/*
* Texas Instrument's Bluetooth Driver For Shared Transport.
*
* Bluetooth Driver acts as interface between HCI core and
* TI Shared Transport Layer.
*
* Copyright (C) 2009-2010 Texas Instruments
* Author: Raja Mani <raja_mani@ti.com>
* 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 DEBUG
#include <linux/platform_device.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/hci.h>
#include <linux/ti_wilink_st.h>
#include <linux/module.h>
/* Bluetooth Driver Version */
#define VERSION "1.0"
#define MAX_BT_CHNL_IDS 3
/* Number of seconds to wait for registration completion
* when ST returns PENDING status.
*/
#define BT_REGISTER_TIMEOUT 6000 /* 6 sec */
/**
* struct ti_st - driver operation structure
* @hdev: hci device pointer which binds to bt driver
* @reg_status: ST registration callback status
* @st_write: write function provided by the ST driver
* to be used by the driver during send_frame.
* @wait_reg_completion - completion sync between ti_st_open
* and st_reg_completion_cb.
*/
struct ti_st {
struct hci_dev *hdev;
char reg_status;
long (*st_write) (struct sk_buff *);
struct completion wait_reg_completion;
};
/* Increments HCI counters based on pocket ID (cmd,acl,sco) */
static inline void ti_st_tx_complete(struct ti_st *hst, int pkt_type)
{
struct hci_dev *hdev = hst->hdev;
/* Update HCI stat counters */
switch (pkt_type) {
case HCI_COMMAND_PKT:
hdev->stat.cmd_tx++;
break;
case HCI_ACLDATA_PKT:
hdev->stat.acl_tx++;
break;
case HCI_SCODATA_PKT:
hdev->stat.sco_tx++;
break;
}
}
/* ------- Interfaces to Shared Transport ------ */
/* Called by ST layer to indicate protocol registration completion
* status.ti_st_open() function will wait for signal from this
* API when st_register() function returns ST_PENDING.
*/
static void st_reg_completion_cb(void *priv_data, char data)
{
struct ti_st *lhst = priv_data;
/* Save registration status for use in ti_st_open() */
lhst->reg_status = data;
/* complete the wait in ti_st_open() */
complete(&lhst->wait_reg_completion);
}
/* Called by Shared Transport layer when receive data is
* available */
static long st_receive(void *priv_data, struct sk_buff *skb)
{
struct ti_st *lhst = priv_data;
int err;
if (!skb)
return -EFAULT;
if (!lhst) {
kfree_skb(skb);
return -EFAULT;
}
skb->dev = (void *) lhst->hdev;
/* Forward skb to HCI core layer */
err = hci_recv_frame(skb);
if (err < 0) {
BT_ERR("Unable to push skb to HCI core(%d)", err);
return err;
}
lhst->hdev->stat.byte_rx += skb->len;
return 0;
}
/* ------- Interfaces to HCI layer ------ */
/* protocol structure registered with shared transport */
static struct st_proto_s ti_st_proto[MAX_BT_CHNL_IDS] = {
{
.chnl_id = HCI_EVENT_PKT, /* HCI Events */
.hdr_len = sizeof(struct hci_event_hdr),
.offset_len_in_hdr = offsetof(struct hci_event_hdr, plen),
.len_size = 1, /* sizeof(plen) in struct hci_event_hdr */
.reserve = 8,
},
{
.chnl_id = HCI_ACLDATA_PKT, /* ACL */
.hdr_len = sizeof(struct hci_acl_hdr),
.offset_len_in_hdr = offsetof(struct hci_acl_hdr, dlen),
.len_size = 2, /* sizeof(dlen) in struct hci_acl_hdr */
.reserve = 8,
},
{
.chnl_id = HCI_SCODATA_PKT, /* SCO */
.hdr_len = sizeof(struct hci_sco_hdr),
.offset_len_in_hdr = offsetof(struct hci_sco_hdr, dlen),
.len_size = 1, /* sizeof(dlen) in struct hci_sco_hdr */
.reserve = 8,
},
};
/* Called from HCI core to initialize the device */
static int ti_st_open(struct hci_dev *hdev)
{
unsigned long timeleft;
struct ti_st *hst;
int err, i;
BT_DBG("%s %p", hdev->name, hdev);
if (test_and_set_bit(HCI_RUNNING, &hdev->flags))
return -EBUSY;
/* provide contexts for callbacks from ST */
hst = hci_get_drvdata(hdev);
for (i = 0; i < MAX_BT_CHNL_IDS; i++) {
ti_st_proto[i].priv_data = hst;
ti_st_proto[i].max_frame_size = HCI_MAX_FRAME_SIZE;
ti_st_proto[i].recv = st_receive;
ti_st_proto[i].reg_complete_cb = st_reg_completion_cb;
/* Prepare wait-for-completion handler */
init_completion(&hst->wait_reg_completion);
/* Reset ST registration callback status flag,
* this value will be updated in
* st_reg_completion_cb()
* function whenever it called from ST driver.
