htc_hst.c

Go to the documentation of this file.

/*
 * Copyright (c) 2010-2011 Atheros Communications Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include "htc.h"

static int htc_issue_send(struct htc_target *target, struct sk_buff* skb,
              u16 len, u8 flags, u8 epid)

{
    struct htc_frame_hdr *hdr;
    struct htc_endpoint *endpoint = &target->endpoint[epid];
    int status;

    hdr = (struct htc_frame_hdr *)
        skb_push(skb, sizeof(struct htc_frame_hdr));
    hdr->endpoint_id = epid;
    hdr->flags = flags;
    hdr->payload_len = cpu_to_be16(len);

    status = target->hif->send(target->hif_dev, endpoint->ul_pipeid, skb);

    return status;
}

static struct htc_endpoint *get_next_avail_ep(struct htc_endpoint *endpoint)
{
    enum htc_endpoint_id avail_epid;

    for (avail_epid = (ENDPOINT_MAX - 1); avail_epid > ENDPOINT0; avail_epid--)
        if (endpoint[avail_epid].service_id == 0)
            return &endpoint[avail_epid];
    return NULL;
}

static u8 service_to_ulpipe(u16 service_id)
{
    switch (service_id) {
    case WMI_CONTROL_SVC:
        return 4;
    case WMI_BEACON_SVC:
    case WMI_CAB_SVC:
    case WMI_UAPSD_SVC:
    case WMI_MGMT_SVC:
    case WMI_DATA_VO_SVC:
    case WMI_DATA_VI_SVC:
    case WMI_DATA_BE_SVC:
    case WMI_DATA_BK_SVC:
        return 1;
    default:
        return 0;
    }
}

static u8 service_to_dlpipe(u16 service_id)
{
    switch (service_id) {
    case WMI_CONTROL_SVC:
        return 3;
    case WMI_BEACON_SVC:
    case WMI_CAB_SVC:
    case WMI_UAPSD_SVC:
    case WMI_MGMT_SVC:
    case WMI_DATA_VO_SVC:
    case WMI_DATA_VI_SVC:
    case WMI_DATA_BE_SVC:
    case WMI_DATA_BK_SVC:
        return 2;
    default:
        return 0;
    }
}

static void htc_process_target_rdy(struct htc_target *target,
                   void *buf)
{
    struct htc_endpoint *endpoint;
    struct htc_ready_msg *htc_ready_msg = (struct htc_ready_msg *) buf;

    target->credit_size = be16_to_cpu(htc_ready_msg->credit_size);

    endpoint = &target->endpoint[ENDPOINT0];
    endpoint->service_id = HTC_CTRL_RSVD_SVC;
    endpoint->max_msglen = HTC_MAX_CONTROL_MESSAGE_LENGTH;
    atomic_inc(&target->tgt_ready);
    complete(&target->target_wait);
}

static void htc_process_conn_rsp(struct htc_target *target,
                 struct htc_frame_hdr *htc_hdr)
{
    struct htc_conn_svc_rspmsg *svc_rspmsg;
    struct htc_endpoint *endpoint, *tmp_endpoint = NULL;
    u16 service_id;
    u16 max_msglen;
    enum htc_endpoint_id epid, tepid;

    svc_rspmsg = (struct htc_conn_svc_rspmsg *)
        ((void *) htc_hdr + sizeof(struct htc_frame_hdr));

    if (svc_rspmsg->status == HTC_SERVICE_SUCCESS) {
        epid = svc_rspmsg->endpoint_id;
        service_id = be16_to_cpu(svc_rspmsg->service_id);
        max_msglen = be16_to_cpu(svc_rspmsg->max_msg_len);
        endpoint = &target->endpoint[epid];

        for (tepid = (ENDPOINT_MAX - 1); tepid > ENDPOINT0; tepid--) {
            tmp_endpoint = &target->endpoint[tepid];
            if (tmp_endpoint->service_id == service_id) {
                tmp_endpoint->service_id = 0;
                break;
            }
        }

