Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  Shared Transport Line discipline driver Core
 *	This hooks up ST KIM driver and ST LL driver
 *  Copyright (C) 2009-2010 Texas Instruments
 *  Author: Pavan Savoy <pavan_savoy@ti.com>
 */
 
#define pr_fmt(fmt)	"(stc): " fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/tty.h>
 
#include <linux/seq_file.h>
#include <linux/skbuff.h>
 
#include <linux/ti_wilink_st.h>
 
extern void st_kim_recv(void *, const unsigned char *, long);
void st_int_recv(void *, const unsigned char *, long);
/*
 * function pointer pointing to either,
 * st_kim_recv during registration to receive fw download responses
 * st_int_recv after registration to receive proto stack responses
 */
static void (*st_recv) (void *, const unsigned char *, long);
 
/********************************************************************/
static void add_channel_to_table(struct st_data_s *st_gdata,
<------><------>struct st_proto_s *new_proto)
{
<------>pr_info("%s: id %d\n", __func__, new_proto->chnl_id);
<------>/* list now has the channel id as index itself */
<------>st_gdata->list[new_proto->chnl_id] = new_proto;
<------>st_gdata->is_registered[new_proto->chnl_id] = true;
}
 
static void remove_channel_from_table(struct st_data_s *st_gdata,
<------><------>struct st_proto_s *proto)
{
<------>pr_info("%s: id %d\n", __func__, proto->chnl_id);
/*	st_gdata->list[proto->chnl_id] = NULL; */
<------>st_gdata->is_registered[proto->chnl_id] = false;
}
 
/*
 * called from KIM during firmware download.
 *
 * This is a wrapper function to tty->ops->write_room.
 * It returns number of free space available in
 * uart tx buffer.
 */
int st_get_uart_wr_room(struct st_data_s *st_gdata)
{
<------>struct tty_struct *tty;
<------>if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) {
<------><------>pr_err("tty unavailable to perform write");
<------><------>return -1;
<------>}
<------>tty = st_gdata->tty;
<------>return tty->ops->write_room(tty);
}
 
/*
 * can be called in from
 * -- KIM (during fw download)
 * -- ST Core (during st_write)
 *
 *  This is the internal write function - a wrapper
 *  to tty->ops->write
 */
int st_int_write(struct st_data_s *st_gdata,
<------>const unsigned char *data, int count)
{
<------>struct tty_struct *tty;
<------>if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) {
<------><------>pr_err("tty unavailable to perform write");
<------><------>return -EINVAL;
<------>}
<------>tty = st_gdata->tty;
#ifdef VERBOSE
<------>print_hex_dump(KERN_DEBUG, "<out<", DUMP_PREFIX_NONE,
<------><------>16, 1, data, count, 0);
#endif
<------>return tty->ops->write(tty, data, count);
 
}
 
/*
 * push the skb received to relevant
 * protocol stacks
 */
static void st_send_frame(unsigned char chnl_id, struct st_data_s *st_gdata)
{
<------>pr_debug(" %s(prot:%d) ", __func__, chnl_id);
 
<------>if (unlikely
<------>    (st_gdata == NULL || st_gdata->rx_skb == NULL
<------>     || st_gdata->is_registered[chnl_id] == false)) {
<------><------>pr_err("chnl_id %d not registered, no data to send?",
<------><------><------>   chnl_id);
<------><------>kfree_skb(st_gdata->rx_skb);
<------><------>return;
<------>}
<------>/*
<------> * this cannot fail
<------> * this shouldn't take long
<------> * - should be just skb_queue_tail for the
<------> *   protocol stack driver
<------> */
<------>if (likely(st_gdata->list[chnl_id]->recv != NULL)) {
<------><------>if (unlikely
<------><------><------>(st_gdata->list[chnl_id]->recv
<------><------><------>(st_gdata->list[chnl_id]->priv_data, st_gdata->rx_skb)
<------><------><------>     != 0)) {
<------><------><------>pr_err(" proto stack %d's ->recv failed", chnl_id);
<------><------><------>kfree_skb(st_gdata->rx_skb);
<------><------><------>return;
<------><------>}
<------>} else {
<------><------>pr_err(" proto stack %d's ->recv null", chnl_id);
<------><------>kfree_skb(st_gdata->rx_skb);
<------>}
<------>return;
}
 
