blob: 101697f2d4e04da98c1b3e6eb8dadd84011bf34b [file] [log] [blame]
/*
* HCI_SMD (HCI Shared Memory Driver) is Qualcomm's Shared memory driver
* for the BT HCI protocol.
*
* Copyright (c) 2000-2001, 2011 Code Aurora Forum. All rights reserved.
* Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
* Copyright (C) 2004-2006 Marcel Holtmann <marcel@holtmann.org>
*
* This file is based on drivers/bluetooth/hci_vhci.c
*
* 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.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/skbuff.h>
#include <linux/wakelock.h>
#include <linux/uaccess.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/hci.h>
#include <mach/msm_smd.h>
#define EVENT_CHANNEL "APPS_RIVA_BT_CMD"
#define DATA_CHANNEL "APPS_RIVA_BT_ACL"
#define RX_Q_MONITOR (1) /* 1 milli second */
static int hcismd_set;
static DEFINE_MUTEX(hci_smd_enable);
static int hcismd_set_enable(const char *val, struct kernel_param *kp);
module_param_call(hcismd_set, hcismd_set_enable, NULL, &hcismd_set, 0644);
struct hci_smd_data {
struct hci_dev *hdev;
struct smd_channel *event_channel;
struct smd_channel *data_channel;
struct wake_lock wake_lock_tx;
struct wake_lock wake_lock_rx;
struct timer_list rx_q_timer;
struct tasklet_struct hci_event_task;
struct tasklet_struct hci_data_task;
};
static struct hci_smd_data hs;
/* Rx queue monitor timer function */
static int is_rx_q_empty(unsigned long arg)
{
struct hci_dev *hdev = (struct hci_dev *) arg;
struct sk_buff_head *list_ = &hdev->rx_q;
struct sk_buff *list = ((struct sk_buff *)list_)->next;
BT_DBG("%s Rx timer triggered", hdev->name);
if (list == (struct sk_buff *)list_) {
BT_DBG("%s RX queue empty", hdev->name);
return 1;
} else{
BT_DBG("%s RX queue not empty", hdev->name);
return 0;
}
}
static void release_lock(void)
{
struct hci_smd_data *hsmd = &hs;
BT_DBG("Releasing Rx Lock");
if (is_rx_q_empty((unsigned long)hsmd->hdev) &&
wake_lock_active(&hs.wake_lock_rx))
wake_unlock(&hs.wake_lock_rx);
}
/* Rx timer callback function */
static void schedule_timer(unsigned long arg)
{
struct hci_dev *hdev = (struct hci_dev *) arg;
struct hci_smd_data *hsmd = &hs;
BT_DBG("%s Schedule Rx timer", hdev->name);
if (is_rx_q_empty(arg) && wake_lock_active(&hs.wake_lock_rx)) {
BT_DBG("%s RX queue empty", hdev->name);
/*
* Since the queue is empty, its ideal
* to release the wake lock on Rx
*/
wake_unlock(&hs.wake_lock_rx);
} else{
BT_DBG("%s RX queue not empty", hdev->name);
/*
* Restart the timer to monitor whether the Rx queue is
* empty for releasing the Rx wake lock
*/
mod_timer(&hsmd->rx_q_timer,
jiffies + msecs_to_jiffies(RX_Q_MONITOR));
}
}
static int hci_smd_open(struct hci_dev *hdev)
{
set_bit(HCI_RUNNING, &hdev->flags);
return 0;
}
static int hci_smd_close(struct hci_dev *hdev)
{
if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
return 0;
else
return -EPERM;
}
static void hci_smd_destruct(struct hci_dev *hdev)
{
if (NULL != hdev->driver_data)
kfree(hdev->driver_data);
}
static void hci_smd_recv_data(unsigned long arg)
{
int len = 0;
int rc = 0;
struct sk_buff *skb = NULL;
unsigned char *buf = NULL;
struct hci_smd_data *hsmd = &hs;
wake_lock(&hs.wake_lock_rx);
len = smd_read_avail(hsmd->data_channel);
if (len > HCI_MAX_FRAME_SIZE) {
BT_ERR("Frame larger than the allowed size");
goto out_data;
}
while (len > 0) {
skb = bt_skb_alloc(len, GFP_ATOMIC);
if (!skb) {
BT_ERR("Error in allocating socket buffer");
goto out_data;
}
buf = kmalloc(len, GFP_ATOMIC);
if (!buf) {
BT_ERR("Error in allocating buffer");
rc = -ENOMEM;
goto out_data;
}
rc = smd_read(hsmd->data_channel, (void *)buf, len);
if (rc < len) {
BT_ERR("Error in reading from the channel");
