by Pavan Savoy

[permalink] [raw]

Subject: Re: [PATCH] drivers:staging: sources for ST core

Alan,

I have removed the global reference. Please suggest about the other 2 items,
1. having device contexts.
All of the data now is held in the tty device context.
What I couldn't do was when a particular protocol registers, like say BT driver registers with this driver via st_register, I couldn't pass the device context. even If I did like the hci device context in that case,
what use do I make of it ?

2. locking ?
What should be done about locking ?

---
drivers/staging/ti-st/st_core.c | 1058 +++++++++++++++++++++++++++++++++++++++
drivers/staging/ti-st/st_core.h | 98 ++++
2 files changed, 1156 insertions(+), 0 deletions(-)
create mode 100644 drivers/staging/ti-st/st_core.c
create mode 100644 drivers/staging/ti-st/st_core.h

diff --git a/drivers/staging/ti-st/st_core.c b/drivers/staging/ti-st/st_core.c
new file mode 100644
index 0000000..cb965b3
--- /dev/null
+++ b/drivers/staging/ti-st/st_core.c
@@ -0,0 +1,1058 @@
+/*
+ * Shared Transport Line discipline driver Core
+ * This hooks up ST KIM driver and ST LL driver
+ * Copyright (C) 2009 Texas Instruments
+ *
+ * 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/init.h>
+#include <linux/tty.h>
+
+/* understand BT, FM and GPS for now */
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/hci.h>
+#include "fm.h"
+/*
+ * packet formats for fm and gps
+ * #include "gps.h"
+ */
+#include "st_core.h"
+#include "st_kim.h"
+#include "st_ll.h"
+#include "st.h"
+
+#ifdef DEBUG
+/* strings to be used for rfkill entries and by
+ * ST Core to be used for sysfs debug entry
+ */
+#define PROTO_ENTRY(type, name) name
+const unsigned char *protocol_strngs[] = {
+ PROTO_ENTRY(ST_BT, "Bluetooth"),
+ PROTO_ENTRY(ST_FM, "FM"),
+ PROTO_ENTRY(ST_GPS, "GPS"),
+};
+#endif
+
+/********************************************************************/
+#if 0
+/* internal misc functions */
+bool is_protocol_list_empty(void)
+{
+ unsigned char i = 0;
+ pr_info(" %s ", __func__);
+ for (i = 0; i < ST_MAX; i++) {
+ if (st_gdata->list[i] != NULL)
+ return ST_NOTEMPTY;
+ /* not empty */
+ }
+ /* list empty */
+ return ST_EMPTY;
+}
+#endif
+/* 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)
+{
+#ifdef VERBOSE /* for debug */
+ int i;
+#endif
+ struct tty_struct *tty;
+ if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) {
+ pr_err("tty unavailable to perform write");
+ return ST_ERR_FAILURE;
+ }
+ tty = st_gdata->tty;
+#ifdef VERBOSE
+ printk(KERN_ERR "start data..\n");
+ for (i = 0; i < count; i++) /* no newlines for each datum */
+ printk(" %x", data[i]);
+ printk(KERN_ERR "\n ..end data\n");
+#endif
+ return tty->ops->write(tty, data, count);
+
+}
+
+/*
+ * push the skb received to relevant
+ * protocol stacks
+ */
+void st_send_frame(enum proto_type protoid, struct st_data_s *st_gdata)
+{
+ pr_info(" %s(prot:%d) ", __func__, protoid);
+
+ if (unlikely
+ (st_gdata == NULL || st_gdata->rx_skb == NULL
+ || st_gdata->list[protoid] == NULL)) {
+ pr_err("protocol %d not registered, no data to send?",
+ protoid);
+ 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[protoid]->recv != NULL)) {
+ if (unlikely(st_gdata->list[protoid]->recv(st_gdata->rx_skb)
+ != ST_SUCCESS)) {
+ pr_err(" proto stack %d's ->recv failed", protoid);
+ kfree_skb(st_gdata->rx_skb);
+ return;
+ }
+ } else {
+ pr_err(" proto stack %d's ->recv null", protoid);
+ kfree_skb(st_gdata->rx_skb);
+ }
+ pr_info(" done %s", __func__);
+ return;
+}
+
+/*
+ * to call registration complete callbacks
+ * of all protocol stack drivers
+ */
+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; i++) {
+ if (likely(st_gdata != NULL && st_gdata->list[i] != NULL &&
+ st_gdata->list[i]->reg_complete_cb != NULL))
+ st_gdata->list[i]->reg_complete_cb(err);
+ }
+}
+
+static inline int st_check_data_len(struct st_data_s *st_gdata,
+ int protoid, int len)
+{
+ register int room = skb_tailroom(st_gdata->rx_skb);
+
+ pr_info("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(protoid, 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_BT_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;
+
+ return 0;
+}
+
+/* internal function for action when wake-up ack
+ * received
+ */
+static inline void st_wakeup_ack(struct st_data_s *st_gdata,
+ unsigned char cmd)
+{
+ register 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);
+}
+
+/* Decodes received RAW data and forwards to corresponding
+ * client drivers (Bluetooth,FM,GPS..etc).