/*
 * st_reg_complete - to call registration complete callbacks
 * of all protocol stack drivers
 * This function is being called with spin lock held, protocol drivers are
 * only expected to complete their waits and do nothing more than that.
 */
static void st_reg_complete(struct st_data_s *st_gdata, int err)
{
<------>unsigned char i = 0;
<------>pr_info(" %s ", __func__);
<------>for (i = 0; i < ST_MAX_CHANNELS; i++) {
<------><------>if (likely(st_gdata != NULL &&
<------><------><------>st_gdata->is_registered[i] == true &&
<------><------><------><------>st_gdata->list[i]->reg_complete_cb != NULL)) {
<------><------><------>st_gdata->list[i]->reg_complete_cb
<------><------><------><------>(st_gdata->list[i]->priv_data, err);
<------><------><------>pr_info("protocol %d's cb sent %d\n", i, err);
<------><------><------>if (err) { /* cleanup registered protocol */
<------><------><------><------>st_gdata->is_registered[i] = false;
<------><------><------><------>if (st_gdata->protos_registered)
<------><------><------><------><------>st_gdata->protos_registered--;
<------><------><------>}
<------><------>}
<------>}
}
 
static inline int st_check_data_len(struct st_data_s *st_gdata,
<------>unsigned char chnl_id, int len)
{
<------>int room = skb_tailroom(st_gdata->rx_skb);
 
<------>pr_debug("len %d room %d", len, room);
 
<------>if (!len) {
<------><------>/*
<------><------> * Received packet has only packet header and
<------><------> * has zero length payload. So, ask ST CORE to
<------><------> * forward the packet to protocol driver (BT/FM/GPS)
<------><------> */
<------><------>st_send_frame(chnl_id, st_gdata);
 
<------>} else if (len > room) {
<------><------>/*
<------><------> * Received packet's payload length is larger.
<------><------> * We can't accommodate it in created skb.
<------><------> */
<------><------>pr_err("Data length is too large len %d room %d", len,
<------><------><------>   room);
<------><------>kfree_skb(st_gdata->rx_skb);
<------>} else {
<------><------>/*
<------><------> * Packet header has non-zero payload length and
<------><------> * we have enough space in created skb. Lets read
<------><------> * payload data */
<------><------>st_gdata->rx_state = ST_W4_DATA;
<------><------>st_gdata->rx_count = len;
<------><------>return len;
<------>}
 
<------>/* Change ST state to continue to process next packet */
<------>st_gdata->rx_state = ST_W4_PACKET_TYPE;
<------>st_gdata->rx_skb = NULL;
<------>st_gdata->rx_count = 0;
<------>st_gdata->rx_chnl = 0;
 
<------>return 0;
}
 
/*
 * st_wakeup_ack - internal function for action when wake-up ack
 *	received
 */
static inline void st_wakeup_ack(struct st_data_s *st_gdata,
<------>unsigned char cmd)
{
<------>struct sk_buff *waiting_skb;
<------>unsigned long flags = 0;
 
<------>spin_lock_irqsave(&st_gdata->lock, flags);
<------>/*
<------> * de-Q from waitQ and Q in txQ now that the
<------> * chip is awake
<------> */
<------>while ((waiting_skb = skb_dequeue(&st_gdata->tx_waitq)))
<------><------>skb_queue_tail(&st_gdata->txq, waiting_skb);
 
<------>/* state forwarded to ST LL */
<------>st_ll_sleep_state(st_gdata, (unsigned long)cmd);
<------>spin_unlock_irqrestore(&st_gdata->lock, flags);
 
<------>/* wake up to send the recently copied skbs from waitQ */
<------>st_tx_wakeup(st_gdata);
}
 
/*
 * st_int_recv - ST's internal receive function.
 *	Decodes received RAW data and forwards to corresponding
 *	client drivers (Bluetooth,FM,GPS..etc).
 *	This can receive various types of packets,
 *	HCI-Events, ACL, SCO, 4 types of HCI-LL PM packets
 *	CH-8 packets from FM, CH-9 packets from GPS cores.
 */
void st_int_recv(void *disc_data,
<------>const unsigned char *data, long count)
{
<------>char *ptr;
<------>struct st_proto_s *proto;
<------>unsigned short payload_len = 0;
<------>int len = 0;
<------>unsigned char type = 0;
<------>unsigned char *plen;
<------>struct st_data_s *st_gdata = (struct st_data_s *)disc_data;
<------>unsigned long flags;
 
<------>ptr = (char *)data;
<------>/* tty_receive sent null ? */
<------>if (unlikely(ptr == NULL) || (st_gdata == NULL)) {
<------><------>pr_err(" received null from TTY ");
<------><------>return;
<------>}
 
<------>pr_debug("count %ld rx_state %ld"
<------><------>   "rx_count %ld", count, st_gdata->rx_state,
<------><------>   st_gdata->rx_count);
 
