPTION("Driver support for Qualcomm Atheros USB 802.11ac WLAN devices");
MODULE_LICENSE("Dual BSD/GPL");