        if (tepid == ENDPOINT0)
            return;

        endpoint->service_id = service_id;
        endpoint->max_txqdepth = tmp_endpoint->max_txqdepth;
        endpoint->ep_callbacks = tmp_endpoint->ep_callbacks;
        endpoint->ul_pipeid = tmp_endpoint->ul_pipeid;
        endpoint->dl_pipeid = tmp_endpoint->dl_pipeid;
        endpoint->max_msglen = max_msglen;
        target->conn_rsp_epid = epid;
        complete(&target->cmd_wait);
    } else {
        target->conn_rsp_epid = ENDPOINT_UNUSED;
    }
}

static int htc_config_pipe_credits(struct htc_target *target)
{
    struct sk_buff *skb;
    struct htc_config_pipe_msg *cp_msg;
    int ret, time_left;

    skb = alloc_skb(50 + sizeof(struct htc_frame_hdr), GFP_ATOMIC);
    if (!skb) {
        dev_err(target->dev, "failed to allocate send buffer\n");
        return -ENOMEM;
    }
    skb_reserve(skb, sizeof(struct htc_frame_hdr));

    cp_msg = (struct htc_config_pipe_msg *)
        skb_put(skb, sizeof(struct htc_config_pipe_msg));

    cp_msg->message_id = cpu_to_be16(HTC_MSG_CONFIG_PIPE_ID);
    cp_msg->pipe_id = USB_WLAN_TX_PIPE;
    cp_msg->credits = target->credits;

    target->htc_flags |= HTC_OP_CONFIG_PIPE_CREDITS;

    ret = htc_issue_send(target, skb, skb->len, 0, ENDPOINT0);
    if (ret)
        goto err;

    time_left = wait_for_completion_timeout(&target->cmd_wait, HZ);
    if (!time_left) {
        dev_err(target->dev, "HTC credit config timeout\n");
        return -ETIMEDOUT;
    }

    return 0;
err:
    kfree_skb(skb);
    return -EINVAL;
}

static int htc_setup_complete(struct htc_target *target)
{
    struct sk_buff *skb;
    struct htc_comp_msg *comp_msg;
    int ret = 0, time_left;

    skb = alloc_skb(50 + sizeof(struct htc_frame_hdr), GFP_ATOMIC);
    if (!skb) {
        dev_err(target->dev, "failed to allocate send buffer\n");
        return -ENOMEM;
    }
    skb_reserve(skb, sizeof(struct htc_frame_hdr));

    comp_msg = (struct htc_comp_msg *)
        skb_put(skb, sizeof(struct htc_comp_msg));
    comp_msg->msg_id = cpu_to_be16(HTC_MSG_SETUP_COMPLETE_ID);

    target->htc_flags |= HTC_OP_START_WAIT;

    ret = htc_issue_send(target, skb, skb->len, 0, ENDPOINT0);
    if (ret)
        goto err;

    time_left = wait_for_completion_timeout(&target->cmd_wait, HZ);
    if (!time_left) {
        dev_err(target->dev, "HTC start timeout\n");
        return -ETIMEDOUT;
    }

    return 0;

err:
    kfree_skb(skb);
    return -EINVAL;
}

/* HTC APIs */

int htc_init(struct htc_target *target)
{
    int ret;

    ret = htc_config_pipe_credits(target);
    if (ret)
        return ret;

    return htc_setup_complete(target);
}

int htc_connect_service(struct htc_target *target,
             struct htc_service_connreq *service_connreq,
             enum htc_endpoint_id *conn_rsp_epid)
{
    struct sk_buff *skb;
    struct htc_endpoint *endpoint;
    struct htc_conn_svc_msg *conn_msg;
    int ret, time_left;