<------>spin_lock_irqsave(&st_gdata->lock, flags);
<------>/* Decode received bytes here */
<------>while (count) {
<------><------>if (st_gdata->rx_count) {
<------><------><------>len = min_t(unsigned int, st_gdata->rx_count, count);
<------><------><------>skb_put_data(st_gdata->rx_skb, ptr, len);
<------><------><------>st_gdata->rx_count -= len;
<------><------><------>count -= len;
<------><------><------>ptr += len;
 
<------><------><------>if (st_gdata->rx_count)
<------><------><------><------>continue;
 
<------><------><------>/* Check ST RX state machine , where are we? */
<------><------><------>switch (st_gdata->rx_state) {
<------><------><------>/* Waiting for complete packet ? */
<------><------><------>case ST_W4_DATA:
<------><------><------><------>pr_debug("Complete pkt received");
<------><------><------><------>/*
<------><------><------><------> * Ask ST CORE to forward
<------><------><------><------> * the packet to protocol driver
<------><------><------><------> */
<------><------><------><------>st_send_frame(st_gdata->rx_chnl, st_gdata);
 
<------><------><------><------>st_gdata->rx_state = ST_W4_PACKET_TYPE;
<------><------><------><------>st_gdata->rx_skb = NULL;
<------><------><------><------>continue;
<------><------><------>/* parse the header to know details */
<------><------><------>case ST_W4_HEADER:
<------><------><------><------>proto = st_gdata->list[st_gdata->rx_chnl];
<------><------><------><------>plen =
<------><------><------><------>&st_gdata->rx_skb->data
<------><------><------><------>[proto->offset_len_in_hdr];
<------><------><------><------>pr_debug("plen pointing to %x\n", *plen);
<------><------><------><------>if (proto->len_size == 1) /* 1 byte len field */
<------><------><------><------><------>payload_len = *(unsigned char *)plen;
<------><------><------><------>else if (proto->len_size == 2)
<------><------><------><------><------>payload_len =
<------><------><------><------><------>__le16_to_cpu(*(unsigned short *)plen);
<------><------><------><------>else
<------><------><------><------><------>pr_info("%s: invalid length "
<------><------><------><------><------>"for id %d\n",
<------><------><------><------><------>__func__, proto->chnl_id);
<------><------><------><------>st_check_data_len(st_gdata, proto->chnl_id,
<------><------><------><------><------><------>payload_len);
<------><------><------><------>pr_debug("off %d, pay len %d\n",
<------><------><------><------><------>proto->offset_len_in_hdr, payload_len);
<------><------><------><------>continue;
<------><------><------>}	/* end of switch rx_state */
<------><------>}
 
<------><------>/* end of if rx_count */
 
<------><------>/*
<------><------> * Check first byte of packet and identify module
<------><------> * owner (BT/FM/GPS)
<------><------> */
<------><------>switch (*ptr) {
<------><------>case LL_SLEEP_IND:
<------><------>case LL_SLEEP_ACK:
<------><------>case LL_WAKE_UP_IND:
<------><------><------>pr_debug("PM packet");
<------><------><------>/*
<------><------><------> * this takes appropriate action based on
<------><------><------> * sleep state received --
<------><------><------> */
<------><------><------>st_ll_sleep_state(st_gdata, *ptr);
<------><------><------>/*
<------><------><------> * if WAKEUP_IND collides copy from waitq to txq
<------><------><------> * and assume chip awake
<------><------><------> */
<------><------><------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------><------><------>if (st_ll_getstate(st_gdata) == ST_LL_AWAKE)
<------><------><------><------>st_wakeup_ack(st_gdata, LL_WAKE_UP_ACK);
<------><------><------>spin_lock_irqsave(&st_gdata->lock, flags);
 
<------><------><------>ptr++;
<------><------><------>count--;
<------><------><------>continue;
<------><------>case LL_WAKE_UP_ACK:
<------><------><------>pr_debug("PM packet");
 
<------><------><------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------><------><------>/* wake up ack received */
<------><------><------>st_wakeup_ack(st_gdata, *ptr);
<------><------><------>spin_lock_irqsave(&st_gdata->lock, flags);
 
<------><------><------>ptr++;
<------><------><------>count--;
<------><------><------>continue;
<------><------><------>/* Unknow packet? */
<------><------>default:
<------><------><------>type = *ptr;
 
