On Thu, Feb 24, 2022 at 1:35 AM Ricardo Martinez
<ricardo.martinez@xxxxxxxxxxxxxxx> wrote:
> From: Chandrashekar Devegowda <chandrashekar.devegowda@xxxxxxxxx>
>
> Adds AT and MBIM ports to the port proxy infrastructure.
> The initialization method is responsible for creating the corresponding
> ports using the WWAN framework infrastructure. The implemented WWAN port
> operations are start, stop, and TX.
[skipped]
> +static int t7xx_port_ctrl_tx(struct wwan_port *port, struct sk_buff *skb)
> +{
> + struct t7xx_port *port_private = wwan_port_get_drvdata(port);
> + size_t actual_len, alloc_size, txq_mtu = CLDMA_MTU;
> + struct t7xx_port_static *port_static;
> + unsigned int len, i, packets;
> + struct t7xx_fsm_ctl *ctl;
> + enum md_state md_state;
> +
> + len = skb->len;
> + if (!len || !port_private->rx_length_th || !port_private->chan_enable)
> + return -EINVAL;
> +
> + port_static = port_private->port_static;
> + ctl = port_private->t7xx_dev->md->fsm_ctl;
> + md_state = t7xx_fsm_get_md_state(ctl);
> + if (md_state == MD_STATE_WAITING_FOR_HS1 || md_state == MD_STATE_WAITING_FOR_HS2) {
> + dev_warn(port_private->dev, "Cannot write to %s port when md_state=%d\n",
> + port_static->name, md_state);
> + return -ENODEV;
> + }
> +
> + alloc_size = min_t(size_t, txq_mtu, len + CCCI_HEADROOM);
> + actual_len = alloc_size - CCCI_HEADROOM;
> + packets = DIV_ROUND_UP(len, txq_mtu - CCCI_HEADROOM);
> +
> + for (i = 0; i < packets; i++) {
> + struct ccci_header *ccci_h;
> + struct sk_buff *skb_ccci;
> + int ret;
> +
> + if (packets > 1 && packets == i + 1) {
> + actual_len = len % (txq_mtu - CCCI_HEADROOM);
> + alloc_size = actual_len + CCCI_HEADROOM;
> + }
Why do you track the packet number? Why not track the offset in the
passed data? E.g.:
for (off = 0; off < len; off += chunklen) {
chunklen = min(len - off, CLDMA_MTU - sizeof(struct ccci_header);
skb_ccci = alloc_skb(chunklen + sizeof(struct ccci_header), ...);
skb_put_data(skb_ccci, skb->data + off, chunklen);
/* Send skb_ccci */
}
> + skb_ccci = __dev_alloc_skb(alloc_size, GFP_KERNEL);
> + if (!skb_ccci)
> + return -ENOMEM;
> +
> + ccci_h = skb_put(skb_ccci, sizeof(*ccci_h));
> + t7xx_ccci_header_init(ccci_h, 0, actual_len + sizeof(*ccci_h),
> + port_static->tx_ch, 0);
> + skb_put_data(skb_ccci, skb->data + i * (txq_mtu - CCCI_HEADROOM), actual_len);
> + t7xx_port_proxy_set_tx_seq_num(port_private, ccci_h);
> +
> + ret = t7xx_port_send_skb_to_md(port_private, skb_ccci);
> + if (ret) {
> + dev_kfree_skb_any(skb_ccci);
> + dev_err(port_private->dev, "Write error on %s port, %d\n",
> + port_static->name, ret);
> + return ret;
> + }
> +
> + port_private->seq_nums[MTK_TX]++;
Sequence number tracking as well as CCCI header construction are
common operations, so why not move them to t7xx_port_send_skb_to_md()?
> + }
> +
> + dev_kfree_skb(skb);
> + return 0;
> +}
--
Sergey
