int msm_bam_dmux_open(uint32_t id, void *priv,
void (*receive_cb)(void *, struct sk_buff *),
void (*write_done)(void *, struct sk_buff *))
{
struct bam_mux_hdr *hdr;
unsigned long flags;
int rc = 0;
DBG("%s: opening ch %d\n", __func__, id);
if (!bam_mux_initialized)
return -ENODEV;
if (id >= BAM_DMUX_NUM_CHANNELS)
return -EINVAL;
hdr = kmalloc(sizeof(struct bam_mux_hdr), GFP_KERNEL);
if (hdr == NULL) {
pr_err("%s: hdr kmalloc failed. ch: %d\n", __func__, id);
return -ENOMEM;
}
spin_lock_irqsave(&bam_ch[id].lock, flags);
if (bam_ch_is_open(id)) {
DBG("%s: Already opened %d\n", __func__, id);
spin_unlock_irqrestore(&bam_ch[id].lock, flags);
kfree(hdr);
goto open_done;
}
if (!bam_ch_is_remote_open(id)) {
DBG("%s: Remote not open; ch: %d\n", __func__, id);
spin_unlock_irqrestore(&bam_ch[id].lock, flags);
kfree(hdr);
rc = -ENODEV;
goto open_done;
}
bam_ch[id].receive_cb = receive_cb;
bam_ch[id].write_done = write_done;
bam_ch[id].priv = priv;
bam_ch[id].status |= BAM_CH_LOCAL_OPEN;
spin_unlock_irqrestore(&bam_ch[id].lock, flags);
hdr->magic_num = BAM_MUX_HDR_MAGIC_NO;
hdr->cmd = BAM_MUX_HDR_CMD_OPEN;
hdr->reserved = 0;
hdr->ch_id = id;
hdr->pkt_len = 0;
hdr->pad_len = 0;
rc = bam_mux_write_cmd((void *)hdr, sizeof(struct bam_mux_hdr));
open_done:
DBG("%s: opened ch %d\n", __func__, id);
return rc;
}
int msm_bam_dmux_write(uint32_t id, struct sk_buff *skb)
{
int rc = 0;
struct bam_mux_hdr *hdr;
unsigned long flags;
struct sk_buff *new_skb = NULL;
dma_addr_t dma_address;
struct tx_pkt_info *pkt;
if (id >= BAM_DMUX_NUM_CHANNELS)
return -EINVAL;
if (!skb)
return -EINVAL;
if (!bam_mux_initialized)
return -ENODEV;
DBG("%s: writing to ch %d len %d\n", __func__, id, skb->len);
spin_lock_irqsave(&bam_ch[id].lock, flags);
if (!bam_ch_is_open(id)) {
spin_unlock_irqrestore(&bam_ch[id].lock, flags);
pr_err("%s: port not open: %d\n", __func__, bam_ch[id].status);
return -ENODEV;
}
spin_unlock_irqrestore(&bam_ch[id].lock, flags);
spin_lock_irqsave(&bam_mux_write_lock, flags);
/* if skb do not have any tailroom for padding,
copy the skb into a new expanded skb */
if ((skb->len & 0x3) && (skb_tailroom(skb) < (4 - (skb->len & 0x3)))) {
/* revisit, probably dev_alloc_skb and memcpy is effecient */
new_skb = skb_copy_expand(skb, skb_headroom(skb),
4 - (skb->len & 0x3), GFP_ATOMIC);
if (new_skb == NULL) {
pr_err("%s: cannot allocate skb\n", __func__);
rc = -ENOMEM;
goto write_done;
}
dev_kfree_skb_any(skb);
skb = new_skb;
DBG_INC_WRITE_CPY(skb->len);
}
hdr = (struct bam_mux_hdr *)skb_push(skb, sizeof(struct bam_mux_hdr));
/* caller should allocate for hdr and padding
hdr is fine, padding is tricky */
hdr->magic_num = BAM_MUX_HDR_MAGIC_NO;
hdr->cmd = BAM_MUX_HDR_CMD_DATA;
hdr->reserved = 0;
hdr->ch_id = id;
hdr->pkt_len = skb->len - sizeof(struct bam_mux_hdr);
if (skb->len & 0x3)
skb_put(skb, 4 - (skb->len & 0x3));
hdr->pad_len = skb->len - (sizeof(struct bam_mux_hdr) + hdr->pkt_len);
DBG("%s: data %p, tail %p skb len %d pkt len %d pad len %d\n",
__func__, skb->data, skb->tail, skb->len,
hdr->pkt_len, hdr->pad_len);
pkt = kmalloc(sizeof(struct tx_pkt_info), GFP_ATOMIC);
if (pkt == NULL) {
pr_err("%s: mem alloc for tx_pkt_info failed\n", __func__);
if (new_skb)
dev_kfree_skb_any(new_skb);
rc = -ENOMEM;
goto write_done;
}
dma_address = dma_map_single(NULL, skb->data, skb->len,
DMA_TO_DEVICE);
if (!dma_address) {
pr_err("%s: dma_map_single() failed\n", __func__);
if (new_skb)
dev_kfree_skb_any(new_skb);
kfree(pkt);
rc = -ENOMEM;
goto write_done;
}
pkt->skb = skb;
pkt->dma_address = dma_address;
pkt->is_cmd = 0;
spin_unlock_irqrestore(&bam_mux_write_lock, flags);
rc = sps_transfer_one(bam_tx_pipe, dma_address, skb->len,
pkt, SPS_IOVEC_FLAG_INT | SPS_IOVEC_FLAG_EOT);
return rc;
write_done:
spin_unlock_irqrestore(&bam_mux_write_lock, flags);
return rc;
}