<------><------><------>/*
<------><------><------> * Default case means non-HCILL packets,
<------><------><------> * possibilities are packets for:
<------><------><------> * (a) valid protocol -  Supported Protocols within
<------><------><------> *     the ST_MAX_CHANNELS.
<------><------><------> * (b) registered protocol - Checked by
<------><------><------> *     "st_gdata->list[type] == NULL)" are supported
<------><------><------> *     protocols only.
<------><------><------> *  Rules out any invalid protocol and
<------><------><------> *  unregistered protocols with channel ID < 16.
<------><------><------> */
 
<------><------><------>if ((type >= ST_MAX_CHANNELS) ||
<------><------><------><------><------>(st_gdata->list[type] == NULL)) {
<------><------><------><------>pr_err("chip/interface misbehavior: "
<------><------><------><------><------><------>"dropping frame starting "
<------><------><------><------><------><------>"with 0x%02x\n", type);
<------><------><------><------>goto done;
<------><------><------>}
 
<------><------><------>st_gdata->rx_skb = alloc_skb(
<------><------><------><------><------>st_gdata->list[type]->max_frame_size,
<------><------><------><------><------>GFP_ATOMIC);
<------><------><------>if (st_gdata->rx_skb == NULL) {
<------><------><------><------>pr_err("out of memory: dropping\n");
<------><------><------><------>goto done;
<------><------><------>}
 
<------><------><------>skb_reserve(st_gdata->rx_skb,
<------><------><------><------><------>st_gdata->list[type]->reserve);
<------><------><------>/* next 2 required for BT only */
<------><------><------>st_gdata->rx_skb->cb[0] = type; /*pkt_type*/
<------><------><------>st_gdata->rx_skb->cb[1] = 0; /*incoming*/
<------><------><------>st_gdata->rx_chnl = *ptr;
<------><------><------>st_gdata->rx_state = ST_W4_HEADER;
<------><------><------>st_gdata->rx_count = st_gdata->list[type]->hdr_len;
<------><------><------>pr_debug("rx_count %ld\n", st_gdata->rx_count);
<------><------>};
<------><------>ptr++;
<------><------>count--;
<------>}
done:
<------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------>pr_debug("done %s", __func__);
<------>return;
}
 
/*
 * st_int_dequeue - internal de-Q function.
 *	If the previous data set was not written
 *	completely, return that skb which has the pending data.
 *	In normal cases, return top of txq.
 */
static struct sk_buff *st_int_dequeue(struct st_data_s *st_gdata)
{
<------>struct sk_buff *returning_skb;
 
<------>pr_debug("%s", __func__);
<------>if (st_gdata->tx_skb != NULL) {
<------><------>returning_skb = st_gdata->tx_skb;
<------><------>st_gdata->tx_skb = NULL;
<------><------>return returning_skb;
<------>}
<------>return skb_dequeue(&st_gdata->txq);
}
 
/*
 * st_int_enqueue - internal Q-ing function.
 *	Will either Q the skb to txq or the tx_waitq
 *	depending on the ST LL state.
 *	If the chip is asleep, then Q it onto waitq and
 *	wakeup the chip.
 *	txq and waitq needs protection since the other contexts
 *	may be sending data, waking up chip.
 */
static void st_int_enqueue(struct st_data_s *st_gdata, struct sk_buff *skb)
{
<------>unsigned long flags = 0;
 
<------>pr_debug("%s", __func__);
<------>spin_lock_irqsave(&st_gdata->lock, flags);
 
<------>switch (st_ll_getstate(st_gdata)) {
<------>case ST_LL_AWAKE:
<------><------>pr_debug("ST LL is AWAKE, sending normally");
<------><------>skb_queue_tail(&st_gdata->txq, skb);
<------><------>break;
<------>case ST_LL_ASLEEP_TO_AWAKE:
<------><------>skb_queue_tail(&st_gdata->tx_waitq, skb);
<------><------>break;
<------>case ST_LL_AWAKE_TO_ASLEEP:
<------><------>pr_err("ST LL is illegal state(%ld),"
<------><------><------>   "purging received skb.", st_ll_getstate(st_gdata));
<------><------>kfree_skb(skb);
<------><------>break;
<------>case ST_LL_ASLEEP:
<------><------>skb_queue_tail(&st_gdata->tx_waitq, skb);
<------><------>st_ll_wakeup(st_gdata);
<------><------>break;
<------>default:
<------><------>pr_err("ST LL is illegal state(%ld),"
<------><------><------>   "purging received skb.", st_ll_getstate(st_gdata));
<------><------>kfree_skb(skb);
<------><------>break;
<------>}
 
<------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------>pr_debug("done %s", __func__);
<------>return;
}
 
