btuart_cs.c
/*
*
* Driver for Bluetooth PCMCIA cards with HCI UART interface
*
* Copyright (C) 2001-2002 Marcel Holtmann <marcel@holtmann.org>
*
*
* 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;
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The initial developer of the original code is David A. Hinds
* <dahinds@users.sourceforge.net>. Portions created by David A. Hinds
* are Copyright (C) 1999 David A. Hinds. All Rights Reserved.
*
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/spinlock.h>
#include <linux/moduleparam.h>
#include <linux/skbuff.h>
#include <linux/string.h>
#include <linux/serial.h>
#include <linux/serial_reg.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <pcmcia/cistpl.h>
#include <pcmcia/ciscode.h>
#include <pcmcia/ds.h>
#include <pcmcia/cisreg.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
/* ======================== Module parameters ======================== */
MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("Bluetooth driver for Bluetooth PCMCIA cards with HCI UART interface");
MODULE_LICENSE("GPL");
/* ======================== Local structures ======================== */
struct btuart_info {
struct pcmcia_device *p_dev;
struct hci_dev *hdev;
spinlock_t lock; /* For serializing operations */
struct sk_buff_head txq;
unsigned long tx_state;
unsigned long rx_state;
unsigned long rx_count;
struct sk_buff *rx_skb;
};
static int btuart_config(struct pcmcia_device *link);
static void btuart_release(struct pcmcia_device *link);
static void btuart_detach(struct pcmcia_device *p_dev);
/* Maximum baud rate */
#define SPEED_MAX 115200
/* Default baud rate: 57600, 115200, 230400 or 460800 */
#define DEFAULT_BAUD_RATE 115200
/* Transmit states */
#define XMIT_SENDING 1
#define XMIT_WAKEUP 2
#define XMIT_WAITING 8
/* Receiver states */
#define RECV_WAIT_PACKET_TYPE 0
#define RECV_WAIT_EVENT_HEADER 1
#define RECV_WAIT_ACL_HEADER 2
#define RECV_WAIT_SCO_HEADER 3
#define RECV_WAIT_DATA 4
/* ======================== Interrupt handling ======================== */
static int btuart_write(unsigned int iobase, int fifo_size, __u8 *buf, int len)
{
int actual = 0;
/* Tx FIFO should be empty */
if (!(inb(iobase + UART_LSR) & UART_LSR_THRE))
return 0;
/* Fill FIFO with current frame */
while ((fifo_size-- > 0) && (actual < len)) {
/* Transmit next byte */
outb(buf[actual], iobase + UART_TX);
actual++;
}
return actual;
}
static void btuart_write_wakeup(struct btuart_info *info)
{
if (!info) {
BT_ERR("Unknown device");
return;
}
if (test_and_set_bit(XMIT_SENDING, &(info->tx_state))) {
set_bit(XMIT_WAKEUP, &(info->tx_state));
return;
}
do {
unsigned int iobase = info->p_dev->resource[0]->start;
register struct sk_buff *skb;
int len;
clear_bit(XMIT_WAKEUP, &(info->tx_state));
if (!pcmcia_dev_present(info->p_dev))
return;
skb = skb_dequeue(&(info->txq));
if (!skb)
break;
/* Send frame */
len = btuart_write(iobase, 16, skb->data, skb->len);
set_bit(XMIT_WAKEUP, &(info->tx_state));
if (len == skb->len) {
kfree_skb(skb);
} else {
skb_pull(skb, len);
skb_queue_head(&(info->txq), skb);
}
info->hdev->stat.byte_tx += len;
} while (test_bit(XMIT_WAKEUP, &(info->tx_state)));
clear_bit(XMIT_SENDING, &(info->tx_state));
}
static void btuart_receive(struct btuart_info *info)
{
unsigned int iobase;
int boguscount = 0;
if (!info) {
BT_ERR("Unknown device");
return;
}
iobase = info->p_dev->resource[0]->start;
