--- /dev/null
+/*
+ * 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>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#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, char 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);
+ memcpy(skb_put(st_gdata->rx_skb, len), 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)
+ */
+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;
+ }
+ pr_debug("done %s(%d) ", __func__, new_proto->chnl_id);
+}
+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)
+{
+ int err = 0;
+ 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 err;
+}
+
+static void st_tty_close(struct tty_struct *tty)
+{
+ unsigned char i = ST_MAX_CHANNELS;
+ unsigned long flags = 0;
+ 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);
+
+ /* call our internal wakeup */
+ st_tx_wakeup((void *)st_gdata);
+}
+
+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;
+ }
+ *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);
+ }
+}
Code Review / kvmfornfv.git / blobdiff