/*
 * internal wakeup function
 * called from either
 * - TTY layer when write's finished
 * - st_write (in context of the protocol stack)
 */
static void work_fn_write_wakeup(struct work_struct *work)
{
<------>struct st_data_s *st_gdata = container_of(work, struct st_data_s,
<------><------><------>work_write_wakeup);
 
<------>st_tx_wakeup((void *)st_gdata);
}
void st_tx_wakeup(struct st_data_s *st_data)
{
<------>struct sk_buff *skb;
<------>unsigned long flags;	/* for irq save flags */
<------>pr_debug("%s", __func__);
<------>/* check for sending & set flag sending here */
<------>if (test_and_set_bit(ST_TX_SENDING, &st_data->tx_state)) {
<------><------>pr_debug("ST already sending");
<------><------>/* keep sending */
<------><------>set_bit(ST_TX_WAKEUP, &st_data->tx_state);
<------><------>return;
<------><------>/* TX_WAKEUP will be checked in another
<------><------> * context
<------><------> */
<------>}
<------>do {			/* come back if st_tx_wakeup is set */
<------><------>/* woke-up to write */
<------><------>clear_bit(ST_TX_WAKEUP, &st_data->tx_state);
<------><------>while ((skb = st_int_dequeue(st_data))) {
<------><------><------>int len;
<------><------><------>spin_lock_irqsave(&st_data->lock, flags);
<------><------><------>/* enable wake-up from TTY */
<------><------><------>set_bit(TTY_DO_WRITE_WAKEUP, &st_data->tty->flags);
<------><------><------>len = st_int_write(st_data, skb->data, skb->len);
<------><------><------>skb_pull(skb, len);
<------><------><------>/* if skb->len = len as expected, skb->len=0 */
<------><------><------>if (skb->len) {
<------><------><------><------>/* would be the next skb to be sent */
<------><------><------><------>st_data->tx_skb = skb;
<------><------><------><------>spin_unlock_irqrestore(&st_data->lock, flags);
<------><------><------><------>break;
<------><------><------>}
<------><------><------>kfree_skb(skb);
<------><------><------>spin_unlock_irqrestore(&st_data->lock, flags);
<------><------>}
<------><------>/* if wake-up is set in another context- restart sending */
<------>} while (test_bit(ST_TX_WAKEUP, &st_data->tx_state));
 
<------>/* clear flag sending */
<------>clear_bit(ST_TX_SENDING, &st_data->tx_state);
}
 
/********************************************************************/
/* functions called from ST KIM
*/
void kim_st_list_protocols(struct st_data_s *st_gdata, void *buf)
{
<------>seq_printf(buf, "[%d]\nBT=%c\nFM=%c\nGPS=%c\n",
<------><------><------>st_gdata->protos_registered,
<------><------><------>st_gdata->is_registered[0x04] == true ? 'R' : 'U',
<------><------><------>st_gdata->is_registered[0x08] == true ? 'R' : 'U',
<------><------><------>st_gdata->is_registered[0x09] == true ? 'R' : 'U');
}
 
/********************************************************************/
/*
 * functions called from protocol stack drivers
 * to be EXPORT-ed
 */
long st_register(struct st_proto_s *new_proto)
{
<------>struct st_data_s	*st_gdata;
<------>long err = 0;
<------>unsigned long flags = 0;
 
<------>st_kim_ref(&st_gdata, 0);
<------>if (st_gdata == NULL || new_proto == NULL || new_proto->recv == NULL
<------>    || new_proto->reg_complete_cb == NULL) {
<------><------>pr_err("gdata/new_proto/recv or reg_complete_cb not ready");
<------><------>return -EINVAL;
<------>}
 
<------>if (new_proto->chnl_id >= ST_MAX_CHANNELS) {
<------><------>pr_err("chnl_id %d not supported", new_proto->chnl_id);
<------><------>return -EPROTONOSUPPORT;
<------>}
 
<------>if (st_gdata->is_registered[new_proto->chnl_id] == true) {
<------><------>pr_err("chnl_id %d already registered", new_proto->chnl_id);
<------><------>return -EALREADY;
<------>}
 
<------>/* can be from process context only */
<------>spin_lock_irqsave(&st_gdata->lock, flags);
 
<------>if (test_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state)) {
<------><------>pr_info(" ST_REG_IN_PROGRESS:%d ", new_proto->chnl_id);
<------><------>/* fw download in progress */
 
<------><------>add_channel_to_table(st_gdata, new_proto);
<------><------>st_gdata->protos_registered++;
<------><------>new_proto->write = st_write;
 