do {
info->hdev->stat.byte_rx++;
/* Allocate packet */
if (!info->rx_skb) {
info->rx_state = RECV_WAIT_PACKET_TYPE;
info->rx_count = 0;
info->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC);
if (!info->rx_skb) {
BT_ERR("Can't allocate mem for new packet");
return;
}
}
if (info->rx_state == RECV_WAIT_PACKET_TYPE) {
hci_skb_pkt_type(info->rx_skb) = inb(iobase + UART_RX);
switch (hci_skb_pkt_type(info->rx_skb)) {
case HCI_EVENT_PKT:
info->rx_state = RECV_WAIT_EVENT_HEADER;
info->rx_count = HCI_EVENT_HDR_SIZE;
break;
case HCI_ACLDATA_PKT:
info->rx_state = RECV_WAIT_ACL_HEADER;
info->rx_count = HCI_ACL_HDR_SIZE;
break;
case HCI_SCODATA_PKT:
info->rx_state = RECV_WAIT_SCO_HEADER;
info->rx_count = HCI_SCO_HDR_SIZE;
break;
default:
/* Unknown packet */
BT_ERR("Unknown HCI packet with type 0x%02x received",
hci_skb_pkt_type(info->rx_skb));
info->hdev->stat.err_rx++;
kfree_skb(info->rx_skb);
info->rx_skb = NULL;
break;
}
} else {
skb_put_u8(info->rx_skb, inb(iobase + UART_RX));
info->rx_count--;
if (info->rx_count == 0) {
int dlen;
struct hci_event_hdr *eh;
struct hci_acl_hdr *ah;
struct hci_sco_hdr *sh;
switch (info->rx_state) {
case RECV_WAIT_EVENT_HEADER:
eh = hci_event_hdr(info->rx_skb);
info->rx_state = RECV_WAIT_DATA;
info->rx_count = eh->plen;
break;
case RECV_WAIT_ACL_HEADER:
ah = hci_acl_hdr(info->rx_skb);
dlen = __le16_to_cpu(ah->dlen);
info->rx_state = RECV_WAIT_DATA;
info->rx_count = dlen;
break;
case RECV_WAIT_SCO_HEADER:
sh = hci_sco_hdr(info->rx_skb);
info->rx_state = RECV_WAIT_DATA;
info->rx_count = sh->dlen;
break;
case RECV_WAIT_DATA:
hci_recv_frame(info->hdev, info->rx_skb);
info->rx_skb = NULL;
break;
}
}
}
/* Make sure we don't stay here too long */
if (boguscount++ > 16)
break;
} while (inb(iobase + UART_LSR) & UART_LSR_DR);
}
static irqreturn_t btuart_interrupt(int irq, void *dev_inst)
{
struct btuart_info *info = dev_inst;
unsigned int iobase;
int boguscount = 0;
int iir, lsr;
irqreturn_t r = IRQ_NONE;
if (!info || !info->hdev)
/* our irq handler is shared */
return IRQ_NONE;
iobase = info->p_dev->resource[0]->start;
spin_lock(&(info->lock));
iir = inb(iobase + UART_IIR) & UART_IIR_ID;
while (iir) {
r = IRQ_HANDLED;
/* Clear interrupt */
lsr = inb(iobase + UART_LSR);
switch (iir) {
case UART_IIR_RLSI:
BT_ERR("RLSI");
break;
case UART_IIR_RDI:
/* Receive interrupt */
btuart_receive(info);
break;
case UART_IIR_THRI:
if (lsr & UART_LSR_THRE) {
/* Transmitter ready for data */
btuart_write_wakeup(info);
}
break;
default:
BT_ERR("Unhandled IIR=%#x", iir);
break;
}
/* Make sure we don't stay here too long */
if (boguscount++ > 100)
break;
iir = inb(iobase + UART_IIR) & UART_IIR_ID;
}
spin_unlock(&(info->lock));
return r;
}
static void btuart_change_speed(struct btuart_info *info,
unsigned int speed)
{
unsigned long flags;
unsigned int iobase;
int fcr; /* FIFO control reg */
int lcr; /* Line control reg */
int divisor;
if (!info) {
BT_ERR("Unknown device");
return;
}
iobase = info->p_dev->resource[0]->start;
spin_lock_irqsave(&(info->lock), flags);
/* Turn off interrupts */
outb(0, iobase + UART_IER);
divisor = SPEED_MAX / speed;
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT;
/*
* Use trigger level 1 to avoid 3 ms. timeout delay at 9600 bps, and
* almost 1,7 ms at 19200 bps. At speeds above that we can just forget
* about this timeout since it will always be fast enough.