+ *
+ */
+void st_int_recv(void *disc_data,
+ const unsigned char *data, long count)
+{
+ register char *ptr;
+ struct hci_event_hdr *eh;
+ struct hci_acl_hdr *ah;
+ struct hci_sco_hdr *sh;
+ struct fm_event_hdr *fm;
+ struct gps_event_hdr *gps;
+ register int len = 0, type = 0, dlen = 0;
+ static enum proto_type protoid = ST_MAX;
+ struct st_data_s *st_gdata = (struct st_data_s *)disc_data;
+
+ ptr = (char *)data;
+ /* tty_receive sent null ? */
+ if (unlikely(ptr == NULL) || (st_gdata == NULL)) {
+ pr_err(" received null from TTY ");
+ return;
+ }
+
+ pr_info("count %ld rx_state %ld"
+ "rx_count %ld", count, st_gdata->rx_state,
+ st_gdata->rx_count);
+
+ /* 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_BT_W4_DATA:
+ pr_info("Complete pkt received");
+
+ /* Ask ST CORE to forward
+ * the packet to protocol driver */
+ st_send_frame(protoid, st_gdata);
+
+ st_gdata->rx_state = ST_W4_PACKET_TYPE;
+ st_gdata->rx_skb = NULL;
+ protoid = ST_MAX; /* is this required ? */
+ continue;
+
+ /* Waiting for Bluetooth event header ? */
+ case ST_BT_W4_EVENT_HDR:
+ eh = (struct hci_event_hdr *)st_gdata->rx_skb->
+ data;
+
+ pr_info("Event header: evt 0x%2.2x"
+ "plen %d", eh->evt, eh->plen);
+
+ st_check_data_len(st_gdata, protoid, eh->plen);
+ continue;
+
+ /* Waiting for Bluetooth acl header ? */
+ case ST_BT_W4_ACL_HDR:
+ ah = (struct hci_acl_hdr *)st_gdata->rx_skb->
+ data;
+ dlen = __le16_to_cpu(ah->dlen);
+
+ pr_info("ACL header: dlen %d", dlen);
+
+ st_check_data_len(st_gdata, protoid, dlen);
+ continue;
+
+ /* Waiting for Bluetooth sco header ? */
+ case ST_BT_W4_SCO_HDR:
+ sh = (struct hci_sco_hdr *)st_gdata->rx_skb->
+ data;
+
+ pr_info("SCO header: dlen %d", sh->dlen);
+
+ st_check_data_len(st_gdata, protoid, sh->dlen);
+ continue;
+ case ST_FM_W4_EVENT_HDR:
+ fm = (struct fm_event_hdr *)st_gdata->rx_skb->
+ data;
+ pr_info("FM Header: ");
+ st_check_data_len(st_gdata, ST_FM, fm->plen);
+ continue;
+ /* TODO : Add GPS packet machine logic here */
+ case ST_GPS_W4_EVENT_HDR:
+ /* [0x09 pkt hdr][R/W byte][2 byte len] */
+ gps = (struct gps_event_hdr *)st_gdata->rx_skb->
+ data;
+ pr_info("GPS Header: ");
+ st_check_data_len(st_gdata, ST_GPS, gps->plen);
+ 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) {
+
+ /* Bluetooth event packet? */
+ case HCI_EVENT_PKT:
+ pr_info("Event packet");
+ st_gdata->rx_state = ST_BT_W4_EVENT_HDR;
+ st_gdata->rx_count = HCI_EVENT_HDR_SIZE;
+ type = HCI_EVENT_PKT;
+ protoid = ST_BT;
+ break;
+
+ /* Bluetooth acl packet? */
+ case HCI_ACLDATA_PKT:
+ pr_info("ACL packet");
+ st_gdata->rx_state = ST_BT_W4_ACL_HDR;
+ st_gdata->rx_count = HCI_ACL_HDR_SIZE;
+ type = HCI_ACLDATA_PKT;
+ protoid = ST_BT;
+ break;
+
+ /* Bluetooth sco packet? */
+ case HCI_SCODATA_PKT:
+ pr_info("SCO packet");
+ st_gdata->rx_state = ST_BT_W4_SCO_HDR;
+ st_gdata->rx_count = HCI_SCO_HDR_SIZE;
+ type = HCI_SCODATA_PKT;
+ protoid = ST_BT;
+ break;
+
+ /* Channel 8(FM) packet? */
+ case ST_FM_CH8_PKT:
+ pr_info("FM CH8 packet");
+ type = ST_FM_CH8_PKT;