<------><------>set_bit(ST_REG_PENDING, &st_gdata->st_state);
<------><------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------><------>return -EINPROGRESS;
<------>} else if (st_gdata->protos_registered == ST_EMPTY) {
<------><------>pr_info(" chnl_id list empty :%d ", new_proto->chnl_id);
<------><------>set_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state);
<------><------>st_recv = st_kim_recv;
 
<------><------>/* enable the ST LL - to set default chip state */
<------><------>st_ll_enable(st_gdata);
 
<------><------>/* release lock previously held - re-locked below */
<------><------>spin_unlock_irqrestore(&st_gdata->lock, flags);
 
<------><------>/*
<------><------> * this may take a while to complete
<------><------> * since it involves BT fw download
<------><------> */
<------><------>err = st_kim_start(st_gdata->kim_data);
<------><------>if (err != 0) {
<------><------><------>clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state);
<------><------><------>if ((st_gdata->protos_registered != ST_EMPTY) &&
<------><------><------>    (test_bit(ST_REG_PENDING, &st_gdata->st_state))) {
<------><------><------><------>pr_err(" KIM failure complete callback ");
<------><------><------><------>spin_lock_irqsave(&st_gdata->lock, flags);
<------><------><------><------>st_reg_complete(st_gdata, err);
<------><------><------><------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------><------><------><------>clear_bit(ST_REG_PENDING, &st_gdata->st_state);
<------><------><------>}
<------><------><------>return -EINVAL;
<------><------>}
 
<------><------>spin_lock_irqsave(&st_gdata->lock, flags);
 
<------><------>clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state);
<------><------>st_recv = st_int_recv;
 
<------><------>/*
<------><------> * this is where all pending registration
<------><------> * are signalled to be complete by calling callback functions
<------><------> */
<------><------>if ((st_gdata->protos_registered != ST_EMPTY) &&
<------><------>    (test_bit(ST_REG_PENDING, &st_gdata->st_state))) {
<------><------><------>pr_debug(" call reg complete callback ");
<------><------><------>st_reg_complete(st_gdata, 0);
<------><------>}
<------><------>clear_bit(ST_REG_PENDING, &st_gdata->st_state);
 
<------><------>/*
<------><------> * check for already registered once more,
<------><------> * since the above check is old
<------><------> */
<------><------>if (st_gdata->is_registered[new_proto->chnl_id] == true) {
<------><------><------>pr_err(" proto %d already registered ",
<------><------><------><------>   new_proto->chnl_id);
<------><------><------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------><------><------>return -EALREADY;
<------><------>}
 
<------><------>add_channel_to_table(st_gdata, new_proto);
<------><------>st_gdata->protos_registered++;
<------><------>new_proto->write = st_write;
<------><------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------><------>return err;
<------>}
<------>/* if fw is already downloaded & new stack registers protocol */
<------>else {
<------><------>add_channel_to_table(st_gdata, new_proto);
<------><------>st_gdata->protos_registered++;
<------><------>new_proto->write = st_write;
 
<------><------>/* lock already held before entering else */
<------><------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------><------>return err;
<------>}
}
EXPORT_SYMBOL_GPL(st_register);
 
/*
 * to unregister a protocol -
 * to be called from protocol stack driver
 */
long st_unregister(struct st_proto_s *proto)
{
<------>long err = 0;
<------>unsigned long flags = 0;
<------>struct st_data_s	*st_gdata;
 
<------>pr_debug("%s: %d ", __func__, proto->chnl_id);
 
<------>st_kim_ref(&st_gdata, 0);
<------>if (!st_gdata || proto->chnl_id >= ST_MAX_CHANNELS) {
<------><------>pr_err(" chnl_id %d not supported", proto->chnl_id);
<------><------>return -EPROTONOSUPPORT;
<------>}
 
<------>spin_lock_irqsave(&st_gdata->lock, flags);
 
<------>if (st_gdata->is_registered[proto->chnl_id] == false) {
<------><------>pr_err(" chnl_id %d not registered", proto->chnl_id);
<------><------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------><------>return -EPROTONOSUPPORT;
<------>}
 
<------>if (st_gdata->protos_registered)
<------><------>st_gdata->protos_registered--;
 
<------>remove_channel_from_table(st_gdata, proto);
<------>spin_unlock_irqrestore(&st_gdata->lock, flags);
 
<------>if ((st_gdata->protos_registered == ST_EMPTY) &&
<------>    (!test_bit(ST_REG_PENDING, &st_gdata->st_state))) {
<------><------>pr_info(" all chnl_ids unregistered ");
 