*/
if (speed < 38400)
fcr |= UART_FCR_TRIGGER_1;
else
fcr |= UART_FCR_TRIGGER_14;
/* Bluetooth cards use 8N1 */
lcr = UART_LCR_WLEN8;
outb(UART_LCR_DLAB | lcr, iobase + UART_LCR); /* Set DLAB */
outb(divisor & 0xff, iobase + UART_DLL); /* Set speed */
outb(divisor >> 8, iobase + UART_DLM);
outb(lcr, iobase + UART_LCR); /* Set 8N1 */
outb(fcr, iobase + UART_FCR); /* Enable FIFO's */
/* Turn on interrupts */
outb(UART_IER_RLSI | UART_IER_RDI | UART_IER_THRI, iobase + UART_IER);
spin_unlock_irqrestore(&(info->lock), flags);
}
/* ======================== HCI interface ======================== */
static int btuart_hci_flush(struct hci_dev *hdev)
{
struct btuart_info *info = hci_get_drvdata(hdev);
/* Drop TX queue */
skb_queue_purge(&(info->txq));
return 0;
}
static int btuart_hci_open(struct hci_dev *hdev)
{
return 0;
}
static int btuart_hci_close(struct hci_dev *hdev)
{
btuart_hci_flush(hdev);
return 0;
}
static int btuart_hci_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
{
struct btuart_info *info = hci_get_drvdata(hdev);
switch (hci_skb_pkt_type(skb)) {
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;
}
/* Prepend skb with frame type */
memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
skb_queue_tail(&(info->txq), skb);
btuart_write_wakeup(info);
return 0;
}
/* ======================== Card services HCI interaction ======================== */
static int btuart_open(struct btuart_info *info)
{
unsigned long flags;
unsigned int iobase = info->p_dev->resource[0]->start;
struct hci_dev *hdev;
spin_lock_init(&(info->lock));
skb_queue_head_init(&(info->txq));
info->rx_state = RECV_WAIT_PACKET_TYPE;
info->rx_count = 0;
info->rx_skb = NULL;
/* Initialize HCI device */
hdev = hci_alloc_dev();
if (!hdev) {
BT_ERR("Can't allocate HCI device");
return -ENOMEM;
}
info->hdev = hdev;
hdev->bus = HCI_PCCARD;
hci_set_drvdata(hdev, info);
SET_HCIDEV_DEV(hdev, &info->p_dev->dev);
hdev->open = btuart_hci_open;
hdev->close = btuart_hci_close;
hdev->flush = btuart_hci_flush;
hdev->send = btuart_hci_send_frame;
spin_lock_irqsave(&(info->lock), flags);
/* Reset UART */
outb(0, iobase + UART_MCR);
/* Turn off interrupts */
outb(0, iobase + UART_IER);
/* Initialize UART */
outb(UART_LCR_WLEN8, iobase + UART_LCR); /* Reset DLAB */
outb((UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2), iobase + UART_MCR);
/* Turn on interrupts */
// outb(UART_IER_RLSI | UART_IER_RDI | UART_IER_THRI, iobase + UART_IER);
spin_unlock_irqrestore(&(info->lock), flags);
btuart_change_speed(info, DEFAULT_BAUD_RATE);
/* Timeout before it is safe to send the first HCI packet */
msleep(1000);
/* Register HCI device */
if (hci_register_dev(hdev) < 0) {
BT_ERR("Can't register HCI device");
info->hdev = NULL;
hci_free_dev(hdev);
return -ENODEV;
}
return 0;
}
static int btuart_close(struct btuart_info *info)
{
unsigned long flags;
unsigned int iobase = info->p_dev->resource[0]->start;
struct hci_dev *hdev = info->hdev;
if (!hdev)
return -ENODEV;
btuart_hci_close(hdev);