+ st_gdata->rx_state = ST_FM_W4_EVENT_HDR;
+ st_gdata->rx_count = FM_EVENT_HDR_SIZE;
+ protoid = ST_FM;
+ break;
+
+ /* Channel 9(GPS) packet? */
+ case 0x9: /*ST_LL_GPS_CH9_PKT */
+ pr_info("GPS CH9 packet");
+ type = 0x9; /* ST_LL_GPS_CH9_PKT; */
+ protoid = ST_GPS;
+ st_gdata->rx_state = ST_GPS_W4_EVENT_HDR;
+ st_gdata->rx_count = 3; /* GPS_EVENT_HDR_SIZE -1*/
+ break;
+ case LL_SLEEP_IND:
+ case LL_SLEEP_ACK:
+ case LL_WAKE_UP_IND:
+ pr_info("PM packet");
+ /* this takes appropriate action based on
+ * sleep state received --
+ */
+ st_ll_sleep_state(st_gdata, *ptr);
+ ptr++;
+ count--;
+ continue;
+ case LL_WAKE_UP_ACK:
+ pr_info("PM packet");
+ /* wake up ack received */
+ st_wakeup_ack(st_gdata, *ptr);
+ ptr++;
+ count--;
+ continue;
+ /* Unknow packet? */
+ default:
+ pr_err("Unknown packet type %2.2x", (__u8) *ptr);
+ ptr++;
+ count--;
+ continue;
+ };
+ ptr++;
+ count--;
+
+ switch (protoid) {
+ case ST_BT:
+ /* Allocate new packet to hold received data */
+ st_gdata->rx_skb =
+ bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC);
+ if (!st_gdata->rx_skb) {
+ pr_err("Can't allocate mem for new packet");
+ st_gdata->rx_state = ST_W4_PACKET_TYPE;
+ st_gdata->rx_count = 0;
+ return;
+ }
+ bt_cb(st_gdata->rx_skb)->pkt_type = type;
+ break;
+ case ST_FM: /* for FM */
+ st_gdata->rx_skb =
+ alloc_skb(FM_MAX_FRAME_SIZE, GFP_ATOMIC);
+ if (!st_gdata->rx_skb) {
+ pr_err("Can't allocate mem for new packet");
+ st_gdata->rx_state = ST_W4_PACKET_TYPE;
+ st_gdata->rx_count = 0;
+ return;
+ }
+ /* place holder 0x08 */
+ skb_reserve(st_gdata->rx_skb, 1);
+ st_gdata->rx_skb->cb[0] = ST_FM_CH8_PKT;
+ break;
+ case ST_GPS:
+ /* for GPS */
+ st_gdata->rx_skb =
+ alloc_skb(100 /*GPS_MAX_FRAME_SIZE */ , GFP_ATOMIC);
+ if (!st_gdata->rx_skb) {
+ pr_err("Can't allocate mem for new packet");
+ st_gdata->rx_state = ST_W4_PACKET_TYPE;
+ st_gdata->rx_count = 0;
+ return;
+ }
+ /* place holder 0x09 */
+ skb_reserve(st_gdata->rx_skb, 1);
+ st_gdata->rx_skb->cb[0] = 0x09; /*ST_GPS_CH9_PKT; */
+ break;
+ case ST_MAX:
+ break;
+ }
+ }
+ pr_info("done %s", __func__);
+ return;
+}
+
+/* internal de-Q function
+ * -- return previous in-completely written skb
+ * or return the skb in the txQ
+ */
+struct sk_buff *st_int_dequeue(struct st_data_s *st_gdata)
+{
+ struct sk_buff *returning_skb;
+
+ pr_info("%s", __func__);
+ /* if the previous skb wasn't written completely
+ */
+ if (st_gdata->tx_skb != NULL) {
+ returning_skb = st_gdata->tx_skb;
+ st_gdata->tx_skb = NULL;
+ return returning_skb;
+ }
+
+ /* de-Q from the txQ always if previous write is complete */
+ return skb_dequeue(&st_gdata->txq);
+}
+
+/* internal Q-ing function
+ * will either Q the skb to txq or the tx_waitq
+ * depending on the ST LL state
+ *
+ * lock the whole func - since ll_getstate and Q-ing should happen
+ * in one-shot
+ */
+void st_int_enqueue(struct st_data_s *st_gdata, struct sk_buff *skb)
+{
+ unsigned long flags = 0;
+
+ pr_info("%s", __func__);
+ /* this function can be invoked in more then one context.
+ * so have a lock */