<------><------>/* stop traffic on tty */
<------><------>if (st_gdata->tty) {
<------><------><------>tty_ldisc_flush(st_gdata->tty);
<------><------><------>stop_tty(st_gdata->tty);
<------><------>}
 
<------><------>/* all chnl_ids now unregistered */
<------><------>st_kim_stop(st_gdata->kim_data);
<------><------>/* disable ST LL */
<------><------>st_ll_disable(st_gdata);
<------>}
<------>return err;
}
 
/*
 * called in protocol stack drivers
 * via the write function pointer
 */
long st_write(struct sk_buff *skb)
{
<------>struct st_data_s *st_gdata;
<------>long len;
 
<------>st_kim_ref(&st_gdata, 0);
<------>if (unlikely(skb == NULL || st_gdata == NULL
<------><------>|| st_gdata->tty == NULL)) {
<------><------>pr_err("data/tty unavailable to perform write");
<------><------>return -EINVAL;
<------>}
 
<------>pr_debug("%d to be written", skb->len);
<------>len = skb->len;
 
<------>/* st_ll to decide where to enqueue the skb */
<------>st_int_enqueue(st_gdata, skb);
<------>/* wake up */
<------>st_tx_wakeup(st_gdata);
 
<------>/* return number of bytes written */
<------>return len;
}
 
/* for protocols making use of shared transport */
EXPORT_SYMBOL_GPL(st_unregister);
 
/********************************************************************/
/*
 * functions called from TTY layer
 */
static int st_tty_open(struct tty_struct *tty)
{
<------>struct st_data_s *st_gdata;
<------>pr_info("%s ", __func__);
 
<------>st_kim_ref(&st_gdata, 0);
<------>st_gdata->tty = tty;
<------>tty->disc_data = st_gdata;
 
<------>/* don't do an wakeup for now */
<------>clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
 
<------>/* mem already allocated
<------> */
<------>tty->receive_room = 65536;
<------>/* Flush any pending characters in the driver and discipline. */
<------>tty_ldisc_flush(tty);
<------>tty_driver_flush_buffer(tty);
<------>/*
<------> * signal to UIM via KIM that -
<------> * installation of N_TI_WL ldisc is complete
<------> */
<------>st_kim_complete(st_gdata->kim_data);
<------>pr_debug("done %s", __func__);
 
<------>return 0;
}
 
static void st_tty_close(struct tty_struct *tty)
{
<------>unsigned char i;
<------>unsigned long flags;
<------>struct	st_data_s *st_gdata = tty->disc_data;
 
<------>pr_info("%s ", __func__);
 
<------>/*
<------> * TODO:
<------> * if a protocol has been registered & line discipline
<------> * un-installed for some reason - what should be done ?
<------> */
<------>spin_lock_irqsave(&st_gdata->lock, flags);
<------>for (i = ST_BT; i < ST_MAX_CHANNELS; i++) {
<------><------>if (st_gdata->is_registered[i] == true)
<------><------><------>pr_err("%d not un-registered", i);
<------><------>st_gdata->list[i] = NULL;
<------><------>st_gdata->is_registered[i] = false;
<------>}
<------>st_gdata->protos_registered = 0;
<------>spin_unlock_irqrestore(&st_gdata->lock, flags);
<------>/*
<------> * signal to UIM via KIM that -
<------> * N_TI_WL ldisc is un-installed
<------> */
<------>st_kim_complete(st_gdata->kim_data);
<------>st_gdata->tty = NULL;
<------>/* Flush any pending characters in the driver and discipline. */
<------>tty_ldisc_flush(tty);
<------>tty_driver_flush_buffer(tty);
 
<------>spin_lock_irqsave(&st_gdata->lock, flags);
<------>/* empty out txq and tx_waitq */
<------>skb_queue_purge(&st_gdata->txq);
<------>skb_queue_purge(&st_gdata->tx_waitq);
<------>/* reset the TTY Rx states of ST */
<------>st_gdata->rx_count = 0;
<------>st_gdata->rx_state = ST_W4_PACKET_TYPE;
<------>kfree_skb(st_gdata->rx_skb);
<------>st_gdata->rx_skb = NULL;
<------>spin_unlock_irqrestore(&st_gdata->lock, flags);
 
<------>pr_debug("%s: done ", __func__);
}
 
static void st_tty_receive(struct tty_struct *tty, const unsigned char *data,
<------><------><------>   char *tty_flags, int count)
{
#ifdef VERBOSE
<------>print_hex_dump(KERN_DEBUG, ">in>", DUMP_PREFIX_NONE,
<------><------>16, 1, data, count, 0);
#endif
 