spin_lock_irqsave(&(info->lock), flags);
/* Reset UART */
outb(0, iobase + UART_MCR);
/* Turn off interrupts */
outb(0, iobase + UART_IER);
spin_unlock_irqrestore(&(info->lock), flags);
hci_unregister_dev(hdev);
hci_free_dev(hdev);
return 0;
}
static int btuart_probe(struct pcmcia_device *link)
{
struct btuart_info *info;
/* Create new info device */
info = devm_kzalloc(&link->dev, sizeof(*info), GFP_KERNEL);
if (!info)
return -ENOMEM;
info->p_dev = link;
link->priv = info;
link->config_flags |= CONF_ENABLE_IRQ | CONF_AUTO_SET_VPP |
CONF_AUTO_SET_IO;
return btuart_config(link);
}
static void btuart_detach(struct pcmcia_device *link)
{
btuart_release(link);
}
static int btuart_check_config(struct pcmcia_device *p_dev, void *priv_data)
{
int *try = priv_data;
if (!try)
p_dev->io_lines = 16;
if ((p_dev->resource[0]->end != 8) || (p_dev->resource[0]->start == 0))
return -EINVAL;
p_dev->resource[0]->end = 8;
p_dev->resource[0]->flags &= ~IO_DATA_PATH_WIDTH;
p_dev->resource[0]->flags |= IO_DATA_PATH_WIDTH_8;
return pcmcia_request_io(p_dev);
}
static int btuart_check_config_notpicky(struct pcmcia_device *p_dev,
void *priv_data)
{
static unsigned int base[5] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, 0x0 };
int j;
if (p_dev->io_lines > 3)
return -ENODEV;
p_dev->resource[0]->flags &= ~IO_DATA_PATH_WIDTH;
p_dev->resource[0]->flags |= IO_DATA_PATH_WIDTH_8;
p_dev->resource[0]->end = 8;
for (j = 0; j < 5; j++) {
p_dev->resource[0]->start = base[j];
p_dev->io_lines = base[j] ? 16 : 3;
if (!pcmcia_request_io(p_dev))
return 0;
}
return -ENODEV;
}
static int btuart_config(struct pcmcia_device *link)
{
struct btuart_info *info = link->priv;
int i;
int try;
/* First pass: look for a config entry that looks normal.
* Two tries: without IO aliases, then with aliases
*/
for (try = 0; try < 2; try++)
if (!pcmcia_loop_config(link, btuart_check_config, &try))
goto found_port;
/* Second pass: try to find an entry that isn't picky about
* its base address, then try to grab any standard serial port
* address, and finally try to get any free port.
*/
if (!pcmcia_loop_config(link, btuart_check_config_notpicky, NULL))
goto found_port;
BT_ERR("No usable port range found");
goto failed;
found_port:
i = pcmcia_request_irq(link, btuart_interrupt);
if (i != 0)
goto failed;
i = pcmcia_enable_device(link);
if (i != 0)
goto failed;
if (btuart_open(info) != 0)
goto failed;
return 0;
failed:
btuart_release(link);
return -ENODEV;
}
static void btuart_release(struct pcmcia_device *link)
{
struct btuart_info *info = link->priv;
btuart_close(info);
pcmcia_disable_device(link);
}
static const struct pcmcia_device_id btuart_ids[] = {
/* don't use this driver. Use serial_cs + hci_uart instead */
PCMCIA_DEVICE_NULL
};
MODULE_DEVICE_TABLE(pcmcia, btuart_ids);
static struct pcmcia_driver btuart_driver = {
.owner = THIS_MODULE,
.name = "btuart_cs",
.probe = btuart_probe,
.remove = btuart_detach,
.id_table = btuart_ids,
};
module_pcmcia_driver(btuart_driver);