+ spin_lock_irqsave(&st_gdata->lock, flags);
+
+ switch (st_ll_getstate(st_gdata)) {
+ case ST_LL_AWAKE:
+ pr_info("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: /* host cannot be in this state */
+ pr_err("ST LL is illegal state(%ld),"
+ "purging received skb.", st_ll_getstate(st_gdata));
+ kfree_skb(skb);
+ break;
+
+ case ST_LL_ASLEEP:
+ /* call a function of ST LL to put data
+ * in tx_waitQ and wake_ind in txQ
+ */
+ 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_info("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_info("%s", __func__);
+ /* check for sending & set flag sending here */
+ if (test_and_set_bit(ST_TX_SENDING, &st_data->tx_state)) {
+ pr_info("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, char *buf)
+{
+ unsigned long flags = 0;
+#ifdef DEBUG
+ unsigned char i = ST_MAX;
+#endif
+ spin_lock_irqsave(&st_gdata->lock, flags);
+#ifdef DEBUG /* more detailed log */
+ for (i = 0; i < ST_MAX; i++) {
+ if (i == 0) {
+ sprintf(buf, "%s is %s", protocol_strngs[i],
+ st_gdata->list[i] !=
+ NULL ? "Registered" : "Unregistered");
+ } else {
+ sprintf(buf, "%s\n%s is %s", buf, protocol_strngs[i],
+ st_gdata->list[i] !=
+ NULL ? "Registered" : "Unregistered");
+ }
+ }
+ sprintf(buf, "%s\n", buf);
+#else /* limited info */
+ sprintf(buf, "BT=%c\nFM=%c\nGPS=%c\n",
+ st_gdata->list[ST_BT] != NULL ? 'R' : 'U',
+ st_gdata->list[ST_FM] != NULL ? 'R' : 'U',
+ st_gdata->list[ST_GPS] != NULL ? 'R' : 'U');
+#endif
+ spin_unlock_irqrestore(&st_gdata->lock, flags);
+}
+
+/********************************************************************/
+/*
+ * 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 = ST_SUCCESS;
+ unsigned long flags = 0;
+
+ st_kim_ref(&st_gdata);
+ pr_info("%s(%d) ", __func__, new_proto->type);
+ 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 ST_ERR_FAILURE;
+ }
+
+ if (new_proto->type < ST_BT || new_proto->type >= ST_MAX) {
+ pr_err("protocol %d not supported", new_proto->type);
+ return ST_ERR_NOPROTO;
+ }
+
+ if (st_gdata->list[new_proto->type] != NULL) {
+ pr_err("protocol %d already registered", new_proto->type);
+ return ST_ERR_ALREADY;
+ }
+
+ /* 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->type);
+ /* fw download in progress */
+ st_kim_chip_toggle(new_proto->type, KIM_GPIO_ACTIVE);
+
+ st_gdata->list[new_proto->type] = new_proto;
+ new_proto->write = st_write;
+
+ set_bit(ST_REG_PENDING, &st_gdata->st_state);
+ spin_unlock_irqrestore(&st_gdata->lock, flags);
+ return ST_ERR_PENDING;
+ } else if (st_gdata->protos_registered == ST_EMPTY) {
+ pr_info(" protocol list empty :%d ", new_proto->type);
+ set_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state);
+
+ /* release lock previously held - re-locked below */
+ spin_unlock_irqrestore(&st_gdata->lock, flags);
+
+ /* enable the ST LL - to set default chip state */
+ st_ll_enable(st_gdata);
+ /* this may take a while to complete
+ * since it involves BT fw download
+ */
+ err = st_kim_start();
+ if (err != ST_SUCCESS) {