<------>/*
<------> * if fw download is in progress then route incoming data
<------> * to KIM for validation
<------> */
<------>st_recv(tty->disc_data, data, count);
<------>pr_debug("done %s", __func__);
}
 
/*
 * wake-up function called in from the TTY layer
 * inside the internal wakeup function will be called
 */
static void st_tty_wakeup(struct tty_struct *tty)
{
<------>struct	st_data_s *st_gdata = tty->disc_data;
<------>pr_debug("%s ", __func__);
<------>/* don't do an wakeup for now */
<------>clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
 
<------>/*
<------> * schedule the internal wakeup instead of calling directly to
<------> * avoid lockup (port->lock needed in tty->ops->write is
<------> * already taken here
<------> */
<------>schedule_work(&st_gdata->work_write_wakeup);
}
 
static void st_tty_flush_buffer(struct tty_struct *tty)
{
<------>struct	st_data_s *st_gdata = tty->disc_data;
<------>pr_debug("%s ", __func__);
 
<------>kfree_skb(st_gdata->tx_skb);
<------>st_gdata->tx_skb = NULL;
 
<------>tty_driver_flush_buffer(tty);
<------>return;
}
 
static struct tty_ldisc_ops st_ldisc_ops = {
<------>.magic = TTY_LDISC_MAGIC,
<------>.name = "n_st",
<------>.open = st_tty_open,
<------>.close = st_tty_close,
<------>.receive_buf = st_tty_receive,
<------>.write_wakeup = st_tty_wakeup,
<------>.flush_buffer = st_tty_flush_buffer,
<------>.owner = THIS_MODULE
};
 
/********************************************************************/
int st_core_init(struct st_data_s **core_data)
{
<------>struct st_data_s *st_gdata;
<------>long err;
 
<------>err = tty_register_ldisc(N_TI_WL, &st_ldisc_ops);
<------>if (err) {
<------><------>pr_err("error registering %d line discipline %ld",
<------><------><------>   N_TI_WL, err);
<------><------>return err;
<------>}
<------>pr_debug("registered n_shared line discipline");
 
<------>st_gdata = kzalloc(sizeof(struct st_data_s), GFP_KERNEL);
<------>if (!st_gdata) {
<------><------>pr_err("memory allocation failed");
<------><------>err = tty_unregister_ldisc(N_TI_WL);
<------><------>if (err)
<------><------><------>pr_err("unable to un-register ldisc %ld", err);
<------><------>err = -ENOMEM;
<------><------>return err;
<------>}
 
<------>/* Initialize ST TxQ and Tx waitQ queue head. All BT/FM/GPS module skb's
<------> * will be pushed in this queue for actual transmission.
<------> */
<------>skb_queue_head_init(&st_gdata->txq);
<------>skb_queue_head_init(&st_gdata->tx_waitq);
 
<------>/* Locking used in st_int_enqueue() to avoid multiple execution */
<------>spin_lock_init(&st_gdata->lock);
 
<------>err = st_ll_init(st_gdata);
<------>if (err) {
<------><------>pr_err("error during st_ll initialization(%ld)", err);
<------><------>kfree(st_gdata);
<------><------>err = tty_unregister_ldisc(N_TI_WL);
<------><------>if (err)
<------><------><------>pr_err("unable to un-register ldisc");
<------><------>return err;
<------>}
 
<------>INIT_WORK(&st_gdata->work_write_wakeup, work_fn_write_wakeup);
 
<------>*core_data = st_gdata;
<------>return 0;
}
 
void st_core_exit(struct st_data_s *st_gdata)
{
<------>long err;
<------>/* internal module cleanup */
<------>err = st_ll_deinit(st_gdata);
<------>if (err)
<------><------>pr_err("error during deinit of ST LL %ld", err);
 
<------>if (st_gdata != NULL) {
<------><------>/* Free ST Tx Qs and skbs */
<------><------>skb_queue_purge(&st_gdata->txq);
<------><------>skb_queue_purge(&st_gdata->tx_waitq);
<------><------>kfree_skb(st_gdata->rx_skb);
<------><------>kfree_skb(st_gdata->tx_skb);
<------><------>/* TTY ldisc cleanup */
<------><------>err = tty_unregister_ldisc(N_TI_WL);
<------><------>if (err)
<------><------><------>pr_err("unable to un-register ldisc %ld", err);
<------><------>/* free the global data pointer */
<------><------>kfree(st_gdata);
<------>}
}