goto out_data;
}
memcpy(skb_put(skb, len), buf, len);
skb->dev = (void *)hsmd->hdev;
bt_cb(skb)->pkt_type = HCI_ACLDATA_PKT;
skb_orphan(skb);
rc = hci_recv_frame(skb);
if (rc < 0) {
BT_ERR("Error in passing the packet to HCI Layer");
/*
* skb is getting freed in hci_recv_frame, making it
* to null to avoid multiple access
*/
skb = NULL;
goto out_data;
}
kfree(buf);
buf = NULL;
len = smd_read_avail(hsmd->data_channel);
/*
* Start the timer to monitor whether the Rx queue is
* empty for releasing the Rx wake lock
*/
BT_DBG("Rx Timer is starting");
mod_timer(&hsmd->rx_q_timer,
jiffies + msecs_to_jiffies(RX_Q_MONITOR));
}
out_data:
release_lock();
if (rc) {
if (skb)
kfree_skb(skb);
kfree(buf);
}
}
static void hci_smd_recv_event(unsigned long arg)
{
int len = 0;
int rc = 0;
struct sk_buff *skb = NULL;
unsigned char *buf = NULL;
struct hci_smd_data *hsmd = &hs;
wake_lock(&hs.wake_lock_rx);
len = smd_read_avail(hsmd->event_channel);
if (len > HCI_MAX_FRAME_SIZE) {
BT_ERR("Frame larger than the allowed size");
goto out_event;
}
while (len > 0) {
skb = bt_skb_alloc(len, GFP_ATOMIC);
if (!skb) {
BT_ERR("Error in allocating socket buffer");
goto out_event;
}
buf = kmalloc(len, GFP_ATOMIC);
if (!buf) {
BT_ERR("Error in allocating buffer");
rc = -ENOMEM;
goto out_event;
}
rc = smd_read(hsmd->event_channel, (void *)buf, len);
if (rc < len) {
BT_ERR("Error in reading from the event channel");
goto out_event;
}
memcpy(skb_put(skb, len), buf, len);
skb->dev = (void *)hsmd->hdev;
bt_cb(skb)->pkt_type = HCI_EVENT_PKT;
skb_orphan(skb);
rc = hci_recv_frame(skb);
if (rc < 0) {
BT_ERR("Error in passing the packet to HCI Layer");
/*
* skb is getting freed in hci_recv_frame, making it
* to null to avoid multiple access
*/
skb = NULL;
goto out_event;
}
kfree(buf);
buf = NULL;
len = smd_read_avail(hsmd->event_channel);
/*
* Start the timer to monitor whether the Rx queue is
* empty for releasing the Rx wake lock
*/
BT_DBG("Rx Timer is starting");
mod_timer(&hsmd->rx_q_timer,
jiffies + msecs_to_jiffies(RX_Q_MONITOR));
}
out_event:
release_lock();
if (rc) {
if (skb)
kfree_skb(skb);
kfree(buf);
}
}
static int hci_smd_send_frame(struct sk_buff *skb)
{
int len;
int avail;
int ret = 0;
wake_lock(&hs.wake_lock_tx);
switch (bt_cb(skb)->pkt_type) {
case HCI_COMMAND_PKT:
avail = smd_write_avail(hs.event_channel);
if (!avail) {
BT_ERR("No space available for smd frame");
ret = -ENOSPC;
}
len = smd_write(hs.event_channel, skb->data, skb->len);
if (len < skb->len) {
BT_ERR("Failed to write Command %d", len);
ret = -ENODEV;
}
break;
case HCI_ACLDATA_PKT:
case HCI_SCODATA_PKT:
avail = smd_write_avail(hs.data_channel);
if (!avail) {
BT_ERR("No space available for smd frame");
ret = -ENOSPC;
}
len = smd_write(hs.data_channel, skb->data, skb->len);
if (len < skb->len) {
BT_ERR("Failed to write Data %d", len);
ret = -ENODEV;
}
break;
default:
BT_ERR("Uknown packet type");
ret = -ENODEV;
break;
}
kfree_skb(skb);
wake_unlock(&hs.wake_lock_tx);
return ret;
}
static void hci_smd_notify_event(void *data, unsigned int event)
{
struct hci_dev *hdev = hs.hdev;
struct hci_smd_data *hsmd = &hs;
int len = 0;
if (!hdev) {
BT_ERR("Frame for unknown HCI device (hdev=NULL)");
return;
}
switch (event) {
case SMD_EVENT_DATA:
len = smd_read_avail(hsmd->event_channel);
if (len > 0)
tasklet_hi_schedule(&hs.hci_event_task);
else if (len < 0)
BT_ERR("Failed to read event from smd %d", len);
break;
case SMD_EVENT_OPEN:
BT_INFO("opening HCI-SMD channel :%s", EVENT_CHANNEL);
hci_smd_open(hdev);
break;
case SMD_EVENT_CLOSE:
BT_INFO("Closing HCI-SMD channel :%s", EVENT_CHANNEL);
hci_smd_close(hdev);
break;
default:
break;
}
}
static void hci_smd_notify_data(void *data, unsigned int event)