+ 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 ");
+ st_reg_complete(st_gdata, ST_ERR_FAILURE);
+ }
+
+ return ST_ERR_FAILURE;
+ }
+
+ /* the protocol might require other gpios to be toggled
+ */
+ st_kim_chip_toggle(new_proto->type, KIM_GPIO_ACTIVE);
+ clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state);
+
+ /* 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_info(" call reg complete callback ");
+ st_gdata->protos_registered++;
+ st_reg_complete(st_gdata, ST_SUCCESS);
+ }
+ clear_bit(ST_REG_PENDING, &st_gdata->st_state);
+
+ /* check for already registered once more,
+ * since the above check is old
+ */
+ if (st_gdata->list[new_proto->type] != NULL) {
+ pr_err(" proto %d already registered ",
+ new_proto->type);
+ return ST_ERR_ALREADY;
+ }
+
+ spin_lock_irqsave(&st_gdata->lock, flags);
+ st_gdata->list[new_proto->type] = new_proto;
+ new_proto->write = st_write;
+ spin_unlock_irqrestore(&st_gdata->lock, flags);
+ return err;
+ }
+ /* if fw is already downloaded & new stack registers protocol */
+ else {
+ switch (new_proto->type) {
+ case ST_BT:
+ /* do nothing */
+ break;
+ case ST_FM:
+ case ST_GPS:
+ st_kim_chip_toggle(new_proto->type, KIM_GPIO_ACTIVE);
+ break;
+ case ST_MAX:
+ default:
+ pr_err("%d protocol not supported",
+ new_proto->type);
+ err = ST_ERR_NOPROTO;
+ /* something wrong */
+ break;
+ }
+ st_gdata->list[new_proto->type] = new_proto;
+ new_proto->write = st_write;
+
+ /* lock already held before entering else */
+ spin_unlock_irqrestore(&st_gdata->lock, flags);
+ return err;
+ }
+ pr_info("done %s(%d) ", __func__, new_proto->type);
+}
+EXPORT_SYMBOL_GPL(st_register);
+
+/* to unregister a protocol -
+ * to be called from protocol stack driver
+ */
+long st_unregister(enum proto_type type)
+{
+ long err = ST_SUCCESS;
+ unsigned long flags = 0;
+ struct st_data_s *st_gdata;
+
+ pr_info("%s: %d ", __func__, type);
+
+ st_kim_ref(&st_gdata);
+ if (type < ST_BT || type >= ST_MAX) {
+ pr_err(" protocol %d not supported", type);
+ return ST_ERR_NOPROTO;
+ }
+
+ spin_lock_irqsave(&st_gdata->lock, flags);
+
+ if (st_gdata->list[type] == NULL) {
+ pr_err(" protocol %d not registered", type);
+ spin_unlock_irqrestore(&st_gdata->lock, flags);
+ return ST_ERR_NOPROTO;
+ }
+
+ st_gdata->protos_registered--;
+ st_gdata->list[type] = NULL;
+
+ /* kim ignores BT in the below function
+ * and handles the rest, BT is toggled
+ * only in kim_start and kim_stop
+ */
+ st_kim_chip_toggle(type, KIM_GPIO_INACTIVE);
+ 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 protocols unregistered ");
+
+ /* stop traffic on tty */
+ if (st_gdata->tty) {
+ tty_ldisc_flush(st_gdata->tty);
+ stop_tty(st_gdata->tty);
+ }
+
+ /* all protocols now unregistered */
+ st_kim_stop();
+ /* 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;
+#ifdef DEBUG
+ enum proto_type protoid = ST_MAX;
+#endif
+ long len;
+
+ st_kim_ref(&st_gdata);
+ if (unlikely(skb == NULL || st_gdata == NULL
+ || st_gdata->tty == NULL)) {
+ pr_err("data/tty unavailable to perform write");
+ return ST_ERR_FAILURE;
+ }