*/
hst->reg_status = -EINPROGRESS;
err = st_register(&ti_st_proto[i]);
if (!err)
goto done;
if (err != -EINPROGRESS) {
clear_bit(HCI_RUNNING, &hdev->flags);
BT_ERR("st_register failed %d", err);
return err;
}
/* ST is busy with either protocol
* registration or firmware download.
*/
BT_DBG("waiting for registration "
"completion signal from ST");
timeleft = wait_for_completion_timeout
(&hst->wait_reg_completion,
msecs_to_jiffies(BT_REGISTER_TIMEOUT));
if (!timeleft) {
clear_bit(HCI_RUNNING, &hdev->flags);
BT_ERR("Timeout(%d sec),didn't get reg "
"completion signal from ST",
BT_REGISTER_TIMEOUT / 1000);
return -ETIMEDOUT;
}
/* Is ST registration callback
* called with ERROR status? */
if (hst->reg_status != 0) {
clear_bit(HCI_RUNNING, &hdev->flags);
BT_ERR("ST registration completed with invalid "
"status %d", hst->reg_status);
return -EAGAIN;
}
done:
hst->st_write = ti_st_proto[i].write;
if (!hst->st_write) {
BT_ERR("undefined ST write function");
clear_bit(HCI_RUNNING, &hdev->flags);
for (i = 0; i < MAX_BT_CHNL_IDS; i++) {
/* Undo registration with ST */
err = st_unregister(&ti_st_proto[i]);
if (err)
BT_ERR("st_unregister() failed with "
"error %d", err);
hst->st_write = NULL;
}
return -EIO;
}
}
return 0;
}
/* Close device */
static int ti_st_close(struct hci_dev *hdev)
{
int err, i;
struct ti_st *hst = hci_get_drvdata(hdev);
if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
return 0;
for (i = MAX_BT_CHNL_IDS-1; i >= 0; i--) {
err = st_unregister(&ti_st_proto[i]);
if (err)
BT_ERR("st_unregister(%d) failed with error %d",
ti_st_proto[i].chnl_id, err);
}
hst->st_write = NULL;
return err;
}
static int ti_st_send_frame(struct sk_buff *skb)
{
struct hci_dev *hdev;
struct ti_st *hst;
long len;
hdev = (struct hci_dev *)skb->dev;
if (!test_bit(HCI_RUNNING, &hdev->flags))
return -EBUSY;
hst = hci_get_drvdata(hdev);
/* Prepend skb with frame type */
memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type,
skb->len);
/* Insert skb to shared transport layer's transmit queue.
* Freeing skb memory is taken care in shared transport layer,
* so don't free skb memory here.
*/
len = hst->st_write(skb);
if (len < 0) {
kfree_skb(skb);
BT_ERR("ST write failed (%ld)", len);
/* Try Again, would only fail if UART has gone bad */
return -EAGAIN;
}
/* ST accepted our skb. So, Go ahead and do rest */
hdev->stat.byte_tx += len;
ti_st_tx_complete(hst, bt_cb(skb)->pkt_type);
return 0;
}
static int bt_ti_probe(struct platform_device *pdev)
{
static struct ti_st *hst;
struct hci_dev *hdev;
int err;
hst = devm_kzalloc(&pdev->dev, sizeof(struct ti_st), GFP_KERNEL);
if (!hst)
return -ENOMEM;
/* Expose "hciX" device to user space */
hdev = hci_alloc_dev();
if (!hdev)
return -ENOMEM;
BT_DBG("hdev %p", hdev);
hst->hdev = hdev;
hdev->bus = HCI_UART;
hci_set_drvdata(hdev, hst);
hdev->open = ti_st_open;
hdev->close = ti_st_close;
hdev->flush = NULL;
hdev->send = ti_st_send_frame;
err = hci_register_dev(hdev);
if (err < 0) {
BT_ERR("Can't register HCI device error %d", err);
hci_free_dev(hdev);
return err;
}
BT_DBG("HCI device registered (hdev %p)", hdev);
dev_set_drvdata(&pdev->dev, hst);
return err;
}
static int bt_ti_remove(struct platform_device *pdev)
{
struct hci_dev *hdev;
struct ti_st *hst = dev_get_drvdata(&pdev->dev);
if (!hst)
return -EFAULT;
BT_DBG("%s", hst->hdev->name);
hdev = hst->hdev;
ti_st_close(hdev);
hci_unregister_dev(hdev);
hci_free_dev(hdev);
dev_set_drvdata(&pdev->dev, NULL);
return 0;
}
static struct platform_driver btwilink_driver = {
.probe = bt_ti_probe,
.remove = bt_ti_remove,
.driver = {
.name = "btwilink",
.owner = THIS_MODULE,
},
};
module_platform_driver(btwilink_driver);
/* ------ Module Info ------ */
MODULE_AUTHOR("Raja Mani <raja_mani@ti.com>");
MODULE_DESCRIPTION("Bluetooth Driver for TI Shared Transport" VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