{
struct hci_dev *hdev = hs.hdev;
struct hci_smd_data *hsmd = &hs;
int len = 0;
if (!hdev) {
BT_ERR("HCI device (hdev=NULL)");
return;
}
switch (event) {
case SMD_EVENT_DATA:
len = smd_read_avail(hsmd->data_channel);
if (len > 0)
tasklet_hi_schedule(&hs.hci_data_task);
else if (len < 0)
BT_ERR("Failed to read data from smd %d", len);
break;
case SMD_EVENT_OPEN:
BT_INFO("opening HCI-SMD channel :%s", DATA_CHANNEL);
hci_smd_open(hdev);
break;
case SMD_EVENT_CLOSE:
BT_INFO("Closing HCI-SMD channel :%s", DATA_CHANNEL);
hci_smd_close(hdev);
break;
default:
break;
}
}
static int hci_smd_register_dev(struct hci_smd_data *hsmd)
{
static struct hci_dev *hdev;
int rc;
/* Initialize and register HCI device */
hdev = hci_alloc_dev();
if (!hdev) {
BT_ERR("Can't allocate HCI device");
return -ENOMEM;
}
hsmd->hdev = hdev;
hdev->bus = HCI_SMD;
hdev->driver_data = NULL;
hdev->open = hci_smd_open;
hdev->close = hci_smd_close;
hdev->send = hci_smd_send_frame;
hdev->destruct = hci_smd_destruct;
hdev->owner = THIS_MODULE;
tasklet_init(&hsmd->hci_event_task,
hci_smd_recv_event, (unsigned long) hsmd);
tasklet_init(&hsmd->hci_data_task,
hci_smd_recv_data, (unsigned long) hsmd);
/*
* Setup the timer to monitor whether the Rx queue is empty,
* to control the wake lock release
*/
setup_timer(&hsmd->rx_q_timer, schedule_timer,
(unsigned long) hsmd->hdev);
/* Open the SMD Channel and device and register the callback function */
rc = smd_named_open_on_edge(EVENT_CHANNEL, SMD_APPS_WCNSS,
&hsmd->event_channel, hdev, hci_smd_notify_event);
if (rc < 0) {
BT_ERR("Cannot open the command channel");
hci_free_dev(hdev);
hdev = NULL;
return -ENODEV;
}
rc = smd_named_open_on_edge(DATA_CHANNEL, SMD_APPS_WCNSS,
&hsmd->data_channel, hdev, hci_smd_notify_data);
if (rc < 0) {
BT_ERR("Failed to open the Data channel");
hci_free_dev(hdev);
hdev = NULL;
return -ENODEV;
}
/* Disable the read interrupts on the channel */
smd_disable_read_intr(hsmd->event_channel);
smd_disable_read_intr(hsmd->data_channel);
if (hci_register_dev(hdev) < 0) {
BT_ERR("Can't register HCI device");
hci_free_dev(hdev);
return -ENODEV;
}
return 0;
}
static void hci_smd_deregister_dev(struct hci_smd_data *hsmd)
{
if (hsmd->hdev) {
if (hci_unregister_dev(hsmd->hdev) < 0)
BT_ERR("Can't unregister HCI device %s",
hsmd->hdev->name);
hci_free_dev(hsmd->hdev);
hsmd->hdev = NULL;
}
smd_close(hs.event_channel);
smd_close(hs.data_channel);
if (wake_lock_active(&hs.wake_lock_rx))
wake_unlock(&hs.wake_lock_rx);
if (wake_lock_active(&hs.wake_lock_tx))
wake_unlock(&hs.wake_lock_tx);
/*Destroy the timer used to monitor the Rx queue for emptiness */
if (hs.rx_q_timer.function) {
del_timer_sync(&hs.rx_q_timer);
hs.rx_q_timer.function = NULL;
hs.rx_q_timer.data = 0;
}
tasklet_kill(&hs.hci_event_task);
tasklet_kill(&hs.hci_data_task);
}
static int hcismd_set_enable(const char *val, struct kernel_param *kp)
{
int ret = 0;
mutex_lock(&hci_smd_enable);
ret = param_set_int(val, kp);
if (ret)
goto done;
switch (hcismd_set) {
case 1:
hci_smd_register_dev(&hs);
break;
case 0:
hci_smd_deregister_dev(&hs);
break;
default:
ret = -EFAULT;
}
done:
mutex_unlock(&hci_smd_enable);
return ret;
}
static int __init hci_smd_init(void)
{
wake_lock_init(&hs.wake_lock_rx, WAKE_LOCK_SUSPEND,
"msm_smd_Rx");
wake_lock_init(&hs.wake_lock_tx, WAKE_LOCK_SUSPEND,
"msm_smd_Tx");
return 0;
}
module_init(hci_smd_init);
static void __exit hci_smd_exit(void)
{
wake_lock_destroy(&hs.wake_lock_rx);
wake_lock_destroy(&hs.wake_lock_tx);
}
module_exit(hci_smd_exit);
MODULE_AUTHOR("Ankur Nandwani <ankurn@codeaurora.org>");
MODULE_DESCRIPTION("Bluetooth SMD driver");
MODULE_LICENSE("GPL v2");