+#ifdef DEBUG /* open-up skb to read the 1st byte */
+ switch (skb->data[0]) {
+ case HCI_COMMAND_PKT:
+ case HCI_ACLDATA_PKT:
+ case HCI_SCODATA_PKT:
+ protoid = ST_BT;
+ break;
+ case ST_FM_CH8_PKT:
+ protoid = ST_FM;
+ break;
+ case 0x09:
+ protoid = ST_GPS;
+ break;
+ }
+ if (unlikely(st_gdata->list[protoid] == NULL)) {
+ pr_err(" protocol %d not registered, and writing? ",
+ protoid);
+ return ST_ERR_FAILURE;
+ }
+#endif
+ pr_info("%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 = ST_SUCCESS;
+ struct st_data_s *st_gdata;
+ pr_info("%s ", __func__);
+
+ st_kim_ref(&st_gdata);
+ 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();
+ pr_info("done %s", __func__);
+ return err;
+}
+
+static void st_tty_close(struct tty_struct *tty)
+{
+ unsigned char i = ST_MAX;
+ 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; i++) {
+ if (st_gdata->list[i] != NULL)
+ pr_err("%d not un-registered", i);
+ st_gdata->list[i] = NULL;
+ }
+ 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->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_info("%s: done ", __func__);
+}
+
+static void st_tty_receive(struct tty_struct *tty, const unsigned char *data,
+ char *tty_flags, int count)
+{
+ struct st_data_s *st_gdata = tty->disc_data;
+#ifdef VERBOSE
+ long i;
+ printk(KERN_ERR "incoming data...\n");
+ for (i = 0; i < count; i++)
+ printk(" %x", data[i]);
+ printk(KERN_ERR "\n.. data end\n");
+#endif
+
+ if (test_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state)) {
+ /*
+ * if fw download is in progress then route incoming data
+ * to KIM for validation
+ */
+ st_kim_recv(st_gdata, data, count);
+ } else {
+ st_int_recv(st_gdata, data, count);
+ }
+ pr_info("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_info("%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_info("%s ", __func__);
+
+ kfree_skb(st_gdata->tx_skb);
+ st_gdata->tx_skb = NULL;
+
+ tty->ops->flush_buffer(tty);
+ return;
+}
+
+/********************************************************************/
+int st_core_init(struct st_data_s **core_data)
+{
+ struct st_data_s *st_gdata;
+ long err;
+ static struct tty_ldisc_ops *st_ldisc_ops;
+
+ /* populate and register to TTY line discipline */
+ st_ldisc_ops = kzalloc(sizeof(*st_ldisc_ops), GFP_KERNEL);
+ if (!st_ldisc_ops) {
+ pr_err("no mem to allocate");
+ return -ENOMEM;
+ }
+
+ st_ldisc_ops->magic = TTY_LDISC_MAGIC;
+ st_ldisc_ops->name = "n_st"; /*"n_hci"; */
+ st_ldisc_ops->open = st_tty_open;
+ st_ldisc_ops->close = st_tty_close;
+ st_ldisc_ops->receive_buf = st_tty_receive;
+ st_ldisc_ops->write_wakeup = st_tty_wakeup;
+ st_ldisc_ops->flush_buffer = st_tty_flush_buffer;
+ st_ldisc_ops->owner = THIS_MODULE;
+
+ err = tty_register_ldisc(N_TI_WL, st_ldisc_ops);
+ if (err) {
+ pr_err("error registering %d line discipline %ld",
+ N_TI_WL, err);
+ kfree(st_ldisc_ops);
+ return err;
+ }
+ pr_info("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);
+ kfree(st_ldisc_ops);
+ 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);
+