    /* Find an available endpoint */
    endpoint = get_next_avail_ep(target->endpoint);
    if (!endpoint) {
        dev_err(target->dev, "Endpoint is not available for"
            "service %d\n", service_connreq->service_id);
        return -EINVAL;
    }

    endpoint->service_id = service_connreq->service_id;
    endpoint->max_txqdepth = service_connreq->max_send_qdepth;
    endpoint->ul_pipeid = service_to_ulpipe(service_connreq->service_id);
    endpoint->dl_pipeid = service_to_dlpipe(service_connreq->service_id);
    endpoint->ep_callbacks = service_connreq->ep_callbacks;

    skb = alloc_skb(sizeof(struct htc_conn_svc_msg) +
                sizeof(struct htc_frame_hdr), GFP_ATOMIC);
    if (!skb) {
        dev_err(target->dev, "Failed to allocate buf to send"
            "service connect req\n");
        return -ENOMEM;
    }

    skb_reserve(skb, sizeof(struct htc_frame_hdr));

    conn_msg = (struct htc_conn_svc_msg *)
            skb_put(skb, sizeof(struct htc_conn_svc_msg));
    conn_msg->service_id = cpu_to_be16(service_connreq->service_id);
    conn_msg->msg_id = cpu_to_be16(HTC_MSG_CONNECT_SERVICE_ID);
    conn_msg->con_flags = cpu_to_be16(service_connreq->con_flags);
    conn_msg->dl_pipeid = endpoint->dl_pipeid;
    conn_msg->ul_pipeid = endpoint->ul_pipeid;

    ret = htc_issue_send(target, skb, skb->len, 0, ENDPOINT0);
    if (ret)
        goto err;

    time_left = wait_for_completion_timeout(&target->cmd_wait, HZ);
    if (!time_left) {
        dev_err(target->dev, "Service connection timeout for: %d\n",
            service_connreq->service_id);
        return -ETIMEDOUT;
    }

    *conn_rsp_epid = target->conn_rsp_epid;
    return 0;
err:
    kfree_skb(skb);
    return ret;
}

int htc_send(struct htc_target *target, struct sk_buff *skb)
{
    struct ath9k_htc_tx_ctl *tx_ctl;

    tx_ctl = HTC_SKB_CB(skb);
    return htc_issue_send(target, skb, skb->len, 0, tx_ctl->epid);
}

int htc_send_epid(struct htc_target *target, struct sk_buff *skb,
          enum htc_endpoint_id epid)
{
    return htc_issue_send(target, skb, skb->len, 0, epid);
}

void htc_stop(struct htc_target *target)
{
    target->hif->stop(target->hif_dev);
}

void htc_start(struct htc_target *target)
{
    target->hif->start(target->hif_dev);
}

void htc_sta_drain(struct htc_target *target, u8 idx)
{
    target->hif->sta_drain(target->hif_dev, idx);
}

void ath9k_htc_txcompletion_cb(struct htc_target *htc_handle,
                   struct sk_buff *skb, bool txok)
{
    struct htc_endpoint *endpoint;
    struct htc_frame_hdr *htc_hdr = NULL;

    if (htc_handle->htc_flags & HTC_OP_CONFIG_PIPE_CREDITS) {
        complete(&htc_handle->cmd_wait);
        htc_handle->htc_flags &= ~HTC_OP_CONFIG_PIPE_CREDITS;
        goto ret;
    }

    if (htc_handle->htc_flags & HTC_OP_START_WAIT) {
        complete(&htc_handle->cmd_wait);
        htc_handle->htc_flags &= ~HTC_OP_START_WAIT;
        goto ret;
    }

    if (skb) {
        htc_hdr = (struct htc_frame_hdr *) skb->data;
        endpoint = &htc_handle->endpoint[htc_hdr->endpoint_id];
        skb_pull(skb, sizeof(struct htc_frame_hdr));

        if (endpoint->ep_callbacks.tx) {
            endpoint->ep_callbacks.tx(endpoint->ep_callbacks.priv,
                          skb, htc_hdr->endpoint_id,
                          txok);
        }
    }

    return;
ret:
    /* HTC-generated packets are freed here. */
    if (htc_hdr && htc_hdr->endpoint_id != ENDPOINT0)
        dev_kfree_skb_any(skb);
    else
        kfree_skb(skb);
}

/*
 * HTC Messages are handled directly here and the obtained SKB
 * is freed.
 *
 * Service messages (Data, WMI) passed to the corresponding
 * endpoint RX handlers, which have to free the SKB.
 */
void ath9k_htc_rx_msg(struct htc_target *htc_handle,
              struct sk_buff *skb, u32 len, u8 pipe_id)
{
    struct htc_frame_hdr *htc_hdr;
    enum htc_endpoint_id epid;
    struct htc_endpoint *endpoint;
    __be16 *msg_id;

    if (!htc_handle || !skb)
        return;

    htc_hdr = (struct htc_frame_hdr *) skb->data;
    epid = htc_hdr->endpoint_id;

    if (epid >= ENDPOINT_MAX) {
        if (pipe_id != USB_REG_IN_PIPE)
            dev_kfree_skb_any(skb);
        else
            kfree_skb(skb);
        return;
    }

    if (epid == ENDPOINT0) {

        /* Handle trailer */
        if (htc_hdr->flags & HTC_FLAGS_RECV_TRAILER) {
            if (be32_to_cpu(*(__be32 *) skb->data) == 0x00C60000)
                /* Move past the Watchdog pattern */
                htc_hdr = (struct htc_frame_hdr *)(skb->data + 4);
        }

        /* Get the message ID */
        msg_id = (__be16 *) ((void *) htc_hdr +
                     sizeof(struct htc_frame_hdr));

        /* Now process HTC messages */
        switch (be16_to_cpu(*msg_id)) {
        case HTC_MSG_READY_ID:
            htc_process_target_rdy(htc_handle, htc_hdr);
            break;
        case HTC_MSG_CONNECT_SERVICE_RESPONSE_ID:
            htc_process_conn_rsp(htc_handle, htc_hdr);
            break;
        default:
            break;
        }

        kfree_skb(skb);

    } else {
        if (htc_hdr->flags & HTC_FLAGS_RECV_TRAILER)
            skb_trim(skb, len - htc_hdr->control[0]);

        skb_pull(skb, sizeof(struct htc_frame_hdr));

        endpoint = &htc_handle->endpoint[epid];
        if (endpoint->ep_callbacks.rx)
            endpoint->ep_callbacks.rx(endpoint->ep_callbacks.priv,
                          skb, epid);
    }
}

struct htc_target *ath9k_htc_hw_alloc(void *hif_handle,
                      struct ath9k_htc_hif *hif,
                      struct device *dev)
{
    struct htc_endpoint *endpoint;
    struct htc_target *target;

    target = kzalloc(sizeof(struct htc_target), GFP_KERNEL);
    if (!target)
        return NULL;

    init_completion(&target->target_wait);
    init_completion(&target->cmd_wait);

    target->hif = hif;
    target->hif_dev = hif_handle;
    target->dev = dev;

    /* Assign control endpoint pipe IDs */
    endpoint = &target->endpoint[ENDPOINT0];
    endpoint->ul_pipeid = hif->control_ul_pipe;
    endpoint->dl_pipeid = hif->control_dl_pipe;

    atomic_set(&target->tgt_ready, 0);

    return target;
}

void ath9k_htc_hw_free(struct htc_target *htc)
{
    kfree(htc);
}

int ath9k_htc_hw_init(struct htc_target *target,
              struct device *dev, u16 devid,
              char *product, u32 drv_info)
{
    if (ath9k_htc_probe_device(target, dev, devid, product, drv_info)) {
        pr_err("Failed to initialize the device\n");
        return -ENODEV;
    }

    return 0;
}

void ath9k_htc_hw_deinit(struct htc_target *target, bool hot_unplug)
{
    if (target)
        ath9k_htc_disconnect_device(target, hot_unplug);
}