+ /* ldisc_ops ref to be only used in __exit of module */
+ st_gdata->ldisc_ops = st_ldisc_ops;
+
+#if 0
+ err = st_kim_init();
+ if (err) {
+ pr_err("error during kim initialization(%ld)", err);
+ kfree(st_gdata);
+ err = tty_unregister_ldisc(N_TI_WL);
+ if (err)
+ pr_err("unable to un-register ldisc");
+ kfree(st_ldisc_ops);
+ return -1;
+ }
+#endif
+
+ 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");
+ kfree(st_ldisc_ops);
+ return -1;
+ }
+ *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 0
+ err = st_kim_deinit();
+ if (err)
+ pr_err("error during deinit of ST KIM %ld", err);
+#endif
+ 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);
+ kfree(st_gdata->ldisc_ops);
+ /* free the global data pointer */
+ kfree(st_gdata);
+ }
+}
+
+
diff --git a/drivers/staging/ti-st/st_core.h b/drivers/staging/ti-st/st_core.h
new file mode 100644
index 0000000..f271c88
--- /dev/null
+++ b/drivers/staging/ti-st/st_core.h
@@ -0,0 +1,98 @@
+/*
+ * Shared Transport Core header file
+ *
+ * Copyright (C) 2009 Texas Instruments
+ *
+ * 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
+ *
+ */
+
+#ifndef ST_CORE_H
+#define ST_CORE_H
+
+#include <linux/skbuff.h>
+#include "st.h"
+
+/* states of protocol list */
+#define ST_NOTEMPTY 1
+#define ST_EMPTY 0
+
+/*
+ * possible st_states
+ */
+#define ST_INITIALIZING 1
+#define ST_REG_IN_PROGRESS 2
+#define ST_REG_PENDING 3
+#define ST_WAITING_FOR_RESP 4
+
+/*
+ * local data required for ST/KIM/ST-HCI-LL
+ */
+struct st_data_s {
+ unsigned long st_state;
+/*
+ * an instance of tty_struct & ldisc ops to move around
+ */
+ struct tty_struct *tty;
+ struct tty_ldisc_ops *ldisc_ops;
+/*
+ * the tx skb -
+ * if the skb is already dequeued and the tty failed to write the same
+ * maintain the skb to write in the next transaction
+ */
+ struct sk_buff *tx_skb;
+#define ST_TX_SENDING 1
+#define ST_TX_WAKEUP 2
+ unsigned long tx_state;
+/*
+ * list of protocol registered
+ */
+ struct st_proto_s *list[ST_MAX];
+/*
+ * lock
+ */
+ unsigned long rx_state;
+ unsigned long rx_count;
+ struct sk_buff *rx_skb;
+ struct sk_buff_head txq, tx_waitq;
+ spinlock_t lock; /* ST LL state lock */
+ unsigned char protos_registered;
+ unsigned long ll_state; /* ST LL power state */
+};
+
+/* point this to tty->driver->write or tty->ops->write
+ * depending upon the kernel version
+ */
+int st_int_write(struct st_data_s*, const unsigned char*, int);
+/* internal write function, passed onto protocol drivers
+ * via the write function ptr of protocol struct
+ */
+long st_write(struct sk_buff *);
+/* function to be called from ST-LL
+ */
+void st_ll_send_frame(enum proto_type, struct sk_buff *);
+/* internal wake up function */
+void st_tx_wakeup(struct st_data_s *st_data);
+
+int st_core_init(struct st_data_s **);
+void st_core_exit(struct st_data_s *);
+void st_kim_ref(struct st_data_s **);
+
+#define GPS_STUB_TEST
+#ifdef GPS_STUB_TEST
+int gps_chrdrv_stub_write(const unsigned char*, int);
+void gps_chrdrv_stub_init(void);
+#endif
+
+#endif /*ST_CORE_H */
--
1.5.4.3